POLYETHYLENE HAVING IMPROVED RATE OF CRYSTALLIZATION

摘要

PURPOSE:To provide the titled PE which has a high rate of crystallization and gives moldings having well-balanced properties between rigidity and resistance to environmental stress-cracking, by melt-kneading a specified PE and an org. crosslinking agent to reduce the melt flow rate. CONSTITUTION:An org. crosslinking agent (e.g. dicumyl peroxide) having a decomposition temp. of 95-135 deg.C in a half-life period of 10hr is blended with a high-density PE contg. 5-60wt% linear PE having a density of 0.890-0.935 and a melt flow rate of 0.0005-2g/10min under a load of 20kg obtd. by copolymerizing ethylene with 0.1-10wt% C3-C10 alpha-olefin or linear low-density PE having a density of 0.905-0.935g/cm<3> obtd. by copolymerizing ethylene with C3-C20 alpha- olefin. The mixture is melt-kneaded at 160-300 deg.C in a nitrogen atmosphere to bring about a decrease in the melt flow rate of PE of 5-95%.