Reflective and heat insulation coatings enabled by <scp>TiO₂</scp>@polyacrylate hybrid latex and bionic potassium titanate whisker for passive cooling

Abstract Reflective and heat insulation coatings are new types of materials coated on constructions. However, their applications are limited by the undesired insulation effect resulting from the poor reflectance in the solar spectrum of the coating film. In this study, a reflective and heat insulation coating is successfully developed by combining titanium dioxide@polyacrylate (TiO 2 @PA) hybrid latex with a core‐shell structure and an insulation filler of bionic potassium titanate whisker (PTW). The TiO 2 nanoparticles are distributed homogeneously in the polymer matrix due to the polymer‐encapsulated TiO 2 structure, achieving a total solar reflectance (TSR) of 71.0%. Notably, the as‐prepared reflective and heat insulation coating films exhibit excellent TSR of 86.0% enabled by TiO 2 @PA latex and PTW, attributed to the synergistic combination of TiO 2 @PA and PTW with high TSR. The temperature inside the room coated with the reflective and insulation coatings on the roof is 16.6°C lower than that of the uncoated one, while 20 wt% PTW is introduced into the coating formulation. The resulting reflective and heat insulation coatings are attractive for the fields of passive cooling such as building energy conservation, automotive body, and so on, endowing people with a comfortable life, especially in the hot summer.