JPH0657910B2 - Method for adhering rubber compound and organic fiber - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for adhering a rubber compound and an organic fiber.

2. Description of the Related Art Generally, for the adhesion between rubber and organic fiber, a method of treating the fiber with a mixture of resorcin-formalin resin and latex, which is called RFL liquid, and then vulcanizing it in close contact with unvulcanized rubber is generally adopted Has been done. However, in such a method, it is necessary to change the latex component according to the type of rubber from the viewpoint of compatibility and the like. Further, in the adhesion of ethylene-propylene copolymer rubber, hydrogenated nitrile rubber, fluorine rubber, silicone rubber, etc., these rubbers have no unsaturated bond in the molecule or a functional group effective for adhesion is used. Because of this, the RFL method cannot achieve sufficient adhesion with the fiber.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention The inventors of the present invention have conducted extensive studies to solve the above-mentioned problems in the adhesion between a rubber compound and an organic fiber, and as a result, have developed a polyepoxy compound having two or more epoxy groups in the molecule. After treating the organic fiber with a silane coupling agent having a carbon-carbon unsaturated bond such as a methacryl group in the molecule, it is treated with an unvulcanized rubber compound containing an organic peroxide. By adhesion vulcanization with, natural rubber and synthetic rubber, especially, the above-mentioned difficult-to-adhere ethylene-propylene copolymer rubber, hydrogenated nitrile rubber, fluorine rubber, silicone rubber, etc. The present invention has been completed by finding that strong adhesion can be realized between the two.

Means for Solving the Problems The present invention relates to a method for adhering a rubber compound and an organic fiber, wherein the organic fiber is treated with an epoxy compound having two or more epoxy groups in the molecule, and then the general formula YSiX ₃ ( In the formula, Y represents an organic functional group having a vinyl group, a methacryl group or an allyl group, X represents a halogen, an alkoxy group or an acyl group, and X may be the same as or different from each other. In the method of the present invention, the silane coupling agent is treated with an unvulcanized rubber compound containing an organic peroxide, followed by vulcanization. The polyepoxy compound having is not particularly limited, but preferred specific examples thereof include polyhydric alcohols such as ethylene glycol, glycerin, sorbitol, and pentaerythritol. Calls and, and reaction products of halogen-containing epoxy compounds such as polyalkylene glycol and epichlorohydrin, such as polyethylene glycol,
Resorcin, bis (4-hydroxyphenyl) dimethylethane, phenol formamide resin, resorcin
Mention may be made of polyvalent phenols such as formamide resins and reaction products of phenolic resins with halogen-containing epoxy compounds such as epichlorohydrin.

In the method of the present invention, these epoxy resins are usually brought into solution and treated by dipping the organic fibers in such a solution. Then, the organic fiber is heat-treated. This heat treatment may be carried out at a temperature sufficient for reaction-fixing the epoxy compound attached to the organic fiber, although it depends on the type of organic fiber used, and it is usually carried out at 160 to 250 ° C. for several minutes.

The organic fiber treated with the epoxy compound is then treated with a silane coupling agent.

The silane coupling agent used in the present invention is represented by the general formula YSiX ₃ (wherein Y represents an organic or inorganic functional group having a carbon-carbon unsaturated bond, X represents a halogen, an alkoxy group or an acyl group, and X represents a mutual group). May be the same as or different from each other.).

As the silane coupling agent, those in which Y is an organic functional group having a vinyl group, a methacrylic group or an allyl group and X is chlorine are preferably used.

Specific examples of such silane coupling agents include, for example, vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxy. Examples thereof include propyltris (β-methoxy) silane and vinyltriacetoxysilane.

In the method of the present invention, these silane coupling agents are also usually made into a solution using water and alcohol as a solvent and treated by immersing the organic fiber in such a solution.

In the method of the present invention, after drying the organic fiber treated with the silane coupling agent, by adhesively vulcanizing with an unvulcanized rubber compound containing an organic peroxide, such a rubber compound is obtained. A strong bond with the organic fibers can be achieved. However, in the present invention, the conditions for vulcanization adhesion are not particularly limited, and may be the usual conditions known for each rubber compound.

In the method of the present invention, as the organic fiber, typically, cotton, human silk, polyvinyl alcohol fiber, aliphatic and aromatic polyamide fiber, polyester fiber and the like can be mentioned, but are not particularly limited. Instead, it includes all organic fibers traditionally used for bonding with rubber.

Further, the rubber to which the method of the present invention can be applied may be either a natural rubber or a synthetic rubber, as long as it is a rubber capable of being crosslinked with an organic peroxide, and is not particularly limited, but, in particular, In the method of the present invention, as rubber,
Natural rubber, butadiene rubber, isoprene rubber, styrene-butadiene copolymer rubber, acrylonitrile-butadiene copolymer rubber, ethylene-propylene copolymer rubber, chlorosulfonated polyethylene rubber, hydrogenated nitrile rubber, urethane rubber, silicone rubber, Fluorine rubber can be used.

The organic peroxide is not particularly limited and may be any conventionally known one, for example, di-t-butyl peroxide, t-butyl cumyl peroxide, dicumyl peroxide. Oxide, α, α'-
Bis (t-butylperoxy) -p-diisopropylbenzene, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, 2,5-dimethyldi (t-butylperoxy) hexyne-3, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, t-butylperoxyisopropyl carbonate, 1,1-bis (t-butylperoxy) -3,5,5-trimethylcyclohexane, etc. be able to.

