Influence of Binary Oxidant (FeCl₃:APS) Ratio on the Spectroscopic and Microscopic Properties of Poly(2,5-Dimethoxyaniline)

Rajiv K. Singh, Amit Kumar, Khushboo Agarwal, Deepshikha Dwivedi, Keadar N. Sood, Ramadhar Singh

Department of Physics, Department of Kanya Gurukul, Gurukul Kangri University, Haridwar, India.
National Physical Laboratory, Council of Scientific & Industrial Research, New Delhi, India.

DOI: 10.4236/ojpchem.2012.23014                

Abstract

Poly(2,5-dimethoxyaniline) (PDMA) has been synthesized by chemical oxidative polymerization technique using varying ratio (wt/wt) of binary oxidants; ferric chloride (FeCl₃) and ammonium persulfate (APS). Fourier transform infrared (FT-IR) and ultraviolet-visible (Uv-vis) spectroscopic investigations provide the evidence of the presence of both benzenoid and quinoid ring units. The thermal analysis and structural characterization data suggests that the oxidant ratio greatly controls the molecular ordering in PDMA. Surface morphology shows the existence of both amorphous and crystalline domains wherein the crystalline domain size depends on the oxidant ratio. The dc conductivity (σdc) of PDMA is also a function of binary oxidant ratio and at FeCl₃:APS (50:50), it increases by two orders of magnitude. Films of PDMA synthesized using FeCl₃:APS (50:50) binary oxidant exhibits a decrease in the surface current on exposure to ammonia gas.

