Microwave Dielectric Relaxation Spectroscopy of Nano Filler Loaded Epoxy Composite

Abstract

Present work reports the result of spectroscopic dielectric relaxation study of (Bisphenol A-(epichlorhydrin): epoxy) and hardener (N(3-dimethylaminopropyl)-1,3-propylenediamine: hardener) doped with a range of concentrations of inorganic nano-fillers (SiO2, Al2O3, TiO2 and ZnO) and their mixtures. Measurements of complex permittivity of neat epoxy (epoxy + hardener), nano-epoxy composite (nano filler + neat epoxy) and mixed-nano epoxy composites (mixed nano filler + neat epoxy) are carried out using vector network analyzer along with SPEAG dielectric assessment kit over the frequency range of 200 MHz to 20 GHz at a constant temperature of 300.15 K. Obtained results are analyzed in order to attain the structural information and polarization mechanisms exhibited in these composites. Influence of varying concentrations of inorganic nano-fillers on the dielectric behavior of neat epoxy is explicitly conferred. From the obtained dielectric properties; other microwave energy parameters like power reflected (Pr), power transmitted (Pt) and penetration depth (dp) are also determined at a spot frequency of 2.45 GHz and examined to gain additive information in view of their specific industrial and medical applications.