摘要 |
A new catalyst component and its use with an organoaluminum compound, which component is a brown solid of high surface area and large pore volume comprising beta titanium trichloride and a small amount of an organic electron pair donor compound. This solid when used in conjunction with an organoaluminum compound to polymerize alpha-olefins produces product polymer at substantially increased rates and yields compared to present commercial, purple titanium trichloride while coproducing reduced amounts of low-molecular-weight and, particularly, amorphous polymer. Combinations of this new catalyst component and an organoaluminum compound can be further improved in their catalytic properties by addition of small amounts of modifiers, alone and in combination. Such combinations with or without modifiers show good sensitivity to hydrogen used as a molecular weight controlling agent. The combinations are useful for slurry, bulk and vapor phase polymerization of alpha-olefins such as propylene. |