Dielectric properties of UV-cured epoxy films treated with Layer-by-Layer nanosilica architectures

This paper focuses on the preparation and characterization of hybrid organic-inorganic epoxy systems obtained through the application of a Layer by Layer (LbL) assembly on a UV-cured epoxy coating. To this aim, a mixture 90/10 (wt.%) of 3,4-epoxycyclohexylmethyl-3\´,4"-epoxy-cyclo-hexane carboxylate (CE)/diglycidylether-terminated polydi-methyl-siloxane (GTPDMS) was subjected to LbL deposition of 10 and 20 bilayers of silica (positively charged/negatively charged). The relationship between the dielectric properties and transition temperature (T_g) were investigated. Two dielectric relaxation modes namely α and β were observed, attributed to the molecular motions of the polymer chains. The breakdown voltage decreased with increasing number of nanosilica bilayers deposited.