Effect of Internal Donors in Propylene Polymerization Analyzed with NMR and the Internet

摘要

The two-site model was applied to obtain stochastic parameters for MgCl_2/internal donor/TiCl_4 solid catalyst component used in combination with Al(C_2H_5)_3 and external donor for propylene polymerization. The type and the amount of internal donor were varied. With respect to the fraction for asymmetric site, the two-site model enabled us to conclude that new kinds of active centers are generated in specific cases where external donor is believed to be replacing weaker internal donor during polymerization.