WO2016002865A1

WO2016002865A1 - Two-part mixing-type adhesive agent

Info

Publication number: WO2016002865A1
Application number: PCT/JP2015/069079
Authority: WO
Inventors: 正樹森次; 匡彦太田; 清水　学
Original assignee: 株式会社イーテック
Priority date: 2014-07-03
Filing date: 2015-07-01
Publication date: 2016-01-07
Also published as: JP2017149789A

Abstract

The present invention is a two-part mixing-type adhesive agent comprising a first composition and a second composition, said adhesive agent being characterized in that the first composition contains a complex having both a group derived from an organoborane and a protecting group for the aforementioned group, the second composition contains a compound capable of carrying out a deprotection reaction with the protecting group, and a deprotection reaction product produced by the deprotection reaction between the protecting group and the compound has polymerizability. It is preferred that the protecting group in the complex is derived from a compound having at least two functional groups. The compound from which the protecting group is derived is preferably a diamine.

Description

Two-component mixed adhesive

The present invention relates to a two-component mixed adhesive.

In order to deal with recent environmental problems, there is a demand for weight reduction of automobiles and the like, and therefore resin materials are being used. For this resin material, it is necessary to use an adhesive for joining the resin materials or joining different materials such as metals. However, among resin materials, polypropylene and the like, which are excellent in terms of recycling and cost, are materials that are difficult to bond with an adhesive.

In recent years, an adhesive using an organoborane complex has been studied as a material capable of adhering such a difficult-to-adhere material (see Japanese Patent Publication No. 11-512123 and International Publication No. 2012/160452). In this adhesive, one composition contains a group derived from an organoborane and a complex having the protecting group, and the other composition contains a compound that acts on the protecting group to liberate the organoborane. It is. According to this adhesive, by mixing the two compositions at the time of bonding, the organoborane having radical polymerization initiating ability is liberated, and the adhesive component can be cured and bonded. In this case, radicals generated from the liberated organoborane and oxygen molecules can modify the surface of difficult-to-adhere materials such as polypropylene, so that excellent adhesion can be achieved without plasma treatment or the like. Has been.

However, with the above conventional adhesives, the adhesive strength, the curing rate, and the hot strength showing the adhesiveness at high temperature are still insufficient for the market demand, and the dripping at the time of adhesion cannot be suppressed. There is also an inconvenience.

Japanese National Patent Publication No. 11-512123 International Publication No. 2012/160452

The present invention has been made based on the circumstances as described above, and an object thereof is to provide a two-component mixed adhesive that is excellent in adhesive strength, curing rate, hot strength, and dripping suppression.

The invention made to solve the above problems comprises a first composition (hereinafter also referred to as “composition (I)”) and a second composition (hereinafter also referred to as “composition (II)”). A two-component mixed adhesive, wherein the composition (I) contains a complex having a group derived from an organoborane and a protecting group thereof (hereinafter also referred to as “[A] complex”), and the composition (II) Contains a compound that undergoes a deprotection reaction with the protecting group (hereinafter also referred to as “[D] compound”), and the deprotection reaction product produced by the deprotection reaction between the protecting group and the [D] compound has a polymerizable property. It is characterized by having.

The two-component mixed adhesive includes the composition (I) containing the [A] complex and the composition (II) containing the [D] compound, so that the adhesive strength, the curing rate, the hot strength, Excellent sag control. The reason why the two-component mixed adhesive has the above-described configuration and thus achieves the above effect is not necessarily clear, but can be inferred as follows, for example. That is, when the protecting group of the [A] complex and the [D] compound undergo a deprotection reaction, the released organoborane and the polymerization site in the deprotection reaction product are located closer to each other, resulting in more effective polymerization. It is considered that the curing rate is improved. In addition to the improvement in the curing rate, the adhesive layer formed by polymerization contains a group generated by the deprotection reaction, so that the strength is further improved and the interaction with the adherend is increased. It is considered that the hot strength is improved. Furthermore, it is considered that thixotropy is increased and liquid dripping suppression is improved due to the fact that moderate interaction is exerted between groups generated by the deprotection reaction.

[A] The protecting group of the complex is preferably derived from a compound having two or more functional groups. Thus, the deprotection reaction product formed from the protective group of [A] complex and the [D] compound by making the compound derived from the protective group of [A] complex have two or more functional groups. As a result of the product having a plurality of polymerization sites, the curing rate is further improved, and since the resulting polymer has a three-dimensional cross-linked structure, the adhesive strength and the hot strength can be further improved. Furthermore, it is thought that the interaction between groups produced by the above-mentioned deprotection reaction increases, and the dripping suppression property is further improved.

Diamine is preferable as the compound derived from the protecting group. Thus, by using the diamine as the compound derived from the protective group of the [A] complex, the speed of the deprotection reaction is increased and the curing rate is further improved, and the group formed by the deprotection reaction exhibits a hydrogen bond. As a result, it is considered that the strength of the adhesive layer and the interaction with the adherend can be further increased, and the adhesive strength and the hot strength are further improved. Moreover, since a hydrogen bond can be appropriately formed between groups generated by the deprotection reaction, the dripping suppression property can be further improved.

The [D] compound is preferably a (meth) acrylate having an isocyanate group. Thus, by using the specific compound as the [D] compound, the deprotection reaction rate and the polymerization rate are further increased, the curing rate is further improved, and the groups formed by the deprotection reaction are increased. As a result of further increasing the interaction, the adhesive strength, the hot strength, and the dripping suppression property can be further improved.

The molar ratio of the isocyanate group to the diamine is preferably 1 or more and 3 or less. Thus, by making the said molar ratio into the said specific range, adhesive strength, a cure rate, hot strength, and dripping suppression property can further be improved.

It is preferable that the composition (I), the composition (II) or both further contain a (meth) acrylate or polymer component having no isocyanate group. Thus, since the composition (I) and / or the composition (II) contains a (meth) acrylate or polymer component having no isocyanate group, the two-component mixed adhesive has the strength of the adhesive layer. Further, the adhesive strength and the hot strength are further improved, and the initial adhesive strength can be improved and the curing shrinkage can be suppressed.

The (meth) acrylate having no isocyanate group preferably has an alicyclic ring. As described above, the (meth) acrylate having no isocyanate group has an alicyclic ring, whereby the two-component mixed adhesive can further improve the hot strength.

It is preferable that polymer particles are contained as the polymer component. Thus, by containing polymer particles as the polymer component, the two-component mixed adhesive can further improve the flexibility of the adhesive layer.

The content of the polymer particles in the polymer component is preferably 10% by mass or more and 50% by mass or less. Thus, by making the content rate of the polymer particles in the specific range, the two-component mixed adhesive can increase both the flexibility and the adhesive strength of the adhesive layer.

The polymer particles preferably have a core-shell structure. As described above, since the polymer particles have a core-shell structure, the two-component mixed adhesive can further improve the flexibility of the adhesive layer. The “core-shell structure” refers to a structure having a core part serving as a nucleus and a shell part covering the core part. However, it is not necessary that the core part is entirely covered with the shell part.

The molar ratio of the protecting group to the group derived from organoborane in the complex is preferably 1 or more and 8 or less. Thus, the storage stability of the two-component mixed adhesive can be improved by setting the molar ratio of the protecting group to the group derived from the organoborane within the specific range.

The thixotropy index is preferably 3 or more. The said 2 liquid mixture type adhesive can exhibit high dripping suppression property by making the value of TI into the said range. The “thixotropic index (TI)” refers to the ratio of the viscosity (η ₅ ) measured at ₅ rpm to the viscosity (η ₅₀ ) measured at 50 rpm.

