Preparation, characterization and latent heat thermal energy storage properties of micro-nanoencapsulated fatty acids by polystyrene shell

This work deals with the synthesis, physico-chemical characterization and latent heat thermal energy storage (LHTES) properties of micro-nanoencapsulated capric, lauric and myristic acids with polystyrene (PS) by using emulsion polymerization method. In synthesized micro-nanocapsules, the fatty acid has a function of phase change material (PCM) while PS acts as a shell material. The micro-nanoencapsulated PCMs (M-NEPCMs) were characterized chemically and morphologically by using Fourier transform infrared (FT-IR) spectroscopy, particle size distribution (PSD), and polarized optical microscopy (POM) and scanning electron microscopy (SEM) analyses methods. Differential scanning calorimeter (DSC) analysis showed that the fabricated M-NEPCMs melt and freeze in the temperature range of 22–48 °C and 19–49 °C as they storage and release a latent heat in range of 87–98 J/g and (−84) J/g–(−96) J/g. The M-NEPCMs were subjected to a thermal cycling test consisted with 5000 heating/cooling processes and the results revealed that their LHTES properties were changed slightly. The M-NEPCMs had good thermal durability and reasonable thermal conductivity values. These advantageous properties make them potential LHTES materials for thermal regulating, solar heat pumps and solar space heating–cooling applications in buildings.