Synthesis and Application of Light Management with Thermochromic Hydrogel Microparticles

The intelligent control of solar energy transmission through the window is expected to reduce the energy consumption for thermal comfort in the building. However, the ability of current smart windows to adjust solar gain based on phase change material tunable extinction is not optimal. A thin film thermochromic device based on tunable light scattering of hydrogel particles of a specified diameter is reported. In the study, microparticles of poly (N-isopropylacrylamide) -2-aminoethyl methacrylate hydrochloride (pNIPAm-AEMA) having a low phase transition temperature of about 32 ℃ were synthesized. It is noteworthy that the average size of the pNIPAm-AEMA particles can be varied from 1388nm at 25 ℃ to 546nm at 35 ℃, resulting in an unprecedented modulation of infrared transmission of 75.6%, which is consistent with numerical simulations based on mie scattering theory. A high light transmission of 87.2% is achieved. The pNIPAm-AEMA device demonstrates tunable scattering with excellent stability and scalability, which can be applied in a wider light management area beyond energy-saving smart windows.