Electrochemical synthesis of fluorinated polyanilines

A set of fluoro-functionalized polyaniline conducting polymers was synthesized by cyclic scanning of the potential from acidic solutions containing aniline and 2-fluoroaniline monomers. The monomer feed ratio was varied to modulate the composition of the synthesized materials. The fluorination level of the copolymers was quantified from X-ray photoelectron spectroscopy. The upper inversion potential of the cyclic scans was proved as a suitable tool to tune the fluorination level, as the reactivity of the growing chains depends strongly on that experimental parameter. We found that terminal fluorinated anilines present a reactivity for homocoupling 5 times lower than for heterocoupling, independently of the limiting potential. Conversely, aniline terminal groups present a reactivity strongly dependent on the limiting potential, favoring the heterocoupling reactions at high inversion potentials. The maximum fluorination level of polyaniline rings achieved is about 75%.