放射冷却および抗菌性鮮度保持のための階層的多孔質構造を有する熱可塑性ポリウレタンベース複合フィルム

Passive radiative cooling (PRC) technology achieves cooling by reflecting solar radiation and radiating heat to cold outer space through a transparent atmospheric window (8-13 μm). In this research, we developed a porous thermoplastic polyurethane doped with MgO (PTM) film with a hierarchical porous structure via a water-solvent phase separation method, which simultaneously realizes high-performance radiative cooling (solar reflectivity of 94%, mid-infrared emissivity of 0.95) and broad-spectrum antibacterial function. It achieved an average cavity cooling effect of 14.6 °C compared to a blank group at a solar radiation intensity of 630 W·m^-2, with a theoretical cooling power of 108.4 W·m^-2. Moreover, the PTM film has excellent antibacterial properties, with an inhibition rate of over 95% against Escherichia coli. The integrated dual functionality exhibits remarkable practical advantages: When applied to fresh strawberry preservation, this synergistic mechanism achieves 4-8 °C localized cooling compared with ambient conditions, effectively suppressing both enzymatic browning and bacterial growth. The treated strawberries maintained optimal freshness for at least 5 days, a significant extension compared to conventional storage. This performance is accomplished without external energy input, demonstrating the film's potential for zero-energy cooling and hygiene maintenance in food preservation systems.