ION-BINDING BY POLY [4-(PYRROL-1-YLMETHYL)BENZOIC ACID] THIN-FILMS

Thin functionalized polypyrrole films exhibiting cation-exchange abili ty have been synthesized by oxidative electropolymerization of a pyrro le-carboxylic acid monomer on indium tin oxide (ITO) electrodes. The i ncorporation of hexaamineruthenium, tris(1,10-phenanthroline)iron and ,20-tetrakis(1-methyl-4-pyridyl)-21H,23H-porphyrin cations was easily achieved in preformed films. Results from these incorporation experime nts allowed the determination of the pK(a) of the polymeric material a nd its exchange capacity. The latter was estimated at 4.5 molar equiv. kg(-1), which is comparable to those of regular cation-exchange resin s.