Thermal properties of 3‐hydroxy fatty acids and their binary mixtures as phase change energy storage materials.

Summary: In the present work, we describe the chemical synthesis of 3‐HFAs as prominent derivatives of fatty acids and assess if they could be applied as phase change materials (PCM). In addition, 3‐HFAs were obtained by depolymerization of a bacterial biopolymeric material, polyhydroxyalkanoate. Thermal properties of 3‐hydoxyoctanoic, decanoic, and dodecanoic acids are reported for the first time. These materials showed the potential to be applied as PCM in temperature range from 33°C to 66°C. In order to expand the temperature range for application of 3‐HFAs as PCM, eutectic mass ratios of three kinds of binary mixtures of 3‐HFAs were calculated, and their properties were predicted using the Schröder‐van Laar equation. Thermal properties of these mixtures were validated by differential scanning calorimetry (DSC) analysis. These results showed that eutectics considerably expanded the scope of applications of 3‐HFAs as PCMs. 3‐HFAs originating from biotechnologically obtained polyhydroxyalkanoates also showed potential to be applied in development of PCMs. [ABSTRACT FROM AUTHOR]