Electrospun PLA/DTAC Bicomponent Membranes for Low-Resistance and Antibacterial Air Filtration

Polylactic acid (PLA) fiber membranes fabricated through electrospinning exhibit significant potential for air filtration. However, their efficiency in filtering highly permeable particulate matter (PM) is limited, as these particles can carry various bacteria and toxic substances. To address this challenge, the dielectric properties of PLA are enhanced by incorporating dodecyl trimethyl ammonium chloride (DTAC), leading to the formation of a bimodal micro/nanofiber structure via conjugated electrospinning. This innovative structure effectively reduces air resistance while maintaining high filtration efficiency. The filtration performance, including filtration efficiency, pressure drop, long-term stability, and overall effectiveness, was systematically investigated. The results demonstrate that the conjugated electrospun filtration membrane achieves a filtration efficiency of 99.51% for PM0.3 and 99.97% for PM2.5. Additionally, it exhibits a high-quality factor (0.0555 Pa⁻¹ for PM0.3 and 0.0846 Pa⁻¹ for PM2.5), long-term stability (with PM0.3 efficiency decreasing by only 2.78% and PM2.5 efficiency decreasing by 0.01% after two months), and excellent bactericidal effects against <i>E. coli</i> and <i>S. aureus</i> due to the incorporated DTAC. Therefore, this method not only enhances filtration efficiency and reduces filtration resistance but also provides an effective approach for developing efficient filtration materials with antibacterial properties.