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Keywords:

  • conducting polymer;
  • hydroxamic acid;
  • metal complexes;
  • conductivity;
  • chemical and electrochemical polymerization;
  • polypyrrole

Abstract

The (N-pyrrolyl)1,1-methane dihydroxamic acid have been synthesized from its N-substituted ester group derivative, then chemically polymerized in the presence of oxidants such as ammonium persulphate and Iron(III) perchlorate for hydroxamic acid and ester groups derivatives, respectively. This compound and its ester group derivative was successfully electropolymerized by a cyclic voltammetry method. New functionalized polypyrrole films containing transition metal complexes have been prepared and studied. The strategy is based on the three-dimensional template effect of a metal center (CuII, NiII, CrIII, FeIII) able to entwine two and three end functionalized chelating ligand before or after polymerization. The used ligand consists of a methyl dihydroxamic acid bearing one pyrrole nuclei. The rigidity of the polymer matrix is sufficient to allow demetalation of the template center (by CN or SCN) without collapse of the three-dimensional structure. Such property is related to the expected complex topology of the material prepared. The organic backbone certainly contains interlocking rings and various network substructures. The polymer matrix thus keeps a little memory of the templating metal used for building it. Fe(III) ion turned out to be the most convenient template during the polymer electrosynthesis and seemed to lead to the most structured network. The various complexes obtained using electrochemical synthesis method display electrochemical properties analogous to those of the corresponding catenate in solution. All complexes in low oxidation states are remarkably stabilized by the entwined and entangled system. The conductivity of these polymers and it metal complexes were measured using four-probe method. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010