Patent ID: 7759445
Filing Date: 2010-07-20
Classification: C08F

Abstract:
1. A process for preparing an olefin polymer by (co)polymerization of ethylene or ethylene with up to 10% by weight, based on the total amount of monomers, of a 1-olefin of formula R—CH═CH 2 , wherein R is an unbranched or branched alkyl radical comprising from 1 to 12 carbon atoms, in suspension, in solution, or in gas phase at a temperature from 20 to 120° C., and a pressure from 0.2 to 6.0 MPa in presence of a catalyst comprising a reaction product of a magnesium alkoxide with a tetravalent transition metal compound, wherein a magnesium alkoxide of formula I wherein R R n is an integer from 2 to 6; is suspended or dispersed as gel in an inert solvent, and is reacted with a tetravalent transition metal compound of formula II wherein M R X is a halogen atom; and m is an integer from zero to 4; at a temperature ranging from 20 to 140° C. in a molar ratio of Mg:M 1 of 1:0.05-10; the reaction product is then after-treated thermally at a temperature ranging from 90 to 200° C. for a period from 10 to 180 minutes, and wherein the catalyst provides in a single stage polymerization process producing a polymer comprising a medium to broad molar mass distribution, expressed as a M w /M n greater than 6.9.