Abstract
The paper is focused on oxidative polymerization of aniline proceeding in an acid medium with a strong oxidant; formation of polyaniline (PANI) granular structures in different steps of the synthesis was studied. The relationship between the processes of self-organization of the growing polymer into supramolecular structures and the steps of molecular synthesis has been revealed. It was shown that during the induction period (the initial synthesis step), insoluble non-conducting products are formed. They are characterized by the absorption band at 430 nm corresponding to the wavelength of the phenazinium cation radical peak. In the second step, the polymer chain growth, conducting PANI granules with the diameter of 50 nm were obtained. These granules consist of spherical particles with the diameter as small as several nanometers. Then, the granule dimensions increased to 200 nm due to the growth of the spheres; the sphere diameter reached 20 nm. The number of spheres in a granule remained constant. Both precipitate and PANI film consist of common structural elements, polymer spheres, organized into granules and larger structures. Suppression of the polymer chain growth leads to the formation of non-conducting aniline oligomers which are self-organized into large particles with fractal structure. To describe the self-organization processes of a growing polymer chain, the diffusion-limited aggregation mechanism was used.
[1] Babayan, V., Kazantseva, N. E., Moučka, R., Sapurina, I., Spivak, Yu. M., & Moshnikov, V. A. (2012). Combined effect of demagnetizing field and induced magnetic anisotropy on the magnetic properties of manganese-zinc ferrite composites. Journal of Magnetism and Magnetic Materials, 324, 161–172. DOI: 10.1016/j.jmmm.2011.08.002. http://dx.doi.org/10.1016/j.jmmm.2011.08.00210.1016/j.jmmm.2011.08.002Search in Google Scholar
[2] Bhattacharjya, D., & Mukhopadhyay, I. (2012). Controlled growth of polyaniline fractals on HOPG through potentiodynamic electropolymerization. Langmuir, 28, 5893–5899. DOI: 10.1021/la30061841. http://dx.doi.org/10.1021/la3006184Search in Google Scholar
[3] Blinova, N. V., Stejskal, J., Trchová, M., Ćirić-Marjanović, G., & Sapurina, I. (2007). Polymerization of aniline on polyaniline membranes. The Journal of Physical Chemistry B, 111, 2440–2448. DOI: 10.1021/jp067370f. http://dx.doi.org/10.1021/jp067370f10.1021/jp067370fSearch in Google Scholar
[4] Ding, Z. F., Sanchez, T., Labouriau, A., Iyer, S., Larson, T., Currier, R. P., Zhao, Y. S., & Yang, D. L. (2010a). Characterization of reaction intermediate aggregates in aniline oxidative polymerization at low proton concentration. The Journal of Physical Chemistry B, 114, 10337–10346. DOI: 10.1021/jp102623z. http://dx.doi.org/10.1021/jp102623z10.1021/jp102623zSearch in Google Scholar
[5] Ding, Z. F., Yang, D. L., Currier, R. P., Obrey, S. J., & Zhao, Y. S. (2010b). Polyaniline morphology and detectable intermediate aggregates. Macromolecular Chemistry and Physics, 211, 627–634. DOI: 10.1002/macp.200900444. http://dx.doi.org/10.1002/macp.20090044410.1002/macp.200900444Search in Google Scholar
[6] Gospodinova, N., & Terlemezyan, L. (1998). Conducting polymers prepared by oxidative polymerization: polyaniline. Progress in Polymer Science, 23, 1443–1484. DOI: 10.1016/s0079-6700(98)00008-2. http://dx.doi.org/10.1016/S0079-6700(98)00008-210.1016/S0079-6700(98)00008-2Search in Google Scholar
[7] Heinson, W. R., Sorensen, C. M., & Chakrabarti, A. (2012). A three parameter description of the structure of diffusion limited cluster fractal aggregates. Journal of Colloid and Interface Science, 375, 65–69. DOI: 10.1016/j.jcis.2012.01.062. http://dx.doi.org/10.1016/j.jcis.2012.01.06210.1016/j.jcis.2012.01.062Search in Google Scholar PubMed
