KOPS - Das Institutionelle Repositorium der Universität Konstanz

The role of dormant sites in propene polymerization using methylalumoxane activated metallocene catalysts

The role of dormant sites in propene polymerization using methylalumoxane activated metallocene catalysts

Zitieren

Dateien zu dieser Ressource

Prüfsumme: MD5:0dabf68e56eb2542dd612f39b7387a4f

JÜNGLING, Stephan, Rolf MÜLHAUPT, Udo STEHLING, Hans-Herbert BRINTZINGER, David FISCHER, Franz LANGHAUSER, 1995. The role of dormant sites in propene polymerization using methylalumoxane activated metallocene catalysts. In: Macromolecular Symposia. 97(1), pp. 205-216. ISSN 1022-1360. eISSN 1521-3900. Available under: doi: 10.1002/masy.19950970121

@article{Jungling1995dorma-24062, title={The role of dormant sites in propene polymerization using methylalumoxane activated metallocene catalysts}, year={1995}, doi={10.1002/masy.19950970121}, number={1}, volume={97}, issn={1022-1360}, journal={Macromolecular Symposia}, pages={205--216}, author={Jüngling, Stephan and Mülhaupt, Rolf and Stehling, Udo and Brintzinger, Hans-Herbert and Fischer, David and Langhauser, Franz} }

Langhauser, Franz Mülhaupt, Rolf Mülhaupt, Rolf Stehling, Udo 1995 deposit-license Jüngling, Stephan 2013-07-29T07:34:18Z Fischer, David eng Fischer, David Brintzinger, Hans-Herbert Jüngling, Stephan Brintzinger, Hans-Herbert Stehling, Udo The role of dormant sites in propene polymerization using methylalumoxane activated metallocene catalysts Macromolecular Symposia ; 97 (1995), 1. - S. 205-216 Propene polymerization of methylalumoxane (MAO) activated rac-Me<sub>2</sub>Si(Benz[e]Indenyl)<sub>2</sub>ZrCl<sub>2</sub> (BI) and rac-Me<sub>2</sub>Si(2-Me-Benz[e]Indenyl)<sub>2</sub>ZrCl<sub>2</sub> (MBI) was studied to investigate the influence of the ligand substitution pattern and the role of dormant sites. Poly(propene) end group composition as well as regio- and stereoirregularities were examined by means of <sup>1</sup>H- and <sup>13</sup>C-NMR spectroscopy. Dormant sites, resulting from 2, 1-propene insertion, were reactivated either by β-hydrogen transfer to propene, yielding 2-butenyl end groups, or by 1, 2-insertion of propene, yielding regioirregularities. Propene polymerization in the presence of hydrogen gave n-butyl end groups and less regioirregularities as expected for hydrogenolysis of such dormant sites. Methyl substitution in 2-position of the benz[e]indenyl ligand suppressed β-hydrogen transfer to propene, and increased molecular weight with increasing propene concentration. Also, activation energy increased from 30 kJ/mol (BI/MAO) to 59 kJ/mol (MBI/MAO). For both catalysts activity depended on propene concentration. The order of reaction relative to propene was 1.7. Langhauser, Franz 2013-07-29T07:34:18Z

Dateiabrufe seit 01.10.2014 (Informationen über die Zugriffsstatistik)

Juengling_240629.pdf 177

Das Dokument erscheint in:

KOPS Suche


Stöbern

Mein Benutzerkonto