Year: 1993
Type: dissertation
Abstract: Polymers with pendant selenium coronands, 1, 5-diselenacyclooctane (8Se2) and 1, 5, 9, 13-tetraselenacyclohexadecane (16%) have been prepared by free radical polymerization of selenium coronands derivatized with acryloyl groups.Copolymers were also prepared by copolymerization of methyl acrylate with 3, 7-diselenacyclooctyl acrylate.These polymers and copolymers were characterized by l H NMR, l3C NMR, IR and W-visible spectroscopy, mass spectrometry, atomic absorption spectroscopy, gel permeation chromatography, differential scanning calorimetry and cyclic voltammetry.W-visible spectroscopy has been used to monitor interactions between the polymers and different metal ions.Significant interactions were observed with eleven metal ions for the polymer containing 8Se2, whereas polymers containing 16% showed interactions only with C U ~+ , T&+, Fe3+, and Pd2+.These interactions are attributed to complexation.The polymerCu complexes have been characterized by atomic absorption spectroscopy.Polymers with pendant selenium coronands exhibit a rich redox chemistry, much like the monomeric selenium coronands.These polymers can be oxidized both chemically (NOBF4) and electrochemically.Cyclic voltammetric studies suggest the presence of inter-and intra-selenium coronand electron transfer processes.Relative to monomeric selenium coronands, irreversible reactions between oxidized species and neutral ligands are suppressed by tethering the coronands to polymer chains.This behavior is observed for the polymers in solution and coated on electrodes (polymer modified electrodes).The phenomenon represents partial control of the fate of reactive species by steric constraint.Polymer-coated electrodes were tested for their ion-selective properties.A linear relationship of potential versus concentration was obtained for cu2+ ion.
Source: Summit (Simon Fraser University)
Author: Hanbin Hu
Language: English
Subfield: Organic Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W166170770