Fabricating multifunctional PLA textiles with advanced respiratory detection and environmental safety

Currently, polylactic acid (PLA) is an attractive alternative to polypropylene (PP) because of its biodegradability. This study introduces a novel modification strategy for PLA by creating a multifunctional ionization layer with ionic salts. This approach achieves humidity sensing, reliable antibacterial properties, and excellent degradability simultaneously. The modified PLA textile sensor exhibits high sensitivity to respiratory humidity (0.92 at 90% RH), with ultrafast response (0.12 s) and recovery times (0.16 s). Additionally, the textile demonstrates excellent antibacterial performance against both E. coli (99.9%) and S. aureus (99.9%) after 1 h of contact. It also shows notable biodegradability with a weight loss rate of 60.38% after 30 days. Also, the ionic salt mechanism is explained through dynamic ionization interactions attributed to the modified ionic salts, which feature both long-chain alkanes and active ions. This work presents a new method to enhance the respiratory detection and antibacterial performance of biodegradable masks.