Sumitomo Chemical Company, Limited

Tetsuro Dobashi

Kenji Atarashi

Hisakatsu Hama

Disclosed is an injection molded article made of a resin composition comprising 15 to 40% by mass of ultrahigh molecular weight polyethylene fibers, and 60 to 85% by mass of a thermoplastic resin having a melt flow rate of 70 to 500 g/10 min. measured at a temperature of 230&#xb0; C. and a load of 21.2 N, and a fusion peak temperature lower than 160&#xb0; C. measured with a differential scanning calorimeter, where the combined mass of the ultrahigh molecular weight polyethylene fibers and the thermoplastic resin is taken as 100% by mass, wherein the injection molded article satisfies the following requirements: the intrinsic volume resistivity is 1.0&#xd7;10&#x3a9;&#xb7;cm or more, the thermal conductivity is 1 W/m&#xb7;K or more, and the specific gravity is 1.2 or less. The article is high in rigidity, impact resistance, electrically insulating property, and thermal conductivity.

Injection molded article, and method for producing injection molded article

A production process of an organic fiber-containing polyolefin resin composition includes the step of mixing in a rotary impeller-carrying mixer (1) more than 10 parts by weight to less than 90 parts by weight of an organic fiber, with (2) more than 10 parts by weight to less than 90 parts by weight of a polyolefin resin containing (a) 50 to 100% by weight of polyolefin resin powders passing through a sieve having 2 mm openings, and (b) 0 to 50% by weight of polyolefin resin pellets not passing through a sieve having 2 mm openings and passing through a sieve having 4.75 mm openings.

Process for producing organic fiber-containing polyolefin resin composition

Disclosed is a method for producing a devolatilized polyolefin, wherein the method comprises a step that involves providing a twin screw extruder comprising a resin feeding port, a first molten resin kneading zone, a molten resin partially filled zone which is prevented from being fully filled with molten resin, a second molten resin kneading zone, and a devolatilization zone that are disposed in order from the upstream of a cylinder of the extruder, feeding a polyolefin through the resin feeding port, and feeding water to the molten resin partially filled zone in an amount of 0.01 to 50 parts by weight relative to 100 parts by weight of the polyolefin.

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Ichihara, Japan

Tetsuro Dobashi