Enhanced Dielectric Properties of Al/Carbon Black/Epoxy Composites

Polymeric composites with dielectric permittivity but low dissipation factor have wide important applications in modern electronics. In this study, three-phase composites consisting of epoxy, Aluminum (Al) particles and carbon black (CB) were prepared. The morphological and dielectric properties of the composites were investigated using a scanning electron microscope and a dielectric analyzer. The results indicate that the addition of 6 wt% CB remarkably improved the dielectric constant of Al/epoxy composites, and that the dielectric loss of the composites still remained at relatively low levels in a wider frequency range from 10(-1) Hz to 10(7) Hz. Furthermore, with a decrease in the weight ratio CB of to Al, the dissipation factors and electric conductivity of the three-phase composites decreased due to the improved dispersion of CB particles in the Al/PVDF owing to the isolation effect of Al on the CB particles, whereas, the dielectric permittivity increased.