PRE-POLYMERIZED CATALYST COMPONENTS FOR THE POLYMERIZATION OF OLEFINS

摘要

A pre-polymerized catalyst component for the polymerization of olefins endowed with high activity and morphological stability comprises (i) a non-stereospecific solid catalyst component comprising Ti, Mg and a halogen and having a porosity, due to pores with radius up to 1 µm, ranging from 0.2 to 0.8 cm 3 /g and (ii) an amount of an ethylene/alpha-olefin block (co)polymer ranging from 0.1 up to 5g per g of said solid catalyst component (i), said pre-polymerized catalyst component being characterized by a mercury porosity due to pores up to 1 µm of less than 70% the mercury porosity value of the said non-stereospecific solid catalyst component (i).