Sumitomo Chemical Company, Limited

Sumitomo Rubber Industries Limited

Toyota Jidosha Kabushiki Kaisha

Mitsui Chemicals, Inc.

Yabuta, Takuzoh

Saito, Yuichi

Takao, Hiroyoshi

Tsuji, Mitsuji

Imai, Akio

Mitsuji Tsuji

Akio Imai

Hiroyoshi Takao

Takashi Sanada

Takeshi Fujii

Susumu Kanzaki

Yuichi Saito

Kentaro Yamaguchi

Keisaku Yamamoto

Kazuki Wakamatsu

Hiroomi Abe

Motonobu Furuta

Mitsuyuki Okada

Yasurou Suzuki

Takashi Maruyama

Yoshiki Toyoshima

Taichi Nishio

Tatsuyuki Mitsuno

Kizuku Wakatsuki

Masashi Aoshima

Takayuki Okada

Eiichi Usuda

Takao Nomura

Takeyoshi Nishio

Kenji Nagaoka

Hideo Shinonaga

Ikunori Sakai

Nobuyuki Yoshida

Takayuki Nagai

Hironobu Shigematsu

Yoshio Tanimoto

Kenji Atarashi

Moriyasu Shimojo

Tomoaki Seki

Kouji Satou

Toshio Yokoi

Toru Fukumoto

Takeru Wadaki

Takeshi Sekito

Kazuhiro Doi

Shuji Imaoka

Takuzoh Yabuta

Tomoski Seki

Kenichiro Yada

Syunji Yunoki

Nabuyuki Yoshida

A polypropylene resin composition comprises (A) (a-1) a specific crystalline propylene/ethylene block copolymer or (a-3) a polymer mixture comprising the (a-1) and (a-2) a specific crystalline propylene-homopolymer in specific ratio, in an amount of 5 to 56% by weight, (B) a hydroxyl group-containing polypropylene having an intrinsic viscosity [&#x3b7;] of 0.8 to 2.0 dl/g and a melting point of 150 to 168&#xb0; C., in an amount of 10 to 45% by weight, (C) a copolymer rubber of ethylene and an &#x3b1;-olefin having a melt flow rate (ASTM D-1238, 230&#xb0; C., load of 2160 g) of 0.5 to 15 g/10 min, in an amount of 18 to 25% by weight, (D) a hydrogenation product of a block copolymer containing a polymer block of a monovinyl-substituted aromatic hydrocarbon compound and a polymer block of a conjugated diene compound, in an amount of 1 to 10% by weight, and (E) an inorganic filler in an amount of 15 to 25% by weight, the total amount of said components (A), (B), (C), (D) and (E) being 100% by weight, hydroxyl group-containing monomer units derived from the hydroxyl group-containing polypropylene (B) being contained in amounts of 1.3 to 4.0% by weight in 100% by weight of the polypropylene resin composition. The polypropylene resin composition exhibits excellent coating adhesion properties and has excellent processability and mechanical strength with a good balance.

Polypropylene resin compositions

A polypropylene-based resin composition comprising 0.5 to 10% by weight of a propylene-based polymer component (A1) obtained by polymerizing a monomer mainly composed of propylene, having an intrinsic viscosity &lsqb;&eegr;&rsqb; measured in tetralin at 135&deg; C. of 5 dl/g or more and a melting peak temperature Tm measured by a differential scanning calorimeter of 130 to 160&deg; C., 90 to 99.5% by weight of a propylene-based polymer component (A2) obtained by polymerizing a monomer mainly composed of propylene, intrinsic viscosity &lsqb;&eegr;&rsqb; measured in tetralin at 135&deg; C. of less than 5 dl/g.

Polypropylene-based resin composition, process for producing the same and injection molded article

A propylene-based polymer having a melt flow rate of 0.1 to 20 g/10 min. and a melting point Tm (&deg; C.) measured by using a differential scanning calorimeter (DSC) of 147 to 159&deg; C., in which the half width HW (&deg; C.) of the melting peak measured by using a differential scanning calorimeter (DSC) and the melting point Tm (&deg; C.) satisfy the relation: HW&lE;(188&minus;Tm)/5.

Propylene-based polymer and film made of the same

Polypropylene resin composition

A thermoplastic resin composition superior in impact resistance, heat resistance, flexural rigidity, processability and solvent resistance which comprises: (A) 100 parts by weight of a resin composition comprising 5-95% by weight of a polyphenylene ether, or a polyphenylene ether and polystyrene, and 95-5% by weight of a polyamide resin; (B) 5-50 parts by weight of a modified saturated rubber obtained by grafting 5-100 parts by weight of an aromatic vinyl compound on 100 parts by weight of a saturated type rubber and allowing 0.05-10 parts by weight of a compatibilizing agent to react with said rubber; and (c) 0.05-20 parts by weight of a compatibilizing agent.

Thermoplastic resin composition

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. The tread rubber composition can be processed without causing bagging with a good dispersibility of carbon black and provides tires having a low rolling resistance and a high grip characteristic.

Rubber composition for tire treads

A vulcanizable rubber composition comprising an ethylene-.alpha.-olefin copolymer modified with an alkenyl aromatic compound alone or in combination with at least one other polymerizable compound, as a polymer component. The vulcanizable rubber composition is excellent in weather-resistance, ozone-resistance and heat-resistance and has a high strength, a high rigidity and a high hardness.

Vulcanizable rubber composition and vulcanized rubber product

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.sub.1+4, 100.degree. C.) is from 30 to 200. The butadiene copolymer has an improved processability with excellent resilience, wet grip property, abrasion resistance and mechanical properties, and is suitable for tire use.

Butadiene copolymer and process for preparing same

Disclosed are thermoplastic resin compositions, comprising:

An adhesive composition comprising a modified, ethylene/.alpha.-olefin copolymer rubber or a modified, ethylene/.alpha.-olefin/non-conjugated diene copolymer rubber containing 0.1-10% by weight of at least one member selected from the group consisting of an acid anhydride and a dicarboxylic acid, and, if necessary, as an amine compound,

Growing community of inventors

Ichihara, Japan

Mitsuji Tsuji