To provide a method of producing foamed particles which have a comparatively small shrinkage factor and come to the raw material for obtaining a foamed product having good curing recovery in obtaining molding products of polyester based resin foamed particles having a comparative low density.
In the method of producing polyester based resin foamed particles having a bulk density of 0.008-0.04 g/cm3 comprising a step of heating polyester based resin particles containing not less than 60 mol% aliphatic ester bonds in the main chain with an organic peroxide or with an organic peroxide and an unsaturated compound in a dispersion medium in a close vessel to effect crosslinking of the resin particles, and a step of impregnating the resin particles with a blowing agent, a step of releasing the resin particles impregnated with the blowing agent from the closed vessel under a low pressure to effecting foaming of the resin particles, an organic peroxide having a temperature for giving a half-life of one hour in the range of the Vicat softening temperature of the resin minus 25°C to the Vicat softening temperature plus 10°C is used as the part of the organic peroxide.
| JP7141228 | Packaged goods and transported goods |
SHINOHARA MITSURU
SHIOTANI AKIRA
TOKORO TOSHIO
| JPH10324766A | 1998-12-08 | |||
| JPS60186533A | 1985-09-24 |
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