| 摘要 |
The present invention provides a process for preparing a supported metallocene catalyst system that can be used to catalyze formation of polyolefins having a wide molecular weight range. In accordance with the process of the present invention, a first portion of an inorganic oxide is dried under a first set of conditions, wherein upon treatment with an organoaluminoxide and a metallocene, a first catalyst system is formed usable to produce a polyolefin product having a first molecular weight average distribution. A second portion of an inorganic oxide under a second set of conditions, wherein upon treatment with an organoaluminoxane and a metallocene, a second catalyst system is formed usable to produce polyolefin product having a second molecular weight distribution. An amount of the first portion is mixed with an amount of the second portion to produce a final inorganic oxide support. The final inorganic oxide support is combined with an organoaluminoxane and a metallocene to produce a supported metallocene catalyst system usable to catalyze formation of polyolefins with a broadened molecular weight average distribution.In another aspect, the present invention provides a process for polymerizing polyolefins using the inventive supported metallocene catalyst system. The process comprises preparing the final catalyst as mentioned above and then contacting an olefin with the final metallocene catalyst system under conditions supporting polymerization.
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