| 摘要 |
<p>An improved process of preparing an olefinic polymer of the type in which an olefinic monomer is polymerized alone or with a comonomer in an aromatic hydrocarbon solvent using a metallocene catalyst of formula (I) in the presence of a cocatalyst; wherein the improvement comprises: preparing the olefinic polymer in an aliphatic hydrocarbon solvent using a modified metallocene catalyst which is obtained by introducing at least one C5-20 alkyl substituent into the π-ligand, the alkylene bridge or silicone bridge of the metallocene catalyst of the formula (I): L1L2MX2 wherein M is Ti, Zr or Hf; X is a halogen, or a C1-3 alkyl group; and L?1 and L2¿ are each a π-ligand selected from the group consisting of cyclopentadienyl, indenyl, fluorenyl and derivatives thereof, and are optionally linked together by a C¿1-4? alkylene bridge optionally substituted with a C1-3 hydrocarbyl group or by a silicone bridge optionally substituted with a C1-3 hydrocarbyl group.</p> |
