Electrochemical and chemical synthesis and characterization of sulfonated poly(3,4-ethylenedioxythiophene): A novel water-soluble and highly conductive conjugated oligomer

Electrochemical and chemical polymerization of a 3,4-ethylenedioxythiophene derivative bearing a sulfonate group (EDTS) is reported. The electrochemical polymer, poly(EDTS), which is very soluble in water, has been produced both from acidic, water, resulting in the solution form, and from acetonitrile using additional perchloric acid in 1:1 ratio to the monomer, resulting in the production of polymer films. Both forms were characterized by cyclic voltammetry, UV-Vis spectroscopy, EQCM analysis, MALDI-TOF MS and conductivity measurements, and show high conductivity (0.5-10 S.cm -1 ) and high solubility in water (>10%). Poly(EDTS) was also prepared by chemical polymerization with Fe(OTs) 3 in water to yield once more a water-soluble and conductive (1-5 S.cm -1 ), polymer.