| 摘要 |
The invention covers a supported catalyst system comprising an alumoxane and a metallocene, prepared according to a process comprising the following step: i) impregnating a silica-containing catalyst support having a specific surface area of from 150 to 800 m/g with one or more titanium compounds of the general formula selected from RTi(OR')and (RO)Ti(OR'), wherein R and R' are the same or different and are selected from hydrocarbyl groups containing from 1 to 12 carbon and halogens, and wherein n is 0 to 4, m is 0 to 4 and m+n equals 4, to form a titanated silica-containing catalyst support having a Ti content of at least 0.1 wt.% based on the weight of the Ti-impregnated catalyst support, for preparing polyolefins. |
