Stretchable and biodegradable composite films for disposable, antibacterial, radiative cooling system

[Display omitted] •Stretchable, biodegradable, antibacterial composites for personal protection tools.•Size-optimized particles within polymers for effective daytime radiative cooling.•Exposure of magnesium oxide particles for strong bactericidal activity. Materials that inhibit bacteria and viruses, while ensuring thermal comfort and physical ease, can play a significant role in the realm of protective textiles and equipment for outdoor healthcare activities, particularly in the context of recent global pandemics. Here, we develop radiative cooling and antibacterial composites consisting of stretchable, biodegradable poly(lactide-co-ε-caprolactone) (PLCL) and magnesium oxide (MgO) particles via a scalable solution casting process. Precise control over the size and composition of the particles within the polymer matrix through theoretical and experimental analyses achieves sub-ambient daytime radiative cooling (△T, ∼7℃) under diverse weather conditions. Bactericidal MgO particles through surface treatments realize a remarkable reduction of bacterial cell viability by ∼100 % in 8 h. The overall results suggest that materials with thermal and infection control capability as well as disposable characteristics have the potential to reduce plastic waste beyond the spread of infection.