【摘要】 为了解决低温相变材料稳定性差、不易储存运输等问题,以六亚甲基二异氰酸酯(HDI)、1,3-丙二胺为壁材单体,以相变温度较低、相变潜热较高的十二醇为芯材,通过界面聚合法制备了低温相变微胶囊。由于十二醇具有反应活性,本工作研究了不同结构异氰酸酯作为壁材单体的适应性,探索了1,3-丙二胺水溶液的pH值对微胶囊形貌的影响。在1,3-丙二胺水溶液的pH值为9.0的情况下,制备的微胶囊粒径约2.0μm,芯材载量为79.8%,熔融温度为24.47℃,熔融热焓为142.3 J/g。相比于原位聚合法,界面聚合法制备的微胶囊有更好的致密性,在甲醇中的渗透率下降了40%,提高了十二醇相变材料的稳定性,有效改善了其泄漏、储存运输等方面的问题。更多还原

【Abstract】 To overcome the instability and difficulty in storage of low temperature phase change materials,microencapsulated phase change materials( MEPCMs) were synthesized via interfacial polymerization. Dodecanol,which exhibits low phase change temperature and great phase change latent heat was employed as the core material. However,dodecanol is capable of reacting with isocyanate groups. The reaction rate study of various isocyanates with dodecanol indicates that hexamethylene diisocyanate( HDI) can be used as the shell monomer for the preparation of microcapsules. Effect of the pH value of the 1,3-propanediamine aqueous solutions on the morphology of MEPCMs was explored. When the pH of the 1,3-propanediamine aqueous solution is about 9. 0,large amounts of microcapsules were obtained with an average diameter of about 2. 0μm,core content of 79. 8%,melting temperature of 24. 47 ℃ and melting enthalpy of 142. 3 J/g. In comparison to the in-situ polymerization,the MEPCMs prepared by the interfacial polymerization show better compactness,leading to a decreased permeability in methanol by 40%. Enhanced stability of MEPCMs effectively improves the issues of leakage,storage and transport for low temperature phase change materials.更多还原