The amount of the organic peroxide compounded in the unvulcanized rubber compound is 0.0005 mol or more, preferably 0.001 mol or more, based on 100 g of the rubber. When the amount of the organic peroxide compounded into the rubber is less than 0.0005 mol per 100 g of the rubber, strong adhesion cannot be obtained between the rubber compound and the fiber. However, when the blending amount of the organic peroxide in the rubber blend is too large, the vulcanized rubber obtained becomes inferior in practical physical properties, for example, the elongation decreases, or the hardness excessively increases. In the present invention, the amount of the organic peroxide compounded in the unvulcanized rubber compound is usually 0.05 mol or less, preferably 0.01 mol or less, based on 100 g of the rubber.

In the method of the present invention, the rubber compound may contain a vulcanizing agent such as sulfur or triazine, in addition to the above-mentioned organic peroxide. In the case of chloroprene rubber,
It may contain a metal oxide. Furthermore, vulcanization accelerators such as thiazoles, dithiocarbamates, thiurams and thioureas may be contained. Moreover, usually
It may contain appropriate amounts of various reinforcing fillers, antioxidants, plasticizers, vulcanization aids, processing aids and the like known as rubber compounds. The rubber compound may also contain ethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, bismaleimide, etc. as co-crosslinking agents.

EFFECTS OF THE INVENTION As described above, according to the method of the present invention, an organic fiber is treated with an epoxy compound having two or more epoxy groups in the molecule, then treated with a silane coupling agent, and then treated with an organic compound. By adhesion-vulcanizing with an unvulcanized rubber compound containing a peroxide, strong adhesion can be obtained between the rubber compound and the organic fiber.

In the method of the present invention, the organic fiber is modified and activated by the treatment of the organic fiber with a polyepoxy compound, although it is not limited by any adhesion mechanism. A silane coupling agent having a group or an allyl group is firmly fixed on the organic fiber, and in vulcanization adhesion, a radical is generated in the rubber by the organic peroxide, and the rubber molecules are cross-linked with each other. At the same time, it is considered that the unsaturated bond in the silane coupling agent and the radical in the rubber molecule react to firmly bond the rubber and the organic fiber.

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

Example 1 1500 D / 2 for each of the treatment liquids A to D shown in Table 1.
Ax3 aromatic polyamide fiber cord (Technola manufactured by Teijin Ltd.) was dipped and heat-treated at 210 ° C. for 1 minute, then the second
Silane coupling shown in the table It was immersed in the agent solution a and heated at 100 ° C. for 1 minute to be fixed on the fiber cord.

After the fiber cord thus treated was brought into close contact with the sheet of the unvulcanized rubber composition 1 having the composition shown in Table 3, 16
It was vulcanized at 0 ° C. for 20 minutes to obtain an adhesive.

With this peeling tester, pulling speed 100 mm
The adhesive strength was measured in minutes. The results are shown in Table 4.

For comparison, without treatment with the epoxy compound solution,
The results obtained by only treating with the silane coupling agent a are also shown in Table 4. Fiber cord It is shown that good adhesion with rubber cannot be obtained even when treated with the Ranka coupling agent alone.

Example 2 The same fiber cord as in Example 1 was dipped in the epoxy compound solution A shown in Table 1, heat-treated at 210 ° C. for 1 minute, and then dipped in the silane coupling agent solution a shown in Table 2 for 10 minutes.
The fiber cord was fixed by heating at 0 ° C. for 1 minute.

Also, the same fiber cord as in Example 1 was similarly immersed in the epoxy compound solution A, heat-treated at 210 ° C. for 1 minute, and then immersed in the RFL liquids h to j having the composition shown in Table 5, 23
The fiber cord was fixed by heating at 0 ° C. for 1 minute.

The fiber cord thus treated was adhered to the sheets of unvulcanized rubber compounds 1 to 11 having the composition shown in Table 3 and unvulcanized rubber compounds 12 to 15 having the composition shown in Table 6 above. After that, it was vulcanized at 160 ° C. for 20 minutes to obtain an adhesive.

The adhesive strength of this adhesive was measured in the same manner as in Example 1. The results are shown in Table 7.

The fiber cord treated with the epoxy compound solution produced strong adhesion with all rubber compounds containing organic peroxide, but the fiber cord treated with the RFL solution The cord was able to give good results only for some rubber compounds.

Example 3 The same fiber cord as in Example 1 was dipped in the epoxy compound solution A shown in Table 1, heat-treated at 210 ° C. for 1 minute, and then dipped in the silane coupling agent solutions a to g shown in Table 2,
The fiber cord was fixed by heating at 100 ° C. for 1 minute.

After the fiber cord thus treated was brought into close contact with the sheet of the unvulcanized rubber composition 1 having the composition shown in Table 3, 16
It was vulcanized at 0 ° C. for 20 minutes to obtain an adhesive.

The adhesive strength of this adhesive was measured in the same manner as in Example 1. The results are shown in Table 8.

It is shown that a strong bond is obtained by treating the fiber cord with a silane coupling agent having a carbon-carbon unsaturated bond.

Claims (2)

[Claims] 1. In a method for adhering a rubber compound and an organic fiber, the organic fiber is treated with an epoxy compound having two or more epoxy groups in the molecule, and then a compound of the general formula YSiX ₃ (wherein Y is a vinyl group). , An organic functional group having a methacryl group or an allyl group, X is a halogen, an alkoxy group or an acyl group, and X may be the same or different from each other. A method for adhering a rubber compound and an organic fiber, which comprises, after treatment, vulcanizing the compound by adhesion with an unvulcanized rubber compound containing an organic peroxide. 2. The method for adhering a rubber compound and an organic fiber according to claim 1, wherein the organic fiber is a fiber cord.