الفهرس 
Introduction and Aim of the WorkOnly 14 pages are availabe for public view
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Abstract
This Their deals with the study of the characterization and physical properties of some polymeric biomedical materials. The polymers used in this study are pure chitosan, pure poly (Vinyl alcohol) (PVA) and their blends. Namely the fourier transform infrared (F.T IR) and Ultra Voilet Absorption Spectroscopy (U.V). Thermally stimulated depolarization current technique used to study the thermal properties, and the dielectric spectroscopy (DS) used to study the electrical properties of the polymers and their blends. Two techniques have been used in this study to characterize the polymers and their blends; namely the fouier transform Infared (FTIR) and UltraVoilet Absorption Spectroscopy (UV). On the other hand, two techniques were used in the present work; to study the physical properties namely the thermally stimulated depolarization current, (TSDC), technique to study the thermal properties, and the dielectric spectroscopy, (DS), to the electrical properties of the polymers and their blends. FT IR and U.V absorption spectra revealed the appearance of some new bonds in the blend, indicating that PVA may attraction In TSDC technique, the peak associated to Tg is attributed to dipolar relaxation. The activation energy and the relaxation time have been evaluated using the intial rise method. Dielectric properties and electrical conductivity have been reported. The vartions of the variation of the dielectric properties with frequency and temperature have been related mainly to two processes. 1 A local relaxation attributed to the presence of hydrogenbonded water appearing at low frequencies. 2 Relaxation process related to space charge depolarization.