WO2018131670A1

WO2018131670A1 - Copolymer and resin composition

Info

Publication number: WO2018131670A1
Application number: PCT/JP2018/000558
Authority: WO
Inventors: 中西　秀高; 慎也井本
Original assignee: 株式会社日本触媒
Priority date: 2017-01-13
Filing date: 2018-01-12
Publication date: 2018-07-19
Also published as: JP2019123854A; CN110167981B; KR20190055838A; JP6732952B2; CN110167981A; KR102190057B1; JPWO2018131670A1

Abstract

A copolymer which has a polymer chain (A) that has a unit derived from a diene and/or an olefin and a polymer chain (B) that has a unit derived from a (meth)acrylic monomer and a unit having a ring structure in the main chain. This copolymer is characterized in that the content ratio of the unit derived from a (meth)acrylic acid ester in the polymer chain (B) is from 45% by mass to 98% by mass (inclusive).

Description

Copolymer and resin composition

The present invention provides a copolymer having a polymer chain having a unit derived from a diene and / or an olefin, a unit derived from a (meth) acrylic monomer, and a polymer chain having a unit having a ring structure in the main chain, It is related with the resin composition containing a copolymer, the optical film formed from these, a polarizing plate, an image display apparatus, and the manufacturing method of the said copolymer.

Transparent resins are widely used in optical materials such as optical lenses, prisms, mirrors, optical disks, optical fibers, liquid crystal display sheets, films, and light guide plates. Conventionally, (meth) acrylic resins have been widely used as such transparent resins, but (meth) acrylic resins sometimes have difficulty in achieving both heat resistance and mechanical strength. For example, (meth) acrylic resins can improve heat resistance while maintaining transparency by introducing a ring structure into the main chain (Patent Document 1, etc.), but introducing a ring structure into the main chain As a result, the resin itself becomes hard and brittle and easily breaks, and mechanical strength such as folding strength is reduced during film processing. Therefore, as a method for increasing the strength with a (meth) acrylic resin, Patent Document 2 discloses a method of imparting strength by biaxial stretching, and Patent Document 3 discloses a flexibility having a low glass transition temperature. A method of blending a resin is disclosed. However, when strength is imparted by biaxial stretching, there is a problem that strength anisotropy occurs due to the stretching ratio or the like. Moreover, when mix | blending a flexible resin, coexistence with transparency was difficult and there was room for improvement. Patent Document 4 discloses a copolymer obtained by grafting a (meth) acrylic polymer to a polyolefin, but such a graft copolymer has a low glass transition temperature and insufficient heat resistance. There was room for improvement. Furthermore, when a transparent resin is applied to an optical material, if a gelled product is contained in the resin, it will cause foreign matter and appearance defects and lead to a decrease in production efficiency. It is desirable not to.

JP 2006-171464 A JP 2005-162835 A JP 2007-100044 A JP-A-5-295183

The present invention has been made in view of the above circumstances, and its purpose is to provide a copolymer having excellent transparency, mechanical strength, and heat resistance, providing them in a well-balanced manner and generating less gelled product, and It is in providing the resin composition containing and the method of manufacturing such a copolymer.

The present invention includes the following inventions.
[1] having a polymer chain (A) having a unit derived from a diene and / or an olefin, a unit derived from a (meth) acrylic monomer, and a polymer chain (B) having a unit having a ring structure in the main chain A copolymer comprising:
In the polymer chain (B), a content ratio of the unit derived from the (meth) acrylic acid ester is 45% by mass or more and 98% by mass or less.
[2] The copolymer according to [1], wherein the polymer chain (B) is grafted to the polymer chain (A).
[3] The copolymer according to [1] or [2], wherein the ring structure is a lactone ring structure and / or a maleimide structure.
[4] The total content of the unit derived from the (meth) acrylic monomer and the unit having a ring structure in the main chain in the polymer chain (B) is 90% by mass or more [1] to [3 ] The copolymer in any one of.
[5] A resin composition comprising the copolymer according to any one of [1] to [4] and a (meth) acrylic polymer.
[6] The resin composition according to [5], wherein the (meth) acrylic polymer has units derived from the (meth) acrylic monomer.
[7] The resin composition according to [5] or [6], wherein the (meth) acrylic polymer has a unit having a ring structure in the main chain.
[8] The resin composition according to any one of [5] to [7], which has a glass transition temperature at 100 ° C. or higher and lower than 100 ° C., respectively.
[9] The resin composition according to any one of [5] to [8], wherein an insoluble content in chloroform is 10% by mass or less.
[10] An optical film comprising the copolymer according to any one of [1] to [4] or the resin composition according to any one of [5] to [9].
[11] A polarizing plate comprising the optical film according to [10].
[12] An image display device comprising the optical film according to [10].
[13] A method for producing a copolymer according to any one of [1] to [4],
In the presence of the polymer (P1) having units derived from diene and / or olefin, a monomer component containing a (meth) acrylic monomer and a monomer having a polymerizable double bond in the ring structure is polymerized. A process for producing a copolymer, comprising the step of:
[14] A method for producing a copolymer according to any one of [1] to [4],
Polymerizing a monomer component containing a (meth) acrylic monomer in the presence of the polymer (P1) having a unit derived from a diene and / or an olefin;
And a step of forming a ring structure in the main chain of the polymer chain having a unit derived from the (meth) acrylic monomer formed in the polymerization step.
[15] The method for producing a copolymer according to [13], further comprising a step of filtering the resin solution obtained in the polymerization step.
[16] The method for producing a copolymer according to [14], further comprising a step of filtering the resin solution obtained in the ring structure forming step.

The copolymer of the present invention and the resin composition containing the copolymer are excellent in transparency, mechanical strength, and heat resistance, are provided with a good balance, and generate less gelled product. In addition, according to the production method of the present invention, it is possible to obtain a copolymer with little generation of gelled products, excellent transparency, mechanical strength, and heat resistance and having these in a well-balanced manner.

[1. Copolymer)
The copolymer of the present invention has a diene or olefin polymer chain (A) and a (meth) acrylic polymer chain (B) having a ring structure. The copolymer of the present invention is excellent in transparency, mechanical strength (for example, impact strength, etc.), and heat resistance, and is provided with a good balance between them, and is less likely to generate gelated products during production. Hereinafter, the copolymer of the present invention is referred to as “copolymer (P)”.

The copolymer (P) has a structure in which a diene or olefin polymer chain (A) and a (meth) acrylic polymer chain (B) having a ring structure are copolymerized. Although the form of copolymerization is not limited, it is preferably a graft copolymer obtained by grafting a (meth) acrylic polymer chain (B) having a ring structure to a diene or olefin polymer chain (A). Hereinafter, the diene or olefin polymer chain (A) may be simply referred to as “polymer chain (A)”, and the (meth) acrylic polymer chain (B) having a ring structure may be simply referred to as “polymer chain (B)”. .

The (meth) acrylic polymer chain (B) having a ring structure usually gives a hard and brittle resin, but this is copolymerized with a diene or olefinic polymer chain (A) so that the composition of the polymer chain (B) is appropriate. By controlling to, a copolymer (P) having both heat resistance and mechanical strength can be obtained. In addition, it is possible to reduce the generation of gelled products during production. The copolymer (P) thus obtained has high transparency despite having a diene or olefin component. Further, even when the copolymer (P) is blended with a (meth) acrylic polymer, these properties are not impaired, and since the dispersibility is excellent, transparency is not impaired.

When forming a film from the copolymer (P), a film having high strength and high heat resistance can be obtained without performing an orientation treatment such as a stretching treatment. Therefore, a film having desired optical characteristics can be easily obtained. For example, since it has high strength, high heat resistance, and high transparency, an isotropic film or a low retardation film can be formed efficiently. On the other hand, due to the ring structure, anisotropy can be easily expressed, and therefore a retardation film can be formed by an orientation treatment such as a stretching treatment. Moreover, when it is set as an optical film, it can be set as a thing with few foreign materials and external appearance defect.

The polymer chain (A) contained in the copolymer (P) will be described. The polymer chain (A) has at least units derived from diene and / or olefin. The unit derived from diene and / or olefin functions as a soft component in the copolymer (P). By including the unit derived from diene and / or olefin, the mechanical strength (for example, impact strength) of the copolymer is enhanced and the brittleness is reduced while ensuring the transparency of the copolymer (P). be able to.

The dienes include 1,3-butadiene (also known as butadiene), 2-methyl-1,3-butadiene (also known as isoprene), 1,3-pentadiene, 1,4-pentadiene, 1,5-hexadiene, 2, Alkadienes such as 5-dimethyl-1,5-hexadiene (also known as diisobutene) are preferably used, and conjugated dienes such as 1,3-butadiene, 2-methyl-1,3-butadiene, and 1,3-pentadiene are particularly preferable. More preferred. As the olefin, monoolefins such as ethylene, propylene, 1-butene, isobutene, 2-methyl-1-butene, 3-methyl-1-butene, 1-tetradecene, 1-octadecene and the like are preferably used. More preferred are α-olefins which are alkenes with a carbon double bond in the α-position. These dienes and olefins preferably have 2 or more carbon atoms, more preferably 3 or more, more preferably 20 or less, even more preferably 10 or less, and even more preferably 6 or less. Units derived from dienes and / or olefins are defined as units formed by polymerizing these dienes and / or olefins. Olefin-derived units are not limited to those actually formed by (co) polymerization of olefins, but may be formed by hydrogenating diene-derived units.

The polymer chain (A) is, for example, an olefin (co) polymer such as polyethylene, polypropylene, polybutene-1, ethylene-propylene copolymer, ethylene-butene copolymer; polyisoprene, polybutadiene, isoprene-butadiene copolymer Diene (co) polymers such as: ethylene-propylene-diene copolymer, isobutene-isoprene copolymer and other olefin and diene copolymers are included in the structure of the main chain. The olefin (co) polymer is preferably an α-olefin (co) polymer, the diene (co) polymer is preferably a conjugated diene (co) polymer, and the olefin-diene copolymer is an α-olefin. Copolymers of conjugated dienes are preferred. Among these, α-olefin and conjugated diene copolymers such as polyisoprene and isobutene-isoprene copolymers, polyethylene, and polypropylene are more preferable.

The polymer chain (A) may further have units derived from other unsaturated monomers in addition to the units derived from diene and / or olefin. The other unsaturated monomer is not particularly limited as long as it is a compound having a polymerizable double bond. For example, vinyl esters such as vinyl acetate and vinyl propionate; (meth) acrylic acid, maleic anhydride, (meta ) Unsaturated carboxylic acids such as methyl acrylate and ethyl (meth) acrylate and esters thereof; aromatic vinyl compounds such as styrene, vinyl toluene, methoxy styrene, α-methyl styrene, 2-vinyl pyridine; vinyl trimethoxy silane; and vinyl silanes such as γ- (meth) acryloyloxypropylmethoxysilane. The polymer chain (A) may be a copolymer of these other unsaturated monomers and diene and / or olefin. The content ratio of the units derived from diene and / or olefin in the polymer chain (A) is, for example, preferably 30% by mass or more, more preferably 40% by mass or more, further preferably 50% by mass or more, and 55% by mass. % Or more is still more preferable, 90 mass% or less is preferable, 86 mass% or less is more preferable, and 83 mass% or less is further more preferable.

When the polymer chain (A) has units derived from other unsaturated monomers, the polymer chain (A) may be a random copolymer of a diene and / or olefin and another unsaturated monomer. It may be a block copolymer or a graft copolymer. Among these, a block copolymer is preferable because the function as a soft component of the unit derived from diene and / or olefin is suitably expressed. In this case, the polymer chain (A) has a polymer block (a1) having units derived from diene and / or olefin and a polymer block (a2) having units derived from other unsaturated monomers. Become.

When the polymer chain (A) has a polymer block (a2) having units derived from other unsaturated monomers, the transparency of the copolymer (P) is improved while ensuring the mechanical strength. It is preferable that the polymer block (a2) is composed of units derived from an aromatic vinyl monomer. In this case, in the polymer chain (A), the polymer block (a1) functions as a soft component, and the polymer block (a2) functions as a hard component.

The aromatic vinyl monomer that gives the polymer block (a2) is not particularly limited as long as it is a compound in which a vinyl group is bonded to an aromatic ring. For example, styrene, vinyl toluene, methoxystyrene, α-methylstyrene, α- Styrene monomers such as hydroxymethylstyrene and α-hydroxyethylstyrene; polycyclic aromatic hydrocarbon ring vinyl monomers such as 2-vinylnaphthalene; N-vinylcarbazole, 2-vinylpyridine, vinylimidazole, vinylthiophene And aromatic heterocyclic vinyl monomers. Among these, a styrene monomer is preferable. Styrene monomers include not only styrene, but also styrene derivatives in which an arbitrary substituent is bonded to the polymerizable double bond carbon or benzene ring of styrene. Examples of the substituent include an alkyl group, an alkoxy group, Examples include a hydroxyl group, a halogen group, an amino group, a nitro group, and a sulfo group. The alkyl group and alkoxy group bonded to styrene preferably have 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms. The alkyl group and alkoxy group bonded to styrene have at least a part of hydrogen atoms as hydroxyl groups or halogen atoms. It may be substituted with a group.

Examples of the polymer chain (A) having a polymer block (a1) having a unit derived from a diene and / or an olefin and a polymer block (a2) having a unit derived from an aromatic vinyl monomer include styrene- Butadiene block copolymer, styrene-butadiene-styrene block copolymer, hydrogenated product of styrene-butadiene-styrene block copolymer (for example, styrene-ethylene / butylene-styrene block copolymer, styrene-butadiene / butylene- Styrene block copolymer), styrene-isoprene block copolymer, styrene-isoprene-styrene block copolymer, hydrogenated product of styrene-isoprene-styrene block copolymer (for example, styrene-ethylene / propylene-styrene block copolymer) Polymer) etc.

When the polymer chain (A) has a polymer block (a1) having a unit derived from a diene and / or an olefin, and a polymer block (a2) having a unit derived from an aromatic vinyl monomer, the polymer chain ( In A), the polymer block (a2) is preferably bonded to both sides of the polymer block (a1). By constituting the polymer chain (A) in this way, the polymer chain (A) functions as an elastomer, and the mechanical strength of the copolymer can be further increased. In this case, the polymer chain (A) may be a triblock copolymer, a multiblock copolymer, or a radial block copolymer. A triblock copolymer is preferable from the viewpoint of easy property control and easy introduction of the polymer chain (B) into the copolymer (P).

When the polymer chain (A) has a polymer block (a1) having a unit derived from a diene and / or an olefin, and a polymer block (a2) having a unit derived from an aromatic vinyl monomer, the polymer block (A1) may further have units derived from other unsaturated monomers in addition to the units derived from dienes and / or olefins. Examples of other unsaturated monomers in this case include vinyl esters such as vinyl acetate and vinyl propionate; (meth) acrylic acid, maleic anhydride, methyl (meth) acrylate, ethyl (meth) acrylate, and the like. Unsaturated carboxylic acids and esters thereof; aromatic vinyl compounds such as styrene, vinyltoluene, methoxystyrene, α-methylstyrene, 2-vinylpyridine; vinyltrimethoxysilane, γ- (meth) acryloyloxypropylmethoxysilane, etc. Vinyl silane etc. are mentioned. The polymer block (a1) may be a copolymer of these other unsaturated monomers and diene and / or olefin. The polymer block (a1) preferably contains a diene and / or olefin-derived unit as a main component. In 100% by mass of the polymer block (a1), the content ratio of the diene and / or olefin-derived unit is 50. It is preferably at least mass%, more preferably at least 60 mass%, and even more preferably at least 70 mass%. The polymer block (a1) may be substantially composed only of units derived from diene and / or olefin. For example, the unit derived from diene and / or olefin may be 99% by mass or more.

When the polymer chain (A) has a polymer block (a1) having a unit derived from a diene and / or an olefin, and a polymer block (a2) having a unit derived from an aromatic vinyl monomer, the polymer block (A2) may further have a unit derived from another unsaturated monomer in addition to the unit derived from the aromatic vinyl monomer. Examples of other unsaturated monomers in this case include vinyl esters such as vinyl acetate and vinyl propionate; (meth) acrylic acid, maleic anhydride, methyl (meth) acrylate, ethyl (meth) acrylate, and the like. Unsaturated carboxylic acids and esters thereof; aromatic vinyl compounds such as styrene, vinyltoluene, methoxystyrene, α-methylstyrene, 2-vinylpyridine; vinyltrimethoxysilane, γ- (meth) acryloyloxypropylmethoxysilane, etc. Vinyl silane etc. are mentioned. The polymer block (a2) may be a copolymer of these other unsaturated monomers and aromatic vinyl monomers. In addition, it is preferable that a polymer block (a2) contains the unit derived from an aromatic vinyl monomer as a main component, and the content rate of the unit derived from an aromatic vinyl monomer in 100 mass% of polymer blocks (a2). Is preferably 70% by mass or more, more preferably 80% by mass or more, and still more preferably 90% by mass or more. The polymer block (a2) may be substantially composed only of units derived from an aromatic vinyl monomer. For example, the unit derived from an aromatic vinyl monomer may be 99% by mass or more.

In the polymer chain (A), the content of the polymer block (a2) is preferably 10% by mass or more, more preferably 14% by mass or more, further preferably 17% by mass or more, and preferably 55% by mass or less. 50 mass% or less is more preferable, and 45 mass% or less is further more preferable. As a result, the polymer chain (A) has a soft component and a hard component in a well-balanced manner, and it becomes easy to increase transparency while ensuring the mechanical strength of the copolymer (P). From the same viewpoint, the content of the polymer block (a1) in the polymer chain (A) is preferably 45% by mass or more, more preferably 50% by mass or more, further preferably 55% by mass or more, and 90% % By mass or less is preferable, 86% by mass or less is more preferable, and 83% by mass or less is more preferable.

The weight average molecular weight of the polymer chain (A) is preferably 10000 or more, more preferably 50,000 or more, further preferably 10,000 or more, still more preferably 30,000 or more, and preferably 500,000 or less, 300,000 or less is more preferable, 200,000 or less is more preferable, and 100,000 or less is even more preferable. By making the weight average molecular weight of a polymer chain (A) into such a range, it becomes easy to ensure the intensity | strength and transparency of a copolymer (P).

The polymer chain (B) contained in the copolymer (P) will be described. The polymer chain (B) has at least a unit derived from a (meth) acrylic monomer and has a ring structure. The polymer chain (B) is preferably grafted to the polymer chain (A). Therefore, the copolymer (P) is a graft copolymer, and the polymer chain (B) is used as a graft chain of the graft copolymer. It is preferable to have. The transparency of the copolymer (P) can be enhanced by the polymer chain (B).

The unit derived from the (meth) acrylic monomer of the polymer chain (B) (hereinafter sometimes referred to as “(meth) acrylic unit”) is obtained by polymerizing the (meth) acrylic monomer. (B) can be introduced. The (meth) acrylic monomer includes (meth) acrylic acid and derivatives thereof, and the (meth) acrylic monomer has an alkyl group (preferably having 1 to 4 carbon atoms) at the α-position or β-position. Alkyl group) may be bonded, and in the alkyl group, at least a part of the hydrogen atoms may be substituted with a hydroxyl group or a halogen group. The form of the carboxylic acid contained in the unit derived from the (meth) acrylic monomer is not particularly limited, and examples thereof include free acid, ester, salt, acid amide and the like.

The polymer chain (B) has at least a unit derived from a (meth) acrylic acid ester as a (meth) acrylic unit. (Meth) acrylic acid ester units that give units derived from (meth) acrylic acid esters include linear, branched or cyclic aliphatic hydrocarbon groups and aromatic carbon atoms on the oxygen atom of the ester bond of (meth) acrylic acid. (Meth) acrylic acid ester to which a hydrogen group is bonded is exemplified.

Examples of the (meth) acrylic acid ester having a linear or branched aliphatic hydrocarbon group include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, and (meth) acrylic. Isopropyl acid, n-butyl (meth) acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, pentyl (meth) acrylate, amyl (meth) acrylate , Isoamyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, decyl (meth) acrylate, (meth ) Dodecyl acrylate, pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, (meth) a Acrylic acid heptadecyl, (meth) of octadecyl acrylate (meth) acrylic acid alkyl. The alkyl group of the alkyl (meth) acrylate is preferably a C1-18 alkyl group, and more preferably a C1-12 alkyl group. In this specification, “C1-18” and “C1-12” mean “1 to 18 carbon atoms” and “1 to 12 carbon atoms”, respectively.

Examples of the (meth) acrylic acid ester having a cyclic aliphatic hydrocarbon group include cyclopropyl (meth) acrylate, cyclobutyl (meth) acrylate, cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, ) Acrylic acid cycloalkyl; Cross-linked cyclic (meth) acrylates such as isobornyl (meth) acrylate. The cycloalkyl group of the cycloalkyl (meth) acrylate is preferably a C3-20 cycloalkyl group, and more preferably a C3-12 cycloalkyl group.

