Environmentally benign chitosan-based nanofibres for potential use in water treatment

Abstract Chitosan (CS)-based nanocomposite materials are highly prone to swelling when in contact with water. It is therefore essential to modify them to enhance their resistance to swelling, in order to be applicable in water treatment. In this study, the CS-based nanofibres were prepared using the electrospinning technique. The nanofibres were prepared from a polymer blend of CS, and other polymers (polyacrylamide (PAA) and polyethylene glycol (PEG)) added in small optimized quantities to enhance the ability to electrospun CS. Elastic polyisoprene (PIP) and functionalized multi-walled carbon nanotubes (f-MWCNTs) were incorporated in the electrospinnable solution blend of CS, PAA and PEG to reduce the swelling behaviour of the CS-based nanofibres and to improve their mechanical strength and thermal properties. PIP did not only improve the morphology of the resulting nanofibres but also reduced their swelling behaviour by twofold. The addition of f-MWCNTs was found to improve the tensile strength of the nanofibres by twofold, relative to nanofibres with no f-MWCNTs. The thermal degradation of the nanofibres was improved by a magnitude of 50°C. Antibacterial silver (Ag) and iron (Fe) nanoparticles (NPs) were embedded on the nanofibres for their possible use in disinfection processes. These NPs have demonstrated a potential to kill bacteria in water and, therefore, the prepared nanofibres can be used in disinfection water treatment processes with reduced swelling capacity.