Patent ID: 6221802
Filing Date: 2001-04-24
Classification: C08F,Y10S

Abstract:
A catalyst usable for the polymerization of .alpha.-olefins, including a compound (b) containing at least one metallocene derived from a transition metal belonging to the groups IIIb, IVb, Vb and VIb of the Periodic Table bound in or on a support wherein the support includes at least one .alpha.-olefin polymer which is in the form of particles of mean size from 5 to 350 .mu.m, in which the pore volume generated by the pores of radius from 1,000 to 75,000 .ANG. is at least 0.2 cm.sup.3 /g and which is obtained by polymerization of one or more .alpha.-olefins by means of a catalyst system (S) containing a catalytic compound (a) based on a transition metal belonging to groups IIIb, IVb, Vb and VIb of the Periodic Table and an activator chosen from organoaluminum compounds, said compound (a) being in the form of particles of mean size from 2 to 200 .mu.m, of pore volume generated by the pores of radius from 200 to 15,000 .ANG. of at least 0.02 cm.sup.3 /g, wherein the support contains, per kilogram, from 2 to 170 grams of compound (a).