Development, characterization, and latent heat thermal energy storage properties of neopentyl glycol-fatty acid esters as new solid-liquid PCMs

Neopentyl glycol (NPG) is known as a solid-solid phase change material (PCM) and shows a solid-solid phase transition at 41.9 C. Although it has a good latent heat capacity of 141.91 J/g, the low degradation temperature interval (80-150 C) is close to its solid-liquid phase change temperature (129.46 C), which lessens its latent heat thermal energy storage (LHTES) potential. The present study is aimed to eradicate these disadvantages by synthesizing its ester compounds with three kinds of fatty acid chlorides. The developed NPG-DL, NPG-DM, and NPG-DP esters were characterized using FT-IR and ¹H NMR spectroscopy techniques. The DSC results showed that the esters had a melting point and latent heat value in the range of about 11-35 C and 98-124 J/g. The synthesized PCMs had high decomposition temperature ranges, noncorrosivity, and good odor properties. The PCMs also exhibit good thermal reliability and chemical stability besides their increased thermal conductivity.