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Updated: Mar 15, 2026

Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization
Published on: November 27, 2015
Molecular weight control in organochromium olefin polymerization catalysis by hemilabile ligand-metal interactions
Stefan Mark1, Hubert Wadepohl1, Markus Enders1
1Anorganisch-Chemisches Institut, Heidelberg University, Im Neuenheimer Feld 270, D-69120 Heidelberg, Germany.
Abstract:
A series of Cr(III) complexes based on quinoline-cyclopentadienyl ligands with additional hemilabile side arms were prepared and used as single-site catalyst precursors for ethylene polymerization. The additional donor functions interact with the metal centers only after activation with the co-catalyst. Evidence for this comes from DFT-calculations and from the differing behavior of the complexes in ethylene polymerization. All complexes investigated show very high catalytic activity and the additional side arm minimizes chain-transfer reactions, leading to increase of molecular weights of the resulting polymers.
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