Effect of aniline formaldehyde resin on the conjugation length and structure of doped polyaniline: Spectral studies

Abstract

A DBSA (n‐dodecylbenzene sulfate)‐complexed aniline formaldehyde [AF(DBSA)1.0] was successfully synthesized with excess aniline (compared with formaldehyde) in the presence of n‐dodecylbenzene sulfonic acid (HDBSA), which was complexed with aniline monomer before polymerization. The resin was carefully characterized with 1H and 13C NMR, electron spectroscopy for chemical analysis, and Fourier transform infrared and was demonstrated to be a polymer in which anilines were all complexed with HDBSA and became anilinium salts. A drastic decrease of the maximum absorption wavelength (ultraviolet–visible spectra) of DBSA‐doped polyaniline [PANI(DBSA)0.5] was found when AF(DBSA)1.0 was mixed, and this resulted from the reduced conjugation length. A similar effect on PANI(DBSA)0.5 was found when free HDBSAs were mixed with PANI(DBSA)0.5. Visual inspection with an optical microscope revealed that PANI(DBSA)0.5/AF(DBSA)1.0 gave uniform morphologies in various compositions, showing possible miscibility for this system. X‐ray diffraction patterns of PANI(DBSA)0.5/AF(DBSA)1.0 showed that the layered structure of PANI(DBSA)0.5 was still present but became shorter in the polyblend because of the presence of AF(DBSA)1.0. Solid‐state 13C NMR spectra revealed that the reduced conjugation length was derived from the interaction of alkyl groups between HDBSA, complexed DBSA, and dopant DBSAs. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3116–3125, 2005

PANI-derived polymer/Al2O3 nanocomposites: synthesis, characterization, and electrochemical studies

“…The first one appears at 0.59/0.31V, which results in a potential peak separation (∆E p ) close to 280mV; the second process is observed at 0.94/0.67V and gives an ∆E p value of 270mV. These redox processes are attributed to leucoemeraldine/emeraldine and emeraldine/pernigraniline transitions, respectively [43,44]. With presence of the 2ClAni, we observe one redox peak.…”

Synthesis and characterization of a novel proton‐exchange membrane for fuel cells operating at high temperatures and low humidities

“…[22][23][24] However, crystallinity can be found if aniline is replaced by ptoluidine, for which only ortho-ortho polymerization is possible. The WAXD patterns of PTF resins of different monomer ratios are shown in Figure 3.…”

“…Only Figure 1(c) demonstrates 3422 cm 21 due to the presence of the stretching À ÀOH group obtained from excess formaldehyde, which can form the etheryl backbone and hydroxyl chain ends and accounts for the better water solubility. 22 These hydroxyl chain ends allow us to perform any modification of the PTF membrane, such as changes in the methanol-barrier property and the attachment of hydrophobic groups. The assignments of the infrared spectrum are listed in Table I.…”

Effect of nonconjugated polymers on the conjugation length and structure of poly(3‐octylthiophene) in ternary polymer blend

“…Therefore, the miscibility may come from either the interaction of methylene of P3OT/ PMMA or P3OT/EVA20, which was also found in the conducting polymer blend based on polyaniline doped with long alkyl sulfonic acids. 35,36 …”