composite materials silica / titanium - silicalite in spherical and process to obtain them

摘要

complex metallocenici of metal m selected from among titanium, zirconium and hafnium, comprising at least an anionic group containing a ring? 5 - ciclopentadienilico coordinated to the metal mwhen said group anion is replaced in at least one position of the ring ciclopentadienilico with a radical of formula: (formula i) in which: r6 and r7 are independently hydrogen,halogen or a c1 - c4 alchilico group, preferably hydrogen, n is 0 or 1, preferably 1.and ph * is a group comprising an aromatic ring system (14c connected to - cr6r7 - or and replaced with at least one, and up to a maximum of three groups, electron attractors, with the proviso that,when a is a group? 5 - indenile and n is 0, at least one group ph * is linked to the position 1 or 3 of indenile.these complexes are used in the process of polymerization of the (co)? - olefins, possibly in the presence of a suitable co catalyst.for obtaining high molecular weight polyolefin, to.