JPS6214568B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a vulcanizable elastomer composition, and more particularly to a vulcanizable elastomer composition that has heat resistance, low temperature brittleness resistance, and is mainly composed of a copolymer of ethylene, an acrylic ester or a methacrylic ester, and an unsaturated glycidyl ester. The present invention relates to a vulcanizable elastomer composition that also has oil resistance. In recent years, with remarkable technological advances in various industries such as automobiles, home appliances, and machinery, the characteristics required of rubber materials used in various related parts have become diverse, and various special elastomers are being developed to meet these requirements. As is well known. Among them, a bipolymer consisting of an acrylic acid ester and a butenedionic acid monoester or a terpolymer consisting of ethylene, an acrylic acid ester, and a butenedionic acid monoester described in Japanese Patent Publication No. 1977-45031 is used. Elastomer compositions containing polymer components are attracting attention because of their good low-temperature properties, high-temperature properties, and oil resistance. According to Japanese Patent Publication No. 1972-49389, the terpolymer is vulcanized to a brittle point below about -40°C, and a temperature of about 115°C.
It is described that the result is an elastomer having an oil swelling rate lower than %. However, since the butenedionic acid monoester contained in the terpolymer has a carboxylic acid group, it is said that equipment is likely to be corroded when producing the terpolymer and when vulcanizing it to produce an elastomer. It has major drawbacks. The inventors of the present invention have made extensive studies to improve these drawbacks, and have found that the problem can be solved by copolymerizing a glycidyl group-containing comonomer instead of a carboxylic acid group-containing comonomer as a vulcanization site, resulting in the present invention. That is, the present invention comprises (1) one or more comonomers selected from (a) 50 to 85 mol% ethylene, (b) 50 to 15 mol% acrylic ester or methacrylic ester; and (c) a copolymer made by copolymerizing one or more comonomers selected from 0.1 to 5 mol% of unsaturated glycidyl esters and having a melting index of 1 to 500 mg/10 minutes. (2) 1 selected from the group consisting of polyfunctional organic amines or their salts, organic carboxylic acid ammonium salts, dithio-carbamates, thiourea derivatives, and acid anhydrides;
vulcanizing agents, and (3) additives selected from the group consisting of vulcanization accelerators, fillers, and various stabilizers, which are optionally used. A sulfurable elastomer composition is provided. The first object of the present invention is to provide a vulcanizable elastomer composition having good scorch resistance, heat resistance, and oil resistance. The purpose is to avoid problems due to corrosion of equipment during manufacturing or when manufacturing elastomer compositions. The acrylic ester and methacrylic ester that are constituent components of the multi-component copolymer used in the present invention are esters consisting of alcohols having 1 to 8 carbon atoms. Specifically, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, n-butyl acrylate, n-butyl methacrylate, tert-butyl acrylate, tert-butyl methacrylate, 2-ethylhexyl acrylate, Such as 2-ethylhexyl methacrylate. The content of acrylic ester and/or methacrylic ester is 50 to 15 mol%, preferably 42 to 20 mol%, in the multicomponent copolymer composition. When the content of acrylic ester and/or methacrylic ester exceeds the upper limit, the brittle point becomes high, making it difficult to use as an elastomer at low temperatures. On the other hand, if it is lower than the lower limit, the crystallinity of the copolymer will become high, making it impossible to obtain sufficient elasticity as an elastomer. The content of ethylene used in the present invention is 50 to 85 mol% based on the composition of the multi-component copolymer,
Preferably it is 58 to 80 mol%. If the ethylene content exceeds the upper limit, the crystallinity of the copolymer will increase, making it impossible to obtain sufficient elasticity as an elastomer. Another drawback when the ethylene content exceeds the upper limit is that the oil resistance of the elastomer decreases. If the ethylene content is lower than the lower limit, the brittle point will be high, making it difficult to use it as an elastomer at low temperatures. The unsaturated glycidyl esters used in the present invention are those described in Japanese Patent Publication No. 46-45085, such as glycidyl acrylate, glycidyl methacrylate, itaconic acid dicrycidyl ester, butene tricarboxylic acid triglycidyl ester, p - Styrene carboxylic acid glycidyl ester, etc. The content of unsaturated glycidyl ester is 0.1 to 5 in the multi-component copolymer.
