新型建筑用二元复合定型相变材料的制备及性能评价

Preparation and performance evaluation of a new type of binary shaped phase change material for buildings

针对建筑节能领域,提出了一种由十二醇(LA,C12H26O)和硬脂酸(SA,C18H36O2)组成的具有适宜相变温区且相变潜热较高的二元相变材料LA-SA,并以膨胀珍珠岩和陶粒为多孔吸附材料制备出复合定型相变材料,探究了不同吸附材料对于定型相变材料热物性的影响。二元相变材料LA-SA的最优配比为质量分数82%十二醇+18%硬脂酸,其熔融相变温度为21.3℃,相变潜热为205.9 kJ/kg,且热稳定性能良好。以膨胀珍珠岩和陶粒为吸附材料,通过真空吸附法制备出了两种建筑用定型相变材料,并对其进行了SEM、FTIR、TG及DSC性能表征,结果表明:LA-SA与两种吸附材料的复合过程仅为物理吸附且复合良好,吸附后的定型相变材料的相变潜热有一定的降低;相比于陶粒,膨胀珍珠岩对相变材料的吸附率较高,且对相变材料热性能影响较小;LA-SA/膨胀珍珠岩熔融相变温度为22.7℃,相变潜热为165.3 kJ/kg,可应用于建筑节能材料的制备。

To reduce the energy consumption in buildings,a new binary phase change material(PCM),with suitable phase change temperature and relatively large latent heat,composed of lauryl alcohol(LA,C12H26O)and stearic acid(SA,C18H36O2)was proposed,namely LA-SA.The expanded perlite and ceramsite were used as adsorbent materials to prepare the shaped PCMs,and the thermophysical properties of the two shaped PCMs were investigated and analyzed.The optimal ratio of LA-SA was mass fraction of 82%LA+18%SA with melting temperature of 21.3℃,latent heat of 205.9kJ/kg and a good thermal stability.Two kinds of composite shaped PCMs for building were prepared by vacuum adsorption method using expanded perlite and ceramsite as the adsorbent materials.The properties of the two shaped PCMs were characterized by SEM,FTIR,TG and DSC.Results showed that only physical adsorption occurred during the good combination of LA-SA and the porous materials,and the latent heat of the shaped PCMs decreased after the adsorption.The adsorption rate of LA-SA/expanded perlite was higher than that of the LA-SA/ceramsite,and the expanded perlite had less influence on the thermal properties of the shaped PCM.The melting temperature of LA-SA/expanded perlite was 22.7℃and the latent heat was 165.3 kJ/kg,which could be used to prepare energy conservation-building materials.