WO1997016484A1 - RUBBER COMPOSITION COMPRISING HIGHLY SATURATED NITRILE COPOLYMER RUBBER AND ETHYLENE-α-OLEFIN COPOLYMER RUBBER - Google Patents

Abstract

A vulcanizable rubber composition comprising a highly saturated nitrile copolymer rubber prepared by hydrogenating the conjugated diene moieties of an unsaturated nitrile-conjugated diene-unsaturated dicarboxylic ester (preferably a dialkyl ester of an unsaturated dicarboxylic acid) copolymer, an ethylene-α-olefin copolymer rubber (preferably an ethylene-α-olefin-nonconjugated diene copolymer rubber), and an organic peroxide vulcanizing agent. The product of vulcanization of this composition exhibits excellent and well-balanced cold, oil and weathering resistances and is improved in heat resistance and compression set, so that it is useful for rubber-made parts which come into contact with various oils or gases and are required to be resistant to cold and oils.

Description

 Specification

Rubber composition comprising nitrile group-containing highly saturated copolymer rubber and ethylene-α-olefin copolymer rubber

 The present invention relates to a 'vulcanizable rubber composition comprising a nitrile group-containing highly saturated copolymer rubber and an ethylene-based saturated copolymer rubber. Background technology

 Some rubber compositions comprising a nitrile group-containing highly saturated copolymer rubber and an ethylene-based saturated copolymer rubber are known. For example, Japanese Unexamined Patent Publication (Kokai) No. Sho 61-2833639 discloses that the processability of ethylene-propylene rubber can be improved by blending hydrogenated acrylonitrile-butadiene copolymer rubber at a maximum of about 30% by weight. It is reported to be improved.

 Japanese Unexamined Patent Publication (Kokai) No. 61-43032 discloses a nitrile group-containing highly saturated copolymer obtained by hydrogenating a nitrile group-containing elastomer obtained by copolymerizing acrylic acid, alkyl acrylate and the like. It has been reported that a homogeneous co-vulcanizate obtained by vulcanizing a mixture of rubber and an ethylene-propylene copolymer rubber with an organic peroxide vulcanizing agent can be obtained.

 The applicant has disclosed in Japanese Patent Application Laid-Open No. 58-43032 an unsaturated nitrile monoconjugate obtained by copolymerizing an unsaturated carboxylic acid, an unsaturated carboxylic acid ester, or Ν-methylolacrylamide. Partial hydrogenation obtained by hydrogenating a gen-based copolymer rubber A mixture of an unsaturated nitrile-one conjugated gen-based copolymer rubber and an ethylene-propylene-non-conjugated terpolymer rubber is accelerated by a thiram system It was reported that vulcanization using a sulfur-based vulcanizing agent containing a dithiol-balvate-based vulcanizing agent can provide rubber materials with excellent oil resistance and the like.

 However, in recent years, rubber materials such as automotive parts have a balance of oil resistance, heat resistance, weather resistance, cold resistance, etc. in environments where they are used in a wide range from low to high temperatures.

Corrected form (Rule 91) In addition to being excellent, the compression set must not be particularly reduced, and further improvement has been desired. Disclosure of the invention

 An object of the present invention is to provide a rubber material having excellent balance such as oil resistance, heat resistance, weather resistance, and cold resistance and improved compression set.

 According to the present invention, a nitrile group-containing highly saturated copolymer rubber obtained by hydrogenating a conjugated gen moiety of an unsaturated nitrile conjugated gen-unsaturated dicarboxylic acid ester copolymer and an ethylene-α-olefin olefin There is provided a vulcanizable rubber composition comprising a copolymer rubber and an organic peroxide-based vulcanizing agent. BEST MODE FOR CARRYING OUT THE INVENTION

 The nitrile group-containing highly saturated copolymer rubber used in the present invention is obtained by hydrogenating the conjugated part of an unsaturated nitrile-conjugated di-unsaturated dicarboxylic acid ester copolymer. It has a knee viscosity of 15 to 200, preferably 30 to 100, and an iodine value of 80 or less, preferably 40 or less. If the Mooney viscosity is less than 15, only low strength molded products can be obtained. If the Mooney viscosity exceeds 200, the viscosity will increase and molding will be difficult. The lower limit for the iodine value is usually at least 1. If the iodine value is too low, vulcanization becomes difficult. If the iodine value is excessively high, heat resistance and weather resistance will decrease.

 Specific examples of the unsaturated nitrile include acrylonitrile, methacrylonitrile, α-chloroacrylonitrile and the like. Of these, acrylonitrile is preferred. The content of bound unsaturated nitrile units in the copolymer is from 10 to 40% by weight, and preferably from 15 to 30% by weight, based on the weight of the copolymer.

