| 摘要 |
A catalyst composition for the polymerization of olefins, particularly the copolymerization of ethylene with at least one C3-C7 alpha olefin, comprises a porous crystalline siliceous material containing in catalytically active form 0.05 to 3 weight percent chromium. 1.5 to 9 weight percent titanium and up to 2.5 weight percent fluorine. |