Keywords

Poly(2, 5-Dimethoxyaniline); Binary Oxidant; Structured Polymer; DC Conductivity

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	J. Y. Kim, K. Lee, N. E. Coates, D. Moses, T-Q. Nguyen, M. Dante and A. J. Heeger, “Efficient Tandem Polymer Solar Cells Fabricated by All-Solution Processing,” Science, Vol. 317, No. 5835, 2007, pp. 222-225. doi:10.1126/science.1141711
[2]	I. Kymissis, “Organic Field Effect Transistors: Theory, Fabrication and Characterization,” Springer Science, New York, 2009.
[3]	H. K. Song and G. R. Palmore, “Redox-Active Polypyrrole: Toward Polymer-Based Batteries,” Advance Materials, Vol. 18, No. 13, 2006, pp. 1764-1768. doi:10.1002/adma.200600375
[4]	A. A. Athawale, S. V. Bhagwat and P. P. Katre, “Nanocomposite of Pd-Polyaniline as a Selective Methanol Sensor,” Sensors Actuators B: Chemical, Vol. 114, No. 1, 2006, pp. 263-267. doi:10.1016/j.snb.2005.05.009
[5]	T.-K. Chang, C.-C. Chang and T.-C. Wen, “The Methanol Adsorption Behavior on Platinum/Poly(2,5-Dimethoxyaniline) Composites For Application In Methanol Sensing” Journal of Power Sources, Vol. 185, No. 2, 2008, pp. 603608. doi:10.1016/j.jpowsour.2008.09.033
[6]	M. Arulepp and L. Permann, “Influence of the Solvent Properties on the Characteristics of a Double Layer Capacitor,” Journal of Power Sources, Vol. 133, No. 2, 2004, pp. 320-328. doi:10.1016/j.jpowsour.2004.03.026
[7]	W. Lu, A. G. Fadeev, B. Qi and B. R. Mattes, “Fabricating Conducting Polymer Electrochromic Devices Using Ionic Liquids,” Journal of The Electrochemical Society, Vol. 151, No. 2, 2004, pp. H33-H39. doi:10.1149/1.1640635
[8]	Q. Sun, M. Park and Y. Deng, “Dendritic Superstructure Formation of Polyaniline Prepared Using a Water-Soluble Polyelectrolyte Copolymer as the Support Matrix,” Material Letters, Vol. 61, No. 14, 2007, pp. 3052-3055. doi:10.1016/j.matlet.2006.10.073
[9]	J. H. Hwang and S. C. Yang, “Morphological Modification of Polyaniline Using Polyelectrolyte Template Molecules,” Synthetic Metals, Vol. 29, No. 1, 1989, pp. 271276. doi:10.1016/0379-6779(89)90306-8
[10]	S. E. Mavundla, G. F. Malgas, P. Baker and E. I. Iwuoha, “Synthesis and Characterization of Novel Nanophase Hexagonal Poly(2,5-dimethoxyaniline),” Electroanalysis Vol. 20, No. 21, 2008, pp. 2347-2353. doi:10.1002/elan.200804326
[11]	D. W. Hatchett and M. Josowicz, “Composites of Intrinsically Conducting Polymers as Sensing Nanomaterials,” Chemical Reviews, Vol. 108, No. 2, 2008, pp. 746-769. doi:10.1021/cr068112h
[12]	P. Li, T. C. Tan and J. Y. Lee, “Corrosion Protection of Mild Steel by Electroactive Polyaniline Coatings,” Synthetic Metals, Vol. 88, No. 3, 1997, pp. 237-242. doi:10.1016/S0379-6779(97)03860-5
[13]	J. Huang and R. B. Kaner, “A General Chemical Route to Polyaniline Nanofibers,” Journal of the American Chemical Society, Vol. 126, No. 3, 2004, pp. 851-855. doi:10.1021/ja0371754
[14]	V. Bavastrello, E. Stura, S. Carrara, V. Erokhin and C. Nicolini, “Poly(2,5-Dimethylaniline)-MWNTS Nanocomposite: A New Material for Conductometric Acid Vapours Sensor,” Sensors and Actuators B: Chemical, Vol. 98, No. 2, 2004, pp. 247-253. doi:10.1016/j.snb.2003.10.020
[15]	P. Yin, P. A. Kilmartin, “Formation of Poly-2,5-Dimethoxyaniline on Steels,” Current Applied Physics, Vol. 4, No. 2, 2004, pp. 141-143. doi:10.1016/j.cap.2003.10.016
[16]	B. Palys, A. Kudelski, A. Stankiewicz and K. Jackowska, “Influence of Anions on Formation and Electroacitivity of Poly-2,5-Dimethoxyaniline,” Synthetic Metals, Vol. 108, No. 2, 2000, pp. 111-119. doi:10.1016/S0379-6779(99)00180-0
[17]	L. Yu, J. I. Lee, K. W. Shin, C. E. Park and R. Holze, “Preparation of Aqueous Polyaniline Dispersions by Micellar-Aided Polymerization,” Journal of Applied Polymer Science, Vol. 88, No. 6, 2003, pp. 1550-1555. doi:10.1002/app.12127
[18]	Z. Zhang, Z. Wei and M. Wan, “Nanostructures of Polyaniline Doped with Inorganic Acids,” Macromolecules, Vol. 35, No. 15, 2002, pp. 5937-5942. doi:10.1021/ma020199v
