Effect of curing temperature on the performance of microencapsulated low melting point paraffin using urea-formaldehyde resin as a shell

Microencapsulated phase change materials (MicroPCMs) containing paraffin with low melting temperature were prepared by in situ polymerization using urea-formaldehyde resin as shell material. The curing stage was very crucial in determining the properties of the MicroPCMs. The effects of curing temperature on thermal properties, diameter distributions and surface morphology were systematically investigated by using differential scanning calorimetry, thermogravimetry analysis, a mean particle size distribution meter and scanning electronic microscopy. The obtained results indicate that the optimum curing temperature is 65℃. Under this condition, the paraffin mass content of MicroPCMs is 52.8%, and the enthalpy of MicroPCMs containing paraffin of 52.8% is 74.2 J/g. In addition, the mean volume particle diameter of MicroPCMs is 4.57 µm with particle size distribution of 0.37. The thermal resistant temperature of MicroPCMs is 220℃. Based on the results, it can be considered that MicroPCMs prepared at a curing temperature of 65℃ have good energy storage potential and temperature resistance. Therefore, they can be used to produce nonwoven materials by melt-blow.