The effect of nucleating agent on the multiphase change materials for energy storage in buildings

Phase change materials (PCMs) have the potential to be used for widespread energy storage applications in buildings. However, available PCMs can only function at fixed phase transitional temperatures, restricting their seasonal applicability. To this end, some studies have been carried out to develop multiphase change materials (MCMs). Prior to having competitive advantage, their encapsulation efficiency needs to be improved. In this study, MCM has been developed by combining two microencapsulated PCMs (MEPCMs), through Van der Wall's interaction forces phenomenon. In-situ polymerisation was adopted to fabricate the MEPCMs by employing RT22 and RT64 as PCMs. The optimal amount of nucleating agent played a crucial role in obtaining high encapsulation efficiencies of microencapsulated RT22 (MERT22) and RT64 (MERT64) by 90.43% and 84.07%, respectively. The developed MCM achieved melting temperatures at 23.01 °C and 56.64 °C, with combined energy storage capacity of 163.17 J/g, and encapsulation efficiency of 83.81%. The MCM also had thermal stability temperature of 142.71 °C, exceeding common building operating temperature. The nucleating agent also affected the sample morphology and particle size distribution, which therefore requires optimisation. There is also the need for thermal enhancement since it remains as one of the limiting factors of PCMs.