Improved salt rejection, hydrophilicity and mechanical properties of novel thermoplastic polymer/chitosan nanofibre membranes

The present study reports on the preparation of novel nanofibre membranes from the thermoplastic polymer polyvinylidene fluoride coated with chitosan to enhance membrane properties such as hydrophilicity, mechanical properties, water flux and salt rejection. Initially, a supporting layer was produced from polyvinylidene fluoride using phase inversion methods, followed by being coated with chitosan using either electrospinning or immersion methods. Two types of fabricated membranes with different coating methods were characterized and tested for physical and chemical performance using field-emission scanning electron microscopy, tensile tests, permeation tests (water flux and salt rejection) and contact angle measurements. It was found that the support membrane (polyvinylidene fluoride) produced by the phase inversion method that was coated with chitosan using electrospinning showed better performance, with a salt rejection up to 70% for MgSO4, a decreased the contact angle (52°) and improved the elongation at the breaking point (~82%).