A Comparison Between Fresh and Thermally Aged Polyaniline Prepared by Different Approaches: On the Conductivity Under High Pressure

摘要

Since their discovery to date, electrically conductive organic polymers (ECOPs) have been extensively studied [1-3]. Among them polyaniline (PANI) is unique for its doping/dedoping mechanism, easy preparation, low cost and air stability. Although polyaniline can exist in different oxidation states, only the emeraldine salt (ES, half-oxidated and half-protonated form, Fig. 1) shows electrical conductivity. The conductivity of ES depends on numerous factors, such as molecular weight, morphology, size, crystallinity and kind of dopants. Some of these parameters can be monitored during the reaction, choosing properly the reaction conditions (i.e. medium, temperature, kind of oxidant and acid), or after the reaction by specific treatments (i.e. change of acid dopant, degree of crystallinity) [4, 5].