| 摘要 |
PROBLEM TO BE SOLVED: To provide expandable particles from recovered styrene resins capable to give high quality foams without drawbacks such as uneven foaming in preliminary foamed particle, molded product with uneven foams and insufficient fusion showing gaps or uneven surface, which are caused conventionally. SOLUTION: The expandable particles are prepared by the steps of preparing fragment lots by crushing the recovered styrene resin, determining the volume of solvent contained in each lot, combining a plurality of lots to give resin mixtures containing 2 wt.% or less of the solvent, melting the crushed fragments in an extruder, adjusting the amount of solvent to 0.2-2 wt.% by adding a solvent forcibly into the resin when the solvent content of the melted mixture remains less than 0.2 wt.%, adding a foaming agent forcibly in the extruder, extruding the pressurized content into a pressurized fluid from the extruder, cool while under unfoaming state and cut to give expandable particles. COPYRIGHT: (C)2004,JPO
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