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Factors influencing chain transfer with monomer and with hydrogen in propene polymerization using MgCl2-supported Ziegler-Natta catalysts

2000; Wiley; Volume: 201; Issue: 14 Linguagem: Inglês

10.1002/1521-3935(20000901)201

1521-3935

John C. Chadwick, Johannes J. R. Heere, Olof Sudmeijer,

Machine Learning in Materials Science

Macromolecular Chemistry and PhysicsVolume 201, Issue 14 p. 1846-1852 Research Article Factors influencing chain transfer with monomer and with hydrogen in propene polymerization using MgCl2-supported Ziegler-Natta catalysts John C. Chadwick, John C. Chadwick JC.Chadwick@opc.shell.com Search for more papers by this authorJohannes J. R. Heere, Johannes J. R. Heere Montell Polyolefins B.V., c/o Shell Research and Technology Centre, Amsterdam, P.O. Box 38000, 1030 BN Amsterdam, The NetherlandsSearch for more papers by this authorOlof Sudmeijer, Olof Sudmeijer Montell Polyolefins B.V., c/o Shell Research and Technology Centre, Amsterdam, P.O. Box 38000, 1030 BN Amsterdam, The NetherlandsSearch for more papers by this author John C. Chadwick, John C. Chadwick JC.Chadwick@opc.shell.com Search for more papers by this authorJohannes J. R. Heere, Johannes J. R. Heere Montell Polyolefins B.V., c/o Shell Research and Technology Centre, Amsterdam, P.O. Box 38000, 1030 BN Amsterdam, The NetherlandsSearch for more papers by this authorOlof Sudmeijer, Olof Sudmeijer Montell Polyolefins B.V., c/o Shell Research and Technology Centre, Amsterdam, P.O. Box 38000, 1030 BN Amsterdam, The NetherlandsSearch for more papers by this author First published: 26 September 2000 https://doi.org/10.1002/1521-3935(20000901)201:14 3.0.CO;2-OCitations: 22AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Abstract 13C and 1H NMR analysis of polypropylene prepared using various MgCl2-supported catalysts at different polymerization temperatures at different hydrogen concentrations has revealed that chain transfer with monomer, yielding vinylidene-terminated chains, is essentially unaffected by hydrogen but is dependent on catalyst selectivity. Chain transfer with hydrogen and with monomer are therefore processes which operate independently of each other, but in both cases, the incidence of chain transfer increases with decreasing catalyst (site) selectivity. Chain transfer with monomer takes place after primary insertion, while chain transfer with hydrogen takes place after either primary or secondary insertion. Chain initiation via a secondary insertion into a Ti-H species leads either to a 2,3-dimethylbutyl terminal unit, as has recently been observed in metallocene-catalyzed polymerizations, or to a further transfer reaction with hydrogen, generating traces of propane. Citing Literature Volume201, Issue14September 2000Pages 1846-1852 RelatedInformation