Japan Synthetic Rubber Co., Ltd.

Toshiba Silicone Co., Ltd.

Yasuhiko Takemura

Hiroji Enyo

Toshio Miyabayashi

Yoshiaki Zama

Shin-ichiro Iwanaga

Hozumi Sato

Teizo Kotani

Yoshiharu Hashiguchi

Shinichiro Zen

Itsuki Umeda

Yoshiaki Kawamura

Junichiro Watanabe

Nobuyuki Sakabe

Kunio Goshima

Kiyoshi Takeda

Masato Sakai

Masaaki Takashima

Yoshiyuki Udagawa

Yuichi Funabashi

Minoru Tanaka

Yasuo Takeuchi

Hisao Ono

Makoto Matsumoto

Takashi Ishida

Toshio Teramoto

Takumi Miyachi

Masanobu Nagano

Isao Furuta

Hironori Matsumoto

Yoji Mori

Tatsuaki Matsunaga

Hideo Katsumata

Minoru Hasegawa

Masaaki Watanabe

Hiromichi Yoshida

Motokazu Takeuchi

Yoshiyuki Higuchi

Humito Shimada

Tadaaki Nishi

Akio Sakaguchi

Hiroyuki Sasanuma

A hydrogenated block copolymer or hydrogenated block copolymer mixture consisting essentially of (a) hydrogenation product of a star-branched block copolymer represented by the structural formula (A-B).sub.n X wherein A is a polybutadiene block having a 1,2-vinyl content of less than 25% by weight and B is a copolymer block containing 50% by weight or more of a conjugated diene compound whose vinyl content is 25% by weight or more, X is a coupling agent residue and n is an integer of 3 or more, and (b) a hydrogenation product of a straight chain block copolymer represented by the structural formula A-B wherein A and B are as defined above, the weight ratio of the component (a) to the component (b) being 100/0 to 5/95, and a hydrogenated block copolymer composition comprising (I) 1 to 99 parts by weight of said hydrogenated block copolymer or hydrogenated block copolymer mixture and (II) 99 to 1 part by weight of a thermoplastic resin and/or a rubbery polymer. Said hydrogenated block copolymer or hydrogenated block copolymer mixture can be pelletized and is excellent in the improving effect on impact resistance, heat resistance, stiffness, processibility and appearance of molded article when used as a quality-improving agent for a thermoplastic resin. Said hydrogenated block copolymer composition is a composition having excellent balance of impact resistance, heat resistance, stiffness, processibility and appearance of molded article or a thermoplastic elastomer having excellent mechanical properties.

Hydrogenated block copolymer and hydrogenated block copolymer compositon

A catalyst composition comprising: (a) a bis(cyclopentadienyl) transition metal compound, (b) at least one polarized compound selected from the group consisting of carbonyl group-containing compounds and epoxy group containing compounds, and (c) an organic lithium compound. It has a high hydrogenation activity and is useful for hydrogenating olefinically unsaturated polymers for providing the olefinically unsaturated polymers with excellent characteristics as superior weatherability, good heat resistance, superb oxidation resistance, and the like.

Catalyst composition for hydrogenating olefinically unsaturated polymers

A hydrogenation catalyst composition comprising, as essential components, (a) at least one bis(cyclopentadienyl)transition metal compound represented by general formula (i): ##STR1## and (b) at least one member selected from the group consisting of complex compounds represented by general formulas (ii) and (iii): ##STR2## and further comprising, if necessary, (c) at least one polar compound selected from the group consisting of ether compounds, thioether compounds, ketone compounds, sulfoxide compounds, carboxylic acid ester compounds, lactone compounds, amine compounds, amide compounds, nitrile compounds and oxime compounds and/or (d) an alkali compound represented by general formula (iv):

Hydrogenation catalyst composition and process for hydrogenating

A rubber composition obtained by compounding (B) from 0.005 to 50 parts by weight of an polyorganohydrogensiloxane and (C) from 0.00001 to 1 part by weight of a compound of a transition metal belonging to the group VIII with (A) 100 parts by weight of a rubber-forming polymer mainly comprising (I) from 3 to 70% by weight of a polyorganosiloxane represented by the formula: ##EQU1## wherein R represents a substituted or unsubstituted monovalent organic group, 0.02 to 10 mole % of which being a vinyl group; and a represents a number of from 1.900 to 2.004,

Rubber composition, and oil seal and rubber hose obtained therefrom

A conjugated diene copolymer comprising (A) 10 to 60 mole % of a conjugated diene compound unit, (B) 5 to 50 mole % of an .alpha.,.beta.-ethylenically unsaturated carboxylic acid unit, (C) 0.1 to 20 mole % of a polyfunctional alkenyl compound unit, (D) 0 to 10 mole % of a diene compound unit having cyclic carbon-carbon double bonds and (E) 0 to 80 mole % of a monoolefinically unsaturated compound unit, the sum of the amounts of units (A), (B), (C), (D) and (E) being 100 mole %, said copolymer having an intrinsic viscosity [.eta.] of 0.01 to 3.0 dl/g as measured at 30.degree. C. in dimethylformamide. The copolymer is soluble in aqueous alkali solutions, excels in processability and photosetting property, and has excellent rubber elasticity and transparency even after photosetting. Accordingly, a photosensitive composition comprising the copolymer, a photopolymerizable unsaturated monomer and a photosensitizer can greatly improve the complicated process for the production of conventional rubber relief plates of flexographic printing, and shorten the production time.

