| 摘要 |
PURPOSE:To obtain the expansion molded body, having heat resistance and good in dimensional stability without causing the deformation or shrinkage even in contact with hot water for a long period by subjecting particles of a mixed resin of a phenylene ethereal resin with a styrenic resin to the expansion molding according to a specific method. CONSTITUTION:An inorganic gas such as CO2 is initially pressed into particles of a mixed resin of 10-80wt.% phenylene ethereal resin with 90-20wt.% styrenic resin to provide expandable particles containing >=0.05mol inorganic gas in 1kg resin. The resultant particles are then heated with pressurized steam having a lower temperature than the Vicat softening point of the resin by 10 deg.C to a higher temperature than the Vicat softening point by 20 deg.C and primarily expanded. The inorganic gas is subsequently repressed into the preexpanded particles to afford secondarily expandable particles containing >=0.5mol inorganic gas in 1kg resin. The particles filled in a forming metallic mold are finally brought into contact with pressurized steam having the temperature, thermally expanded and mutually fused to provide the objective molded body. |
