Abstract: A rubber composition is provided, which comprises: (1) 100 parts by mass of a hydrogenated acrylonitrile-butadiene copolymer rubber having high rate of hydrogenation; (2) 1 to 10 parts by mass of an organic peroxide; (3) 0.1 to 15 parts by mass of 2,4-dimercapto-6-substituted-1,3,5-triazine; and (4) 1 to 100 parts by mass of an organic peroxide-crosslinkable polymer having an epoxy group. The rubber composition has high adhesiveness to a metal, high modulus, high set resistance and high heat resistance, thereby being capable of suitably utilizing for composites of rubber and metal, such as belts, tires, rolls, and molded goods, particularly, for composite rubber products of the rubber composition and a brass or bronze-plated steel plate.

Abstract: A laminate of vulcanizable rubber composition layers, which comprises (i) a vulcanizable fluororubber composition layer comprising a fluororubber and a metal oxide and (ii) a vulcanizable nitrile rubber composition layer consisting essentially of a nitrile rubber, an organic phosphonium salt of the following formula (1), an organic peroxide crosslinking system, and an organic basic vulcanization accelerator: ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are hydrocarbyl, and no more than three thereof may be amino or fluoroalkyl; and R.sub.5 is hydrogen or alkyl. A vulcanized laminate made of the vulcanizable rubber composition layers is useful for a fuel hose or a diaphragm.

Abstract: A composite comprised of a nitrile group-containing highly saturated copolymer rubber and a fibrous material, which copolymer rubber is a product obtained by hydrogenating the conjugated diene portion of an unsaturated nitrile-conjugated diene copolymer. The highly saturated copolymer rubber has an alkylthio group having 12 to 16 carbon atoms, which include at least three tertiary carbon atoms, and having a sulfur atom which is directly bound to at least one of the tertiary carbon atoms; and the copolymer rubber further has a Mooney viscosity of 15 to 200 and an iodine value not larger than 80. This composite is useful for a belt.

Abstract: A nitrile group-containing highly saturated copolymer rubber which is a product obtained by hydrogenating the conjugated diene portion of an unsaturated nitrile-conjugated diene copolymer. The highly saturated copolymer rubber has an alkylthio group having 12 to 16 carbon atoms, which include at least three tertiary carbon atoms, and having a sulfur atom which is directly bound to at least one of the tertiary carbon atom, and the highly saturated copolymer rubber further has a Mooney viscosity of 15 to 200 and an iodine value not larger than 80. The highly saturated copolymer rubber is produced copolymerizing an unsaturated nitrile, a conjugated diene and an optional copolymerizable monomer by using as a molecular weight modifier an alkylthiol compound having 12 to 16 carbon atoms, which include at least three tertiary carbon atoms, and having a sulfur atom which is directly bound to at least one of the tertiary carbon atoms; and then, hydrogenating the thus-obtained copolymer.

Abstract: A vulcanizable rubber composition including a partially hydrogenated unsaturated nitrile-conjugated diene copolymer having an iodine value of smaller than 25, a sulfur vulcanizer and a tellurium dithiocarbamate compound as a vulcanization promotor. This rubber composition provides a vulcanizate having reduced heat build-up, reduced compression set and high mechanical strength.

Abstract: A rubber composition comprising (i) a nitrile group-containing highly saturated copolymer rubber, which is a product obtained by hydrogenating the conjugated diene portion of an unsaturated nitrile-conjugated diene copolymer, and (ii) an ethylene-.alpha.-olefin-non-conjugated diene copolymer rubber. The highly saturated copolymer rubber has an alkylthio group having 12 to 16 carbon atoms, which include at least three tertiary carbon atoms, and has a sulfur atom which is directly bound to at least one of the tertiary carbon atoms; and the highly saturated copolymer. rubber further has a Mooney viscosity of 15 to 200 and an iodine value not larger than 80.

Abstract: Disclosed herein is a rubber covered roll comprising a metallic core and at least one covering rubber layer. The covering rubber layer is a vulcanized rubber layer formed by a rubber composition comprising an ethylenically unsaturated nitrile-conjugated diene type highly saturated copolymer rubber (A) having a conjugated diene unit content of the polymer chain of at most 25 wt. % and the zinc salt (B) of an ethylenically unsaturated carboxylic acid. A covering rubber layer coming into contact with the metallic core is at least a vulcanized rubber layer formed by a rubber composition comprising 100 parts by weight of a rubber component containing at least 50 wt. % of the highly saturated copolymer rubber (A) and 10-40 parts by weight of the zinc salt (B). A rubber composition for rubber covered rolls is also disclosed. It comprises 100 parts by weight of a rubber component containing 90-50 wt. % of the highly saturated copolymer rubber (A) and 50-10 wt.

Abstract: A nitrile group-containing rubber latex comprising an aqueous dispersion of a nitrile group-containing highly saturated rubber having an iodine value of not more than 120. The said rubber latex can be produced by converting a solution of a nitrile group-containing highly saturated polymer rubber having an iodine value of not more than 120 in an inert solvent into an oil-in-water emulsion using water and an emulsifier, and removing the solvent from the resulting emulsion.

