Patent ID: 6207775
Filing Date: 2001-03-27
Classification: C08F

Abstract:
A process for the preparation of a filled polymer composite comprising 1 to 98 percent by weight of an interpolymer and 2 to 99 percent by weight of a filler, said process comprisingpolymerizing ethylene or propylene and at least one comonomer in the presence of a cyclopentadienyl-containing transition metal catalyst and a filler having immobilized thereon an aluminoxane, or a mixture of aluminoxanes,the immobilization of the aluminoxane, which takes place prior to copolymerization, comprising subjecting the cocatalyst treated filler to a heat treatment at a temperature in the range of from 50.degree. C. to 250.degree. C.,in which filler the aluminum present in the aluminoxane is not more than 10 percent by weight extractable in a one-hour extraction with toluene at a temperature of 90.degree. C., using 10 mL toluene per gram of treated filler,under conditions to allow copolymerization of ethylene or propylene and at least one comonomer to form said composite.