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Hybrid polyethersulfone-based ultrafiltration membranes were prepared by incorporating metal (Ag and Cu) and/or amine-functionalized mesostructured SBA-15 silica particles. The doping particles were included into the casting solution to obtain a total solids load of 3.6 wt% in the final membranes. The physicochemical characterization of particles and membranes showed a good dispersion of metals inside the mesoporous structure of silica as well as a reduced skin layer, higher pore interconnectivity, and a larger amount of pores in membranes doped with the hydrophilic fillers. Membrane surface was also slightly less hydrophobic in hybrid membranes. Membrane performance was significantly improved as result of considerable increase of water permeation without affect negatively the membrane selectivity. The organic antifouling properties were enhanced with significant permeability improvement without compromising membrane rejection performance. In addition to it, metal-loaded silica allowed preparing membranes with high antibacterial activity. The removal of colonies of Escherichia coli and Staphylococcus aureus was complete either on membrane surface or in the liquid in contact with membranes when exposed to a 1/500 nutrient broth medium for 20 h at 36 °C. The rate of metal release depended on metal speciation and represented a 0.1–0.6% of the total metal content of membranes. [ABSTRACT FROM AUTHOR]

New polyethersulfone (PES) ultrafiltration hybrid membranes were prepared by doping with different amine-functionalized mesostructured silica (SBA-15) particles added at low weight concentration (0.6% in the synthesis medium). 3-(aminopropyl) trimethoxysilane, N -(3-trimethoxysilylpropyl)ethylenediamine, and N -(3-trimethoxysilylpropyl)diethylenetriamine were used as amine precursors of the fillers obtained by co-condensation and denoted as SBA-15/Monoamine, SBA-15/Diamine, and SBA-15/Triamine, respectively. SBA-15 material functionalized with polyethylenimine was synthetized by hyperbranching polymerization with aziridine. Physicochemical characterization of fillers was achieved by nitrogen sorption, X-ray diffraction, TEM, dynamic light scattering, and elemental analysis. Membrane morphology was assessed in terms of overall porosity by water uptake and surface pore size distribution from FEG-SEM. Hydrophilicity of the membranes was determined by measuring water contact angle. Significant increase of porosity and hydrophilicity was found in all doped membranes, which exhibited substantial improve in water flux in comparison with neat PES membrane. Filtration experiments conducted with BSA protein aqueous solutions (1 g L −1 ) revealed that antifouling ability of doped membranes was gradually enhanced with amine functionalization, especially against reversible fouling. PES/SBA-15/Triamine appeared as the best specimen in both water flux and antifouling behavior with excellent long time permeation performance in repeated cleaning/filtration cycles. [ABSTRACT FROM AUTHOR]

Novel hybrid ultrafiltration membranes have been prepared by incorporation of mesostructured functionalized silica particles in polyethersulfone. Physico-chemical characterization of synthesized materials was accomplished to determine the textural and structural properties of particles by nitrogen adsorption–desorption and TEM. A successful functionalization of silica with amine and carboxylic groups was confirmed by means of MAS-NMR. Membrane surface morphology was studied in terms of pore size distribution, porosity and hydrophilicity, suggesting a great influence of mesostructured silica incorporation in polyethersulfone on the polymer matrix configuration. Membrane functions were significantly improved as a result of a considerable increase of water permeation without affecting negatively the membrane selectivity. The antifouling membrane properties were also enhanced, especially against irreversible fouling. Multi-run fouling tests of modified membranes confirmed the stability of permeation through membranes doped with mesostructured functionalized silica particles. [ABSTRACT FROM AUTHOR]