JPS6367817B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a blend rubber composition having good vulcanizable properties and adhesive properties. (Prior Art) Chlorinated polyethylene, especially chlorinated polyethylene produced by a process that includes a chlorination process near the melting point of polyethylene crystals, is a useful material as an elastomer material, and when sufficiently vulcanized,
It is known that among various synthetic rubbers, it can exhibit excellent mechanical properties, heat resistance, oil resistance, chemical resistance, and weather resistance. Vulcanization using peroxides is considered to be the typical conventional vulcanization method for chlorinated polyethylene, but this method has disadvantages in the process due to the slow vulcanization reaction under air contact, such as poor release from the mold. It has many aspects that are unacceptable in the field of conventional rubber technology, such as an increase in the defective rate due to this, and a danger in handling due to low temperature decomposition. In order to improve these drawbacks, a vulcanizable rubber composition comprising (b), (c), and (d) described in the claims above and chlorinated polyethylene as a polymer has been proposed. (Tokuko No. 54-15458,
(Japanese Patent Publication No. 54-15459) This makes it possible to obtain a good vulcanized rubber. However, at present, there has been little study on the technology of obtaining a good laminate by vulcanization adhesion with other types of rubber, which is widely practiced in the rubber industry. (Object of the Invention) An object of the present invention is to provide a chlorinated polyethylene blend rubber that has good adhesion to other rubbers, particularly NBR, epichlorohydrin rubber, and the like. (Structure of the Invention) As a result of various studies, the present inventors have found that a chlorinated polyethylene rubber compound alone is not sufficient under severe conditions to obtain good adhesion to other types of rubber as mentioned above. Heading The invention has been completed. That is, the present invention comprises (a) the following polymer components (i) and (ii) 5 to 95 parts by weight of chlorinated polyethylene. (In the formula, R ¹ represents a hydrogen atom or a C ₁ to C ₂ alkyl group, and R ² represents a hydrogen atom or a C ₁ to C ₃ alkyl group.) Chlorhydrin ether 0.1 to 5
95 to 5 parts by weight of acrylic rubber (b) Mercaptotriazines (c) Amines having a boiling point of about 110°C or higher, organic acid salts of the amines or adducts thereof, arylguanidines, condensation of aniline and aldehydes product, one or two selected from 2-benzothiazylsulfenamide of primary or secondary amine
The present invention is a blend rubber composition characterized by containing each of the above components (a), (b), (c), and (d): (d) a metal compound serving as an acid acceptor; The chlorinated polyethylene which is the polymer component (a) of the composition of the present invention is chlorinated polyethylene having any chlorine content, crystallinity, and molecular weight distribution;
In particular, amorphous or substantially amorphous chlorinated polyethylene having a chlorine content of 20 to 50% by weight is preferred. Acrylic rubber, which is another polymer component of the present invention, is
Although it contains the above-mentioned chlorvinyl ether as a copolymerization component that serves as a vulcanization point, when using acrylic rubber that contains other vulcanization points, such as acrylic rubber that has epoxy groups as vulcanization points, it is difficult to cure chlorinated polyethylene. does not occur enough. For example, when using acrylic rubber whose vulcanization point is obtained by polymerizing monochlorovinyl acetate, the vulcanization reaction is so rapid that a rubber molded article cannot be obtained in fact. Examples of monomers represented by formula () include chloromethyl vinyl ether, 1-chloroethyl vinyl ether, 2-chloroethyl vinyl ether,
1-Chlorpropyl vinyl ether, 2-chloropropyl vinyl ether, chlormethyl metavinyl ether, 1-chloroethyl metavinyl ether, 2-chloroethyl metavinyl ether, chlormethyl ethavinylether, 1-chloroethyl ethavinylether, 2-chloroethyl ethavinylether, 1-chloropropyleta vinyl ether and the like are used. Among these, 2-chloroethyl vinyl ether is most preferred. One or more of these monomers accounts for 0.1 to 5 of the total monomer weight.
It is used in a range of 0.5 to 2.0% by weight, preferably 0.5 to 2.0% by weight. If it is less than 0.1% by weight, a sufficient vulcanization effect cannot be obtained, and if it exceeds 5% by weight, the vulcanized density becomes excessive after vulcanization and rubber elasticity is lost. Examples of acrylic monomers without vulcanization points include methyl acrylate, ethyl acrylate,
Acrylates such as n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, methoxymethyl acrylate, ethoxymethyl acrylate, 2-
Alkoxy acrylates such as ethoxyethyl acrylate, alkylthioacrylates such as methylthiomethyl acrylate, ethylthiomethyl acrylate, 2-ethylthioethyl acrylate,
One or more fluorine-containing acrylates such as perfluoropropyl methyl acrylate are used. Also, vinyl chloride, vinylidene chloride, acrylonitrile, methacrylonitrile, styrene, α-
A small amount of methylstyrene, vinyl acetate, ethyl vinyl ether, butyl vinyl ether, methyl methacrylate, ethyl methacrylate, ethylene, propylene, butene-1, etc. may be copolymerized. Although such acrylic rubber can be produced by any conventionally known polymerization method, it is preferably produced by a suspension polymerization method or an emulsion polymerization method. A commercially available product of such acrylic rubber is Nippon Oil Seal Co., Ltd.'s product name "Noxtite A".
