Résumé
This paper shows the space charge behavior of LDPE-based nanomaterials containing graphene oxide as a filler. Space charge was evaluated through the pulse electroacoustic technique at 40 kV/mm and two temperatures, i.e. 20 degrees C and 40 degrees C. From experiments a massive bipolar charge injection and accumulation at room temperature is observed in the neat LDPE sample. In particular, a positive charge packet is injected from the anode and crosses quite rapidly the insulation, dominating space charge accumulation in the bulk. Charge packets are totally absent in LDPE-GO nanocomposites, thus leading to a lower space charge accumulation and consequently to a lower electric field distortion. The best space charge behavior is obtained with low filler concentration, i.e. < 0.1 wt%.