Using co-electrospinning method to regulate phase change temperatures of fatty acid eutectic/polystyrene/fatty acid eutectic form-stable phase change composite nanofibrous membranes for thermal energy storage

Abstract

The seven kinds of fatty acid eutectics including capric-lauric acid (CL), capric-myristic acid (CM), capric-palmitic acid (CP), capric-stearic acid (CS), capric-lauric-myristic acid (CLM), capric-lauric-stearic acid (CLS) and capric-myristic-palmitic acid (CMP) were selected as solid-liquid PCMs. And then co-electrospinning method was used to produce and design innovative fatty acid binary eutectic/polystyrene/fatty acid binary eutectic (i.e., CL/PS/CL, CM/PS/CM, CP/PS/CP, CS/PS/CS, CL/PS/CM, CL/PS/CP, CL/PS/CS, CM/PS/CP, CM/PS/CS and CP/PS/CS) and fatty acid binary eutectic/polystyrene/fatty acid ternary eutectic (i.e., CL/PS/CLM, CM/PS/CLM, CP/PS/CLM, CS/PS/CLM, CL/PS/CLS, CM/PS/CLS, CP/PS/CLS, CS/PS/CLS, CL/PS/CMP, CM/PS/CMP, CP/PS/CMP and CS/PS/CMP) form-stable phase change composite fibrous membranes (PCCFMs) with the melting peak temperatures ranging from about 17 to 24 °C with the temperature interval of 1 °C. The scanning electron microscope images revealed that these electrospun PS-based form-stable PCCFMs exhibited well and stable nanofibrous network structure. The differential scanning calorimetry results indicated that the phase change temperatures of electrospun PS-based form-stable PCCFMs could be regulated to the lower temperature range by changing the type of the loaded fatty acid binary and ternary eutectics, and their phase change enthalpies were approximately 41–60 kJ/kg. Based on the consideration of phase change temperatures, the developed electrospun PS-based form-stable PCCFMs could be more suitable to use in temperature-regulated fibers and textiles as well as energy efficiency building applications.