Evaluation of Polyurethane-Based Membrane Matrices for Optical Ion-Selective Sensors

Publisher Website
Google Scholar
Abstract
Plasticized thin films of polyurethane (PU) mixed with poly(vinyl chloride)(PVC) or a terpolymer of poly(vinyl chloride)/(vinyl acetate)/(vinyl alcohol) (PVA) are examined as membrane matrices for the preparation of reversible optical ion sensors. Optical sensors for Na+, NH4 +, Cl− and ClO4 − are prepared by casting thin films of the polymer mixtures (PU/PVC (1:1 wt) and PU/PVA (4:1 wt)) containing appropriate ion carriers and pH chromophores on glass slides. The optical response properties of these membranes is essentially the same as conventional pure PVC membranes reported in the literature. However, significantly enhanced membrane adhesion to glass or silicon wafer surfaces is observed using the polyurethane based matrices, making them more suitable than PVC for use in the development of solid-state optical ion sensing devices.