| 摘要 |
The disclosed invention relates to a polymerization process comprising contacting ethylene, and optionally, one or more olefinically unsaturated comonomers, with an active supported Group 3, 4, 5, or 6 metallocene catalyst system having an unsubstituted or substituted fused-ring cyclopentadienyl ligand, preferably indenyl or fluorenyl, and a substituted or unsubstituted cyclopentadienyl ligand under gas-phase or slurry polymerization conditions. The process is suitable for the production of high-density polyethylene homopolymers and copolymers. The benefits to industrial practice are both the ease of preparation and low-cost of the precursor metallocene compound and the commercially feasible polymerization activity levels in stable, low fouling level reactor conditions surprisingly associated with it. Additionally, the polymers made under the invention process conditions have narrow molecular weight distributions, low MI, and low values for MIR. |