It is mol%, preferably 0.2 to 3 mol%. If the content of unsaturated glycidyl ester exceeds the upper limit, scorch resistance will be poor. If it is lower than the lower limit, a sufficient crosslinking effect cannot be obtained. It is also possible to copolymerize the multi-component copolymer of the present invention with other comonomers that can be copolymerized with ethylene. Specific examples include isobutylene, styrene and its derivatives, vinyl acetate, and halogenated olefins such as tetrafluoroethylene and hexafluoropropylene. The multi-component copolymer of the present invention is produced by a known method. For example, free radical initiated bulk polymerization,
It can be produced by emulsion polymerization or solution polymerization. A typical polymerization method is described in Japanese Patent Publication No. 45085-1973. For example, in the presence of a polymerization initiator that generates free radicals,
Pressure 500Kg/in the presence of a polymerization regulator if necessary
It can be produced under conditions of cm ² or more and a temperature of 40 to 300°C. The melting index in the present invention was measured at 190°C by the method of JISK6760. In the present invention, the melting index of the polycopolymer is limited to 1 to 500 g/10 minutes because if it is lower than the lower limit, the processability such as kneading processability will be poor, and if it exceeds the upper limit, the elastomer composition will be vulcanized. This is because its physical properties are inferior. The elastomer composition of the present invention has a temperature of 150 to
Good practical properties are exhibited by vulcanization at 230°C for 5 to 45 minutes, preferably at 160 to 190°C for 10 to 30 minutes. The vulcanizing agent used in the present invention is a substance consisting of one or more of polyfunctional organic amines or their salts, organic carboxylic acid ammonium salts, dithio-carbamates, or thiourea derivatives. The amount of the vulcanizing agent added is 0.05 to 1 mole of unsaturated glycidyl ester group contained in the polymer of the present invention.
It is 2.0 mol. Preferably it is 0.1 to 1.5 mol. If the amount of the vulcanizing agent added exceeds the upper limit, the tensile elongation rate will be low and the heat resistance will be poor. If the amount of the vulcanizing agent added is lower than the lower limit, a sufficient crosslinking effect cannot be obtained. Specific examples of polyfunctional organic amines used in the present invention will be given below. Aliphatic diamines such as polymethylene diamine and polyether diamine, diethylene triamine, substituted polyamines, iminobispropylamine, bis(hexamethylene) triamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, aminoethylethanolamine, methylimino Aliphatic polyamines such as bispropylamine, diamine carbamates such as ethylenediamine carbamate and hexamethylenediamine carbamate, menthanediamine, N-aminoethylpiperazine,
Alicyclic polyamines such as 1,3-diaminocyclohexane and isophorone diamine; aliphatic compounds with aromatic rings such as m-xylylene diamine and tetrachloro-p-xylylene diamine N,N'-dicinnamylidene-1,6-hexane diamine; amine, m
-phenylene diamine, diaminodiphenyl ether, 4,4-methylene dianiline, diaminodiphenylsulfone, benzidine, 4,4'-bis(0-toluidine), 4,4'-thiodianiline, 0
-phenylenediamine, dianisidine, methylenebis(0-chloroaniline), 2,4-toluenediamine, bis(3,4-diaminophenyl)sulfone, diaminoditolylsulfone, 4-chloro-0-phenylenediamine, 4 -methoxy-6-
Aromatic amines such as methyl-m-phenylenediamine and m-aminobenzylamine, secondary amines such as N-methylpiperazine, hydroxyethylpiperazine, piperidine, pyrrolidine, and morpholine, tetramethylguanidine, 2,4,6-tris Tertiary amines such as (dimethylaminomethyl)phenol and their salts. Specific examples will be given of the organic carboxylic acid ammonium salts used in the present invention. Examples include ammonium benzoate. A specific example of the dithio-carbamate used in the present invention will be given below. Zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate, zinc dibutyldithiocarbamate, N-ethyl-N
-Zinc phenyldithiocarbamate, copper dimethyldithiocarbamate, ferric dimethyldithiocarbamate, and the like. Specific examples of thiourea derivatives used in the present invention will be given below. Thiourea, N・N'-diphenylthiourea, ethylene thiourea, diethyl thiourea, dibutyl thiourea, trimethyl thiourea, dilauryl thiourea, 2-mercaptobenzimidazole, zinc salt of 2-mercaptobenzimidazole etc. Specific examples of acid anhydrides used in the present invention will be given below. Phthalic anhydride, itaconic anhydride, succinic anhydride, citraconic anhydride, alkenylic anhydride,
Dodecenylsuccinic anhydride, tricarballylic anhydride, maleic anhydride, linoleic acid adduct of maleic anhydride, maleic anhydride-vinyl ether copolymer, maleic anhydride-styrene copolymer, maleic anhydride adduct of methylcyclopentadiene, Chlorendic anhydride, alkylated endoalkylene tetrahydrophthalic anhydride, methyl disubstituted butenyl tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, pyromellitic anhydride, cyclopentanetetracarboxylic anhydride, benzophenone anhydride These include tetracarboxylic acid, ethylene glycol bistrimeritate, and glycerin tristrimeritate. In the present invention, a vulcanization reaction accelerator may be used in combination, if necessary. For example, when using polyfunctional organic amines as a vulcanizing agent, phenol,
