Flexible nanofibers-reinforced silk fibroinfilms plasticized by glycerol

Abstract: The difficulty of dispersingnanofillers and the insufficient of flexibility remains major obstacle to theexpansion of nanocomposite applications. In this study, silk fibroin (SF) basednanocomposite materials were obtained using glycerol plasticized SF as thematrix and short polymer nanofibers as the reinforcing phase. Highly flexibleSF films with silk I structure were fabricated by using glycerol as aplasticizer. More importantly, plasticizer glycerol significantly improved thehomogeneous dispersion of short PVA-co-PE nanofibers in SF films throughinterfacial interactions, forming flexible and robust nanofiber-reinforcedcomposite films. FTIR and XRD results showed that no significant change wasfound on secondary structure and crystal structure of SF protein after addingPVA-co-PE nanofibers. It was found that nanofiber content showed significantinfluence on the mechanical behavior of nanocomposite films, where the additionof 5–10% short PVA-co-PE nanofibers is preferred for achieving enhanced flexibilityand strength. This study provides new options for the fabrication of robust andflexible SF nanocomposites for functional applications.

Li Xiufang, et al. Flexiblenanofibers-reinforced silk fibroin films plasticized by glycerol. CompositesPart B: Engineering, 2018, 152, 305-310.