SELF-ASSEMBLED SYNTHESIS OF MICROENCAPSULATED PARAFFIN WAX PHASE CHANGE MATERIALS WITH EXCELLENT THERMAL PROPERTIES OF CALCIUM CARBONATE SHELL

The PW@CaCO₃ phase change microcapsule composites with paraffin wax (PW) as core and calcium carbonate (CaCO₃) as shell were successfully prepared by the self-assembly method. During the preparation process, different core-to-wall ratios and different temperatures affected the morphology, encapsulation rate, thermal stability, and thermal conductivity of the microcapsules. Eight sets of microcapsule samples were prepared under different core-to-wall ratios and different temperatures. Of these microcapsule samples, it was found that the microcapsules performed the best thermal performance at a temperature of 65° C and a core-to-wall ratio of 1:1, with a melting enthalpy of 102.8 ± 1.7 J/g, a crystallization enthalpy of 103.9 ± 1.8 J/g, an encapsulation rate of 73.7 ± 1.5%, and a thermal conductivity of 1.251 ± 0.026 W/(m K). The results showed that the prepared microcapsules have good thermal storage properties and have good prospects for application in the field of energy storage buildings.