As described above, according to the two-component mixed adhesive of the present invention, high adhesive strength and hot strength can be obtained at a high curing rate while suppressing dripping. Therefore, the two-component mixed adhesive can be suitably used for bonding various materials including difficult-to-adhere materials such as automobile outer plates.

It is a measurement chart of the temperature dependence of storage elastic modulus (E ') and loss tangent (tan delta) about the two-component mixed type adhesive of an example and a comparative example.

<Two-component mixed adhesive>
The two-component mixed adhesive includes a composition (I) and a composition (II). The two-component mixed adhesive includes the composition (I) containing the [A] complex and the composition (II) containing the [D] compound, so that the adhesive strength, the curing rate, the hot strength, Excellent sag control.

In the two-component mixed adhesive, the composition (I) and the composition (II) are mixed so that the [D] compound in the composition (II) is converted into the [A] in the composition (I). A reaction (deprotection reaction) occurs with the protecting group constituting the complex, and as a result, a reaction product of organoborane and the protecting group with the [D] compound (hereinafter also referred to as “deprotection reaction product (p)”). ) Is generated. This deprotection reaction product (p) has polymerizability, for example, it is polymerized using the produced organoborane as a polymerization initiator, and in addition, for example, a radical formed from the organoborane and the adherend. Bonding or the like is also formed, and adhesion proceeds.

The two-component mixed adhesive can exhibit the above effects without requiring the inclusion of a curing accelerator such as an acid halide compound. The reason why the two-component mixed adhesive has the above-described configuration provides the above-mentioned effect is not necessarily clear, but can be inferred as follows, for example. That is, when the protective group of the [A] complex and the [D] compound undergo a deprotection reaction, the liberated organoborane and the polymerization site in the deprotection reaction product become closer to each other, resulting in more effective polymerization. It is believed that the cure rate is improved. In addition to the improvement in the curing rate, the adhesive layer formed by polymerization contains a group generated by the above deprotection reaction, so that the strength is further improved and the interaction with the adherend is increased, so the adhesive strength is improved. In addition, it is considered that the hot strength is improved. Furthermore, it is considered that thixotropy is increased and liquid dripping suppression is improved due to the fact that moderate interaction is exerted between groups generated by the deprotection reaction. In addition, according to the two-component mixed adhesive, the deprotection reaction product (p) is bonded to the adhesive layer by polymerization and taken in by adopting the above configuration, so that the bleed out from the adhesive layer is prevented. It is thought to be reduced.

In addition to the composition (I) and the composition (II), the two-component mixed adhesive further includes another composition that does not contain the [A] complex and the [D] compound, and is a mixture of three or more components. A mold adhesive may be used.

Hereinafter, the composition (I) and the composition (II) will be described.

<Composition (I)>
Composition (I) contains a [A] complex. The composition (I) preferably contains a compound having one polymerizable group (hereinafter also referred to as “[B] polymerizable compound”) and / or a [C] polymer component. In the range not impairing the above, other components other than the above-mentioned components [A] to [C] may be contained. Hereinafter, each component will be described.

[[A] complex]
[A] The complex is a complex having a group derived from organoborane and a protecting group thereof. [A] The complex is usually formed from an organoborane and a compound (a) capable of forming a protective group by coordination bonding to the organoborane and suppressing the polymerization initiation ability of the organoborane. Organoborane can form an [A] complex by interacting with one or more compounds (a).

(Organoborane)
The organoborane is a compound in which the hydrogen atom of borane is substituted with an organic group. An organic group refers to a group containing at least one carbon atom. Examples of the organoborane include compounds represented by the following formula (1).

In the above formula (1), R ¹ , R ² and R ³ are monovalent organic groups having 1 to 20 carbon atoms.

Examples of the monovalent organic group having 1 to 20 carbon atoms represented by R ¹ , R ² and R ³ include, for example, a monovalent hydrocarbon group having 1 to 20 carbon atoms, and the carbon-carbon gap of the hydrocarbon group. And a group (α) having a divalent heteroatom-containing group, a group in which part or all of the hydrogen atoms of the hydrocarbon group and the group (α) are substituted with a monovalent heteroatom-containing group, and the like.

Examples of the monovalent hydrocarbon group having 1 to 20 carbon atoms include, for example, a monovalent chain hydrocarbon group having 1 to 20 carbon atoms, a monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms, Examples thereof include 6-20 monovalent aromatic hydrocarbon groups.

Examples of the monovalent chain hydrocarbon group having 1 to 20 carbon atoms include alkyl groups such as a methyl group, an ethyl group, a propyl group, and a butyl group;
An alkenyl group such as an ethenyl group, a propenyl group, a butenyl group;
Examples thereof include alkynyl groups such as ethynyl group, propynyl group and butynyl group.

Examples of the monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms include cycloalkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, norbornyl group, adamantyl group, and tricyclodecyl group;
And cycloalkenyl groups such as a cyclopentenyl group, a cyclohexenyl group, a norbornenyl group, and a tricyclodecenyl group.

Examples of the monovalent aromatic hydrocarbon group having 6 to 20 carbon atoms include aryl groups such as phenyl group, tolyl group, xylyl group, naphthyl group, and anthryl group;
Examples thereof include aralkyl groups such as benzyl group, phenethyl group, and naphthylmethyl group.

Examples of the hetero atom contained in the monovalent and divalent heteroatom-containing group include an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, and a silicon atom.

Examples of the divalent heteroatom-containing group include —O—, —CO—, —NR′—, —S—, —CS—, —SO—, —SO ₂ —, —POR ′ ₂ —, and —SiR. ' _2- , a group combining these and the like. R ′ is a monovalent hydrocarbon group having 1 to 10 carbon atoms.

Examples of the monovalent heteroatom-containing group include —OH, —COOH, —NH ₂ , —CN, —NO ₂ , —SH and the like.

The organoborane is preferably a compound in which R ¹ to R ^{3 in} the above formula (1) are hydrocarbon groups from the viewpoint of high polymerization initiating ability, stability, and availability, more preferably trialkylborane, Borane, triethylborane, tripropylborane and tributylborane are more preferred, and triethylborane is particularly preferred.

(Compound (a))
Compound (a) is a compound that serves as a protective group for organoborane and can undergo a deprotection reaction with the [D] compound described below.

Examples of the compound (a) include compounds having a functional group (hereinafter also referred to as “functional group (x)”). The functional group (x) is preferably a functional group containing a hetero atom from the viewpoint of both the ability to form a complex with an organoborane and the ease of deprotection reaction with the [D] compound. As said hetero atom, a nitrogen atom, an oxygen atom, a sulfur atom, a phosphorus atom etc. are mentioned, for example. The hetero atom is preferably an atom having an unshared electron pair from the viewpoint of further enhancing the ability to form a complex with an organoborane and the ease of the deprotection reaction with the [D] compound.

As the functional group containing the hetero atom,
Examples of the functional group containing a nitrogen atom include an amino group, a substituted amino group (a hydrogen atom of —NH ₂ substituted with a hydrocarbon group), an imino group (—CH═N—), and the like.
Examples of the functional group containing an oxygen atom include a hydroxy group and an ether group.
Examples of the functional group containing a sulfur atom include a sulfanyl group and a thioether group.
Examples of the functional group containing a phosphorus atom include a phosphino group, a substituted phosphino group (a hydrogen atom of —PH ₂ substituted with a hydrocarbon group), and the like.