[8] Hoeben, F. J. M., Jonkheijm, P., Meijer, E. W., & Schenning, A. P. H. J. (2005). About supramolecular assemblies of π-conjugated systems. Chemical Reviews, 105, 1491–1546. DOI: 10.1021/cr030070z. http://dx.doi.org/10.1021/cr030070z10.1021/cr030070zSearch in Google Scholar PubMed
[9] Huang, Y. F., & Lin, C. W. (2009). Introduction of methanol in the formation of polyaniline nanotubes in an acid-free aqueous solutions through a self-curling process. Polymer, 50, 775–782. DOI: 10.1016/j.polymer2008.12.016. http://dx.doi.org/10.1016/j.polymer.2008.12.016Search in Google Scholar
[10] Inzelt, G., & Puskás, Z. (2004). Absorption and precipitation during the redox transformation of phenazine. Electrochimica Acta, 49, 1969–1980. DOI: 10.1016/j.electacta.2003.12.027. http://dx.doi.org/10.1016/j.electacta.2003.12.02710.1016/j.electacta.2003.12.027Search in Google Scholar
[11] Kellenberger, A., Dmitrieva, E., & Dunsch, L. (2011). The stabilization of charge states at phenazine-like units in polyaniline under p-doping: an in situ ATR-FTIR spectroelectrochemical study. Physical Chemistry Chemical Physics, 13, 3411–3420. DOI: 10.1039/c0cp01264e. http://dx.doi.org/10.1039/c0cp01264e10.1039/c0cp01264eSearch in Google Scholar PubMed
[12] Kim, J. Y., Kwon, M. H., Kim, J. T., Kwon, S. J., Ihm, D.W., & Min, Y. K. (2007). Crystallization growth and micropatterning of self-accembled conductive polymer nanofilms. The Journal of Physical Chemistry C, 111, 11252–11258. DOI: 10.1021/jp0683622. http://dx.doi.org/10.1021/jp068362210.1021/jp0683622Search in Google Scholar
[13] Křžá, M., & Stejskal, J. (2011). NMR investigation of aniline oligomers produced in the oxidation of aniline in alkaline medium. Polymer International, 60, 1296–1302. DOI: 10.1002/pi.3079. 10.1002/pi.3079Search in Google Scholar
[14] Laslau, C., Zujovic, Z., & Travas-Sejdic, J. (2010). Theories of polyaniline nanostructure self-assembly: Towards an expanded, comprehensive Multi-Layer Theory (MLT). Progress in Polymer Science, 35, 1403–1419. DOI: 10.1016/j.progpolymsci.2010.08.002. http://dx.doi.org/10.1016/j.progpolymsci.2010.08.00210.1016/j.progpolymsci.2010.08.002Search in Google Scholar
[15] Lee, Y.H., Chang, C. Z., Yau, S. L., Fan, L. J., Yang, Y. W., Ou Yang, L. Y., & Itaya, K. (2009). Conformations of polyaniline molecules adsorbed on Au(111) probed by in situ STM and ex situ XPS and NEXAFS. Journal of the American Chemical Society, 131, 6468–6474. DOI: 10.1021/ja809263y. http://dx.doi.org/10.1021/ja809263y10.1021/ja809263ySearch in Google Scholar
[16] Olad, A., Ilghami, F., & Nosrati, R. (2012). Surfactant-assisted synthesis of polyaniline nanofibres without shaking and stirring: effect of conditions on morphology and conductivity. Chemical Papers, 66, 757–764. DOI: 10.2478/s11696-012-0197-4. http://dx.doi.org/10.2478/s11696-012-0197-410.2478/s11696-012-0197-4Search in Google Scholar
[17] Ou Yang, L. Y., Chang, C. Z., Liu, S. H., Wu, C. G., & Yau, S. L. (2007). Direct visualization of an aniline admolecule and its electropolymerization on Au(111) with in situ scanning tunneling microscope. Journal of the American Chemical Society, 129, 8076–8077. DOI: 10.1021/ja072201+. http://dx.doi.org/10.1021/ja072201+10.1021/ja072201+Search in Google Scholar
[18] Puskás, Z., & Inzelt, G. (2005). Formation and redox transformations of polyphenazine. Electrochemica Acta, 50, 1481–1490. DOI: 10.1016/j.electacta.2004.10.021. http://dx.doi.org/10.1016/j.electacta.2004.10.02110.1016/j.electacta.2004.10.021Search in Google Scholar
[19] Sapurina, I., Riede, A., & Stejskal, J. (2001). In-situ polymerized polyaniline films: 3. Film formation. Synthetic Metals, 123, 503–507. DOI: 10.1016/s0379-6779(01)00349-6. http://dx.doi.org/10.1016/S0379-6779(01)00349-610.1016/S0379-6779(01)00349-6Search in Google Scholar
