| abstract |
A process for preparing a polyolefin by homopolymerizing or copolymerizing an olefin or olefins using a catalyst comprising a solid catalyst component and an organometallic compound, said solid catalyst component being obtained by contacting at least a titanium compound and/or a vanadium compound with a solid material (a), said solid material (a) being obtained by contacting the following components (1), (2) and (3) with one another:n (1) a silicon oxide and/or an aluminum oxide, (2) a magnesium halide, and (3) an organometallic compound. |