Study of the PEG content effect on some properties of the PVA/PEG-EY films using the Raman, positron annihilation and impedance spectroscopies

Abstract

PVA/PEG-EY blend structures are synthesized with PEG concentrations of 0, 1, 3, 5, 10, 15 and 20 wt% using casting method. The electrical and dielectric properties of the blend samples were studied with frequency in range (0.1 Hz to 20 MHz), via impedance spectroscopy. The Raman spectroscopy characterized and distinguish the structure of the prepared films. Theoretical results of Raman spectra of PVA, PEG and EY samples were analyzed based on linear response time-dependent density functional theory and then compared with experimental results of the samples. The microstructure and defect distribution of the synthesized samples were inferred using the positron annihilation spectroscopy (PAS). Experimental and theoretical Raman analysis indicates the increase of diffusion of EY and PEG. Broadband dielectric spectroscopy investigation on a broad range of frequencies shows that the enhancement of electrical conductivity of the prepared PVA/PEG-EY film with increasing PEG content. The considerable effect of the PEG content on the film microstructure was approved. The interactions between the PVA and PEG through the formation of hydrogen bonding modify the size and concentration of the free volume holes.