Polymer photonic aegises as near-infrared reflectors

\nYear by year, thermal shielding has seen an increase in importance for reduction of energetic consumption in vehicles and buildings as a passive method of cooling opposed to traditional antiecologic air conditioning. In this work, we report on the design and fabrication of flexible, multilayer polymer photonic crystals films, namely aegises. Exploiting their peculiar optical properties, aegises are designed to act as selective reflectors for the near-infrared radiation, principal cause of radiative heating by sunlight, while keeping a relative transparency in the visible range. Different polymers are used as alternating building blocks, and the efficiency of the fabricated structures is assessed via thermal experiments, achieving efficiencies greater than 25% in heating reduction.\n