Ultrasonic and dielectric relaxations in PDMS/ZnO nanocomposite

Abstract

In this article, we present the impact of ZnO nanoparticles on ultrasonic and dielectric properties of Polydimethylsiloxane (PDMS)‐based nanocomposites in a wide temperature range. The complex dielectric permittivity was measured as a function of the frequency at various temperatures and it was shown that the magnitude and the position of the dielectric loss peak in the temperature scale depend on the concentration of fillers in PDMS/ZnO composite. The temperature dependences of ultrasonic wave attenuation showed attenuation peaks similar to those obtained by means of the dielectric spectroscopy. These peaks are attributed to the dynamic glass transition and obey the Vogel–Fulcher–Tammann (VFT) equation. Values of the static glass transition temperature obtained analyzing the dielectric and ultrasonic data are consistent and increase with the concentration of ZnO. The ultrasonic wave attenuation and velocity in these composites depend on the filler concentration.