Toyoda Gosei Co., Ltd.

Nippon Zeon Company, Ltd.

Denki Kagaku Kogyo Kabushiki Kaisha

Eiwa Chemical Ind. Co., Ltd.

Tomoaki Okita

Katsumi Nakashima

Takashi Mizushima

Masayoshi Ichikawa

Hitoshi Kondo

Yasushi Abe

Hidenari Nakahama

Masatoshi Sugimoto

Shigelu Yagishita

Takeru Wadaki

Gunpei Katsumura

Hiroaki Shimizu

Norikazu Mayama

A method of molding a rubber product from a rubber compound by a molding apparatus having a kneading region. A full amount of carbon black (CB) and a full amount of process oil, together with other auxiliary materials except vulcanizing chemicals, are compounded with raw rubber to thereby knead and prepare a granular master batch (granular MB) . The rubber product is extrusion-molded and vulcanized after vulcanizing chemicals (a vulcanizing agent and a vulcanization accelerator) are quantitatively supplied into the kneading region of the molding apparatus through a material supply port while the vulcanizing chemicals are mixed with the granular MB.

Method for molding rubber product

Kneaded rubber for expandable formulation

A formed rubber extruded product which is formed of a vulcanizate of a rubber blend comprising a sulfur-vulcanizable ethylene-propylene-type rubber (EPDM) as a starting rubber and a pyrolytic foaming agent. The vulcanizate has a specific gravity of from 0.9 to 1.0 and a surface roughness (RZD) of 14 micrometers or less. The rubber blend contains the pyrolytic foaming agent in the form of an inorganic powder-supported foaming agent. A particle diameter of the inorganic powder in the inorganic powder-supported foaming agent is approximately 9 micrometers or less, and a particle diameter of the pyrolytic foaming agent is approximately 8 micrometers or less. Further, crystalline PE is contained in an amount of from 6 to 30 parts per 100 parts of EPDM. The foamed rubber extruded product of the present invention can be produced by the extrusion at a high rate.

Foamed rubber extruded product

A foam rubber composition and a method for making same which is foamable to a high degree and a molded product made from the foam rubber composition wherein the compositions has: (A) a low-molecular Ethylene-propylene-5-ethylidene-2-norbornene terpolymer having a Mooney viscosity (ML.sub.1+4 at 100.degree. C.) of 20 to 40, an ethylene/propylene ratio by weight of 65/35 to 50/50, an iodine value of 20 to 30, and a Q value (Mw/Mn) not exceeding 3 as determined by gel permeation chromatography; (B) a high-molecular ethylene-propylene-5-ethylidene-2-norbornene terpolymer having a Mooney viscosity (ML.sub.1+4 at 100.degree. C.) of 100 to 300, an ethylene/propylene ratio by weight of 65/35 to 50/50, an iodine value of 20 to 30 and a Q value (Mw/Mn) of 6 to 10; (C) a vulcanizing system agent containing sulfur as a vulcanizer, and zinc carbamate and sulfenamide as accelerators; and (D) a foaming agent containing N, N'-dinitrosopentamethylenetetramine and urea.

Foam rubber composition and a molded product of foam rubber

A foamed rubber blend comprising an EPDM is polymer blend comprising at least one high molecular weight component and at least one low molecular weight component is provided. The high molecular weight component has a weight average molecular weight (Mw) in a range of from about 400,000 to about 800,000 and a molecular weight distribution index (Mw/Mn) in a range of from about 5.5 to about 9.5. The low molecular weight component has a weight average molecular weight (Mw) in a range of from about 150,000 to about 500,000 and a molecular weight distribution index (Mw/Mn) in a range of from about 1.5 to about 5.5. The EPDM rubber has an overall weight average molecular weight (Mw) in a range of from about 200,000 to about 700,000. The ratio of the polymer blend in the foamed rubber blend is in a range of from about 33 wt % to about 60 wt %. The present invention is also directed to an article formed from a sulfur-vulcanized EPDM rubber blend having a compression set according to JIS K 6301 of not more than about 24%.

Foamed rubber blend containing and ethylene-propylene-diene polymer

A multi-layer rubber hose in which a fluorinated rubber (FKM) layer and a nitrile rubber (NBR) layer adjacent thereto have been vulcanization-adhered to each other. The FKM layer is formed from the vulcanizate of an FKM compound containing a ternary FKM as a polymer component. The vulcanization system is an organic polyol system and a quaternary ammonium salt, and the vulcanization induction time (T.sub.10) satisfies the following equation, 4 minutes .ltoreq.T.sub.10 +determined vulcanization temperature -170.degree. C.) minutes/10.degree. C..ltoreq.7 minutes. The NBR layer is formed from the vulcanizate of the NBR compound, and the NBR comound is a stock rubber into which a functional group having an active hydrogen has been introduced. The vulcanization system is an oragnic peroxide system. The multi-layer rubber hose of the presnt invention is suitable as a fuel hose for cars and has a high resistance to gasohol.

Multi-layer rubber hose and method for producing the same

A curable elastomeric composition comprising an epoxy group-containing acrylate-type elastomer in combination with (1) a polycarboxylic acid or its anhydride, (2) a quaternary ammonium or phosphonium salt and (3) a urea.

Curable acrylate-type elastomer composition

An acrylic rubber composition comprising (A) a copolymer and (B) a crosslinking agent, said copolymer (A) consisting essentially of (a) from 3 to 10% by weight of ethylene, (b) from 0 to 10% by weight of at least one crosslinkable monomer selected from the group consisting of monomers of the formulas (1), (2), (3) and (4): ##STR1## wherein R.sub.1 is hydrogen or methyl, ##STR2## wherein R.sub.2 is vinyl, allyl or methallyl, ##STR3## wherein R.sub.3 is hydrogen or methyl,

Growing community of inventors

Kasugai, Japan

Tomoaki Okita