Ion binding by poly [4-(pyrrol-1-ylmethyl)benzoic acid] thin films

Abstract

This functionalized polypyrrole films exhibiting cation-exchange ability have been synthesized by oxidative electropolymerization of a pyrrole–carboxylic acid monomer on indium tin oxide (ITO) electrodes. The incorporation of hexaamineruthenium, tris (1, 10-phenanthroline)iron and 5,10,15,20-tetrakis(1-methyl-4-pyridyl)-21H,23H-porphyrin cations was easily achieved in preformed films. Results from these incorporation experiments allowed the determination of the pK_a of the polymeric material and its exchange capacity. The latter was estimated at 4.5 molar equiv. kg^–1, which is comparable to those of regular cation-exchange resins.