摘要 |
Disclosed herein are catalyst compositions and polymers, i.e., propylene-based polymers, produced therefrom. The present catalyst compositions contain an internal electron donor of an alkoxyalkyl 2-propenoate and optionally a mixed external electron donor. The present catalyst compositions improve catalyst selectivity and polymer stiffness. Polypropylene homopolymer produced from the present catalyst composition has a xylene solubles content less than 4 wt % and a TMF greater than 172.0° C. |