Specific examples of the conjugated diene include 1,3-butadiene, 2,3-dimethylbutane, isoprene, and 1,3-benzene. Among them, 1,3-butadiene is preferred. The content of bound conjugated gen units in the copolymer is usually from 10 to 70% by weight, preferably from 30 to 60% by weight, based on the weight of the copolymer. Oh "O o

Specific examples of the unsaturated dicarboxylic acid esters include monomethyl maleate, monoethyl maleate, monobutyrate maleate, mono-n-butyl maleate, monoisobutyl maleate, mono-n-maleic acid n-bentyl, and monomaleic acid. N-Hexyl, mono-2-maleylhexyl maleate, monomethyl fumarate, monoethyl fumarate, monobutamate fumarate, mono-n-butyl fumarate, monoisobutyl fumarate, mono-n-fumarate n-bentyl, fumarate Mono-n-hexyl acid, mono-2-ethyl fumarate, monomethyl itaconate, monoethyl itaconate, monopropyl itaconate, mono-n-butyl itaconate, mono-isobutyl itaconate, mono-n-bentyl itaconate, itacon Acid mono-n-hexyl, itako Mono-2-ethyl citrate, monomethyl citraconic acid, monoethyl citraconic acid, monobutyric acid citraconic acid, mono-n-butyl citraconic acid, monoisobutyl citraconic acid, mono-citraconic acid n-benchyl, mono-citraconic acid n- Hexyl, mono-2-ethyl citraconic acid, monomethyl mesaconic acid, monoethyl mesaconic acid, monobutacyl mesaconic acid, mono-n-butyl mesaconic acid, monoisobutyl mesaconic acid, monoisobutyl mesaconic acid n-bentyl, mono-mesaconic acid n-hexyl, mono-2-ethyl mesaconic acid hexyl, monomethyl glutaconate, monoethyl glutaconate, monopropyl glutaconate, mono-n-butyl glutaconate, monoisobutyl glutaconate, mono-glutaconate, mono-glutaconate n-bentyl, glutaco Mono-n-hexyl acid, mono-2-ethyl glutaconate, monomethyl arylmalonate, monoethyl arylmalonate, monobutyral malonate, mono-n-butyl arylmalonate, monoisobutyl arylmalonate, mono-n-arylmalonic acid -Pentyl, mono-n-hexyl arylmalonate, mono-2-ethylhexyl arylmalonate, monomethyl terraconate, monoethyl terraconate, monopropyl terraconate, mono-n-butyl terraconate, monoisobutyl terraconate, terraconate Mono-n-bentyl, mono-n-hexyl terraconate, mono-l-ethyl terraconate, monoalkyl unsaturated unsaturated dicarboxylates (e.g., 1 to 8 carbon atoms in the alkyl group) ) Esters;

 Furthermore, dimethyl maleate, getyl maleate, dibu mouth maleate, di-n-butyl maleate, diisobutyl maleate, di-n-pentyl maleate, di-n-hexyl maleate, di-n-hexyl maleate, di-n-hexyl maleate, 2-ethylhexyl, dimethyl fumarate, getyl fumarate, dibumouth fumarate, di-n-butyl fumarate, diisobutyl fumarate, di-n-bentyl fumarate, di-n-hexyl fumarate, di-n-hexyl fumarate, di-n-fumarate 2 —Ethylhexyl, dimethyl itaconate, getyl itaconate, dibu mouth itaconate, di-n-butyl itaconate, diisobutyl itaconate, di-itaconate n-bentyl, di-itaconate n-hexyl, itacon Diethyl hexyl acid, dimethyl citracone, getyl citrate, citracone Jib mouth building, di-n-butyl citraconic acid, diisobutyl citraconic acid, di-n-bentyl citraconic acid, di-n-hexyl citraconic acid, di-2-ethyl citraconic acid, dimethyl mesaconate, dimethyl mesaconate, mesacone Getyl acid, diprovir mesaconate, di-n-butyl mesaconate, diisobutyl mesaconate, di-n-bensyl mesaconate, di-n-hexyl mesaconate, di-l-ethylhexa mesaconate, glutaconic acid Dimethyl, getyl glutaconate, dibu glutaconate, di-n-butyl glutaconate, diisobutyl glutaconate, di-n-butyl glutaconate, n-bentyl glutaconate, n-hexyl glutaconate, di-ethylhexyl glutaconate, arylmalone Dimethyl acrylate, getyl arylmalonate, dibuarylmalonate Di-n-butyl arylmalonate, diisobutyl arylmalonate, di-n-bentyl arylmalonate, di-n-hexyl arylmalonate, di-2-ethylhexyl arylmalonate, dimethyl terraconate, dimethyl terraconate, getyl terraconate, terraconic acid Unsaturated dialkyl (alkyl) such as Jib mouth building, di-n-butyl terraconate, diisobutyl terraconate, di-n-pentyl terraconate, di-n-hexyl terraconate, di-2-ethyl terraconate, etc. The number of carbon atoms in the group is 1 to 8) Esters.

