Broad-spectrum corrosion-resistant nanofiltration membranes via reactive site-bridged nanofibrous network

Traditional nanofiltration membranes often struggle to maintain stability in harsh environments due to issues like swelling, chemical bond dissociation, and polymer chain creep. Fluoropolymers like poly(ethylene-chlorotrifluoroethylene) (ECTFE) are promising substrate candidates for broad-spectrum corrosion-resistant nanofiltration (CRNF) membranes, but their solvent insolubility and hydrophobicity present significant processing challenges. This study harnesses the electrospinnability and abundant reactive sites of polyvinyl alcohol to create a reactive site-bridged nanofibrous network. This network provides reactive sites to decorate the hydrophobic ECTFE substrate and bridges the molecular selective layer through aldolization, Schiff base reactions, and esterification. The resulting robust thin-film nanofibrous composite membranes exhibit high rejection rates for small molecular dyes under a variety of harsh conditions, including exposure to 10 wt% H₂SO₄, 1 M NaOH, ethanol, N,N-dimethylformamide, N-methylpyrrolidone, and 80°C solutions. This work paves the way for designing next-generation broad-spectrum CRNF membranes, enhancing their applicability in diverse harsh environments.