Experimental study of dielectric properties of composite materials pozzolan/DGEBA

The subject of composite materials with reinforced filler has been studied recently. This study to improve both the dielectric and structural characteristics of Diglycidyl Ether of Bisphenol A (DGEBA) focused on the appropriate use (from 5% to 60 wt%) of pozzolan filler mechanically grinded to obtain a very fine particle size (O <10μm) and area surface of 23,.5 m 2 .g 1 . The dielectric properties were investigated at great filler concentrations by weight. Epoxy microcomposite samples with a good dispersion of nanoparticles in the epoxy matrix were prepared and experiments were performed to measure the dielectric constants (C), the resistance (R) and impedance (Z) as a function of frequency (1 kHz-10 kHz). Measurements were made using dielectric spectroscopy over the temperature range 25°C80°C.The best dielectric properties correspond to a micro-filler content equal to 30wt%,This is attributed to the large volume fraction of interfaces in the bulk of the material and the barrier between the charged nanoparticle surface and the epoxy chains. Using the scanning electron microscope (SEM), the morphologies and structure of the surface and fracture surfaces of Pozzolan/ DGEBA composites were observed. POLYM. COMPOS., 00:000–000, 2015. ©2015 Society of Plastics Engineers