Synthesis and characterization of microencapsulated myristic acid–palmitic acid eutectic mixture as phase change material for thermal energy storage

Abstract

In this work microencapsulation of myristic acid–palmitic acid (MA–PA) eutectic mixture with silica shell using sol−gel method has been attempted. The core phase change material (PCM) for thermal energy storage was myristic acid−palmitic acid eutectic mixture and the shell material to prevent the PCM core from leakage was silica prepared from methyl triethoxysilane (MTES). Thermal properties of the microcapsules were measured by differential scanning calorimeter (DSC). The morphology and particle size of the microcapsules were examined by scanning electronic microscope (SEM). Fourier transformation infrared spectrophotometer (FT–IR) and X–ray diffractometer (XRD) were used to investigate the chemical structure and crystalloid phase of the microcapsules respectively. The DSC results indicated that microencapsulated phase change material (MPCM) melts at 46.08°C with a latent heat of 169.69kJkg−1 and solidifies at 44.35°C with a latent heat of 159.59kJkg−1. The thermal stability of the microcapsules was analyzed by a thermogravimeter (TGA). The results indicated that the MPCM has good thermal stability and is suitable for thermal energy storage application.