Conjugated diene copolymer, a process for producing the copolymer, and a

A vulcanizable rubber composition comprising (1) 100 parts by weight of a polymer composition comprising

Novel vulcanizable rubber compositions and applications thereof

A thermoplastic elastomer composition which comprises 25-95% by weight of a polyamide and 75-5% by weight of a halogenated butyl rubber, a chlorosulfonated polyethylene or both thereof. Said composition is excellent in resistance to Freon gas permeation and has good oil resistance and low-temperature resistance. A hose wherein the layer to be contacted with a gas is made of the above thermoplastic elastomer composition is suitable as a Freon gas R-22 hose.

Thermoplastic elastomer composition and Freon gas hose made thereof

A rubber composition that is prepared by reacting an organic peroxide, under shear deformation, with 3-70 parts by weight of silicone rubber (I), 30-97 parts by weight of a saturated elastomer (II) that substantially fails to be crosslinked with an organic peroxide when it is used alone, and 0-20 parts by weight of another elastomer (III) that is co-crosslinkable with component (I) in the presence of an organic peroxide and which is also co-crosslinkable or highly miscible with component (II) [where (I)+(II)+(III)=100 parts by weight].

Rubber composition and vulcanized rubber product

A rubber composition obtained by subjecting a mixture of (I) 35-95 parts by weight of a fluoroelastomer and (II) 65-5 parts by weight of an ethylene-.alpha.-olefin copolymer rubber in which the total of the (I) component and the (II) component is 100 parts by weight and a crosslinking agent for the ethylene-.alpha.-olefin copolymer rubber (II) to reaction while imparting shearing deformation to the mixture. Said rubber composition is excellent in processability on roll and in extruder, heat resistance, steam resistance, weather resistance, compression set and resistance to compressive load. A rubber article is obtained by subjecting the above rubber composition and a crosslinking agent for the fluoroelastomer (I) and optionally at least one additive to reaction, said rubber article being excellent in heat resistance, weather resistance, compression set and resistance to compressive load and hence can be used in the fields of general industry, electric industry and chemical industry.

Rubber composition derived from fluoroelastomer and

An oil-resistant rubber composition comprising (A) 90 to 10 parts by weight of an unsaturated nitrile-conjugated diene rubber having a .DELTA.Tg of 58.degree. C. or more and an average bound nitrile content of 15 to 50% by weight, (B) 10 to 90 parts by weight of at least one rubber selected from the group consisting of an ethylene-propylene type copolymer rubber, a natural rubber and a polyisoprene and (C) 0 to 50 parts by weight, per 100 parts by weight of the total of (A) and (B), of at least one component (C) selected from the group consisting of a styrene polymer and a polyalkenamer. Said rubber composition is oil-resistant and excellent in mechanical properties such as tear strength, resistance to crack growth, etc.

Oil-resistant rubber composition

A multi-component copolymer rubber consisting essentially of (A) 20 to 69.5% by weight of a cyano-substituted alkyl (meth)acrylate, (B) 30 to 79.5% by weight of an alkyl acrylate, (C) 0.5 to 10% by weight of a crosslinkable monomer and (D) 0 to 10% by weight of other ethylenically unsaturated monomer copolymerizable with (A), (B) and (C), excels in heat resistance, ozone resistance, sour gasoline resistance and sour gasohol resistance. There properties of said multi-component copolymer rubber can further be improved by incorporating into the copolymer rubber a crosslinking agent, a metal salt, a vinylidene fluoride polymer, a vinyl chloride resin or other multi-component copolymer rubber.

Multi-component copolymer rubber, a process for producing the same and a

A resin composition comprising 100 parts by weight of a thermosetting resin and 1 to 100 parts by weight of a functional, rubbery copolymer containing among the monomer units which constitute the copolymer, at least one monomer containing a substituent selected from the group consisting of epoxy, hydroxyl, carboxyl and amino groups, said copolymer being prepared by one of three emulsion polymerization processes in which a nonionic surface active agent and/or ionic surface active agent is employed as the emulsifying agent.

Resin composition comprising a thermosetting resin component and a

A multi-component copolymer rubber consisting essentially of (A) 20 to 69.5% by weight of a cyano-substituted alkyl (meth)acrylate, (B) 30 to 79.5% by weight of an alkyl acrylate, (C) 0.5 to 10% by weight of a crosslinkable monomer and (D) 0 to 10% by weight of other ethylenically unsaturated monomer copolymerizable with (A), (B) and (C), excels in heat resistance, ozone resistance, sour gasoline resistance and sour gasohol resistance. These properties of said multi-component copolymer rubber can further be improved by incorporating into the copolymer rubber a crosslinking agent, a metal salt, a vinylidene fluoride polymer, a vinyl chloride resin or other multi-component copolymer rubber.

Multi-component copolymer rubber, a process for producing the same, and

A rubber composition consisting essentially of 5-99 parts by weight of a thermosetting resin and 94-1 parts by weight of one of the following functional rubber-like copolymers (I) to (III) having a Mooney viscosity ML.sub.1+4.sup.100 of 20-120:

Rubber composition comprising a thermosetting resin and a functional

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Yokkaichi, Japan

Yasuhiko Takemura