POLYMERIZATION AND COPOLYMERIZATION METHOD OF ETHYLENE

摘要

PURPOSE: A method for polymerizing and copolymerizing ethylene is provided, to obtain an ethylene polymer having a narrow distribution of molecular weight and a high tail of molecular weight with maintaining a large bulk density. CONSTITUTION: Ethylene is polymerized or copolymerized in the presence of a preactivated solid complex titanium catalyst; and an organometallic compound of group II or III and a haloalkane compound. The preactivated solid complex titanium catalyst is prepared by reacting a magnesium halide and an alcohol to prepare a magnesium compound solution; reacting a compound having a phthalic group represented by C6H4-1-£CO2-R|-a-£CO2-R'| (wherein R and R' are identical or different each other and are an alkyl, isoalkyl, t-alkyl, alkenyl or aryl group of C1-C20, and a is 2, 3 or 4), an ester compound having at least one hydroxy group, and a silicon compound having an alkoxy group represented by RnSi(OR')4-n (wherein R and R1 are a hydrocarbon group of C1-C12, and n is an integer of 0-3) with the magnesium compound solution; adding a mixture of a titanium compound and a silicon compound to the reaction mixture to recrystallize the catalyst to prepare a solid complex titanium catalyst; and preactivating the solid complex titanium catalyst with a poly(hydroalkyl aluminum oxide) compound.