Nano-enhanced sulfonated poly(arylene ether sulfone) composite membranes and their characterization

Abstract

Chlorine is a widely used oxidizing agent in desalination to control bacteria that cause biofouling. The lack of chlorine resistance in commercial desalination membranes urged the development of an alternate polymer material. In this study, commercially available copolymer (SES0005, AquafoneTM), resistant to dissolved chlorine in water, has theoretical IEC of 2.08 meq.g-1 is blended with 0.5-15 %(w/w) TiO2 nanoparticles of <25 nm diameter and 45-55 m2.g-1 surface area by using ball milling device. SEM-EDS (Scanning Electron Microscope-Energy Dispersive Spectroscopy) result supports TiO2 content and uniform distribution. The chlorine stability of membranes was evaluated in sodium hypochlorite solution from 100 to 2000 ppm (pH 9). TGA and FT-IR analysis were performed for these membranes. The 1.5 %(w/w) TiO2 nano-enhanced membrane water retention is 23 % which is ∼53 % higher than that of pristine (15 %) membrane. Tensile strength of pristine and 0.5 %(w/w) TiO2 nano-enhanced membrane is 23, and 44 MPa, respectively. TiO2 nanoparticle addition improved dimensional and mechanical properties. This study attempts to correlate the SES polymer-TiO2 interactions with the characterization techniques.