Cellulose acetate/poly(vinyl alcohol) and cellulose acetate/crosslinked poly (vinyl alcohol) blend membranes: preparation, characterization, and antifouling properties

Cellulose acetate (CA)/poly(vinyl alcohol) (PVA) blend membranes have been first prepared by non-solvent induced phase separation process. The pure water flux (PWF), hydrophilicity, and porosity increased with an increment in CA/PVA compositions up to 90/10. Then, polyvinyl pyrrolidone (PVP) as additive was added into the CA/PVA (90/10) casting solution. It was found that the PWF and porosity of CA/PVA/PVP blend membranes increased initially and then declined with the addition of PVP. Meanwhile, the effect of PVP content in CA/PVA blend membranes on fouling-resistant ability was studied using oil-in-water emulsion. The result indicated that all CA/PVA/PVP blend membranes had better antifouling property than CA/PVA membrane. If the PVA content in the casting solution increased to 20wt%, the fabricating of membrane was difficult because of the strong hydrophilicity and large swelling capacity of PVA. Therefore, PVA was first crosslinked with glutaraldehyde (GA) as the crosslinking agent, followed by in situ blended with CA and PVP to fabricating the CA/crosslinked PVA (CPVA) (80/20)/PVP blend membrane. The effect of GA and PVP content on hydrophilicity, morphology, and performance of CA/CPVA (80/20)/PVP blend membranes were also discussed in detail.