| abstract |
A supported catalyst for the polymerization and copolymerization of olefinically unsaturated compounds is described, comprising an organometallic compound of aluminium and a second component obtained by bringing a titanium, vanadium or chromium compound, at least one compound of a second metal chosen from V, Al, Zr, Hf, Mo and Nd and optionally a magnesium compound into contact with a porous support consisting of microbeads of aerogels of one or more inorganic oxides distinguished by low density, high porosity and the fact that at least 90% of the pores have a diameter lying within a very narrow range of values. The process for the polymerization or copolymerization of olefinically unsaturated compounds based on the use of said catalyst is also described. |