| Abstract:In order to overcome the problem that hydrated salt phase change materials are prone to leakage during the energy storage phase change process, in this study, the porous structure of MFC/PVA/G aerogel carriers were prepared by freeze-drying technique using microfibrillated cellulose (MFC), polyvinyl alcohol (PVA), and graphene (G) as the raw materials, and a composite phase change energy storage material with excellent performance was prepared based on the loading of sodium sulfate decahydrate phase change material by vacuum impregnation method (MFC/PVA/G-PCM). The results show that MFC/PVA/G has good loading effect on sodium sulfate decahydrate, and has excellent dimensional stability and leakage prevention, and the thermal conductivity is improved by more than 150%. With the increase of PVA content, the specific surface area of MFC/PVA/G increased and the pore size decreased, and the enthalpy of MFC8/PVA2/G-PCM was the largest, with the solidification enthalpy of 169.46 J/g, the melting enthalpy of 217.8 J/g, and the solidification enthalpy of 165.56 J/g and the melting enthalpy of 171.53 J/g in the range of 0-50 ℃ after 300 phase change cycles. The solidification enthalpy was 165.56 J/g and the melting enthalpy was 171.53 J/g after 300 phase change cycles in the range of 0~50 ℃. In addition, the introduction of 4 wt% of borax into the sodium sulfate decahydrate phase change material can significantly improve the energy storage phase change performance of MFC/PVA/G-PCM, resulting in an increase in the crystallization temperature and a decrease in the supercooling degree (within 1 ℃). |