Surface modification of light hollow polymer microspheres and its application in external wall thermal insulation coatings

Purpose – The purpose of this paper is to modify light hollow polymer microsphere (LHPM) with titanium dioxide nanoparticles (nano-TiO2) to improve its compatibility with latex and apply the obtained nano-TiO2/LHPM composite particles in external wall thermal insulation coatings. Design/methodology/approach – The nano-TiO2/LHPM composite particles were prepared via vigorous stirring. The morphology and chemical composition of the produced nano-TiO2/LHPM composite particles were characterized using scanning electron microscopy, energy dispersion spectrum, thermo-gravimetric analyzer and Fourier transform infrared. The performance of this new composite coating was evaluated by checking its stability, density, radiation reflectivity, thermal conductivity and the resulting insulation temperature difference when forming coating film. Findings – It was found that a 9:1 mass ratio of nano-TiO2/LHPM with total 10 weight per cent composite particles in the thermal insulation paint showed low density, good stability, low thermal conductivity (0.1687 W/m·K) and high insulation temperature difference (5.8°C). Research limitations/implications – The LHPM can be modified by other nanoparticles to improve its insulation performance in thermal insulation coatings. Practical implications – This work provides a simple, robust, but effective approach to produce new thermal insulation coatings with nano-TiO2/LHPM composite particles. Originality/value – This method for surface modification of LHPMs is novel and the modified hollow polymer microspheres could be applied to external wall insulation coatings.