Polyethylene Glycol Confined in SiO-Modified Expanded Graphite as Novel Form-Stable Phase Change Materials for Thermal Energy Storage.

Form-stable phase change materials (FSPCMs) composed of poly(ethylene glycol) (PEG) encapsulated in SiO-modified expanded graphite (EG@SiO) were prepared and investigated for thermal energy storage behaviors. The modification of SiO on EG was done using a simple sol-gel method, and then the resulting EG@SiO was introduced to confine PEG at varying content (60-90 wt %). Surface properties (including microstructure, morphology, and functional groups), PEG adsorptivity, leakage-proof ability, and thermal energy storage of the prepared materials were thoroughly characterized and discussed.