CROSSLINKING OF POLYOLEFIN

PURPOSE:To increase degree of crosslinking and rate of extrusion molding, and to obtain a crosslinked product such as covered electric wire, etc. having improved appearance, by feeding a polyolefin to an extruder into which a solution containing a radical generating agent is introduced, bringing the prepared extruded molded article into contact with a condensation catalyst. CONSTITUTION:A polyolefin (pellet) (e.g., polyethylene, ethylene-vinyl acetate copolymer, etc.) is fed from a hopper to an extruder, and, if necessary, the material is dried by the hopper part, a solution obtained by dissolving a radical generating agent (e.g., dicumyl peroxide, dimethyl azoisobutylate, etc.) in a silane compound (e.g., vinyltrimethoxysilane, etc.) is introduced into the extruder. While a heat reaction is carried out in the extruder, the reaction product alone is subjected to extrusion molding, or the polyolefin is applied to the surface of a conductive material by extrusion molding, the prepared extruded molded article is brought into contact with a siloxane condensation catalyst (e.g., dibutyltin dilaurate, etc.) and water, and the polyolefin is crosslinked.