The profiling measurements on metal ion distribution in CTA polymeric inclusion membranes by Rutherford backscattering spectrometry

Polymer inclusion membranes based on cellulose triacetate polymer, containing 2-nitrophenyloctyl ether as plasticizer and the crown dioctylphosphyl (TOPO) as a fixed carrier were prepared were studied by backscattering spectrometry technique to measure the distribution of the metal ions across the membrane using (p, α) beam from the 3.75 MV VDG accelerator at Nuclear Research Center (CRNA). The sample was mounted at normal incidence with respect to the beam in a scattering chamber of 80 cm diameter. Simulation is done by SIMNRA software. The results of this study suggest that RBS may offer advantages in a wide range of membrane materials analysis applications. The ability to accurately measure the thickness and composition of thin polymeric layers using RBS offered a means of analyzing complex structures in which metals are adsorbed. RBS provided an accurate tool to determine the elemental composition, thickness and roughness of the membrane. The oxygen-to-carbon and the molybdenum to phosphor ratio obtained for CTA membranes were obtained. Changes in physico-chemical properties of the polymers were assessed by model fitting of the RBS spectra, oxygen was found to be the most unstable element in this investigation. (author)