Examples of (meth) acrylic acid ester having an aromatic hydrocarbon group include phenyl (meth) acrylate, tolyl (meth) acrylate, xylyl (meth) acrylate, naphthyl (meth) acrylate, and binaphthyl (meth) acrylate. (Meth) acrylates such as anthryl (meth) acrylate; aryl (meth) acrylates such as benzyl (meth) acrylate; aryloxyalkyl (meth) acrylates such as phenoxyethyl (meth) acrylate; Can be mentioned. The aryl group of aryl (meth) acrylate is preferably a C6-20 aryl group, more preferably a C6-14 aryl group. The aralkyl group of (meth) acrylic acid aralkyl is preferably a C6-10 aryl C1-4 alkyl group. The aryloxyalkyl group of aryloxyalkyl (meth) acrylate is preferably a C6-10 aryloxy C1-4 alkyl group, more preferably a phenoxy C1-4 alkyl group.

(Meth) acrylic acid ester may have a substituent such as a hydroxyl group, a halogen group, an alkoxy group or an epoxy group. Examples of such (meth) acrylic acid esters include hydroxyalkyl (meth) acrylates such as 2-hydroxyethyl (meth) acrylate; chloromethyl (meth) acrylate, 2-chloroethyl (meth) acrylate and the like ( (Meth) acrylic acid alkyl halides; (meth) alkoxyalkyl (meth) acrylates such as 2-methoxyethyl acrylate; and (meth) acrylic acid epoxyalkyls such as glycidyl (meth) acrylate. The alkyl group of hydroxyalkyl (meth) acrylate and epoxyalkyl (meth) acrylate is preferably a C1-12 alkyl group. The alkoxyalkyl group of the alkoxyalkyl (meth) acrylate is preferably a C1-12 alkoxy C1-12 alkyl group.

The polymer chain (B) has a unit having a ring structure in the main chain (hereinafter sometimes referred to as “ring structure unit”) in addition to the (meth) acryl unit. When the polymer chain (B) has a ring structure in the main chain, the heat resistance of the copolymer (P) can be increased. In addition, improvements in solvent resistance, surface hardness, adhesion, oxygen and water vapor barrier properties, and various optical properties can be expected. Furthermore, when the copolymer (P) or a resin composition containing the copolymer is used as a film or sheet, the dimensional stability and shape stability under high temperature and high humidity conditions can be enhanced. By stretching the film formed in this manner, a large retardation can be expressed due to the ring structure of the polymer chain (B), and application as a retardation film becomes possible. This feature enables application of the copolymer (P) and a resin composition containing the copolymer to an optical film such as a retardation film or a polarizer protective film having a function of a retardation film.

The ring structure of the main chain of the polymer chain (B) may contain a part or all of the (meth) acrylic monomer in the ring structure, and is introduced separately from the (meth) acrylic monomer. It may be a ring structure. When part or all of the (meth) acrylic monomer is included in the ring structure, for example, the two carboxylic acid groups of the units derived from the adjacent (meth) acrylic monomer are converted to acid anhydrides. Or by imidization. In addition, when one of the units derived from the adjacent (meth) acrylic monomer has a protonic hydrogen atom-containing group such as a hydroxyl group or an amino group, it is derived from this one (meth) acrylic monomer. A ring structure can also be formed by condensing the protonic hydrogen atom-containing group of the unit and the carboxylic acid group of the unit derived from the other (meth) acrylic monomer. When the ring structure is introduced separately from the unit derived from the (meth) acrylic monomer, for example, a (meth) acrylic monomer and a monomer having a polymerizable double bond in the ring structure are included. What is necessary is just to copolymerize.

The ring structure may be any of a 4-membered ring structure, a 5-membered ring structure, a 6-membered ring structure, a 7-membered ring structure, an 8-membered ring structure, and the like, and preferably a 5-membered ring structure or a 6-membered ring structure.

As the ring structure, from the viewpoint of the heat resistance of the copolymer (P), a lactone ring structure, a cyclic imide structure (for example, a maleimide structure, a glutarimide structure, etc.), a cyclic anhydride structure (for example, a maleic anhydride structure, an anhydrous structure) Glutaric acid structure etc.) are preferred. One type of these ring structures may be contained in the main chain of the polymer chain (B), or two or more types may be contained. Among these, at least one selected from a lactone ring structure, a maleimide structure, a maleic anhydride structure, a glutarimide structure, and a glutaric anhydride structure is preferable.

When the polymer chain (B) has a lactone ring structure as the ring structure of the main chain, the number of ring members of the lactone ring structure is not particularly limited, and may be any one of 4 to 8 membered rings, for example. The lactone ring structure is preferably a 5-membered ring or a 6-membered ring, and more preferably a 6-membered ring, from the viewpoint of excellent stability of the ring structure.

Examples of the lactone ring structure include the structure disclosed in Japanese Patent Application Laid-Open No. 2004-168882. The lactone ring structure is easy to introduce, and more specifically, the precursor (the lactone ring structure prior to lactone cyclization). From the reasons that the polymerization yield of the polymer) is high, the lactone ring content in the cyclization condensation reaction of the precursor can be increased, and the polymer having a unit derived from (meth) acrylate can be used as the precursor. A structure represented by the formula (1) is preferably shown. In the following formula (1), R ¹ , R ² and R ³ each independently represent a hydrogen atom or a substituent.

Examples of the substituent of R ¹ , R ² and R ^{3 in} the formula (1) include organic residues such as a hydrocarbon group, such as a C1-20 hydrocarbon group which may contain an oxygen atom. Can be mentioned. Examples of the hydrocarbon group include saturated or unsaturated linear, branched or cyclic aliphatic hydrocarbon groups and aromatic hydrocarbon groups. Examples of the aliphatic hydrocarbon group include a C1-20 alkyl group such as a methyl group, an ethyl group, an n-propyl group, and an isopropyl group; a C2-20 alkenyl group such as an ethenyl group and a propenyl group; a cyclopentyl group, a cyclohexyl group, and the like. And a C3-20 cycloalkyl group. Examples of the aromatic hydrocarbon group include C6-20 aryl groups such as phenyl group, tolyl group, xylyl group, naphthyl group and biphenyl group; C7-20 aralkyl groups such as benzyl group and phenylethyl group. These hydrocarbon groups may contain an oxygen atom. Specifically, at least one hydrogen atom of the hydrocarbon group is selected from a hydroxyl group, a carboxyl group, an ether group and an ester group. It may be substituted with a group.

The lactone ring structure includes, for example, an ester group of a unit derived from an adjacent (meth) acrylic acid ester and a unit derived from a (meth) acrylic monomer having a protonic hydrogen atom-containing group such as a hydroxyl group or an amino group. Cyclocondensation with a protic hydrogen atom-containing group can be introduced into the polymer chain (B).

In the lactone ring structure of the formula (1), R ¹ and R ² are each independently a hydrogen atom or C1− from the viewpoint that it is easy to obtain a copolymer (P) having excellent heat resistance and low birefringence. an 20 alkyl group, R ³ is preferably a hydrogen atom or a methyl group, R ¹ and R ² are each independently a hydrogen atom or a methyl group, that R ³ is a hydrogen atom or a methyl group More preferred.

For example, the lactone ring structure is obtained by polymerizing (preferably copolymerizing) a (meth) acrylic monomer A having a hydroxy group and a (meth) acrylic monomer B to form a hydroxy group and an ester group in the molecular chain. Or after introducing a carboxyl group, it can form by making dealcoholization or dehydration cyclocondensation occur between these hydroxy groups and ester groups or carboxyl groups. The (meth) acrylic monomer A having a hydroxy group is essential as a polymerization component, and the (meth) acrylic monomer B includes the monomer A. Monomer B may or may not coincide with monomer A. When the monomer B coincides with the monomer A, the monomer A is homopolymerized.

Examples of the (meth) acrylic monomer A having a hydroxy group include 2- (hydroxymethyl) acrylic acid, 2- (hydroxyethyl) acrylic acid, and alkyl 2- (hydroxymethyl) acrylate (for example, 2- (hydroxy Methyl) methyl acrylate, 2- (hydroxymethyl) ethyl acrylate, 2- (hydroxymethyl) isopropyl acrylate, 2- (hydroxymethyl) acrylate n-butyl, 2- (hydroxymethyl) acrylate t-butyl) , Alkyl 2- (hydroxyethyl) acrylate (for example, methyl 2- (hydroxyethyl) acrylate, ethyl 2- (hydroxyethyl) acrylate) and the like, preferably a monomer having a hydroxyallyl moiety. Some 2- (hydroxymethyl) acrylic acid and 2- (hydroxymethyl) ), And alkyl acrylate. Particularly preferred are methyl 2- (hydroxymethyl) acrylate and ethyl 2- (hydroxymethyl) acrylate.

As the (meth) acrylic monomer B, a monomer having a vinyl group and an ester group or a carboxyl group is preferable. For example, (meth) acrylic acid, alkyl (meth) acrylate (for example, (meth) acrylic) Methyl methacrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, cyclohexyl (meth) acrylate), aryl (meth) acrylate (Eg, phenyl (meth) acrylate, benzyl (meth) acrylate), 2- (hydroxyalkyl) alkyl acrylate (eg, 2- (hydroxymethyl) methyl acrylate, 2- (hydroxymethyl) ethyl acrylate Such as alkyl 2- (hydroxymethyl) acrylate and 2- (hydroxyethyl) acrylate 2- (hydroxyethyl) alkyl acrylate) such as Le like.

The polymer chain (B) may have only one type of lactone ring structure represented by the formula (1), or may have two or more types.

When the polymer chain (B) has a maleic anhydride structure or a maleimide structure as the ring structure of the main chain, the maleic anhydride structure or the maleimide structure is preferably a structure represented by the following formula (2). In the following formula (2), R ⁴ and R ⁵ each independently represent a hydrogen atom or a methyl group, R ⁶ represents a hydrogen atom or a substituent, X ¹ represents an oxygen atom or a nitrogen atom, and X ¹ When n is an oxygen atom, n1 = 0, and when X ¹ is a nitrogen atom, n1 = 1.

Examples of the substituent of R ^{6 in} the formula (2) include a hydrocarbon group, and examples thereof include a C1-20 hydrocarbon group which may have a substituent such as halogen. Examples of the hydrocarbon group include saturated or unsaturated linear, branched or cyclic aliphatic hydrocarbon groups and aromatic hydrocarbon groups. Examples of the aliphatic hydrocarbon group include a C1-6 alkyl group such as a methyl group, an ethyl group, an n-propyl group, and an isopropyl group; a C2-6 alkenyl group such as an ethenyl group and a propenyl group; a cyclopentyl group, a cyclohexyl group, and the like. And a C3-20 cycloalkyl group. Examples of the aromatic hydrocarbon group include C6-20 aryl groups such as phenyl group, tolyl group, xylyl group, naphthyl group and biphenyl group; C7-20 aralkyl groups such as benzyl group and phenylethyl group. These hydrocarbon groups may have a substituent such as halogen.

When X ¹ is an oxygen atom, the ring structure represented by the formula (2) is a maleic anhydride structure. The maleic anhydride structure can be introduced into the polymer chain (B), for example, by copolymerizing maleic anhydride and a (meth) acrylic monomer (for example, (meth) acrylic acid ester). .

When X ¹ is a nitrogen atom, the ring structure represented by the formula (2) is a maleimide structure. The maleimide structure can be introduced into the polymer chain (B) by, for example, copolymerizing maleimide and a (meth) acrylic monomer (for example, (meth) acrylic acid ester). As the maleimide structure, for example, an N-substituted unsubstituted maleimide structure, N-methylmaleimide structure, N-ethylmaleimide structure, N-cyclohexylmaleimide structure, N-phenylmaleimide structure, N-naphthylmaleimide structure, N-benzylmaleimide Examples include the structure. Further, as the maleimide giving the maleimide structure, maleimide, N-methylmaleimide, N-ethylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide, N-naphthylmaleimide, N-benzylmaleimide, etc. are used. be able to.

When the polymer chain (B) has a maleimide structure in which X ¹ is a nitrogen atom, R ⁴ and R ⁵ are excellent in heat resistance and easy to obtain a copolymer (P) having a low birefringence. R ⁶ is preferably a C 3-20 cycloalkyl group or a C 6-20 aromatic group (aryl group, aralkyl group, etc.), R ⁴ and R ⁵ are hydrogen atoms, and R ⁶ is cyclohexyl. More preferably, it is a group or a phenyl group.

The polymer chain (B) may have only one type of ring structure represented by the formula (2), or may have two or more types.

When the polymer chain (B) has a glutarimide structure or a glutaric anhydride structure as the ring structure of the main chain, the structure represented by the following formula (3) is preferably shown as the glutarimide structure or the glutaric anhydride structure. In the following formula (3), R ⁷ and R ⁸ each independently represent a hydrogen atom or an alkyl group, R ⁹ represents a hydrogen atom or a substituent, X ² represents an oxygen atom or a nitrogen atom, and X ² There are n2 = 0 when the oxygen atom, a n2 = 1 when X ² is a nitrogen atom.

In the formula (3), the alkyl group of R ⁷ and R ⁸ is preferably a linear or branched alkyl group, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, and an n-butyl group. Group, isobutyl group, tert-butyl group, n-pentyl group, isopentyl group, n-hexyl group, isohexyl group, n-heptyl group, isoheptyl group, n-octyl group, 2-ethylhexyl group, etc. An alkyl group etc. are mentioned. R ⁷ and R ⁸ are each independently preferably a hydrogen atom or a C1-4 alkyl group from the viewpoint that it is easy to obtain a copolymer (P) having excellent heat resistance and a low birefringence index. An atom or a methyl group is more preferable.

Examples of the substituent for R ^{9 in} the formula (3) include a hydrocarbon group, and examples thereof include a C1-20 hydrocarbon group which may have a substituent such as halogen. Examples of the hydrocarbon group include saturated or unsaturated linear, branched or cyclic aliphatic hydrocarbon groups and aromatic hydrocarbon groups. Examples of the aliphatic hydrocarbon group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, an n-hexyl group, C1-10 alkyl groups such as isohexyl group, n-heptyl group, isoheptyl group, n-octyl group and 2-ethylhexyl; C2-10 alkenyl groups such as ethenyl group and propenyl group; cyclopropyl group, cyclobutyl group and cyclopentyl Group, a C3-12 cycloalkyl group such as a cyclohexyl group, and the like. Examples of the aromatic hydrocarbon group include C6-20 aryl groups such as phenyl group, tolyl group, xylyl group, naphthyl group, biphenyl group, binaphthyl group and anthryl group; C7-20 aralkyl groups such as benzyl group and phenylethyl group Groups and the like. These hydrocarbon groups may have a substituent such as halogen. Among these, R ⁹ is a C1-4 alkyl group, a C3-7 cycloalkyl group, a C6-20 aryl, because it is easy to obtain a copolymer (P) having excellent heat resistance and a small birefringence. Or a C7-20 aralkyl group, more preferably a methyl group, a cyclohexyl group, a phenyl group, or a tolyl group.

When X ² is an oxygen atom, the ring structure represented by the formula (3) is a glutaric anhydride structure. The glutaric anhydride structure can be introduced into the polymer chain (B) by acidifying two carboxylic acid groups of units derived from adjacent (meth) acrylic monomers, for example.

When X ² is a nitrogen atom, the ring structure represented by the formula (3) is a glutarimide structure. The glutarimide structure is, for example, imidization of two carboxylic acid groups of a unit derived from an adjacent (meth) acrylic monomer, or an amide group of a unit derived from an adjacent (meth) acrylic acid amide and (meth) It can introduce | transduce into a polymer chain (B) by carrying out cyclization condensation with the ester group of the unit derived from an acrylate ester.

In the ring structure of formula (3), R ⁷ and R ⁸ are each independently a hydrogen atom or a methyl group from the viewpoint that it is easy to obtain a copolymer (P) having excellent heat resistance and low birefringence. R ⁹ is preferably a C 1-10 alkyl group, a C 3-12 cycloalkyl group, or a C 6-20 aromatic group, and R ⁷ and R ⁸ are each independently a hydrogen atom or a methyl group, ⁹ is more preferably a C1-4 alkyl group, a C3-7 cycloalkyl group, a C6-20 aryl group, or a C7-20 aralkyl group, and R ⁷ and R ⁸ are each independently a hydrogen atom or a methyl group. There, R ⁹ is a methyl group, a cyclohexyl group, a phenyl group, or more preferably tolyl group, R ⁷ and R ⁸ are each independently hydrogen atom or a methyl group,, R ⁹ is consequent And particularly preferably a hexyl group or a phenyl group.

The polymer chain (B) may have only one type of ring structure represented by the formula (3), or may have two or more types.

Among the ring structures described above, when a copolymer (P) or a resin composition containing the same is applied to an optical film, good surface hardness, solvent resistance, adhesion, barrier properties, and optical properties are imparted. In view of the above, the ring structural unit of the polymer chain (B) preferably contains a lactone ring structure and / or a maleimide structure. When the optical film is a retardation film, it is more preferable that the ring structural unit of the polymer chain (B) contains a lactone ring structure from the viewpoint of imparting a positive retardation and excellent stability of the retardation characteristics.

The polymer chain (B) may further have units derived from other unsaturated monomers. The other unsaturated monomer is not particularly limited as long as it is a compound having a polymerizable double bond. For example, vinyl esters such as vinyl acetate and vinyl propionate; styrene, vinyl toluene, methoxy styrene, α-methyl styrene Aromatic vinyl compounds such as 2-vinylpyridine; vinylsilanes such as vinyltrimethoxysilane and γ- (meth) acryloyloxypropylmethoxysilane. For example, if the polymer chain (B) has a unit derived from an aromatic vinyl monomer, it becomes easy to adjust the refractive index and retardation characteristics of the copolymer (P). For details of the aromatic vinyl monomer, refer to the description of the aromatic vinyl monomer of the polymer block (a2). In addition, when a polymer chain (B) is formed from 2 or more types of monomer components, it is preferable that a polymer chain (B) is a random copolymer.

The copolymer (P) has a content ratio of units derived from (meth) acrylic acid ester in the polymer chain (B) of 45% by mass or more and 98% by mass or less. If the content ratio of the unit derived from (meth) acrylic acid ester in the polymer chain (B) is 45% by mass or more, generation of gelled product can be suppressed when the polymer chain (B) is formed by polymerization. It becomes easy to use a polymer (P) suitably for an optical use. In addition, the mechanical strength of the copolymer (P) can be easily increased. If the content rate of the unit derived from the (meth) acrylic acid ester in a polymer chain (B) is 98 mass% or less, the copolymer (P) excellent in heat resistance can be obtained. The content ratio of the unit derived from the (meth) acrylic acid ester in the polymer chain (B) is preferably 50% by mass or more, more preferably 55% by mass or more, further preferably 60% by mass or more, and 97% by mass or less. preferable.

The content of the ring structural unit in the polymer chain (B) is preferably 2% by mass or more, more preferably 3% by mass or more, further preferably 5% by mass or more, and preferably 50% by mass or less, and 45% by mass or less. Is more preferable, and 40 mass% or less is still more preferable. Thus, by adjusting the content ratio of the ring structural unit, it becomes easy to improve both the heat resistance and the mechanical strength of the copolymer (P) in a balanced manner. The content ratio of the ring structural unit described here means the content of the unit having a ring structure contained in the main chain of the polymer chain (B), and is represented by, for example, the above formulas (1) to (3). It means the content ratio of the structure.

In the polymer chain (B), the total content of the (meth) acrylic unit and the ring structural unit is preferably 90% by mass or more, more preferably 93% by mass or more, and further preferably 95% by mass or more. Thereby, it becomes easy to improve the transparency and heat resistance of the copolymer (P). Moreover, it is preferable that the total content rate of the unit derived from (meth) acrylic acid ester and a ring structure unit exists in such a range.

The polymer chain (B) is preferably grafted to the polymer chain (A). The polymer chain (B) may be bonded to a diene and / or olefin-derived unit of the polymer chain (A), and may be bonded to a unit other than the diene and / or olefin-derived unit of the polymer chain (A). It may be. In the former case, the polymer chain (B) may be directly bonded to the diene and / or olefin-derived unit of the polymer chain (A), or may be bonded via a linking group.

When the polymer chain (B) is directly bonded to a diene and / or olefin-derived unit of the polymer chain (A), the polymer chain (B) has a (meth) acryl unit or a ring structural unit of the polymer chain (A). It is preferably directly bonded to the unit derived from diene and / or olefin. The polymer chain (B) may be bonded to the carbon atom of the main chain of the unit derived from diene and / or olefin, and bonded to the carbon atom of the hydrocarbon group bonded as a substituent (side chain) to the main chain. You may do it. Thus, if the polymer chain (B) is bonded to the polymer chain (A), it becomes easy to obtain a copolymer (P) with less gelled product.

When the polymer chain (B) is bonded to the diene and / or olefin-derived unit of the polymer chain (A) via a linking group, the linking group includes an ester bond (—CO—O—), a urethane bond (—NH -CO-O-) and an ether bond (-O-) are preferable, and the linking group may further have a divalent organic group such as a methylene group or a hydroxymethylene group. Good.

When the polymer chain (B) is bonded to units other than the diene and / or olefin-derived units of the polymer chain (A), for example, the polymer chain (A) has a polymerizable functional group (polymerizable double bond). The polymer chain (B) is bonded to the polymerizable functional group of the unit, or the polymer chain (A) is other than a unit derived from a diene and / or olefin, and is an ester bond (—CO—O—) The polymer chain (B) may be bonded via a linking group such as a urethane bond (—NH—CO—O—) or an ether bond (—O—). The linking group may further have a divalent organic group such as a methylene group or a hydroxymethylene group.

