Novel Poly(vinyl alcohol)-tetraethoxysilane hybrid matrix membranes as oxygen barriers†

Novel type of membranes based on poly(vinyl alcohol) crosslinked with tetraethoxysilane have been prepared by solution casting and solvent-evaporation method. The membranes thus formed were characterized by Fourier transform infrared spectroscopy (FTIR) to study the chemical interactions, X-ray diffraction (XRD), and thermogravimetry (TGA) to investigate morphological and thermal properties. Membranes were prepared in two different thicknesses (30 and 55 μm) and used for measuring the oxygen permeability under varying feed pressures (maintaining the desired pressure differential across the membrane) in the range from 1 to 50 kg/cm2 pressure. Oxygen permeability of the membranes ranged from 0.0091 to 1.6165 Barrer for 30 μm and 0.0305 to 0.1409 Barrer for 55-μm thick membranes by increasing the feed pressures on the feed side. Except at 50 kg/cm2 pressure, the observed oxygen permeability values are almost close to total permeability. Membranes of this study could be useful as oxygen barriers for applications in food packaging industries. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 273–278, 2007