| 摘要 |
<p>The present invention relates to an olefin polymerization catalyst obtainable by depositing on a dry inorganic oxide support a monocuclear chromium complex to produce a catalyst precursor and thereafter by thermally activating the said catalyst precursor. The catalyst is characterised in that the mononuclear chromium complex is representable by the general formula: <CHEM> wherein: - the cyclopentadienyl ligand is substituted with 4 or 5 hydrocarbon groups containing 1 to 3 carbon atoms, - x is an integer from 1 to 4, and - L is either a four-or five-substituted cyclopentadienyl ligand, or (CO)3R in which R is H, methyl or ethyl. The catalyst is used for polymerizing olefins, particularly ethylene optionally with C3-C8 alpha-olefins. It produces polyolefins having a relatively high molecular weight and a broad molecular weight distribution.</p> |
