Momentive Performance Materials Japan LLC

Masanari Shimakawa

Kikuo Mochizuki

Hiroyoshi Iijima

Hidefumi Tagai

Toshihiko Matsukura

Kazuki Shinbo

A polyorganosiloxane composition for molding includes: (A) a straight-chain polyorganosiloxane having two or more alkenyl groups and having a viscosity (25&#xb0; C.) of 10,000 to 500,000 mPa&#xb7;s; (B) 30 to 80 mass % of a resinoid polyorganosiloxane including M, D, and Q units, at a molar ratio of a:b:c, on average (0.3&#x2264;a&#x2264;0.6, 0&#x2264;b&#x2264;0.1, 0.4&#x2264;c&#x2264;0.7, and a+b+c=1), and having two or more alkenyl groups; (C) an amount of a polyorganohydrogensiloxane having Si-bonded hydrogen atoms, an average degree of polymerization of 10 or more, a content of the Si-bonded hydrogen atoms of 5.0 mmol/g or more and 11.0 mmol/g or less, and a mass decrease rate up to 140&#xb0; C. by TGA of 2.0 mass % or less so that an amount of the (Si-bonded hydrogen atoms/alkenyl groups) is 1.0 to 3.0 mol; and (D) a hydrosilylation reaction catalyst. A cured product excellent in mold release property is obtained and contamination of a metal mold is prevented.

Polyorganosiloxane composition for molding, optical member, light source lens or cover, and molding method

There is provided a silicone rubber composition that has improved moldability, in particular, extrusion moldability, while ensuring that a cured product obtained therefrom has sufficient strength. The silicone rubber composition contains: (A) a 100 part by mass base polymer consisting of (A1) a polyorganosiloxane diol whose viscosity at 25&#xb0; C. is 1 to 100 Pas and (A2) a polyorganosiloxane whose viscosity at 25&#xb0; C. is 0.2 to 40000 Pas, with a ratio of (A1) being 20 to 100% by mass to the whole (A), the base polymer having a viscosity of 5 to 20000 Pas at 25&#xb0; C. and having an alkenyl group content of 0.001 to 0.3 mmol/g; (B) a 10 to 50 part by mass silica powder whose specific surface area is 50 to 400 m/g; (C) a 1 to 10 part by mass organosilazane; and (D) a catalytic amount of a curing agent.

Silicone rubber composition, method of producing the same, and silicone rubber extrudate

There are provided a composition for silicone rubber foam, a manufacturing method of a silicone rubber foam, and a silicone rubber foam in which it is possible to control the foaming states. The composition for silicone rubber foam contains: (A) 100 parts by mass of polyorganosiloxane having a degree of polymerization of 4,000 to 10,000 and having two or more alkenyl groups at a content of 0.001 mmol/g or more and less than 0.3 mmol/g; an amount of polyorganohydrogensiloxane having an average of two or more Si-atom-bonded hydrogen atoms so that a molar ratio of the hydrogen atoms to the alkenyl groups in the (A) component is 0.001 to 5; 0.1 to 10 parts by mass of an organic foaming agent with a decomposition temperature of 50 to 250&#xb0; C.; 5 to 200 parts by mass of silica powder; and a catalyst amount of a platinum-based metal catalyst activated with ultraviolet rays.

Composition for silicone rubber foam, manufacturing method of silicone rubber foam, and silicone rubber foam

Provided is a resin composition with high dielectric insulation properties that has a dielectric constant of at least 20, a dielectric tangent of 0.1 or less, outstanding insulation properties (at least 10&#x3a9;&#xb7;cm), and for use in electrical power, communication devices, and the like. A resin composition with high dielectric insulation properties comprises a constituent (A), which is 100 parts by mass of a polymer material that acts as a dispersion medium for constituent (B), and a constituent (B), which is 100-3000 parts by mass of a perovskite complex oxide powder comprising secondary particles formed by the mutual bonding of primary particles through sintering and represented by the formula: ABO.

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Tokyo, Japan

Masanari Shimakawa