Each aspect in which the polymer chain (B) described above is grafted to the polymer chain (A) will be described in detail in the description of the method for producing the copolymer (P) below.

The content ratio of the ring structural unit in the copolymer (P) is not particularly limited, but the content ratio of the ring structural unit in the copolymer (P) is, for example, preferably 1% by mass or more, and 3% by mass or more. More preferably, 5% by mass or more is more preferable, 60% by mass or less is preferable, 50% by mass or less is more preferable, and 40% by mass or less is more preferable. Thus, by adjusting the content ratio of the ring structural unit in the copolymer (P), it is easy to improve the heat resistance, transparency, moldability, mechanical strength, etc. of the copolymer (P) in a balanced manner. become.

When the copolymer (P) has a lactone ring structure as a ring structural unit of the polymer chain (B), the lactone in the copolymer (P) is used from the viewpoint of enhancing the heat resistance and transparency of the copolymer (P). The content of the ring structure is, for example, preferably 1% by mass or more, more preferably 3% by mass or more, further preferably 5% by mass or more, more preferably 60% by mass or less, more preferably 50% by mass or less, and 40% by mass. More preferred are: From the same viewpoint, when the copolymer (P) has a maleic anhydride structure and / or a maleimide structure as a ring structural unit of the polymer chain (B), the content ratio of these ring structures in the copolymer (P) Is, for example, preferably 1% by mass or more, more preferably 3% by mass or more, further preferably 5% by mass or more, more preferably 60% by mass or less, more preferably 50% by mass or less, and further preferably 40% by mass or less. When the copolymer (P) has a glutarimide structure and / or a glutaric anhydride structure as a ring structural unit of the polymer chain (B), the content ratio of these ring structures in the copolymer (P) is, for example, 1 % By mass or more is preferable, 3% by mass or more is more preferable, 5% by mass or more is more preferable, 60% by mass or less is preferable, 50% by mass or less is more preferable, and 40% by mass or less is more preferable.

The weight average molecular weight of the copolymer (P) is preferably 20,000 or more, more preferably 50,000 or more, further preferably 30,000 or more, still more preferably 50,000 or more, and particularly preferably 70,000 or more. Moreover, 1 million or less is preferable, 500,000 or less is more preferable, 300,000 or less is more preferable, 200,000 or less is still more preferable. By setting the weight average molecular weight of the copolymer (P) in such a range, the moldability of the copolymer (P) is improved and the strength of the obtained molded product is easily increased.

The weight average molecular weight of the copolymer (P) is preferably 1.1 times or more, more preferably 1.2 times or more, more preferably 1.3 times or more, more preferably 20 times the weight average molecular weight of the polymer chain (A). Is preferably 12 times or less, more preferably 10 times or less, still more preferably 7 times or less, and particularly preferably 5 times or less. Thereby, it becomes easy to give each characteristic of transparency, mechanical strength, and heat resistance with good balance to the copolymer (P).

The refractive index of the copolymer (P) is preferably a value close to the refractive index of the polymer chain (A), which makes it easy to ensure the transparency of the copolymer (P). Specifically, the difference between the refractive index of the copolymer (P) and the refractive index of the polymer chain (A) is preferably less than 0.1, more preferably 0.05 or less, and 0.02 or less. Further preferred. From the same viewpoint, the refractive index of the polymer chain (A) in the copolymer (P) and the refractive index of the polymer chain (B) are preferably close to each other. The difference between the refractive index and the refractive index of the polymer chain (B) is preferably less than 0.1, more preferably 0.05 or less, and even more preferably 0.02 or less.

The copolymer (P) preferably has a glass transition temperature of 100 ° C. or more and less than 100 ° C., respectively. A glass transition temperature of 100 ° C. or higher is referred to as “high temperature side glass transition temperature”, and a glass transition temperature of less than 100 ° C. is referred to as “low temperature side glass transition temperature”. The copolymer (P) may have a plurality of glass transition temperatures on the high temperature side, or may have a plurality of glass transition temperatures on the low temperature side. Since the copolymer (P) has a glass transition temperature on the high temperature side, the heat resistance of the copolymer (P) is increased, and when the copolymer (P) is molded into a film or the like, it is softened even at a high temperature. Without increasing the molding processability. When the copolymer (P) has a glass transition temperature on the low temperature side, the impact resistance of the copolymer (P) can be enhanced. The glass transition temperature on the high temperature side of the copolymer (P) is preferably 113 ° C or higher, more preferably 116 ° C or higher, and further preferably 120 ° C or higher. The glass transition temperature on the low temperature side of the copolymer (P) is preferably less than 50 ° C, more preferably less than 20 ° C, still more preferably less than 0 ° C, and even more preferably less than -20 ° C. .

The copolymer (P) can be produced by addition polymerization of the monomer component forming the polymer chain (B) to the polymer chain (A). Therefore, the method for producing the copolymer (P) is carried out in the presence of a polymer having units derived from diene and / or olefin (hereinafter referred to as “raw polymer (P1)”). It is preferable to have a step (polymerization step) for polymerizing the monomer component containing the monomer, and by this, the monomer component containing the (meth) acrylic monomer is added to the raw material polymer (P1). be able to. In this case, the monomer component containing the (meth) acrylic monomer is, for example, (1) a method of directly bonding to a diene and / or olefin-derived unit of the raw material polymer (P1), and (2) a raw material weight. A method in which the diene and / or olefin-derived unit of the polymer (P1) is bonded to the polymerizable functional group of the linking group in the side chain, or (3) other than the diene and / or olefin-derived unit of the starting polymer (P1) Can be addition-polymerized to the raw material polymer (P1) by any one of the methods of bonding to the polymerizable functional group of the unit in the side chain. In this case, the obtained copolymer is a graft copolymer. In the present specification, the “raw polymer (P1)” may be simply referred to as “polymer (P1)”.

The raw material polymer (P1) may have at least a unit derived from a diene and / or an olefin, and may further have a unit derived from another unsaturated monomer. Details of the units derived from the diene and / or olefin of the starting polymer (P1) and the units derived from other unsaturated monomers are described in detail for the units derived from the diene and / or olefin of the polymer chain (A) and other units. Reference is made to the description of units derived from saturated monomers. In the unit derived from diene and / or olefin, a part of hydrogen atoms may be chlorinated. The raw material polymer (P1) is a block copolymer having a polymer block (a1) having units derived from diene and / or olefin and a polymer block (a2) having units derived from other unsaturated monomers. The polymer block (a2) may be composed of units derived from an aromatic vinyl monomer. For these details, the description of the polymer chain (A) is referred to. In the method (2), the raw material polymer (P1) has a linking group having a polymerizable functional group in the side chain of the unit derived from diene and / or olefin. In the method (3), , Have a polymerizable functional group in the side chain of a unit other than the unit derived from diene and / or olefin.

The raw material polymer (P1) preferably has a weight average molecular weight of 10,000 or more, more preferably 50,000 or more, further preferably 10,000 or more, still more preferably 30,000 or more, and 500,000. The following is preferable, 300,000 or less is more preferable, 200,000 or less is more preferable, and 100,000 or less is even more preferable. By making the weight average molecular weight of raw material polymer (P1) into such a range, the moldability of copolymer (P) improves and it becomes easy to ensure the intensity | strength and transparency of copolymer (P). Moreover, generation | occurrence | production of a crosslinked body and a gel can be suppressed in the case of the polymerization reaction with the monomer component containing a (meth) acrylic-type monomer.

In the polymerization step, the raw material polymer (P1) may be used alone or in combination of two or more. In the latter case, it becomes easy to adjust the average molecular weight and the double bond amount as the resin composition.

In addition to the (meth) acrylic monomer, the monomer component used for forming the polymer chain (B) is a monomer that provides a cyclic structural unit. A polymer or the like can also be used. For example, when forming the polymer chain (B) having a maleimide structure in the main chain, it is preferable to use a monomer having a polymerizable double bond in the ring structure. Or when performing a ring structure formation process after a superposition | polymerization process, the monomer which can form a ring structure at the said process can also be used as a monomer component. In addition, other unsaturated monomers can be used. Details of these monomer components are the (meth) acrylic monomer that forms the polymer chain (B), the monomer that gives the ring structure of the polymer chain (B), and the polymer chain (B). Reference is made to the description of other unsaturated monomers.

Hereinafter, the above-mentioned methods (1) to (3) will be described in detail as to the method of addition polymerization of a monomer component containing a (meth) acrylic monomer to the raw material polymer (P1).

In the above method (1), in which the monomer component containing the (meth) acrylic monomer is directly bonded to the diene and / or olefin-derived unit of the raw material polymer (P1), the (meth) acrylic monomer The monomer component containing the body is bonded to the diene and / or olefin-derived unit of the raw material polymer (P1). In this case, it is preferable that the diene and / or olefin-derived unit of the raw material polymer (P1) has a double bond derived from the diene. The monomer component containing the (meth) acrylic monomer may be bonded to the diene-derived double bond of the main chain of the raw material polymer (P1), and bonded to the adjacent carbon atom of the double bond. May be. Alternatively, the polymer chain (B) is bonded to a diene-derived double bond bonded as a substituent (side chain) to the main chain of the starting polymer (P1), or bonded to an adjacent carbon atom of the double bond. It may be. In any case, the copolymer (P) obtained is such that the polymer chain (B) is directly bonded to the diene and / or olefin-derived units of the polymer chain (A). In this method, hydrogen having a high activity such as a vinyl position or an allylic position of a double bond (olefinic double bond) contained in a diene and / or olefin-derived unit of the raw material polymer (P1) is extracted. Preferably, this generates a radical at the site, and the monomer component forming the polymer chain (B) can be subjected to addition polymerization.

The monomer component containing the (meth) acrylic monomer of (2) above is used as a polymerizable functional group of a linking group that a diene and / or olefin-derived unit of the raw polymer (P1) has in the side chain. In the bonding method, the linking group has a polymerizable functional group (polymerizable double bond) and is bonded to a side chain of a unit derived from a diene and / or an olefin. In the obtained copolymer (P), the polymer chain (B) is bonded to the diene and / or olefin-derived unit of the polymer chain (A) via a linking group.

The linking group preferably has at least one selected from an ester bond, a urethane bond, and an ether bond in addition to a polymerizable functional group (polymerizable double bond), and is further divalent organic such as a methylene group or a hydroxymethylene group. It may have a group. The raw material polymer (P1) having such a linking group has a unit derived from a diene and / or olefin, and has a functional group that gives an ester bond, a urethane bond, or an ether bond (hereinafter referred to as “raw material weight”). A compound (P2) ”) and a compound having a functional group having reactivity with the functional group and having a polymerizable functional group (hereinafter referred to as“ radical polymerizable compound ”). Obtainable.

The functional group that provides an ester bond, a urethane bond, or an ether bond means a functional group that forms any one of these bonds by reaction with a radical polymerizable compound, and specifically includes a carboxyl group or an anhydride group thereof. , Epoxy group, hydroxyl group, isocyanate group and the like are preferable. In order to introduce these functional groups into the raw material polymer (P2), a polymer having units derived from diene and / or olefin (for example, the raw material polymer (P1) used in the production method of (1) above). And an unsaturated compound having these functional groups may be reacted with each other, and the reaction is usually performed using a radical initiator.

Examples of unsaturated compounds having a carboxyl group or its anhydride group include (meth) acrylic acid, fumaric acid, maleic acid and its anhydride, itaconic acid and its anhydride, crotonic acid and its anhydride, citraconic acid and its anhydride And unsaturated carboxylic acids such as products and anhydrides thereof.
Examples of unsaturated compounds having an epoxy group include glycidyl (meth) acrylate, mono and diglycidyl esters of maleic acid, mono and diglycidyl esters of itaconic acid, mono and diglycidyl esters of allyl succinic acid, glycidyl of p-styrene carboxylic acid Unsaturated carboxylic acid glycidyl esters such as esters; glycidyl ethers such as allyl glycidyl ether, 2-methylallyl glycidyl ether, styrene-p-glycidyl ether; p-glycidyl styrene; 3,4-epoxy-1-butene, 3,4 -Epoxy olefins such as epoxy-3-methyl-1-butene; vinylcyclohexene monoxide and the like.
Examples of unsaturated compounds having a hydroxyl group include hydroxyalkyl (meth) acrylates such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate and 2-hydroxybutyl (meth) acrylate; N-methylol (meta ) Acrylamide; 2-hydroxyethyl acrylate-6-hexanolide addition polymer; alkenyl alcohol such as 2-propen-1-ol; alkynyl alcohol such as 2-propyn-1-ol; hydroxy vinyl ether and the like.
Examples of the unsaturated compound having an isocyanate group include 2-isocyanatoethyl (meth) acrylate and methacryloyl isocyanate.

The radical polymerizable compound has a polymerizable functional group (polymerizable double bond) and a functional group having reactivity with a carboxyl group or an anhydride group thereof, an epoxy group, a hydroxyl group, or an isocyanate group. Examples of the reactive functional group include a hydroxyl group, an epoxy group, an isocyanate group, and a carboxyl group.

Examples of the radical polymerizable compound having a hydroxyl group as a reactive functional group include hydroxyalkyl (meth) acrylates such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and 2-hydroxybutyl (meth) acrylate. N-methylol (meth) acrylamide; 2-hydroxyethyl acrylate-6-hexanolide addition polymer; alkenyl alcohol such as 2-propen-1-ol; alkynyl alcohol such as 2-propyn-1-ol; Can be mentioned.
Examples of the radical polymerizable compound having an epoxy group as a reactive functional group include glycidyl (meth) acrylate, mono- and diglycidyl esters of maleic acid, mono- and diglycidyl esters of itaconic acid, mono- and diglycidyl esters of allyl succinic acid, p Glycidyl esters of unsaturated carboxylic acids such as glycidyl esters of styrene carboxylic acids; glycidyl ethers such as allyl glycidyl ether, 2-methylallyl glycidyl ether, styrene-p-glycidyl ether; p-glycidyl styrene; 3,4-epoxy- Examples thereof include epoxy olefins such as 1-butene and 3,4-epoxy-3-methyl-1-butene; vinylcyclohexene monooxide and the like.
Examples of the radical polymerizable compound having an isocyanate group as a reactive functional group include 2-isocyanatoethyl (meth) acrylate and methacryloyl isocyanate.
Examples of the radical polymerizable compound having a carboxyl group as a reactive functional group include unsaturated acids such as (meth) acrylic acid; carboxyalkyl vinyl ethers such as carboxyethyl vinyl ether and carboxypropyl vinyl ether.

When the functional group of the raw material polymer (P2) is a carboxyl group or an anhydride thereof, a hydroxyl group, an epoxy group, and an isocyanate group are preferably shown as the reactive functional group of the radical polymerizable compound. Among these, a radically polymerizable compound having a hydroxyl group is particularly preferable. In this case, the raw material polymer (P1) obtained by the reaction between the raw material polymer (P2) and the radical polymerizable compound has a linking group having a polymerizable functional group and an ester bond in the side chain.

When the functional group of the raw material polymer (P2) is an epoxy group, a carboxyl group and a hydroxyl group are preferably shown as the reactive functional group of the radical polymerizable compound. Of these, radically polymerizable compounds having a carboxyl group are particularly preferred. In this case, the raw material polymer (P1) obtained by the reaction between the raw material polymer (P2) and the radical polymerizable compound has a polymerizable functional group and an ester bond (specifically, —CH (OH) —CH ₂ —OCO). A linking group having a divalent organic group represented by-in the side chain.

When the functional group of the raw material polymer (P2) is a hydroxyl group, an isocyanate group, a carboxyl group and an epoxy group are preferably shown as the reactive functional group of the radical polymerizable compound. Among these, a radically polymerizable monomer having an isocyanate group is particularly preferable. In this case, the raw material polymer (P1) obtained by the reaction of the raw material polymer (P2) and the radical polymerizable compound has a linking group having a polymerizable functional group and a urethane bond in the side chain.

When the functional group of the raw material polymer (P2) is an isocyanate group, a hydroxyl group and a carboxyl group are preferably shown as the reactive functional group of the radical polymerizable compound. Among these, a radical polymerizable monomer having a hydroxyl group is particularly preferable. In this case, the raw material polymer (P1) obtained by the reaction of the raw material polymer (P2) and the radical polymerizable compound has a linking group having a polymerizable functional group and a urethane bond in the side chain.

Examples of the raw material polymer (P1) that can be used in the production method (2) include LIR UC-102M and UC-203, which are polyisoprenes having a methacryloyl group and an ester bond in the side chain (both manufactured by Kuraray Co., Ltd.) Etc.

The production method of the above (3) of the copolymer (P) will be described. The monomer component containing the (meth) acrylic monomer of (3) above is used as a polymerizable functional group having units other than the diene and / or olefin-derived unit in the raw polymer (P1) in the side chain. In the bonding method, a diene and / or olefin and an unsaturated monomer having a polymerizable functional group (polymerizable double bond) are copolymerized, or the diene and / or olefin and a carboxyl group or an anhydride thereof. The raw material is copolymerized with an unsaturated monomer having a functional group having a group, epoxy group, hydroxyl group, or isocyanate group, and further reacted with the radical polymerizable compound having the reactive functional group described above. A polymer (P1) can be obtained. Alternatively, a (co) polymer having a diene and / or olefin-derived unit is polymerized with an unsaturated monomer having a polymerizable functional group (polymerizable double bond), or a diene and / or olefin-derived unit. A radical having a reactive functional group as described above by polymerizing a (co) polymer having a carboxyl group or an anhydride group thereof, an epoxy group, a hydroxyl group, or an isocyanate group with an isocyanate group You may obtain a raw material polymer (P1) by making it react with a polymeric compound. The copolymer (P) is obtained by polymerizing the monomer component containing the (meth) acrylic monomer in the presence of the raw material polymer (P1) thus obtained. The resulting copolymer (P) has the polymer chain (B) bonded to a unit other than the diene and / or olefin-derived unit of the polymer chain (A).

When the (co) polymer having a diene and / or olefin or a unit derived therefrom is polymerized with an unsaturated monomer having a polymerizable functional group, the unsaturated monomer having a polymerizable functional group is , Polyfunctional (meth) acrylates, polyfunctional (meth) acrylic compounds such as vinyl ether group-containing (meth) acrylates, allyl group-containing (meth) acrylates, polyfunctional vinyl ethers, polyfunctional allyl compounds, polyfunctional aromatic vinyls, etc. Is mentioned.

Examples of the polyfunctional (meth) acrylate include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, hexanediol di (meth) acrylate, and bisphenol A alkylene oxide di (meth). Examples include acrylate, trimethylolpropane tri (meth) acrylate, 2,2 ′-[oxybis (methylene)] bisacrylic acid, dialkyl-2,2 ′-[oxybis (methylene)] bis-2-propenoate, and the like.
Examples of the vinyl ether group-containing (meth) acrylate include 2-vinyloxyethyl (meth) acrylate, 4-vinyloxybutyl (meth) acrylate, 2- (vinyloxyethoxy) ethyl (meth) acrylate, and the like.
Examples of allyl group-containing (meth) acrylates include allyl (meth) acrylate, methyl α-allyloxymethyl acrylate, stearyl α-allyloxymethyl acrylate, α-allyloxymethyl acrylate 2-decyltetradecyl acrylate, etc. Is mentioned.
Examples of the polyfunctional vinyl ether include ethylene glycol divinyl ether, diethylene glycol divinyl ether, polyethylene glycol divinyl ether, hexanediol divinyl ether, bisphenol A alkylene oxide divinyl ether, trimethylolpropane trivinyl ether, and the like.
Examples of polyfunctional allyl compounds include ethylene glycol diallyl ether, diethylene glycol diallyl ether, polyethylene glycol diallyl ether, hexanediol diallyl ether, bisphenol A alkylene oxide diallyl ether, trimethylolpropane triallyl ether, ditrimethylolpropane tetraallyl ether, and the like. Polyfunctional allyl ethers; polyfunctional allyl group-containing isocyanurates such as triallyl isocyanurate; polyfunctional allyl esters such as diallyl phthalate and diallyl diphenate; bisallyl nadiimide compounds; bisallyl nadiimide compounds and the like .
Examples of the polyfunctional aromatic vinyl include divinylbenzene.

An unsaturated monomer having a functional group having a carboxyl group or an anhydride group thereof, an epoxy group, a hydroxyl group, or an isocyanate group, and a (co) polymer having a diene and / or olefin, or a unit derived therefrom; In the case of polymerization, the resulting polymer (hereinafter referred to as “raw polymer (P3)”) has units derived from diene and / or olefin, and units other than units derived from diene and / or olefin. , A functional group having a carboxyl group or an anhydride group thereof, an epoxy group, a hydroxyl group, or an isocyanate group is bonded to the side chain of the other unit. Examples of the raw material polymer (P3) include an ethylene- (meth) acrylic acid copolymer, an ethylene-2-hydroxyethyl (meth) acrylate copolymer, an ethylene-glycidyl (meth) acrylate copolymer, and an ethylene-polyethylene. Glycol mono (meth) acrylate copolymer, ethylene-vinyl acetate- (meth) acrylic acid copolymer, ethylene-ethyl (meth) acrylate- (anhydrous) maleic acid copolymer, ethylene-vinyl acetate- (anhydrous) maleic Acid copolymer, ethylene-vinyl acetate-2-hydroxyethyl (meth) acrylate copolymer, ethylene-vinyl acetate-glycidyl (meth) acrylate copolymer, ethylene-vinyl acetate-polyethylene glycol mono (meth) acrylate copolymer Polymer, ethylene-vinyl acetate copolymer partial ken Thing, and the like. Among these, an ethylene- (meth) acrylic acid copolymer, an ethylene-ethyl (meth) acrylate- (anhydrous) maleic acid copolymer, and an ethylene-vinyl acetate-glycidyl (meth) acrylate copolymer are preferable.

