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DOE OSTI · 1068957

Conducting Polymer: Polyaniline

Abstract

Electronically conductive polymers composites have gained tremendous attention over the last decade due to their unique properties for various applications such as rechargeable batteries, electromagnetic shielding, sensors and electronic devices. Polyaniline has been one of the most popular conducting polymer for the past fifty years. It has low density, good environmental stability, moderate conductivity and is considered as one of the most promising electrically conducting polymers. Polyaniline exists in three forms (Fig. 1): Leucoemeraldine, pernigraniline, and emeraldine. Leucoemeraldine is the fully reduced state and is white/clear colorless. Pernigraniline is the fully oxidized state with imine links instead of amine links and is blue/violet. The emeraldine form of polyaniline, often referred as emeraldine base (EB), is neutral and blue. When EB is doped, it turns green and is called emeraldine salt (ES) with the imine nitrogens protonated by an acid. EB delocalizes to the trapped diiminoquinone-diaminobenzene state, which is highly electrically conducting. Emeraldine base is regarded as the most useful form of polyaniline due to its high stability at room temperature. In this experiment, EB is doped with two different protonic acids (Fig. 3), 2-Acrylamido-2-methylpropane sulfonic acid (AMPSA) and camphorsulfonic acid (CSA), to compare the effectiveness of the dopants. The doped EB (ES) is later casted into films with a new resin to produce new polyaniline conductive composites and their conductivities are being studied.

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Lin, Terri C.. 2013-03-18. Conducting Polymer: Polyaniline. https://doi.org/10.2172/1068957

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