Design of Robust FEP Porous Ultrafiltration Membranes by Electrospinning-Sintered Technology

Abstract

Perfluoropolymer membranes are widely used because of their good environmental adaptability. Herein, the ultrafine fibrous FEP porous membranes were fabricated with electrospinning-sintered technology. The effects of PVA content and sintering temperature on the fabricated membranes’ morphologies and properties were investigated. The results indicate that a kind of dimensionally stable network structure was formed in the obtained ultrafine fibrous FEP porous membranes after sintering the nascent ultrafine fibrous FEP/PVA membranes. The optimal sintering conditions were obtained by comparing the membranes’ performance in terms of membrane morphology, hydrophobicity, mechanical strength, and porosity. When the sintering temperature was 300 °C for 10 min, the porosity, water contact angle, and liquid entry pressure of the membrane were 62.7%, 124.2° ± 2.1°, and 0.18 MPa, respectively. Moreover, the ultrafine fibrous FEP porous membrane at the optimal sintering conditions was tested in vacuum membrane distillation with a permeate flux of 15.1 L·m−2·h−1 and a salt rejection of 97.99%. Consequently, the ultrafine fibrous FEP porous membrane might be applied in the seawater desalination field.

Recent Progress of the Preparation and Application of Electrospun Porous Nanofibers

“…The successful construction of this multifunctional membrane could provide inspiration for the design of high-quality films for numerous filtration applications. Chen et al [ 138 ] used a poly(tetrafluoroethylene-co-hexafluoropropylene) (FEP)/polyvinyl alcohol (PVA) blend solution for electrospinning to prepare fiber film and then sintered it under a N 2 atmosphere to obtain microfiber FEP porous films. When the weight ratio of PVA/FEP was 1:6, the sintering temperature reached 300 °C, and the sintering time was 10 min, the porous membrane showed strong hydrophobicity, a tiny pore diameter, and high porosity, which met the reasonable pore size of the filter membrane.…”