In this study, we use urea-formaldehyde as the shell, phase change material (Hexadecane) as the core to prepare the microcapsules by interfacial polymerization method. In order to find out the best ratio of wall material, we fixed the weight of urea and changed the weight of formaldehyde. In this condition, change the temperature of polymerization and probe into the shape of the microcapsule. Add different weight of core and change the rotational speed to probe into the shape of the microcapsule and encapsulated ration, and use Frozen circulation machine to test the thermal nature of the microcapsules. The results show that the ratio of urea and formaldehyde for 1:2 is the best ratio of polymerization; temperature of polymerization at 45℃ is the most suitable; there is a suitable encapsulated ration with adding urea and formaldehyde with 1:2; microcapsules will have the best thermal property at 700rpm;The higher the rotational speed is; the time of sending out heat is the shorter.
