摘要 |
PROBLEM TO BE SOLVED: To provide expandable composite resin particles comprising a polyolefin resin and a polystyrene resin and containing pentane, wherein, even if the expandable composite resin particles are pre-expanded without being thawed after frozen-stored, the pre-expanded particle becomes not in a state having a core, or has a low mixing ratio of the pre-expanded particle in a state having a core. SOLUTION: The dry manufacturing method for the expandable composite resin particles comprises an impregnation step of adding pentane as an expanding agent to a composite resin article comprising a polyolefin resin and a polystyrene resin at a temperature within the range of (T+10)°C to (T+40)°C, T(°C) being the boiling point of pentane, in a closed system without using an aqueous medium to impregnate the resin particle with 7.5-11.0 wt.% of pentane, and a freezing step of freezing the pentane-impregnated composite resin particles taken out. COPYRIGHT: (C)2011,JPO&INPIT
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