ION BINDING BY POLY(PYRROLE-CO-[3-(PYRROL-1-YL)PROPANESULFONATE]) THIN-FILMS

A biconductive polymer film, poly{pyrrole-co-[3-(pyrrol-1-yl)-propanesulfonate]} (PP-PS), capable of binding positive multiply charged complex ions such as Ru(NH3)6 3+ and Ru-(bpy)3 2+(bpy = 2,2'-bipyrldyl), is demonstrated. This study was designed with a view to glean quantitative details about this binding process and to provide comparisons with a composite polypyrrole-poly(styrenesulfonate) (PP-PSS) electrode. Electrochemical (voltammetric) and spectroscopic assay of these species within the copolymer film permitted estimation of their thermodynamic partitioning coefficients. The binding of Ru(NH3)6 3+ was more persistent and stable within the PP-PS film (no discernible loss for ~2 h after ion loading) than was that of Ru(bpy)3 2+. For both PP-PS and the PP-PSS analogue, only a fraction of the total sulfonate sites available was utilized for binding of a multiply charged Ion such as Ru(NH3)6 3+. © 1990, American Chemical Society. All rights reserved.