Preparation of PVDF hollow fiber membranes with high adsorption performance by one-step physical coating and chemical cross-linking

In this paper, PVDF hollow fiber membrane with high adsorption performance was prepared by coating polyvinyl alcohol on the surface of commercial PVDF hollow fiber ultrafiltration membrane and initiating partial hydroxyl acetalization. The modification effect was studied by scanning electron microscopy, infrared spectroscopy, contact angle test and organic dye adsorption capacity test. The results show that the polyvinyl alcohol is effectively fixed on the surface of PVDF hollow fiber membrane with polyvinyl alcohol used as coating agent to initiate partial acetalization reaction in the presence of glutaraldehyde and acid catalyst. The pure water contact angle of PVDF hollow fiber membrane decreases from 76.20° to 57.56°, which greatly improves the of PVDF hollow fiber membrane. The incorporation of the coating and cross-linked structure results in a decrease in the micro-porous permeability of the modified PVDF hollow fiber membrane. The adsorption performance of PVDF hollow fiber membrane modified by hydrophilic coating and cross-linked for organic dye Rhodamine B is significantly improved.