Abstract: A propylene copolymer comprising propylene, at least one olefin selected from the group consisting of olefins having 2 to 20 carbon atoms except propylene, and a cyclic olefin, wherein the total number of carbon atoms of the monomers except the cyclic olefin is at least 7. This copolymer is mixed with a thermoplastic resin such as polypropylene to provide a thermoplastic resin composition having excellent flexibility, transparency, resistance to whitening on bending, scratch resistance and heat resistance.

Abstract: A propylene copolymer obtainable by polymerizing a propylene, at least one of .alpha.-olefin having 4-20 carbon atoms, and ethylene, in the presence of a catalyst for olefin polymerizaton including the following (A), (B) and/or (C):(A) at least one transition metal complex;(B) at least one aluminum compound; and(C) boron compound.

Abstract: A rubber composition obtained by kneading a mixture comprising 100 parts by weight of a solution polymerized diene rubber, 5-100 parts by weight of silica, 1-15 parts by weight of a silane coupling agent, and 1-20 parts by weight of an organic silicon compound having a number average molecular weight of about 100-10,000, and maintaining the temperature during the kneading at 200.degree. C. or less. The composition is excellent in wear resistance and productivity, has lower rolling resistance and is useful, for example, for automobile tires.

Abstract: Provided is a rubber composition obtainable by kneading a mixture at a maximum temperature between about 120.degree. to about 170.degree. C. The mixture includes:100 parts by weight of a solution polymerized diene rubber;about 5 to about 100 parts by weight of silica;about 1 to about 15 parts by weight of a silane coupling agent; andabout 1 to about 15 parts by weight of a polyalkylene glycol having a weight average molecular weight of about 200 to about 20,000.The invention also provides a method for making the rubber composition, a tire tread made from the rubber composition, and a tire made from the rubber composition.

Abstract: A composition is disclosed which contains about 80.0 to about 99.9% by weight of a (meth)acrylate monomer having a structure represented by a formula (I) or a mixture of the (meth)acrylate monomer and alkyl acrylate having an alkyl ester comprising alcohol of 1 to 8 carbon atoms, and about 20.0 to about 0.1% by weight of a crosslinking monomer copolymerizable with the (meth)acrylate monomer. The composition can be used in formulating elastomeric compositions having a favorable balance of properties.

Abstract: An automotive weather strip comprising a base material, a urethane layer and an adhesive composition formed between the base material and the urethane layer, wherein said base material comprises an ethylene/propylene rubber and said adhesive composition comprises components (A) to (E), the weight ratio of component (A) to component (B) being 60:40 to 40:60,(A) an epoxy group-containing acrylic elastomer,(B) an ethylene/.alpha.-olefin copolymer,(C) an organic peroxide,(D) at least one member selected from the group consisting of a primary amines and an imidazole compound, and(E) calcium oxide.The present invention can provide an automotive weather strip in which a base material containing the ethylene/propylene rubber has been strongly adhered to the urethane layer forming a surface layer, and which can be produced efficiently without requiring many production steps and also without using a hygienically undesirable solvent-containing adhesive.

Abstract: A rubber composition is provided which comprises 100 parts by weight of ethylene-(meth)-acrylate copolymer rubbers and/or ethylene-(meth)-acrylate-unsaturated glycidyl ester copolymers, 5 to 300 parts by weight of a hydroxide of a typical metallic element belonging to Group II or III of the Mendeleev's periodic table and 0.1 to 50 parts by weight of a metallic acrylate compound. This composition keeps properties required for rubbers such as tensile strength, elasticity, scorch resistance and processability at high levels and is excellent in wear resistance and flame retardance.

Abstract: A process for producing ethylene-.alpha.-olefin copolymer rubbers which comprises mixing a vanadium compound-containing solution and an alcohol-containing solution with stirring for 10-600 seconds to obtain a mixed solution, immediately feeding the mixed solution into a polymerization vessel containing an organoaluminum compound, and copolymerizing ethylene and an .alpha.-olefin, or ethylene, an .alpha.-olefin and a non-conjugated diene compound in the polymerization vessel. According to this process, the activity of polymerization catalyst can be maintained at a high level, no by-product of the reaction of the vanadium compound and the alcohol is deposited as precipitate in the apparatus and no such additional operations as bubbling is necessary.

