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Updated: May 10, 2026

Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization
Published on: November 27, 2015
Synthesis, characterization, and heterobimetallic cooperation in a titanium-chromium catalyst for highly branched
Shaofeng Liu1, Alessandro Motta, Massimiliano Delferro
1Department of Chemistry, Northwestern University, Evanston, Illinois 60208-3113, USA.
Abstract:
A heterobimetallic catalyst, {Ti--Cr}, consisting of a constrained-geometry titanium olefin polymerization center (CGC(Et)Ti) covalently linked to a chromium bis(thioether)amine ethylene trimerization center (SNSCr) was synthesized and fully characterized. In ethylene homopolymerizations it affords linear low-density polyethylene with molecular weights as high as 460 kg·mol(-1) and exclusively n-butyl branches in conversion-insensitive densities of ~18 branches/1000 carbon atoms, which are ~17 and ~3 times (conversion-dependent), respectively, those achieved by tandem mononuclear CGC(Et)Ti and SNSCr catalysts under identical reaction conditions.
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