Hydrolysis modification of PVC/PAN/SiO2 composite hollow fiber membrane

A novel method was proposed to improve the hydrophilicity and permeation of poly (vinyl chloride)/polyacrylonitrile/SiO2 (PVC/PAN/SiO2) composite hollow fiber membranes (HFMs) by the interfacial hydrolysis of PAN between PVC and SiO2. PVC/PAN/SiO2 composite HFMs were prepared by phase inversion method, using water as inner and outer coagulation. Sodium hydroxide solution was fed to the composite HFMs to introduce hydrolysis reaction. The Fourier transform infrared spectroscopy (FTIR), bubble point pore diameter and scanning electron micrograph (SEM) were used to characterize the chemical, pore size and morphological changes of the membranes. The changes of permeation performance and mechanical properties were also investigated. Water contact angle (WCA) and protein filtration were employed to evaluate the hydrophilicity and the anti-fouling performance of the membranes. The alkaline hydrolysis occurred in the composite HFMs, both water permeation and the anti-fouling performance were improved while mechanical strength was still kept at a high level.

► Preparation and hydrolysis of PVC/PAN/SiO2 composite hollow fiber membrane were investigated.
► The effect of hydrolysis on morphology and performance of the composite membranes were also studied.
► The interfacial micro-voids morphology changes with PAN hydrolysis.
► By the alkaline hydrolysis occurred, both water permeation and the anti-fouling performance were improved, while mechanical strength was still kept at a high level.