Abstract: A rubber composition for sponge rubber which contains following components (A).about.(E) and satisfies the following requirements that the ratio by weight of (A)/(B) is 30/70.about.99/1 and the amount of component (C) is 50.about.400 parts by weight per 100 parts by weight of the total amount of components (A) and (B):(A): Epoxy group-containing acryl elastomer.(B): Ethylene copolymer which contains a carboxyl group(s) or a carboxylic anhydride group(s).(C): Hydroxyl compound of II or III group of typical metal element in periodic table.(D): Vulcanizer.(E): Foaming agent.The sponge rubber compositions of the invention can be used for sponge for insulator in the field of electricity, architecture, automobile and the like, because sponge rubber compositions of the invention have the characteristics of good heat resistance, good oil stability, high-foaming property, and good shape-retention.

Abstract: A graft polymer wherein an iodine-containing fluororubber has been grafted on an ethylene-.alpha.-olefin copolymer or other polymer can be obtained by mixing 30 parts by weight of an iodine-containing fluororubber (a vinylidene fluoride-hexafluoropropylene copolymer containing iodine) and 70 parts by weight of an ethylene-propylene copolymer rubber at 180.degree. C. for 30 minutes while applying shear deformation using a Brabender mixer.

Abstract: A rubber composition is provided which comprises 100 parts by weight of ethylene-(meth)acrylate copolymer rubbers and/or ethylene-(meth)acrylate-unsaturated glycidyl ester copolymers, 5 to 300 parts by weight of a hydroxide of a typical metallic element belonging to Group II or III of the Mendeleev's periodic table and 0.1 to 50 parts by weight of a metallic acrylate compound. This composition keeps properties required for rubbers such as tensile strength, elasticity, scorch resistance and processability at high levels and is excellent in wear resistance and flame retardance.

Abstract: A rubber composition for tire treads comprising a rubber component consisting essentially of (A) 20 to 100% by weight of a solution-polymerized styrene-butadiene copolymer rubber having a Mooney viscosity ML.sub.1+4 of 30 to 200 at 100.degree. C. prepared by copolymerization of styrene, butadiene and a polyvinyl aromatic compound followed by coupling with a trifunctional or tetrafunctional coupling agent, and (B) 0 to 80% by weight of at least one rubber selected from the group consisting of an emulsion-polymerized styrene-butadiene rubber, a butadiene rubber, natural rubber and a synthetic polyisoprene rubber; and (C) 50 to 250 parts by weight of a carbon black having an iodine adsorption number of not less than 60 mg/g and an oil absorption of not less than 110 ml/100 g per 100 parts by weight of said rubber component; the tan .delta. peak temperature Tg of the cured product of said rubber composition being from -40.degree. to +5.degree. C.

Abstract: A rubber composition which is vulcanizable with organic peroxides and provides vulcanized rubber excellent in oil resistance, heat resistance, low-temperature resistance and compression set.

Abstract: A vulcanizable epoxy group-containing elastomer composition is disclosed, comprising (A) an epoxy group-containing elastomer, (B) an organic compound containing at least two ##STR1## bonds, wherein X and Y, which may be the same or different, each represents an oxygen atom or a sulfur atom, per molecule or an organic compound containing at least two carboxyl groups per molecule, and (C) a phosphine compound represented by formula: ##STR2## wherein R.sub.1 and R.sub.2, which may be the same or different, each represents an alkyl group having from 1 to 4 carbon atoms; and R represents a hydrogen atom or an alkoxy group having from 1 to 4 carbon atoms. The composition has excellent compression set, particularly in a high temperature atmosphere, as well as excellent mechanical characteristics.

