SOLID-STATE VOLTAMMETRY AND SELF-DIFFUSION DYNAMICS OF A LINEAR MONOTAGGED REDOX POLYMER - OMEGA-FERROCENECARBOXAMIDO-ALPHA-METHOXYPOLY(ETHYLENE OXIDE)

The synthesized title labeled polymer, Fc-MePEG, MW = 2590, analytically characterized as free of unlabeled PEO and of ferrocene monomer, dissolves LiC104 electrolyte and in dry undiluted form is both a polymer electrolyte and an electroactive phase. The microelectrode solid-state voltammetrically measured, center-of-mass self-diffusion coefficient for Fc-MePEG in its polymer melt, 1.3 X 10-8 cm2/s at 62 °C, is 3.4 times smaller than that for ferrocene monomer dissolved in unlabeled (MW = 2380) Me2PEG. Electron hopping is estimated to contribute less than 10% to the diffusion rates of Fc-MePEG and of monomer dissolved at 40-50 mM concentrations in unlabeled Me2PEG. At room temperature, where Fc-MePEG and Me2PEG are waxy solids, Dfc-McPeg is 3.9 X 10-12 cm2/s, 12 times smaller than that of monomer ferrocene, in Me2PEG, and which corresponds to a diffusion pathlength of ca. 110-200 nm during the electrochemical experiment. Dissolved in CH3CN or CH2Cl2, Fc-MePEG diffuses 8-10 times more slowly than ferrocene monomer which is consistent with transport as a random coiled sphere. © 1990, American Chemical Society. All rights reserved.