-1095'' and BF Gudzdritsu's product name ``Hycor4021''. The mercaptotriazines used as component (b) of the composition of the present invention have the general formula () below. (wherein R is selected from the group consisting of mercapto group, alkoxy group, alkylamino group, di-alkylamino group, cycloalkylamino group, dicycloalkylamino group, and arylamino group), specifically, 1,3,5-trithiocyanuric acid, 1-methoxy-3,5-dimercaptotriazine, 1-hexylamino-3,5-dimercaptotriazine, 1-diethylamino-3,5-
Dimercaptotriazine, 1-dibutylamino-
Examples include 3,5-dimercaptotriazine, 1-cyclohexylamino-3,5-dimercaptotriazine, and 1-phenylamino-3,5-dimercaptotriazine. The basic amine compound used as component (c) of the composition of the present invention, i.e., the amine having a boiling point of about 110°C or higher, is particularly suitable for aliphatic or cycloaliphatic primary, secondary or secondary amines having 5 to 20 carbon atoms. A triamine with a pk value of about 4.5 or less is preferable. Representative examples of such amines include n-hexylamine, octylamine, dibutylamine, tributylamine, trioctylamine, di(2-ethylhexyl)amine, dicyclohexylamine, hexamethylene diamine, and the like. Further, as the organic acid salt or adduct of an amine, a salt or adduct of an amine having a pk value of about 4.5 or less and an organic acid having a pk value of about 2.0 or more is preferable. Representative examples of such organic acid salts of amines include n-butylamine acetate, dibutylamine oleate, hexamethylenediamine carbamate, and dicyclohexacylamine salt of n-mercaptobenzothiazole. Examples of diarylguanidine in the basic amine compound include diphenylguanidine and ditolylguanidine. In addition, as a condensation product of aniline and aldehyde, aniline and at least one
Condensation products of the species with C1-C7 aldehydes are preferred. Specific examples include condensates of aniline and butyraldehyde, condensates of aniline and heptaldehyde, and condensates of aniline and acetaldehyde and butyraldehyde. Further, 2-benzothiazylsulfenamide, which is a primary or secondary amine, is represented by the following general formula (). (However, R ¹ and R ² may be the same or different,
A group having 1 to 12 carbon atoms selected from hydrogen, an alkyl group, a cycloalkyl group, and an aralkyl group, and having no substituent containing a hetero atom, and
R ¹ and R ² are not both hydrogen) The primary or secondary amine forming the above sulfenamide preferably has a pk value of about 4.5 or less, and specific examples include cyclohexylamine,
Butylamines, diethylamines, dipropylamines, dibutylamines, dihexylamines, dioctylamines, dilaurylamines,
These include dicyclohexylamine, piperidine, pipecoline, morpholine, and piperazine. In the composition of the present invention, the mercaptotriazine is 0.1 to 5 parts by weight, particularly preferably 0.5 to 3 parts by weight, and the component (C) amine, amine salt, or sulfenamide is 0.5 to 5 parts by weight per mole of the mercaptotriazine. It contains 3 molar equivalents. A certain kind of metal compound (d) which can serve as an acid acceptor is extremely desirable from the viewpoint of stability of vulcanizate and vulcanization rate. Metal compounds for this purpose include oxides, carboxylates, carbonates of group metals of the periodic table,
Preferred are phosphites, oxides of Group A metals, basic phosphites, basic carbonates, basic carboxylates, and the like. Compounding amount is per 100 parts by weight of polymer
0.5 to 20 parts by weight is preferred. In addition to the above compositions, various additives such as fillers, reinforcing agents, plasticizers, stabilizers, anti-aging agents, lubricants, viscosity-improving agents, pigments, hardening agents, Combustion agents, etc. can be added freely. As a method for adding each drug, a conventional method such as an open roll method or a Banbury mixer is employed.
In order to produce a vulcanized molded product using the composition of the present invention, it is usually heated to a temperature of 100 to 200°C. Although the heating time is selected depending on the temperature, the desired vulcanizate can be obtained within a time range of 5 to 120 minutes. Any method such as compression molding using a metal mold, injection molding, heating using a steam can, or an air bath can be used as the heating molding method. The present invention will be explained below with reference to Examples and Comparative Examples. Note that all compositions in each example are parts by weight and weight %. Example Comparative example (polymerization of acrylic rubber) Internal volume 5 equipped with a stirrer and temperature adjustment device
The monomer mixture shown in Table 1 was added to a glass reactor.
parts, dodecyl mercaptan (molecular weight regulator) 0.02
1 part, 2 parts of sodium dodecyl sulfate, 2 parts of polyoxyethylene dodecyl ether, and 200 parts of water, and after sufficient substitution by bubbling nitrogen gas, 0.1 part of ammonium persulfate and 0.1 part of sodium hydrogen sulfite were added to initiate the polymerization reaction. 75 parts of the remaining monomer mixture was added over about 1 hour, followed by stirring for about 1.5 hours to complete the polymerization reaction.
During this time, the temperature of the reaction solution was maintained at 60°C. The obtained polymer latex was poured into a 15% aqueous sodium chloride solution at about 80°C, and the copolymer coagulated was washed with water and dried to obtain each acrylic rubber.

