Synthesis and thermal energy storage properties of ethylene dilauroyl, dimyristoyl, and dipalmitoyl amides as novel solid–liquid phase change materials

Ethylene dilauroyl, dimyristoyl, and dipalmitoyl amides were synthesized as novel solid–liquid phase change materials (PCMs) via condensation of ethylene diamine with the respective carboxyl chlorides (lauroyl chloride, myristoyl chloride, and palmytoyl chloride). The synthesized ethylene dilauroyl amide (EDLA), ethylene dimyristoyl amide (EDMA), and ethylene dipalmytoyl amide (EDPA) were characterized structurally by FT-IR and 1H NMR spectroscopy techniques. Latent heats of melting and freezing determined using DSC technique were found to be 127.83 and −118.30 J/g for EDLA, 129.95 and −132.40 J/g for EDMA, and 150.66 and −145.22 J/g for EDPA, respectively. Phase change temperatures of these PCMs were ranged between 38.5 and 52.5 °C. The synthesized PCMs were tested for durability by accelerated thermal cyclings including 1000 melting/freezing cycles. Besides the thermal endurance of the PCMs were determined by TG analysis. Based on the results it was concluded that EDLA, EDMA, and EDPA compounds synthesized as novel solid–liquid PCMs have considerable amount of thermal energy storage potential in terms of suitable phase change temperatures, high latent heats, thermal reliability, and thermal stability. Moreover, the other advantages of the synthesized PCMs over the fatty acids used are better odor, low corrosivity, and low sublimation rates.

Graphical abstractEthylene dilauroyl, dimyristoyl, and dipalmitoyl amides (EDLA, EDMA, and EDPA, respectively) were synthesized as novel solid–liquid phase change materials (PCMs) via condensation of ethylene diamine with the respective carboxyl chlorides (lauroyl chloride, myristoyl chloride, and palmytoyl chloride). Latent heats of melting and freezing determined using DSC technique were found to be 127.83 and −118.30 J/g for EDLA, 129.95 and −132.40 J/g for EDMA, and 150.66 and −145.22 J/g for EDPA, respectively.Figure optionsDownload full-size imageDownload as PowerPoint slideResearch highlights► Novel solid–liquid phase change material with amide functionality. ► Synthesis and thermal characteristics of ethylene dialkyloylamides as novel phase change materials. ► Thermal energy storage properties of ethylene dialkyloylamides as novel phase change materials. ► Ethylene dialkyloylamides as novel phase change materials for thermal energy storage.