Abstract: This invention relates to a composition comprising (A) an ethylene-?-olefin having 3 to 20 carbon atoms-non-conjugated polyene copolymer, (B) a specific fine-powdered silicic acid and/or a silicate having a specific surface area of 5 to 500 m2/g (BET adsorption amount: ISO 5794/1, Annex D), (C) at least one kind of ?,?-unsaturated carboxylic acid metal salts, (D) an organic peroxide, further optionally (E) one antioxidant selected from sulfur-containing antioxidants, phenolic antioxidants and amine antioxidants, and/or (F) sulfur, and this invention relates to a rubber product obtainable by crosslinking the above composition.

Abstract: A propylene polymer composition is prepared by mixing propylene homo- or co-polymer (A) obtained using a transition metal catalyst compound (h), defined herein, with a co-catalyst, e.g., organoaluminum oxy compound, with an olefin elastomer (D) and another olefin polymer (E), e.g., polyethylene. Alternatively, the combination of propylene polymer (A), olefin elastomer (D) and olefin polymer (E) is prepared by a multi-stage polymerization method. In both cases, the propylene homo- or co-polymer (A) may include a second propylene homo- or co-polymer (A?) wherein the ratio of intrinsic viscosities of propylene polymers (A) and (A?) is in the range of 3 to 30. These propylene polymer compositions are excellent in heat resistance, mechanical strength, tensile elongation at break, etc., and can be used in the fabrication of structural materials, films and sheets.

Abstract: The crosslinkable rubber composition of the invention is crosslinkable by hot air, and a hot-air crosslinked rubber sheet thereof has no scratch on the surface in a hardness test using a pencil of HB and has a compression set of not more than 70% after a heat treatment at 150° C. for 22 hours. The rubber composition comprises an ethylene/?-olefin/non-conjugated polyene random copolymer rubber comprising a specific vinyl end group-containing norbornene compound, a SiH group-containing compound having at least two SiH groups in one molecule, and if necessary, an addition reaction catalyst comprising a platinum group element and a reaction inhibitor. The automobile weatherstrip, hose, rubber vibration insulator, belt, sealing material, expanded product, covered electric wire, electric wire joint, electric insulating part and household rubber product according to the invention comprise the above-mentioned rubber composition.

Abstract: The present invention provides a vulcanized foamed rubber molded product which has surface smoothness equal to or higher than that of a non-foamed vulcanized rubber molded product, has excellent mechanical strength properties, compression set resistance and abrasion resistance and a non-foamed vulcanized rubber molded product which is superior in surface smoothness to a conventional non-foamed vulcanized rubber molded product and has excellent compression set resistance, mechanical strength properties and abrasion resistance, as well as a method of producing the same. The molded product of the present invention is characterized in that the amount of sulfur atoms present in the surface thereof is at least 1.2 times as high as the amount of sulfur atoms present in a cut face obtained by cutting the surface to a depth of 1.0 mm in the vertical direction.

Abstract: The crosslinkable rubber composition of the invention is crosslinkable by hot air, and a hot-air crosslinked rubber sheet thereof has no scratch on the surface in a hardness test using a pencil of HB and has a compression set of not more than 70% after a heat treatment at 150° C. for 22 hours. The rubber composition comprises an ethylene/?-olefin/non-conjugated polyene random copolymer rubber comprising a specific vinyl end group-containing norbornene compound, a SiH group-containing compound having at least two SiH groups in one molecule, and if necessary, an addition reaction catalyst comprising a platinum group element and a reaction inhibitor. The automobile weatherstrip, hose, rubber vibration insulator, belt, sealing material, expanded product, covered electric wire, electric wire joint, electric insulating part and household rubber product according to the invention comprise the above-mentioned rubber composition.

Abstract: The first silicon-containing olefin copolymer of the present invention comprises (a) a constituent unit derived from —CH2—CH2—, (b) a constituent unit derived from —CH2—CHR— [R is a hydrocarbon group of 1 to 18 carbon atoms], and (c) a constituent unit containing a specific silicon-containing group, and has a molar ratio [(a)/(b)] of the constituent units (a) to the constituent units (b) of from 99/1 to 30/70, a content of the constituent unit (c) of from 0.1 to 10 mol % based on 100 mol % of the total amounts of the constituent units (a), (b) and (c), and a branching index of not less than 0.70. The second silicon-containing olefin copolymer of the present invention is obtainable by copolymerizing ethylene, an ?-olefin of 3 to 20 carbon atoms and a specific silicon-containing ethylene monomer, and has a molar ratio of ethylene to ?-olefin of from 99/1 to 30/70, an intrinsic viscosity, as measured in decalin at 135° C., of from 0.1 to 10 dl/g, a content of the ethylene monomer of from 0.