Among unsaturated dicarboxylic acid ester monomers, those having 4 to 6 carbon atoms An ester of a saturated dicarboxylic acid, which is an unsaturated dicarboxylic acid dialkyl ester having an alkyl group having 1 to 5 carbon atoms, preferably 2 to 4 carbon atoms, is suitable. The content of the unsaturated dicarboxylic acid ester monomer unit is usually 1 to 80% by weight, preferably 15 to 60% by weight, more preferably 20 to 40% by weight based on the weight of the copolymer. Range. By copolymerizing such amount of unsaturated dicarboxylic acid ester monomer with unsaturated nitrile and conjugated diene, the oil resistance, heat resistance, weather resistance, and cold resistance of the nitrile group-containing highly saturated copolymer rubber can be improved. The balance of properties can be improved. If the amount of the unsaturated dicarboxylic acid ester is too small, a nitrile group-containing highly saturated copolymer rubber having a good balance of oil resistance, heat resistance, weather resistance and cold resistance cannot be obtained. Conversely, if the amount is too large, the oil resistance decreases.

 If desired, other copolymerizable monomers can be used in addition to the above-mentioned monomers as long as the effects obtained by the present invention are not impaired. Other copolymerizable monomers include vinyl monomers such as styrene, α-methylstyrene and vinyl pyridine; non-conjugated monomers such as vinyl norbornene, dicyclopentane and 1,4-hexadiene. Fluoroalkyl such as fluoroethyl vinyl ether, fluorovyl vinyl ether, trifluoromethyl vinyl ether, trifluoroethyl vinyl ether, bar fluororubil vinyl ether, and fluoroxyhexyl vinyl ether Fluorine-containing vinyl monomers such as vinyl ether, ο- or Ρ-trifluoromethylstyrene, vinyl pentafluorobenzoate, difluoroethylene, tetrafluoroethylene; and polyethylene glycol (meth) acrylate, polypropylene glycolMeth) Akuri rate, epoxy (meth) Akuri rate, such as urethane (meth) Akurireto the like.

To methyl acrylate, ethyl acrylate, proville acrylate, η-butyl acrylate, t-butyl acrylate, isobutyl acrylate, n-pentyl acrylate, isononyl acrylate, n- Xylacrylate, 2-methyl-bentylacrylate, n-octylacrylate, 2- Acrylates and methacrylates having an alkyl group having about 1 to 18 carbon atoms, such as ethylhexyl acrylate, n-dodecyl acrylate, methyl methacrylate, and ethyl methacrylate;

 Methoxymethyl acrylate, methoxyl acrylate, ethoxyxyl acrylate, butoxyshethyl acrylate, ethoxypropyl acrylate, methoxyxyl acrylate, ethoxybutoxy acrylate Acrylates having an alkoxyalkyl group having about 2 to 12 carbon atoms, such as acrylates;

 α and / S—Canoethyl acrylate, α, and τ-Cyanobue acrylate, Canobutyl acrylate, Canohexyl acrylate, Canooctyl acrylate, etc. 2 carbon atoms An acrylate having about 12 cyanoalkyl groups;

 2-acrylates having a hydroxyalkyl group, such as hydroxyethyl acrylate and hydroxybile acrylate; dimethylaminomethyl acrylate, getylaminoethyl acrylate; 3— Unsaturated monocarboxylic acid ester monomers such as (ethylethylamino) 12—hydroxyl mouth acrylate and 2,3-bis (difluoroamino) broacrylate

Trifluoroethyl acrylate, Tetrafluorov mouth acrylate, Bentafololov mouth acrylate, Hebutafluorobutyl acrylate, Oktafluoropentyl acrylate, Nonafoloventilate acrylate Hexyl acrylate, pentadecafluor octyl acrylate, nonadecafluor nonyl acrylate, hebutadecafluoro decyl acrylate, nonadecafluor decyl acrylate, trifluorofluorethyl methacrylate, tetrafluroyl Mouth building methacrylate, octafluo vent butyl methacrylate, dodecafluo butyl methacrylate, pen decafluoro octyl octyl acrylate, hexadecafluorononyl methacrylate, etc. Acrylates and methacrylates having a fluoroalkyl group: and fluorine-substituted benzyl acrylates such as fluorene benzyl acrylate, fluorobenzyl methacrylate, difluorobenzyl methacrylate and the like. Me Unsaturated monocarboxylic acid ester monomers such as tacrylate can also be copolymerized.

 The amount of the copolymerizable monomer used is usually 10% by weight or less, preferably 5% by weight or less, based on the total weight of all monomers.

