Fluorine- and Trimethylsilyl-Containing Phenoxy−Imine Ti Complex for Highly Syndiotactic Living Polypropylenes with Extremely High Melting Temperatures
- 18 June 2002
- journal article
- research article
- Published by American Chemical Society (ACS) in Journal of the American Chemical Society
- Vol. 124 (27) , 7888-7889
- https://doi.org/10.1021/ja026229r
Abstract
A fluorine- and trimethylsilyl-containing phenoxy-imine titanium complex was synthesized and the structure was determined by an X-ray analysis. The complex on activation with MAO initiates highly controlled syndiospecific living propylene polymerization to form extremely high Tm syndiotactic polypropylenes (Mw/Mn = 1.05−1.08, Tm = 156−152 °C) at 0 or 25 °C. Moreover, at 50 °C, the complex afforded monodisperse syndiotactic polypropylene with very high Tm's of 149, 150 °C. In contrast, complexes having a t-Bu group instead of the silyl group provided lower tacticity polymers with much lower Tm's. In addition, we revealed the substituent effect that plays a key role for the highly controlled syndiospecific polymerization displayed by the catalyst.Keywords
This publication has 13 references indexed in Scilit:
- Highly active ethylene polymerization catalysts based on titanium complexes having two phenoxy-imine chelate ligandsJournal of Molecular Catalysis A: Chemical, 2002
- Microstructure of Highly Syndiotactic “Living” Poly(propylene)s Produced from a Titanium Complex with Chelating Fluorine-Containing Phenoxyimine Ligands (an FI Catalyst)Macromolecular Rapid Communications, 2001
- A Family of Zirconium Complexes Having Two Phenoxy−Imine Chelate Ligands for Olefin PolymerizationJournal of the American Chemical Society, 2001
- Isospecific Living Polymerization of 1-Hexene by a Readily Available Nonmetallocene C2-Symmetrical Zirconium CatalystJournal of the American Chemical Society, 2000
- Synthesis of Group 4 Complexes that Contain the Diamidoamine Ligands, [(2,4,6-Me3C6H2NCH2CH2)2NR]2- ([Mes2N2NR]2-; R = H or CH3), and Polymerization of 1-Hexene by Activated [Mes2N2NR]ZrMe2 ComplexesJournal of the American Chemical Society, 1999
- Group 4 Cs symmetric catalysts and 1-olefin polymerizationJournal of Molecular Catalysis A: Chemical, 1999
- Mechanisms of Stereocontrol for Doubly Silylene-Bridged Cs- and C1-Symmetric Zirconocene Catalysts for Propylene Polymerization. Synthesis and Molecular Structure of Li2[(1,2-Me2Si)2{C5H2-4-(1R,2S,5R-menthyl)}{C5H-3,5-(CHMe2)2)}]·3THF and [(1,2-Me2Si)2{η5-C5H2-4-(1R,2S,5R-menthyl)}{η5-C5H-3,5-(CHMe2)2}]ZrCl2Journal of the American Chemical Society, 1998
- Living Polymerization of α-Olefins by Chelating Diamide Complexes of TitaniumJournal of the American Chemical Society, 1996
- Stereospecific Olefin Polymerization with Chiral Metallocene CatalystsAngewandte Chemie International Edition in English, 1995
- Preparation of (p-vinylbenzyl)poly(2-vinylpyridine) macromersMacromolecules, 1986