Dielectric relaxation in concentrated solutions of poly(γ‐benzyl‐L‐glutamate)
作者:
Keiichiro Adachi,
Yumiko Hirose,
Yoichi Ishida,
期刊:
Journal of Polymer Science: Polymer Physics Edition
(WILEY Available online 1975)
卷期:
Volume 13,
issue 4
页码: 737-752
ISSN:0098-1273
年代: 1975
DOI:10.1002/pol.1975.180130407
出版商: John Wiley&Sons, Inc.
数据来源: WILEY
摘要:
AbstractMeasurements of dielectric constant and loss, broad‐line nuclear magnetic resonance, and differential thermal analysis of concentrated solutions of poly(γ‐benzyl‐L‐glutamate) (PBLG) were carried out to determine the effects of intermolecular interactions on the mobility of the side group and the solvent (dichloromethane or dioxane). Only one dielectric loss peak due to the cooperative motion of the side group and the solvent was found. The activation energy of this relaxation process varied from 3 to 47 kcal/mole with increasing concentration of PBLG from 20 to 100% by weight accompanied with steep increases at about 40 and 80%. This result is explained as due to entanglement of neighboring side groups. In NMR, narrowing of the line was observed near the temperature where the dielectric loss was observed. The glass transition was also observed by differential thermal analysis. From these results it was concluded that the relaxation observed in PBLG solution and in pure PBLG have the nature of primary or α re
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