 The method of hydrogenating the unsaturated nitrile conjugated gen-unsaturated dicarboxylic acid ester copolymer is not particularly limited, and the hydrogenation can be performed according to a conventional method. Examples of the catalyst used in the hydrogenation include palladium Z silica and a palladium complex (JP-A-3-252405). Furthermore, JP-A-62-125858, JP-A-6-42939, JP-A-1-45402, JP-A-145504 And rhodium or ruthenium compounds as described in JP-A No. 1-44504, JP-A No. 1-45405 and the like can also be used.

 The nitrile group-containing highly saturated copolymer rubber used in the present invention can also be obtained by a method of directly hydrogenating a latex of an unsaturated nitrile-conjugated di-unsaturated carboxylic acid ester copolymer. Examples of the method for direct hydrogenation include a method using a palladium catalyst (for example, JP-A-2-178305), a method using a rhodium-based catalyst (for example, JP-A-59-1111). No. 5303, JP-A-56-133209, U.S. Pat. No. 3,988,208), and a method using a ruthenium-based catalyst (for example, No. 1,842,23, JP-A-6-192,233), and the like, but are not limited thereto. As a specific example, for example, when a palladium catalyst is used, the nitrile group-containing unsaturated copolymer is dissolved or swelled as described in JP-A-2-178305. The organic solvent to be added is added to the copolymer latex. According to this method, the nitrile group-containing unsaturated copolymer in the copolymer latex swells with the organic solvent, and the hydrogenation catalyst can be easily approached to the double bond in the copolymer. However, the hydrogenation reaction can be efficiently performed while maintaining the aqueous emulsion state.

Specific examples of the palladium compound include, for example, formic acid, acetic acid, propionic acid, Palladium salts of carboxylic acids such as lauric acid, succinic acid, stearic acid, oleic acid, phthalic acid, and benzoic acid; palladium chloride, dichloro (cyclooctadiene) palladium, dichloro (norbornadiene) palladium, dichloro (benzonitrile) Chlorinated products of palladium, such as radium, dichlorobis (triphenylphosphine) palladium, ammonium tetrachloride palladium (II) acid, and hexachloropalladium (IV) ammonium palladium; palladium bromide; palladium iodide Complex salts of inorganic compounds such as potassium, valadium sulfate, dihydrate; potassium tetracyanopalladium (II) acid salt, trihydrate; and the like, but are not limited thereto. Among them, palladium salts of carboxylic acids, dichloro (norbornadiene) palladium, ammonium palladium ammonium palladate and the like are particularly preferred.

 The ethylene-α-olefin copolymer rubber used in the present invention is a copolymer of ethylene and α-olefin or a copolymer of ethylene, α-olefin and non-conjugated gen. A substantially saturated binary, ternary or higher multi-component copolymer rubber. Typical examples are ethylene-propylene-non-conjugated gen terpolymer rubber, ethylene-brovirene-1butene-non-conjugated quaternary copolymer rubber, ethylene / 1-butene-non-conjugated gen ternary or multi-component copolymer rubber. Ternary or higher multi-component copolymer rubbers containing ethylene and α-olefin having 3 to 14 carbon atoms as main components, such as polymer rubber. The copolymer rubber is usually a low-crystalline or amorphous elastomer having a crystallinity of 20% or less, more preferably 10% or less, or a mixture thereof. Among them, ethylene-propylene-non-conjugated gen terpolymer rubber is preferred.

 Here, as the non-conjugated diene, dicyclopentane, 1,4-hexadiene, cyclooctadiene, methylidene norbornene, 5-ethylidene-2-norbornene and the like are used. Of these, dicyclopentadiene And 5-ethylidene-12-norbornene are preferred.

The Mooney viscosity [Μ1 _{+ 4} (100 ° C.)] of the ethylene-α-olefin refin-based copolymer rubber is usually from 10 to 180, preferably from 40 to: L 4 0, and Its iodine unsaturation is preferably 20 or less.

 In these ethylene-α-olefin copolymer rubbers, the ratio of ethylene unit to olefin unit is 50Ζ50 to 90Ζ10, preferably 60 40 to 84/16 (molar ratio). In the case of terpolymers or higher copolymers containing gen units, (ethylene + α-olefin) units Non-co-functional gen units are usually 98Ζ2-90Ζ10, preferably 97Ζ3-94Ζ6 (molar ratio) .

 The mixing ratio of the nitrile group-containing highly saturated copolymer rubber and the ethylene-α-olefin copolymer rubber is usually 95 to 20% by weight, preferably the nitrile group-containing highly saturated copolymer rubber. 70 to 50% by weight, and ethylene to α-olefin copolymer rubber 5 to 80% by weight, preferably 30 to 50% by weight. If the relative proportion of the nitrile group-containing highly saturated copolymer rubber is excessively large, the weather resistance is reduced, and if the relative proportion of the ethylene-α-olefin copolymer rubber is excessively large, the oil resistance is reduced. Decrease.

