PRODUCTION OF CROSSLINKED MOLDED FOAM

摘要

PURPOSE:A foaming agent is added to a molten silicone-grafted polyolefin at an intermediate point of the extruder under pressure to produce title molded products with uniform and high-extent foam. CONSTITUTION:A silicone-grafted polyolefin is charged in hopper 2 of main extruder 1 and molten by heating to, e.g., 200 deg.C. Succeedingly, a master batch containing a foaming agent is added to a part near head 4 of cylinder 3 by subextruder 5 and the resin is extruded under foaming from head 4 on electrically conductive material 6 to produce insulating wire 8 covered with foam.