【table】

[Table] (Manufacture and vulcanization of rubber compound) A rubber compound with the composition shown in Table 2 was prepared using a 7″ open roll, and the vulcanization curve was measured using a JSR-Kyulastometer at a temperature of 160°C. The acrylic rubbers of Examples 1 and 2 have vulcanization points of 2-chloroethyl vinyl ether and 2-chloropropyl vinyl ether, respectively, and exhibit good vulcanization curves.The acrylic rubber of Comparative Example 1 The acrylic rubber of Comparative Example 2 uses monochlorovinyl acetate as the vulcanization point, but the viscosity increased during roll kneading and virtually no formed product was obtained.The acrylic rubber of Comparative Example 2 had an epoxy group as the vulcanization point. However, this formulation caused significant vulcanization inhibition. Table 1 shows the initial physical properties measured according to JIS-K-6301 and the volume change rate after immersion in JIS No. 3 oil at 120°C for 70 hours. Only Examples 1 and 2 exhibit excellent processing stability, rubber physical properties, and oil resistance.

【table】

[Table] (Adhesion test) Acrylic rubber-chlorinated polyethylene blend rubber compounds (a) and (b) and a chlorinated polyethylene rubber compound having the formulations shown in Table 3 were prepared. A rubber compound (c) containing 100 parts of epichlorohydrin rubber, 40 parts of HAF carbon, 5 parts of magnesium oxide, 0.8 parts of trithiocyanuric acid, and 0.6 parts of diphenylguanidine was prepared as a rubber for these coatings. Each rubber compound was rolled out into sheets with a thickness of 2 mm, (a) and (b) were superimposed on (c), and the sheets were pressure vulcanized at 160° C. for 5 hours at 100 kg/cm ² . The test method (peel test) is JIS-
It was carried out according to K6301 and the results are shown in Table 3.

【table】

【table】 %
^*2 Rubber breakage (effect of the invention) The composition of the present invention does not impair the properties of chlorinated polyethylene by blending acrylic rubber copolymerized with chlorvinyl ether, which serves as a vulcanization point, with chlorinated polyethylene. Moreover, it is possible to obtain a vulcanizate which has significantly improved oil resistance at high temperatures and adhesion to different rubbers compared to single rubber. Therefore, it has great utility as a rubber laminate that can take advantage of the characteristics of each rubber, and has excellent adhesive strength with epichlorohydrin rubber, etc., so it is suitable for fields that require oil resistance, ozone resistance, heat resistance, etc.
For example, it can be effectively used in applications such as fuel hoses for engine parts.

[Brief explanation of drawings]

The drawing is a graph showing the vulcanization curves of Examples 1 and 2 and Comparative Examples 1 and 2.

Claims (1)

[Scope of Claims] 1 (a) The following polymer component)) 5 to 95 parts by weight of chlorinated polyethylene General formula as a copolymer component serving as a vulcanization point (In the formula, R ¹ represents a hydrogen atom or a C ₁ -C ₂ alkyl group, and R ² represents a hydrogen atom or a C ₁ -C ₃ alkyl group.) 95 to 5 parts by weight of acrylic rubber, (b) mercaptotriazines, (c) amines having a boiling point of about 110°C or higher, organic acid salts or adducts of the amines, diarylguanidines, condensation products of aniline and aldehydes, One or two selected from 2-benzothiazylsulfenamide of primary or secondary amines
A blend rubber composition characterized by containing at least one of the following compounds (a), (b), (c), and (d): (d) a metal compound serving as an acid acceptor;