JPH0832863B2 - Adhesive composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a two-component adhesive composition, and more specifically, to various organic and inorganic materials used for automobiles, industrial machines, agricultural machines, ship-related materials and the like. The present invention relates to a two-component adhesive composition having excellent adhesiveness and heat stability between a material and a rubber for a composite product obtained by vulcanizing and bonding an unvulcanized rubber.

(Prior Art) Conventionally, as representatives for vulcanizing and adhering metal and unvulcanized rubber, plating materials such as brass and zinc, and adhesives such as isocyanate-based, chlorinated rubber-based, and vinylpyridine-based adhesives are known. However, they are not all-purpose and all have drawbacks. For example, a plated material such as brass or zinc is suitable for a metal having a simple shape such as a wire or a flat plate, but a metal having a complicated shape is not preferable because uniform plating is difficult. .

It has been pointed out that when an isocyanate-based adhesive or a chlorinated rubber-based adhesive is used, the adhesive surface is likely to peel off due to moisture after adhesion, while when an active crosslinking agent is contained, the thermal history during vulcanization ( There is a problem that the activity of the adhesive is lost due to (until the adhered rubber is pressed) and the adhesive is not adhered. Further, in the case of the vinyl pyridine type one-pack type, it has a drawback that it can be adhered to high hardness rubber, but it is difficult to adhere to low hardness rubber.

(Object of the Invention) The present invention has been improved by eliminating the above-mentioned drawbacks, and is capable of adhering various organic and inorganic materials and unvulcanized rubber by vulcanization and adhering to various kinds of two-pack type rubber. Moreover, it is an object of the present invention to provide an adhesive composition whose adhesive performance is stable against heat history at the time of adhesion.

(Structure of the Invention) The present invention is an essential component for an adhesive composition (A) for a base coat, which comprises vinyl pyridine / styrene / butadiene terpolymer rubber and phenol / formalin condensed phenol resin as main components, and rubber and carbon black. And an adhesive composition (B) for topcoat containing a primary and secondary vulcanization accelerator as
It exists in a two-component adhesive composition for vulcanizing and adhering various organic and inorganic materials and unvulcanized rubber.

The vinyl pyridine / styrene / butadiene terpolymer rubber used in the present invention means that the main chain double bond of the terpolymer rubber composed of vinyl pyridine, styrene and butadiene monomer (hereinafter referred to as vinyl pyridine) has halogen. A modified rubber (hereinafter referred to as a modified vinyl pyridine rubber) obtained by adding a molecule or a pseudohalogen compound, and a halogen molecule or a pseudohalogen compound used in the modification reaction is shown below.

That is, examples of the halogen molecule include chlorine, bromine and iodine, and particularly chlorine and bromine are preferably used,
Halogenated isocyanate as a pseudo halogen compound,
N-monohaloalkyl urethane, N, N-dihaloalkyl urethane, N, N-dihaloallyl sulfonamide, sulfur halide, sulfenyl halide, thiocyanogen,
Azide iodide, azide bromide, iodine chloride, iodine bromide, trichloroacetic iodide, acetic amide bromide, alkyl hypohalide, alkyl thionyl chloride, allyl thionyl chloride, nitrosyl chloride, halogenated isocyanuric acid, halogenated methyl hydantoin Etc., among them, particularly halogenated isocyanate, N, N-dihaloalkyl urethane, N, N-dihaloallyl sulfonamide, alkyl hypohalide,
Halogenated isocyanuric acid and halogenated methylhydantoin are preferably used, specifically, iodide isocyanate, N, N-dichloroethyl urethane, N, N-dibromoethyl urethane, N, N-dichloropropyl urethane, N, N. −
Dibromopropyl urethane, N, N-dichlorobenzyl urethane, N, N-dibromobenzyl urethane, N, N-dichlorobenzenesulfonamide, N, N-dibromobenzenesulfonamide, N, N-dichlorotoluenesulfonamide, N, N Compounds such as dibromotoluenesulfonamide, tertiary butyl hypochloride, trichloroisocyanuric acid, dichloroisocyanuric acid, dibromodimethylhydantoin and dichlorodimethylhydantoin.

The modification ratio of the modified vinyl pyridine rubber is preferably introduction of one halogen molecule or pseudohalogen compound per 500 to 6000 molecular weight of vinylpyridine rubber, and particularly preferably 1 halogen molecule or pseudohalogen compound per 1000 to 4000 molecular weight of vinylpyridine rubber. Introduction of molecules.

