Pre-polymerized catalyst components for the polymerization of olefins

摘要

Catalyst components for the preparation of ethylene (co)polymers capable to produce polymers with high bulk density, to avoid the problems of formation of fines and that have a high activity are provided. Said catalyst components are characterized by comprising a non-stereospecific solid catalyst component, comprising a titanium compound and a magnesium dihalide, which is pre-polymerized with an alpha olefin CH₂-CHR¹ wherein R is a C1-C8 alkyl group, to such an extent that the amount of the alpha-olefin pre-polymer is up to 100 g per g of said solid catalyst component.