Structure and dielectric properties of polyethylene nanocomposites containing calcined zirconia

The current work investigates the effects of filler calcination on the structure and dielectric properties of polyethylene/zirconia (ZrO
₂
) nanocomposites. Calcination temperatures of 600 and 900 °C have been applied to ZrO
₂
in an attempt to modify its surface chemistry and structure. Calcination results in a slight reduction in the concentration of physically adsorbed water on ZrO
₂
and, in addition, structural reorganization of the ZrO
₂
nanopowder. Consequently, the real permittivity of nanocomposites containing calcined ZrO
₂
is reduced compared to nanocomposites containing uncalcined ZrO
₂
. Furthermore, the DC breakdown strength of nanocomposites containing calcined ZrO
₂
improves compared to nanocomposites containing uncalcined ZrO
₂
. Since the removed water content is minimal, we primarily attribute the observed dielectric results to structural changes in ZrO
₂
rather than water-related effects. As such, calcining can have positive effects in enhancing the dielectric properties of ZrO
₂
-based nanocomposites.