癸醇-棕榈酸/膨胀石墨低温复合相变材料的制备与性能

为了寻求温度段在2~3℃的低温相变材料，采用低共熔法，以理论计算为基础制备了癸醇-棕榈酸（DA-PA）二元复合相变材料。为提高其热导率，利用膨胀石墨（EG）的多孔特性，制备了最佳质量比为15∶1的DA-PA/EG复合相变材料。通过DSC、步冷曲线、红外光谱测试、SEM、Hot Disk热常数分析、高低温循环实验对复合相变材料的结构和性能进行了研究。实验结果表明，当DA-PA质量比为97.8∶2.2时的低共熔温度为2.9℃，相变潜热为203.6 J·g^-1。真空吸附后DA-PA被均匀地包裹在EG的多孔网状结构中，DA-PA/EG的相变温度为2.7℃，相变潜热为193.9 J·g^-1，热导率为1.416 W·（m·K）^-1，相比DA-PA提高了4.3倍。经过100次高低温循环后，DA-PA/EG仍保持良好的稳定性，在冷链物流中有较大的应用价值。

Preparation and properties of decyl alcohol-palmitic acid/expanded graphite low temperature composite phase change material

To find a low temperature phase change material with a temperature range of 2—3℃, a sterol-palmitic acid (DA-PA) binary composite phase change material was prepared by eutectic method based on theoretical calculation. To improve the thermal conductivity, the DA-PA/EG composite phase change material with the optimal mass ratio of 15:1 was obtained by using the porous characteristics of expanded graphite (EG). The structure and properties of the composite phase change material were studied by DSC, step cooling curve, FI-TR, SEM and high-low temperature cycle test. The results show that when the mass ratio of DA-PA was 97.8:2.2, the phase change temperature was 2.9℃ and the latent heat was 203.6 J·g^-1. After vacuum adsorption, DA-PA was uniformly encapsulated in the porous network structure of EG. The phase change temperature of DA-PA/EG was 2.7℃, the latent heat was 193.9 J·g^-1, and the thermal conductivity was 1.416W·(m·K)^-1, which was 4.3 times higher than DA-PA. After 100 times of high-low temperature cycles, the thermal properties of DA-PA/EG did not change much and still maintained good stability. The results show that the DA-PA/EG composite phase change material has great application value in the cold chain logistics.