The raw material polymer (P1) is obtained by reacting the raw material polymer (P3) with the radical polymerizable compound having the reactive functional group described above. For the details of the functional group of the raw material polymer (P3) and the reactive functional group of the radical polymerizable compound, these explanations in the method (2) are referred to.

In the reaction between the raw material polymer (P2) and the radical polymerizable compound in the method (2), or the reaction between the raw material polymer (P3) and the radical polymerizable compound in the method (3), the raw material polymer ( The reactive functional group of the radical polymerizable compound is preferably blended so as to be 0.1 to 10 equivalents per 1 equivalent of the functional group in P2) or the raw material polymer (P3) and reacted. Thereby, the yield of the finally obtained copolymer (P) can be increased.

The above reaction is preferably performed in a suitable organic solvent, and examples of the organic solvent include toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, butyl acetate, cellosolve acetate and the like. The reaction temperature is usually 20 ° C. to 150 ° C., preferably 50 ° C. to 120 ° C.

The reaction between the raw material polymer (P2) or the raw material polymer (P3) and the radical polymerizable compound is preferably performed in the presence of a catalyst. As the catalyst, acid or basic compounds such as sulfuric acid, paratoluenesulfonic acid, zinc chloride, pyridine, triethylamine, dimethylbenzylamine and the like can be used in the esterification reaction, and dibutyltin laurate and the like in the urethanization reaction. Can be used.

In the reaction, in order to prevent the formation of a homopolymer of a vinyl monomer, it is also preferable to react in an oxygen or air atmosphere and to add a suitable amount of a polymerization inhibitor such as hydroquinone, hydroquinone monomethyl ether, phenothiazine or the like to the reaction system. .

In the above methods (1) to (3), a (meth) acrylic monomer is contained in the presence of the raw material polymer (P1) obtained as described above (polymerization is carried out in the ring structure as necessary). The copolymer (P) can be obtained by polymerizing the monomer component (which further includes a monomer having an ionic double bond). Preferably, the copolymer (P) is obtained by graft polymerization of a monomer component containing a (meth) acrylic monomer to the raw material polymer (P1). The amount of each monomer component containing the (meth) acrylic monomer is such that the content ratio of units derived from the (meth) acrylic acid ester in the finally obtained polymer chain (B) is within a desired range. Adjust as appropriate. From the point that it is easy to suppress the formation of the gelled product in the polymerization step, the monomer component containing the (meth) acrylic monomer in the presence of the raw material polymer (P1) is prepared by the method (1). Polymerization is preferred. In the methods (2) and (3), the generation of gelled products can be suppressed by controlling the polymerization reaction such as setting the polymerization reaction time short.

The polymerization of the monomer component can be performed using a known polymerization method such as a bulk polymerization method, a solution polymerization method, an emulsion polymerization method, a suspension polymerization method, etc., but a solution polymerization method is preferably used. If the solution polymerization method is used, it is possible to suppress the entry of minute foreign matters into the copolymer (P), and the copolymer (P) can be suitably applied to optical materials and the like.

As the polymerization method, for example, either a batch polymerization method or a continuous polymerization method can be used. During the polymerization, the monomer components may be charged all at once or added in portions.

The polymerization solvent can be appropriately selected according to the composition of the monomer component, and an organic solvent used in a normal radical polymerization reaction can be used. Specifically, aromatic hydrocarbons such as toluene, xylene, and ethylbenzene; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; ethers such as tetrahydrofuran, dioxane, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, and anisole; acetic acid Esters such as ethyl, butyl acetate, propylene glycol monomethyl ether acetate, 3-methoxybutyl acetate; cellosolves such as methyl cellosolve, ethyl cellosolve, butyl cellosolve; alcohols such as methanol, ethanol, isopropanol, n-butanol; acetonitrile, pro Nitriles such as pionitrile, butyronitrile, benzonitrile; chloroform; dimethyl sulfoxide, etc. It is. These solvents may use only 1 type and may use 2 or more types together.

The polymerization reaction between the raw material polymer (P1) and the monomer component is preferably performed in the presence of a polymerization catalyst (polymerization initiator). Examples of the polymerization catalyst include 2,2′-azobisisobutyronitrile, 2,2′-azobis (2-amidinopropane) dihydrochloride, dimethyl-2,2′-azobis (2-methylpropio). Nate), 4,4′-azobis (4-cyanopentanoic acid) and the like; persulfates such as potassium persulfate; cumene hydroperoxide, diisopropylbenzene hydroperoxide, di-t-butyl peroxide, lauroyl Peroxide, benzoyl peroxide, t-butylperoxyisopropyl carbonate, t-amylperoxy-2-ethylhexanoate, t-amylperoxyoctoate, t-amylperoxyisononanoate, t-amylperoxy Isopropyl carbonate, t-amyl peroxy 2-ethyl f Organic peroxides such as sill carbonate can be used. These may use only 1 type and may use 2 or more types together. In the method (1), it is preferable to use a polymerization catalyst having a strong hydrogen abstraction force, and it is preferable to use an organic peroxide as such a polymerization catalyst. The amount of the polymerization catalyst used is preferably 0.01 to 1 part by mass with respect to 100 parts by mass of the monomer component, for example.

About each usage-amount of a raw material polymer (P1) and a monomer component, a raw material polymer (P1) is 0.5 mass with respect to a total of 100 mass parts of a raw material polymer (P1) and a monomer component. Part or more, preferably 1 part by weight or more, more preferably 3 parts by weight or more, more preferably 50 parts by weight or less, more preferably 30 parts by weight or less, and still more preferably 20 parts by weight or less. The monomer component is preferably 50 parts by mass or more, more preferably 70 parts by mass or more, still more preferably 80 parts by mass or more, based on 100 parts by mass of the total of the raw material polymer (P1) and the monomer component. 99 parts by mass or less is preferable, 98 parts by mass or less is more preferable, and 97 parts by mass or less is more preferable.

The concentration of the raw material polymer (P1) in the reaction solution is preferably 1% by mass or more, more preferably 3% by mass or more, more preferably 5% by mass or more, more preferably 50% by mass or less, and preferably 30% by mass or less. More preferred is 20% by mass or less. The concentration of the monomer component in the reaction solution is preferably 5% by mass or more, more preferably 10% by mass or more, and preferably 80% by mass or less, more preferably 70% by mass or less. The solvent concentration in the reaction solution is preferably 10% by mass or more, more preferably 20% by mass or more, more preferably 97% by mass or less, more preferably 95% by mass or less, further preferably 90% by mass or less, and 80% by mass. The following are even more preferred: During the polymerization reaction, a raw material polymer (P1), a monomer component, a polymerization catalyst, a reaction solvent, and the like can be appropriately added.

The polymerization reaction is preferably performed in an atmosphere of an inert gas such as nitrogen gas or in an air stream. In order to reduce the residual monomer, an azobis compound and a peroxide may be used in combination as a polymerization initiator. The reaction temperature is preferably 50 ° C to 200 ° C. The reaction time may be appropriately adjusted while observing the degree of progress of the copolymerization reaction and the degree of formation of the gelled product. For example, the reaction time is preferably 1 to 20 hours.

By the above polymerization step, a copolymer in which a polymer chain containing a unit derived from a (meth) acrylic monomer is bonded to the polymer chain (A) is obtained. In the polymerization step, when a (meth) acrylic monomer and a monomer having a polymerizable double bond in the ring structure (for example, maleic anhydride or maleimide) are used as the monomer component, A copolymer (P) in which a polymer chain (B) having an acrylic unit and a ring structural unit (maleic anhydride structure, maleimide structure) is bonded to the polymer chain (A) is obtained.

On the other hand, when obtaining a copolymer (P) having a lactone ring structure, a glutaric anhydride structure, or a glutarimide structure as a ring structural unit of the polymer chain (B), a ring structure forming step is performed following the polymerization step. It is preferable. In the ring structure forming step, a ring structure is formed in the main chain of the polymer chain having the (meth) acryl unit formed in the polymerization step. Specifically, a substituent of the adjacent (meth) acryl unit of the polymer chain having a (meth) acryl unit formed in the polymerization step is subjected to a condensation reaction to form a ring structure in the main chain of the polymer chain. The condensation reaction includes an esterification reaction, an acid anhydride reaction, an amidation reaction, an imidation reaction, and the like. For example, a glutaric anhydride structure can be formed by acid anhydrideizing two carboxylic acid groups of adjacent (meth) acryl units, and a glutarimide structure can be formed by imidization. When one of adjacent (meth) acrylic units has a protic hydrogen atom-containing group such as a hydroxyl group or an amino group, the protic hydrogen atom-containing group of the one (meth) acrylic unit and the other ( A lactone ring structure can be formed by condensing with a carboxylic acid group of a (meth) acryl unit.

In the ring structure forming step, the condensation reaction of adjacent (meth) acryl units is preferably performed in the presence of a catalyst (cyclization catalyst). As the cyclization catalyst, at least one selected from the group consisting of acids, bases and salts thereof can be used. The acid, base and salts thereof may be organic or inorganic and are not particularly limited. Among them, it is preferable to use an organic phosphorus compound as a catalyst for the cyclization reaction. By using an organophosphorus compound as a cyclization catalyst, the condensation reaction can be efficiently performed, and coloring of the resulting copolymer (P) can be reduced.

Examples of organophosphorus compounds that can be used as a cyclization catalyst include alkyl (aryl) phosphonous acids and monoesters or diesters thereof; dialkyl (aryl) phosphinic acids and esters thereof; alkyl (aryl) phosphonic acids and these. Monoesters or diesters; alkyl (aryl) phosphinic acids and their esters; phosphorous acid monoesters, diesters or triesters; methyl phosphate, ethyl phosphate, 2-ethylhexyl phosphate, octyl phosphate, isodecyl phosphate Lauryl phosphate, stearyl phosphate, isostearyl phosphate, phenyl phosphate, dimethyl phosphate, diethyl phosphate, di-2-ethylhexyl phosphate, diisodecyl phosphate, dilauryl phosphate, distearyl phosphate, Phosphoric monoesters, diesters or triesters such as diisostearyl phosphate, diphenyl phosphate, trimethyl phosphate, triethyl phosphate, triisodecyl phosphate, trilauryl phosphate, tristearyl phosphate, triisostearyl phosphate, triphenyl phosphate Examples include esters; mono-, di- or tri-alkyl (aryl) phosphines; alkyl (aryl) halogen phosphines; mono-, di- or tri-alkyl (aryl) phosphines; tetraalkyl (aryl) phosphonium halides. . These may use only 1 type and may use 2 or more types together. Among these, phosphoric acid monoesters or diesters are particularly preferable because of their high catalytic activity and low colorability. The amount of the cyclization catalyst used is preferably 0.001 to 1 part by mass with respect to 100 parts by mass of the copolymer obtained in the polymerization step, for example.

The reaction temperature in the ring structure formation step is preferably 50 ° C to 300 ° C. The reaction time may be appropriately adjusted while observing the degree of progress of the condensation reaction. For example, the reaction time is preferably 5 minutes to 6 hours.

By performing the polymerization step or the polymerization step and the ring structure formation step as described above, a resin solution containing the copolymer (P) can be obtained. The resin solution thus obtained is preferably filtered to remove foreign matters. Therefore, it is preferable that the manufacturing method of a copolymer (P) further has the process (filtration process) of filtering the resin solution obtained at the superposition | polymerization process or the ring structure formation process. By performing the filtration step, the amount of foreign matter in the copolymer (P) can be reduced. Therefore, when using the copolymer (P) as a raw material for the optical film, it is easy to obtain a highly transparent optical film with few surface irregularities and defects. In the present invention, since the amount of gelled product generated can be kept low in the polymerization step of the copolymer (P), the load on the filter in the filtration step is suppressed, and continuous filtration for a long time is possible. Therefore, a copolymer (P) with a high productivity and a small amount of foreign matter can be obtained. The filtration step can be carried out continuously following the polymerization step or the ring structure formation step.

As a filter used for filtration, a conventionally known filter can be used, and is not particularly limited. For example, a leaf disk filter, a candle filter, a pack disk filter, a cylindrical filter, and the like can be used. Among these, a leaf disk filter or a candle filter having a large effective filtration area is preferable.

The filtration accuracy (pore diameter) of the filter is usually, for example, 15 μm or less. When the copolymer (P) is used for an optical material such as an optical film, the filtration accuracy is preferably 10 μm or less and more preferably 5 μm or less from the viewpoint of reducing optical defects. The lower limit of the filtration accuracy is not particularly limited, and is, for example, 0.2 μm or more.

In the filtration step, the resin solution containing the copolymer (P) obtained in the polymerization step or the ring structure formation step may be filtered as it is, or may be diluted with a solvent or dispersed in a solvent and filtered. Good. If the copolymer (P) is solid, it may be melted and filtered with a sintered filter or the like, or dissolved or dispersed in a solvent and filtered. Filtration may be performed by heating or under pressure.

The solution temperature when the resin solution is subjected to filter filtration may be appropriately set according to the boiling point of the polymerization solvent and the like, for example, preferably not more than the boiling point of the polymerization solvent, more preferably not more than the boiling point of the polymerization solvent −10 ° C. On the other hand, if the temperature of the resin solution subjected to filter filtration is too low, the viscosity of the resin solution increases and the load on the device such as a gear pump may increase. Therefore, the temperature of the resin solution subjected to filter filtration is 50 ° C. The above is preferable, and 80 ° C or higher is more preferable.

The viscosity of the resin solution subjected to filter filtration is preferably 100 Pa · s or less, more preferably 80 Pa · s or less at 85 ° C. If the viscosity of the resin solution used for filter filtration is too high, the pressure loss during filter filtration may increase, and the filter unit may be damaged, or the filter filtration processing capacity may decrease due to increased viscosity. The pressure loss in filter filtration is preferably 2.5 MPa or less, more preferably in the range of 0.5 MPa to 2.0 MPa, and still more preferably in the range of 0.5 MPa to 1.5 MPa.

[2. Resin composition]
The present invention also provides a resin composition containing the copolymer (P) having the polymer chain (A) and the polymer chain (B) described above. The resin composition of the present invention is excellent in transparency, mechanical strength (for example, impact strength, etc.) and heat resistance, and has a good balance between them, and generates less gelled product during production. Hereinafter, the resin composition of the present invention is referred to as “resin composition (Q)”.

Resin composition (Q) may contain copolymer (P) as a resin component, or may contain another polymer as a resin component. When the resin composition (Q) contains another polymer, a (meth) acrylic polymer is preferably used as the other polymer, thereby increasing the homogeneity of the resin composition (Q), and the resin composition It becomes easy to improve the transparency and heat resistance of (Q).

The (meth) acrylic polymer only needs to have a unit derived from the (meth) acrylic monomer described in the polymer chain (B), and preferably described in the polymer chain (B). It has a unit derived from (meth) acrylic acid ester. The (meth) acrylic polymer may have units derived from other unsaturated monomers described in the polymer chain (B). The (meth) acrylic polymer is contained in the polymer chain (B) of the copolymer (P) from the viewpoint of increasing the compatibility with the copolymer (P) in the resin composition (Q) (meta) It is more preferable to have a unit derived from an acrylic monomer.

The (meth) acrylic polymer preferably has a ring structure, and more preferably has a ring structure in the main chain. When the resin composition (Q) contains a (meth) acrylic polymer having a ring structure in the main chain, the heat resistance of the resin composition (Q) can be increased. The ring structure of the main chain of the (meth) acrylic polymer includes a lactone ring structure, a cyclic imide structure (eg, a maleimide structure, a glutarimide structure, etc.), and a cyclic anhydride structure (eg, a maleic anhydride structure, a glutaric anhydride). And the like, and the details of these ring structures are referred to the description of the ring structure of the polymer chain (B). Especially, it is preferable that a (meth) acrylic-type polymer has the same ring structure as the ring structure which the polymer chain (B) of a copolymer (P) has in a principal chain.

The (meth) acrylic polymer preferably has a (meth) acryl unit contained in the polymer chain (B) of the copolymer (P) and a ring structural unit contained in the polymer chain (B). If the resin composition (Q) contains such a (meth) acrylic polymer, the compatibility with the copolymer (P) increases, and the transparency and heat resistance of the resin composition (Q) are increased. The resin composition (Q) can be easily prepared.

In 100% by mass of the solid content of the resin composition (Q), the content of the copolymer (P) is preferably 1% by mass or more, more preferably 2% by mass or more, further preferably 3% by mass or more, and 5% by mass. % Or more is even more preferable, which makes it easier to increase the mechanical strength of the resin composition (Q). The upper limit of the content ratio of the copolymer (P) in the resin composition (Q) is not particularly limited, and the resin composition (Q) may be composed only of the copolymer (P). In (Q), the content of the copolymer (P) may be 90% by mass or less, 70% by mass or less, 50% by mass or less, 40% by mass or less, or 30% by mass or less. . When the resin composition (Q) contains a solvent, the solid content of the resin composition (Q) means the amount of the resin composition (Q) excluding the solvent.

In 100 mass% of the solid content of the resin composition (Q), the content of the polymer chain (A) of the copolymer (P) is preferably 0.5 mass% or more, more preferably 1 mass% or more, and 3 mass%. % Or more is more preferable, 50 mass% or less is preferable, 30 mass% or less is more preferable, and 20 mass% or less is further more preferable. If the content rate of the polymer chain (A) in a resin composition (Q) is 0.5 mass% or more, it will become easy to raise the mechanical strength of a resin composition (Q). If the content rate of the polymer chain (A) in a resin composition (Q) is 50 mass% or less, it will become easy to improve transparency and heat resistance of a resin composition (Q). The content ratio of the polymer chain (A) can be determined, for example, by ¹ H-NMR.

When the resin composition (Q) contains a (meth) acrylic polymer, the content of the (meth) acrylic polymer in the solid content of 100% by mass of the resin composition (Q) is 1% by mass or more. Preferably, 20 mass% or more is more preferable, 30 mass% or more is further preferable, 99 mass% or less is preferable, 95 mass% or less is more preferable, and 90 mass% or less is further preferable.

In the solid content of 100% by mass of the resin composition (Q), the total content of the copolymer (P) and the (meth) acrylic polymer is preferably 50% by mass or more, more preferably 70% by mass or more, and 80 More preferably, it is more preferably 90% by weight or more. The upper limit of the content ratio of the copolymer (P) and the (meth) acrylic polymer in the resin composition (Q) is not particularly limited, and the resin composition (Q) is substantially composed of the copolymer (P). For example, the total content of the copolymer (P) and the (meth) acrylic polymer is 100% by mass in the solid content of the resin composition (Q). 99 mass% or more may be sufficient.

The resin composition (Q) may contain a polymer other than the (meth) acrylic polymer. Examples of such a polymer include polyethylene, polypropylene, ethylene-propylene polymer, poly (4 -Methyl-1-pentene) and other olefin polymers; halogen-containing polymers such as vinyl chloride and chlorinated vinyl resins; polystyrene, styrene-methyl methacrylate copolymer, styrene-acrylonitrile copolymer, acrylonitrile-butadiene -Styrene polymer such as styrene copolymer; Polyester such as polymer polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate; Polyamide such as nylon 6, nylon 66, nylon 610; Polyacetal; Polycarbonate; Polyphenylene oxide; Polypheny Polysulfide; Polyetheretherketone; Polysulfone; Polyethersulfone; Polyoxypentylene; Polyamideimide; Rubber polymer such as ABS resin and ASA resin blended with polybutadiene rubber and (meth) acrylic rubber; Can be mentioned.

The resin composition (Q) may contain various additives as long as the effects of the present invention are not impaired. Examples of additives include hindered phenol-based, phosphorus-based and sulfur-based antioxidants; light-resistant stabilizers, weather-resistant stabilizers, heat stabilizers and other stabilizers; reinforcing materials such as glass fibers and carbon fibers; ultraviolet rays Absorbers; near infrared absorbers; flame retardants such as tris (dibromopropyl) phosphate, triallyl phosphate, antimony oxide; phase difference adjusting agents such as phase difference increasing agents, phase difference reducing agents, phase difference stabilizers; anionic, Antistatic agents including cationic and nonionic surfactants; Colorants such as inorganic pigments, organic pigments, dyes; organic fillers and inorganic fillers; resin modifiers; organic fillers and inorganic fillers; . The content of each additive in the resin composition (Q) is preferably in the range of 0 to 5% by mass, more preferably 0 to 2% by mass.

