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The oxidative polymerization of 3,6-phenylenediamino-2,5-dichlorobenzoquinone is studied for the first time, and the monomer is shown to exhibit a high reactivity in this process. The rate of its polymerization is much higher than that of aniline and 3,6-dianiline-2,5-dichlorobenzoquinone, and the induction period of oxidation is absent. The kinetic features of the oxidative polymerization of 3,6-phenylenediamino-2,5-dichlorobenzoquinone are investigated by measuring variation in the redox potential of the reaction mixture in the course of time. It is found that the kinetic curves of 3,6-phenylenediamino-2,5-dichlorobenzoquinone polymerization do not follow the S-shaped pattern typical of aniline polymerization. The mechanism of polymerization proceeding through a number of successive tautomeric rearrangements is advanced. The structure of the polymers is studied by FTIR and X-ray photoelectron spectroscopy. During the reaction of oxidative polymerization, cyclization processes occur to form phenazine and phenoxazine rings which give rise to a ladder polyconjugated polymer. The effect of reaction conditions, such as the concentration of reagents, their ratio, and the pH of the reaction medium, on the process is investigated.

Hybrid nanocomposites based on poly(3,6-di(3-aminophenyl)amino-2,5-dichloro-1,4-benzoquinone) and single-walled carbon nanotubes were obtained under monomer polymerization conditions in concentrated formic acid under the action of benzoyl peroxide in the presence of single-walled carbon nanotubes. The electrochemical behavior in an aprotic lithium electrolyte of composite electrodes having the form of strips of anodized graphite foil having on its surface an active layer of a stable suspension of the nanocomposite in formic acid was examined in the absence of any binding and electrically conducting additives. The specific electrochemical capacitance of the coating reaches a value of 500 F g−1 at a charge-discharge current of 1.5 mA cm−2 in an inorganic electrolyte composed of 1 M LiClO4 in propylene carbonate. It was found that the Faraday pseudo-capacitance makes an insignificant contribution to the electrochemical capacitance of composite electrodes, which is mostly determined by the charging of an electric double layer. The nanocomposite coatings are characterized by high stability of their electrochemical characteristics at a coulomb efficiency of 97–100%. The fall of the capacitance upon prolonged cycling (>300 cycles) does not exceed 4%. The electrochemical characteristics of electrodes on friable substrates of anodized graphite foil strongly surpass those for electrodes obtained on nickel or rolled graphite foil as substrates.

The oxidative polymerization of 3,6-dianiline-2,5-dichlorobenzoquinone is studied for the first time and it is shown that its reactivity in oxidation processes is higher than that of aniline. The influence of concentration, reagent ratio, and the acidity and temperature of reaction solution on the oxidation reaction is investigated. The specific features of polymerization of 3,6-dianiline-2,5-dichlorobenzoquinone determined by the presence of a chloranil substituent at the nitrogen atom are revealed. Poly(3,6-dianiline-2,5-dichlorobenzoquinone) has a highly ordered supramolecular structure. The copolymerization of 3,6-dianiline-2,5-dichlorobenzoquinone with aniline is studied, and it is found that the reaction kinetics and the degree of copolymer oxidation are determined by aniline content in the monomer mixture.

New oxidative polymerization monomers—diarylaminodichlorobenzoquinones were synthesised by alkylating aniline, m-phenylenediamine and methanilic acid with chloranil. Oxidative polymerization of diarylaminodichlorobenzoquinones was studied for the first time in relation to the concentration of the monomer, acid, and oxidant/monomer ratio. It was found that the synthesized monomers are highly active in the polymerization reaction, and the oxidation rate grows with the increase in the acid concentration. Only one arylamine group is involved in the polymerization reaction. The optimal oxidant/monomer ratio is stoichiometric for one arylamine group, despite the bifunctionality of the monomers. It was shown that the type of the substituent in the aniline ring (electron donor or electron acceptor) determines the growth of the polymer chain and the structure of the resulting conjugated polymers. A mechanism for the formation of active polymerization centers for diarylaminodichlorobenzoquinones was proposed. FTIR-, NMR-, X-ray photoelectron spectroscopy, and SEM were used to identify the structure of the synthesized monomers and polymers. The obtained polymers have an amorphous structure and a loose globular morphology. The frequency dependence of the electrical conductivity was studied.

The method of synthesizing nanocomposites based on multiwalled carbon nanotubes and a new polymer poly(3,6-bis(phenylamino)-2,5-dichlorobenzoquinone) containing polyaniline chains with electroactive substituents in the N-position is developed, and the electrochemical properties of the composites are studied. The in situ oxidative polymerization of N-substituted aniline performed in the presence of multiwalled carbon nanotubes makes it possible to design an organized, effective structure of the conducting composite material with enhanced electrochemical capacity and stable capacity parameters during long cycling in protic (1 mol/L H2SO4) and aprotic (1 mol/L LiClO4 in propylene carbonate) electrolytes.

A procedure has been developed for electrochemical polymerization of dianiline dichlorobenzoquinone and electrosynthesis of a composite material based on poly(dianiline dichlorobenzoquinone) and multiwalled carbon nanotubes (MCNTs) in 1 M H2SO4. The introduction of a polymerization initiator (potassium hexachloroiridate IrCl62− (HCI)) accelerated the growth of the electrode coating. The introduction of MCNTs led to the creation of a current-conducting framework in the composite and an increase in the mass and electrochemical capacity of the electrode coating. The electrochemical behavior of the composite is similar to that of polyaniline (PAni), but includes the redox reaction of the chloranil substituents. The charging of the double electric layer makes a significant contribution to the electrochemical capacity.