Examples of compounds having an amino group include monoamines such as methylamine, ethylamine, propylamine, butylamine, aniline, and ethanolamine;
1,2-diaminoethane, 1,2-diaminopropane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1 , 8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,12-diaminododecane, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenyl ether, 4,4′-diaminobenzophenone, 2,2-bis (4-aminophenyl) propane, 2- (3-aminophenyl) -2- (4-aminophenyl) propane, 1,4-bis [1- (4-aminophenyl) -1-methyl Ethyl] benzene, 1,3-bis [1- (4-aminophenyl) -1-methylethyl] benzene, 4,7,10-trioxatrideca 1,13-diamine, 4,9-oxa-1,12-diamine, diamines such as 3,6,9-trio key sound-1,11-diamine;
And triamines such as 1,2,3-triaminopropane, 1,2,4-triaminobutane, 1,3,5-triaminocyclohexane, 1,3,5-triaminobenzene, and the like.

Examples of the compound having a substituted amino group include dimethylamine, diethylamine, dipropylamine, dibutylamine, cyclopentylamine, cyclohexylamine, dicyclopentylamine, dicyclohexylamine, N, N′-dimethyl-1,3-diaminopropane, N , N, N ′, N′-tetramethyl-1,3-diaminopropane, diethanolamine and the like.

Examples of the compound having an imino group include N-methylbutylaldimine.

Examples of the compound having a hydroxy group include monoalcohols such as methanol and ethanol;
Diols such as ethylene glycol, 1,4-butanediol, 1,2-cyclohexanediol;
Examples include triols such as glycerin and trimethylolpropane.

Examples of the compound having an ether group include diethyl ether, dibutyl ether, tetrahydrofuran and the like.

Examples of the compound having a sulfanyl group include monothiols such as mercaptan and ethanethiol;
And dithiols such as ethanedithiol and butanedithiol.

Examples of the compound having a thioether group include diethyl thioether, dibutyl thioether, tetrahydrothiophene and the like.

Examples of the compound having a phosphino group include monophosphines such as ethylphosphine and butylphosphine;
Examples include diphosphinoethane and diphosphinobutane.

Examples of the compound having a substituted phosphino group include diethyl phosphine and dibutyl phosphine.

The number of functional groups (x) possessed by the compound (a) may be 1 or 2 or more, preferably 2 or more, more preferably 2 to 4 and even more preferably 2 or 3 Two are particularly preferred. By setting the number of functional groups (x) within the above range, a deprotection reaction product having a plurality of polymerization sites (A) and a protective group of the [A] complex formed from the compound (a) and a compound [D] ( As a result of the formation of p), the curing rate is further improved, and the resulting polymer has a three-dimensional crosslinked structure, so that the adhesive strength and the hot strength can be further improved. Moreover, it is thought that the interaction between groups which arises by the above-mentioned deprotection reaction increases, and dripping suppression property improves more.

As the functional group (x), those having a hetero atom to which at least one hydrogen atom is bonded are preferred from the viewpoint of facilitating the deprotection reaction between the protective group and the [D] compound. Examples of such a functional group (x) include an amino group, —NHR, hydroxy group, sulfanyl group, phosphino group, —PHR and the like. R is a monovalent hydrocarbon group. Among these, from the viewpoint of further facilitating the deprotection reaction, an amino group and —NHR are preferable, and an amino group is more preferable.

The compound (a) is preferably an active hydrogen-containing compound having a hetero atom to which at least one hydrogen atom is bonded, from the viewpoint of facilitating the deprotection reaction between the protecting group and the [D] compound. Among these, the compound (a) is preferably a compound containing an amino group, more preferably a diamine and a triamine, from the viewpoint of further facilitating the deprotection reaction and further increasing the adhesive strength and hot strength. More preferred are diamines having diaminoalkanes and ether bonds, particularly preferred are diaminoalkanes having 2 to 4 carbon atoms and diamines having ether bonds having 6 to 12 carbon atoms, and 1,3-aminopropane and 4,7 , 10-trioxatridecane-1,13-diamine is most preferred.

The lower limit of the molar ratio of the group derived from the compound (a) in the [A] complex to the group derived from the organoborane is preferably 0.5, more preferably 0.7, still more preferably 0.9, Is particularly preferred, 1.8 is more particularly preferred, 2.5 is even more particularly preferred, and 3.5 is most preferred. The upper limit of the molar ratio is preferably 8, more preferably 7, still more preferably 6, and particularly preferably 5.5. By making the said molar ratio into the said range, the stability of a [A] complex can be improved more and, as a result, the storage stability of the said 2 liquid mixture type adhesive can be improved more.

The lower limit of the molar ratio of the compound (a) to the organoborane used in the preparation of the composition (I) is preferably 0.5, more preferably 0.7, still more preferably 0.9, and particularly preferably 1. 1.8 is more particularly preferable, 2.5 is further particularly preferable, and 3.5 is most preferable. The upper limit of the molar ratio is preferably 8, more preferably 7, still more preferably 6, and particularly preferably 5.5. By making the said molar ratio into the said range, the stability of a [A] complex can be improved more and, as a result, the storage stability of the said 2 liquid mixture type adhesive can be improved more.

The lower limit of the content of the [A] complex in the composition (I) is 0.1 mass from the viewpoint of further improving the adhesive strength, curing rate, hot strength, and sag suppression of the two-component mixed adhesive. % Is preferable, 0.5% by mass is more preferable, 1% by mass is further preferable, and 2% by mass is particularly preferable. The upper limit of the content is preferably 20% by mass, more preferably 10% by mass, further preferably 6% by mass, and particularly preferably 4% by mass from the viewpoint of easy handling of the two-component mixed adhesive.

[[B] polymerizable compound]
[B] The polymerizable compound is a compound having one polymerizable group (provided that the compounds corresponding to the [C] polymer component and the [D] compound are excluded). By including the [B] polymerizable compound, the two-component mixed adhesive can improve the strength of the adhesive layer, and as a result, the adhesive strength and the hot strength can be further improved.

Examples of the polymerizable group include carbon-carbon double bond-containing groups such as a vinyl group, allyl group, styryl group, and (meth) acryloyl group; carbon-carbon triple bond-containing groups such as ethynyl group and propargyl group. .
Among these, a carbon-carbon double bond-containing group is preferable and a (meth) acrylolyl group is more preferable from the viewpoint of superior polymerizability.

[B] Examples of the polymerizable compound include olefins such as butene, pentene, hexene, octene, decene, and dodecene;
Styrene compounds such as styrene, α-methylstyrene and methylstyrene;
Vinyl carboxylates such as vinyl acetate, vinyl propionate and vinyl laurate;
Halogenated olefins such as vinyl chloride and vinylidene chloride;
Vinyl compounds such as methyl vinyl ketone and methyl vinyl ether;
Alkyl (meth) acrylates such as methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate;
Cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, 4-butylcyclohexyl (meth) acrylate, bornyl (meth) acrylate, isobornyl (meth) acrylate, tricyclodecan-yl (meth) acrylate, tetracyclododecan-yl (meth) ) Having an alicyclic ring such as cycloalkenyl (meth) acrylate such as cycloalkyl (meth) acrylate such as acrylate, cyclopentenyl (meth) acrylate, cyclohexenyl (meth) acrylate, tricyclodecenyl (meth) acrylate (meta) ) Acrylate;
Aryl (meth) acrylates such as phenyl (meth) acrylate and tolyl (meth) acrylate;
Heteroatom-containing (meth) acrylates such as hydroxyethyl (meth) acrylate, glycidyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate;
(Meth) acrylamide, N-methyl (meth) acrylamide, (meth) acrylonitrile and the like can be mentioned.