Abstract: A rubber composition for fuel cell seals, HDD top cover gaskets or cable connector seals is disclosed. The rubber composition comprises a specific ethylene/?-olefin/non-conjugated polyene copolymer [A], a specific organopolysiloxane [B] and an SiH group-containing compound [C], with the weight ratio of [A]:[B] being 100:0 to 5:95. A fuel cell sealing material, HDD top cover gasket material, cable connector sealing material, fuel cell seal, HDD top cover gasket and cable connector seal according to the present invention comprise the composition. A fuel cell according to the present invention includes the fuel cell seal. A hard disk drive of the present invention includes the gasket. An automotive cable connector according to the present invention is sealed by the composition. The invention provides a crosslinkable rubber composition that has good high-speed moldability and can give fuel cell seals excellent in resistances to heat, acids and gas permeation.

Abstract: A propylene polymer composition comprising a propylene polymer prepared by using a zirconocene catalyst having two aryl-substituted indenyl group and having a melt flow rate (MFR) of 0.01 to 30 g/10 min and a second propylene polymer prepared by using a zirconocene catalyst having a melt flow rate (MFR) of 30 to 1,000 g/10 min and, if desired, a soft polymer, a ratio of the MFR of the second propylene polymer to the MFR of the second propylene polymer being not less than 30. These propylene polymer compositions are excellent in heat resistance, mechanical strength, tensile elongation at break, etc., and hence they can be favorably used for various structural materials such as those of automobile and electrical appliances, daily necessaries, various films and sheets.

Abstract: A propylene polymer composition is prepared by mixing propylene homo- or co-polymer (A) obtained using a transition metal catalyst compound (h), defined herein, with a co-catalyst, e.g., organoaluminum oxy compound, with an olefin elastomer (D) and another olefin polymer (E), e.g., polyethylene. Alternatively, the combination of propylene polymer (A), olefin elastomer (D) and olefin polymer (E) is prepared by a multi-stage polymerization method. In both cases, the propylene homo- or co-polymer (A) may include a second propylene homo- or co-polymer (A′) wherein the ratio of intrinsic viscosities of propylene polymers (A) and (A′) is in the range of 3 to 30. These propylene polymer compositions are excellent in heat resistance, mechanical strength, tensile elongation at break, etc., and can be used in the fabrication of structural materials, films and sheets.

Abstract: A tire provided with a tire tread made from a rubber composition comprising (A) a random copolymer based on non-conjugated cyclic polyene comprising structural units originated from one or more &agr;-olefins (A1) and originated from one or more non-conjugated cyclic polyene (A2), the said random copolymer having a content of the structural unit(s) originated from one or more &agr;-olefins (A1) in the range of 93 to 70 mole %; a content of the structural unit originated from one or more non-conjugated cyclic polyene (A2) in the range of 7 to 30 mole %; an intrinsic viscosity [&eegr;], determined in decalin at 135° C., in the range of 0.01 to 20 dl/g; a glass transition temperature (Tg) of not higher than 40° C.; and an iodine value in the range of 50 to 150, and (B) a rubber based on diene, in a weight proportion of {the random copolymer based on non-conjugated cyclic polyene (A)} versus {the rubber based on diene (B)} in the range from 60/40 to 0.1/99.

Abstract: This invention relates to a rubber composition for extrusion and molding comprising 100 weight parts of ethylene/&agr;-olefin/non-conjugated polyene copolymer (A) composed of ethylene, &agr;-olefin having carbon atoms of 3-20 and non-conjugated polyene, and at least 30-300 weight parts of carbon black (B), and 1.0×10−5-5.0×10−3 mol of an alkoxysilane compound shown by the following formula (I): wherein, R is alkyl or alkoxy, R1 is alkyl or phenyl, n is 0, 1 or 2, R2 is a bivalent hydrocarbon, R3 is arylene group, m and p are 0 or 1 respectively, and m and p are not 0 at a same time, q is 1 or 2, and D is —SCN or —SH when q is 1, and —Sx— when q is 2 (wherein x is an integer of 2-8).

Abstract: The crosslinkable rubber composition is crosslinkable at room temperature, has a gelation time at room temperature of 30 days or less, and can prepare a crosslinked rubber sheet by crosslinking the composition at room temperature, wherein the crosslinked rubber sheet has a tensile elongation of 20% or more, and is free of cracks after treatment at 40° C. in a 50 pphm ozone concentration for 96 hr. Specifically, it comprises an ethylene/&agr;-olefin/non-conjugated polyene random copolymer rubber comprising a norbornene compound having a specific vinyl end group, an SiH group-containing compound, which has at least two SiH groups in one molecule, and optionally a platinum catalyst, a reaction inhibitor and/or a silane-coupling agent. The sealing, potting and coating materials and adhesives of the present invention comprise the above rubber composition.