The vinyl pyridine rubber has a toughened adhesive cured film due to the above-described modification, and at the same time, has an effect of improving adhesiveness.

The phenol / formalin condensed phenolic resin used in the present invention is a low molecular weight of monohydric phenol and formalin, which is soluble in an organic solvent such as alcohol or ketone and has an average molecular weight (weight average) of 200 to 3000. Resol-type and novolak-type phenolic resins and high-molecular-weight particulate phenolic resins that are insoluble in organic solvents. Resol-type phenolic resins include pure phenol (unmodified) and alkyl-modified types. Pure phenol and modified novolak resins such as alkyl-modified, cashew oil-modified, terpene-modified, and elastomer-modified are mentioned, and cashew oil-modified novolac phenol resin is preferable.

The amount of the resol type phenolic resin and the novolak type phenolic resin used is preferably 80 to 250 parts by weight, and more preferably 100 to 200 parts by weight, based on 100 parts by weight of the vinylpyridine rubber or the modified vinylpyridine rubber. If the amount of these resins used is 250 parts by weight or more, the adhesion between the rubber and other materials becomes difficult during vulcanization adhesion, and if it is 80 parts by weight or less, the adhesion with metals becomes difficult.

The particulate phenolic resin is a resol type or novolac type, and is a spherical special phenolic resin having a primary particle size of 0.1 to 200μ, which has a high melting point of 80 to 180 ° C or is infusible. .

The particulate phenolic resin has a function of suppressing thermal softening of the adhesive film and preventing the adhesive film from flowing due to rubber pressure during vulcanization.

The amount of the particulate phenolic resin used is preferably 60 to 200 parts by weight, and particularly preferably 80 to 180 parts by weight, based on 100 parts by weight of the vinyl pyridine rubber or the modified vinyl pyridine rubber.

In the undercoat adhesive (A) of the present invention, in addition to the above-mentioned compounding ingredients, silica, titanium oxide, zinc oxide, calcium carbonate, magnesium oxide, carbon black and the like as inorganic fillers are added to 100 parts by weight of modified vinylpyridine. It is also possible to use 30 to 100 parts by weight. As the solvent, alcohols such as methyl alcohol and ethyl alcohol, ketones such as methyl ethyl ketone and methyl isobutyl ketone, cyclic ethers such as tetrahydrofuran, aromatic hydrocarbons such as toluene and xylene, halogenated compounds such as toluchloroethane and trichloroethylene. Hydrocarbons and the like can be used, and the amount used is 75 to 90% by weight in the entire adhesive composition.

The primary vulcanization accelerator of the adhesive composition (B) for topcoat used in the present invention is any one of guanidine-based, thiourea-based, thiazole-based, sulfenamide-based, thiuram-based, and dithiocarbamate-based 1 Specific examples thereof include guanidine-based compounds such as 1,3-diphenylguanidine and di-o-triguanidine; thiourea-based compounds such as N, N′-diphenylthiourea and N, N′-diethylthiourea; 2-mercapto. Benzothiazole, dibenzothiazyl disulfide, zinc salt of 2-mercaptobenzothiazole, 2- (2,4-dinitrophenylthio) benzothiazole, cyclohexylamine salt of 2-mercaptobenzothiazole, 2- (N, N-diethylthio) Carbamoylthio) benzothiazole, 2-
(Thiazoles such as 4-morpholinodithiobenzothiazole; N-cyclohexyl-2-benzothiazolylsulfenamide, N-oxydiethylene-2-benzothiazylsulfenamide, N, N-dicyclohexyl-2-
Sulfenamide compounds such as benzothiazolyl sulfenamide, N, N-diisopropyl-2-benzothiazylsulfenamide, N-tert-butyl-2-benzothiazylsulfenamide; tetramethylthylium disulfide, Thiuram compounds such as tetraethylthiuram disulfide, tetrabutylthiuram disulfide, tetramethylthiuram monosulfide, dipentamethylenethiuram tetrasulfide; zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate, zinc dibutyldithiocarbamate, N-ethyl-N-phenyldithiocarbamate Examples thereof include dithiocarbamate compounds such as zinc, and thiazole and sulfenamide compounds are preferable. Rubber 100 used
It is in the range of 1 to 4 parts by weight with respect to parts by weight.