Of these, (meth) acrylate is preferred from the viewpoint of superior polymerizability, and (meth) acrylate having no isocyanate group is more preferred. Among them, from the viewpoint of reducing the odor of the two-component mixed adhesive and from the viewpoint of dissolving the [C] polymer component described later, a heteroatom-containing (meth) acrylate is preferable, and tetrahydrofurfuryl (meth) acrylate is more preferable. . From the viewpoint of imparting flexibility to the adhesive layer, alkyl (meth) acrylate is preferable, and 2-ethylhexyl (meth) acrylate is more preferable. From the viewpoint of further improving the hot strength, (meth) acrylate having an alicyclic ring is preferable, cycloalkyl (meth) acrylate is more preferable, and tricyclodecyl (meth) acrylate is further preferable. [B] One or two or more polymerizable compounds may be used.

When the composition (I) contains a [B] polymerizable compound, the lower limit of the content of the [B] polymerizable compound in the composition (I) is preferably 10% by mass, more preferably 30% by mass, 50 mass% is further more preferable, and 60 mass% is especially preferable. As an upper limit of the said content, 99 mass% is preferable, 95 mass% is more preferable, 90 mass% is further more preferable, 85 mass% is especially preferable. By setting the content to be between the lower limit and the upper limit, the strength of the adhesive layer can be further improved, and as a result, the adhesive strength and the hot strength can be further improved.

[[C] Polymer component]
The composition (I) preferably contains a [C] polymer component from the viewpoint of improving the initial adhesive strength and adjusting the viscosity of the two-component mixed adhesive, and suppressing the curing shrinkage of the adhesive layer.

[C] The polymer component is not particularly limited as long as it is a polymer, and examples thereof include polyolefin, polystyrene, styrene copolymer, poly (meth) acrylate, polydiene, acrylic copolymer, and thermoplastic elastomer. Further, ethylene-vinyl acetate copolymer, epoxy resin, phenol resin, silicone resin, polyester resin, urethane resin, and the like can be used. Furthermore, as a [C] polymer component, the copolymer containing the structure of these polymers can also be used suitably.

Examples of the polyolefin include polyethylene, polypropylene, and ethylene-α-olefin copolymers.

Examples of the polystyrene include polystyrene and poly (α-methylstyrene).

Examples of the styrene copolymer include styrene-methyl methacrylate copolymer, styrene-acrylic acid copolymer, styrene-maleic anhydride copolymer, styrene-acrylonitrile copolymer, ABS (acrylonitrile-butadiene-styrene copolymer). Polymer) and the like.
Examples of the poly (meth) acrylate include polymethyl (meth) acrylate, polyethyl (meth) acrylate, polybutyl (meth) acrylate and the like.

Examples of the polydiene include polybutadiene and polyisoprene.

Examples of the acrylic copolymer include polymers having plural types of (meth) acrylic acid ester units, butyl (meth) acrylate-acrylonitrile copolymers, and the like.
Examples of the thermoplastic elastomer include SBS (styrene-butadiene-styrene block copolymer), SEBS (styrene-ethylene-butadiene-styrene block copolymer), SIS (styrene-isoprene-styrene block copolymer), and SEPS. Non-hydrogenated products of conjugated diene copolymers such as (styrene-ethylene-propylene-styrene block copolymer), and hydrogenated products thereof.

Among these, from the viewpoint of having a more appropriate viscosity, thermoplastic elastomers and poly (meth) acrylates are preferable, and thermoplastic elastomers are more preferable.

[C] The polymer component preferably has a polymerization site. [C] Since the polymer component has a polymerization site, the [C] polymer component and the deprotection reaction product (p), etc. are copolymerized. As a result, the above-mentioned improvement in initial adhesive strength, viscosity adjustment and cure shrinkage Suppression can be performed more effectively. Examples of the polymerization site include a carbon-carbon double bond in the polymer main chain, a polymerizable group in the side chain or terminal of the polymer, and the like. Examples of the [C] polymer component having a polymerization site include an unhydrogenated product of a conjugated diene copolymer. Among these, SBS is preferable from the viewpoint of having a more appropriate viscosity.

[C] The polymer component may be a polymer particle or a polymer that does not form a particle. The composition (I) preferably contains polymer particles as the [C] polymer component. When the composition (I) contains polymer particles, the two-component mixed adhesive can further improve the flexibility of the adhesive layer. The composition (I) more preferably contains polymer particles and a polymer not forming particles as the [C] polymer component. When the composition (I) contains both the polymer particles and the polymer not forming the particles, the two-component mixed adhesive can further improve the flexibility of the adhesive layer.

[C] The polymer component forming the polymer particles is preferably a polyolefin, polystyrene, styrene copolymer, poly (meth) acrylate, polydiene acrylic copolymer, or a copolymer containing the structure of these polymers, and polystyrene. , Poly (meth) acrylates, polydienes and copolymers comprising the structures of these polymers are more preferred.

The lower limit of the average particle diameter of the polymer particles is preferably 0.005 μm, more preferably 0.01 μm, further preferably 0.05 μm, and particularly preferably 0.1 μm. The upper limit of the average particle diameter is preferably 1 μm, more preferably 0.8 μm, further preferably 0.6 μm, and particularly preferably 0.4 μm.

Examples of the polymer particles include single particles and particles having a core-shell structure (core-shell particles). Of these, core-shell particles are preferred. By using core-shell particles as the polymer particles, the two-component mixed adhesive can further improve the flexibility of the adhesive layer. Examples of such commercially available core-shell particles include “Kane Ace M-511”, “M-521”, “M-570”, “M-711” of Kaneka Corporation, “FX602P” of JSR Corporation. ”,“ FX501 ”,“ Zeon F351 ”manufactured by Nippon Zeon Co., Ltd., and the like.

[C] When polymer particles are contained as the polymer component, the lower limit of the content of the polymer particles in the [C] polymer component is preferably 10% by mass, more preferably 15% by mass, and 20% by mass. Further preferred is 25% by mass. As an upper limit of the said content rate, 70 mass% is preferable, 50 mass% is more preferable, 45 mass% is further more preferable, 40 mass% is especially preferable. By setting the content of the polymer particles in the above range, the two-component mixed adhesive can increase both the flexibility and the adhesive strength of the adhesive layer.

As the [C] polymer component not forming the particles, styrene copolymer, poly (meth) acrylate, polydiene, thermoplastic elastomer, silicone resin, polyester resin and urethane resin are preferable, and thermoplastic elastomer is more preferable. SBS is more preferred.

When the composition (I) contains a [C] polymer component, the lower limit of the content of the [C] polymer component in the composition (I) is preferably 1% by mass, more preferably 5% by mass, and 8% by mass. % Is more preferable, and 10% by mass is particularly preferable. As an upper limit of the said content, 60 mass% is preferable, 45 mass% is more preferable, 35 mass% is further more preferable, 30 mass% is especially preferable. By setting the content to be between the lower limit and the upper limit, it is possible to effectively improve the initial adhesive strength, adjust the viscosity, suppress the curing shrinkage of the adhesive layer, and the like.

[Other ingredients]
The composition (I) may contain, for example, a crosslinkable compound, a plasticizer, an inorganic filler, a colorant, a polymerization inhibitor and the like as other components other than the above-described components [A] to [C]. These other components may contain 1 type (s) or 2 or more types, respectively.

(Crosslinkable compound)
The crosslinkable compound is a compound having two or more polymerizable groups. By including a crosslinkable compound in the composition (I), the hot strength and the elongation percentage of the adhesive layer can be further increased.

Examples of the polymerizable group possessed by the crosslinkable compound include those exemplified as the polymerizable group possessed by the above-mentioned [B] polymerizable compound. Among these, a (meth) acryloyl group is preferable from the viewpoint that the polymerization rate can be increased and the hot strength can be further increased.

The number of polymerizable groups possessed by the crosslinkable compound is preferably 2 to 4, more preferably 2 or 3, and even more preferably 2 from the viewpoint of improving the hot strength.

