POLYMERIZATION AND COPOLYMERIZATION METHOD OF ETHYLENE USING CATALYST CHELATED WITH CYCLOPENTADIENE-BASED LIGAND AND CARBODIIMIDE-BASED LIGAND

摘要

PURPOSE: A method for polymerizing and copolymerizing ethylene by using a catalyst chelated with a cyclopentadiene-based ligand and a carbodiimide-based ligand is provided, to enable ethylene to be (co)polymerized by using only generally-used cocatalyst components and to obtain an ethylene polymer or copolymer having a narrow distribution of molecular weight and a uniform distribution of copolymer composition. CONSTITUTION: The method comprises the step of polymerizing or copolymerizing ethylene in the presence of a catalyst component of a transition metal compound of group IV chelated with a cyclopentadiene-based ligand and a carbodiimide-based ligand, and an organometallic compound cocatalyst of group II or III. The catalyst component of a transition metal compound of group IV chelated with a cyclopentadiene-based ligand and a carbodiimide-based ligand, is prepared by reacting a Grignard compound of dialkyl magnesium with an alkoxy aluminium to obtain an alkoxy aluminium-magnesium compound; reacting the obtained alkoxy aluminium-magnesium compound with a cyclopentadiene-based ligand and reacting the obtained one with a carbodiimide-based ligand; and reacting the obtained one with a transition metal of group IV. Preferably the cyclopentadiene-based ligand is represented by C5H(5-x)Rx, wherein R is an alkyl group, an alkenyl group, a phenyl group or a heteroatom-containing alkyl group, and X is an integer of 0-5; and the carbodiimide-based ligand is represented by the formula 1, wherein W, Y and Z are independently an alkyl group, a phenyl group or a heteroatom-containing alkyl group.