Synthesis, Characterization and Optical Properties of Oxidized Poly Vinyl Alcohol

Poly (viny1 alcohol) (PVA) was partially oxidized by alkaline KMnO4 with an average carbonyl percentage of 65 %. PVA's photo physicochemical properties before and after the oxidation (OPVA) were investigated. The FTIR spectrum of OPVA revealed a new band at 1645 cm(-1), corresponding to the carbonyl group and the XRD pattern reflecting an increase in the degree of crystallinity. Unlike pristine PVA, the UV-vis absorption spectra displayed the most attractive results through OPVA absorption in UV and visible regions. Furthermore, the photoluminescence spectra of PVA membrane exhibited a narrow emission at 338 nm, whereas the OPVA membrane showed blue emission at 415 nm. The proton conductivity increased from 1.5 mScm(-1) in PVA to 11.1 mScm(-1) in OPVA at 70 degrees C. Thus, the presence of both hydroxyl and carbonyl groups in OPVA results in the formation of strong hydrogen bonding that facilitate proton transfers along the hydrogen-bond network.