Effects of the composition ratio, eosin addition, and γ irradiation on the dielectric properties of poly(vinyl alcohol)/glycogen blends

Autor: S. A. Gaafar, M.F.H. Abd El-Kader, S. I. Bannan, F. H. Abd El-Kader, Khaled Mahmoud
Rok vydání: 2008
Předmět:
Zdroj: Journal of Applied Polymer Science. 110:1281-1288
ISSN: 1097-4628
0021-8995
DOI: 10.1002/app.28566
Popis: The dielectric relaxation spectra of various poly(vinyl alcohol) (PVA)/glycogen blends and irradiated blend samples with 70 wt % PVA content that were undoped and doped with eosin were measured in extended temperature (30–160°C) and frequency (1 kHz to 1 MHz) ranges. Dielectric relaxation spectroscopy separates different molecular groups of a repeating unit of a polymer with respect to the rate of its orientation dynamics. In the high-temperature range (>100°C), the σ relaxation, which is associated with the hopping motion of ions in the disordered structure of the biopolymeric material, can be measured. The electric dipole moment and the activation energy of the glass-transition temperature relaxation process were calculated. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Databáze: OpenAIRE