Alumina (Al2O3) is an inorganic shell material with desirable properties such as high thermal conductivity, chemical stability, resistance to corrosion and high thermal diffusivity. In this work, microcapsules with myristic acid (MA) core and alumina shell were generated by sol–gel technique. Aluminum isopropoxide (AIP) has been used as a shell forming reagent. The analytical and thermal characterizations of microencapsulated MA@Al2O3 are reported. Three weight ratios of MA/ (AIP), (1:1), (1:0.75) and (1:0.5) were made by varying the compositions of MA and AIP. SEM results revealed that the MA@Al2O3 microcapsules have a spherical shape with a grain size of 2–5 μm. The maximum weight loss of microcapsules is comparatively higher than pristine material. Thermal stability of the MA improved after encapsulation. The DSC results revealed an encapsulation ratio 88% and encapsulation efficiency of 92% for the (1:1) ratios with a latent heat of 150 J/g during solidification and 147 J/g during crystallization.

中文翻译：

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用于热能储存的微胶囊氧化铝-肉豆蔻酸相变材料的合成、表征和热分析

氧化铝 (Al2O3) 是一种无机壳材料，具有高导热性、化学稳定性、耐腐蚀性和高热扩散性等理想特性。在这项工作中，具有肉豆蔻酸（MA）核和氧化铝壳的微胶囊是通过溶胶-凝胶技术制备的。异丙醇铝 (AIP) 已被用作壳形成剂。报道了微囊化 MA@Al2O3 的分析和热表征。MA/(AIP)、(1:1)、(1:0.75)和(1:0.5)的三种重量比通过改变MA和AIP的组成制成。SEM 结果表明 MA@Al2O3 微胶囊呈球形，粒径为 2-5 μm。微胶囊的最大重量损失相对高于原始材料。封装后 MA 的热稳定性得到改善。