 The method for blending the nitrile group-containing highly saturated copolymer rubber and the ethylene-α-olefin copolymer rubber is not particularly limited, but usually, the nitrile group-containing highly saturated copolymer rubber and ethylene- Dry blending method in which α-blended copolymer rubber is mixed at a high temperature using a Banbury mixer, etc., or nitrile-containing highly saturated copolymer rubber and ethylene-α-blended copolymer A latex coprecipitation method is used in which the combined rubber is mixed in a latex state, coagulated and dried, and then heat-treated using an extruder or Banbury mixer.

The organic peroxide-based vulcanizing agent used in the present invention is not particularly limited as long as it is one used in ordinary peroxide vulcanization of rubber. Examples include dicumyl peroxide, g-tert-butyl peroxide, t-butylcumyl peroxide, benzoyl peroxide, 2,5-dimethyl-1,2,5-dihexylhexyl Examples include 1,3,2,5-dimethyl-2,5-di (benzoylpropoxy) hexine, a, a'-bis (t-butylperoxy-1m-ibbguchi) benzene and the like. Above all, G-t-butyl alcohol Is preferred. These organic peroxides are used in an amount of 0.1 to 15 parts by weight based on 100 parts by weight of the copolymer rubber.

 Further, examples of the crosslinking aid include unsaturated compounds used in ordinary organic peroxide vulcanization. Specific examples thereof include ethylene glycol dimethacrylate, trimethylolpropane remethacrylate, polyfunctional methyl methacrylate monomer, N, Ν'-m-phenylenediimide, triaryl isocyanate Nurate and the like. Of these, triallyl isocyanurate is preferred from the viewpoint of vulcanization properties. These addition amounts are in the range of 0.1 to 15 parts by weight based on 100 parts by weight of the copolymer rubber.

 In the present invention, it is necessary to use an organic peroxide-based vulcanizing agent as the vulcanizing agent. When a sulfur-based vulcanizing agent other than the organic peroxide-based vulcanizing agent is used, for example, it becomes difficult to obtain a rubber material having particularly excellent compression set resistance.

If necessary, the vulcanizable rubber composition of the present invention may further contain other compounding agents used in the rubber field, such as reinforcing agents (various carbon black, silica, talc, etc.), agent (calcium carbonate, clay, etc.), processing aids, processing oils (including plasticizer), antioxidants, the vulcanizable rubber composition of _c it should be noted that the present invention can be blended with ozone裂化inhibitor, If necessary, use a combination of other rubbers such as acrylic rubber, fluorine rubber, acrylonitrile-butadiene rubber, styrene-butadiene copolymer rubber, natural rubber, polyisobrene rubber, and ethylene-vinyl acetate copolymer resin. can do.

 The method for producing the vulcanizable rubber composition of the present invention is not particularly limited, but usually, the raw material copolymer rubber and the vulcanization system and other compounding agents are mixed by a mixer such as a mouth or a Banbury mixer. To produce the rubber composition.

 Hereinafter, the present invention will be described more specifically with reference to examples. Parts and percentages in the examples, comparative examples and reference examples are based on weight unless otherwise specified.

 The characteristics of the rubber composition and the raw material components were measured as follows.

 (1) Vulcanization property evaluation test

According to Japanese Industrial Standard JISK 6301, prepared according to the formulation shown in Table 1. A 2 mm thick sheet obtained by vulcanizing the unvulcanized rubber composition at 170 ° C for 30 minutes was punched out using a No. 3 type bender to prepare a test piece, and the tensile strength ( Unit: kgf Z cm2), 100% tensile stress (unit: kgf / cm2) and elongation (unit:%) were measured. The hardness was measured using a JIS spring type A hardness tester. Further, the compression set was measured in accordance with JIS K6301 when the sample was kept at 150 at 77 hours and when it was kept at 120 at 8 hours (unit:%).

 (2) Oil resistance test

 According to JIS K6301, the rubber test piece was immersed in lubricating oil No. 3 (150, 72 hours), and the volume change rate (unit:%) was measured.

 (3) Cold resistance test

 According to JIS K6301, evaluation was made by the Gehman torsion test. When the torsion angle is low (23 ° C), the temperature (TR10) at which the torsion angle becomes 10 times the torsion angle is shown (unit: te). The lower the temperature, the better the cold resistance.

 (4) Ozone resistance (weather resistance)

 According to JIS K6301, the ozone concentration is 50 ppm and the temperature is 40. After elongating statically at 20% in C, and then allowed to stand for 12, 24, 48 and 72 hours, the state of crack generation was observed. In Tables 7 to 11, “NC” indicates that no cracks were found.

