SPECTROSCOPIC, STRUCTURAL AND TRANSPORT-PROPERTIES OF CONDUCTIVE POLYANILINE PROCESSED FROM FLUORINATED ALCOHOLS

Studies of PANI protonation in fluorinated alcohols are presented. Thr ee solvents have been tested, namely 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP), 1,1,1,3,3,3-hexafluoro-2-phenyl-2-propanol (HFPP), and 1,1,1, 3,3,3-hexafluoro-2-(p-tolyl)-propanol (HFTP). It has been demonstrated that the degree of the broadening of the NIR absorption, which can be considered as a measure of polaron delocalization, depends strongly o n the selection of an appropriate protonating agent-solvent couple. Se veral couples, giving spectra similar to that reported for PANI(CSA)(0 .5) in m-cresol, have been found. Processing of PANI from HFIP solutio ns leads to films with improved PANI chains stacking order as evidence d by X-ray diffraction studies. The films exhibit metallic type of con ductivity down to 200 K. The temperature dependence of the conductivit y over the whole temperature range studied has been fitted using a com bination of a metallic and hopping contribution in the frame of a hete rogeneous disorder picture of PANI.