Patent ID: 6255247
Filing Date: 2001-07-03
Classification: C08F

Abstract:
A catalyst for the polymerization of propylene monomer to a polypropylene product wherein the xylene solubles are minimized, said catalyst comprising:a) a conventional supported Ziegler-Natta transition metal compound catalyst component for the polymerization of propylene having the general formula MR.sup.+.sub.x where M is a Group IVB metal, R.sup.+ is selected from the group consisting of a halogen and a hydrocarbyloxy, R.sup.+ being the same or different with at least one R.sup.+ being a halogen, and x is the valence of the metal;b) an aluminum trialkyl co-catalyst described by the formula AlR'.sub.3 where R' is an alkyl of from 1-8 carbon atoms and R' may be the same or different; andc) cyclohexylmethyldimethoxylsilane as an external electron donor;wherein the molar ratio of co-catalyst to external electron donor is 2.