Viscosity Dependence of the Local Segmental Dynamics of Anthracene-Labeled 1,2-Polybutadiene in Dilute Solution
Autor: | Koichi Ito, David B. Adolf, M. D. Ediger, Toshiaki Kitano |
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Rok vydání: | 1998 |
Předmět: |
Polymers and Plastics
Chemistry Intrinsic viscosity Relative viscosity Organic Chemistry Inherent viscosity Fluorescence spectrometry Thermodynamics Atmospheric temperature range Inorganic Chemistry Viscosity Polybutadiene Temperature dependence of liquid viscosity Polymer chemistry Materials Chemistry |
Zdroj: | Macromolecules. 31:5794-5799 |
ISSN: | 1520-5835 0024-9297 |
DOI: | 10.1021/ma980386m |
Popis: | Time-correlated single-photon-counting measurements have been performed on anthracene-labeled 1,2-polybutadiene. The local segmental dynamics were observed in seven solvents covering a viscosity range of more than three decades and over the temperature range of 280−350 K. Correlation times were extracted from the fluorescence anisotropy decays and were determined as a function of temperature in all solvents. The observed temperature and viscosity dependence has been examined in terms of Kramers' theory in the high friction limit and two empirical equations, those of Fleming and co-workers and Robinson, both of which incorporate the idea of frequency-dependent friction developed by Grote−Hynes. It was found that the dynamics scaled as the viscosity to the power 0.82 ± 0.04. |
Databáze: | OpenAIRE |
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