Enhanced conductivity of polyaniline in the presence of nonionic amphiphilic polymers and their diverse morphologies

Poly(ethylene oxide) (PEO) and its copolymers have excellent affinity for protons and contribute to proton transfer. In the present study, PEO and its copolymers, poly[(ethylene oxide)(20)-(propylene oxide)(70)-(ethylene oxide)(20)] (EO20PO70EO20, P123) and poly[(ethylene oxide)(106)-(propylene oxide)(70)-(ethylene oxide)(106)] (EO106PO70EO106, F127), have been found to significantly enhance the conductivity of polyaniline (PANI). After introducing these polymers, the conductivity of PANI is markedly promoted more than two orders of magnitude compared to that of PANI without additives, from 5.2 to 667 S/m. The molecular weight of PEO affects the conductivity of PANI/PEO. The mechanism by which these amphiphilic polymers are beneficial to the conductivity of PANI is studied experimentally and theoretically. The PANI/P123 prepared in the presence of PEO block copolymer shows gradually varying morphologies containing leaflike sheets, rodlike particles, and uniform chestnutlike sphere particles. This is similar to the morphology change of micelles with surfactant concentration. PEO, P123, and F127 are further found to have a positive effect on PANI as a material for sensors or supercapacitors, since high specific capacity and fast response rate are desired qualities in sensors and supercapacitors. (c) 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45547.