Patent ID: 7405176

Claim:
A main catalyst component for ethylene polymerization, having a general formula: [(MgRX) y (MgX 2 )] a [Ti(OR 2 ) m Cl 4−m ] b (ED) c [R 3 n AlCl 3−n ] e .jSiO 2 , wherein the magnesium compound having a rational formula of (RMgX) y (MgX 2 ), as a component of the main catalyst component, is a magnesium compound in the nascent state prepared by reacting powdered magnesium with an alkyl halide of formula RX in a hydrocarbon solvent and wherein R is an alkyl group having from 3 to 12 carbon atoms, R 2 is an alkyl group having from 1 to 4 carbon atoms, R 3 is an alkyl group having from 1 to 14 carbon atoms, X is halogen, m is from 0 to 4, n is from 1 to 3, SiO 2 is fumed silica, y=0.02 to 1, a=1.96 to 6.0, b=1, e=0.5 to 5.0, j=2 to 60, and y, a, b, e, and j is mole number of individual components, ED is electron donor, and c represents percentage by weight of residual electron donor in the main catalyst component, and is in the range of from 15 to 35 percent by weight, based on the total weight of the main catalyst component.