A novel capric-stearic acid/expanded perlite-based cementitious mortar for thermal energy storage

In this study, capric-stearic acid (CA-SA) was employed as the phase change material (PCM), while expanded perlite (EP) was utilized as the supporting material to prepare CA-SA/EP composite through vacuum impregnation method. According to the leakage experimental results of CA-SA/EP, the ideal weight fraction of CA-SA was found to be 50 %. The micro-morphology, thermal storage properties and reliability of CA-SA/EP were systematically studied. The melting temperature of the CA-SA/EP was measured to be 24.66 °C, while the latent heat value was determined to be 77.90 J/g. To investigate the feasibility of applying CA-SA/EP in energy-saving buildings, it was used as a replacement for sand in the mixed aggregate to prepare CA-SA/EP-based mortar. The results showed that incorporating CA-SA/EP composite into the mortar significantly enhances its thermal properties, while also improving the integrity of CA-SA/EP-based mortars upon failure and exhibiting good plasticity. It is noteworthy that the CA-SA/EP-based mortar exhibited a significantly uniform strain distribution, which were revealed by the use of Digital Image Correlation (DIC) technology. The research findings indicate that the CA-SA/EP-based mortar developed in this study has considerable potential for application in the field of building energy conservation.