Room examples 1 to 16, H-1 to: L6

 A nitrile group-containing highly saturated copolymer rubber (HN BR 1-4, 8-11) having an unsaturated dicarboxylic acid ester unit shown in Tables 1-2 and ethylene-like one-year-old olefin copolymer rubber (EP DM1, 2) were mixed in the proportions (% by weight) shown in Tables 3 and 4, and an evaluation test was performed on a vulcanizable rubber composition containing an organic peroxide vulcanizing agent. Show results? ~ 10.

For comparison, a nitrile group-containing highly saturated copolymer rubber having an unsaturated monocarboxylic acid ester unit (HNBR 5, 6, 12, 12, 13) and an ethylene-α-olefin copolymer rubber (E PDM 1 , 2), and vulcanizable rubber composition An evaluation test was performed for (Comparative Examples 1, 2, 7, and 8), and the results are shown in Tables 7 and 9.

 HN BRs 7 and 14 are highly saturated copolymer rubbers containing no unsaturated carboxylic acid ester units, obtained by hydrogenating a binary copolymer of acrylonitrile and bushugen. Evaluation tests were performed on these in the same manner as described above (Comparative Examples 3, 4, 6, 9, 10, and 12), and the results are shown in Tables 8 and 10.

 In addition, a similar evaluation test was conducted for a rubber composition using only an ethylene-α-vinyl olefin copolymer rubber (EPDM1) without using a nitrile group-containing highly saturated copolymer rubber (HNBR). (Comparative Examples 5 and 11), and the results are shown in Tables 8 and 10.

 The formulation of the vulcanizable rubber composition (Examples 1 to 6, Comparative Examples 1 to 12) is as follows.

 Copolymer rubber mixture 00 parts FT carbon black 60 parts

1 S A F carbon black 50 parts trimellitate plasticizer 30 parts

2-Zinc salt of mercaptan benzone midazole .5 parts Substituted difuunylamine .5 parts

1,3-Bis (tert-butylperoxyisopropyl) benzene 8 parts The following ethylene-α-olefin copolymer rubber was used.

 (1) Ethylene-propylene dicycloventene copolymer (hereinafter referred to as EP Ml)

 Ethylene Z-brovilene Z-dicycloben-yen = 55/40/5 (molar ratio) Muney viscosity 80

 (2) Ethylene-propylene-ethylidene norbornene copolymer (hereinafter referred to as EPDM2)

Styrene propylene / 5-ethylidene-2-norbornene = 60 Z 35/5 (molar ratio) Mooney viscosity 8 5

 Eclectic 1-trility; rubber (1)

2 2 = ■ ¾ ¾ ¾ ¾ ¾ ¾ ¾ ゴ ム 2 ¾ ¾ ¾ ¾ ¾ ¾ ¾ ¾ 2 HNBR8 HNBR 9 HNBR10 HNBB11 HNBR 12 HNBR13 HNBR14 Bond “Li nitrite * Amount” 31 30 32 31 30 33 36 Unsaturated

 Maleic acid 24

 Citra] acid! / 'Etil 26

 Itaconic acid 25

 Itaic acid; / '-n-phthyl 26

 n-Fuyl tylarylate 27

2-Ethyl Λ 7 'ソ ル 24 24 24 ゥ 11 10 11 10 10 11 10 11 一 粘度 82 80 81 79 85 80 85 & _ 2. Rubber F. A th (1

¾ 4_ rubber ratio f 2)

 Example Comparative example

6 7 8 3 4 5 6

H N B R 1

 H N B R 2

 H N B R 3 50

 H N B R 4 50 50

 H N B R 5

 H N B R 6

 H N B R 7 70 100 5 0

E P D M 1 50 50 30 100 5 0

EPDM 2 50 _ 5. Rubber distribution (3) Example Comparative example

9 1 0 1 1 1 2 1 3 7 8

H N B R 8 70

 H N B R 9 70

 H N B R 10 70

 H N B R 11 70 70

 H N B R 12 70

H N B R 13 70

E P D 1 30 30 30 30 30 30

E P D M 2 30

_ L · rubber (^ Comparative example

 1 4 1 5 1 6 9 1 0 1 1 1 2

H N B R 8

 H N B R 9

 H N B R 10 50

 H N B R 11 50 50

 H N B R 12

 H N B R 13

 H N B R 14 70 100 '50

E P D M 1 50 50 30 100 50

EPD 2 50 Table 7 Cases of rubber S (ΐ

 Example Example Comparative Example

1 2 3 4 5 1 2 Vulcanization property evaluation test

Tensile strength _{(kgf / c n 2) 201} 197 189 199 196 179 168 elongation (X) 170 180 180 180 180 160 160

