METALLOCENE CATALYST FOR FORMING POLYETHYLENE, METHOD FOR PRODUCING THE SAME AND POLYMERIZATION PROCESS BY USING THE SAME

摘要

PURPOSE: A metallocene catalyst is provided to efficiently serve as a catalyst for the homo-polymerization of ethylene and/or copolymerization of ethylene and alpha-olefine to prepare high density and linear low density polyethylene products even at high temperature. CONSTITUTION: The metallocene catalyst having any one of the following formulas(1) and (2) comprises a geometrically restraint ligand including heterocyclic ring structural substituent. The catalyst is prepared by firstly reacting compounds of the formulas(3):CpLi and (4):R2R3SiX2 or R2R3CX2 in a mole ratio of 1:0.1-10 at -78 to 200 deg.C and secondly reacting the obtained material with another compound of the formula(5):NH2R in a mole ratio of 1:1-10 a -78 to 200 deg.C to synthesize the geometrical ligand; reacting the ligand with n-BuLi or grignard reagent in a mole ratio of 1:1-10 at -78 to 200 deg.C to form anion type material then reacting it with the compound of formula(6):MClx(6-x)THF in a mole ratio of 1:0.1-10 at -78 to 200 deg.C. Afterward, the produced compound of formula(7):ML4 after recrystallization process of some parts dissolved into diethylether or normal pentane reacts with the compound of formula(6) in 1:1 mole ratio at 0-200 deg.C. After extracting it under vacuum condition, the metallocene catalyst is obtained as the resultant material.