Electrospinning of chitosan (CS) is typically limited by poor spinnability and weak structural stability. In this study, polyvinylpyrrolidone (PVP) was incorporated into CS/polyvinyl alcohol (PVA) blends, followed by glutaraldehyde (GA) crosslinking, to optimize fiber morphology and mechanical performance. Morphological analysis indicated that PVP reduced the average fiber diameter to 80 nm by lowering surface tension and enhancing chain entanglement. XRD analysis revealed a significant reduction in crystallinity (or suppression of the crystalline phase), suggesting that PVP disrupted the ordered packing of chains. The incorporation of PVP significantly improved the elongation at break from 7% to 76%. Subsequent GA crosslinking further reinforced the dense network, resulting in a robust membrane with a maximum tensile strength of 32 MPa (a 60% increase) while maintaining a final elongation of 13.2%. The synergistic strategy of PVP-driven jet stabilization and GA-induced network reinforcement provides an effective route to fabricate high-performance nanofibers for potential biomedical and separation applications.
Ji et al. (Fri,) studied this question.