Impact of nodular structure in characterization of three thin film composite membranes made from 1,2-benzisothiazol-3(2H)-one, sodium salt

This study identifies nodular structure as a major property that affects other properties of membranes and consequently may affect their performances in water treatment. Three commercially available membranes made 1,2-benzisothiazol-3(2H)-one, sodium salt were characterized using SEM-EDX, AFM, FTIR, XRD, TGA and sensile drop measurement. EDX and FTIR revealed the similarity of the polymer base of the three membranes, however, XRD identified that different additives might have been used during the fabrication process. SEM and AFM analysis confirmed the presence of nodular structure at different magnitude on each membrane and differentiated their properties. Fourier transform infrared analysis showed the functional groups at 1650 cm- 1 which indicated that polymerization took place during the fabrication of these membranes. The degree of polymerization might have been varied to result in different nodule sizes. In all the roughness parameters increase with increase in the nodule sizes, and the membrane with biggest nodule sizes demonstrated highest value of contact angle.