Synthesis of conducting water-dispersible polyaniline particles and its template-guided patterning

Abstract

Organic conductors are a promising material for future electronics. Although, its processing is a big challenge. In this manuscript, we demonstrate micropatterning of polyaniline within the pores of a polycarbonate membrane to fabricate a device for a conductometric sensor. The aqueous dispersion of polyaniline particles was prepared by single pot oxidative polymerization of aniline monomer using dodecylbenzene sulfonic acid as a surfactant as well as a dopant, and the polyaniline from its aqueous dispersion was then precipitated within the pores of polycarbonate membrane by adding solvents of varying polarities. The phase diagram of precipitation was drawn by titrating the polyaniline dispersion with tetrahydrofuran solvent. The dispersion was characterized by Fourier transform infrared spectroscopy and UV-Vis spectroscopy, as well as a transmission electron microscope. The molecular weight of the synthesized polyaniline was measured by gel permission chromatography. The morphology of polyaniline has been compared through transmission electron microscopy in its dispersed form and after precipitation. Field emission scanning electron microscopy was used to see the growth of channel formation of precipitated polyaniline within the pores of the polycarbonate membrane. The electroactivity of the precipitated polyaniline was measured by in-situ conductance measurement as a function of the electrochemical state.