Catalyst system for the polymerization of olefins

摘要

An organometallic compound obtainable by contacting a) a compound having the following formula (I): wherein Ra, Rb, Rc and Rd equal to or different from each other are hydrocarbon groups b) a Lewis acid of formula (II)MtR13 (II)wherein Mt is a metal belonging to Group 13 of the Periodic Table of the Elements (IUPAC); R1, equal to or different from each other, are selected from the group consisting of halogen, halogenated C6-C20 aryl and halogenated C7-C20 alkylaryl groups; two R1 groups can also form with the metal Mt one condensed ring. These compounds are useful as cocatalysts for polymerizing olefins.