Spectroscopic investigation of thermal treatment of doped polypyrrole

摘要: The results of a UV/VIS spectroscopic investigation thin films oxidized polypyrrole doped with p-toluenesulfonate, dodecylsulfate or copper phthalocyanine tetrasulfonate anions immediately after electrochemical synthesis and during heat treatment are presented. The absorption bands in the resulting spectra were identified electronic transitions polarons, bipolarons transverse as follows: below ca. 1.4 at 1.8 eV both attributed to sum polarons transverse bipolarons, band 2.44–2.5 band around 3.2–3.6 gap transition polypyrrole. identity above 3.8 remains uncertain. absorbance changes collected sample aging were explained result rearrangement structure. main processes acting aging interchain conversion into bipolarons interaction yielding bipolarons. spectral changes induced by heating 80 °C seem be caused mainly an dissociation their slower intrachain recombination polypyrrole neutral form. structural is very slow process because not stable even 35 h. taking place structure cooling opposite those but they only partially reversible magnitude. samples p-toluenesulfonate exhibited similar behavior whereas extraordinary owing liquid-like solid-state micellar magnitudes spectra showed that relatively small proportion the species present within influenced these processes.