Examples of the crosslinkable compounds include chain glycol crosslinkable compounds such as ethylene glycol di (meth) acrylate and triethylene glycol di (meth) acrylate;
Alicyclic glycol-based crosslinkable compounds such as tricyclodecanediyl di (meth) acrylate;
Trimethylolpropane-based crosslinkable compounds such as trimethylolpropane tri (meth) acrylate;
Bisphenol crosslinkable compounds such as bisphenol A bis (polyethylene glycol (meth) acrylate);
Imido isocyanurate crosslinkable compounds such as tri (N-hydroxyethyl) isocyanurate di (meth) acrylate;
Urethane-based crosslinkable compounds such as compounds represented by the following formula (2);
Examples thereof include terminal bismaleimide-modified polyimide crosslinkable compounds such as a compound represented by the following formula (3).

In the above formula (2), m is an integer of 1-20.
In the above formula (3), n is an integer of 1-20. R ⁴ and R ⁵ are each independently an alkylene group having 1 to 20 carbon atoms. Ar ¹ is an arylene group having 6 to 20 carbon atoms. When n is 2 or more, the plurality of R ⁴ may be the same or different, and the plurality of Ar ¹ may be the same or different.

As the crosslinkable compound, an alicyclic glycol-based crosslinkable compound is preferable, and tricyclodecanediyl di (meth) acrylate is more preferable.

When the composition (I) contains a crosslinkable compound, the content of the crosslinkable compound in the composition (I) is 0.1% by mass from the viewpoint of further increasing the hot strength and the elongation rate of the adhesive layer. Preferably, 0.5 mass% is more preferable, and 2 mass% is further more preferable. As an upper limit of the said content, 20 mass% is preferable, 15 mass% is more preferable, 12 mass% is further more preferable, and 10 mass% is especially preferable.

Examples of the plasticizer include phthalic acid esters such as dibutyl phthalate, di (2-ethylhexyl) phthalate and butyl benzyl phthalate; non-aromatic dibasic acid esters such as dioctyl adipate and dioctyl sebacate; dipropylene glycol dibenzoate, tri Examples thereof include benzoic acid esters such as ethylene glycol dibenzoate.

Examples of the inorganic filler include alumina, silica, titanium dioxide and the like.

Examples of the colorant include carbon black.

The metal salt can be contained for adjusting the pot life of the two-component mixed adhesive. Examples of the metal salt include copper (II) bromide, copper (II) chloride, copper (II) 2-ethylhexanoate and the like.

Examples of the polymerization inhibitor include hydroquinone and hydroquinone monomethyl ether.

<Composition (II)>
Composition (II) contains a [D] compound. The composition (II) preferably contains the [B] polymerizable compound ”and / or the [C] polymer component, and may contain other components, like the composition (I). .
Hereinafter, each component will be described.

[[D] Compound]
The compound [D] is a compound that forms a deprotection reaction product (p) by deprotection reaction with the protecting group of the above-mentioned [A] complex, and the deprotection reaction product (p) has polymerizability. . As described above, when the two-component mixed adhesive is used, by mixing the composition (I) and the composition (II), the [D] compound undergoes a deprotection reaction with the protecting group of the [A] complex. As a result, a deprotection reaction product (p) and an organoborane are produced, and the deprotection reaction product (p) is polymerized due to the polymerization initiation ability of the organoborane, whereby the adhesion proceeds.

Examples of the [D] compound include a compound having a group capable of deprotecting with the above protecting group (hereinafter also referred to as “group (a)”) and a polymerizable group.

The group (a) is not particularly limited as long as it can react with the protecting group. For example, a carbonyl group, a thiocarbonyl group, a nitroso group, an imino group (—CH═N—), an isocyanate group, an isothiocyanate group , Groups having a heteroatom-containing multiple bond such as an isocyanide group and a phosphate group;
A cyclic group containing a hetero atom such as an epoxy group or a cyclic carbonate group;
Examples include an acid halide group, an ester group, an amide group, an acid anhydride group, and a leaving group-containing group such as a carboxy group. The group (a) includes a vinyl group corresponding to a polymerizable group described later. Among these, a group having a heteroatom-containing multiple bond is preferable from the viewpoint of easier deprotection reaction and higher curing rate, and higher interaction between groups formed by the deprotection reaction, and adhesion. From the viewpoint of further increasing the strength, hot strength, and dripping suppression, an isocyanate group and an isothiocyanate group are more preferable, and an isocyanate group is further preferable.

As said polymeric group, the group similar to what was illustrated as a polymeric group which the said [B] polymeric compound has, for example is mentioned.
Among these, a (meth) acryloyl group is preferable from the viewpoints of high polymerizability and a higher curing rate.

The number of groups (a) possessed by the [D] compound is preferably 1 to 3, more preferably 1 and 2, and even more preferably 1 from the viewpoint of facilitating the deprotection reaction.

[D] The number of polymerizable groups possessed by the compound is preferably 1 to 3, more preferably 1 and 2, more preferably 1 from the viewpoint of further increasing the polymerization rate of the deprotection reaction product (p) to be formed. preferable.

[D] As the combination of the number of groups (a) and the number of polymerizable groups in the compound, the number of groups (a) is preferably 1 and 2, and the number of polymerizable groups is preferably 1 and 2, and the group (a) And the number of polymerizable groups is preferably 1.

As the compound [D], for example, as a compound having an isocyanate group,
Isocyanatoalkyl (meth) acrylates such as isocyanatoethyl (meth) acrylate and isocyanatopropyl (meth) acrylate; (meth) acrylates having an isocyanate group such as an adduct of diisocyanate and hydroxyalkyl (meth) acrylate;
Examples thereof include alkenes having an isocyanate group such as isocyanatobutene, isocyanatopentene, and isocyanatohexene.

In addition, as a compound having an isothiocyanate group,
Isothiocyanatoalkyl (meth) acrylates such as isothiocyanatoethyl (meth) acrylate and isothiocyanatopropyl (meth) acrylate; having an isothiocyanate group such as an adduct of diisothiocyanate and hydroxyalkyl (meth) acrylate ( (Meth) acrylate;
Examples include alkene having an isothiocyanate group such as isothiocyanatobutene, isothiocyanatopentene, isothiocyanatohexene and the like.

Among these, (meth) acrylate having an isocyanate group and (meth) acrylate having an isothiocyanate group are preferable, (meth) acrylate having an isocyanate group is more preferable, isocyanatoalkyl (meth) acrylate is further preferable, and isocyanate. Natoethyl (meth) acrylate is particularly preferred.

The lower limit of the content of the [D] compound in the composition (II) is preferably 0.2% by mass, more preferably 1% by mass, further preferably 2% by mass, and particularly preferably 2.5% by mass. As an upper limit of the said content, 40 mass% is preferable, 20 mass% is more preferable, 10 mass% is further more preferable, 7 mass% is especially preferable. By setting the content of the [D] compound between the lower limit and the upper limit, the adhesive strength and the curing rate of the two-component mixed adhesive can be further increased.

[D] As a combination of the group (a) in the compound and the functional group (x) of the compound (a) in the [A] complex, the group (a) is an isocyanate group or an isothiocyanate group, and the group (x) is It is preferably an amino group, more preferably the group (a) is an isocyanate group and the group (x) is an amino group. When the group (a) and the functional group (x) are combined as described above, a urea group is generated by the deprotection reaction, and as a result, the thixotropic property of the two-component mixed adhesive is further increased. This is presumably because, for example, an appropriate hydrogen bond works between the urea groups of the deprotection reaction product (p).

