Aniline chemical oxidative polymerization

Instead of chemical oxidative polymerization, electropolymerization can also be considered. A recent study shows that slow but efficient electropolymerization is possible if anilinium-exchanged zeolite Y is subjected to oxidative treatment at the electrode-electrolyte interface. Cyclic voltammetric signatures of the polymerization suggest that it occurs mostly through one dimer (p-aminodiphenylamine) which imdergoes oxidative polymerization. Electrochemical polymerization of aniline in zeolite molecular sieves was studied. A zeolite-modified electrode showed shape-selectivity for 12-molybdophosphoric acid. 

A. Yasuda and T. Shimidzu, Chemical oxidative polymerization of aniline with ferric chloride, Polym. J., 1993, 25, 329. 

Chemical Oxidative Polymerization of Aniline Hard (Physical) Template Methods... 

Nanoporous Hard-Template Methods PANI-NTs have been prepared by the chemical oxidative polymerization of aniline within the pores of PC nanoporous membranes... 

PANI nanoribbons, also known as nanobelts, have been synthesized by a self-assembly process using the chemical oxidative polymerization of aniline in a surfactant gel, formed by mixing an acetic acid solution of anihne and CTAB with an aqueous solution of APS... 

Composites of PANI-NFs, synthesized using a rapid mixing method, with amines have recently been presented as novel materials for phosgene detection [472]. Chemiresistor sensors with nanofibrous PANI films as a sensitive layer, prepared by chemical oxidative polymerization of aniline on Si substrates, which were surface-modified by amino-silane self-assembled monolayers, showed sensitivity to very low concentration (0.5 ppm) of ammonia gas [297]. Ultrafast sensor responses to ammonia gas of the dispersed PANI-CSA nanorods [303] and patterned PANI nanobowl monolayers containing Au nanoparticles [473] have recently been demonstrated. The gas response of the PANI-NTs to a series of chemical vapors such as ammonia, hydrazine, and triethylamine was studied [319,323]. The results indicated that the PANI-NTs show superior performance as chemical sensors. Electrospun isolated PANI-CSA nanofiber sensors of various aliphatic alcohol vapors have been proven to be comparable to or faster than those prepared from PANI-NF mats [474]. An electrochemical method for the detection of ultratrace amount of 2,4,6-trinitrotoluene with synthetic copolypeptide-doped PANI-NFs has recently been reported [475]. PANI-NFs, prepared through the in situ oxidative polymerization method, were used for the detection of aromatic organic compounds [476]. 

G. Ciric-Maijanovic, M. Trchova, and J. Stejskal, The chemical oxidative polymerization of aniline in water Raman spectroscopy, J. Raman Spectrosc., 39, 1375-1387 (2008). 

The synthesis of conjugated polymers is highly dependent on the effective carbon-carbon single bond generation between unsaturated carbons in aromatic molecules. Aromatic units in conjugated polymers can be benzene, aniline, pyrrole, thiophene, carbazole, naphthalenediimide, perylenediimide (PDI), or their derivatives, etc. Although monomers are various, their synthetic methods can be mainly classified into chemical and electrochemical polymerizations. Chemical polymerization includes chemical oxidative polymerization and metal-catalyzed coupling condensation. 

MnO has been also coated with PANl to improve its electrochemical performance. Shin et al found that the cobalt-intercalated layered manganese oxide (CLMO) displayed the excellent cyclability over 40 cycles, although it exhibited a low discharge capacity (143 mA h g at 40 mA g current density) [51]. After chemical oxidative polymerization of aniline... 

The in situ polymerization of aniline to form an electrically conductive textile was also first reported by Kuhn and coworkers [78,79] in which the polyaniline was deposited onto a textile substrate from an aqueous solution containing aniline, ammonium persulfate, hydrochloric acid, and either the disodium salt of 2,6-naphthalenedisulfonic acid or 1,3-benzenedisulfonic acid. In these studies, the polymerization conditions were controlled in order to deposit the polyaniline layer only onto the textile support with no polymer precipitating in the bulk liquid phase. This was accomplished by using dilute solutions of aniline (0.03 M). A subsequent study by Tzou and Gregory [92] on the deposition of polyaniline to nylon-6 fibers was focused on investigating the reaction kinetics of the chemically oxidative polymerization of aniline... 

In addition, one-phase smfactant-assisted chemical method has been utilized to synthesize PANI nanofiber, which was doped with CSA and 2-acrylamido-2-methyl-l-propanesulfonic acid, in large quantities [291]. A chemical oxidative polymerization of aniline has been carried out using ammonium peroxydisulfate as an oxidizing agent in the presence of nonionic surfactant. A precipitate of doped emeraldine salt is composed of PANI nanofiber, which has the diameter of 30-50 nm and exhibits the conductivity of 1 -5 S cm at RT. Another piece of research has been done through chemical oxidation polymerization of aniline in a surfactant gel, which was formed by a mixture of hexadecyltrimethylammonium chloride, acetic acid, anihne, and water at - 7 °C [292]. The dendritic PANI nanofiber has the diameter of 60-90 nm and the length of 1 -2 jim. Extended works have been performed by the electrospinning method [293]. It should be taken into account that PANI-CSA fiber shape could be influenced by the synthetic variables such as solvent, surface tension, viscosity, and solution conductivity. 

Polyaniline nanofibers are synthesized through a simple, non-templated method, based on a modification of the classic chemical oxidative polymerization of aniline that makes nanofibers of uniform diameters. These materials respond significantly better than conventional films. To make the polyaniline even better for sensor materials, the nanofibers are dispensed into water and are combined with metals salts into a composite material. These... 

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