Cresol, bisphenol, pentachlorophenol, phenolic resin, triphenyl phosphite, tri(dimethylaminomethyl)phenol, acetic acid, water, benzoic acid, oxalic acid, salicylic acid, acetonitrile, nitrobenzene, etc. are used as vulcanization reaction accelerators. can do. The elastomer of the present invention may contain anti-aging agents, softeners, plasticizers and the like, if necessary. Antioxidants include antioxidants, heat antiaging agents,
Includes crack inhibitors, ozone deterioration inhibitors, etc. Antioxidants used in the present invention include phosphorus ester antioxidants, hindered phenolic antioxidants, hindered phenolic antioxidants, and amine antioxidants.
It may be a mixture of species or more. The proportion of antioxidant in the elastomer is 0.1 per 100 parts of polymer.
~6 parts, preferably 1 to 3 parts. Even if more than 6 parts of antioxidant is blended, there is no significant improvement in the effect of preventing formation. Preferably it is 3 parts or less. Also
If the amount is less than 0.1 part, sufficient antioxidant effect cannot be obtained. Preferably it is 1 part or more. Specific examples of antioxidants are shown below. Tricresyl phosphate, tris(3,4-di-tert-butyl-4-hydroxyphenyl) phosphate, tris(mixed mono- and di-nonylphenyl) phosphite, high molecular weight poly(phenol phosphonate),
6-(3,5-di-tert-butyl-4-hydroxy)benzyl-6H-dibenz[c·e]-[1·
2] Oxaphosphorine-6-oxide, 2,5-
Di-tert-butylhydroquinone, 4,4'-dioxydiphenyl, 4,4'-thio-bis(6-tert
-butyl-m-cresol) main component, 1, 3, 5
-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, mono-tert-butyl-m-cresol,
2,6-di-tert-butyl-α-dimethylamine-P-cresol, alkylated phenol resolisyl resin, 4,4'-thiobis(3-methyl-6-tert-butylphenol), P-phenylphenol , N.N'-diphenyl-P-phenylenediamine, N.N'-di-β-naphthyl-P-phenylenediamine, low temperature reaction product of acetone and phenyl-β-naphthylamine, 4.4'-
Bis(α・α-dimethylbenzyl)diphenylamine, N-phenyl-N′-(P-toluenesulfonyl)-P-phenylenediamine, polymerized 2,2,4-trimethyl-1,2-dehydroquinoline, phenyl-β - such as naphthylamine. A filler can be used in the elastomer of the present invention if necessary. Fillers include carbon black, calcium carbonate, calcium, magnesium, carbonate, magnesium carbonate, aluminum silicate, magnesium silicate, calcium silicate,
These include silicic acid, barium sulfate, zinc sulfide, calcium sulfate, calcium sulfite, and aluminum hydroxide. Filler content is 10 to elastomer
~50% by volume, preferably 15-30% by volume. If the filler content exceeds 50% by volume, it will adversely affect the heat aging properties of the elastomer. Preferably it is 30% by volume or less. When it is less than 10% by volume, the effect of improving tensile properties by filler reinforcement is small. Preferably it is 15% by volume. The uses of the elastomer composition of the present invention include:
Examples include automobile rubber parts, industrial rubber parts, etc.
Specifically, hoses, tubes, diaphragms, sealing materials, etc. are exemplified. The effects of the present invention will be explained below with reference to Examples, but the present invention is not limited thereto. The physical properties of the compound were determined according to the method of JISK6301, and the tensile test was performed at 20°C, and the compression set test was performed under the conditions of 20℃.
The low temperature test is a JIS low temperature torsion test (refrigerant: dry ice - methanol) at 150℃ for 70 hours, and the heat aging test is a test tube heat aging test at 175℃.
Under the condition of 70 hours, the aging test in hot lubricant was performed at 150℃−
Each measurement was carried out under conditions of 70 hours. Examples 1-5 Terpolymers were manufactured using a high pressure polyethylene manufacturing process. Table 1 shows the physical properties of the terpolymer.

【table】

[Table] Vulcanizable elastomer compositions containing the terpolymers shown in Table 1 as polymer components and the formulations shown in Table 2 were vulcanized under the conditions shown in the column below.

[Table] After press vulcanization, the rubber properties shown in Table 3 were obtained. The excellent physical properties of the present invention are clear from the results shown in Table 3.

【table】

【table】

Claims (1)

[Scope of Claims] 1 (1) One or more comonomers selected from (a) 50 to 85 mol% ethylene, (b) 50 to 15 mol% acrylic ester or methacrylic ester and (c) 0.1 to 5 mol% of one or more comonomers selected from unsaturated glycidyl esters,
a copolymer having a melting index of 1 to 500 g/10 minutes; (2) a group consisting of polyfunctional organic amines or their salts, organic carboxylic acid ammonium salts, dithiocarbamates, thiourea derivatives, and acid anhydrides; one or more vulcanizing agents selected from;
and (3) a vulcanizable elastomer composition comprising an additive selected from the group consisting of various vulcanization accelerators, various fillers, and various stabilizers, which are used as necessary.