AN INSITU RAMAN-STUDY OF THE ELECTROCHEMICAL DOPING OF ORIENTED DURHAM POLYACETYLENE

The results of a Raman study on electrochemically Na+ doped oriented Durham polyacetylene are presented. The spectral changes observed suggest that low doping levels cause an effective shortening of the conjugated length. Doping to 3 mol% Na+ gives a two-phase behaviour for the doped polymer. Beyond 6 mol% the spectra recorded are consistent with a delocalized structure. An additional Raman band at 1268 cm-1 is assigned to a carbon-carbon stretching mode which has significant double-bond character. Following an electrochemical doping-undoping cycle the polymer does not return to the pristine state but shows signs of either polymer degradation or residual dopant ion remaining in the material.