Adhesion‐Resistant, Sandwich‐Structured Zein Nanofiber Membrane for Air Filtration

To address the adhesion problem of curcumin‐containing zein fibers, sandwich‐structured zein/poly(vinyl alcohol) (PVA) membranes with a curcumin‐functionalized core layer were fabricated via sequential electrospinning (outer‐core‐outer). The core layer exhibited flattened and adhesive fibers, whereas encapsulation within protective outer layers yielded cylindrical, non‐adhesive fibers with tunable diameters (0.43–1.0 μm). The sandwich membranes exhibited enhanced mechanical properties (tensile strength up to 4.67 MPa) and stable hydrophobicity. Filtration tests demonstrated > 95% efficiency for 0.3 μm particles and > 97% for particles ≥ 0.5 μm, with pressure drop values ranging from 7.03 to 7.56 mbar. Post‐filtration imaging revealed that curcumin‐containing membranes displayed dispersed particle deposition on individual fibers, while the curcumin‐free outer layer showed extensive particle aggregation, indicating curcumin‐induced particle anchoring. FTIR analysis confirmed curcumin‐mediated hydrogen bonding and increased β‐sheet content. The sandwich design resolves core layer adhesion while preserving filtration functionality, offering a sustainable strategy for bio‐based air filtration materials.