Comprehensive study on the light shielding potential of thermotropic layers for the development of new materials.

In recent years thermotropic overheating protection glazings have been the focus for both solar thermal collector technology and architecture. A thermotropic glazing changes its light transmittance from highly transparent to light diffusing upon reaching a certain threshold temperature autonomously and reversibly. In thermotropic systems with fixed domains (TSFD) the scattering domains are embedded in a polymer matrix, which exhibits a sudden change of the refractive index upon reaching a threshold temperature. The aim of the present study was to comprehensively investigate the light shielding characteristics and potential of TSFD materials by applying simulation of light scattering in particle-filled layers. In random walk simulations a variety of parameters were varied systematically, and the effect on the light transmission behavior of TSFD was studied. The calculation steps of the simulation process are shown in detail. The simulations demonstrate that there is great potential for the production of functional materials with high overheating protection efficiency.