摘要 |
Disclosed herein are procatalyst compositions, catalyst compositions and polymers, i.e., propylene-based polymers, produced therefrom. The present procatalyst compositions contain a halo-malonate and a 2-fluoro-malonate in particular. The present catalyst compositions improve catalyst selectivity, improve catalyst activity, and also improve hydrogen response during polymerization. Propylene-based polymer produced from the present catalyst composition has a melt flow rate greater than 50 g/10 min. |