Fabrication of Low-Fouling Ultrafiltration Membranes Using a Hydrophilic, Self-Doping Polyaniline Additive

Abstract

A simple, scalable method for fabricating fouling-resistant ultrafiltration membranes is described. A self-doped, sulfonated form of polyaniline was blended into polysulfone (PSf) ultrafiltration (UF) membranes to enhance hydrophilicity and fouling resistance. Polyaniline in its base form was sulfonated with fuming sulfuric acid, yielding sulfonated polyaniline (SPANi) with a degree of sulfonation of ∼0.5 confirmed by XPS. The SPANi polymer was dedoped and dissolved in a solution of polysulfone in N-methylpyrollidone at varying concentrations. During phase inversion to form membranes, SPANi is redoped and precipitated within the PSf membrane films in a facile one-step process. Composite membranes containing increasing amounts of SPANi were compared to the pure PSf membranes to determine changes in performance, hydrophilicity, and antifouling characteristics. The composite membranes exhibit fluxes similar to those of the pure PSf membrane and maintain rejection properties similar to those of current UF membranes. Captive bubble contact angle measurements and atomic force microscopy suggest increasing membrane hydrophilicity with increasing SPANi content. During flux decline and recovery experiments, SPANi/PSf composite membranes exhibited higher flux recovery than a pure PSf membrane, with the best performing membrane regaining 95% of its original flux after being washed with deionized water, demonstrating a high resistance to irreversible fouling.

Zwitterionic chitosan–silica–PVA hybrid ultrafiltration membranes for protein separation

“…The membrane Z-4 shows a strong OAH stretch at 3334 cm À1 due to the presence of CAOH and bound water [10]. The absorption bands at 2942 and 2914 cm À1 correspond to the stretching of ACH 2 groups, and that at 1637 cm À1 is related to the CAN stretching in AN + (CH 3 ) 3 groups [18].…”

“…However, the ultrafiltration membranes are often fouled by nonspecific proteins which are adsorbed on the surface of membranes though hydrophobic and electrostatic interactions [9,10].…”

Modification of membrane surfaces via microswelling for fouling control in drinking water treatment

“…Membrane fouling is influenced, to a large extent, by the surface chemistry and morphology. Pretreatment of polymeric materials before membrane fabrication (e.g., sulfonation or carboxylation [7,8]) and in situ treatment during membrane fabrication (e.g., in situ polymerization [9]) usually involve new materials. It is relatively difficult and costly to bring completely new and specially designed polymers into membrane manufacturing.…”

Silicificated polymer arrays based on a strong adhesive polymer for antifouling coatings

“…Here we introduce a novel approach for the preparation of hydrophobic coatings with antifouling properties. Polyaniline is utilized in chemistry, physics and material science, and it has a very good chemical stability . Polyaniline‐based epoxy and alkyd coatings have been evaluated for their antifouling properties.…”