Preparation of Colored Microcapsule Phase Change Materials with Colored SiO2 Shell for Thermal Energy Storage and Their Application in Latex Paint Coating

This article reports the design and manufacture of colored microcapsules with specific functions and their application in architectural interior wall coating. Utilizing reactive dyes grafted SiO2 shell to encapsulate paraffin through interfacial polymerization and chemical grafting methods, this experiment successfully synthesized paraffin@SiO2 colored microcapsules. The observations of surface morphology demonstrated that the colored microcapsules had a regular spherical morphology and a well-defined core-shell structure. The analysis of XRD and FT-IR confirmed the presence of amorphous SiO2 shell and the grafting reactive dyes, and the paraffin possessed high crystallinity. Compared with pristine paraffin, the thermal conductivity of paraffin@SiO2 colored microcapsules was significantly enhanced. The results of DSC revealed that the paraffin@SiO2 colored microcapsules performed high encapsulation efficiency and desirable latent heat storage capability. Besides, the examinations of UV-vis and TGA showed that the paraffin@SiO2 colored microcapsules exhibited good thermal reliability, thermal stability, and UV protection property. The analysis of infrared imaging indicated that the prepared latex paint exhibited remarkable temperature-regulated property. Compared with normal interior wall coatings, the temperature was reduced by about 2.5 °C. With such incomparable features, the paraffin@SiO2 colored microcapsules not only appeared well in their solar thermal energy storage and temperature-regulated property, but also make the colored latex paint coating have superb colored fixing capabilities.