Electrical characteristics of different concentration of silica nanoparticles embedded in epoxy resin

Abstract In this study, modified epoxy nanocomposite was produced by incorporating SiO 2 nanoparticles of 15–30 nm in size, with different concentrations ranging from 1 to 20 wt%. The electrical properties of the epoxy nanocomposite were measured at room temperature in the frequency range of 10 −2 –10 7 Hz. To determine the impact of nanoparticles on the epoxy composition, scanning electron microscopy-energy dispersive x-ray spectroscopy (SEM-EDS), Fourier transform infrared spectra (FTIR) spectroscopy, and Raman spectroscopy were conducted. With an increase in filler (SiO 2 nanoparticles) content, the electrical characteristics of the epoxy nanocomposite exhibited multiple changes. At low concentrations, all electrical properties experienced a notable increase. The epoxy with 15 wt% of SiO 2 nanoparticles samples had a lower permittivity, loss number, conductivity, and capacitance than the unfilled epoxy. At medium concentrations (5 to 15 wt%), the formation of immobilized nanolayers has an impact on permittivity, loss number, conductivity, and capacitance, which have decreased; impedance and modulus increased. The initiation of contact between the nanofillers at a concentration of 20 wt% leads to the formation of continuous interfacial conductive pathways, resulting in a dramatic increase in the permittivity, conductivity, and capacitance of the composites, while concurrently reducing impedance.