Electrospun PEO/PEG fibers as potential flexible phase change materials for thermal energy regulation.

Polyethylene glycol (PEG) is widely used as phase change materials (PCM) due to their versatile working temperature and high latent heat. However, the low molecular weight of PEG prevents from the formation of flexible microfibers, and the common leakage problem associated with solid-liquid PCM further hinders their applications in various fields. To address these challenges, polyethylene oxide (PEO) is incorporated as the supporting matrix for PEG, leading to a successful electrospinning of fibrous mats. Due to the similar chemical nature of both PEG and PEO, the blended composites show great compatibility and produce uniform electrospun fibers. The thermal properties of these fibers are characterized by DSC and TGA, and supercooling for the PEG(1050) component is effectively reduced by 75-85%. The morphology changes before and after leakage test are analyzed by SEM. Tensile and DMA tests show that the presence of PEG(1050) component contributes to plasticization effect, improving mechanical and thermomechanical strength. The ratio of PEO(600K):PEG(1050) at 7:3 affords the optimal performance with good chemical and form-stability, least shrinkage, and uniformity. These fibrous mats have potential applications in areas of food packaging, flexible wearable devices, or textiles to aid in thermal regulation.