RU2813974C1 - Adhesive composition - Google Patents

Abstract

FIELD: adhesives.

SUBSTANCE: adhesive composition includes polychloroprene rubber Nairit DP, butylphenol-formaldehyde resin 101 K, water, zinc oxide, magnesium oxide, an organic solvent and a phosphorus-nitrogen-comprising modifier. The organic solvent is a mixture of ethyl acetate and nefras. The product of the interaction of dicyandiamine with dimethylphosphite in a phosphoric acid environment applied to carbon microfibres is used as a phosphorus-nitrogen-comprising modifier. The modifier is applied to carbon microfibres in the form of a 5 wt.% aqueous solution. The mass ratio of carbon microfibres to an aqueous solution of the modifier is 10:1-5.

EFFECT: increased adhesion of the adhesive composition to rubber and the heat resistance of the adhesive joint.

1 cl, 2 tbl

Description

The invention relates to adhesive compositions and can be used in the rubber industry for gluing vulcanized rubbers based on various rubbers to each other.

A known adhesive composition includes polychloroprene rubber Nairit DP, butylphenol formaldehyde resin 101 K, water, zinc oxide, magnesium oxide, an organic solvent, which is a mixture of ethyl acetate and nefras, and a methyl phosphite borate modifier (RF Patent 2393194, IPC C09J111/00; Publ. 06/27/10).

However, this adhesive composition does not provide sufficiently high strength when gluing products made of vulcanized rubber.

Known adhesive compositions include polychloroprene rubber Nairit DP, butylphenol-formaldehyde resin 101 K, water, zinc oxide, magnesium oxide, an organic solvent, which is a mixture of ethyl acetate and nefras, and a modifier consisting of aniline production bottom waste with an aniline content of 15-18 parts by weight. . and glycidyl ester of methacrylic acid (RF Pat. 2263128, IPC C09J111/00, C08L11/00; Published 10/27/05) or epoxy diane resin ED-20 (RF Pat. 2252237, IPC C09J111/00; Published 05/20/05) .

However, these adhesive compositions have insufficient strength when gluing vulcanized rubber to each other.

A known adhesive composition includes polychloroprene rubber, butylphenol-formaldehyde resin, styrene-piperylene copolymer, rosin esterified with glycerol; pine rosin, diphenylguanidine, 2,2-dibenzthiazole disulfide, zinc oxide, magnesium oxide, organic solvent (RF Pat. 2028358, IPC C09J111/00, C09J161/08, C09J125/10, C09J193/04; Publ. 02/09/95).

However, the specified adhesive composition, although it has a similar composition, is intended for gluing products made of ferrites.

The closest to the invention in technical essence is a composition comprising polychloroprene rubber Nairit DP, butylphenol formaldehyde resin 101 K, water, zinc oxide, magnesium oxide, an organic solvent, which is a mixture of ethyl acetate and nefras, a modifier containing epoxy diane resin ED-20, aniline and dimethylphosphite, with a mass ratio of epoxy diane resin ED-20:aniline:dimethylphosphite equal to 1:0.3-0.5:0.2-0.4 (RF Pat. 2677175, C09J111/00; Publ. 2019).

However, this adhesive composition has insufficient strength when gluing vulcanized rubber to each other.

The objective of the present invention is to develop an adhesive composition that has increased strength and heat resistance when gluing vulcanized rubber to each other.

The technical result is an increase in the adhesive properties of the adhesive composition to rubbers based on various rubbers and an increase in the heat resistance of the adhesive joint.

The stated technical result is achieved in an adhesive composition comprising polychloroprene rubber Nairit DP, butylphenol-formaldehyde resin 101 K, water, zinc oxide, magnesium oxide, an organic solvent, which is a mixture of ethyl acetate and nefras, and a phosphorus-nitrogen-containing modifier; the reaction product of dicyandiamine is used as a phosphorus-nitrogen-containing modifier with dimethyl phosphite in an environment of 50 wt.% phosphoric acid, previously applied to carbon microfibers at a mass ratio of carbon microfibers: 5 wt.% aqueous solution of modifier = 10: 1-5, with the following ratio of composition components, wt. h.:

Polychloroprene rubber Nairit DP 90.0

Butylphenol-formaldehyde resin 101 K 90.0

Water 3.0

Zinc oxide 5.0

Magnesium oxide 11.0

Organic solvent 800.0

Carbon microfibers with applied modifier 10.0

When used as a modifier for the reaction product of dicyandiamine with dimethyl phosphite in a phosphoric acid environment - DDF, the adhesive properties of the adhesive composition are significantly increased. As a result of the interaction of DDF (modifier) with the polychloroprene rubber macromolecule, the concentration of polar groups increases and additional chemical bonds are formed, which contributes to an increase in the mobility of the polychloroprene macromolecule and deeper diffusion of its sections deep into the surface of the vulcanizate.

The presence of carbon microfibers in the adhesive composition contributes to additional micro-reinforcement of the adhesive film, which leads to strengthening of the adhesive seam.

Polychloroprene rubber Nairit DP (TU-6-01-131985) is the main film-forming agent in adhesive solutions.

Butylphenol-formaldehyde resin 101 K (TU-6-10-1261-8).

Vulcanizing group: zinc oxide (zinc whitening GOST 202-84), magnesium oxide (burnt magnesia GOST 844-79) were previously used in adhesive compositions (Kardashov D.A., Petrova A.V. Polymer adhesives. - M.: Chemistry, 1983).

Organic solvent: mixture of ethyl acetate (GOST 8981-78) and nefras (GOST 443-76) in a ratio of 1:1.

