title: Electrochemical evidences and consequences of significant differences in ions diffusion rate in polyacrylate-based ion-selective membranes.
abstract: The origin and effect of surface accumulation of primary ions within the ion-selective poly(n-butyl acrylate)-based membrane, obtained by thermal polymerization, is discussed. Using a new method, based on the relation between the shape of a potentiometric plot and preconditioning time, the diffusion of copper ions in the membrane was found to be slow (the diffusion coefficient estimated to be close to 10(-11) cm(2) s(-1)), especially when compared to ion-exchanger counter ions--sodium cations diffusion (a diffusion coefficient above 10(-9) cm(2) s(-1)). The higher mobility of sodium ions than those of the copper-ionophore complex results in exposed ion-exchanger role leading to undesirably exposed sensitivity to sodium or potassium ions.
authors.affiliation: Department of Chemistry, Warsaw University, Warsaw, Poland.
authors.forename: Emilia
authors.initials: E
authors.lastname: Woźnica
authors.forename: Józef
authors.initials: J
authors.lastname: Mieczkowski
authors.forename: Agata
authors.initials: A
authors.lastname: Michalska