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Silica‐Supported Pentamethylcyclopentadienyl Ytterbium(II) and Samarium(II) Sites: Ultrahigh Molecular Weight Polyethylene without Co‐Catalyst |
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| Authors: | Florian Allouche Ka Wing Chan Dr Alexey Fedorov Prof Dr Richard A Andersen Prof Dr Christophe Copéret |
| Institution: | 1. Department of Chemistry and Applied Biosciences, ETH Zürich, Zürich, Switzerland;2. Department of Chemistry, University of California, Berkeley, CA, USA |
| Abstract: | Designing highly active supported ethylene polymerization catalysts that do not require a co‐catalyst to generate electrophilic metal alkyl species is still a challenge despite its industrial relevance. Described herein is the synthesis and characterization of well‐defined silica‐supported cyclopentadienyl LnII sites (Ln=Yb and Sm) of general formula (≡SiO)LnCp*]. These well‐defined surface species are highly activite towards ethylene polymerization in the absence of added co‐catalyst. Initiation is proposed to occur by single electron transfer. |
| Keywords: | catalysis electron transfer ethylene polymerization lanthanocenes surface chemistry |