Formulation, Characterization, and Sensing Applications of Transparent Poly(vinyl alcohol)−Polyelectrolyte Blends

Several new optically clear polymer blends have been formulated for selectively incorporating solution-phase anions and cations. In all of the blends poly(vinyl alcohol) was the host matrix and it was cross-linked with glutaraldehyde to entrap polyelectrolytes including poly(acrylic acid), Nafion, poly(diallyldimethylammonium chloride), poly(vinylbenzyltrimethylammonium chloride), and poly(styrenesulfonic acid). [Ru(BiPy)3]2+ and Fe(CN)63- were used as prototypical analytes to study the ion-exchange properties of the new blends. The thicknesses of spin-coated thin films of the blends were variable over a wide range (0.70 μm being typical), as determined by an optical interference method. Thin film coatings of three of the blends were optimized for single-step covalent coating on activated oxide surfaces. Two silane coupling agents, 3-glycidoxypropyltrimethoxysilane and 3-aminopropyltriethoxysilane, were used to covalently attach these three blends to glass and ITO-coated glass surfaces. The potential use ...