The lower limit of the molar ratio of the group (a) to the protecting group is preferably 0.5, more preferably 0.7, still more preferably 1, and particularly preferably 1.5. The upper limit of the molar ratio is preferably 6, more preferably 4, more preferably 3, and particularly preferably 2.5. By setting the molar ratio between the lower limit and the upper limit, it is possible to further increase the adhesion rate, the curing rate, the hot strength, and the dripping suppression property of the two-component mixed adhesive.

When the group (a) is an isocyanate group and the protective group-derived compound is a diamine, the lower limit of the molar ratio of the isocyanate group to the diamine is preferably 1, more preferably 1.3, and even more preferably 1.5 1.7 is particularly preferable. The upper limit of the molar ratio is preferably 3, more preferably 2.7, even more preferably 2.5, and particularly preferably 2.3. By setting the molar ratio between the lower limit and the upper limit, it is possible to further increase the adhesion rate, the curing rate, the hot strength, and the dripping suppression property of the two-component mixed adhesive.

The lower limit of the thixotropy index (TI) of the two-component mixed adhesive is preferably 3 as a value immediately after mixing the composition (I) and the composition (II), more preferably 5, and further 6 preferable. The upper limit of the TI is preferably 10, more preferably 9, and even more preferably 8. The said 2 liquid mixture type adhesive can exhibit high dripping suppression property by making TI value between the said minimum and the said upper limit. In addition, the said TI value can be calculated | required by preparing what does not contain an [A] complex in composition (I), and measuring this and mixing with composition (II).

[[B] polymerizable compound]
The composition (II) preferably contains [B] a polymerizable compound. [B] The explanation about the polymerizable compound, the preferred one and the content thereof are the same as in the case of the composition (I).

[[C] Polymer component]
The composition (II) preferably contains a [C] polymer component. [C] The explanation, preferred and content of the polymer component are the same as in the case of the composition (I).

[Other ingredients]
The composition (II) may contain other components. About description, preferable thing, and content about another component, it is the same as that of the case of composition (I). The crosslinkable compound is preferably contained in the composition (II).

<Method for preparing two-component mixed adhesive>
The two-component mixed adhesive is prepared by, for example, preparing the composition (I) by mixing the [A] complex and, if necessary, the [B] polymerizable compound, the [C] polymer component, and other components, Separately, it can be obtained by preparing the composition (II) by mixing the [D] compound and, if necessary, the [B] polymerizable compound, the [C] polymer component and other components.

<How to use a two-component mixed adhesive>
The two-component mixed adhesive can be used by a known method. For example, during the bonding operation, the composition (I) and the composition (II) are mixed, and after the obtained mixture is applied to one of the adherends, the other adherend is brought into close contact with the applied mixture. Thus, it can be carried out by overlapping. Moreover, after apply | coating the said mixture to both to-be-adhered materials, you may make it closely adhere these applied mixtures. As the adherend, polypropylene (PP), polyethylene (PE), polyphenylene sulfide (PPS), polyamide 6 (PA6), polyamide 66 (PA66) and other resin materials; stainless steel (SUS), hot dip galvanized steel (SGHC) ), Metal materials such as electrodeposited steel (ED), etc., of which the same or different types can be used, and resin materials, metal materials and resin materials-metal materials can be bonded Can do. The thickness of the adhesive layer formed between the two adherends is usually 0.01 mm to 5 mm, preferably 0.05 mm to 3 mm, more preferably 0.1 mm to 1 mm.

Hereinafter, the present invention will be specifically described based on examples, but the present invention is not limited to these examples.

<Preparation of two-component mixed adhesive>
[Example 1] (Preparation of two-component mixed adhesive (J-1))
(Preparation of [B] polymerizable compound and [C] polymer component mixed solution)
A 300 mL separable flask equipped with a stirrer was charged with 20.0 g of SBS and 60.0 g of tetrahydrofurfuryl methacrylate (THFMA), and stirred in an oil bath at 40 ° C. for 3 hours to completely dissolve SBS in THFMA. Next, 17.5 g of 2-ethylhexyl methacrylate (2EHMA) was added, and the mixture was further stirred for 1 hour and mixed, and then degassed under reduced pressure for 2 hours to prepare a mixed solution (a).

(Preparation of composition (I))
97.5 g of the mixed solution (a) prepared above and 2.5 g of triethylborane-diaminopropane complex (TEB-DAP) as a complex [A] were placed in a plastic container and mixed to obtain a composition (I- 1) was prepared.

(Preparation of composition (II))
95.5 g of the prepared mixed solution (a) and 4.5 g of 2-isocyanatoethyl methacrylate (MOI) as the [D] compound were placed in a plastic container and mixed to obtain a composition (II-1) Was prepared.

In addition, the following were used for each component used for preparation.
SBS: “TR2787” from JSR
THFMA: “Light Ester THF” from Kyoeisha Chemical Co., Ltd.
2EHMA: Kyoeisha Chemical Company's “Light Ester EH”
TEB-DAP: “TEB-DAP” from BASF Japan
MOI: “Karenz MOI” from Showa Denko

[Examples 2 to 4] (Preparation of two-component mixed adhesives (J-2) to (J-4))
For the composition (I), the composition (I-1) prepared in Example 1 was directly used as the compositions (I-2) to (I-4). For the composition (II), the mass of MOI used / the mass of the mixed solution (a) used in the preparation of the composition (II-1) of Example 1 was 6.75 g / 93.25 g, 5. Compositions (II-2) to (II-4) were prepared in the same manner as in Example 1, except that the amount was 4 g / 94.6 g, 3.6 g / 96.4 g.

[Comparative Example 1] (Preparation of two-component mixed adhesive (CJ-1))
As for the composition (I), the composition (I-1) prepared in Example 1 was used as it was as the composition (IC).

Composition (II) was prepared as follows. A 300 mL separable flask equipped with a stirrer was charged with 20.0 g of SBS and 54.75 g of THFMA and stirred in an oil bath at 40 ° C. for 3 hours to completely dissolve SBS in THFMA. Next, 15.0 g of 2EHMA, 10.0 g of mono-2- (methacryloyloxy) ethyl maleate and 0.25 g of p-toluenesulfonyl chloride were added, and the mixture was further stirred for 1 hour and then degassed under reduced pressure for 2 hours. A composition (II-C) was obtained.

<Evaluation>
Using each of the two-component mixed adhesives prepared above, a test piece for measuring adhesive strength was prepared according to the following method, and the adhesive strength (shear strength and T-type peel strength) was measured by the following shear test and T-type peel test. ,evaluated. Further, the elongation percentage of the adhesive layer was measured according to the following method.

[Measurement of shear strength]
(Test piece preparation method)
Prepare two adherends (each 2.5 cm long × 10 cm wide) and immediately before applying the adhesive, clean the surface with a paper wiper containing acetone (“Kimwipe” from Nippon Paper Crecia). Removed. Next, the composition (I) and the composition (II) were mixed by a bag mixing method. That is, in a polyethylene bag, the composition (I) and the composition (II) are respectively weighed so as to have a mass ratio of 1: 1, sealed, and mixed uniformly. Mix for 1 minute by rolling. Next, the corners of the bag were cut with scissors, and the mixed adhesive was uniformly applied to one 1.25 cm square portion of the adherend. In order to make the thickness of the adhesive constant, glass beads having a diameter of 0.25 mm were sandwiched, and the other adherend was stacked on top to prepare a test piece.

(Shear test method)
With respect to the prepared test piece, the tensile shear strength of the bonded portion was measured according to JIS-K6850 using a tensile tester (“Autograph AG5000B” manufactured by Shimadzu Corporation). The measurement conditions were as follows: temperature: 23 ° C., distance between chucks: 110 mm, test speed: 5 mm / min.

