Hexamethylene dilauroyl, dimyristoyl, and dipalmytoyl amides as phase change materials for thermal energy storage

摘要

Hexamethylene dilauroyl, dimyristoyl, and dipalmytoyl amides have been produced as solid-liquid phase change materials via condensation of hexamethylene diamine with the respective acyl chlorides (lauroyl chloride, myristoyl chloride, and palmytoyl chloride) and were characterized by FT-IR, NMR, DSC, and TG analysis. Hexamethylene dilauroyl, dimyristoyl, and dipalmytoyl amides crystallized due to structural symmetry and flexibility of long alkyl groups. They were characterized by DSC and FT-IR spectroscopy before and after thermal cycling to determine their thermal reliability. Phase change enthalpies were found 110.1 and -103.3 J g~(-1) for hexamethylene dilauroyl amide (N,N' -hexamethylene didodecanamide), 116.9 and -110.4 J g~(-1) for hexamethylene dimyristoyl amide (N,N'-hexameth-ylene ditetradecanamide), and 144.5 and -140.5 J g~(-1) for hexamethylene dipalmytoyl amides (N,N'-hexamethylene dihexadecanamide) by DSC. The endurance of hexamethylene dilauroyl, dimyristoyl, and dipalmytoyl amides was studied by TG analysis.