Relaxation transitions in thermally treated polyaniline films

Thermally treated films of polyaniline-emeraldine base (PANI-EB) cast from NMP solution were studied by using differential scanning calorimetry. Dependence of the thermodynamic parameters of the relaxation transitions on temperature and annealing period as well as the effect of the thermal history of the samples upon the crosslinking processes were investigated. For the first time DSC analysis of PANI-EB films after prolonged ageing was performed. It was found that relaxation transitions can be registered only for crosslinked PANI-EB. The crosslinking processes proceed both upon short-time heating of the polymer studied over 80°C and during long-time storage at room temperature.