Dataset for: The effects of water on the dielectric properties of aluminum based nanocomposites

This dataset should be used in conjunction with the journal publication;"The effects of water on the dielectric properties of aluminum based nanocomposites"Authors: Ian L Hosier, Matthew Praeger, Alun S. Vaughan and Steve G Swingler in: IEEE Transactions on Nanotechnology, Vol. 16, no. 4, pp. 1-10, July 2017The excel file contains the raw data used to generate each figure on a separate tab.Note: The figure ExtraTGAwork.TIF is a graphic of the effects of wet and dry conditioning on water uptake. It is mentioned in the text of the paper but there was insufficient room to include it in the manuscript.Abstract: A series of polyethylene nanocomposites was prepared utilizing aluminum nitride or alumina nano-powders with comparable morphologies. These were subsequently subjected to different conditioning regimes, namely prolonged storage in vacuum, the ambient laboratory environment or in water. The effect of filler loading and conditioning (i.e. water content) on their morphological and dielectric properties was then examined. Measurements indicated that, in the case of aluminum nitride nanocomposites, none of the conditioning regimes led to significant absorption of water and, as such, neither the dielectric properties nor the DC conductivity varied. Conversely, the alumina nanocomposites were prone to the absorption of an appreciable mass of water, which resulted in them displaying a broad dielectric relaxation, which shifted to higher frequencies, and a higher DC electrical conductivity. We ascribe these different effects to the interfacial surface chemistry present in each system and, in particular, the propensity for hydrogen bonding with water molecules diffusing through the host matrix. Technologically, the use of nanocomposites based upon systems such as aluminum nitride, in place of the commonly used metal oxides (alumina, silica, etc.), eliminates variations in dielectric properties due to absorption of environmental water without resorting to the adoption of techniques such as surface functionalization or calcination in an attempt to render nanoparticle surface chemistry hydrophobic.