Synthesis and Characterization of Novel Nanophase Hexagonal Poly(2,5‐dimethoxyaniline)

Abstract

Novel nanophase hexagonal structured polyaniline (PANI) and poly(2,5-dimethoxyanilines) (PDMA) were synthesized by oxidative polymerization involving the respective anilines and a mixture of ferric chloride and ammonium persulfate. The morphological, spectral and electrochemical characteristics of the polymers were determined from the results of SEM, FTIR, UV-vis, TGA and cyclic voltammetry experiments. The hexagonal PANI and PDMA nanorods (15 -200 nm diameter) exhibited very good thermal stabilities, losing only 10% of their weight on heating to 400 8C. Electrochemical data indicated a pernigraniline state of the polymers with formal potential, E8', values of 394 AE 6 mV and 400 AE 1 mV, for PANI (conductance, C ¼ 0.37 Â 10 À3 S) and PDMA (conductance, C ¼ 2.02 Â 10 À3 S), respectively. The pernigraniline state was confirmed by sharp FTIR pernigraniline quinoidic peaks (PANI: 1414 cm À1 ; PDMA: 1157 cm À1), and UV-vis absorption maxima at 340 -370 nm (PANI) and 450 -650 nm (PDMA) which are characteristic of charge transfer excitons of the quinoid structures of pernigraniline.

Mechanism of charge transport in poly(2,5-dimethoxyaniline)

“…4 The synthesis was carried out in acidic deionized water ͑DI͒. 2,5-dimethoxyaniline ͑DMA͒, FeCl 3 , and APS were purchased from Fluka, Sigma-Aldrich and Ranbaxy Laboratories, respectively, and used as such without any further purification.…”

“…To improve upon the processability of PANI, its substituted forms such as poly͑2-methoxyaniline͒, poly͑methy-laniline͒, and poly͑2,5-dimethoxyaniline͒ ͑PDMA͒ have been synthesized. [3][4][5] However, only PDMA has comparable conductivity to its PANI counterpart. 5 Prior to any device application, the study of charge generation, and its transport in this system are very important.…”

Synthesis of hollow poly(aniline-co-pyrrole)–Fe3O4 composite nanospheres and their microwave absorption behavior

“…4 (c-f)) at 1575, 1564, 1458, 1281, 1190 and 694 cm -1 . The bands at 1575 and 1564 cm -1 correspond to the C-C stretch for the quinonoid phenyl rings of PANI and C=C stretching mode of polypyrrole [8,22]. The peak at 1458 cm -1 is attributed to benzenoid vibrations, and the bands at 1281 and 1190 cm -1 are due to the presence of aromatic NH groups and the C-N stretching vibration [18,23].…”

Influence of Binary Oxidant (FeCl<sub>3</sub>:APS) Ratio on the Spectroscopic and Microscopic Properties of Poly(2,5-Dimethoxyaniline)

“…The one dimensional nano-structured conducting polymers are also of interest to researchers because of its applications in molecular, electronic and electrochromic display devices [7]. It has been shown [8][9][10] that the electronic transport of conducting polymers bears a strong correlation with its structural and morphological factors. Among the family of conducting polymers, polyaniline (PANI) is one of the most widely investigated materials [11].…”

“…One dimensional nano-structures of PANI is being synthesized by chemical oxidative or electrochemical polymerization of monomer with the help of surfactant acting as a template, [17] whereas PANI nanorods and nanotubes have been synthesized without using any surfactant [8,18]. Formation of a cluster of hexagonal nanorods of PANI is also reported in literature [10] by using binary oxidants during its synthesis. The advantages of nano-structured polymers are its better carrier transport and electrochemical activity.…”