[20] Sapurina, I., & Stejskal, J. (2008). The mechanism of the oxidative polymerization of aniline and the formation of supramolecular polyaniline structures. Polymer International, 57, 1295–1325. DOI: 10.1002/pi.2476. http://dx.doi.org/10.1002/pi.247610.1002/pi.2476Search in Google Scholar
[21] Sapurina, I. Yu., & Stejskal, J. (2010). The effect of pH on the oxidative polymerization of aniline and the morphology and properties of products. Russian Chemical Reviews, 79, 1123–1143. DOI: 10.1070/rc2010v079n12abeh004140. http://dx.doi.org/10.1070/RC2010v079n12ABEH00414010.1070/RC2010v079n12ABEH004140Search in Google Scholar
[22] Sapurina, I. Yu., & Stejskal, J. (2012). Oxidation of aniline with strong and weak oxidants. Russian Journal of General Chemistry, 82, 256–275. DOI: 10.1134/s1070363212020168. http://dx.doi.org/10.1134/S107036321202016810.1134/S1070363212020168Search in Google Scholar
[23] Schnippering, M., Powell, H. V., Mackenzie, S. R., & Unwin, P. R. (2009). Real-time monitoring of polyaniline nanoparticles formation on surfaces. The Journal of Physical Chemistry C, 113, 20221–20227. DOI: 10.1021/jp906771c. http://dx.doi.org/10.1021/jp906771c10.1021/jp906771cSearch in Google Scholar
[24] Skotheim, T. A., & Reynolds, J. R. (Eds.) (2007). Conjugated polymers: Theory, synthesis, properties, and characterization (Handbook of conducting polymers). Boca Raton, FL, USA: CRC Press. Search in Google Scholar
[25] Stejskal, J., Sapurina, I., Prokeš, J., & Zemek, J. (1999). In-situ polymerized polyaniline films. Synthetic Metals, 105, 195–202. DOI: 10.1016/s0379-6779(99)00105-8. http://dx.doi.org/10.1016/S0379-6779(99)00105-810.1016/S0379-6779(99)00105-8Search in Google Scholar
[26] Stejskal, J., Trchová, M., Fedorova, S., Sapurina, I., & Zemek, J. (2003). Surface polymerization of aniline on silica gel. Langmuir, 19, 3013–3018. DOI: 10.1021/la026672f. http://dx.doi.org/10.1021/la026672f10.1021/la026672fSearch in Google Scholar
[27] Stejskal, J., Sapurina, I., & Trchová, M. (2010). Polyaniline nanostructures and the role of aniline oligomers in their formation. Progress in Polymer Science, 35, 1420–1481. DOI: 10.1016/j.progpolymsci.2010.07.006. http://dx.doi.org/10.1016/j.progpolymsci.2010.07.00610.1016/j.progpolymsci.2010.07.006Search in Google Scholar
[28] Tran, H. D., Li, D., & Kaner, R. B. (2009). One-dimensional conducting polymer nanostructures: Bulk synthesis and applications. Advanced Materials, 21, 1487–1499. DOI: 10.1002/adma.200802289. http://dx.doi.org/10.1002/adma.20080228910.1002/adma.200802289Search in Google Scholar
[29] Trchová, M., Morávková, Z., Šeděnková, I., & Stejskal, J. (2012). Spectroscopy of thin polyaniline films deposited during chemical oxidation of aniline. Chemical Papers, 66, 415–445. DOI: 10.2478/s11696-012-0142-6. http://dx.doi.org/10.2478/s11696-012-0142-610.2478/s11696-012-0142-6Search in Google Scholar
[30] Tzou, K., & Gregory, R. V. (1992). Kinetic study of the chemical polymerization of aniline in aqueous solutions. Synthetic Metals, 47, 267–277. DOI: 10.1016/0379-6779(92)90367-r. http://dx.doi.org/10.1016/0379-6779(92)90367-R10.1016/0379-6779(92)90367-RSearch in Google Scholar
[31] Wozniak, M., Onofri, F. R. A., Barbosa, S., Yon, J., & Mroczka, J. (2012). Comparison of methods to derive morphological parameters of multi-fractal samples of particle aggregates from TEM images. Journal of Aerosol Science, 47, 12–26. DOI: 10.1016/j.jaerosci.2011.12.008. http://dx.doi.org/10.1016/j.jaerosci.2011.12.00810.1016/j.jaerosci.2011.12.008Search in Google Scholar
[32] Yau, S. L., Lee, Y. H., Chang, C. Z., Fan, L. J., Yang, Y. W., & Dow, W. P. (2009). Structures of aniline and polyaniline molecules adsorbed on Au(111) electrode: as probed by in situ STM, ex situ XPS, and NEXAFS. The Journal of Physical Chemistry C, 113, 13758–13764. DOI: 10.1021/jp9027194. http://dx.doi.org/10.1021/jp902719410.1021/jp9027194Search in Google Scholar
© 2012 Institute of Chemistry, Slovak Academy of Sciences