Examples of ultraviolet absorbers include benzophenone compounds, salicylate compounds, benzoate compounds, triazole compounds, and triazine compounds, and known ultraviolet absorbers can be used. Examples of the benzophenone compounds include 2,4-dihydroxybenzophenone, 4-n-octyloxy-2-hydroxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone and the like. Examples of the silicate compound include pt-butylphenyl silicate. Examples of the benzoate compound include 2,4-di-t-butylphenyl-3 ', 5'-di-t-butyl-4'-hydroxybenzoate. Examples of triazole compounds include 2,2′-methylenebis [4- (1,1,3,3-tetramethylbutyl) -6- (2H-benzotriazol-2-yl) phenol], 2- (3,5 -Di-tert-butyl-2-hydroxyphenyl) -5-chlorobenzotriazole, 2- (2H-benzotriazol-2-yl) -p-cresol, 2- (2H-benzotriazol-2-yl) -4 , 6-Bis (1-methyl-1-phenylethyl) phenol, 2-benzotriazol-2-yl-4,6-di-tert-butylphenol, 2- [5-chloro (2H) -benzotriazole-2- Yl] -4-methyl-6-tert-butylphenol, 2- (2H-benzotriazol-2-yl) -4,6-di-tert-butylphenol, 2- (2H Benzotriazol-2-yl) -4- (1,1,3,3-tetramethylbutyl) phenol, and the like. Examples of triazine compounds include 2-mono (hydroxyphenyl) -1,3,5-triazine compounds, 2,4-bis (hydroxyphenyl) -1,3,5-triazine compounds, 2,4,6-tris ( Hydroxyphenyl) -1,3,5-triazine compound and the like. As commercially available ultraviolet absorbers, for example, “Tinuvin (registered trademark) 1577”, “Tinuvin (registered trademark) 460”, “Tinuvin (registered trademark) 477” (manufactured by BASF Japan), which are triazine-based ultraviolet absorbers, “Adekastab (registered trademark) LA-F70” (manufactured by ADEKA), “Adekastab (registered trademark) LA-31” (manufactured by ADEKA), which is a triazole-based ultraviolet absorber, and the like can be mentioned. Only one type of ultraviolet absorber may be used, or two or more types may be used in combination.

As the antioxidant, a compound having a radical scavenging function or a peroxide decomposition function can be used, and a known antioxidant can be used. Examples of antioxidants include hindered phenol antioxidants, hindered amine antioxidants, phosphorus antioxidants, sulfur antioxidants, benzotriazole antioxidants, benzophenone antioxidants, and hydroxylamines. Antioxidants, salicylic acid ester antioxidants, triazine antioxidants and the like can be mentioned. Among these antioxidants, hindered phenol antioxidants, hindered amine antioxidants, phosphorus antioxidants, and sulfur antioxidants are preferable. More preferably, a hindered phenolic antioxidant, a hindered amine antioxidant, and a phosphorus antioxidant are mentioned. Only one type of antioxidant may be used, or two or more types may be used in combination.

Examples of hindered phenol antioxidants include 2,4-bis [(laurylthio) methyl] -o-cresol, 1,3,5-tris (3,5-di-t-butyl-4-hydroxybenzyl), 1,3,5-tris (4-t-butyl-3-hydroxy-2,6-dimethylbenzyl) and the like.

Examples of hindered amine antioxidants include bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (N-methyl-2,2,6,6-tetramethyl-4-piperidyl) sebacate, N, N′-bis (2,2,6,6-tetramethyl-4-piperidyl) -1,6-hexamethylenediamine, 2-methyl-2- (2,2,6,6-tetramethyl-4 -Piperidyl) amino-N- (2,2,6,6-tetramethyl-4-piperidyl) propionamide, tetrakis (2,2,6,6-tetramethyl-4-piperidyl) (1,2,3,3) 4-butanetetracarboxylate, poly [(6- (1,1,3,3-tetramethylbutyl) imino-1,3,5-triazine-2,4-diyl) ((2,2,6,6 -Tetramethyl-4-piperi Le) imino) hexamethyl ((2,2,6,6-tetramethyl-4-piperidyl) imino)], etc. can be used.

Phosphorous antioxidants include tris (isodecyl) phosphite, tris (tridecyl) phosphite, phenyl isooctyl phosphite, phenyl isodecyl phosphite, phenyl di (tridecyl) phosphite, diphenyl isooctyl phosphite, diphenyl isodecyl Phosphite, diphenyltridecyl phosphite, triphenyl phosphite, tris (nonylphenyl) phosphite, 4,4 'isopropylidenediphenol alkyl phosphite, trisnonylphenyl phosphite, trisdinonylphenyl phosphite, other phosphites Oligomer type and polymer type compounds having a structure can also be used.

Examples of sulfur-based antioxidants include 2,2-thio-diethylenebis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 2,4-bis [(octylthio) methyl]- o-cresol, 2,4-bis [(laurylthio) methyl] -o-cresol, and the like. In addition, oligomer type or polymer type compounds having a thioether structure can also be used.

The weight average molecular weight of the resin composition (Q) is preferably 20,000 or more, more preferably 50,000 or more, further preferably 30,000 or more, still more preferably 50,000 or more, and particularly preferably 70,000 or more. Moreover, 1 million or less is preferable, 500,000 or less is more preferable, 300,000 or less is more preferable, 200,000 or less is still more preferable. By setting the weight average molecular weight of the resin composition (Q) in such a range, the moldability of the resin composition (Q) is improved and the strength of the obtained molded product is easily increased. The weight average molecular weight of the resin composition (Q) means a value in terms of polystyrene obtained by measuring the resin composition (Q) by gel permeation chromatography, and the resin composition (Q) is composed of the copolymer (P) and ( When it contains a (meth) acrylic polymer, the weight average molecular weight of the resin composition (Q) is the total weight average molecular weight of these plural types of polymers.

The weight average molecular weight of the resin composition (Q) is preferably 1.1 times or more, more preferably 1.2 times or more, and 1.3 times the weight average molecular weight of the polymer chain (A) of the copolymer (P). More preferably, 20 times or less is preferable, 12 times or less is more preferable, 10 times or less is more preferable, 7 times or less is further more preferable, and 5 times or less is particularly preferable. Thereby, it becomes easy to give each characteristic of transparency, mechanical strength, and heat resistance to the resin composition (Q) in a balanced manner.

The refractive index of the resin composition (Q) is preferably close to the refractive index of the polymer chain (A) of the copolymer (P), which makes it easy to ensure the transparency of the resin composition (Q). . Specifically, the difference between the refractive index of the resin composition (Q) and the refractive index of the polymer chain (A) of the copolymer (P) is preferably less than 0.1, more preferably 0.05 or less. Preferably, 0.02 or less is more preferable. From the same viewpoint, the refractive index of the resin composition (Q) is preferably a value close to the refractive index of the copolymer (P). Specifically, the refractive index and the refractive index of the resin composition (Q) The difference from the refractive index of the combined (P) is preferably less than 0.1, more preferably 0.05 or less, and further preferably 0.02 or less.

The resin composition (Q) preferably has a total light transmittance of 70% or more, more preferably 80% or more, and still more preferably 90% or more when an unstretched film having a thickness of 160 μm is formed. Moreover, it is preferable that haze is 5.0% or less, 3.0% or less is more preferable, and 1.0% or less is further more preferable. Regarding the internal haze, the internal haze per 100 μm thickness when it is an unstretched film is preferably 5.0% or less, more preferably 3.0% or less, and further 2.0% or less. Preferably, 1.0% or less is even more preferable.

The resin composition (Q) exhibits a sea-island structure when formed into an unstretched film having a thickness of 160 μm, and the island size in the structure is preferably 500 nm or less, more preferably 400 nm or less, and even more preferably 350 nm or less. Thereby, when a film is formed from the resin composition (Q), it becomes easy to obtain a highly transparent film. The lower limit of the island size of the sea-island structure is not particularly limited, and may be, for example, 10 nm or more, or 50 nm or more. Observation of the sea-island structure of the unstretched film formed from the resin composition (Q) is performed by a scanning electron microscope (STEM), and the specific measurement method is referred to the method described in the examples.

The resin composition (Q) preferably has a glass transition temperature of 100 ° C. or more and less than 100 ° C., respectively. A glass transition temperature of 100 ° C. or higher is referred to as “high temperature side glass transition temperature”, and a glass transition temperature of less than 100 ° C. is referred to as “low temperature side glass transition temperature”. The resin composition (Q) may have a plurality of glass transition temperatures on the high temperature side, or may have a plurality of glass transition temperatures on the low temperature side. Since the resin composition (Q) has a glass transition temperature on the high temperature side, the heat resistance of the resin composition (Q) is increased, and when the resin composition (Q) is molded into a film or the like, it is softened even at a high temperature. Without increasing the molding processability. When the resin composition (Q) has a glass transition temperature on the low temperature side, the mechanical strength and impact resistance of the resin composition (Q) can be increased. The glass transition temperature on the high temperature side of the resin composition (Q) is preferably 113 ° C. or higher, more preferably 116 ° C. or higher, further preferably 120 ° C. or higher, and the processing of the resin composition (Q). From the viewpoint of enhancing the properties, it is preferably less than 300 ° C, more preferably less than 200 ° C, and even more preferably less than 180 ° C. The glass transition temperature on the low temperature side of the resin composition (Q) is preferably −100 ° C. or higher, more preferably −90 ° C. or higher, further preferably −80 ° C. or higher, preferably lower than 50 ° C., more preferably lower than 30 ° C. Preferably, it is less than 10 ° C.

The resin composition (Q) preferably has an insoluble content in chloroform of 10% by mass or less, more preferably 8% by mass or less, and still more preferably 5% by mass or less. The copolymer (P) contained in the resin composition (Q) does not substantially contain a crosslinked structure or can be suppressed to a small amount even if it contains it, so that the insoluble content of the resin composition (Q) in chloroform The ratio of can be reduced. For this reason, the resin composition (Q) has a small amount of foreign matter contained therein. For example, when an optical film is formed from the resin composition (Q), there is little surface irregularities and defects, and a highly transparent film can be easily obtained. Obtainable. Moreover, when removing a foreign material from the resin composition, the load applied to the filter for removing a foreign material is reduced, and the production efficiency is improved.

On the other hand, for example, in the elastic organic fine particles having a core-shell structure disclosed in Japanese Patent Application Laid-Open No. 2008-242421, the organic fine particles are graft copolymers having a cross-linked structure, so that they are insoluble in chloroform. It will be a thing. Therefore, if a copolymer having such a crosslinked structure is used as a raw material for an optical film that requires high quality, it may cause foreign matters or defects of the film, or may become surface irregularities when the film is stretched, such as haze. This is not preferable because an appearance defect occurs. Further, the organic fine particles give a high load to the filter for removing foreign substances when removing foreign substances from the resin composition prior to film forming, and there is a concern that productivity may be reduced.

The insoluble content of the resin composition in chloroform is determined by the method described in the examples. Specifically, 1 g of the resin composition was added to 20 g of chloroform, and this was filtered through a Teflon (registered trademark) membrane filter having a pore diameter of 0.5 μm, and the amount of insoluble matter collected in the membrane filter was measured. The ratio of the insoluble content of the resin composition to chloroform is determined.

In the resin composition (Q), the foaming amount generated when heated at 290 ° C. for 20 minutes is preferably 20 pieces / g or less, more preferably 10 pieces / g or less, and further preferably 5 pieces / g or less. . Thereby, the external appearance of the molded object (for example, film etc.) at the time of heat-molding resin composition (Q) becomes favorable. The amount of foaming is measured using a melt indexer specified in JIS K 7210. The dried resin composition is filled in a melt indexer cylinder, held at 290 ° C. for 20 minutes, and then extruded into a strand. Then, the number of bubbles generated between the upper standard line and the lower standard line of the obtained strand is counted and expressed by the number of bubbles per 1 g of the resin composition.

The melt viscosity of the resin composition (Q) at 270 ° C. and 100 (/ second) measured based on JIS K 7199 (1999) is preferably 50 Pa · s or more, more preferably 100 Pa · s or more, and 5000 Pa · s. The following is preferable, and 1000 Pa · s or less is more preferable. If the melt viscosity of the resin composition (Q) is in such a range, the moldability of the resin composition (Q) is improved, and fish eyes and die lines are less likely to occur in the molded body. Appearance is improved.

The resin composition (Q) preferably has a breaking energy of 20 mJ or more, more preferably 24 mJ or more, and even more preferably 28 mJ or more when it is an unstretched film having a thickness of 160 μm. Thereby, when a film is formed from the resin composition (Q), it becomes easy to obtain a film having high mechanical strength. The breaking energy is determined by the method described in the examples.

The resin composition (Q) preferably has a trouser tear strength of 15 mJ or more, more preferably 18 mJ or more, and even more preferably 22 mJ or more when a stretched film having a thickness of 40 μm is used. Thereby, when a film is formed from the resin composition (Q), it becomes easy to obtain a film having high tear strength. Trouser tear strength is determined by the method described in the examples.

In the resin composition (Q), the number of folding resistance tests by the MIT folding resistance test when it is a stretched film having a thickness of 40 μm is preferably 1000 times or more, more preferably 1200 times or more, and more than 1350 times. Further preferred. Thereby, when forming a film from resin composition (Q), it becomes easy to obtain the high film which is hard to fracture | rupture. The MIT folding resistance test is performed by the method described in the examples.

The production method of the resin composition (Q) is not particularly limited, but when the copolymer (P) is polymerized, it is easy to polymerize the (meth) acrylic polymer together. In the production method of the copolymer (P) described above, the (meth) acrylic polymer corresponding to the polymer chain (B) of the copolymer (P) is simultaneously generated together with the copolymer (P). In this case, by not separating the copolymer (P) and the (meth) acrylic polymer, a resin composition (Q) containing the copolymer (P) and the (meth) acrylic polymer can be obtained. it can. In this case, the production method of the resin composition (Q) includes the polymerization step described in the production method of the copolymer (P), or the copolymer (P) and the main chain by the polymerization step and the ring structure formation step. A (meth) acrylic polymer having a ring structure is obtained.

The method for producing the resin composition (Q) is not limited to the above method, and the copolymer (P) may be isolated and mixed with another polymer to obtain the resin composition (Q). Further, in the above method for producing the copolymer (P), after completion of the graft copolymerization reaction to the copolymer (P1), another monomer is added to conduct a polymerization reaction to obtain a resin composition (Q). You may get Alternatively, with respect to the mixture of the copolymer (P) and the (meth) acrylic polymer obtained by the method for producing the copolymer (P), another polymer (for example, another (meth) (Acrylic polymer) may be added to obtain the resin composition (Q). When other polymers are added and mixed, they may be melt-kneaded. In this case, for example, a general apparatus such as a kneader or a multi-screw extruder can be used.

In the method for producing the resin composition (Q), the filtration step described above can be performed subsequent to the polymerization step or the ring structure formation step. By performing the filtration step, the amount of foreign matter in the resin composition (Q) can be reduced, and the resin composition (Q) is suitably applied to applications such as optical films that require high quality. Can do. For details of the filtration step, refer to the description of the filtration step in the production method of the copolymer (P).

[3. Molding of copolymer and resin composition]
The copolymer (P) and the resin composition (Q) can be used in a liquid state, or can be used as a cured product. In the latter case, the copolymer (P) and the resin composition (Q) can be heated and melted and molded into an arbitrary shape to form a molded body. What is necessary is just to set suitably the shape of a forming object according to a use, for example, plate shape, sheet shape, granular, powdery, lump shape, particle aggregate shape, spherical shape, elliptical spherical shape, lens shape, cubic shape, columnar shape, rod shape, Examples include a cone shape, a cylindrical shape, a needle shape, a fiber shape, a hollow fiber shape, and a porous shape. The molded body of the copolymer (P) and the resin composition (Q) can be used for injection molding, extrusion molding, vacuum molding, compression molding, blow molding and the like. Is preferably a powder of 1 μm to 1000 μm, a cylindrical or spherical pellet having a major axis of about 1 mm to 10 mm, or a mixture thereof.

The copolymer (P) and the resin composition (Q) can be formed into a film. As a film forming method, a known method such as a solution casting method (solution casting method), a melt extrusion method, a calendar method, a compression molding method, or the like can be used. Among these, the solution cast method and the melt extrusion method are preferable.

Examples of the solvent used in the solution casting method include chlorinated aliphatic hydrocarbons such as chloroform and dichloromethane; aromatic hydrocarbons such as toluene, xylene and benzene; methanol, ethanol, isopropanol, n-butanol, 2- Alcohols such as butanol; cellosolves such as methyl cellosolve, ethyl cellosolve and butyl cellosolve; ethers such as diethyl ether, dioxane and tetrahydrofuran; ketones such as acetone and cyclohexanone: esters such as ethyl acetate, propyl acetate and butyl acetate; Examples include dimethylformamide; dimethyl sulfoxide and the like. These may be used alone or in combination of two or more.

Examples of the apparatus for performing the solution casting method include a drum-type casting machine, a band-type casting machine, and a spin coater.

Examples of the melt extrusion method include a T-die method and an inflation method. The temperature (molding temperature) for melt extrusion molding of the film is preferably 150 ° C. or higher, more preferably 200 ° C. or higher, 350 ° C. or lower, and more preferably 300 ° C. or lower.

In the T-die method, a film wound around a roll is obtained by winding the film extruded from an extruder having a T-die attached to the tip onto a roll. At this time, stretching (uniaxial stretching) can be applied in the extrusion direction of the film by controlling the temperature and speed of winding.

In melt extrusion molding, it is preferable to use an extruder. The extruder preferably has a cylinder and a screw provided in the cylinder, and is provided with heating means. Depending on the number of screws, there are various types of extruders such as a single screw extruder, a twin screw extruder, and a multi-screw extruder, and any extruder may be used. The L / D value of the extruder (L is the length of the cylinder of the extruder, D is the inner diameter of the cylinder) is preferably 10 or more in order to sufficiently plasticize the resin composition and obtain a good kneaded state. The above is more preferable, 20 or more is more preferable, 100 or less is preferable, 80 or less is more preferable, and 60 or less is more preferable. When the L / D value is less than 10, the resin composition cannot be sufficiently plasticized and a good kneaded state may not be obtained. When the L / D value exceeds 100, excessive heat generation is applied to the resin composition, so that the components contained in the resin composition are easily decomposed.

The set temperature (heating temperature) of the cylinder of the extruder is preferably 200 ° C. or higher, more preferably 250 ° C. or higher, 350 ° C. or lower, more preferably 320 ° C. or lower. When setting temperature is less than 200 degreeC, there exists a possibility that the melt viscosity of a resin composition may become high too much and productivity of a film may fall. When setting temperature exceeds 350 degreeC, the component contained in a resin composition becomes easy to thermally decompose.

The extruder preferably has one or more open vent parts. By using such an extruder, the decomposition gas can be sucked from the open vent portion, and the amount of residual volatile components in the obtained film can be reduced. In order to suck the cracked gas from the open vent part, for example, the open vent part may be in a reduced pressure state, and the degree of pressure reduction at this time is preferably the pressure (absolute pressure) of the open vent part, preferably 1.3 hPa. As mentioned above, More preferably, it is 13.3 hPa or more, 931 hPa or less is preferable and 798 hPa or less is more preferable. When the pressure of an open vent part is higher than 931 hPa, a volatile component and the monomer component which generate | occur | produces by decomposition | disassembly of the polymer contained in a resin composition are easy to remain | survive in the obtained film. On the other hand, it is industrially difficult to keep the pressure of the open vent part lower than 1.3 hPa.

In the melt extrusion molding, it is preferable to filter the copolymer (P) or the resin composition (Q) in a molten state using a polymer filter, whereby the copolymer (P) or the resin composition ( Q) Foreign matter contained in the product can be removed. Thereby, when forming an optical film from a copolymer (P) or a resin composition (Q), the quantity of the optical defect in an optical film finally obtained, and the defect on an external appearance can be reduced.

The temperature of the melt extrusion molding is preferably, for example, 200 ° C. or higher, more preferably 250 ° C. or higher, 350 ° C. or lower, more preferably 320 ° C. or lower. If the temperature of melt extrusion molding is 200 ° C. or higher, the viscosity of the copolymer (P) or the resin composition (Q) is lowered, and the residence time in the polymer filter can be shortened. If the temperature of the melt extrusion molding is 350 ° C. or lower, for example, when the film is continuously formed, defects such as holes in the film, a flow pattern, and flow lines are hardly formed, and a film having a good appearance can be easily obtained.

The configuration of the polymer filter is not particularly limited. For example, a polymer filter in which a large number of leaf disk filters are arranged in a housing is preferably used. The filter medium of the leaf disk type filter should use any type of filter medium, such as a filter medium obtained by sintering a metal fiber non-woven fabric, a filter medium obtained by sintering metal powder, a filter medium obtained by laminating several metal meshes, or a hybrid type filter medium combining these. Can do. Especially, the filter medium which sintered the metal fiber nonwoven fabric is used preferably.

The filtration accuracy (pore diameter) of the polymer filter is not particularly limited. The filtration accuracy is usually 15 μm or less, preferably 10 μm or less, more preferably 5 μm or less, taking into account the size of the foreign matter to be removed. The lower limit of the filtration accuracy is not particularly limited, but the copolymer (P) and the resin composition (Q) are heated by increasing the residence time of the copolymer (P) and the resin composition (Q) in the polymer filter. In consideration of deterioration or a decrease in film productivity, 1 μm or more is preferable.

