The influence of combined external donor and combined cocatalyst on propylene polymerization with a MgCl₂‐supported <scp>Z</scp>iegler–<scp>N</scp>atta catalyst in the presence of hydrogen

Abstract

ABSTRACT The influence of combined external donor (ED) (diphenyldimethoxysilane/dicyclopentyldimethoxysilane) and combined cocatalyst (triethylaluminum/triisobutylaluminum) on propylene polymerization with MgCl 2 ‐supported Ziegler–Natta catalyst in the presence of hydrogen was investigated. By deconvolution analysis of the molecular weight distribution (MWD) into multiple Flory components, the influence of ED and cocatalyst on the active center distribution of the catalyst was demonstrated, and the mechanism was discussed. Using combined cocatalyst and combined donor, iPP with high molecular weight, high isotacticity index, and broad MWD can be obtained. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132 , 41689.