肉豆蔻酸-十四醇二元复合相变材料的相变特性研究

Phase transition property of MA-TD binary composite phase change material

以肉豆蔻酸(MA)和十四醇(TD)为原料,采用熔融共混法制备了MA-TD二元复合相变材料,利用步冷曲线法测定不同质量比的MA-TD复合相变材料的结晶温度,绘制相图获得二元体系低共晶点,确定了MA-TD共晶混合物的质量比为36∶64,其结晶温度为32.7℃。差示扫描量热测试结果表明MA-TD共晶混合物的相变潜热为227.08kJ/kg。傅里叶变换红外光谱测试表明,复合相变材料中MA和TD的分子结构未发生变化,两者为物理复合。经过500次0~60℃冷热循环,MA-TD二元复合相变材料的相变温度基本不变,说明该复合相变材料的热稳定性较好。

A kind of binary composite phase change material(PCM)was prepared by the melt blending method with myristic acid(MA)and tetradecyl alcohol(TD)as raw materials.The cooling curve method was used to measure the freezing points of the different components of PCM,the eutectic point of MA-TD binary system was determined by phase diagram drawn according to the cooling curves.It was shown that MA-TD binary system achieved the eutectic point at about 32.7℃and the mass ratio of MA and TD was 36∶64.The DSC test results showed that the phase change latent heat of MA-TD eutectic mixture was about 227.08kJ/kg.The Fourier transform infrared spectrum(FT-IR)of binary eutectic mixture showed that the molecular structure of MA and TD in composite materials did not changed,and the mixing was physical recombination.After 500 times cold-heat cycle between 0 to 60℃,the phase change temperature of PCM was almost unchanged.It was shown that the PCM had good thermal stability.