The paraffin wax microcapsule PCM with VO2 shell for the thermal management

Paraffin wax is a common solid-liquid phase change material (PCM) with high latent heat in the field of thermal management, and VO2 is an interesting solid-solid phase change material with reversible phase transition at 68 °C. However, the leakage of paraffin wax is a fatal flaw that limits its practical applications. In thermal management applications, the paraffin core is wrapped with an organic or inorganic shell to stabilize the shape. Unfortunately, this can lead to a significant reduction in the overall latent heat. Here, we propose a new VO2-paraffin (C26H54) PCM structure for the first time. The VO2-paraffin PCM is synthesized by an emulsion polymerization. The VO2-paraffin PCM shows an excellent thermal stability, large overall latent heat (163 J/g) and a largely improved thermal conductivity (1.53 W/mK).