Hydrophilic nature and sorption-diffusion properties of nanocomposite hybrid polysulfone films

Abstract

Hybrid nanocomposite films containing silica (≥11.4 wt.%) or titania (≥18.8 wt.%) in the polymer matrix were prepared by the sol-gel method using the hydrolytic polycondensation of tetraethoxysilane and tetrabutoxysilane in a THF solution of aromatic polymer, polysulfone (PSF). The influence of the oxide nature and the film composition on the structure, the interaction of the polymer with oxides, hydrophilicity, and sorption-diffusion properties of the hybrid films were studied by FTIR spectroscopy, atomic force microscopy, dynamic light scattering, and a complex of other physicochemical methods. The absence of chemical or intermolecular hydrogen bonds between the polymer and oxide particles in the PSF films was shown. The average size of the oxides (SiO 2, ∼20 nm; TiO2, ∼90 nm) in the films and roughness of their surface (∼0.2-0.8 nm) were determined. The introduction of oxides into the polymer matrix increases the hydrophilic properties and the ability of the PSF films to swell in water; the diffusion coefficients of water and permeability of water vapor in the PSF films also increase. Titania also induces a more considerable change in the structure of the polymer matrix and more strongly affects the sorption-diffusion properties of the hybrid films in aqueous solutions of THF. All prepared nanocomposite films PSF/SiO2 and PSF/TiO2 are capable of extracting an organic component from aqueous solutions and can be used as sorbents and membrane films for the removal of organic substances from the aqueous medium. © 2012 Springer Science+Business Media New York.