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Updated: Apr 16, 2026

Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization
Published on: November 27, 2015
Comonomer-induced stereo-selectivity enhancement in a c2 -symmetric metallocene-catalyzed propylene polymerization
1CAS Key Laboratory of Engineering Plastics, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
Abstract:
Propylene polymerization is carried out with a C 2 -symmetric metallocene catalyst of rac-Et(Ind)2 ZrCl2 /MAO at 40 °C in the presence of a cyclo-triene of trans,trans,cis-1,5,9-cyclododecatriene ((E,E,Z)-CDT). Comonomer incorporations are rather low (<0.10 mol%). However, it is shown for the first time that the comonomer causes a noticeable increase in poly-propylene -isotacticity (>7% in [mmmm]). (E,E,Z)-CDT is speculated to coordinate to the metal center forming comonomer-complexed active sites in charge of the entire polymerization reaction with decreased activity however increased propylene -enantiomorphic selectivity.
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