Preparation of hydrophilic and fouling resistant poly(vinylidene fluoride) hollow fiber membranes

Amphiphilic brush-like copolymer P(MMA-r-PEGMA) was synthesized by a radical polymerization method. The copolymer was characterized by the nuclear magnetic resonance proton spectra (1H NMR) and gel permeation chromatography (GPC). Poly(vinylidene fluoride) (PVDF) hollow fiber membrane was then prepared by the phase inversion method using the copolymer as the macromolecular additive. The effect of P(MMA-r-PEGMA) on the phase inversion process was investigated using a light transmission experiment. The surface enrichment of amphiphilic copolymer in the PVDF hollow fiber was characterized by Fourier transform infrared attenuated total reflection spectroscopy (FTIR-ATR) and X-ray photoelectron spectroscopy (XPS). Morphological structures of both dry and wet membranes were observed by scanning electron microscopy (SEM). The hydrophilicity, water permeation flux, anti-fouling and carbon ink rejection performance of the hollow fiber were characterized respectively. All these results demonstrated that PVDF hollow fibers fabricated by the single-step method showed high permeation flux, good hydrophilicity and fouling resistance.