The shape of the polymer filter is not particularly limited. As a type of polymer filter, for example, it has a plurality of resin flow ports, an internal flow type having a resin flow path in the center pole, a cross section is in contact with the inner peripheral surface of the leaf disk filter at a plurality of vertices or faces, An outer flow type having a resin flow path on the outer surface of the center pole is exemplified. Especially, since there are few residence places of resin, an external flow type polymer filter is used preferably.

The residence time of the copolymer (P) or the resin composition (Q) in the polymer filter is preferably 20 minutes or less, more preferably 10 minutes or less, and even more preferably 5 minutes or less. In the melt filtration, the inlet pressure of the polymer filter and the outlet pressure of the filter are, for example, 3 MPa to 15 MPa and 0.3 MPa to 10 MPa, respectively. The pressure loss in melt filtration (pressure difference between the inlet pressure and the outlet pressure of the polymer filter) is preferably 1 MPa or more and 15 MPa or less. When the pressure loss is 1 MPa or less, the flow path through which the copolymer (P) and the resin composition (Q) pass through the polymer filter is likely to occur. The unevenness of the flow path causes the quality of the obtained film to deteriorate. When the pressure loss exceeds 15 MPa, the polymer filter tends to be damaged.

When melt-filtering the copolymer (P) or the resin composition (Q), it is preferable to stabilize the pressure in the polymer filter by installing a gear pump between the extruder and the polymer filter. Melt filtration using a polymer filter can be performed at any timing other than during melt extrusion molding.

When forming a film by the melt extrusion method, it may be a stretched film by stretching. By stretching, the mechanical strength of the film can be further improved. As a stretching method for obtaining a stretched film, a conventionally known stretching method can be applied. For example, uniaxial stretching such as free-width uniaxial stretching, constant-width uniaxial stretching; biaxial stretching such as sequential biaxial stretching and simultaneous biaxial stretching; A birefringent film in which molecular groups oriented in the stretching direction and the thickness direction are mixed by forming and heat-stretching the laminate and applying a shrinkage force in a direction perpendicular to the stretching direction to the film. Stretching to obtain. From the viewpoint of improving mechanical strength such as folding resistance of the film, biaxial stretching is preferably used. Furthermore, simultaneous biaxial stretching is preferably used from the viewpoint of improving mechanical strength such as folding resistance in two orthogonal directions in the film plane. Examples of the two orthogonal directions in the plane include a direction parallel to the slow axis in the film plane and a direction perpendicular to the slow axis in the film plane. The stretching conditions such as the stretching ratio, the stretching temperature, and the stretching speed may be appropriately set according to the desired mechanical strength and retardation value, and are not particularly limited.

Examples of the stretching apparatus include a roll stretching machine, a tenter-type stretching machine, and a small experimental stretching apparatus such as a tensile tester, a uniaxial stretching machine, a sequential biaxial stretching machine, and a simultaneous biaxial stretching machine. An apparatus can be used.

The stretching temperature is preferably around the highest glass transition temperature of the copolymer (P) or the resin composition (Q). Specifically, it is preferably performed within the range of the highest glass transition temperature−30 ° C. to the highest glass transition temperature + 50 ° C., more preferably the highest glass transition temperature−20 ° C. to the highest glass transition temperature + 45 ° C. Within the range, more preferably within the range of the highest glass transition temperature −10 ° C. to the highest glass transition temperature + 40 ° C. If the glass transition temperature is lower than −30 ° C., a sufficient draw ratio may not be obtained. If it is higher than the highest glass transition temperature + 50 ° C., resin flow occurs and it becomes difficult to perform stable stretching.

The draw ratio defined by the area ratio is preferably in the range of 1.1 to 30 times, more preferably in the range of 1.2 to 20 times, and still more preferably in the range of 1.3 to 10 times. In the case of stretching in a certain direction, the stretching ratio in one direction is preferably within a range of 1.05 to 10 times, more preferably within a range of 1.1 to 7 times, and even more preferably 1.2 to 5 times. Within range. By setting the draw ratio within such a range, effects such as improvement of the mechanical strength of the film accompanying drawing can be suitably obtained.

The stretching speed (one direction) is preferably in the range of 10 to 20,000% / min, more preferably in the range of 100 to 10,000% / min. When it is slower than 10% / min, it takes time to obtain a sufficient draw ratio, and the production cost tends to increase. If it is faster than 20,000% / min, the stretched film may be broken.

When applying a stretched film to an optical film, it is preferable to carry out a heat treatment (annealing) as necessary after stretching in order to stabilize the optical properties and mechanical properties of the optical film.

[4. Optical film)
Since the film formed from the copolymer (P) or the resin composition (Q) is excellent in transparency, it can be suitably used as an optical film. The optical film thus obtained is excellent in mechanical strength and heat resistance. The optical film may be a stretched film or an unstretched film. As an optical film, for example, an optical protective film (specifically, a protective film for substrates of various optical disks (VD, CD, DVD, MD, LD, etc.)), a polarizing plate provided in an image display device such as a liquid crystal display Examples include a polarizer protective film, a viewing angle compensation film, a light diffusion film, a reflection film, an antireflection film, an antiglare film, a brightness enhancement film, a conductive film for a touch panel, and a retardation film.

The thickness of the optical film is preferably 5 μm or more, more preferably 15 μm or more, and further preferably 20 μm or more from the viewpoint of increasing the strength of the optical film. On the other hand, from the viewpoint of reducing the thickness of the optical film, the thickness of the optical film is preferably 350 μm or less, more preferably 200 μm or less, and even more preferably 150 μm or less. The thickness of the optical film can be measured using, for example, a Digimatic micrometer manufactured by Mitutoyo Corporation.

The optical film preferably has a high light transmittance. For example, the total light transmittance is preferably 70% or more, more preferably 80% or more, and further preferably 90% or more.

The optical film preferably has a haze of 5.0% or less, more preferably 3.0% or less, and even more preferably 1.0% or less from the viewpoint of enhancing transparency. The internal haze is preferably 5.0% or less, more preferably 3.0% or less, still more preferably 2.0% or less, and even more preferably 1.0% or less.

The optical film preferably has an in-plane retardation Re of 0 nm to 1000 nm with respect to light having a wavelength of 589 nm, and a thickness direction retardation Rth of −1000 nm to 1000 nm with respect to the light. More preferably, Re is 0 nm to 100 nm, Rth is −100 nm to 100 nm, more preferably Re is 0 nm to 50 nm, Rth is −30 nm to 30 nm, particularly preferably Re is 0 nm to 10 nm, Rth is from −10 nm to 10 nm. An optical film exhibiting such an in-plane retardation Re and a thickness direction retardation Rth has good viewing angle characteristics and contrast characteristics, and can be suitably applied to image display devices such as liquid crystal displays. It becomes. The in-plane retardation Re is defined by Re = (nx−ny) × d, the thickness direction retardation Rth is defined by Rth = d × {(nx + ny) / 2−nz}, and nx is The refractive index in the slow axis direction in the film plane (the direction in which the refractive index is maximum in the film plane), ny is the refractive index in the direction perpendicular to nx in the film plane, nz is the refractive index in the film thickness direction, and d is Represents the thickness (nm) of the film.

The optical film may be composed only of a film formed from the copolymer (P) or the resin composition (Q), or may be composed of another optical material laminated on the film. By laminating other optical materials, optical properties can be further imparted to the optical film. Examples of other optical materials include a polarizing plate, a stretched oriented film made of polycarbonate, a stretched oriented film made of cyclic polyolefin, and the like.

Various functional coating layers may be provided on the surface of the optical film as necessary. Examples of the functional coating layer include an antistatic layer, an adhesive layer, an adhesive layer, an easy adhesion layer, an antiglare (non-glare) layer, an antifouling layer such as a photocatalyst layer, an antireflection layer, a hard coat layer, and an ultraviolet ray. Examples thereof include a shielding layer, a heat ray shielding layer, an electromagnetic wave shielding layer, and a gas barrier layer. Moreover, the optical adjustment layer for adjusting suitably the transmittance | permeability or reflectance of the incident light beam may be provided on the surface of the optical film.

The optical film of the present invention can be suitably used particularly for a polarizer protective film. The polarizer protective film is not particularly limited except that it contains a copolymer (P). When applying an optical film to a polarizer protective film, an optical film (polarizer protective film) may be provided on one or both sides of the polarizer to constitute a polarizing plate. The optical film (polarizer protective film) is preferably fixed to the polarizer directly or indirectly via another layer with an adhesive or a pressure-sensitive adhesive.

The type of the polarizer is not particularly limited. For example, a polarizer obtained by dyeing and stretching a polyvinyl alcohol film; a polyene polarizer such as dehydrated polyvinyl alcohol or dehydrochlorinated polyvinyl chloride; a multilayer laminate or a cholesteric liquid crystal is used. Reflective polarizers; polarizers made of thin-film crystal films, and the like. As an example of the structure of the polarizing plate, polyvinyl alcohol is dyed with a dichroic substance such as iodine or a dichroic dye and then uniaxially stretched to obtain a polarizer, and a polarizer protective film is provided on one or both sides of the polarizer. The structure provided with (optical film) is mentioned.

The optical film can also be used as a transparent conductive film by forming a transparent conductive layer on the surface. As the material constituting the transparent conductive layer, any material conventionally used as a conductive material in the field can be used. Specifically, an organic conductive compound; an organic conductive polymer; indium oxide; Metal oxides such as tin oxide, zinc oxide, indium-tin oxide (ITO), antimony-tin oxide (ATO), zinc-aluminum oxide, indium-zinc oxide (IZO); gold, silver, copper, Examples include metals such as palladium and aluminum.

The optical film of the present invention (for example, a polarizer protective film or a transparent conductive film) can be suitably used for an image display device. Examples of the image display device include a liquid crystal display device. For example, in the case of a liquid crystal display device, the image display unit can be configured to have the optical film of the present invention together with members such as a liquid crystal cell, a polarizing plate, and a backlight. Examples of the image display device other than the liquid crystal display device include an electroluminescence (EL) display panel, a plasma display panel (PDP), a field emission display (FED), a QLED, and a micro LED.

This application claims the benefit of priority based on Japanese Patent Application No. 2017-004468 filed on Jan. 13, 2017. The entire content of the specification of Japanese Patent Application No. 2017-004468 filed on January 13, 2017 is incorporated herein by reference.

Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples, but the present invention is not limited thereto. In the following description, “part” represents “part by mass” and “%” represents “% by mass” unless otherwise specified.

(1) Analysis method (1-1) Weight average molecular weight (Mw) and number average molecular weight (Mn)
The weight average molecular weight and the number average molecular weight were determined by gel conversion using gel permeation chromatography (GPC). The apparatus and measurement conditions used for the measurement are as follows.
-Measurement system: GPC system HLC-8220, manufactured by Tosoh Corporation
-Measurement side column configuration Guard column: TSK guard column Super HZ-L manufactured by Tosoh Corporation
Separation column: Tosoh Corporation, TSKgel SuperHZM-M 2 in series connection-Reference side column configuration Reference column: Tosoh, TSKgel SuperH-RC
-Developing solvent: chloroform (made by Wako Pure Chemical Industries, special grade)
-Solvent flow rate: 0.6 mL / min-Standard sample: TSK standard polystyrene (PS-oligomer kit, manufactured by Tosoh Corporation)

(1-2) Glass transition temperature (Tg)
The glass transition temperature was calculated | required based on JISK7121 (2012). Specifically, using a differential scanning calorimeter (Rigaku, Thermo plus EVO DSC-8230), a sample of about 10 mg was heated from room temperature to 300 ° C. (temperature increase rate 20 ° C./min) in a nitrogen gas atmosphere. From the DSC curve obtained in this way, the starting point method was used for evaluation. Α-alumina was used as a reference. The glass transition temperature of less than 40 ° C was measured using a differential scanning calorimeter (DSC-3500, manufactured by Netch Co., Ltd.), and the sample was heated from -100 ° C to 60 ° C (temperature increase rate: 10 ° C / min) in a nitrogen gas atmosphere. From the DSC curve obtained in this way, the starting point method was used for evaluation. An empty container was used as a reference.

(1-3) Monomer Reaction Rate The monomer reaction rate (conversion rate) is determined by measuring the amount of residual monomer in the polymerization reaction solution using gas chromatography (Shimadzu Corporation, GC-2014). It was.

(1-4) Gelation evaluation (filtration test)
The gelation of the resin composition was evaluated by a filter filtration test. If a 0.1 mass% chloroform solution of the resin composition is filtered using a plastic syringe with a filter attached to the tip (GL Science Co., Ltd., Chromatodisc 13N, pore size 0.45 μm), 2 mL of the total amount can be filtered. If the solution was clogged and 2 mL of the solution could not be filtered, it was evaluated as x.

(1-5) Chloroform-insoluble component 1 g of the resin composition was added to 20 g of chloroform, and this was filtered through a membrane filter (ADVANTEC, T050A047A) having a pore size of 0.5 μm, and the filtered membrane filter was dried. From the mass M ₀ (g) of the membrane filter before filtration and the mass M ₁ (g) of the membrane filter after filtration after filtration, the chloroform insoluble content of the resin composition was determined according to the following formula: chloroform insoluble content (mass%) ) = (M ₁ −M ₀ ) / 1 × 100.

(1-6) Breaking energy (falling ball test)
The breaking energy was obtained as follows. First, the resin composition was formed into a film (unstretched film) having a thickness of 160 μm by hot pressing. Next, a test of dropping a ball having a mass of 0.0054 kg from a certain height was carried out 10 times on this film, and the average value of the height (breaking height) when the film was broken was obtained. Specifically, when the height was set in several steps and the balls were dropped in order from the lowest height, the height at which the film was broken was obtained, and this was repeated 10 times to break the film. The height was obtained 10 times, and the average value was obtained as the breaking height. Whether or not the film was destroyed was judged by visually confirming whether or not the film was deformed after falling on the film. If deformation was seen, the film was considered broken. The breaking energy (E) was determined according to the following formula: breaking energy E (mJ) = mass of sphere (kg) × average breaking height (mm) × 9.8 (m / s ² ).

(1-7) Total Light Transmittance The resin composition was formed into a film by hot pressing to obtain a 160 μm-thick film (unstretched film), which was a haze meter (NDH-5000, manufactured by Nippon Denshoku Industries Co., Ltd.). ) To measure the total light transmittance.

(1-8) Internal haze The resin composition was hot press molded at 250 ° C. to produce a film (unstretched film) having a thickness of about 160 μm. Fill a quartz cell with 1,2,3,4-tetrahydronaphthalene (tetralin), immerse the produced film in it, and measure the haze using a haze meter (NDH-5000, manufactured by Nippon Denshoku Industries Co., Ltd.). The internal haze per 100 μm thickness was calculated according to the following formula: Internal haze per 100 μm thickness (%) = measured value obtained (%) × (100 μm / film thickness (μm)). The measurement was performed using three films, and the internal haze per 100 μm thickness was calculated from the average value.

(1-9) Dispersion state (observation of sea-island structure size by STEM)
A 160 μm-thick film (unstretched film) produced by hot press molding the resin composition at 250 ° C. was subjected to phase separation of the film using a scanning electron microscope (FE-SEM S-4800, manufactured by Hitachi High-Technologies Corporation). The dispersion state (sea-island structure) was observed. The measurement conditions were as follows: acceleration voltage 20 kV, emission current 5 μA or 10 μA, W.V. D. = 8 mm. The island size was calculated as an average value by measuring the maximum length of any 10 islands.

(1-10) MIT fold resistance test (fold strength)
The resin composition was hot press molded at 250 ° C. to obtain an unstretched film having a thickness of 160 μm. The obtained unstretched film was cut into a size of 96 mm × 96 mm, and using a sequential biaxial stretching machine (X-6S, manufactured by Toyo Seiki Seisakusho Co., Ltd.) at a temperature of Tg + 24 ° C. of the resin composition, 240 mm / min. A stretched film having a thickness of 40 μm was obtained by sequentially biaxially stretching the film at a stretching speed in the order of the machine direction (MD direction) and the transverse direction (TD direction) so that the draw ratio was doubled and cooling. The obtained stretched film was cut into a size of 90 mm × 15 mm to obtain a test piece, and was used in an atmosphere at a temperature of 23 ° C. and a relative humidity of 50% using a MIT folding resistance tester (BE-201, manufactured by Tester Sangyo Co., Ltd.). A load of 200 g was applied and the number of MIT folding resistance tests was measured according to JIS P 8115 (2001).

(1-11) Trouser tear strength (Tear strength)
The trouser tear strength was determined in accordance with JIS K 7128-1 (1998). Specifically, the stretched film obtained in accordance with the description in (1-10) above is cut into a size of 120 mm × 30 mm and allowed to stand for 1 hour or longer in an atmosphere at a temperature of 23 ° C. and a relative humidity of 50%. The test piece was tested using an autograph (manufactured by Shimadzu Corp., AGS-X) at a test speed of 200 mm / min. The average of the tearing force of 35 mm excluding 20 mm at the start of tearing and 5 mm before the end of tearing The value was calculated, and the average value of the five samples was taken as the measurement result.

(1-12) Retardation A stretched film obtained according to the description in (1-10) above was subjected to a condition with an incident angle of 40 ° using a fully automatic birefringence meter (KOBRA-WR, manufactured by Oji Scientific Instruments). Then, an in-plane retardation Re and a thickness direction retardation Rth for light having a wavelength of 590 nm were measured. The refractive index in the slow axis direction in the plane of the film is nx, the refractive index in the fast axis direction in the plane of the film is ny, the refractive index in the thickness direction of the film is nz, and the thickness of the film is d. The in-plane retardation Re and the thickness direction retardation Rth were determined from the equations.
In-plane retardation Re = (nx−ny) × d
Thickness direction retardation Rth = [(nx + ny) / 2−nz] × d

(2) Production of Resin Composition (2-1) Example 1: Preparation of Resin Composition (A-1) Polyisoprene anhydrous in a reactor equipped with a stirrer, temperature sensor, cooling pipe and nitrogen introduction pipe 3 parts of esterified product of maleic acid adduct and 2-hydroxyethyl methacrylate (Kuraray, UC-102M), 26 parts of methyl methacrylate (MMA), 1 part of methyl 2- (hydroxymethyl) acrylate (MHMA), 50 parts of toluene was charged as a polymerization solvent, and the temperature was raised to 105 ° C. through nitrogen. Thereafter, 0.09 part of t-amylperoxyisononanoate (manufactured by Arkema Yoshitomi Co., Ltd., Luperox (registered trademark) 570) was added as an initiator, and solution polymerization was carried out at 105 to 110 ° C. for 30 minutes. 0.01 parts of stearyl phosphate was added here as a cyclization catalyst and reacted for 10 minutes. As a result, a resin composition containing a lactone ring-containing (meth) acrylic polymer and a graft copolymer obtained by grafting the polymer chain onto a polyisoprene chain was obtained. The reaction rate of MMA calculated from the amount of residual monomers in the polymerization reaction solution was 16%, and the reaction rate of MHMA was 10%. The composition ratio (mass basis) of the (meth) acrylic polymer chain and the (meth) acrylic polymer bonded to the polyisoprene chain calculated from the reaction rate is MMA: MHMA = 97.7: 2.3. The content ratio of units derived from (meth) acrylic acid ester was 96.2% by mass, and the content ratio of ring structural units was 3.5% by mass. A part of the reaction solution was taken out and subjected to a filtration test. As a result, filtration could be suitably performed.
Next, 50 parts of methyl ethyl ketone (MEK) is added to the obtained reaction solution for dilution, and this is filtered through a PTFE (polytetrafluoroethylene) filter having a pore size of 10 μm, and then stirred in a large amount of methanol. Slowly added. At this time, the precipitated white solid was taken out and dried at 2.6 kPa and 80 ° C. for about 1 hour to remove the solvent, whereby the lactone ring-containing (meth) acrylic polymer and the polymer chain were grafted to the polyisoprene chain. A resin composition (A-1) containing a graft copolymer was obtained. The weight average molecular weight of the resin composition (A-1) was 138,000, the number average molecular weight was 38,000, and the chloroform-insoluble content was 2%.

(2-2) Example 2: Preparation of Resin Composition (A-2) In a reactor equipped with a stirrer, a temperature sensor, a cooling pipe, and a nitrogen introduction pipe, a maleic anhydride adduct of polyisoprene and 2-hydroxy 3 parts of esterified product with ethyl methacrylate (Kuraray Co., Ltd., UC-102M), 23 parts of methyl methacrylate (MMA), 3 parts of phenylmaleimide (PMI), and 50 parts of toluene as a polymerization solvent were charged with nitrogen through 105 parts. The temperature was raised to ° C. Thereafter, 0.09 part of t-amylperoxyisononanoate (manufactured by Arkema Yoshitomi Co., Ltd., Luperox (registered trademark) 570) was added as an initiator, and solution polymerization was carried out at 105 to 110 ° C. for 30 minutes. Thus, a resin composition containing a maleimide ring-containing (meth) acrylic polymer and a graft copolymer in which the polymer chain was grafted to a polyisoprene chain was obtained. The reaction rate of MMA calculated from the amount of residual monomers in the polymerization reaction solution was 14%, and the reaction rate of PMI was 21%. The composition ratio (mass basis) of the (meth) acrylic polymer chain and the (meth) acrylic polymer bonded to the polyisoprene chain calculated from the reaction rate is MMA: PMI = 83.6: 16.4. The content ratio of units derived from (meth) acrylic acid ester was 83.6% by mass, and the content ratio of ring structural units was 16.4% by mass. A part of the reaction solution was taken out and subjected to a filtration test. As a result, filtration could be suitably performed.
Next, 50 parts of methyl ethyl ketone (MEK) was added to the obtained reaction solution to dilute it, and after filtering through a PTFE filter having a pore size of 10 μm, it was slowly added to a large amount of methanol with stirring. At that time, the precipitated white solid was taken out, dried at 2.6 kPa and 80 ° C. for about 1 hour, and the solvent was removed, so that the maleimide ring-containing (meth) acrylic polymer and the polymer chain grafted to the polyisoprene chain. A resin composition (A-2) containing a graft copolymer was obtained. The resin composition (A-2) had a weight average molecular weight of 111,000, a number average molecular weight of 31,000, and a chloroform-insoluble content of 3%.

