EPR study of polyaniline highly doped by p-toluenesulfonic acid

Solid-state NMR and EPR study of fluorinated carbon nanofibers

“…Interactions between carbon DB and paramagnetic oxygen adsorbed on the surface of CNFs could modify the magnetic properties. This behavior has been already observed for (CF) n and (C 2 F) n graphite fluorides [15,16] and in conducting polymers such as polypyrrole [35], protonated emeraldine form of polyaniline [36,37] and of polyaniline sulfonate-based hybrid nanocomposite [38]. In order to verify this hypothesis in the present case, EPR spectra of C-480 and D-480 were recorded after out-gassing for one hour at 120 1C and 2 h at 300 1C under secondary vacuum (Figs.…”

New Insight into Organic Metal Polyaniline Morphology and Structure

“…We had only been able to measure the macroscopic conductivity which is around 5 S/cm for the raw polymer powder (in pressed pellet form) at the insulator side of the IM transition, and above 100 S/cm up to 600 S/cm for the metallic polyaniline [12]. Later, in cooperation with two other research groups and using electron spin resonance spectroscopy (EPR), we succeeded to find the intrinsic conductivity within the metallic core to be in the order of 60,000 S/cm [13]. This is at least 100 times more than we can macroscopically measure.…”

EPR study of spin interactions in the poly(3-dodecylthiophene): Fullerene/polyaniline: p-toluenesulfonic acid composite

“…Para magnetic susceptibility was determined by double integration of individual lines of the EPR spectra recorded well away from their saturation conditions. All relaxation parameters of charge carriers were determined separately using the method of continuous wave saturation of EPR spectra [8]. The processing and simulation of the EPR spectra were performed using the program OriginLab.…”

“…Polarons gener ated by doping PANI are characterized by high stabil ity of their basic parameters owing to the conforma tional stability of the spin state of the majority of poly anilines. Studies of PANI : pTSA revealed increased accessibility of polarons for foreign spins, in particular, molecular oxygen diradical [7,8]. The exchange inter action of both spin ensembles in that case is deter mined by the properties of the PANI polymer matrix and the precession frequency of the polaron spins.…”