Effect of Carbon Black and Water Absorption on Dielectric behavior of EP-modified SiO2 composites


Epoxy (EP) – Silica (SiO2) composites are well known composites used in microelectronic industry . So it is important to study their dielectric behavior under different conditions such as the presence carbon black (UV absorber) and immersion in the water for 30 days .Dielectric properties were calculated over the frequency range 102 – 106 Hz for epoxy composites with different weight % of micrometer 1.5μm SiO2 particles (60%, 65% and 70wt%) modified with 0.5wt% silane coupling agent to improve adhesion between EP and SiO2 phases . Similar dielectric constant ( ) behavior was observed for all composites , where values decrease slightly with increasing frequency . Dielectric loss behavior shows relaxation peak around 104Hz for composites with and without carbon black . 0.35% weight gain was observed for immersed composites in water and highest relaxation peaks intensity were observed at higher frequency (around 105 Hz) . Recovery study was performed on immersed composites and no chemical changes have taken place .