title: Molecular weight control in organochromium olefin polymerization catalysis by hemilabile ligand-metal interactions.
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.
authors: Anorganisch-Chemisches Institut, Heidelberg University, Im Neuenheimer Feld 270, D-69120 Heidelberg, Germany.
authors: Stefan
authors: S
authors: Mark
authors: Anorganisch-Chemisches Institut, Heidelberg University, Im Neuenheimer Feld 270, D-69120 Heidelberg, Germany.
authors: Hubert
authors: H
authors: Wadepohl
authors: Anorganisch-Chemisches Institut, Heidelberg University, Im Neuenheimer Feld 270, D-69120 Heidelberg, Germany.
authors: Markus
authors: M
authors: Enders
keywords: chromium single-site catalysts; olefin polymerization; ultra-high molecular weight polyethylene