High-k nanocomposites with modified double layer in carbon black-epoxy system

High dielectric constant (K), low dielectric loss (tan δ) polymer nanocomposite is achieved by introducing a modified electrical double layer in the carbon black (CB)-epoxy system, rather than by exploiting the percolation of CB in the epoxy system, in which both the dielectric constant and loss are increased simultaneously. The modified electrical double layer is introduced in CB-epoxy system when nanosized nickel oxides embedded in CB absorbs anionic surfactants. In addition to the ionic charges on the CB, high-k and low dielectric loss can be obtained because of CB passivation with the polymeric surfactant. The CB-epoxy nanocomposite containing 3.1 vol% of modified CB exhibited a high dielectric constant of K 5200 and a low dielectric loss of tan δ 45% at 1 MHz.