Abstract: An elastomeric butadiene copolymer prepared by a process which comprises copolymerizing butadiene, a polyvinyl aromatic compound and optionally styrene in a hydrocarbon solvent in the presence of an organolithium polymerization initiator and subjecting the resulting copolymer having lithium at the polymer end or ends to a coupling reaction with a trifunctional or tetrafunctional coupling agent, said butadiene copolymer satisfying the following conditions: (a) the content of styrene is at most 50% by weight, (b) the content of vinyl bonds in the butadiene portion is from 10 to 90% by weight, (c) the molecular weight distribution curve obtained by a high performance liquid chromatography has at least three peaks, and 5 to 60% by weight of all the polymer chains have a molecular weight which is at least 5 times the molecular weight in terms of standard polystyrene corresponding to the peak appearing on the lowest molecular weight side of the high performance liquid chromatogram, and (d) the Mooney viscosity (ML.

Abstract: A vulcanized rubber composition which is obtained by vulcanizing a modified ethylene-.alpha.-olefin-nonconjugated diene copolymer rubber composition defined below with sulfur or organic peroxides, said modified rubber composition comprising an ethylene-.alpha.-olefin-nonconjugated diene copolymer rubber modified with 0.01-0.15% by weight of an unsaturated carboxylic acid or a derivative thereof on the basis of the modified ethylene-.alpha.-olefin-nonconjugated diene copolymer rubber and at least one dinitroamine represented by the following formula (A): ##STR1## wherein X represents a divalent chain aliphatic, cyclic aliphatic or aromatic group which may contain a halogen or oxygen, R.sup.1 represents a hydrogen atom, a chain aliphatic group, a cyclic aliphatic group or an aromatic group with a proviso that when both X and R.sup.1 represent a chain aliphatic group, nitrogen atoms may further link to each other through R.sup.1, and R.sup.2 and R.sup.

Abstract: A graft polymer wherein an iodine-containing fluororubber has been grafted on an ethylene-.alpha.-olefin copolymer can be obtained by mixing 30 parts by weight of an iodine-containing fluororubber (a vinylidene fluoride-hexafluoropropylene copolymer containing iodine) and 70 parts by weight of an ethylene-propylene copolymer rubber at 180.degree. C. for 30 minutes while applying shear deformation using a Brabender mixer.

Abstract: The present invention provides a rubber composition which comprises the following components (A) and (B):(A) an ethylene copolymer rubber comprising ethylene and at least one compound selected from the group consisting of acrylic esters and methacrylic esters as constituting units, and(B) a hydrogenated unsaturated nitrile-conjugated diene copolymer rubber.This composition is well balanced in its properties such as strength characteristics, oil resistance, low-temperature resistance and ozone resistance.

Abstract: A method for purifying an ethylene-.alpha.-olefin olefin having at least 3 carbon atoms, or ethylene with an .alpha.-olefin having at least 3 carbon atoms and a nonconjugated diene compound, in a hydrocarbon solvent in the presence of a catalyst comprising a vanadium compound, an organoaluminum compound, and a halogenated ester compound, the method including a step of mixing and stirring the polymerization reaction mixture obtained by the polymerization reaction in an aqueous alkaline solution in such an amount as to give an aqueous phase having a pH of not lower than 10.0 after mixing and stirring, is disclosed. A method for purifying an ethylene-.alpha.-olefin copolymer is also disclosed, including a step of an oxidation treatment of the polymerization reaction mixture in an aqueous alkaline solution in such an amount as to give an aqueous phase having a pH of not lower than 10.0 after the oxidation treatment.

Abstract: A process for preparing modified diene polymer rubbers having an increased impact resilience, a reduced hardness at low temperatures and an improved processability, and useful as rubber materials for automobile tires and other industries which comprises producing a conjugated diene polymer having alkali metal end or ends, and reacting the alkali metal-containing polymer with (a) a silicon or tin compound of the formula: R.sub.a MX.sub.b wherein R is an alkyl group, an alkenyl group, a cycloalkenyl group or an aromatic hydrocarbon atom, a is 0, 1 or 2 and b is 2, 3 or 4, and (b) at least one member selected from the group consisting of a nitro compound; a phosphoryl chloride compound of the formula (1): ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are an alkyl group; an aminosilane compound of the formula (2): ##STR2## wherein R.sup.5, R.sup.6 and R.sup.7 are an alkyl group or an alkoxyl group, R.sup.8 and R.sup.