[19]	R. K. Singh, A. Kumar and R. Singh, “Mechanism of Charge Transport in Poly(2,5-Dimethoxyaniline)” Journal of Applied Physics, 2010, Vol. 107, No. 11, pp. 113711. doi:10.1063/1.3443564
[20]	D. C. Trivedi, “Handbook of Organic Conductive Molecules and Polymers,” Wiley, New York, 1997, pp. 505-572.
[21]	H. K. Chaudhari and D. S. Kelkar, “Investigation of Structure and Electrical Conductivity in Doped Polyaniline,” Polymer International, Vol. 42, No. 4, 1997, pp. 380-384. doi:10.1002/(SICI)1097-0126(199704)42:4<380::AID-PI727>3.0.CO;2-F
[22]	J. L. Camalet, J. C. Lacroix, S. Aeiyach and P. C. Lacaze, “Characterization of Polyaniline Films Electrodeposited on Mild Steel in Aqueous p-Toluenesulfonic Acid Solution,” Journal of Electroanalytical Chemistry, Vol. 445, No. 1, 1998, pp. 117-124. doi:10.1016/S0022-0728(97)00526-3
[23]	N. Kohut-Svelko, S. Reynaud and J. Francois, “Synthesis and Characterization of Polyaniline Prepared in the Presence of Nonionic Surfactants in An Aqueous Dispersion,” Synthetic Metals, Vol. 150, No. 2, 2005, pp. 107-114. doi:10.1016/j.synthmet.2004.12.022
[24]	J. M. Ginder and A. J. Epstein, “Role of Ring Torsion Angle in Polyaniline: Electronic Structure and Defect States,” Physics Review B, Vol. 41, No. 15, 1990, pp. 10674-10685. doi:10.1103/PhysRevB.41.10674
[25]	G. M. Neelgund, E. Hrehorova, M. Joyce and V. Bliznyuk, “Synthesis and Characterization of Polyaniline Derivative and Silver Nanoparticle Composites,” Polymer International, Vol. 57, No. 10, 2008, pp. 1083-1089. doi:10.1002/pi.2445
[26]	B. C. Roy, M. D. Gupta, L. Bhowmik and J. K. Ray, “Synthesis and Characterization of Poly(2,5-Dimethoxyaniline) and Poly(Aniline-co-2,5-dimethoxyaniline): The Processable Conducting Polymers,” Bulletin of Materials Science, Vol. 24, No. 4, 2001, pp. 389-396. doi:10.1007/BF02708636
[27]	R. Singh, J. Kumar, R. K. Singh, A. Kaur, R. D. P. Sinha, N. P. Gupta, “Low Frequency ac Conduction and Dielectric Relaxation Behavior of Solution Grown and Uniaxially Stretched Poly(Vinylidene Fluoride) Films,” Polymer, Vol. 47, No. 16, 2006, pp. 5919-5928. doi:10.1016/j.polymer.2006.06.023
[28]	B. Dong, B.-L. He, C.-L. Xu and H.-L. Li, “Preparation and Electrochemical Characterization of Polyaniline/MultiWalled Carbon Nanotubes Composites for Supercapacitor,” Material Science and Engineering B, Vol. 143, No. 1, 2007, pp. 7-13. doi:10.1016/j.mseb.2007.06.017
[29]	P. F. Van Hutten and G. Hadzioannou, “Handbook of Organic Conductive Molecules and Polymers,” Wiley, New York, 1997, pp. 1-86.
[30]	R. Singh, V. Arora, R. P. Tandon and S. Chandra, “Transport and Structural Properties of Polyaniline Doped With Monovalent and Multivalent Ions,” Polymer, Vol. 38, No. 19, 1997, pp. 4897-4902. doi:10.1016/S0032-3861(97)00013-X
[31]	S. Virji, J. X. Huang, R. B. Kaner and B. H Weiller, “Polyaniline Nanofiber Gas Sensors:? Examination of Response Mechanisms,” Nano Letters, Vol. 4, No. 3, 2004, pp. 491496. doi:10.1021/nl035122e
[32]	Q. Hao, X. Wang, L. Lu, X. Yang and V. M. Mirsky, “Electropolymerized Multilayer Conducting Polymers with Response to Gaseous Hydrogen Chloride,” Macromolecular Rapid Communications, Vol. 26, No. 13, 2005, pp. 1099-1103. doi:10.1002/marc.200500114
[33]	S. Virji, J. D. Fowler, C. O. Baker, J. X. Huang, R. B. Kaner and B. H. Weiller, “Polyaniline Nanofiber Composites With Metal Salts: Chemical Sensors for Hydrogen Sulfide,” Small, Vol. 1, No. 6, 2005, pp. 624-627. doi:10.1002/smll.200400155
[34]	K. Ogura, H. Shiigi, T. Oho and T. Tonosaki, “A CO2 Sensor with Polymer Composites Operating at Ordinary Temperature,” Journal of The Electrochemical Society, Vol. 147, No. 11, 2000, pp. 4351-4355. doi:10.1149/1.1394068
[35]	S. Virji, R. B. Kaner and B. H. Weiller, “Hydrogen Sensors Based on Conductivity Changes in Polyaniline Nanofibers,” Journal of Physical Chemistry B, Vol. 110, No. 44, 2006, pp. 22266-22270. doi:10.1021/jp063166g