| 摘要 |
Process for polymerizing alpha-olefins employing a pretreated catalyst comprising an organopolylithiumaluminum compound prepared by reacting lithium compounds selected from the group consisting of lithium hydride and lithium alkyl with at least one aluminum compound selected from the group consisting of aluminum trialkyl and dialkyl aluminum hydride, an alkyl compound selected from the group consisting of lithium alkyl, aluminum trialkyl and dialkyl aluminum hydride and the alpha form of TiCl3. This catalyst is pretreated by initially polymerizing alpha-olefins with the catalyst under slurry polymerization conditions to form a small amount of prepolymer. The catalyst and small amount of prepolymer is then used to polymerize alpha-olefins subsequently under solution conditions in solution commercial polymerization processes operated at temperatures above 140 DEG C. over extended periods of time. This pretreatment increases the activity of the catalyst, as well as the amount of crystalline polymer obtained.
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