100 1 Tensile stress (kgf / cia ² ) 95 89 88 90 92 77 79 Hardness (J IS-A) 72 70 71 71 72 68 69 Compression set (X) 150 * C 12 13 13 12 13 15 15

 -20 ° C 29 29 28 28 29 33 35 Oil resistance test

 Volume change rate (¾) +41 +42 +40 + 1 +41 +45 +44 Cold resistance test

 TRI O CO -33 -34 -33 -36 -35 -29 -28

¾ v sex test

 12 hours NC NC NC NC NC NC NC NC

24 hours NC NC NC NC NC NC NC

48 hours NC NC NC NC NC NC NC

72 hours NC NC NC NC NC NC NC

¾_JL Properties of rubber vulcanizates (2) Examples Comparative examples

6 7 8 3 4 5 6

TIP 任 Responsible plate β »ϋ narrow

Tensile strength (kgf / ce ² ) 164 170 168 212 245 123 185 Elongation (X) 160 160 160 200 220 150 180 no

100X515κ (kgf / cm 95 98 DO d c iO Hardness (JIS-A) 72 71 72 71 70 72 71 Compression permanent 150 C 11 10 10 10 14 12 12

 -20 ° C 25 24 24 43 5b 21 32 Oil resistance test

 Volume change rate (X) + 50 + 51 + 51 + 35 + 21 + 82 + 61 Cold resistance test

 TRIO CC) -34 -37 -34 -27 -25-50 -29

 12 hours NC NC NC NC NC NC NC NC

24 hours NC NC NC NC NC NC NC

48 hours NC NC NC NC NC NC NC

72 hours NC NC NC NC NC NC NC

Table 9 # of rubber additives (Example Comparative Example

9 1 0 1 1 1 2 1 3 Vulcanization property evaluation test

Tensile strength (kgf / cm ² ) 222 218 224 229 231 i ゥ ll ゥ 205 Elongation (X) 190 200 200 210 200 19u 180

100X tensile stress (kgf / cm ² ) 84 82 81 81 80

 W (J is-A) 72 73 72 72 73 71 70 Compression set (X) 150 "C 15 16 15 15 14 17 18

 34 37 40 40 Oil resistance test

 Volume change rate (X) + 30 + 32 + 30 + 31 + 31 + 36 + 37 Cold resistance test

 TRIO CC) -30 -30 -30 -31 -31 -27 -26

«Ί '' / Sex test

 12 hours NC NC NC NC NC NC NC NC

24 hours NC NC NC NC NC NC NC

48 hours NC NC NC NC NC NC NC

72 hours NC NC NC NC NC NC NC

Table 1 Characteristics of Q rubber vulcanizates # (4

また、 比較として、 実施例 4、 7、 11および 14と同じ HNBRと EPD Mとの混合組成について、 有機過酸化物に代えて硫黄系加硫剤を配合した他は 実施例と同様な方法により評価試験を行った。 その配合処方 （比較例 1 3〜1 6) は以下のとおりである。 結果を表 11に示した。

For comparison, the same mixture composition of HNBR and EPDM as in Examples 4, 7, 11, and 14 was used in the same manner as in Example except that a sulfur-based vulcanizing agent was used instead of the organic peroxide. An evaluation test was performed. The formulation (Comparative Examples 13 to 16) is as follows. The results are shown in Table 11.

 100 parts of copolymer rubber mixture

FT carbon black 60 parts

I SAF carbon black 50 parts Trimellitic acid ester plasticizer 30 parts

2 Zinc salt of mercaptobenzimidazole 1.5 parts Zinc flower 5 parts Stearate 1 part Sulfur 0.5 part 20 Tetramethylthiuram disulfide 1.5 parts

0.5 part of 2-mercaptobenzothiazole Table 1 I Special stirring of sulfurized rubber

 From the results of Tables 7 to 11, the vulcanizate obtained by vulcanizing the rubber composition of the present invention has lower cold resistance and oil resistance than the copolymer rubber having an unsaturated monocarboxylic acid ester unit. It is understood that the heat resistance and the compression set are improved while the weather resistance is well balanced.

In particular, from the results of Tables 7 and 9, it is clear from the experimental examples (Examples 1 to 5) that the unsaturated dicarboxylic acid dialkyl ester-based monomer was used as the nitrile group-containing highly saturated copolymer rubber. , 9 to 13), examples using copolymers of unsaturated dicarboxylic acid monoalkyl ester monomers (Comparative Examples 1, 2, 7, 8) The tensile strength and the 100% tensile stress are increased, and the compression set and cold resistance (TR 10) at low temperature (120 ° C) are shown to be better than those of o.

