MANUFACTURE OF POLYPROPYLENE TYPE RESIN FOAMED AND MOLDED ITEM

PURPOSE:To obtain the titled molded item whose weld line is hardly recognized, by feeding a PP type resin, a nucleator and a foaming agent, extruding the mixture from a mouth piece having a plurality of fine bores to a low pressure zone to obtain stringlike foamed bodies, mincing the stringlike foamed bodies, and loading them into a specified mold followed by molding. CONSTITUTION:A polypropylene resin and a nucleator (e.g. talc) are fed into an extruder, and melted and plasticized, then a volatile foaming agent (e.g. trichlorofluoroethane, etc.) is fed from a cylinder of the extruder, and they are mixed intimately. While the mixture is cooled, it is extruded from the mouth piece having a plurality of fine bores to a low pressure zone to obtain stringlike foamed bodies, and then they are cut into foamed fine particles. Then the foamed particles are loaded into molds that can be closed but not be firmly sealed, and are heated to cause the foamed particles to be welded to each other, so that a foamed and molded item in conformity with the molds is obtained. It is preferable that the polypropylene type resin is a propylene/ethylene random copolymer containing 20wt% of ethylene.