Patent ID: 6437063
Filing Date: 2002-08-20
Classification: C08F,C08L,Y02P,Y10S

Abstract:
A process for producing a propylene polymer nucleated with a polymeric nucleating agent containing vinyl compound units, comprising the steps ofmodifying a catalyst by polymerizing a vinyl compound of the formula â€ƒwherein R1 and R2 together form a 5 or 6 membered saturated or unsaturated or aromatic ring at a weight ratio of the vinyl compound to the catalyst amounting to 0.1 to below 3, in the presence of said catalyst, by carrying out the modification in a medium which does not dissolve the polymerized vinyl compound and by continuing the polymerization of the vinyl compound until the concentration of unreacted vinyl compounds is less than about 0.5 wt-%, to produce a modified catalyst composition, said modification being carried out before any prepolymerization step of the catalyst with an olefinic monomer, and polymerizing propylene optionally together with comonomers in the presence of said modified catalyst composition.