JPH0257020B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for manufacturing a laminate having a fluororubber layer. More specifically, the present invention relates to a method for producing a laminate of a fluororubber layer and a halogen-containing rubber or a rubber layer having an unsaturated bond, which are firmly vulcanized and bonded without an intermediate layer or adhesive. In recent years, requirements for the performance of rubber materials have become stricter year by year, and the types of rubber materials used are also changing. Among rubbers, fluorocarbon rubber has outstanding performance compared to other special rubbers in terms of solvent resistance, heat resistance, chemical resistance, and weather resistance.
Demand for it is increasing year by year in the fields of industrial supplies, automobiles, and aircraft. However, its use is limited because it is very expensive compared to other rubbers, and its high specific gravity causes a significant increase in product price. It can be said that it has become difficult to satisfy these conflicting demands of high performance and low cost at the same time with a single type of rubber material. Therefore, in response to such demands, methods have been proposed in which fluorocarbon rubber is mixed with other rubbers or in which they are laminated. However, in the former case, it is difficult to obtain a uniform mixing state, and sufficient performance has not yet been achieved. In addition, in the case of lamination, apart from adhesion between unvulcanized rubber compounds, there is also a need for vulcanized rubber and unvulcanized rubber, which have become increasingly demanding due to the diversification of uses and processing methods in recent years. Since the adhesion strength at the interface is weak, it is extremely difficult to obtain a good laminate. Therefore, the present inventor developed a laminate in which one of the layers is a vulcanized rubber layer, in which it has been difficult to obtain good adhesive strength than conventionally in a laminate of a fluoro rubber layer and another rubber layer. As a result of repeated studies focusing on the manufacturing method, it was discovered that a laminate with excellent adhesive strength could be obtained by containing a specific vulcanizing agent system in each rubber layer, and the present invention was achieved. That is, the present invention provides a vulcanized rubber layer obtained from a compound containing a fluororubber, a di- or trithiol-S-triazine compound, and an onium salt, and a halogen-containing rubber other than fluororubber or a rubber having an unsaturated bond. , an unvulcanized rubber layer containing a di- or trithiol-S-triazine compound, and an onium salt, and bonded by heating, or Bringing the sulfur rubber layer into contact with a vulcanized rubber layer obtained from a halogen-containing rubber other than fluororubber or a rubber having an unsaturated bond, a compound containing a di- or trithiol-S-triazine compound, and an onium salt, The present invention provides a method for producing a rubber laminate characterized by heat bonding. As the fluororubber in the present invention, common ones can be used, such as single or copolymerized ethylene tetrafluoride, propylene hexafluoride, chlorinated ethylene trifluoride, vinyl fluoride, and vinylidene fluoride. Typical examples include copolymers of these monomers and copolymers of other monomers. Examples of halogen-containing rubbers other than fluoro rubber include chlorinated polyethylene, chlorosulfonated polyethylene, chloroprene rubber, epichlorohydrin homopolymers or copolymers, chlorinated butyl rubber, brominated butyl rubber, and chlorinated acrylic rubber. In addition, as a rubber with unsaturated bonds,
Polymer and copolymer rubbers made from monomers having α,β-ethylenically unsaturated double bonds, including polybutadiene, styrene-butadiene copolymers,
Representative examples include rubbers such as acrylonitrile-butadiene copolymer, natural rubber, polyisoprene, propylene-butadiene copolymer, and ethylene-propylene-diene terpolymer. The di- or trithiol-S-triazine compound has the general formula [R is OR ₁ , SR ₂ , NR ₃ , R ₄ , R ₁ , R ₂ ,
R ₃ and R ₄ are the same or different and are a hydrogen atom or an organic residue, and M is a hydrogen atom or a monovalent or divalent metal. Here R ₁ , R ₂ , R ₃ ,
Examples of when R ₄ is an organic residue include an alkyl group, an aryl group, an arylalkyl group, an alkylaryl group, an alkenyl group, a cycloalkyl group, and a naphthyl group. It can also have atoms such as.
Further, as a specific example when M is a metal,
Na, K, Li, 1/2Ca, 1/2Mg, 1/2Ba, 1/2Sr,
Examples include 1/2Zn, 1/2Ni, and 1/2Cu. More specifically, R is _-OCH3 , _{-OC5H5 ,} -
SH _, -N( _C2H5 ) ₂ , -N( _C4H9 ) ₂ , _{-N ( C11H23} ) ₂
,
-NH( _{C6H5 )} , -N _{( C2H5} )( _C6H5 ), _{-N
( C6H5} ) ₂ , -N _{( C6H11} ) ₂ ,