[Measurement of T-peel strength]
(Test piece preparation method)
Prepare two pieces of adherend processed by bending an adherend (ED steel plate) 2.5 cm long × 20 cm wide at 90 ° at 5 cm from one side, and applying an adhesive to each. Immediately before, surface dirt was removed with a paper wiper containing acetone (“Kimwipe” manufactured by Nippon Paper Crecia Co., Ltd.). Adhesives were mixed in the same manner as in the above-described shear test piece preparation method, and the mixed adhesive was uniformly applied to one long side portion of the adherend. In order to make the thickness of the adhesive constant, glass beads having a diameter of 0.25 mm were sandwiched, and the other adherend was stacked on top to prepare a test piece.

(T-type peel test method)
With respect to the prepared test piece, the T-shaped peel strength of the bonded portion was measured according to JIS-K6854-3 using a tensile tester (“Autograph AG5000B” manufactured by Shimadzu Corporation). The measurement conditions were as follows: temperature: 23 ° C., distance between chucks: 50 mm, test speed: 200 mm / min.

[Measurement of elongation rate of adhesive layer]
(Test piece preparation method)
Adhesive mixing is performed in the same manner as in the above shear test piece preparation method, and the mixed adhesive is sandwiched between PET films on the top and bottom in a 2 mm thick stainless steel mold and cured at room temperature for 4 days. A flat sheet-like cured product was produced. A dumbbell test piece was prepared from the obtained sheet using a dumbbell-shaped No. 2 dumbbell punching machine defined in JISK-6251.

For the dumbbell test piece produced above, the elongation at break of the cured product was measured using a tensile tester (“Autograph AG5000B” manufactured by Shimadzu Corporation). The measurement conditions were as follows: temperature: 23 ° C., distance between chucks: 30 mm, test speed: 100 mm / min. The elongation percentage of the adhesive layer was calculated from the moving distance of the chuck when the test piece broke.

[Adhesive strength and curing speed]
Table 1 (in the case of glass fiber reinforced polypropylene / glass fiber reinforced polypropylene (GFPP / GFPP)) and Table 2 show the relationship between curing time and adhesive strength for the two-component mixed adhesives of Example 1 and Comparative Example 1. (In the case of electrodeposited steel / electrodeposited steel (ED / ED)).

From the results of Tables 1 and 2, it was shown that the two-component mixed adhesives of the examples were superior in both curing speed and adhesive strength as compared with the comparative examples.

[Type of substrate]
The adhesion between various adherends was evaluated. As the adherend, glass fiber reinforced polypropylene (GFPP), polyethylene (PE), polyphenylene sulfide (PPS), polyamide 6 (PA6) and polyamide 66 (PA66) are used as the resin material, and stainless steel (SUS) is used as the metal material. Using the combinations shown in Table 3 below, the adhesive strength was measured using hot dip galvanized steel (SGHC) and electrodeposited steel (ED). The measured values of shear strength are shown in Table 3 below.

Also, the failure mode was visually evaluated. The fracture modes indicate A: interface fracture, B: material fracture, B ′: material stretching, and C: cohesive fracture, respectively. “C> A” indicates that the fracture mode is complex, mainly cohesive fracture, and partially interfacial fracture). The subscripts A and B in the failure mode indicate the material in which the failure occurred.

From the results of Table 3, it is shown that the two-component mixed adhesive of the example can exhibit high adhesive strength to various types of adherends, and the two-component mixed adhesive of the comparative example It was also shown that a high adhesive strength can be obtained even for an adherend having a low adhesive strength in the case of an agent.

[Hot strength]
The hot strength was evaluated by performing a tensile test in a 90 ° C. atmosphere on a test piece cured for 7 days at room temperature (the results of the tensile test performed at room temperature are also shown). As the adherend, two ED plates were used. The evaluation results are shown in Table 4 below. The destruction mode is also shown.

From the results in Table 4, it was shown that according to the two-component mixed adhesive of the example, the heat resistance of the adhesive layer was higher than that of the comparative example, and the strength reduction during heating could be suppressed.

[Dynamic viscoelasticity]
For the two-component mixed adhesive, the dynamic viscoelasticity of the cured product obtained by mixing the two components using a dynamic viscoelasticity measuring apparatus (UBM “Rheogel-E4000”) and curing at room temperature for 4 days was measured. The temperature dependence of the storage elastic modulus (E ′) and loss tangent (tan δ) and the glass transition temperature (Tg) were determined. The measurement chart is shown in FIG. 1 ((A) the two-component mixed adhesive (J-1) of Example 1 and (B) the two-component mixed adhesive (CJ-1) of Comparative Example 1). Tg was 76 ° C. in Example 1 and 68 ° C. in Comparative Example 1.
In the two-component mixed adhesives of Examples, the Tg was higher than that of Comparative Examples, and the storage elastic modulus in the viscous region was high, so that an increase in crosslinking density was observed.

[Molar ratio of isocyanate group to amino group]
The evaluation results of the shear strength and fracture mode of the two-component mixed adhesives prepared in Examples 1 to 4 above are the molar ratios of isocyanate groups / diamines (and NCO groups / NH ₂ groups included in the two-component mixed adhesives). Are shown in Table 5 below together with the value of “-” In Table 5 indicates that no destruction was observed.

From the results in Table 5, it can be seen that setting the molar ratio of the isocyanate group to the diamine to be 1 or more and 3 or less is effective in increasing the adhesive strength.

[Thixotropic index (TI)]
In the preparation of the composition (I) of Example 1 and Comparative Example 1, 1.08 g of 1,3 was added to the mixed solution (a) containing no TEB-DAP complex so as to have the same number of moles as TEB-DAP. Using a composition to which diaminopropane is added (composition (I ′)), the composition (I ′) and each composition (II) (compositions (II-1) and (II-C) are in a mass ratio) The mixed solutions (J′-1) and (CJ′-1) were prepared by mixing 1: 1, and the viscosity of the obtained mixed solution was measured with a viscometer (“RE-85U type viscometer manufactured by Toki Sangyo Co., Ltd.). )), The respective viscosities (η ₅ and η ₅₀ ) were determined at different rotation speeds of 5 rpm and 50 rpm, and the TI values (= η ₅ / η ₅₀ ) were calculated from these measured values. The measured values and calculated TI values are shown in Table 6 below.

From the results in Table 6, it was shown that the two-component mixed adhesives of the examples had higher thixotropic properties than those of the comparative examples. This high thixotropy is obtained by mixing the composition (I) and the composition (II) in the two-component mixed adhesive (J-1) of Example 1 and reacting with the isocyanate group and the amino group. It is considered that a urea group is generated as a group generated by the deprotection reaction, and an appropriate hydrogen bond is formed between the urea groups. Due to this high thixotropy, dripping during use of the two-component mixed adhesive is suppressed.

<Preparation of two-component mixed adhesive>
In Examples 5 to 7 and 11 below, those forming a matrix and particles were used as the [C] polymer component. In Examples 8 to 10, the amount of the [A] complex was examined.

[Example 5] (Preparation of two-component mixed adhesive (J-5))
(Preparation of composition (I))
[A] 2.5 g of TEB-DAP as a complex, 6B of THFMA and 17.5 g of 2EHMA as a [B] polymerizable compound, and 20.0 g of SBS as a [C] polymer component are mixed in a plastic container. To prepare a composition (I-5).

(Preparation of composition (II))
[B] 55.7 g of THFMA and 16.2 g of 2EHMA as polymerizable compounds, 18.6 g of SBS as a polymer component and 5.0 g of “Kaneace M-521” of Kaneka Corporation as core-shell particles, [D] A 4.5 g MOI compound was placed in a plastic container and mixed to prepare a composition (II-5).

