Patent ID: 6524986
Filing Date: 2003-02-25
Classification: C08F,Y10S

Abstract:
A catalyst usable for the polymerization of &agr;-olefins including a compound (b) containing at least one transition metal containing at least titanium, magnesium and chlorine bound in or on a support wherein the support includes at least one &agr;-olefin polymer which is in the form of particles of mean size from 5 to 350 &mgr;m, in which the pore volume generated by the pores of radius from 1,000 to 75,000 Ã¥ is at least 0.2 cm3/g.,wherein the support is obtained by polymerization of one or more &agr;-olefins by means of a catalyst system (S) containing a catalytic compound (a) based on a transition metal belonging to group IIIb, IVb, Vb, and VIb of the Periodic Table which is in the form of particle of mean size from 2 to 200 &mgr;m, of pore volume generated by the pores of radius from 200 to 15,000 Ã¥ of at least 0.02 cm3/g and contains, per kg, from 2 to 170 g of compound (a), said catalytic system (S) containing further an organoaluminium compound as activator.