二元脂肪酸/硅藻土助滤剂定形相变复合材料的制备及性能

Preparation and properties of binary fatty acid mixture/diatomite filter aid form-stable phase change composite

采用真空浸渗法制备了癸酸-月桂酸(CA-LA)/硅藻土助滤剂定形相变储热复合材料,对样品进行扩散-渗出圈测试、FTIR、SEM、BET、DSC和TG等表征分析,研究了硅藻土助滤剂对CA-LA二元低共熔脂肪酸的定形性能和吸附容量及CA-LA/硅藻土助滤剂定形相变复合材料的热物性、热稳定性和蓄放热性能。结果表明:无渗出圈产生的CA-LA/硅藻土助滤剂定形相变复合材料中,硅藻土助滤剂对CA-LA的吸附量约为49.88wt%,CALA/硅藻土助滤剂定形相变复合材料的相变温度和相变潜热分别为21.8℃和75.45J/g;TG和热循环试验结果表明,CA-LA/硅藻土助滤剂定形相变复合材料具有良好的热稳定性,经历100次热循环后相变温度和相变潜热的变化量较小;蓄放热性能测试结果证明CA-LA/硅藻土助滤剂定形相变复合材料能够进行蓄热和释热,起到明显的调节和控制环境温度的作用,可应用在建筑节能和储热领域。

The capric-lauric fatty acid（CA-LA）/diatomite filter aid form-stable phase change composite was prepared by vacuum impregnation method.The prepared form-stable PCM was characterized by diffusion-effusion circle test,FTIR,SEM,BET,DSC and TG technique in the form-stability,absorption mass,thermo-physical properties,thermal stability and heat storage/release performance.The results show that the adsorption capacity of the diatomite filter aid to the CA-LA eutectic is about 49.88 wt% without the effusion circle in the composite,and the phase change temperature and latent heat is 21.8℃ and 75.45 J/g,respectively.The CA-LA/diatomite form-stable composite has good thermal stability and reliability which proved by TG and melt/freezing cycling test.After 100 times thermal cycling,the phase change temperature and latent heat of the CA-LA/diatomite form-stable composite change a little.It is also revealed that the CA-LA/diatomite form-stable composite can charge and discharge latent heat so that the environment temperature can be adjusted and regulated in some degree.The prepared CA-LA/diatomite filter aid form-stable composite is promising to be applied in the building energy conservation and heat storage applications.