[Examples 6 to 11] (Preparation of two-component mixed adhesives (J-6) to (J-11))
A composition (I) and a composition (II) were prepared in the same manner as in Example 5 except that the components of the types and blending amounts shown in Table 7 below were used. “-” In Table 7 indicates that the corresponding component was not used. In addition, Table 7 shows the types and blending amounts of the components in the compositions (I) and (II) of the two-component mixed adhesive prepared in Examples 1 to 4 and Comparative Example 1. “* 1” in Comparative Example 1 indicates that 10.0 g of mono 2- (methacryloyloxy) ethyl maleate and 0.25 g of p-toluenesulfonyl chloride were blended.

Using each of the two-component mixed adhesives prepared above, the shear strength, T-peel strength, and elongation rate of the adhesive layer were measured according to the above methods. The evaluation results are shown in Table 8 below. In Table 8, “−” in Examples 2 to 4 indicates that each physical property was not measured. In addition, “-” in Examples 7 and 11 indicates that it was difficult to prepare the composition. The evaluation results in Examples 1 to 4 and Comparative Example 1 are also shown in Table 8.

From the results of Table 8, according to the two-component mixed adhesives of the examples, [C] the polymer component can be used in combination with the matrix component and the particle component to improve the T-shaped peel strength and the adhesive layer. It was shown that the flexibility of can be increased. Moreover, from the result of Table 8, according to the two-component mixed adhesive of the example, it was also shown that the shear strength and the T-shaped peel strength can be further improved by optimizing the blending amount of the [A] complex. .

In Examples 12 to 16 below, [B] (meth) acrylate having an alicyclic ring as a polymerizable compound and a crosslinkable compound were used.

[Example 12] (Preparation of two-component mixed adhesive (J-12))
(Preparation of composition (I))
[A] 2.5 g of TEB-DAP as a complex, 60.0 g of THFMA as a polymerizable compound and 17.5 g of tricyclodecyl methacrylate (TCDMA: “FA-513M” from Hitachi Chemical Co., Ltd.), [C] A composition (I-12) was prepared by placing 20.0 g of SBS as a polymer component in a plastic container and mixing them.

(Preparation of composition (II))
[B] THFMA 58.0 g and TCDMA 17.5 g as a polymerizable compound, [C] SBS 20.0 g as a polymer component, and MOD 4.5 g as a [D] compound were placed in a plastic container and mixed. Composition (II-12) was prepared.

[Examples 13 to 16]
A composition (I) and a composition (II) were prepared in the same manner as in Example 12 except that the components of the types and blending amounts shown in Table 9 below were used. TCDDMA (tricyclodecane dimethacrylate) as a crosslinkable compound was “Light Ester DCP-M” manufactured by Kyoeisha Chemical Co., Ltd. “-” In Table 9 indicates that the corresponding component was not used.

Using each of the two-component mixed adhesives prepared above, the shear strength at room temperature and the shear strength at 80 ° C. (hot strength) were measured according to the above method. The evaluation results are shown in Table 10 below.

From the results of Table 10, it was shown that according to the two-component mixed adhesive of the example, the shear strength at room temperature can be further improved by using the [B] polymerizable compound having an alicyclic ring. It was also shown that the hot strength can be further improved by using a crosslinkable compound.

In Examples 17 to 19 below, the molar ratio between the group derived from organoborane in the [A] complex and its protecting group was examined.

[Example 17] (Preparation of two-component mixed adhesive (J-17))
(Preparation of composition (I))
[A] A mixture of 2.5 g of TEB-DAP as a complex and 1.0 g of 4,7,10-trioxatridecane-1,13-diamine (TTD), and [B] 53.8 g of THFMA as a polymerizable compound; 15.6 g of 2EHMA, 17.7 g of SBS as a [C] polymer component, and 9.9 g of core-shell particles were placed in a plastic container and mixed to prepare composition (I-17).

(Preparation of composition (II))
[B] THFMA 52.0 g and 2EHMA 15.2 g as a polymerizable compound, [C] SBS 17.3 g and core-shell particles 9.6 g as a polymer component, and [D] MOI 5.9 g as a compound A composition (II-17) was prepared by mixing in a container.

[Examples 18 and 19]
A composition (I) and a composition (II) were prepared in the same manner as in Example 17 except that the components of the types and blending amounts shown in Table 11 below were used. “-” In Table 11 indicates that the corresponding component was not used.

Using each of the two-component mixed adhesives prepared above, the shear strength at room temperature and the T-shaped peel strength were measured according to the above method. The evaluation results are shown in Table 12 below.

From the results of Table 12, it was shown that the shear strength and the T-shaped peel strength can be further improved by optimizing the molar ratio between the group derived from the organoborane in the [A] complex and the protecting group. .

[Storage stability]
The viscosity η ₅₀ (mPa · s) of the composition (I) shown in Table 13 below was measured immediately after preparation (storage time 0 days) and after storage at 40 ° C. for 7 days. The viscosity of the composition was measured at 50 rpm using a viscometer (“TE-85U viscometer” manufactured by Toki Sangyo Co., Ltd.). The viscosity values at each storage time of the composition are shown in Table 13 below together with the molar ratio of the protecting group (amino group) to the group derived from the organoborane in the [A] complex of the composition (I).

From the results shown in Table 13, by increasing the molar ratio of the protecting group to the group derived from the organoborane of the [A] complex, the change in the viscosity of the composition (I) with time is small, gelation is suppressed, and storage is performed. It was shown that the stability can be further improved.

According to the two-component mixed adhesive of the present invention, high adhesive strength and hot strength can be obtained at a high curing rate while suppressing liquid dripping. Therefore, the two-component mixed adhesive can be suitably used for bonding various materials including difficult-to-adhere materials such as automobile outer plates.

Claims

A two-component mixed adhesive comprising a first composition and a second composition,
The first composition contains a complex having a group derived from organoborane and a protecting group thereof,
The two-component mixing characterized in that the second composition contains a compound that undergoes a deprotection reaction with the protecting group, and the deprotection reaction product produced by the deprotection reaction between the protecting group and the compound has polymerizability. Mold adhesive.
The two-component mixed adhesive according to claim 1, wherein the protective group of the complex is derived from a compound having two or more functional groups.
The two-component mixed adhesive according to claim 1 or 2, wherein the protective group-derived compound is a diamine.
The two-component mixed adhesive according to claim 1, 2 or 3, wherein the deprotecting compound is a (meth) acrylate having an isocyanate group.
The compound derived from the protecting group is a diamine,
The two-component mixed adhesive according to claim 4, wherein the molar ratio of the isocyanate group to the diamine is 1 or more and 3 or less.
The two-component mixed adhesive according to any one of claims 1 to 5, wherein the first composition, the second composition, or both further contain a (meth) acrylate or polymer component having no isocyanate group. Agent.
The two-component mixed adhesive according to claim 6, wherein the (meth) acrylate having no isocyanate group has an alicyclic ring.
The two-component mixed adhesive according to claim 6 or 7, which contains polymer particles as the polymer component.
The two-component mixed adhesive according to claim 8, wherein the content of the polymer particles in the polymer component is 10% by mass or more and 50% by mass or less.
The two-component mixed adhesive according to claim 8 or 9, wherein the polymer particles have a core-shell structure.
The two-component mixed adhesive according to any one of claims 1 to 10, wherein the molar ratio of the protecting group to the group derived from organoborane in the complex is 1 or more and 8 or less.
The two-component mixed adhesive according to any one of claims 1 to 11, wherein the thixotropy index is 3 or more.