The effect of substituted aromatic amines on the process of heterophase oxidative polymerization of aniline and the quality of the formed polyaniline layers was studied for regulation of characteristics of composites based on them. It was shown that p-phenylenediamine (p-PDA), being a catalyst of the oxidation process at the start of the reaction produces practically no effect on the rate of polyaniline formation at the interface. M-phenylenediamine (m-PDA) shows strong inhibitory properties by increasing the induction period of the reaction and decreasing the rate of the reaction. Diphenylamine (DPA) produces practically no effect on the kinetic parameters of the process, but it impairs the quality of the forming polyaniline layers. Composite films, formed on the basis of polystyrene solution and polyaniline microlayers, obtained directly during the reaction, 58are characterized by homogeneity and excellent electrophysical and strength properties.

Approaches for the development of anisotropic electroconducting composite materials based on polyaniline and Na-montmorillonite prepared by the me thods of boundary and intercalation polymerization of aniline and mechanical blending are proposed. Parallel plane compression of solid and plasticized dispersions is shown to lead to the development of primarily planar ordering of anisometric clay particles with sorbed or intercalated polymer; as a result, nanocomposites with anisotropic electrical conductivity are formed. In the prepared polymer-silicate films, the parameter of anisotropy in electrical conductivity achieves 6 × 103.

The oxidative polymerization of aniline has been studied under heterophase conditions on the surface of solid and liquid substrates. It has been shown that the kinetic features and the structure of the products of heterophase synthesis differ appreciably from the corresponding characteristics of the process occurring in the bulk of the reaction solution. Formation of the polyaniline layer at the interface may be attributed to two independent reactions, namely, borderline and adsorption polymerizations. Only the first process is responsible for formation the ordered polymer coating. In the context of the electrical double layer model, the mechanism of the borderline polymerization best corresponds to the experimental data.

The chemical oxidative polymerization of aniline in a heterophase system is studied. In the presence of a solid substrate, the aniline polymerization involves two kinetically and chemically independent processes, namely, the polymerization in the bulk solution and at the substrate surface. The growth of the polyaniline coating at the substrate surface includes three successive processes: interfacial polymerization, adsorptive polymerization, and destruction of the polymer chain. The interfacial oxidative polymerization of diphenylamine and phenothiazine is examined. The yield and chemical structure of polymers is shown to depend on the polymerization conditions.

A cholinesterase potentiometric sensor based on a glassy carbon electrode modified with processible polyaniline has been developed and explored for the detection of organophosphorus and carbamic pesticides. Acetyl- and butyryl-cholinesterase from various sources were immobilized on the surface of a polyaniline modified electrode by cross-linking with glutaraldehyde. Polyaniline modification made it possible to obtain a reversible pH response of about 86-mV/pH unit and to improve the analytical and operational characteristics of substrate and inhibitor detection. The sensitivity of pesticide detection depends on both the source of the enzyme and its activity and on pesticide hydrophobicity. The detection limits of the pesticides investigated (Trichlorfon, 1.5/spl middot/10/sup -7/ mol/l, Coumaphos, 5/spl middot/10/sup -9/ mol/l, Methiocarb, 8/spl middot/10/sup -7/ mol/l, Aldicarb, 2/spl middot/10/sup -7/ mol/l) were found lower than those obtained with other similar cholinesterase sensors. The possibility for the detection of the trace amounts of pesticides in river waters and grape juice with cholinesterase sensors developed has been established on model samples.

Composite films based on the polyvinyltrimethylsilane (PVTMS) with polyaniline (PANI) coating were obtained by borderline polymerization of aniline. The obtained coating was shown to differ from the polymer forming in the reaction mixture bulk both in chemical structure and morphology. Ratio and concentration of the reagents, mixing rate, reaction time, and condition of support surface were among the investigated factors affecting the growth and quality of PANI coating. The gas separation characteristics of composite membranes, as affected by the process conditions and the type of PANI, were investigated. It is shown that the proposed method provides a means for obtaining composite membranes that combine high selectivity, especially in O2/N2, He/CH4, and CO2/CH4 separation, with permeability higher than that of known composite materials. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1379–1384, 2003

The electroactivity of chemically synthesized polyaniline and its copolymer with metanilic acid has been investigated in a wide pH range. It was found that the external doping of PAn with camphorsulfonic acid extends the electroactivity in neutral and alkaline media. Additional ring substitution with sulfo-groups does not further extend the electroactivity, but improves the stability upon cycling in neutral and alkaline media.

Cholinesterase sensors based on glassy carbon and planar epoxy graphite electrodes modified with processed polyaniline have been developed and examined for pesticide detection. The modification of electrode surface with polyaniline provides high operational stability and sensitivity towards the pesticides investigated. The detection limits found (coumaphos, 0.002, trichlorfon, 0.04, aldicarb, 0.03, methiocarb, 0.08 mg l(-1)) make it possible to detect the pollutants in the waters on the level of limited threshold levels without sample preconcentration.

The cross sections for ρ0,\(\bar K^{*0} (890)\),Δ+ +,Δ0 andφ0 are measured for the 6, 8 and 10 particle exclusive channels in aK−p experiment at 32 GeV/c. For the channelK−p→K−2π−2π+ this study is done separately for the diffractive and non-diffractive components, separated by a rapidity gap method. It was found that the proportion ofK−,p andK−,p and π±, coming from resonance decay is a decreasing function of the channel multiplicity.