Article ID Journal Published Year Pages File Type
623279 Desalination 2014 7 Pages PDF
Abstract

•FEP particles brought about interfacial microvoids in the PVDF/FEP blend membrane.•FEP brought about the improvement of hydrophobicity and permeability.•The cast solution exhibited good Newtonian flowing property which the n is 0.903.

Polyvinylideneflouride (PVDF)/poly(tetrafluoroethylene-co-hexafluoropropylene) (FEP) blend flat-sheet membranes were fabricated by the immerged phase-inversion method. Micro–nanometer scale FEP particles were introduced into PVDF/N,N-dimethylacetamide (DMAc) casting solution. Effects of FEP content on the rheology behavior of casting solution and performances of PVDF/FEP blend membranes were investigated respectively. Results shown that: (1) With FEP content increasing, the viscosity of casting solution decreased while the value of non-Newtonian index n increased. When FEP content was 60 wt.%, the value of n reached as high as 0.903 which demonstrated that the casting solution exhibited good Newtonian flowing property; (2) with FEP content increasing, the porosity and permeability of blend membranes increased obviously while the liquid entrance pressure (LEP) decreased. Blend membranes' cross-section morphologies shown that the increase in FEP content aided the formation of a larger and deeper finger-like pore structure; and (3) with FEP content increasing, mechanical strength of blend membranes decreased while the water contact angle increased at first then decreased.

Related Topics
Physical Sciences and Engineering Chemical Engineering Filtration and Separation
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