PREPOLYMERIZED CATALYST COMPONENTS FOR THE POLYMERIZATION OF OLEFINS

摘要

A Prepolymerized catalyst component for the polymerization of olefins comprising a solid catalyst component which comprises Mg, Ti, and chlorine atoms and an electron donor (ID) said prepolymerized catalyst component being characterized by the fact that: - the electron donor (ID) is constituted by at least 80%mol of 1,3 diethers with respect to the total molar amount of electron donor compounds; -the prepolymerized catalyst has a porosity due to pores with diameters up to Ιμιη of less than 0.2 cm3/g; -it contains an amount of ethylene prepolymer of less than 45% with respect to the total weight of prepolymerized catalyst.