Preparation of PVDF/PVC composite membrane for wastewater purification

Abstract Polyvinylidene fluoride (PVDF) membranes are widely used in waste water purification and desalination for the advantages of excellent separation performance and good mechanical stability. However, high cost and inert to modification limit their application in many fields. Here, we prepare a novel membrane containing PVDF and polyvinyl chloride (PVC) using phase inversion method. The influence of polymers ratios on the structure and performance of the membranes is investigated. The porosity of the membranes is tested using weight differential method. And the result shows that the porosity increases with adding more PVC in the composite membranes. The flux does not proportionally increase with increasing the amount of PVC in the composite membranes. With adding a small amount of PVC (1 and 5%), the flux is dramatically larger than that of pure PVDF membrane; then it goes down with adding more PVC (10–20%). In order to find out the mechanism of increment in flux with adding small amount of PVC, the ...