【formula】

[Formula] -NHC ₆ H ₄ NHC ₆ H ₅ , -NHC ₆ H ₄ N(C ₆ H ₅ ) ₂ , -N(i-C ₃ H ₇ )
C ₆ H ₄ NHC ₆ H ₅ , -NHC ₆ H ₂ (t-C ₄ H ₉ ) ₂ OH, -
NHC ₆ H ₂ (CH ₃ ) (t-C ₄ H ₉ )OH, -SC ₆ H ₂ (t-
C ₄ H ₉ ) ₂ OH, etc. Since fluororubber has extremely low crosslinking reactivity, compounds with high dissociation properties are preferred, for example, those in which R is dialkylamino such as dibutylamino and M is a hydrogen atom. The onium salt in the present invention has the general formula (X is P or N, Y is halogen,
At least one of R ₁ , R ₂ , R ₃ , and R ₄ is a hydrocarbon residue having 1 to 20 carbon atoms that may include a substituent, and the others may be a primary to tertiary amino group or a fluoroalkyl group. ) and complex salts of this compound. Here, the hydrocarbon residues constituting R ₁ , R ₂ , R ₃ , and R ₄ include methylethyl, propyl,
Alkyl groups such as butyl, ethylhexyl, dodecyl, cycloalkyl groups such as cyclohexyl,
Aralkyl groups such as benzyl and methylbenzyl,
Examples include aryl groups or substituted aryl groups such as phenyl, naphthyl, and butylphenyl. 2
Examples of ~tertiary amino groups include methylamino, ethylamino, anilino, dimethylamino, and diethylamino, and examples of fluoroalkyl groups include trifluoromethyl, tetrafluoropropyl, and octafluorobentyl. Specific examples of the above compounds include tetrapropyl, tetrabutyl, tetraoctyl, methyltrioctyl, butyltrioctyl, phenyltributyl, benzyltributyl, benzyltricyclohexyl, benzyltrioctyl, and butyltributyl. enyl-, octyltriphenyl-, benzyltriphenyl-, tetraphenyl-, diphenyldi(diethylamino)-phenylbenzyldi(dimethylamino)-, phenylbenzyldi(diethylamino)-trifluoromethylbenzyl-,
Examples include tetrafluoropropyltrioctyl-phosphonium or ammonium chloride or bromide. In addition, as complex salts, the above compounds and boron trihalide, sulfuric acid, sulfite,
Examples include salts with carbonic acid, silicic acid, carboxylic acid, etc. The amount of each component used is 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight of the di- or trithiol-S-triazine compound per 100 parts by weight of rubber in each layer.
The amount of onium salt is 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight. It should be noted that other common vulcanizing agents for rubber used in the present invention may be used in combination, and reinforcing agents, fillers, softeners, plasticizers, anti-aging agents, processing aids, etc. may also be used as appropriate. Can be done. In particular, -N=N- group in the compound or molecule of a group A, B, B or A metal of the periodic table which is commonly used for promoting vulcanization, improving adhesive strength or stabilizing rubber; -S-S- group or>
It is preferable to use a compound containing an N-S- group in combination for the same purpose as usual. Specific examples of the former metal compounds include magnesium, calcium, zinc, silicon, lead oxides, lithium, sodium, potassium, magnesium,
Calcium, strontium, barium, zinc hydroxide, sodium, potassium, magnesium, calcium, strontium, barium, zinc, lead carbonate, magnesium, barium, lead silicate, magnesium, lead phosphite, Organic acid salts such as acetates, cabrylates, octylates, laurates and stearates of sodium, potassium, calcium, barium, zinc, tin, and lead may be mentioned. Among these, magnesium oxide, calcium oxide, calcium hydroxide, barium stearate, etc. are practically preferred. The amount used is from 0 to 20 parts by weight, preferably from 0.2 to 10 parts by weight, per 100 parts by weight of each rubber. Also, the latter -N=N-, -S-S- or >N
As a compound having -S-,

[Formula] NH ₂ OCN = NCONH ₂ .

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[Formula] etc. The amount used is 0 to 10 parts by weight, preferably 0.5 to 5 parts by weight, per 100 parts by weight of each rubber. After mixing and kneading the above-mentioned components with each rubber using a roll, Banbury, etc., one of the resulting compounds is vulcanized by a conventional method, and then laminated with the other unvulcanized rubber compound, under the desired heating conditions (usually
By bonding at 100 to 250°C for 1 minute to 10 hours, a strongly bonded rubber laminate can be obtained. Since the rubber laminate of the present invention is manufactured from a vulcanized rubber layer and an unvulcanized rubber layer, it can be suitably used in applications and processing methods that have been considered difficult to apply in the past. Next, the present invention will be specifically explained using examples.
Note that the number of parts used for each component is based on weight unless otherwise specified. The peel test was conducted according to JIS K6829, and the tensile test was conducted according to JIS K6301. Example 1 Fluororubber compounds A and B and epichlorohydrin rubber compound C were prepared according to the formulations shown in Table 1.
A vulcanizate was obtained by preparing a portion of each sample D and press heating at 160° C. for 10 minutes. Next, the vulcanized product of A or B and the unvulcanized product of C or D, and the unvulcanized product of A or B and the vulcanized product of C or D are press-heated at 160°C for 30 minutes to bond them by vulcanization. I went there. The results are shown in Table 2.

【table】

【table】

[Table] Example 2 The same experiment as in Example 1 was conducted except that acrylonitrile-butadiene rubber formulations E and F shown in Table 3 were used instead of formulation C in Example 1. The results are shown in Table 4.

【table】

【table】

[Table] Example 3 The tensile properties and peel strength of a laminate obtained in the same manner as in Example 1 except that the formulations shown in Table 5 were used were measured. The results are shown in Table 6.

【table】

[Table] *The box shows the case where no onium salt is added.Example 4 2-dibutylamino-4,6-dithiol-S-triazine in formulations B and C of Example 1 is replaced with 2,4,6-trithiol-S. The same experiment as in Example 1 was carried out except that the formulations B' and C' were used instead of -triazine. The results are shown in Table 7.

【table】

Claims (1)

[Scope of Claims] 1. A vulcanized rubber layer obtained from a compound containing fluororubber, a di- or trithiol-S-triazine compound, and an onium salt, and a halogen-containing rubber other than fluororubber or an unsaturated bond. A method for producing a rubber laminate, which comprises bringing the rubber, di- or trithiol-S-triazine compound, and an unvulcanized rubber layer containing an onium salt into contact with each other and bonding them together by heating. 2 An unvulcanized rubber layer containing a fluororubber, di- or trithiol-S-triazine compound and an onium salt, and a halogen-containing rubber other than fluororubber or a rubber having an unsaturated bond, di- or trithiol-S
- A method for producing a rubber laminate, which comprises bringing a vulcanized rubber layer obtained from a compound containing a triazine compound and an onium salt into contact with each other and bonding them together by heating.