(2-3) Comparative Example 1: Preparation of Resin Composition (A-3) In a reactor equipped with a stirrer, a temperature sensor, a cooling pipe and a nitrogen introduction pipe, a maleic anhydride adduct of polyisoprene and 2-hydroxy 3 parts of an esterified product with ethyl methacrylate (Kuraray Co., Ltd., UC-102M), 27 parts of methyl methacrylate (MMA) and 50 parts of toluene as a polymerization solvent were charged, and the temperature was raised to 105 ° C. through nitrogen. Thereafter, 0.09 part of t-amylperoxyisononanoate (manufactured by Arkema Yoshitomi Co., Ltd., Luperox (registered trademark) 570) was added as an initiator, and solution polymerization was carried out at 105 to 110 ° C. for 30 minutes. As a result, a resin composition containing a methyl methacrylate polymer (PMMA) and a graft copolymer in which the polymer chain was grafted to a polyisoprene chain was obtained. The reaction rate of MMA calculated from the amount of residual monomer in the polymerization reaction solution was 16%.
Next, 50 parts of methyl ethyl ketone (MEK) was added to the obtained reaction solution for dilution, and then slowly added to a large amount of methanol with stirring. At this time, the precipitated white solid was taken out, dried at 2.6 kPa and 80 ° C. for about 1 hour, and the solvent was removed to remove methyl methacrylate polymer (PMMA) and the graft copolymer in which the polymer chain was grafted to the polyisoprene chain. A resin composition (A-3) containing a polymer was obtained. The weight average molecular weight of the resin composition (A-3) was 124,000, and the number average molecular weight was 31,000.

(2-4) Comparative Example 2: Synthesis of Resin Composition (B-1) In a reactor equipped with a stirrer, a temperature sensor, a cooling pipe, and a nitrogen introduction pipe, 48 parts of methyl methacrylate (MMA), 2- ( Hydroxymethyl) 2 parts of methyl acrylate (MHMA) and 50 parts of toluene as a polymerization solvent were charged, and the temperature was raised to 105 ° C. while passing nitrogen. Thereafter, 0.2 part of t-amyl peroxyisononanoate (manufactured by Arkema Yoshitomi, Luperox (registered trademark) 570) was added as an initiator, and solution polymerization was carried out at 105 to 110 ° C. for 180 minutes. Here, 0.01 part of stearyl phosphate was added as a cyclization catalyst and reacted for 1 hour, followed by heating at 240 ° C. for 1 hour in an autoclave. Thereby, a resin composition containing a lactone ring-containing (meth) acrylic polymer was obtained. The reaction rate of MMA calculated from the amount of residual monomers in the polymerization reaction solution was 82%, and the reaction rate of MHMA was 88%. The composition ratio (mass basis) of the lactone ring-containing (meth) acrylic polymer calculated from the reaction rate is MMA: MHMA = 95.7: 4.3, and the content ratio of units derived from (meth) acrylic acid ester is The content ratio of 93.1% by mass and the ring structural unit was 6.4% by mass.
Next, 50 parts of methyl ethyl ketone (MEK) was added to the obtained reaction solution for dilution, and then slowly added to a large amount of methanol with stirring. At this time, the precipitated white solid was taken out and dried at 2.6 kPa and 200 ° C. for about 1 hour to remove the solvent, whereby the resin composition (B-1) containing a lactone ring-containing (meth) acrylic polymer was obtained. Obtained. The weight average molecular weight of the resin composition (B-1) was 138,000 and the number average molecular weight was 57,000.

(2-5) Comparative Example 3: Preparation of Resin Composition (B-2) In a reactor equipped with a stirrer, a temperature sensor, a cooling pipe, and a nitrogen introduction pipe, 47 parts of methyl methacrylate (MMA), 3 parts of PMI, 50 parts of toluene was charged as a polymerization solvent, and the temperature was raised to 105 ° C. through nitrogen. Thereafter, 0.2 part of t-amyl peroxyisononanoate (manufactured by Arkema Yoshitomi, Luperox (registered trademark) 570) was added as an initiator, and solution polymerization was carried out at 105 to 110 ° C. for 180 minutes. Thereby, a resin composition containing a maleimide ring-containing (meth) acrylic polymer was obtained. The reaction rate of MMA calculated from the amount of residual monomers in the polymerization reaction solution was 85%, and the reaction rate of PMI was 82%. The composition ratio (mass basis) of the maleimide ring-containing (meth) acrylic polymer calculated from the reaction rate is MMA: PMI = 94.2: 5.8, and the content ratio of units derived from (meth) acrylic acid ester is The content ratio of 94.2% by mass and the ring structural unit was 5.8% by mass.
Next, 50 parts of methyl ethyl ketone (MEK) was added to the obtained reaction solution for dilution, and then slowly added to a large amount of methanol with stirring. At this time, the precipitated white solid was taken out, dried at 2.6 kPa and 200 ° C. for about 1 hour, and the solvent was removed, whereby a resin composition (B-2) containing a maleimide ring-containing (meth) acrylic polymer was obtained. Obtained. The weight average molecular weight of the resin composition (B-2) was 1290,000, and the number average molecular weight was 59,000.

(2-6) Example 3: Preparation of Resin Composition (C-1) 1 part of the resin composition (A-1) obtained in Example 1 and the resin composition (B-1) obtained in Comparative Example 2 9 parts was dissolved in 40 parts of MEK and mixed, and then dried at 2.6 kPa and 150 ° C. for about 1 hour to remove the solvent, thereby obtaining a resin composition (C-1). The weight average molecular weight of the resin composition (C-1) was 133,000, and the number average molecular weight was 59,000.

(2-7) Example 4: Preparation of Resin Composition (C-2) 1 part of the resin composition (A-2) obtained in Example 2 and the resin composition (B-2) obtained in Comparative Example 3 ) 9 parts, UV absorber (ADEKA, LA-31) 0.01 part, antioxidant (BASF, Irganox (registered trademark) 1010) 0.001 part, antioxidant (ADEKA) PEP-36) manufactured by Kogyo Co., Ltd. was dissolved in 40 parts of MEK, mixed and then dried at 2.6 kPa and 150 ° C. for about 1 hour to remove the solvent, whereby the resin composition (C-2 ) The weight average molecular weight of the resin composition (C-2) was 132,000, and the number average molecular weight was 51,000.

(2-8) Comparative Example 4: Preparation of Resin Composition (A-4) In Example 1, 3 parts of an esterified product of maleic anhydride adduct of polyisoprene and 2-hydroxyethyl methacrylate, and 26. A polymerization reaction and a cyclization reaction were performed in the same manner as in Example 1 except that 7 parts and 0.3 part of MMA were used. The reaction rate of MMA calculated from the amount of residual monomers in the polymerization reaction solution was 18%, and the reaction rate of MHMA was 12%. The composition ratio (mass basis) of the (meth) acrylic polymer chain and the (meth) acrylic polymer bonded to the polyisoprene chain calculated from the reaction rate is MMA: MHMA = 99.3: 0.7. The content ratio of units derived from (meth) acrylic acid ester was 98.9% by mass, and the content ratio of ring structural units was 1.0% by mass. A part of the reaction solution was taken out and subjected to a filtration test. As a result, filtration could be suitably performed. Next, in the same manner as in Example 1, the obtained reaction solution was filtered, reprecipitated, and dried, so that the lactone ring-containing (meth) acrylic polymer and the graft copolymer in which the polymer chain was grafted to the polyisoprene chain. A resin composition (A-4) containing was obtained. The resin composition (A-4) had a weight average molecular weight of 122,000, a number average molecular weight of 31,000, and a chloroform-insoluble content of 2%.

(2-9) Comparative Example 5: Preparation of Resin Composition (B-3) Polymerization reaction and cyclization were performed in the same manner as in Comparative Example 2, except that 49 parts of MMA and 1 part of MHMA were used. Reaction was performed. The reaction rate of MMA calculated from the amount of residual monomers in the polymerization reaction solution was 81%, and the reaction rate of MHMA was 89%. The composition ratio (mass basis) of the lactone ring-containing (meth) acrylic polymer calculated from the reaction rate is MMA: MHMA = 97.8: 2.2, and the content ratio of units derived from (meth) acrylic acid ester is The content of the ring structural unit was 96.5% by mass and 3.2% by mass. Next, in the same manner as in Comparative Example 2, the obtained reaction solution was filtered, re-precipitated, and dried to obtain a resin composition (B-3) containing a lactone ring-containing (meth) acrylic polymer. The resin composition (B-3) had a weight average molecular weight of 145,000 and a number average molecular weight of 63,000.

(2-10) Comparative Example 6: Preparation of Resin Composition (C-3) 1 part of the resin composition (A-4) obtained in Comparative Example 4 and the resin composition (B-3) obtained in Comparative Example 5 9 parts was dissolved in 40 parts of MEK and mixed, and then dried at 2.6 kPa and 150 ° C. for about 1 hour to remove the solvent, thereby obtaining a resin composition (C-3). The weight average molecular weight of the resin composition (C-3) was 144,000, and the number average molecular weight was 60,000.

(2-11) Comparative Example 7: Preparation of Resin Composition (A-5) In Example 1, 3 parts of esterified product of maleic anhydride adduct of polyisoprene and 2-hydroxyethyl methacrylate and 13 parts of MMA The polymerization reaction and the cyclization reaction were performed in the same manner as in Example 1 except that 13 parts of MHMA was used and 0.03 part of stearyl phosphate was used as the cyclization catalyst. The reaction rate of MMA calculated from the amount of residual monomers in the polymerization reaction solution was 19%, and the reaction rate of MHMA was 13%. The composition ratio (mass basis) of the (meth) acrylic polymer chain and (meth) acrylic polymer bonded to polyisoprene calculated from the reaction rate is MMA: MHMA = 59.4: 40.6, The content ratio of units derived from (meth) acrylic acid ester was 27.4% by mass, and the content ratio of ring structural units was 67.1% by mass. When a part of the reaction solution was taken out and a filtration test was conducted, the pressure of the filter was increased. Next, in the same manner as in Example 1, the obtained reaction solution was filtered, reprecipitated, and dried, so that the lactone ring-containing (meth) acrylic polymer and the graft copolymer in which the polymer chain was grafted to polyisoprene, A resin composition (A-5) containing was obtained. The resin composition (A-5) had a weight average molecular weight of 181,000, a number average molecular weight of 32,000, and a chloroform-insoluble content of 11%.

(2-12) Comparative Example 8: Preparation of Resin Composition (B-4) Polymerization reaction and cyclization were performed in the same manner as in Comparative Example 2, except that 25 parts of MMA and 25 parts of MHMA were used. Reaction was performed. The reaction rate of MMA calculated from the amount of residual monomers in the polymerization reaction solution was 87%, and the reaction rate of MHMA was 85%. The composition ratio (mass basis) of the lactone ring-containing (meth) acrylic polymer calculated from the reaction rate is MMA: MHMA = 50.6: 49.4, and the content ratio of units derived from (meth) acrylic acid ester is The content of 9.2% by mass and the ring structural unit was 83.9% by mass. Subsequently, in the same manner as in Comparative Example 2, the obtained reaction solution was filtered, re-precipitated, and dried to obtain a resin composition (B-4) containing a lactone ring-containing (meth) acrylic polymer. The weight average molecular weight of the resin composition (B-4) was 189,000, and the number average molecular weight was 52,000.

(2-13) Comparative Example 9: Preparation of Resin Composition (C-4) 1 part of the resin composition (A-5) obtained in Comparative Example 7 and the resin composition (B-4) obtained in Comparative Example 8 9 parts was dissolved in 40 parts of MEK and mixed, and then dried at 2.6 kPa and 150 ° C. for about 1 hour to remove the solvent, thereby obtaining a resin composition (C-4). The weight average molecular weight of the resin composition (C-4) was 178,000 and the number average molecular weight was 50,000.

(2-14) Example 5: Preparation of resin composition (D-1) A reactor equipped with a stirrer, a temperature sensor, a cooling pipe, and a nitrogen introduction pipe was charged with a SEBS triblock copolymer (manufactured by Kraton, A1536). , Olefinic double bond content 0.10 mmol / g, styrene unit content 39% by mass, refractive index 1.519) 5 parts, methyl methacrylate (MMA) 73 parts, phenylmaleimide (PMI) 18 parts, n-dodecyl Mercaptan (nDM) 0.05 part and 100 parts of toluene as a polymerization solvent were charged, and the temperature was raised to 105 ° C. through nitrogen. Thereafter, 0.009 part of t-butyl peroxyisopropyl carbonate (Kayakaku Akzo Co., Ltd., Kaya-Carbon (registered trademark) Bic75) was added as an initiator, and diluted with 5 parts of styrene (St) and 1 part of toluene. Solution polymerization was carried out at 105 to 110 ° C. while adding 018 parts of t-butylperoxyisopropyl carbonate dropwise at a constant rate over 3 hours, and further aging was carried out for 4 hours. As a result, a resin composition containing a maleimide ring-containing (meth) acrylic polymer formed by polymerization from MMA, PMI, and St and a graft copolymer in which the polymer chain was bonded to a SEBS triblock polymer chain was obtained. . The reaction rate of MMA calculated from the amount of residual monomers in the polymerization reaction solution was 95%, the reaction rate of PMI was 98%, and the reaction rate of St was 100%. The composition ratio (mass basis) of the (meth) acrylic polymer chain and the (meth) acrylic polymer bonded to the SEBS triblock polymer chain calculated from the reaction rate is MMA: PMI: St = 75.9: 18. .9: 5.2, the content ratio of units derived from (meth) acrylic acid ester was 75.9% by mass, and the content ratio of ring structural units was 18.9% by mass. A part of the reaction solution was taken out and subjected to a filtration test. As a result, filtration could be suitably performed.
Next, the obtained polymerization reaction solution was 600 g / h in terms of resin in a vent type screw twin screw extruder (hole diameter: 15 mm, L / D: 45) having one rear vent and two forevents. A resin containing a maleimide ring-containing (meth) acrylic polymer and a graft copolymer in which the polymer chain is bound to a SEBS triblock polymer chain by introducing at a processing speed, performing devolatilization in the extruder, and extruding. A transparent pellet of the composition (D-1) was obtained. The operating conditions of the twin screw extruder were a barrel temperature of 260 ° C., a rotation speed of 300 rpm, and a degree of vacuum of 13.3 to 400 hPa (10 to 300 mmHg). The weight average molecular weight of the resin composition (D-1) is 15 million, the number average molecular weight is 60000, the glass transition temperature on the high temperature side is 138 ° C., the glass transition temperature on the low temperature side is −68 ° C., and chloroform is insoluble. The minute was 0.3% and the refractive index was 1.517. The in-plane retardation Re and the thickness direction retardation Rth of the stretched film of the resin composition (D-1) were 0.9 nm and 2.9 nm, respectively.

(2-15) Example 6: Preparation of Resin Composition (D-2) In Example 5, SEBS triblock copolymer (manufactured by Kraton, A1536) was used as the monomer component charged into the reactor first. The polymerization reaction was carried out in the same manner as in Example 5 except that 10 parts, 69 parts of MMA, and 17 parts of PMI were used. The reaction rate of MMA calculated from the amount of residual monomers in the polymerization reaction solution was 96%, the reaction rate of PMI was 99%, and the reaction rate of St was 100%. The composition ratio (mass basis) of the acrylic polymer chain bonded to the SEBS triblock copolymer chain and the (meth) acrylic polymer calculated from the reaction rate is MMA: PMI: St = 75.2: 19. The content ratio of units derived from (meth) acrylic acid ester was 75.2% by mass, and the content ratio of ring structural units was 19.1% by mass. A part of the reaction solution was taken out and subjected to a filtration test. As a result, filtration could be suitably performed. The resulting polymerization reaction liquid was devolatilized in an extruder in the same manner as in Example 6 to obtain transparent resin composition (D-2) pellets. The weight average molecular weight of the resin composition (D-2) is 148,000, the number average molecular weight is 59,000, the glass transition temperature on the high temperature side is 138 ° C., the glass transition temperature on the low temperature side is −68 ° C., and chloroform is insoluble. The minute was 0.3% and the refractive index was 1.517. The island size of the sea-island structure of the unstretched film of the resin composition (D-2) was 200 nm, and the in-plane retardation Re and the thickness direction retardation Rth of the stretched film were 0.2 nm and 3.5 nm, respectively.

(2-16) Example 7: Preparation of Resin Composition (D-3) In Example 5, SEBS triblock copolymer (manufactured by Kraton, A1536) was used as the monomer component charged into the reactor first. A polymerization reaction was carried out in the same manner as in Example 5 except that 15 parts, 65 parts of MMA and 16 parts of PMI were used and 4 parts of St was used as a monomer component to be added dropwise. The reaction rate of MMA calculated from the amount of residual monomers in the polymerization reaction solution was 96%, the reaction rate of PMI was 99%, and the reaction rate of St was 100%. The composition ratio (mass basis) of the (meth) acrylic polymer chain and the (meth) acrylic polymer bonded to the SEBS triblock polymer chain calculated from the reaction rate is MMA: PMI: St = 75.9: 19. 3: 4.9, the content ratio of units derived from (meth) acrylic acid ester was 75.9% by mass, and the content ratio of ring structural units was 19.3% by mass. A part of the reaction solution was taken out and subjected to a filtration test. As a result, filtration could be suitably performed. The resulting polymerization reaction liquid was devolatilized in an extruder in the same manner as in Example 5 to obtain a transparent resin composition (D-3) pellet. The resin composition (D-3) has a weight average molecular weight of 14,000,000, a number average molecular weight of 53,000, a glass transition temperature on the high temperature side of 137 ° C., a glass transition temperature on the low temperature side of −68 ° C., and chloroform insoluble. The minute was 0.3% and the refractive index was 1.517. The island size of the sea-island structure of the unstretched film of the resin composition (D-3) was 200 nm, and the in-plane retardation Re and the thickness direction retardation Rth of the stretched film were 0.8 nm and 4.5 nm, respectively.

(2-17) Example 8: Preparation of resin composition (D-4) In Example 5, SEBS triblock copolymer (manufactured by Kraton, A1536) was used as the monomer component charged into the reactor first. A polymerization reaction was carried out in the same manner as in Example 5 except that 20 parts, 61 parts of MMA and 15 parts of PMI were used, and 4 parts of St was used as a monomer component to be added dropwise. The reaction rate of MMA calculated from the amount of residual monomers in the polymerization reaction solution was 97%, the reaction rate of PMI was 99%, and the reaction rate of St was 100%. The composition ratio (mass basis) of the (meth) acrylic polymer chain and the (meth) acrylic polymer bonded to the SEBS triblock polymer chain calculated from the reaction rate is MMA: PMI: St = 76.1: 18 .8: 5.1, the content ratio of units derived from (meth) acrylic acid ester was 76.1% by mass, and the content ratio of ring structural units was 18.8% by mass. A part of the reaction solution was taken out and subjected to a filtration test. As a result, filtration could be suitably performed. The resulting polymerization reaction liquid was devolatilized in an extruder in the same manner as in Example 5 to obtain transparent resin composition (D-4) pellets. The resin composition (D-4) has a weight average molecular weight of 145,000, a number average molecular weight of 60,000, a glass transition temperature on the high temperature side of 136 ° C., a glass transition temperature on the low temperature side of −68 ° C., and chloroform insoluble. The minute was 0.4% and the refractive index was 1.517. The island size of the sea-island structure of the unstretched film of the resin composition (D-4) was 250 nm, and the in-plane retardation Re and the thickness direction retardation Rth of the stretched film were 0.5 nm and 6.2 nm, respectively.

