Properties and characterization of novel expanded dickite based composite phase change material

Expanded dickite as the carrier of loading polyethylene glycol (PEG), a novel composite phase change material (PCM) is synthetized. X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, specific surface area test, thermogravimetric analysis, and differential scanning calorimetry are used to characterize and evaluate the expanded dickite carrier and the composite PCMs. The results show that the heat released by the reaction of potassium chlorate and urea promotes the layer expansion of dickite to form a net-like porous structure. Two kinds of expanded dickite (EDU1 and EDU2) carriers are prepared by modulating the amount of potassium chlorate. EDU2 carrier with full layer expansion possesses a PEG load rate of 179.3%. The higher PEG load rate of EDU2 is attributed to its developed pore structure, and the hydrogen bond formed between PEG and expanded dickite. Composite PCM using EDU2 as the carrier has a higher latent heat of 98.22 J g(-1) and good thermal cycling stability.