Resumen

Catalyst component prepd.. by contacting a metallocene cpd. (1) with an inorganic support: where M is a metal of gp. IVb, Vb or VIb; X= 1-10C alkyl, 1-10C alkoxy, 6- 10C aryloxy, 2-10C alkenyl, 7-40C arylalkyl, 7-40C alkylaryl, 8-40C arylalkenyl; L1 & L2 =(substd.) cyclopentadienyl, (substd.) indenyl, (substd.) fluorenyl, R1-R8 =H, 1-10C alkyl, (subst.) 5-7C cycloalkyl; or R6, R8 = Ha, NH2, alkylamino, OH; o,p,q,r,s, =0-10; m=0 or 1, n=1 or 2, h=2 or 3 such that m+n+h=4. The inorganic support contains OH gps. or has been modified by reaction of the OH gps. with cpds. of formula (II) The surface area of said inorganic support =10-1000 (150-650) m2/g, pore volume = 0.2-4 (0.6-2.7) cm3/g, average particle size = 1-1000 (5-100) microns. Also claimed is a catalyst component further comprising a cocatalyst.