Effect of wall thickness of hollow TiO2 spheres on properties of polyacrylate film: Thermal insulation, UV-shielding and mechanical property

Hollow TiO2 spheres were fabricated by calcining the polystyrene-titania composite microspheres prepared via a sol-gel process of titanium tetrabutoxide (TBT) using cationic polystyrene (PS) spheres as template. The wall thickness of hollow TiO2 spheres was finely tuned between 13 nm and 94 nm by varying the amount of titania precursor from 0.43 wt% to 1.25 wt% based on polystyrene latex during the coating process. The thermal insulation, UV-shielding, and mechanical properties of polyacrylate (PA) film were obviously enhanced by introducing hollow TiO2 spheres via physical blending method. Moreover, these properties exhibit a trend of first good and then become worse with the wall thickness of hollow TiO2 spheres increasing. When the wall thickness of hollow TiO2 spheres is 43 nm, the properties of polyacrylate/hollow TiO2 composite film are optimum.