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.