 Furthermore, from Table 11, when a sulfur-based vulcanizing agent was added instead of the organic peroxide in the rubber compositions of Examples 4, 7, 12, and 15, the tensile stress was reduced by 100%, Also, it can be seen that the compression set resistance (150) is insufficient. Industrial applications

 The vulcanized product obtained by vulcanizing the rubber composition of the present invention has an excellent balance of cold resistance, oil resistance, and weather resistance, and has improved heat resistance and compression set. It is effective when used for rubber parts that require cold and oil resistance.

 Accordingly, the vulcanizable rubber composition of the present invention can be used for various sealing rubber products such as O-rings, packings, gaskets, etc .; various belts such as conveyor belts, V-belts, timing belts; BOP (blow-out preventer), bladders, etc .; various cushioning materials, vibration-proof materials, etc .; can be widely used in the production of various hoses such as oil hoses, marine hoses, risers, flow lines, etc. .

Claims

The scope of the claims  1. A nitrile group-containing highly saturated copolymer rubber obtained by hydrogenating a conjugated gen moiety of an unsaturated nitrile conjugated gen-unsaturated dicarboxylic acid ester copolymer, an ethylene-α-methyl olefin copolymer rubber and A vulcanizable rubber composition containing an organic peroxide-based vulcanizing agent.  2. 100 parts by weight of a rubber mixture comprising 95 to 20% by weight of nitrile group-containing highly saturated copolymer rubber and 5 to 80% by weight of ethylene-α-olefin copolymer rubber 2. The vulcanizable rubber composition according to claim 1, comprising 0.1 to 15 parts by weight of an organic peroxide vulcanizing agent.  3. The vulcanizable rubber composition according to claim 1, wherein the unsaturated nitril is selected from acrylonitrile, methacrylonitrile and α-chloroacrylonitrile.  4. The method according to any one of claims 1 to 3, wherein the conjugated diene is selected from 1,3-butadiene, 2,3-dimethylbutadiene, isoprene and 1,3-pentadiene. Vulcanizable rubber composition.  5. The vulcanizable rubber composition according to any one of claims 1 to 4, wherein the unsaturated dicarboxylic acid ester is an unsaturated dicarboxylic acid dialkyl ester.  6. The nitrile group-containing highly saturated copolymer rubber is composed of 10 to 40% by weight of unsaturated nitrile units, 10 to 70% by weight of conjugated units and 1 to 80% by weight of unsaturated dicarboxylic acid ester units. The vulcanizable rubber composition according to any one of claims 1 to 5, wherein 7. Unsaturated nitrile is acrylonitrile, conjugated diene is 1, 3-blanking evening vulcanizable rubber composition according to any one of claims first term to sixth term is Jen ₍ 8. The process according to any one of claims 1 to 7, wherein the nitrile group-containing highly saturated copolymer rubber has an iodine value of 80 or less and a viscosity of 15 to 200. Vulcanizable rubber composition. 9. The ethylene-α-olefin copolymer rubber is a copolymer of ethylene, α-olefin and non-conjugated gen, and is a substantially saturated copolymer rubber. The vulcanizable rubber composition according to any one of claims 1 to 8, wherein:  10. Ethylene-α-olefin copolymer rubber is low-crystalline or non-crystalline with a crystallinity of 20% or less, mainly composed of ethylene and α-olefin having 3 to 14 carbon atoms. The vulcanizable rubber composition according to any one of claims 1 to 9, which is an elastomer or a mixture thereof.  1 1. Ethylene-α-olefin copolymer rubber is composed of ethylene-propylene-non-conjugated diene copolymer rubber, ethylene-propylene-1-1-butene-non-conjugated diene copolymer rubber and ethylene-1-butene. The vulcanizable rubber composition according to any one of claims 1 to 10, wherein the vulcanizable rubber composition is selected from among non-conjugated gen copolymer rubbers.  1 2. Ethylene mono-alpha-olefin-non-conjugated gen-copolymer rubber non-conjugated gen < The vulcanizable rubber composition according to claim 11, which is selected from 2-norbornene.  1 3. The viscosity of ethylene-α-olefin copolymer rubber [M Li 10 4 (100 ° C)] The vulcanizable rubber composition according to any one of claims 1 to 12, wherein the iodine value is 10 to 180, and the iodine value is 20 or less.  1 4. Claims wherein the ethylene-α-age olefin copolymer rubber has an ethylene unit-α-age refine unit copolymerization ratio in the range of 5Ο / δΟθθΖΐΖΐ (molar ratio). 14. The vulcanizable rubber composition according to any one of Items 1 to 13.  1 5. In ethylene-α-olefin-non-conjugated gen copolymer rubber, the copolymerization ratio of (ethylene + α-olefin-refin) units Ζ non-conjugated gen units is 98 / 2-9 0/1 0 ( The vulcanizable rubber composition according to any one of claims 11 to 14, wherein the composition has a molar ratio of: