Preparation and properties of gypsum based energy storage materials with capric acid-palmitic acid/expanded perlite composite PCM

Phase change materials (PCMs) have been widely applied to develop building materials with high thermal energy storage capacity. In this study, the capric acid-palmitic acid (CA-PA)/expanded perlite (EP) composite PCM was prepared using vacuum impregnation method and the thermal-regulated gypsum boards were fabricated by adding the prepared composite PCM. Scanning electron microscope images revealed that the CA-PA eutectic mixture was uniformly distributed in pores of EP and the CA-PA/EP composite PCM has a little effect on the interface gypsum crystals growth. Differential scanning calorimeter results showed that the melting temperature range of the composite PCM was 24.1-31 °C and the latent heat was 88.39 J g−1. The composite PCM had a good chemical stability by surveying the chemical characterization of the composite PCM. Furthermore, the heat transfer property, thermal conductivity, bending and compressive strength were also tested. The results indicated that the higher the composite PCM volume content, the smaller the thermal conductivity of the gypsum board and the lower the temperature fluctuation in the cubicle system. The bending strength and compressive strength reduced gradually with an increase of the volume fraction of the composite PCM.