As a modifying additive, the product of the interaction of dicyandiamine with dimethyl phosphite in an environment of 50 wt.% phosphoric acid, previously applied by thermostatting to carbon microfibers from a 5 wt.% aqueous solution of a modifier (DDP), is used. Thermostating of microfiber is carried out in an aqueous solution of DDF at a mass ratio of carbon microfibers: 5 wt.% aqueous solution of DDF equal to 10: 1-5, at a temperature of 100 ^o C, until it is completely evaporated. After this, carbon microfibers with an applied modifier are dried to a constant weight and introduced into the rubber mixture in an amount of 10 wt. h.

The compositions of the adhesive compositions are given in Table 1.

Table 1

Component Content of components, mass. h., in composition 1 2 3 Test example Prototype Polychloroprene rubber Nairit DP 90 90 90 90 90 Butylphenol formaldehyde resin 101 K 90 90 90 90 90 Water 3 3 3 3 3 Zinc oxide 5 5 5 5 5 Magnesium oxide eleven eleven eleven eleven eleven Organic solvent 800 800 800 800 800 Epoxy diane resin ED-20 - - - - 2.63 Aniline - - - - 1.32 Dimethylphosphite - - - - 1.05 Carbon microfibers with an applied modifier, at a mass ratio of carbon microfibers: 5 wt.% aqueous solution of modifier = 10: 1 10.0 - - Carbon microfibers with an applied modifier, at a mass ratio of carbon microfibers: 5 wt.% aqueous solution of modifier = 10: 3 10.0 - - Carbon microfibers with an applied modifier, at a mass ratio of carbon microfibers: 5 wt.% aqueous solution of modifier = 10: 5 10.0 - -

The adhesive composition is prepared as follows.

A calculated amount of carbon microfibers with an applied modifier is introduced into an adhesive mixer containing Nairite glue 88 SA (TU 381051760-89), prepared in a known manner, including polychloroprene rubber Nairit DP, butylphenol-formaldehyde resin 101K, zinc oxide, magnesium oxide, water and the specified organic solvent. and mix the contents for 5-10 minutes until a homogeneous mass is obtained.

It has been established that the most optimal is to use 5.0-1.0 parts by mass. 5 wt.% aqueous solution of DDF modifier.

The adhesive composition is a beige liquid. It is technologically advanced and applies well to the rubber surface.

Comparative tests of the strength properties of adhesive compositions for all variants of the claimed composition and prototype when gluing vulcanized rubber based on ethylene propylene diene (SKEPT-40), polyisoprene (SKI-3), butadiene-nitrile (SKN-18) and chloroprene rubber (Bypren) (CPC) are given in table 2.

table 2

Shear strength, MPa Indicator for composition 1 2 3 Counter. example Prototype SKN-18 1.31 1.75 1.28 0.83 1.25 COD 2.35 2.10 1.72 1.70 1.36 SKI-3 0.88 1.35 0.9 0.80 - SKEPT-40 0.60 0.70 0.65 0.57 - Evaluation of the heat resistance of the adhesive joint at t=80 ⁰ C* SKEPT-40 0.43 0.48 0.56 0.38 -

*exposure time 4 hours.

The proposed adhesive compositions were tested for adhesive shear strength, achieved when kept under a load of 2 kg, at room temperature (20°C) for 24 hours. Shear adhesion was determined using a RMI-50 tensile testing machine (GOST 16971-71).

The technology for gluing samples is as follows. A one-time application of the prepared glue to the prepared surface, drying the adhesive film at room temperature for 5 minutes, after which the surfaces to be glued were pressed tightly.

When assessing the heat resistance of the adhesive joint, pre-glued samples using the method presented above were subjected to thermal exposure for 4 hours, followed by assessment of the strength of the adhesive joint.

As can be seen from Table 2, the proposed adhesive compositions provide an increase in the strength properties of adhesive joints compared to the prototype. Thus, the shear strength of the adhesive seam when gluing vulcanized rubber based on SKN-18 according to the prototype is 1.25 MPa, and with the use of the proposed modifier it is 1.75 MPa.

Thus, an adhesive composition comprising polychloroprene rubber Nairit DP, butylphenol-formaldehyde resin 101 K, water, zinc oxide, magnesium oxide, an organic solvent, which is a mixture of ethyl acetate and nefras, and a phosphorus-nitrogen-containing modifier - a product of the interaction of dicyandiamine with dimethylphosphite in an environment of 50 wt.% phosphoric acid, previously applied to carbon microfibers at a mass ratio of carbon microfibers: 5 wt.% aqueous solution of modifier = 10: 1-5, at the stated ratio of the components of the composition, provides an increase in the adhesive properties of the adhesive composition to rubbers based on various rubbers.

Claims (2)

An adhesive composition comprising polychloroprene rubber Nairit DP, butylphenol-formaldehyde resin 101 K, water, zinc oxide, magnesium oxide, an organic solvent, which is a mixture of ethyl acetate and nefras, and a phosphorus-nitrogen-containing modifier, characterized in that the reaction product of dicyandiamine with dimethylphosphite is used as a phosphorus-nitrogen-containing modifier in an environment of 50 wt.% phosphoric acid, previously applied to carbon microfibers at a mass ratio of carbon microfibers: 5 wt.% aqueous solution of a modifier = 10:1-5, with the following ratio of composition components, parts by weight: Polychloroprene rubber Nairit DP 90.0 Butylphenol formaldehyde resin 101 K 90.0 Water 3.0 Zinc oxide 5.0 Magnesium oxide 11.0 Organic solvent 800.0 Carbon microfibers with applied modifier 10.0