Superhydrophobic polytetrafluoroethylene nanofiber membranes prepared by vacuum sintering and their application in vacuum membrane distillation

Abstract

Abstract Electrospinning‐sintering is a general strategy to fabricate polytetrafluoroethylene (PTFE) nanofibrous membranes. In this study, vacuum atmosphere was created in the sintering process to obtain pure PTFE fibers. The effect of vacuum pressure on fiber morphology and material component of the sintered membrane was investigated by scanning electron microscopy (SEM) and X‐ray photoelectron spectroscopy (XPS) characterization. A proper vacuum condition was believed to be beneficial to decrease poly(vinyl alcohol) residual and creating nanosize structures on the fiber surface, as porous, which contributes to a secondary roughness, while insignificantly influence membrane strength. As a result, the prepared membrane was superhydrophobicity with enhanced liquid entry pressure value. The anti‐wetting property of the vacuum sintered membranes was further evaluated by vacuum membrane distillation process, and ensured the superior wetting resistance of the vacuum sintered PTFE membranes.