Functionalization of polypyrroles with acids and beta-diketones as complexing groups. Part 2: electrochemical growth of polypyrrole into hybrid zirconium oxopolymer sol/gel coatings

New hybrid materials were prepared by a sol-gel route from zirconium propox ide and functionalized polypyrroles bearing a complexing group (carboxylic acid or beta -diketone). Formation of polypyrroles in the gel deposited on an indium tin oxide (ITO) electrode was performed electrochemically in aque ous media. The optimal conditions for the preparation of stable sols were d etermined, as well as the deposition conditions to obtain reproducible tran sparent uniform coatings in which electropolymerization was possible. The x erogels as well as the composites after polymerization were analyzed with t he help of optical microscopy (OM), scanning electron microscopy (SEM) and X-ray fluorescence. The electrochemical characteristics of the composites w ere investigated by cyclic voltammetry and their adherence evaluated. From the polymerization rate and simple assumptions, the rate constant for pyrro le polymerization inside the gels has been evaluated.