The solvent induced interfiber adhesion and its influence on the mechanical and filtration properties of polyethersulfone electrospun nanofibrous microfiltration membranes

Electrospun nanofibrous membranes (ENMs) as a novel class of energy saving membranes are under extensive investigation. This kind of membranes are highly porous and permeable however mechanically weak. In the current study, we benefited the residual solvent of the electrospun nanofibers to induce an interfiber adhesion through a thermal treatment. This approach was successful in enhancement of the mechanical properties of the electrospun nanofibrous membrane probed via tensile test and nanoindentation as a higher elastic modulus and compaction resistance, respectively. The mechanically stronger membrane possesses a higher resistance against tensile disintegration thereby a lower water flux at high feed pressures. Through a particle challenge test i.e. filtration of a TiO2 aqueous nanosuspension under an incremental feed pressure of 1-2 bar, we could also show that a mechanically resistant ENM can offer a more optimum filtration efficiency mainly due to its higher structural integration. (C) 2012 Elsevier B.V. All rights reserved.