Influence of manufacturing on dielectric performance of nanocomposites

Nanodielectrics show remarkable dielectric properties like dielectric breakdown strength, or both surprisingly low and high values for the relative permittivity. These changes compared to materials filled with conventional, microscale filler are often attributed to the high surface area of nanoparticles and their aspect ratio. The even dispersion and distribution of particles in a polymer host is also very important for the dielectric performance of nanocomposites. The influence of the manufacturing and synthesis process on the other hand is often neglected or omitted. Even for the same combination of base materials, the resulting dielectric properties can vary to a great extent. This partly explains large differences encountered in literature regarding dielectric properties of nanocomposites. Focus of this paper is to illustrate the influence that the synthesis process has, not only on dispersion and distribution of particles, but also the structure of a polymer host like epoxy. Examples include nanocomposites based on bisphenol-A epoxy resin with different filler materials.