Abstract: An olefin thermoplastic elastomer composition comprises a crystalline polyolefin resin (A) and an ethylene/&agr;-olefin/nonconjugated polyene copolymer rubber (B), and optionally a softener (C) and/or an inorganic filler (D), in a specific ratio. The copolymer rubber (B) is prepared by the use of a metallocene catalyst and comprises ethylene, an &agr;-olefin of 3 to 20 carbon atoms and a nonconjugated polyene. This composition ca provide molded products of more excellent tensile strength, elongation at break, elastomeric properties (elongation set, permanent compression set, etc.), heat resistance and low-temperature properties than the conventional non-crosslinked olefin thermoplastic elastomers, even if the composition is in the non-crosslinked form. The composition in the partially or completely crosslinked form can provided molded products of more excellent low-temperature properties, tensile strength, elongation at break and elastomeric properties than the conventional vulcanized rubbers.

Abstract: The present invention relates to an olefinic thermoplastic elastomer composition which comprises a crystalline polyolefin resin (A), an ethylene-&agr;-olefin-non-conjugated polyene copolymer rubber (B) and at least on rubber (C) selected from polyisobutylene, butyl rubber and a propylene-ethylene copolymer rubber having a propylene content of 50 mol % or more or an ethylene-&agr;-olefin copolymer (D) having a density of 0.870 to 0.

Abstract: The ethylenic copolymer rubber according to the present invention is a novel and useful ethylenic copolymer rubber which can be cross-linked at a high velocity and is superior in scorching stability, in workability and in moldability, of which cross-linked product is superior in the mechanical properties, such as the cross-linked rubber strength etc., and in the form-preservability. A cross-linkable rubber composition containing this ethylenic copolymer rubber is utilized for producing, for example, cross-linked molded rubber product for use as sealing element and automobile weather strip sponge.

Abstract: The invention provides an ethylene-&agr;-olefin-unconjugated polyene random copolymer rubber having hydrolyzable silyl groups in the molecule, which is crosslinkable with air-borne moisture at room temperature and is not only useful for resin modification, but also applicable as elastic sealants and adhesives, and a method for preparing the same.

Abstract: A blend of a rubber and a rubber modifier, the rubber modifier comprising an ethylene/&agr;-olefin copolymer rubber (A) composed of one or more copolymers selected from the group consisting of a copolymer of ethylene and an &agr;-olefin having 3-20 carbon atoms and a copolymer of ethylene, an &agr;-olefin having 3-20 carbon atoms and a non-conjugated polyene, the copolymer rubber (A) having the parameters: an ethylene/&agr;-olefin mole ratio in the range of 51/49 to 87/13, an intrinsic viscosity [&eegr;] determined in decahydronaphthalene at 135° C. in the range of 0.8 to 2.5 dl/g and an iodine value in the range of 0 to 40.

Abstract: A propylene polymer composition is prepared by mixing propylene home- or co-polymer (A) obtained using a transition metal catalyst compound (h), defined herein, with a co-catalyst, e.g., organoaluminum oxy compound, with an olefin elastomer (D) and another olefin polymer (E), e.g., polyethylene. Alternatively, the combination of propylene polymer (A), olefin elastomer (D) and olefin polymer (E) is prepared by a multi-stage polymerization method. In both cases, the propylene homo- or copolymer (A) may include a second propylene homo- or co-polymer (A′) wherein the ratio of intrinsic viscosities of propylene polymers (A) and (A′) is in the range of 3 to 30. These propylene polymer compositions are excellent in heat resistance, mechanical strength, tensile elongation at break, etc., and can be used in the fabrication of structural materials, films and sheets.

Abstract: According to the present invention, there is provided a rubber composition for a conveyor belt comprising (A) 100 parts by weight of an ethylene/&agr;-olefin containing 3 to 20 carbon atoms/non-conjugated polyene copolymer rubber containing a diene unit derived from special non-conjugated dienes, (B) 0.5 to 15 parts by weight of an organic peroxide, (C) 30 to 80 parts by weight of a carbon black and (D) 5 to 25 parts by weight of a softening agent. This rubber composition provides excellent mechanical strength, heat resistance (including heat aging resistance), abrasion resistance and roll processability. It is especially preferred to convey a sintered product, a coke, a cement, clinker and quicklime.

Abstract: The curable composition of the present invention contains (A1) a silyl-containing ethylene/&agr;-olefin/non-conjugated polyene random copolymer rubber which has a structural unit derived from a norbornene compound as the non-conjugated polyene with at least one specific vinyl group at the terminal and contains a specific hydrolyzable silyl group, and (B) a compound, other than the rubber (A1), having a hydroxyl group and/or a hydrolyzable group, e.g., (B1) a compound having a silanol group and/or a compound which can react with moisture to form a compound having a silanol group in the molecule.