| abstract |
Catalyst systems comprising, on the one hand, a catalytic solid based on complexed titanium trichloride and, on the other hand, a nonhalogenated organolauminium activator. When employed in gas phase olefin polymerization processes, these catalyst systems make it possible to manufacture a wide range of homopolymers and copolymers (random and block) with an isotacticity index which can be adjusted to very low values and with excellent pourability, even in the case of copolymers of high comonomer content. In the absence of transfer agents they also make it possible to synthesise polymers of very high molecular masses, with an increased activity. These polymerization processes yield particularly advantageous results in the case of propylene. |