Abstract In this study, reversible photochromic polyurea (PU) microcapsules had been innovatively designed and prepared by in-situ polymerization successfully, which exhibited good latent heat storage and release properties. For the microcapsules, butyl stearate containing photochromic dye (spirooxazine) was used as the core material and PU as the shell material. The surface morphology, melt crystallization, thermal cycling durability, thermal stability and mechanical properties of PU microcapsules were systematically investigated with field emission scanning electron microscope (FE-SEM), different scanning calorimetry (DSC), thermogravimetric (TG) and dynamic mechanical analysis (DMA). And the light-to-thermal conversion performance was studied under sun simulation system. The results showed that the microcapsules synthesized with F2850, a new lipophilic amine, had better morphologies and uniform particle size distribution. When the mass ratio of isophorone diisocyanate (IPDI) to F2850 was 1:2, the surface of the microcapsules was smooth and compact thus resulting in the microcapsules with the highest mechanical strength. In addition, the PU microcapsules exhibited high energy storage efficiency, excellent thermal stability and thermal cycling durability. Finally, the reversible photochromic microcapsules also presented prominent light-to-thermal conversion properties. What’s more, the temperature of the reversible photochromic microcapsules was nearly 4.9 oC higher than that of microcapsules at the same irradiation time.

中文翻译：

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原位聚合可逆光致变色储能聚脲微胶囊

摘要 本研究创新性地设计并通过原位聚合成功制备了可逆光致变色聚脲（PU）微胶囊，该微胶囊具有良好的潜热储存和释放性能。对于微胶囊，使用含有光致变色染料（螺恶嗪）的硬脂酸丁酯作为核材料和聚氨酯作为壳材料。采用场发射扫描电子显微镜(FE-SEM)、差示扫描量热法(DSC)、热重分析法(TG)和动态力学分析系统研究了PU微胶囊的表面形貌、熔体结晶、热循环耐久性、热稳定性和力学性能。 DMA）。并在太阳模拟系统下研究了光热转换性能。结果表明，用F2850合成的微胶囊，一种新型亲脂胺，具有更好的形态和均匀的粒度分布。当异佛尔酮二异氰酸酯(IPDI)与F2850的质量比为1:2时，微胶囊表面光滑致密，微胶囊的机械强度最高。此外，PU微胶囊表现出高储能效率、优异的热稳定性和热循环耐久性。最后，可逆光致变色微胶囊还表现出突出的光热转换特性。更重要的是，可逆光致变色微胶囊的温度比相同照射时间的微胶囊高近4.9 oC。微胶囊的表面光滑致密，从而使微胶囊具有最高的机械强度。此外，PU微胶囊表现出高储能效率、优异的热稳定性和热循环耐久性。最后，可逆光致变色微胶囊还表现出突出的光热转换特性。更重要的是，可逆光致变色微胶囊的温度比相同照射时间的微胶囊高近4.9 oC。微胶囊表面光滑致密，因此微胶囊具有最高的机械强度。此外，PU微胶囊表现出高储能效率、优异的热稳定性和热循环耐久性。最后，可逆光致变色微胶囊还表现出突出的光热转换特性。更重要的是，可逆光致变色微胶囊的温度比相同照射时间的微胶囊高近4.9 oC。可逆光致变色微胶囊还具有突出的光热转换特性。更重要的是，可逆光致变色微胶囊的温度比相同照射时间的微胶囊高近4.9 oC。可逆光致变色微胶囊还具有突出的光热转换特性。更重要的是，可逆光致变色微胶囊的温度比相同照射时间的微胶囊高近4.9 oC。