Titolo | Methyl dynamics and β-relaxation in polyisobutylene: Comparison between experiment and molecular dynamics simulations |
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Tipo di pubblicazione | Articolo su Rivista peer-reviewed |
Anno di Pubblicazione | 2002 |
Autori | Karatasos, K., Ryckaert J.-P., Ricciardi Rosa, and Lauprêtre F. |
Rivista | Macromolecules |
Volume | 35 |
Paginazione | 1451-1462 |
ISSN | 00249297 |
Parole chiave | Characterization, Computer simulation, Dielectric relaxation spectroscopy, Glass transition, molecular dynamics, neutron scattering, Nuclear magnetic resonance spectroscopy, Organic polymers, Polyisobutylene, Relaxation processes, Spectroscopy, Temperature |
Abstract | Molecular dynamics simulations were employed in bulk polyisobutylene, to provide a detailed characterization of the methyl dynamics and to examine its relation to the β-relaxation as described by different experimental techniques. The simulation results were compared to new 13C NMR measurements probing methyl motion at temperatures above the glass transition, as well as to lower temperature literature NMR data. It was found that the 13C NMR results, and those for the β-relaxation reported by dielectric relaxation spectroscopy and neutron scattering experiments, can be interpreted on a common basis through a coupling mechanism between methyl rotation and a recently described fast relaxation motion associated with the chain backbone. In addition, a molecular mechanism for the description of the dielectric β-process observed in polyisobutylene is proposed, and investigated by simulations. |
Note | cited By 21 |
URL | https://www.scopus.com/inward/record.uri?eid=2-s2.0-0037065905&doi=10.1021%2fma011290m&partnerID=40&md5=784013c3188b51bcb6952d21d5a484d9 |
DOI | 10.1021/ma011290m |
Citation Key | Karatasos20021451 |