| 摘要 |
<p>Process for the polymerisation of alpha-olefins, carried out in the presence of a catalyst system comprising: (1) a solid based on complexed titanium trichloride, (2) an organometallic compound of metals of groups IA, IIA, IIB and IIIB of the Periodic Table, (3) an electron-donating organic compound, the solid (1) based on complexed titanium trichloride having been preactivated by being placed in contact with a preactivator comprising the product of reaction of an organoaluminium compound (a) and of a compound (b) chosen from hydroxyaromatic compounds whose hydroxyl group is sterically blocked. This process enables propylene to be polymerised with an improved stereospecificity without significant decrease in the catalyst activity.</p> |
