Patent ID: 6184316
Filing Date: 2001-02-06
Classification: C07F,C08F

Abstract:
A catalyst for the polymerization of vinylaromatic monomers, comprising the product obtained by contacting with each other the following two components (A) and (B):(A) an .eta..sup.5 -cyclopentadienyl complex of titanium;(B) an organo-oxygenated compound of aluminum;wherein said catalyst contains at least one carboxylate having the following formula:R--COO--G (I)wherein R--COO is a carboxylic group comprising the organic radical R having from 1 to 30 carbon atoms, and G independently represents hydrogen or a metal atom,wherein said .eta..sup.5 -cyclopentadienyl titanium complex has the following formula (II): ##STR3##wherein:Ti is a titanium atom in oxidation state +3 or +4;A is an anion containing an .eta..sup.5 -cyclopentadienyl ring co-ordinated to the titanium atom;each of the R' substituents and R"" independently represents a substituent group selected from hydride, halide, a C.sub.1 -C.sub.8 alkyl group, a C.sub.3 -C.sub.12 alkylsilyl group, a C.sub.5 -C.sub.8 cycloalkyl group, a C.sub.6 -C.sub.10 aryl group, a C.sub.1 -C.sub.8 alkoxy group, a C.sub.1 -C.sub.30 carboxylic group, and a C.sub.2 -C.sub.10 dialkylamide group;or R"" represents a second anion containing an .eta..sup.5 -cyclopentadienyl ring co-ordinated to the titanium, and may also be covalently bound to A by means of a divalent bridged group, so as to form a cyclic structure comprising at least 4 atoms, one of which is the titanium atom,""n"" is equal to 1 or 2 respectively when the titanium is in oxidation state +3 or +4.