In this paper we report an investigation into the dielectric responses in the frequency domain from 10{sup}(-2) Hz to 10{sup}6 Hz at the temperature range from -50 to 90°C of nano-alumina filled epoxy composites. The dielectric behaviour has been investigated both before and after an exhaustive drying of both the nano-composite dielectric as well as the nano-alumina powder. The results show that an unusual dielectric behaviour is observed for both nanocomposites and nano-alumina powder before the drying treatment. After drying no unusual dielectric response is observed. This behaviour is related to the location and mobility of water in materials which support a very high internal surface area. The relaxation behaviour is explored and fitted by multiple Havriliak-Negami functions, and the dynamics of interfacial water discussed.
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