Distribution of Al2O3 in PE/EVA blends and the thermal conductivity of PE/EVA/Al2O3 composites

This paper aims at dispersing nanoscale Aluminium oxide (Al2O3) in Polyethylene/Ethylene Vinyl Acetate copolymer blends (PE/EVA) to improve the thermal conductivity of the composites. Blends of PE and EVA were prepared at different PE/EVA ratio, and PE/EVA blends with co-continuous structure were obtained. PE/EVA/Al2O3 composites were prepared by dispersing different amount of Al2O3 into co-continuous PE/EVA blends. Scanning Electron Microscopy (SEM) was used to observe the morphology of PE/EVA/Al2O3 composites treated by selective solution extraction. The thermal conductivities and mechanical properties of PE/EVA/Al2O3 composites were investigated. SEM results indicated that Al2O3 was observed to selectively localize in PE phase. Moreover, the selective distribution of Al2O3 and the co-continuous structure of the composites were helpful in improving the thermal conductivity and mechanical properties, leading to a 20.9% increase of thermal conductivity of PE/EVA/Al2O3 composites in comparison to that of PE/Al2O3 composites.