Preparation and Properties of Dodecanol Microcapsules by Interfacial Polymerization

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 2.0 μm, 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. © 2021, Materials Review Magazine. All right reserved.