Patent ID: 7309678
Filing Date: 2007-12-18
Classification: C08F,Y02P,Y10S

Abstract:
1. A process for the preparation of a supported metallocene catalyst, comprising: (a) providing a particulate catalyst support material in the form of generally spheroidal polyamide particles having an average particle size within the range of 5-60 microns; (b) contacting said particulate polyamide support material with an alumoxane co-catalyst in an aromatic hydrocarbon solvent under conditions in which said alumoxane and said polyamide react with a preponderance of said alumoxane being retained on said polyamide support; (c) recovering said alumoxane containing polyamide support particles from said hydrocarbon solvent; (d) providing a dispersion in an aromatic hydrocarbon solvent of a stereospecific metallocene incorporating a metallocene ligand structure having two sterically dissimilar cyclopentadienyl ring structures coordinated with a central transition metal atom; at least one of said cyclopentadienyl ring structures being a substituted cyclopentadienyl group which provides an orientation with respect to said transition metal atom, which is sterically different from the orientation of the other cyclopentadienyl group with respect to said transition metal atom, and both of said cyclopentadienyl groups being in a relationship with each other providing a stereorigid relationship relative to said coordinating transition metal atom to prevent rotation of said ring structures; (e) mixing said metallocene solvent dispersion and the product produced by the reaction of said particulate catalyst support material and alumoxane for a period of time to allow said metallocene to become reactively supported on said particulate support to form a supported catalyst; and (f) recovering said supported catalyst from said aromatic solvent.