Influence of moisture absorption on space charge property of MgO/LDPE nanocomposite

Abstract

In order to understand the change rule and its mechanism for the space charge property of Magnesium oxide (MgO)/ LDPE nanocomposites after damp, the moisture absorption weight and space charge properties of wet LDPE and MgO/LDPE were studied. Experiments results show that moisture absorption has a strong influence on dielectric properties of MgO/LDPE nanocomposite. After nanocomposite had been exposed for a week under the 40% relative humidity conditions, the improved space charge property of the composite at high electric field above 20kV/mm, were decreased obviously compare to dry MgO/LDPE. It is believed that moisture absorption may lead to a weakening of original interfacial charge distribution. On contrary, at low electric field, the MgO/LDPE system showed the strong suppression effect of aditional carriers migration caused by absorbed moisture.