Synthesis and Characterization of Zwitter ion Functionalized Polysulfone Membrane

Abstract The main target of the present research work is synthesis of structurally modified polysulfone (PSF) membrane with good anti‐fouling property. Fouling is a big problem in polymeric membrane field. This can be reduced by introducing the zwitter ionic structure on the polymeric backbone. In this research work, anti‐fouling of PSF membrane was taken as s challenge and successfully done via Friedel‐Crafts (FC) alkylation reaction. For the sake of comparison, the FC alkylation reaction of chloroethylamine (CEA) and chloroaceticacid (CAA) onto PSF backbone was done in a single step and two step reactions in the presence of AlCl 3 as a catalyst. The structurally modified PSF was characterized by FT‐IR spectrum, 1 H‐NMR spectrum, XPS, EDX, SEM, DSC, TGA, WCA and POM. The porosity and antimicrobial properties of simultaneously acid and amine functionalized PSF membrane was tested. The single step reaction exhibited a peak in the FT‐IR spectrum at 1669 cm −1 corresponding to the zwitter ionic structure. The same peak was absent in the two step reaction. The PSF4 system showed the lowest WCA of 32.4° and confirmed the increase in hydrophilicity of the membrane material. The thermal stability of the PSF before and after the structural modification reaction was internally analyzed and compared with the literature values.