In order to inhibit the supercooling crystallization of microcapsule phase change materials (MicroPCMs),an n-octadecane (n-Oct) suspension containing zinc oxide (ZnO) nanoparticles was prepared by hydrothermal synthesis method using zinc chloride (ZnCl2) as the precursor,stearic acid (SA) as the surface modifier,and phase change material (n-Oct) as the reaction medium at the temperature of 140℃.The suspension was used as a phase change material to prepare MicroPCMs (ZnO/n-oct@PMMA) with a crosslinked polymethyl methacrylate (PMMA) as the wall by a suspension free radical polymerization.The scanning electron microscopy (SEM) and transmission electron microscopy (TEM) tests showed that the microcapsules had a core-shell structure,and the surface had depressions,with the particle size of 1～5μm,and the ZnO particles in the microcapsules were about 10～100nm.The differential scanning calorimetry (DSC) and thermogravimetric analysis (TG) tests indicated that the presence of ZnO had little effect on the heat resistance of the microcapsules,but it increased the heterogeneous nucleation crystallization enthalpy of the microcapsules by 47.8%,which well inhibited the supercooling crystallization behavior of the MicroPCMs.
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基金资助
山西省高等学校科技创新项目(2019L0966);吕梁市引进高层次科技人才重点研发资助项目(2017-011-01)
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