Development and characterization of glycerol coating on the PAN/PVDF composite membranes

Abstract

Studies on investigating the effects of glycerol coating on the intrinsic and permeation properties of polyacrylonitrile (PAN) - polyvinylidene fluoride (PVDF) membranes were carried out. The surface properties of the membranes were determined by using field-emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), fourier transform infrared spectroscopy (FTIR) and contact angle goniometer. The percentage of shrinkage, pore size, porosity and the water permeation of the membranes were also studied. The presence of new - OH and C-O bands in FTIR spectra showed that glycerol was successfully coated on the surface of the membranes. It was found that with increasing glycerol concentration from 0 to 30 vol%, the membranes exhibited higher water flux due to lower contact angle and larger pore size. However, the water flux was decreased when more than 20 vol% of glycerol was used as the coating material. It was due to the pores blocking on membrane surface and decreased surface roughness as shown by the FESEM and AFM images. Overall, glycerol coating can be a promising coating material to improve the surface properties of the membrane and its permeability performance.