JPS59174626A - Method for suppressing premature vulcanization of halogen-containing elastomer - Google Patents

Abstract

PURPOSE:To suppress the premature vulcanization of a halogen-containing elastomer without degrading the physical properties of the vulcanized product, by carrying out the vulcanization of the elastomer with di- or trithiol-epsilon-triazine compound in the presence of a polybasic carboxylic acid having mutually approachable two or more COOH groups. CONSTITUTION:A halogen-containing elastomer (e.g. epihalohydrin rubber) is vulcanized with a di- or trithiol-epsilon-triazine compound {e.g. the compound of formula [X and Y are H, alkali metal or alkaline earth metal; R is OR1, SR1 or NR1R2 (R1 and R2 are H, (substituted) 1-20C hydrocarbon group or together form a ring)]}. In the above process, preferably 0.3-5pts.wt., based on 100pts.wt. of the halogen-containing elastomer, of a polybasic carboxylic acid compound having two or more mutually approachable COOH groups (e.g. oxalic acid, glutaric acid, o-phthalic acid, etc.) is used as an agent for suppressing premature vulcanization.

Description

DETAILED DESCRIPTION OF THE INVENTION In the present invention, when vulcanizing a halogen-containing elastomer using a di- or trithiol-8-triazine compound,
The present invention relates to a method of suppressing early vulcanization of the elastomer by providing a polycarboxylic acid compound having at least two mutually accessible carboxyl groups.

The trithiol-8-triazine compound is effective as a vulcanizing agent for halogen-containing elastomers, and has improved heat aging resistance and mold staining resistance compared to conventional vulcanization methods, resulting in good compression and permanent properties. Although known to impart strain properties, compounded compositions using this vulcanizing agent may cause premature vulcanization depending on molding conditions.

Therefore, an object of the present invention is to provide a vulcanization method that suppresses early vulcanization of a halogen-containing elastomer by a di- or trithiol-8-triazine compound.

This object of the present invention is to coexist a polycarboxylic acid compound having at least two mutually accessible carboxyl groups when vulcanizing a halogen-containing elastomer using a di- or trithiol-6-triazine compound. achieved by.

The halogen-containing distomer used in the present invention includes:
A polymer of epihalohydrin or a copolymer of epihalohydrin and other epoxides, etc. with a chlorine-containing monomer such as epihalohydrin rubber, ethyl acrylate tovinylchloroacetate, or vinylbenzylchloroacetate, as desired. Chlorinated acrylic rubber, which is a copolymer with other acrylates, depending on! Examples include X-polyethylene, chlorosulfonated polyethylene, and 10-genated butyl rubber.

The di- or trithiol-5-) riazine compound has the general formula % (X and Y are hydrogen, alkali metal or alkaline earth metal; R is OR, SR, NR, R,; R and R3 are hydrogen or a hydrocarbon residue having 1 to 20 carbon atoms which may contain a substituent, and R and R may be connected at the other end to form fR. Here R8
and R, include alkyl groups such as methyl, ethyl, butyl, and ethylhexyl, cycloalkyl groups such as cyclohexyl, aralkyl groups such as hensyl, methylbenzyl, and ethylbenzyl, phenyl, naphthyl, and butylphenyl. , hydroxy-di-t-
Examples include any aryl group or substituted aryl group such as butylphenyl, and alkenyl groups such as allyl and oleyl. Examples of the ring in which R and R3 are connected at the other end to form another ring include morpholino, piperidyl, bibecoryl, and the like.

Specific examples of the compound include trithiocyanuric acid; 2-
Methoxy-12-ethoxy-12-7 dinoxy,
Butylamino-12-anilino-12-naphthylamino-12-dimethylamino-12-diethylamino-12
-dibutylamino-12-diphenylamino-, 2-dicyclohexylamino-12-morpholino or 2-piperidyl-4,6-sithio-8-triazine; sodium salt, potassium salt, calcium salt, magnesium salt, barium of these triazines Examples include salt.

The polyvalent carboxylic acid compound having at least two or more mutually accessible carboxyl groups used in the present invention is a compound having a structure in which two or more carboxyl groups can form an acid anhydride within the molecule. A chain aliphatic compound having up to 20 carbon atoms, a compound having an aromatic ring such as a benzene ring, a naphthalene ring, a pyridine ring, a furan ring, and an alicyclic ring having a cyclopentane ring, a cyclopentene ring, a cyclohexane ring, etc. This corresponds to compounds of this group. These compounds can contain oxygen atoms, sulfur atoms, nitrogen atoms, or multiple bonds as appropriate in their molecular chains, and hydrogen atoms in the molecules can be replaced with halogens as long as it does not adversely affect performance. It can also be replaced with any substituent such as an atom, an alkyl group, an alkoxy group, an acyl group, a hydroxyl group, a nitrile group, or an amino group.

