Synthesis, characterization, and comparison of self‐doped, doped, and undoped forms of polyaniline, poly(o‐anisidine), and poly[aniline‐co‐(o‐anisidine)]

Abstract

Polyaniline (PANI), poly(o-anisidine), and poly[aniline-co-(o-anisidine)] were synthesized by chemical oxidative polymerization with ammonium persulfate as an oxidizing reagent in an HCl medium. The viscosities, electrical conductivity, and crystallinity of the resulting polymers (self-doped forms) were compared with those of the doped and undoped forms. The self-doped, doped, and undoped forms of these polymers were characterized with infrared spectroscopy, ultraviolet-visible spectroscopy, and a four-point-probe conductivity method. X-ray diffraction characterization revealed the crystalline nature of the polymers. The observed decrease in the conductivity of the copolymer and poly(o-anisidine) with respect to PANI was attributed to the incorporation of the methoxy moieties into the PANI chain. The homopolymers attained conductivity in the range of 3.97 ϫ 10 Ϫ3 to 7.8 S/cm after doping with HCl. The conductivity of the undoped forms of the poly[anilineco-(o-anisidine)] and poly(o-anisidine) was observed to be lower than 10 Ϫ5 J/S cm Ϫ1. The conductivity of the studied polymer forms decreased by the doping process in the following order: self-doped 3 doped 3 undoped. The conductivity of the studied polymers decreased by the monomer species in the following order: PANI 3 poly[aniline-co-(o-anisidine)] 3 poly(o-anisidine). All the polymer samples were largely amorphous, but with the attachment of the pendant groups of anisidine to the polymer system, the crystallinity region increased. The undoped form of poly[aniline-co-(o-anisidine)] had good solubility in common organic solvents, whereas doped poly[aniline-co-(oanisidine)] was moderately crystalline and exhibited higher conductivity than the anisidine homopolymer.

Preparation and characterization of polypyrrole/dextran sulphate composite: its electrochemical and thermal behaviors

“…Among conducting electroactive polymers, polypyrrole (PPy) and its derivatives have received a great attention due to its high electrical conductivity, good environmental stability, relative ease of synthesis and good redox reversibility [2,3]. Conductive and biocompatible properties of PPy make it a promising material for electronic capacitor [4], anticorrosion coating [5], electrochemical and biosensors [6,7]. However, polypyrrole and other conducting electroactive polymers are limited in practical use due to their very sensitive structure and insolubility [8].…”

Characterization of Poly(o-methoxyaniline) Emeraldine-base form obtained at different time neutralization

“…The use of the Intrinsically Conducting Polymers (ICPs) has been hampered by the fact that many of these materials are insoluble and infusible because of the delocalized p bonds along their macromolecular chains [1]. Polyaniline (PANI) has always been regarded as an intractable material due to its poor solubility in common organic solvents.…”

Synthesis and characterization of poly(m-aminophenol)-succinat

“…PANI and its derivatives can be used as electronic or electro-conductive materials in a wide variety of application areas for instance: cell electrode materials, fabrication of secondary batteries, electrochromic display, electromagnetic shielding materials, various sensors and gas-separating membranes. [1][2][3][4][5][6] The great difficulty in technological application of PANI is due to its low solubility. Unsubstituted PANI in salt form is insoluble in common organic solvents.…”