(TiO2/Ag nanoparticles)@(chitosan-polyvinyl alcohol) core-shell nanofibers as novel anticorrosion and antibacterial improvers for epoxy coating systems

Core-shell nanofibers consisted of chitosan/polyvinyl alcohol as shell and TiO 2 /Ag nanoparticles as core (abbreviated as (TiO 2 @AgNPs)@(CS/PVA)) are synthesized by electrospinning method for improving the functional properties of the epoxy polymer coatings. The agglomeration of the core-shell network is prevented through fabrication on carbon steel surface. Meanwhile, the presence of unique amine and hydroxyl functional groups on the surface of the CS/PVA nanofibers would provide a crosslinking with the epoxy resin molecules with merits of reducing the gaps between epoxy coating and fillers and enhancing the blocking effect of the fibers. The electrochemical impedance spectroscopy reveals that the resistance of the epoxy coating loaded with the core-shell nanofibers is almost 3 times more than that of the blank sample during 30 days of soaking in the 3.5 wt% NaCl electrolyte. Moreover, the (TiO 2 @AgNPs)@(CS/PVA)/epoxy coating has shown high antibacterial activity against S. aureus with the highest antibacterial rate of 87% after 24 h storage in the solution of phosphate buffer salt. The developed core-shell nanofibers embedded within epoxy coating with enhanced anticorrosion and antibacterial properties could provide a promising application in various maritime fields for achieving both anticorrosion and antifouling properties in one coating system.