微胶囊相变储能材料的制备和表征

Synthesis and characterization of microcapsule phase change material

以硬脂酸丁酯为囊芯,甲醛-三聚氰胺树脂为囊壁,采用原位聚合法合成了具有相变储热功能的微胶囊材料.采用光学显微镜观察微胶囊的形成过程,扫描电子显微镜和红外光谱表征微胶囊的表面形貌特征与化学结构.微胶囊表面粗糙,能够与建筑材料形成良好界面,在水泥和涂料等建筑材料中分布均匀,不破碎.采用DSC分析微胶囊储能材料的储热效果,硬脂酸丁酯/MF微胶囊储能效果明显,可以用于设计储能建筑材料.采用水化热测试仪研究该微胶囊对水泥水化热的影响,结果表明,储能微胶囊能降低水泥水化放热峰,提升放热低谷,提前第二放热峰的出现.储能微胶囊对水泥总体放热量影响较小,对水化热放热速率有明显影响,可用于混凝土水化过程中材料内部温度的控制.

Microcapsules phase change material （PCM） was synthesized by in-situ polymerization using melamine-formaldehyde resin as shell material and buty stearate as core material, which can store or release thermal energy while a phase change of the core material occurs. The formation of the microcapsules was observed by using optical microscopy, and the surface morphology of mierocapsules and shell chemical structure were characterized by using scanning electron microscopy and Fourier-transform infrared spectroscopy respectively. The microcapsule surface is so rough that the microcapsules can interface well with building materials such as cements and coating materials. The microcapsules distribute uniformly in the building materials and remain unbroken. The PCM was analyzed by using differential scanning calorimetry, the analysis indicating that the buty stearate and MF microcapsules have effective thermal energy capacity and can be used to design energy storage building materials. Cement hydration heat measurememts show that the microcapsules reduce the exothermic peak, elevate the valley and accelerate the arrival of the second peak for cement hydration, while mierocapsules have little influence on the total heat liberation and some influence on the heat liberation rate. Microcapsules PCM may be used to control the hydration temperature within the concrete structure.