The secondary vulcanization accelerator used in the present invention is any one of aldehyde ammonia type and aldehyde amine type, and specific examples include hexamethylenetetramine, acetaldehyde ammonia, ethyl chloride-formaldehyde-ammonia reaction product, Ethyl chloride-formaldehyde-
Aldehyde ammonia system such as a mixture of ammonia reactant and stearic acid; n-butyraldehyde-aniline condensate, butyraldehyde-acetaldehyde-butylideneaniline reactant, butyraldehyde-monobutylamine condensate, butyraldehyde-butylideneaniline reactant , Heptaldehyde-aniline reaction product, α-ethyl-
Examples thereof include aldehyde amines such as β-propylacrolein-aniline condensate, and the amount used is in the range of 5 to 15 parts by weight, preferably 7 to 13 parts by weight, based on 100 parts by weight of rubber.

By using a small amount of the primary accelerator and a large amount of the secondary accelerator together, the effect of improving the adhesiveness of the low hardness rubber can be obtained. In this case, unlike general rubber compounding, a vulcanizing agent such as sulfur is not particularly required.

The primary and secondary vulcanization accelerators are blended with rubber, carbon black and the like. The rubbers used for them are natural rubber and synthetic rubber, and synthetic rubber is polyisoprene,
Polybutadiene, styrene-butadiene copolymer rubber containing at least one or more, polyisoprene, polybutadiene, styrene-butadiene copolymer rubber single rubber system, polyisoprene / polybutadiene rubber, polyisoprene / styrene-butadiene copolymer rubber, Both a polybutadiene / styrene-butadiene copolymer rubber binary blend rubber and a polyisoprene / polybutadiene / styrene-butadiene copolymer rubber three-part blend rubber are possible, and the total amount is 100 parts by weight. .

Carbon black has a particle size in the range of 11 to 100 mμ, and specific examples include SAF, ISAF, HAF, FF, FEF, GPF, SR.
F etc. are used, and the amount used is 40 to 10 parts by weight with respect to 100 parts by weight of rubber.
It is in the range of 0 parts by weight, preferably 50 to 80 parts by weight. Further, zinc white, stearic acid, an antioxidant, a softening agent, a tackifier, a filler and the like which are usually used in rubber compounding compositions are compounded and used. Further, as a vulcanizing agent, a sulfur donor such as sulfur or phenol-based disulfide can also be used.

Hexane, heptane, and other aliphatic hydrocarbons, toluene, xylene, and other aromatic hydrocarbons, trichloroethane, trichloroethylene, and other halogenated hydrocarbons can be used as the solvent.
75 to 90% by weight.

The adhesive composition (A) for undercoating according to the present invention is prepared by mixing the modified vinyl pyridine rubber and the phenol / formalin condensed phenol resin with a kneading device such as a roll, Banbury or kneader, and then dissolving them in an organic solvent or the whole composition. It is obtained by pulverizing and dissolving with a ball mill.

The overcoat adhesive composition (B) is obtained by kneading rubber, carbon black and a vulcanization accelerator with a roll or Banbury, and then dissolving them in a solvent.

The adhesive according to the present invention is a two-pack type adhesive composition which is a combination of the undercoating adhesive composition (A) and the overcoating adhesive composition (B), and as the adherend material, iron, brass, It targets metals such as aluminum, ceramics, plastics and other organic and inorganic materials, and is particularly excellent in adhesion to iron.

The adhered rubber is natural rubber or synthetic rubber, and synthetic rubbers include isobutylene rubber, butadiene rubber, styrene-
Butadiene rubber, acrylonitrile-butadiene rubber,
Chloroprene rubber, isobutylene-isoprene rubber, ethylene-propylene-diene terpolymer, etc., is an unvulcanized rubber that is a base polymer, and it is difficult to adhere a small amount of these from high-hardness rubber such as carbon black, inorganic filler, and sulfur. It is possible to vulcanize and bond these rubbers having a wide range of hardness characteristics to various materials, including low hardness rubbers.

The adhesive composition according to the present invention is capable of adhering a wide range of rubber having a high hardness to a low hardness depending on the amounts of carbon black, an inorganic filler, sulfur and the like, and further adheres to the heat history during vulcanization. It has the advantage that the adhesive performance of the agent is extremely stable.

(Examples) The present invention will be described in more detail below with reference to Examples.

