Bimodal structure in electrospun Zein/PLA-chitosan films with enhanced filtration efficiency and low pressure drop

This study utilizes electrospinning to develop bio-based fibrous films composed of zein and polylactic acid (PLA), with chitosan added in varying concentrations. The resulting films exhibit remarkable filtration efficiency, capturing over 95 % of airborne pollutants, while maintaining a low pressure drop of less than 4 mbar. A key innovation in this work is the integration of chitosan. Chitosan, a naturally derived polysaccharide, significantly increases the conductivity and viscosity of the spinning solution, enhancing interactions among PLA, chitosan, and protein molecules. This leads to a robust network structure with improved hydrophobicity and a bimodal structure, both essential for maintaining high filtration efficiency without reducing breathability. The addition of chitosan effectively addresses the common issue of high pressure drop in PLA/zein composite films, improving the product's efficiency and practicality for air filtration applications. Furthermore, the inherent mechanical strength and ductility of chitosan contribute to the fibrous films' overall durability and functionality. These properties make chitosan-modified zein/PLA fibers highly suitable for air pollution control, especially in personal protective equipment. This research underscores the potential of chitosan-enhanced bio-based materials as sustainable and effective solutions for advanced air filtration technologies.