A novel thermal-insulating film incorporating microencapsulated phase-change materials for temperature regulation and nano-TiO2 for UV-blocking

Phase-change materials (PCMs) have promising applications in the fields of solar energy storage, energy conservation in buildings , thermal insulation , and thermal regulation. In this study, novel multifunctional composite films were prepared via a thermosetting process using poly(vinyl chloride) (PVC) as a film matrix, microencapsulated PCMs (micro-PCMs) as a temperature-regulating additive and TiO 2 nanoparticles (nano-TiO 2 ) as a UV-blocking additive. The latent heat of the film fabricated with 6   wt% micro-PCMs and 6   wt% nano-TiO 2 is 9.226   J/g. The film also shows high thermal stability, with no obvious change in thermal performance after 100 heating–cooling cycles. The temperature of a space enclosed by the film fabricated with 6   wt% micro-PCMs and 6   wt% nano-TiO 2 can be controlled in the range 25–28   °C for 3298   s. The composite films exhibit a significantly decreased UV transmittance due to the UV absorption of nano-TiO 2 . Furthermore, the thermal conductivity of the sample fabricated with 6   wt% micro-PCMs and 6   wt% nano-TiO 2 is 0.2356   W/(m   K), which is comparable with that of a pure PVC film. These findings indicate that the novel thermal-insulating film is promising for use in energy-efficient building and automobile applications.