abstract |
A catalyst for the polymerization of olefins comprises the product obtained by contacting:n (A) a titanium, zirconium or hafnium mono- or bis-cyclopentadienyl compound, this latter optionally containing a bridging group which links the two cyclopentadienyl compounds; (B) an alkyl aluminium wherein at least one alkyl is different from a straight alkyl; and (C) water. The molar ratio aluminium/water is higher than 1:1 and lower than 100:1. |