PRODUCTION OF POLYETHYLENE OR POLYPROPYLENE

摘要

PROBLEM TO BE SOLVED: To provide a method for producing polyethylene or polypropylene controlled in the component ratio of atactic/isotatic of the polypropylene. SOLUTION: This method for producing a polyethylene or an isotactic polypropylene or a polypropylene consisting of a mixture of an atactic polypropylene and an isotactic polypropylene comprises a process bringing ethylene or propyelene itself, or a mixture of ethylene or propylene, and one or more kinds ofα-olefins into contact with a preliminary catalyst containing a mixture of a racemic stereoisomer and a meso stereoisomer of a metallocene catalyst, and a cocatalyst selected from a group consisting of tris(perfluorophenyl)borane and isobutylalumoxane or a cocatalyst selected from a group consisting of dimethylanilinium tetrakis(perfluorophenyl)borate and triphenylmethyl tetrakis(perfluorophenyl)borate under polymerization conditions.