Preparation and properties studies of paraffin/high density polyethylene composites and phase-change coatings

The form-stable paraffin/high density polyethylene (HDPE) composites and phase-change coatings were prepared and characterized in this study. The paraffin acts as thermal absorbing material and HDPE serves as the supporting material, which provides structural strength and prevents the leakage of melted paraffin. Scanning electronic microscope (SEM) showed that the paraffin is dispersed uniformly into porous network of HDPE. Differential scanning calorimeter (DSC) determined the melting temperature and heat storage capacity of the composite piece to be 49.6 °C and 150.88 kJ/kg, respectively. Moreover, results indicated that the composite pieces showed better thermal stability than composite powders after 6 temperature cycling experiments. The phase-change coatings with 40 wt% composites as functional filler showed good adhesion strength and shock resistance, and could decrease the surface temperature obviously comparing with nude Al alloy plates.