以SiO2为载体、癸酸-棕榈酸为相变材料,采用溶胶-凝胶法制备癸酸-棕榈酸/SiO2复合相变材料,考察了其储热性能、导热性能、微观形貌和组成结构. 结果表明,当癸酸-棕榈酸掺入量为0.08 mol时,所制材料具有最好的潜热性能,相变温度为20.02~22.08℃,相变焓为44.53~50.51 J/g,适合在建筑领域应用;当癸酸-棕榈酸掺入量为0.06 mol时,材料导热性能最好,导热系数在第一降温阶段为0.211 W/(m×K),相变平台阶段为0.017 W/(m×K),第二降温阶段为0.040 W/(m×K);材料中SiO2与癸酸-棕榈酸仅是物理嵌合,未发生明显的化学作用,癸酸-棕榈酸掺杂过量时明显包裹SiO2,导致复合相变材料潜热性能和导热性能下降.
Using SiO2 as carrier and decanoic acid-palmitic acid as phase change material, decanoic acid-palmitic acid/SiO2 composite phase change material was prepared by sol-gel method, its thermal storage and thermal conductivity performances, microstructure and composition structure were characterized. The results show that when the amount of decanoic acid-palmitic acid is 0.08 mol, the preapred material haa the best thermal storage performance, such as phase change temperature is 20.02~22.08℃ and phase transition enthalpy 44.53~50.51 J/g, being suitable for application in the field of architecture. When the amount of decanoic acid-palmitic acid is 0.06 mol, the material has the best thermal conductivity performance, such as its thermal conductivity in the first stage of cooling is 0.211 W/(m×K), 0.017 W/(m×K) in the stage of phase plateau and 0.040 W/(m×K) in the second stage of cooling. SiO2 in the material is physically embedded with decanoic acid-palmitic acid, there is no chemical reaction between them. When the content of decanoic acid-palmitic acid is excessive, by which SiO2 is covered, the thermal storage and thermal conductivity performances are decreased.