(2-18) Example 9: Preparation of Resin Composition (D-5) In Example 5, SEBS triblock copolymer (manufactured by Aldrich, product number 200557) was used as the monomer component initially charged in the reactor. , 10 parts of olefinic double bond content 0.10 mmol / g, styrene unit content 26 mass%, refractive index 1.513), 72 parts MMA, 16 parts PMI The polymerization reaction was performed in the same manner as in Example 5 except that 2 parts of St was used. The reaction rate of MMA calculated from the amount of residual monomers in the polymerization reaction solution was 96%, the reaction rate of PMI was 99%, and the reaction rate of St was 100%. The composition ratio (mass basis) of the (meth) acrylic polymer chain and the (meth) acrylic polymer bonded to the SEBS triblock polymer chain calculated from the reaction rate is MMA: PMI: St = 79.4: 18. .3: 2.3, the content ratio of units derived from (meth) acrylic acid ester was 79.4 mass%, and the content ratio of ring structural units was 18.3 mass%. A part of the reaction solution was taken out and subjected to a filtration test. As a result, filtration could be suitably performed. The obtained polymerization reaction liquid was devolatilized in an extruder in the same manner as in Example 5 to obtain transparent resin composition (D-5) pellets. The resin composition (D-5) has a weight average molecular weight of 172,000, a number average molecular weight of 71,000, a glass transition temperature of 138 ° C., a chloroform insoluble content of 0.4%, and a refractive index of 1.515. there were. The island size of the sea-island structure of the unstretched film of the resin composition (D-5) was 250 nm, and the in-plane retardation Re and the thickness direction retardation Rth of the stretched film were 0.5 nm and 4.9 nm, respectively.

(2-19) Example 10: Preparation of Resin Composition (D-6) In Example 5, SEBS triblock copolymer (manufactured by Asahi Kasei Co., Ltd., Tuftec (registered trademark)) was used as the monomer component initially charged in the reactor. (Trademark) H1041, olefinic double bond content 0.44 mmol / g, styrene unit content 30% by mass, refractive index 1.515) 10 parts, MMA 70 parts, PMI 16 parts A polymerization reaction was performed in the same manner as in Example 5 except that 4 parts of St was used as the body component. The reaction rate of MMA calculated from the amount of residual monomers in the polymerization reaction solution was 97%, the reaction rate of PMI was 99%, and the reaction rate of St was 100%. The composition ratio (mass basis) of the (meth) acrylic polymer chain and the (meth) acrylic polymer bonded to the SEBS triblock polymer chain calculated from the reaction rate is MMA: PMI: St = 77.4: 18. 1: 4.6, the content ratio of units derived from (meth) acrylic acid ester was 77.4% by mass, and the content ratio of ring structural units was 18.1% by mass. A part of the reaction solution was taken out and subjected to a filtration test. As a result, filtration could be suitably performed. The obtained polymerization reaction liquid was devolatilized in an extruder in the same manner as in Example 5 to obtain transparent resin composition (D-6) pellets. The resin composition (D-6) has a weight average molecular weight of 135,000, a number average molecular weight of 56,000, a glass transition temperature of 138 ° C., a chloroform insoluble content of 0.5%, and a refractive index of 1.516. there were. The island size of the sea-island structure of the unstretched film of the resin composition (D-6) was 300 nm, and the in-plane retardation Re and the thickness direction retardation Rth of the stretched film were 0.3 nm and 2.3 nm, respectively.

(2-20) Example 11: Preparation of Resin Composition (D-7) In Example 5, SEBS triblock copolymer (manufactured by Asahi Kasei Co., Ltd., Tuftec (registered trademark)) was used as the monomer component initially charged in the reactor. Trademark) P1083, olefinic double bond amount 2.40 mmol / g, styrene unit content 20% by mass, refractive index 1.500) 10 parts, MMA 83 parts, PMI 6 parts A polymerization reaction was performed in the same manner as in Example 5 except that 1 part of St was used as the body component. The reaction rate of MMA calculated from the amount of residual monomers in the polymerization reaction solution was 96%, the reaction rate of PMI was 99%, and the reaction rate of St was 100%. The composition ratio (mass basis) of the (meth) acrylic polymer chain and the (meth) acrylic polymer bonded to the SEBS triblock polymer chain calculated from the reaction rate is MMA: PMI: St = 92.6: 6. .3: 1.1, the content ratio of units derived from (meth) acrylic acid ester was 92.6% by mass, and the content ratio of ring structural units was 6.3% by mass. A part of the reaction solution was taken out and subjected to a filtration test. As a result, filtration could be suitably performed. The obtained polymerization reaction liquid was devolatilized in an extruder in the same manner as in Example 5 to obtain transparent resin composition (D-7) pellets. The resin composition (D-7) has a weight average molecular weight of 163,000, a number average molecular weight of 62,000, a glass transition temperature of 123 ° C., a chloroform insoluble content of 0.9%, and a refractive index of 1.500. there were. The in-plane retardation Re and the thickness direction retardation Rth of the stretched film of the resin composition (D-7) were 0.3 nm and 4.5 nm, respectively.

(2-21) Example 12: Preparation of Resin Composition (D-8) In Example 5, SEBS triblock copolymer (manufactured by Asahi Kasei Co., Ltd., Tuftec (registered trademark)) was used as the monomer component initially charged in the reactor. Trademark) H1517, Olefinic double bond content 0.11 mmol / g, Styrene unit content 43 mass%, Refractive index 1.525) 10 parts, MMA 63 parts, PMI 24 parts A polymerization reaction was performed in the same manner as in Example 5 except that 3 parts of St was used as the body component. The reaction rate of MMA calculated from the amount of residual monomers in the polymerization reaction solution was 95%, the reaction rate of PMI was 98%, and the reaction rate of St was 100%. The composition ratio (mass basis) of the (meth) acrylic polymer chain and the (meth) acrylic polymer bonded to the SEBS triblock polymer chain calculated from the reaction rate is MMA: PMI: St = 69.3: 27. 2: 3.5, the content ratio of units derived from (meth) acrylic acid ester was 69.3% by mass, and the content ratio of ring structural units was 27.2% by mass. A part of the reaction solution was taken out and subjected to a filtration test. As a result, filtration could be suitably performed. The resulting polymerization reaction solution was devolatilized in an extruder in the same manner as in Example 5 to obtain transparent resin composition (D-8) pellets. The resin composition (D-8) has a weight average molecular weight of 166,000, a number average molecular weight of 63,000, a glass transition temperature of 151 ° C., a chloroform insoluble content of 0.5%, and a refractive index of 1.525. there were. The in-plane retardation Re and the thickness direction retardation Rth of the stretched film of the resin composition (D-8) were 0.5 nm and 5.9 nm, respectively.

(2-22) Comparative Example 10: Preparation of Resin Composition (D-9) In Example 5, SEBS triblock copolymer (manufactured by JSR, Dynanar (registered) was used as the monomer component charged into the reactor first. Trademark) 9901P, olefinic double bond content 0.06 mmol / g, styrene unit content 50 mass%, refractive index 1.530) 10 parts, MMA 30 parts, PMI 55 parts A polymerization reaction was performed in the same manner as in Example 5 except that 5 parts of St was used as the body component. The reaction rate of MMA calculated from the amount of residual monomers in the polymerization reaction solution was 98%, the reaction rate of PMI was 98%, and the reaction rate of St was 100%. The composition ratio (mass basis) of the (meth) acrylic polymer chain and the (meth) acrylic polymer bonded to the SEBS triblock polymer chain calculated from the reaction rate is MMA: PMI: St = 33.3: 61. 0.0: 5.7, the content ratio of units derived from (meth) acrylic acid ester was 33.3 mass%, and the content ratio of ring structural units was 61.0 mass%. A part of the reaction solution was taken out and subjected to a filtration test. As a result, filtration could be suitably performed. The obtained polymerization reaction liquid was devolatilized in an extruder in the same manner as in Example 5 to obtain transparent resin composition (D-9) pellets. The resin composition (D-9) has a weight average molecular weight of 149,000, a number average molecular weight of 59,000, a glass transition temperature of 201 ° C., a chloroform insoluble content of 2.1%, and a refractive index of 1.560. there were. Note that. Although an attempt was made to stretch an unstretched film of the resin composition (D-9), the strength was insufficient and stretching was not possible.

(2-23) Comparative Example 11: Preparation of Resin Composition (D-10) In Example 5, SEBS triblock copolymer (manufactured by Asahi Kasei Co., Ltd., H1052, olefin was used as the monomer component initially charged in the reactor. Monomer component to be added dropwise using 10 parts of styrene double bond content of 0.27 mmol / g, styrene unit content of 20% by mass, refractive index of 1.500), 88.5 parts of MMA and 1.5 parts of PMI. The polymerization reaction was carried out in the same manner as in Example 5 except that St was not used. The reaction rate of MMA calculated from the amount of residual monomers in the polymerization reaction solution was 98%, and the reaction rate of PMI was 98%. The composition ratio (mass basis) of the (meth) acrylic polymer chain and the (meth) acrylic polymer bonded to the SEBS triblock polymer chain calculated from the reaction rate is MMA: PMI = 98.3: 1.7. The content ratio of the unit derived from (meth) acrylic acid ester was 98.3% by mass, and the content ratio of the ring structural unit was 1.7% by mass. A part of the reaction solution was taken out and subjected to a filtration test. As a result, filtration could be suitably performed. The resulting polymerization reaction solution was devolatilized in an extruder in the same manner as in Example 5 to obtain transparent resin composition (D-10) pellets. The resin composition (D-10) has a weight average molecular weight of 145,000, a number average molecular weight of 60,000, a glass transition temperature of 112 ° C., a chloroform insoluble content of 0.4%, and a refractive index of 1.500. there were.

(2-24) Example 13: Preparation of resin composition (D-11) A reactor equipped with a stirrer, a temperature sensor, a cooling pipe, and a nitrogen introduction pipe was charged with a SEBS triblock copolymer (manufactured by Asahi Kasei Corporation, H1052). , Olefinic double bond content 0.27 mmol / g, styrene unit content 20% by mass, refractive index 1.500) 10 parts, methyl methacrylate (MMA) 75 parts, 2- (hydroxymethyl) methyl acrylate (MHMA) ) 13.5 parts, 0.05 part of n-dodecyl mercaptan (nDM), and 100 parts of toluene as a polymerization solvent were charged, and the temperature was raised to 105 ° C. while introducing nitrogen. Thereafter, 0.009 parts of t-butylperoxyisopropyl carbonate (Kayakaku (registered trademark) Bic75, manufactured by Kayaku Akzo Co., Ltd.) was added as an initiator, and the mixture was diluted with 2 parts of styrene (St) and 1 part of toluene. While 015 parts of t-butylperoxyisopropyl carbonate was added dropwise at a constant rate over 2 hours, solution polymerization was carried out at 105 to 110 ° C., followed by further aging for 4 hours. To this was added 0.07 part of stearyl phosphate as a cyclization catalyst, and a cyclization reaction was carried out at 90 to 110 ° C. under reflux for 2 hours. As a result, a resin composition containing a lactone ring-containing (meth) acrylic polymer formed by polymerization from MMA, MHMA, and St and a graft copolymer in which the polymer chain was bonded to a SEBS triblock polymer chain was obtained. . The reaction rate of MMA calculated from the amount of residual monomers in the polymerization reaction solution was 94%, the reaction rate of MHMA was 94%, and the reaction rate of St was 99%. The composition ratio (mass basis) of the (meth) acrylic polymer chain and the (meth) acrylic polymer bonded to the SEBS triblock copolymer chain calculated from the reaction rate is MMA: MHMA: St = 82.6. : 14.9: 2.5, the content ratio of units derived from (meth) acrylic acid ester is 72.9 mass%, the content ratio of ring structural units is 22.8 mass%, the content ratio of units derived from styrene Was 2.4% by mass. A part of the reaction solution was taken out and subjected to a filtration test. As a result, filtration could be suitably performed.
Next, the obtained polymerization reaction liquid was put into an autoclave and subjected to heat treatment at 240 ° C. for 1 hour, and then a vent type screw twin screw extruder (hole diameter: 15 mm, with a rear vent number of 1 and a forevent number of 2). L / D: 45) is introduced into the resin at a processing rate of 600 g / h, devolatilized in this extruder, and extruded to make the lactone ring-containing (meth) acrylic polymer and the polymer chain SEBS. Transparent pellets of a resin composition (D-11) containing a graft copolymer bonded to a triblock polymer chain were obtained. The operating conditions of the twin screw extruder were a barrel temperature of 260 ° C., a rotation speed of 300 rpm, and a degree of vacuum of 13.3 to 400 hPa (10 to 300 mmHg). The resin composition (D-11) has a weight average molecular weight of 155,000, a number average molecular weight of 59,000, a glass transition temperature on the high temperature side of 127 ° C., a glass transition temperature on the low temperature side of −54 ° C., and chloroform insoluble. The minute was 0.4% and the refractive index was 1.500. The island size of the sea-island structure of the unstretched film of the resin composition (D-11) was 250 nm, and the in-plane retardation Re and the thickness direction retardation Rth of the stretched film were 0.3 nm and 4.9 nm, respectively.

(2-25) Example 14: Preparation of resin composition (D-12) In Example 13, SEBS triblock copolymer (manufactured by Kuraray Co., Ltd., Hibler (registered trademark)) was used as the monomer component charged into the reactor first. Trademark) 7125, olefinic double bond content 0.44 mmol / g, styrene unit content 20 mass%) 10 parts, MMA 75 parts, MHMA 13.5 parts Polymerization reaction and cyclization reaction were performed. The reaction rate of MMA calculated from the amount of residual monomers in the polymerization reaction solution was 94%, the reaction rate of MHMA was 94%, and the reaction rate of St was 100%. The composition ratio (mass basis) between the (meth) acrylic polymer chain and the (meth) acrylic polymer bonded to the SEBS triblock polymer chain calculated from the reaction rate is MMA: MHMA: St = 82.7: 14. 8: 2.5, the content ratio of units derived from (meth) acrylic acid ester is 73.0 mass%, the content ratio of ring structural units is 22.7 mass%, and the content ratio of units derived from styrene is 2 It was 4% by mass. A part of the reaction solution was taken out and subjected to a filtration test. As a result, filtration could be suitably performed. The resulting polymerization reaction solution was autoclaved in the same manner as in Example 13, and then devolatilized in an extruder to obtain a transparent resin composition (D-12) pellet. The resin composition (D-12) has a weight average molecular weight of 162,000, a number average molecular weight of 61,000, a glass transition temperature of 127 ° C., a chloroform insoluble content of 0.4%, and a refractive index of 1.500. there were. The island size of the sea-island structure of the unstretched film of the resin composition (D-12) was 250 nm, and the in-plane retardation Re and the thickness direction retardation Rth of the stretched film were 0.2 nm and 4.5 nm, respectively.

(2-26) Example 15: Preparation of Resin Composition (D-13) In Example 13, SEBS triblock copolymer (manufactured by Asahi Kasei Co., Ltd. Trademark) P1083, olefinic double bond content 2.01 mmol / g, styrene unit content 20 mass%) 6 parts, SEBS triblock copolymer 2 (Asahi Kasei Co., Ltd., Tuftec (registered trademark) H1052, olefinic two 4 parts of styrene unit content 20% by mass, refractive index 1.500), 75 parts of MMA, 13.5 parts of MHMA, St is added as a monomer component to be added dropwise. A polymerization reaction and a cyclization reaction were carried out in the same manner as in Example 13 except that 4 parts were used. The reaction rate of MMA calculated from the amount of residual monomers in the polymerization reaction solution was 94%, the reaction rate of MHMA was 94%, and the reaction rate of St was 100%. The composition ratio (mass basis) of the (meth) acrylic polymer chain and the (meth) acrylic polymer bonded to the SEBS triblock polymer chain calculated from the reaction rate is MMA: MHMA: St = 82.6: 14. .9: 2.5, the content ratio of units derived from (meth) acrylic acid ester is 72.6 mass%, the content ratio of ring structural units is 23.0 mass%, and the content ratio of units derived from styrene is 2 It was 4% by mass. A part of the reaction solution was taken out and subjected to a filtration test. As a result, filtration could be suitably performed. The resulting polymerization reaction liquid was autoclaved in the same manner as in Example 13, and then devolatilized in an extruder to obtain transparent resin composition (D-13) pellets. The resin composition (D-13) has a weight average molecular weight of 151,000, a number average molecular weight of 57,000, a glass transition temperature on the high temperature side of 127 ° C., a glass transition temperature on the low temperature side of −61 ° C., and chloroform insoluble. The minute was 0.4% and the refractive index was 1.500. The island size of the sea-island structure of the unstretched film of the resin composition (D-13) was 150 nm, and the in-plane retardation Re and the thickness direction retardation Rth of the stretched film were 0.3 nm and 3.5 nm, respectively.

(2-27) Comparative Example 12: Preparation of Resin Composition (D-14) In Example 13, as a monomer component initially charged in the reactor, SEBS triblock copolymer (Taftec (registered by Asahi Kasei Corporation) was registered. (Trademark) 10 parts of H1041, olefinic double bond amount of 0.45 mmol / g, styrene unit content of 30% by mass), 40 parts of MMA, 45 parts of MHMA. A polymerization reaction was carried out in the same manner as in Example 13 except for using a part. The reaction rate of MMA calculated from the amount of residual monomers in the polymerization reaction solution was 94%, the reaction rate of MHMA was 90%, and the reaction rate of St was 100%. The composition ratio (mass basis) of the (meth) acrylic polymer chain and the (meth) acrylic polymer bonded to the SEBS triblock polymer chain calculated from the reaction rate is MMA: MHMA: St = 45.2: 48. 0.7: 6.0, the content ratio of units derived from (meth) acrylic acid ester is 3.7 mass%, the content ratio of ring structural units is 82.6 mass%, and the content ratio of units derived from styrene is 6 It was 9 mass%. A part of the reaction solution was taken out and subjected to a filtration test. The obtained resin composition (D-14) had a glass transition temperature of 158 ° C. and a chloroform-insoluble content of 10.4%.

Tables 1 to 3 summarize the results of each example and comparative example. The resin composition A-3 of Comparative Example 1 in which no ring structure was introduced into the graft chain had a low glass transition temperature and low heat resistance. Further, even if a ring structure is introduced, the resin composition B-1 of Comparative Example 2, the resin composition B-2 of Comparative Example 3, and the resin composition B-3 of Comparative Example 5 that do not contain a graft copolymer The resin composition B-4 of Comparative Example 8 had a low impact strength (breaking energy) and was inferior in mechanical strength. Resin Composition A-4 of Comparative Example 4, Resin Composition C-3 of Comparative Example 6, Resin Composition A-5 of Comparative Example 7, Resin Composition C-4 of Comparative Example 9, Resin Composition of Comparative Example 10 Product D-9, Resin Composition D-10 of Comparative Example 11 and Resin Composition D-14 of Comparative Example 12 have a (meth) acrylate unit in the graft chain, although the graft chain has a cyclic structural unit. Since the content ratio was less than 45% by mass or more than 98% by mass, the glass transition temperature was low and the heat resistance was poor, the impact strength (fracture energy) was low, the mechanical strength was poor, or a gelled product was generated during production. However, it contains a lot of foreign matter. On the other hand, each of the resin compositions of Examples 1 to 15 was excellent in transparency, mechanical strength, and heat resistance, was provided with a good balance, and generated less gelled products.

According to the present invention, since a copolymer and a resin composition excellent in transparency, mechanical strength, and heat resistance can be obtained, by applying these to an optical film or the like, an excellent polarizer protective film, A polarizing plate, an image display apparatus, etc. can be manufactured.

Claims

Copolymer having polymer chain (A) having units derived from diene and / or olefin, polymer chain (B) having units derived from (meth) acrylic monomers and units having a ring structure in the main chain Because
In the polymer chain (B), a content ratio of the unit derived from the (meth) acrylic acid ester is 45% by mass or more and 98% by mass or less.
The copolymer according to claim 1, wherein the polymer chain (B) is grafted to the polymer chain (A).
The copolymer according to claim 1 or 2, wherein the ring structure is a lactone ring structure and / or a maleimide structure.
The total content of the unit derived from the (meth) acrylic monomer and the unit having a ring structure in the main chain in the polymer chain (B) is 90% by mass or more. The copolymer described.
A resin composition comprising the copolymer according to any one of claims 1 to 4 and a (meth) acrylic polymer.
The resin composition according to claim 5, wherein the (meth) acrylic polymer has units derived from the (meth) acrylic monomer.
The resin composition according to claim 5 or 6, wherein the (meth) acrylic polymer has a unit having a ring structure in the main chain.
The resin composition according to any one of claims 5 to 7, which has a glass transition temperature at 100 ° C or higher and lower than 100 ° C, respectively.
The resin composition according to any one of claims 5 to 8, wherein an insoluble content in chloroform is 10% by mass or less.
An optical film comprising the copolymer according to any one of claims 1 to 4 or the resin composition according to any one of claims 5 to 9.
A polarizing plate comprising the optical film according to claim 10.
An image display device comprising the optical film according to claim 10.
A method for producing the copolymer according to any one of claims 1 to 4,
In the presence of the polymer (P1) having units derived from diene and / or olefin, a monomer component containing a (meth) acrylic monomer and a monomer having a polymerizable double bond in the ring structure is polymerized. A process for producing a copolymer, comprising the step of:
A method for producing the copolymer according to any one of claims 1 to 4,
Polymerizing a monomer component containing a (meth) acrylic monomer in the presence of the polymer (P1) having a unit derived from a diene and / or an olefin;
And a step of forming a ring structure in the main chain of the polymer chain having a unit derived from the (meth) acrylic monomer formed in the polymerization step.
The method for producing a copolymer according to claim 13, further comprising a step of filtering the resin solution obtained in the polymerization step.
The method for producing a copolymer according to claim 14, further comprising a step of filtering the resin solution obtained in the ring structure forming step.