Abstract: A process for producing a fiber-rubber composite comprising:a polyester fiber treated with (1) an adhesive composition (AR) consisting mainly of a latex (A) of a vinylpyridine-conjugated diene type copolymer containing a vinylpyridine unit in an amount of not less than 20% by weight but not more than 70% by weight and a resorcinol-formaldehyde resin and then with (2) an adhesive composition (BR) consisting mainly of a latex (B) of a nitrile group-containing highly saturated copolymer rubber having an iodine value of 120 or less obtained by emulsion polymerization or by emulsion polymerization followed by hydrogenation in the emulsion state and a resorcinol-formaldehyde resin, anda nitrile group-containing highly saturated copolymer rubber having an iodine value of 20 or less, which process comprises bonding said polyester filber and said nitrile group-containing highly saturated copolymer rubber having an iodine value of 20 or less, by vulcanizing by a peroxide vulcanizing system.

Abstract: An adhesive composition for adhering an organic synthetic fiber to a nitrile group-containing highly saturated copolymer rubber, said composition comprising a nitrile group-containing highly saturated copolymer rubber latex having an iodine value of not more than 120 and a resorcinol-formaldehyde resin, characterized in that the nitrile group-containing highly saturated copolymer rubber latex is obtained by treating a nitrile group-containing unsaturated copolymer rubber latex resulting from emulsion polymerization with hydrogen in the presence of a hydrogenation catalyst to selectively hydrogenate a carbon-carbon double bond of the nitrile group-containing unsaturated copolymer constituting said latex.

Abstract: A method of treating polyester fibers, which comprises(1) treating the polyester fibers with an adhesive composition (AR) comprising a latex (A) of a vinylpyridine/conjugated diene copolymer having a vinylpyridine unit content of at least 20% by weight but not more than 70% by weight and a resorcinol-formaldehyde resin as main components, and(2) further treating it with an adhesive composition (BR) comprising a latex (B) of a ntirile group-containing highly saturated copolymer rubber having an iodine number of not more than 120 and a resorcinol-formaldehyde resin as main components. A composite obtained by bonding the treated polyester fibers to a nitrile group-containing highly saturated copolymer rubber by vulcanization has high initial and heat-resistant adhesion strength, and is useful for production of timing belts and polyribbed belts.

Abstract: An adhesive for bonding a nitrile group-containing highly saturated rubber to glass fibers or organic synthetic fibers, which comprises a nitrile group-containing highly saturated rubber latex having an iodine number of not more than 120 and a resoncinol/formaldehyde resin.

Abstract: In a method for bonding a nitrile group-containing highly saturated polymer rubber having an iodine value of 120 or less to fibers on vulcanization, the improvement wherein fibers treated with an aqueous dispersion comprising a halogen-containing polymer latex and a resorcinol-formaldehyde resin are used.

Abstract: An adhesive for bonding a nitrile group-containing highly saturated rubber to glass fibers or organic synthetic fibers, which comprises a nitrile group-containing highly saturated rubber latex having an iodine number of not more than 120 and a resorcinol-formaldehyde resin.

Abstract: A rubber composition capable of giving a vulcanizate having improved ozone resistance. The composition comprises a nitrile group-containing highly saturated polymer rubber having an iodine value of not more than 80, an organic peroxide, a crosslinking coagent and a quinoline-type stabilizer.

Abstract: An anti-degrading rubber article to be used in contact with a mineral oil containing an oil modifier, at least that surface of said rubber article which is to come into contact with said mineral oil being composed substantially of a vulcanization product, obtained by using a sulfur vulcanization system, of a copolymer rubber having polymer chains consisting of(1) 10 to 60% by weight of units derived from an unsaturated nitride,(2) 2 to 30% by weight of units derived from a conjugated diene, and(3) 88 to 10% by weight of units derived from a copolymerizable ethylenically unsaturated monomer other than the unsaturated nitride and/or units resulting from the hydrogenation of units derived from a conjugated diene.

Abstract: A rubber article with excellent oil resistance and aging resistance to be used in contact with a polyolefin oil or a lubricating oil containing a polyolefin oil, at least the surface of the rubber article being contacted with said oil, said rubber article being composed substantially of a vulcanized product of a copolymer rubber comprising (1) 10 to 60% by weight of units derived from an unsaturated nitrile, (2) 0 to 30% by weight of units derived from a conjugated diene, and (3) 90 to 10% by weight of units derived from an ethylenically unsaturated monomer other than the unsaturated nitrile and/or units resulting from the hydrogenation of units derived from a conjugated diene.

Abstract: A belt comprising a copolymer rubber and fibers and having strong adhesion strength even after heat-aging in air or oil and repeated deformation. The copolymer rubber has in its polymer chain (1) 10 to 60% by weight of units derived from an unsaturated nitrile, (2) 0 to 30% by weight of units derived from a conjugated diene and (3) 10 to 90% by weight of units derived from an ethylenically unsaturated monomer other than unsaturated nitriles and/or units formed by hydrogenating units derived from a conjugated diene.

Abstract: An impact-resistant phenolic resin composition comprising 99 to 25% by weight of a phenolic resin and 1 to 75% by weight of a nitrile group-containing highly saturated polymer rubber whose amount of bound nitrile ranges from 10 to 60% by weight and having an iodine value not exceeding 120.

Abstract: A method of preventing degradation of vulcanized rubber materials used in the operation of oil and gas wells comprising forming said rubber material from a sulfur vulcanized composition comprising a copolymer rubber having in the polymer chain (I) 10 to 60% by weight of a unit from an unsaturated nitrile, (II) not more than 10% by weight of a unit from a conjugated diene, and (III) 30 to 90% by weight of a unit from an ethylenically unsaturated monomer other than the unsaturated nitrile and/or a unit resulting from the hydrogenation of a unit from a conjugated diene, said rubber being vulcanized with a sulfur vulcanization system.