More specifically, examples of aliphatic compounds having at least two mutually adjacent carboxyl groups include oxalic acid, malonic acid, methylmalonic acid, ethylmalonic acid, succinic acid, methylsuccinic acid, chlorosuccinic acid, dibromosuccinic acid, Malic acid, curtaric acid, methylglutaric acid, propane-1,Z5-tricarboxylic acid, citric acid, adipic acid, ethyl adipic acid, maleic acid, methylmaleic acid,
Chloromaleic acid, bromomaleic acid, itaconic acid, citraconic acid, 7-sglutaconic acid, aconitic acid, cis-
Compounds with aromatic rings such as α-dihydromuconic acid and cis-cismuconic acid include 〇-phthalic acid, 3-methyl-〇-7talic acid, 4-methyl-〇-7talic acid, 3-ethyl-〇 -7thalic acid, 3-butyl-0-phthalic acid, 6-
Octero-0-7furic acid, 3-chloro-0-7talic acid,
4-chloro-0-7talic acid, 4.5-dichloro-〇-7
Taric acid, tetrachloro-〇-fumeric acid, tetrabromo-
〇-7thalic acid, 4-nitro-〇-phthalic acid, 4.5-sinitro〇-phthalic acid, homophthalic acid, -methylhomo7
Talic acid, hemimellic acid, trimellitic acid, merophonic acid,
Examples of the alicyclic compounds include pyromellitic acid, naphthalene-12-dicarboxylic acid, naphthalene-2,5-dicarboxylic acid, and cis-12-cyclohexenedicarboxylic acid, trans-12-cyclohexenedicarboxylic acid, etc. The amount of each compound used per 100 parts by weight of the halogen-containing elastomer is usually 0.1 to 10 parts by weight of the di- or trithiol-8-triazine compound.
Parts by weight are preferably 0.5 to 5 parts by weight, and 01 to 10 parts by weight of polyhydric carboxylic acid compounds having at least two or more mutually adjacent carboxyl groups, preferably 0.3 to 5 parts by weight.

During vulcanization in the present invention, in addition to the above compounds, reinforcing agents, fillers, softeners, plasticizers, vulcanization aids (such as metal chlorides, hydroxides, carbonates, and organic acid salts) may be used as necessary. etc.), anti-aging agents and stabilizers may also be present. Vulcanization time is usually 100 to 18
It takes several minutes to several hours at 0C.

The early vulcanization inhibitor of the present invention has far less adverse effect on vulcanized physical properties such as tensile properties and compression set than known ones, and is of high industrial value in this respect as well.

Next, the present invention will be specifically explained using examples.

Parts of elastomer and compounding agents in each example are by weight.

Example 1 Shrimp chlorohydrin-ethylene oxide copolymer rubber (
...-Cures product [...-Kura-〇-85J) 10
0 parts, 2 parts of stearic acid, 40 parts of FBF carbon, 3 parts of magnesia, 5 parts of calcium carbonate, 0.9 parts of 2.4.6-) ripplecapto-8-to-9, and 0.9 parts of the polyvalent compound shown in Table 1. The Mooney scorch time of a rubber composition obtained by kneading 2 parts of carboxylic acid with a roll was measured. The results are shown in Table 1.

Example 2 The same test as in Example 1 was conducted, except that the halogen-containing elastomer was epichlorohydrin-ethylene oxide-allyl glycidyl ether terpolymer rubber (Zekron 61001, manufactured by Nippon Zeon Co., Ltd.). The results are shown in Table 2.

Table 2) Example 3 Epichlorohydrin-ethylene oxide copolymer rubber (
A blend of Percules' product "Burklar-0-85J" was prepared according to the following formulation, and then heated at 160C for 3
A vulcanizate was prepared by pressurizing and heating for 0 minutes. The characteristics of the vulcanizate were measured in accordance with J.E.I.K.-6501. The results are shown in Table 3.

Combination prescription Barkler-〇-85100 Stearic acid 2FE
F Carbon 40 Magnesia 6 Calcium Carbonate 52.4.6-
Drimerkabuto 8-Triazine 0.9 Nickel dibutyldithiocarbamate 1 Cyclohexylthiophthalimide 1 Polyhydric carboxylic acid compound (see Table 6) 1 From Table 6 and Table 3, early vulcanization can be suppressed by using a polycarboxylic acid compound. It can be seen that the vulcanizate thus obtained exhibits tensile properties equivalent to those without the addition of the polyhydric carboxylic acid compound. Although the compression set is slightly higher than that of the comparative example, considering that it would be much higher if a normal early vulcanization inhibitor was used, the compression set of the present invention's polyvalent It can be seen that carboxylic acid is an extremely excellent early vulcanization inhibitor.

Example 4 Shrimp chlorohydrin-ethylene oxyto copolymer rubber (
Percules product [Barkler-0-85J) 100 parts, stearic acid 2 parts, FF:F carb 40 parts, magnesia 5 parts, calcium carbonate 5 parts, 2-dibutylamino-
2 parts of 4,6-dimercabuto 8-triazine and O
An experiment similar to Example 1 was conducted using no addition or 2 parts of -7 talic acid. The results are shown in Table 4.

Table 4 Example 5 Chlorinated acrylic rubber (product of Nippon Zeon Co., Ltd. [Niball A
R71J,) 100 parts, stearic acid 1 part, MAF carbon 50 parts, magnesia 3 parts, morpholine disulfide 1 part, 2.4.6-) dimercapto-8-to9 ph9
An experiment similar to Example 1 was conducted using 21.5 parts and 0-7 talic acid without addition or 2 parts. The results are shown in Table 5.

Table 5 Example 6 A composition of epichlorohydrin-ethylene oxide-allyl glycidyl ether terpolymer rubber (manufactured by Nippon Zeon Co., Ltd. [Zeklon 3100J) with the formulation shown in @6fUK was prepared by roll cross-wiring, and the Mooney scorch time of this product was And the vulcanization torque was measured using an oscillating disk rheometer. The results are shown in Table 6.

[In the 2-mercagtoimidazoline vulcanization system, although a scorch improvement effect is seen by adding malic acid, the torque is low even after 30 minutes, indicating that vulcanization is slow. On the other hand, 2.4.6-) IJ mercapto-〇- of the present invention
In the triazine vulcanization system, the addition of malic acid has an effect of improving ciscoach, and there is little delay in vulcanization.

Patent applicant: Zeon Corporation

Claims (1)

[Claims] Di- or trithiol-8- halogen-containing elastomer
A method for suppressing early vulcanization of a halogen-containing distomer, which comprises coexisting a polycarboxylic acid compound having at least two mutually accessible carboxyl groups during vulcanization using a triazine compound.