Kaneka Corporation

Kanegafuchi Kagaku Kogyo Kabushiki Kaisha

Yuichi Ueda

Kiyoshi Mori

Toshiaki Sugita

Hidekazu Oohara

Hideyuki Arakawa

Shotaro Maruhashi

Katsuhiko Wakishige

Foamable modified polystyrene resin particles which are foamable modified polystyrene resin particles (d) comprising modified polystyrene resin particles (c) containing a blowing agent (e); the modified polystyrene resin particles (c) comprising a polystyrene resin and rubber polymer particles (b) being dispersed in the resin, wherein the rubber polymer particles (b) are dispersed uniformly throughout a continuous phase of the polystyrene resin or in a state of a density of the particles (b) being higher in a center portion of the resin particle than in a surface layer portion thereof, and the modified polystyrene resin particles (c) are modified polystyrene resin particles prepared by impregnating a monomer mixture consisting essentially of a styrene monomer and a conjugated diene monomer and comprising the styrene monomer in a larger amount than the conjugated diene monomer, into polystyrene resin particles (a) and carrying out copolymerization.

Expandable styrene resin beads and foams produced therefrom

A method for manufacturing expandable styrene type polymer particles is disclosed, which comprises the steps of adding a styrene type monomer to styrene type polymer seed particles suspended in an aqueous dispersing medium, continuously or intermittently to be polymerized while being absorbed thereby, and impregnating the resulting polymer particles with an easily volatile blowing agent to obtain expandable styrene type polymer particles, the improvement wherein styrene type polymer particles whose weight-average molecular weight (Mw.sub.1) is not more than 2/3 of the weight-average molecular weight (Mw.sub.2) of the resulting polymer particles are used as said styrene type polymer particles. The present invention provides expandable styrene type polymer particles excellent in moldability and foamed articles high in strength and fine in external appearance.

Method for manufacturing expandable styrene type polymer particles

Growing community of inventors

Takasago, Japan

Yuichi Ueda