Example 1 An adhesive composition (A) for undercoating was prepared by precipitating vinyl pyridine latex 0650 manufactured by Japan Synthetic Rubber Co., Ltd. with methanol to give a solid rubber, and adding 2000 g of a vinyl pyridine rubber in a toluene solution to N, N-dichloro. 1 mol of paratoluene sulfonamide (DCTS) was added and stirred to obtain a modified vinyl pyridine rubber. With the composition shown in Table 1, resol type and novolac type phenolic resins, granular phenolic resin, silica and methyl isobutyl ketone (MIBK) / methanol = 90/10 (weight ratio) as a solvent having a solid content of 15
% So that it was pulverized and dissolved in a ball mill for 7 hours to be prepared.

The adhesive composition (B) for topcoat was prepared by kneading rubber, carbon black and zinc white in Banbury at 70 ° C according to the formulation shown in Table 1 and then adding a vulcanization accelerator with a roll at 60 ° C into toluene. After soaking for one day and night, stir with a disperser to obtain solid content
Four 15% adhesive solutions were obtained. A steel sheet (mild steel material) whose surface has been sandblasted with these adhesive solutions is first dip-coated with the adhesive composition for undercoating (A), and then with the adhesive composition for overcoating (B) by dip coating. Bonded with unvulcanized rubber reinforced with canvas shown in 3 160
After vulcanization adhesion for 15 minutes at a temperature of 50 ° C., a peeling test was performed in a 180 ° direction at a pulling speed of 50 mm / min using an Instron tensile tester to measure the adhesiveness, and the results are shown in Table 2.

As a comparative example, a commercially available two-pack type chlorinated rubber adhesive was subjected to the same adhesion test as described above. The results are as shown in Table 2. The adhered rubbers used for these adhesions are as shown in Table 3, and include carbon black, a high hardness rubber (R1) with a large amount of sulfur and a hardness of 78 ° and a low hardness rubber (a low hardness of 38 ° with a small amount of sulfur (a hardness of 38 °). R2).

From the results shown in Table 2, the adhesive composition of the present invention exhibits good adhesiveness of low hardness rubber by using a large amount of the secondary vulcanization accelerator of the adhesive composition (B) for topcoat, and has high hardness and high hardness. It has been clarified that a wide range of low hardness rubbers and metals can be vulcanized and adhered well, and it has been found to be comparable to the commercially available chlorinated rubber system.

Example 2 To examine the stability of the adhesive performance against the heat history during vulcanization of the adhesive, the same adhesive as in Example 1 was applied to a metal plate and the adhesive was heat-treated at 160 ° C. for a predetermined time. rear,
Immediately after that, vulcanization adhesion was performed together with unvulcanized rubber, and the adhesion was measured in the same manner as in Example 1. The results are as shown in Table 4.

From the results shown in Table 4, adhesives Nos. 2, 3 and 4 had a good initial adhesiveness for a long time with respect to the heat history during vulcanization up to a wide range of rubbers of high hardness and low hardness, and were commercially available It was found that the thermal stability was remarkably superior to that of the rubber adhesive.

(Advantages of the Invention) The adhesive composition according to the present invention is capable of adhering to a wide range of rubbers having a high hardness to a low hardness, and has a characteristic of being significantly superior in thermal stability to a commercially available chlorinated rubber system. .

Claims (5)

[Claims] 1. Vinyl pyridine / styrene / butadiene 3
Adhesive composition for undercoating (A) containing a main copolymer rubber and a phenol / formalin condensed phenolic resin as main components, and adhesive for overcoating containing primary and secondary vulcanization accelerators as essential components in rubber and carbon black A two-component adhesive composition comprising an agent composition (B) for vulcanizing and adhering various organic and inorganic materials and unvulcanized rubber. 2. The two-component adhesive composition according to claim 1, wherein the vinyl pyridine / styrene / butadiene terpolymer rubber is modified with a halogen molecule or a pseudohalogen compound. A composition. 3. The two-component adhesive composition according to claim 1, wherein the phenol / formalin condensed phenolic resin is soluble in an organic solvent and has a weight average molecular weight of 200 to 3000.
Total amount of low molecular weight resol type and novolac type resins of 80
˜250 parts by weight and 60 to 200 parts by weight of high molecular weight particulate phenolic resin insoluble in organic solvent. 4. The two-component adhesive composition according to claim 1, wherein the primary vulcanization accelerator is a guanidine type, a thiourea type, a thiazole type, a sulfenamide type, a thiuram type, and 1 to 4 of any one of the dithiocarbamate compounds
A composition containing parts by weight. 5. The two-component adhesive composition according to claim 1, wherein the secondary vulcanization accelerator is 5 to 15 parts by weight of one of an aldehyde ammonia system and an aldehyde amine system. The composition containing.