Spectroscopic characterization of oligoaniline microspheres obtained by an aniline-persulfate approach.
This paper investigates the structure of the products obtained from the polymerization of aniline with ammonium persulfate in a citrate/phosphate buffer solution at pH 3 by resonance Raman, NMR, FTIR, and UV-vis-NIR spectroscopies. All the spectroscopic data showed that the major product presented segments that were formed by a 1,4-Michael reaction between aniline and p-benzoquinone monoimine, ruling out the formation of polyazane structure that has been recently proposed. The characterization of samples obtained at different stages of the reaction indicated that, as the reaction progressed, phenazine units were formed and 1,4-Michael-type adducts were hydrolyzed/oxidized to yield benzoquinone. Raman mapping data suggested that phenazine-like segments could be related to the formation of the microspheres morphology.
Departamento de Química Fundamental, Instituto de Química, Universidade de São Paulo, CP 26077 CEP 05513-970, São Paulo, SP, Brasil.
Daniela C
DC
Ferreira
José R
JR
Pires
Marcia L A
ML
Temperini
D000645:Ammonium Sulfate / Q000737:chemistry*; D000814:Aniline Compounds / Q000737:chemistry*; D016227:Benzoquinones / Q000737:chemistry; D019343:Citric Acid / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D008863:Microspheres; D010084:Oxidation-Reduction; D010710:Phosphates / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman
D000814:Aniline Compounds; D016227:Benzoquinones; D010710:Phosphates; C416807:polyaniline; C031276:ammonium peroxydisulfate; D019343:Citric Acid; C004532:quinone; C023650:aniline; D000645:Ammonium Sulfate