PRODUCTION OF CROSSLINKED POLYOLEFIN INSULATED CABLE

摘要

PURPOSE:To obtain a crosslinked polyolefin insulated cable having high quality and-high characteristics in good productivity by subjecting a polyolefin composition to extrusion coating onto a conductor, crosslinking the polyolefin composition and then heating the crosslinked polyolefin composition in two step under specific conditions. CONSTITUTION:A polyolefin composition having dicumyl peroxide blended as a crosslinking agent is subjected to extrusion coating onto a conductor and crosslinked to form a crosslinked polyolefin insulated coating. Then the crosslinked polyolefin insulated coating is heated at a temperature of <75 deg.C at which secondary decomposition of cumyl alcohol which is primary decomposition product of the above-mentioned dicumyl peroxide and water content in the crosslinked polyolefin insulated coating is reduced to <=100ppm and the coating is heat-dried at 85-95 deg.C to provide the objective insulated cable eliminated in water led to water treeing in a short time without causing lowering of physical properties of cable, deformation of external shape and temporary accumulation of water.