EFFECT OF THERMAL-TREATMENT ON THE ELECTROACTIVITY OF POLYANILINE

A series of polyaniline films have been coated on electrodes by chemic al and electrochemical means in order to investigate the thermal stabi lity of the electroactivity in air and nitrogen atmospheres. Polyanili ne was also synthesized chemically and cast as a membrane (thick film) . It was found that the electroactivity and conductivity of the films was stable up to 150 degrees C. Exposure to higher temperatures leads to a decrease in electroactivity and conductivity, although use of a n itrogen atmosphere had less effect on the properties. Thermogravimetri c analysis profiles confirmed that the polymer was stable to above 350 degrees C. The changes in the electroactivity may be attributed to mo rphological (annealing) effects in the polymer and to loss of moisture and dopant ions.