Preparation of a PCM Microcapsule with a Graphene Oxide Platelet-Patched Shell and Its Thermal Camouflage Applications

The improved efficiency of latent heat energy utilization has been worldwide accepted as an effective way to alleviate the associated environmental problems resulting from increasing energy consumption in the present day. Herein, a novel phase change material (PCM) paraffin-wax-embedded polymer microcapsule with a graphene oxide (GO) platelet-patched shell structure (wax@PDVB@GO) was prepared in a synergistic stable system where GO and amphiphilic macromolecule 1,1-diphenylethylene capped hydrolyzed poly(glycidyl methacrylate) coexist. The successful encapsulation of PCM wax and the tangential adhesion of GO on the surface of the microcapsule were proved by a series of tests including scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and Raman spectroscopy. Besides, differential scanning calorimeter test results showed that the encapsulation ratio, encapsulation efficiency, and thermal storage capacity of the PCM microcapsule have been improved by incorporation of GO. Moreover, the photothermal nature of GO enabled the prepared capsules realize photothermal responsiveness, which greatly enriched the application of PCM microcapsules in biomedical therapeutics and other fields. At last, infrared thermal images demonstrated that the excellent thermal sensitivity of the GO platelet-patched PCM microcapsule shell provided an efficient way to regulate thermal radiance according to the surrounding background, which made wax@PDVB@GO microcapsule-embedded composites a promising material in active thermal camouflage and stealth applications.