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The aim of the paper is to develop a method of synthesising polyaniline (PANI) with excellent electrical conductivity.

The preparation of PANI was carried out by vibration of emulsifier (SDBS), oxidant (APS) and hydrochloric acid (HCl) solution concentration. The changes of temperature and time of reaction had also been observed and researched.

Changing of reaction conditions was found to have a great influence on polyaniline's conductivity. The optimum condition for preparing polyaniline salt is as follows: the molar ratio of n(An)/n(SDBS)/n(APS) is 10/10/9, the concentration of HCl is 0.9 M, stirred constantly at 0°C for a period of 3 h. By using this emulsion polymerisation pathway the maximum of conductivity of polyaniline is 4.35 s/cm.

The method can be widely applicable to coatings, preparation of exfoliated clay composites and solution blending with other commodity polymers.

The method could be adapted for use on an industrial scale.

The purpose of this paper is to study the inhibitive effect of p‐toluene sulfonic acid (p‐TSA) doped polyaniline on corrosion of copper in 0.1 M hydrochloric acid (HCl) solution.

The electrochemical deposition of polyaniline doped with p‐TSA on pure copper metal was studied potentiodynamically. The electrochemical study of the working electrode was performed at open‐circuit potential, then using potentiodynamic polarization and also with electrochemical impedance spectroscopy in 0.1 M HCl solution. The p‐TSA doped polymer deposit was characterized using Fourier transform infrared spectroscopy, with the UV‐vis and thermogravimetric analysis/differential scanning calorimetry techniques. The morphology of the deposited polymer was studied by scanning electron microscopy.

The results revealed that the p‐TSA self‐doped polymer had better corrosion inhibition efficiency than did the un‐doped polyaniline. It exhibited approximately 88.9 percent inhibition efficiency at 2x10⁻³ M concentration of p‐TSA, according to charge transfer resistance (R_ct) values evaluated from Nyquist plots.

The high dissolution tendency of metal surfaces generally occurs before the electropolymerization potential of the monomer is achieved. It was difficult to electrodeposit the conducting organic polymer on the surface of metal.

Some organic conducting polymers are toxic and hazardous from the environmental viewpoint. The electrochemical deposition of p‐TSA doped polyaniline is impractical for larger structures.

The paper demonstrates that p‐TSA doped polyaniline is environmentally benign and can be used for the protection of copper metal as a cathodic inhibitor.

The purpose of this paper is to study to minimize the self‐corrosion rate of Type 57S aluminium containing (97.7 per cent Al, 2 per cent Mn and 0.03 per cent Mg) in 2 M NaOH solution containing 0.2 M zinc oxide and 700 ppm of polyaniline.

The approach is used to measure weight loss and polarization measurements.

Results obtained show that as the amount of polyaniline is increased, the self‐corrosion rate of Alloy 57S aluminium decreases appreciably. Additionally, the open circuit potential is more in the case of 700 ppm level of polyaniline (−1.630 V) compare to 600 ppm level of polyaniline (−1.587 V). From this paper, it is also observed that the anodic polarization is greater than the cathodic polarization, thereby indicating that the overall corrosion of Alloy 57S 2 M NaOH containing 0.2 M ZnO and 700 ppm of polyaniline is under anodic control.

The results of the study clearly reveal that the overall corrosion of Alloy 57S aluminium in 2 M NaOH containing 0.2 M ZnO and 700 ppm of polyaniline is under anodic control. Hence, the 57S grade aluminium can be used as a potential candidate (anode) in alkaline batteries.

The purpose of this paper is to study the sensitivity and selectivity properties of polyaniline/tantalum pentoxide (PANI/Ta₂O₅) composite to liquid petroleum gas (LPG).

Polyaniline/tantalum pentaoxide (PANI/Ta₂O₅) composites were synthesized by in situ chemical polymerization method using ammonium persulphate as an oxidizing agent. This is the novel polymerization process for the direct synthesis of emeraldine salt phase of the polymer. The composites were characterized by FTIR, XRD and SEM. Temperature dependence conductivity of the composites shows thermally activated behaviour. Sensitivity and selectivity of the composites are studied.

The PANI/ Ta₂O₅ composites of 20 wt% and 30 wt% are showing maximum change in resistance against time when compared to pure PANI and other polyaniline composites when exposed to LPG. The 20 wt % composites show maximum sensitivity of 83% to LPG. The selectivity studies reveals that LPG could be sensed better when compared to oxyacetylene and other test gases.

Selectivity studies have been carried out and the sensor proved to be better than metal oxides sensors.

The sensing material is of low cost.

To the best of the authors' knowledge, studies on Ta₂O₅‐based gas sensor have not been reported previously.

The purpose of this investigation was to synthesize a doped polyaniline‐containing coating and investigate the anti‐corrosion properties of the coating on Mg‐Li alloy.

The doped polyaniline pigments were prepared by two different methods using ammonium persulphate as oxidant and hydrochloric acid, phosphoric acid, p‐toluene sulfonic acid and sulfosalicylic acid as doping agents. The doped polyaniline was characterized by Fourier transform infrared (FT‐IR) analysis, X‐ray diffraction (XRD) and scanning electron microscopy (SEM). The coatings consisted of polyaniline, epoxy resin and other additives that were formed on Mg‐Li alloy. The anti‐corrosion properties of the polyaniline‐containing coating on the Mg‐Li alloy were investigated in 3.5 wt.% NaCl solution using open circuit potential logging and electrochemical impedance spectroscopy.

The results of the electrochemical tests indicated that the polyaniline‐containing coatings showed better anti‐corrosion properties, as compared to conventional epoxy coatings on Mg‐Li alloy when exposed in 3.5 wt.% NaCl solution. The coating containing 2 wt.% polyaniline (relative to the mass of epoxy resin) doped with hydrochloric acid had the best anti‐corrosion properties on the Mg‐Li alloy.

Previous reports on the anti‐corrosion properties of polyaniline‐containing coatings focused mainly on the surface of iron, steel, aluminum and magnesium, and there have been few studies on the anti‐corrosion properties as protective coatings for Mg‐Li alloy.

A new electrochemical analysis based on ß-cyclodextrin (ß-CD) was developed for penicillin V (Peni-V) using polyaniline as a conducting polymer.

The preparation of modified electrode involves the incorporation of β-CD with membrane of polyaniline. Polyaniline, incorporating β-CD, was prepared by electrochemical polymerization method in a medium of hypochloride. Cyclic voltammetry and electrochemical impedance have been used to characterize this sensor. The detection and the kinetic study of modified platinum electrode are evaluated.

Results clearly indicate that β-CDs interfere with the polymerization mechanism with an inhibition factor. The inclusion phenomenon of β-CDs has been studied and applied to detect Peni-V. The principle of this electrochemical sensor is based on the chemical properties of β-CD, which were studied using the cyclic voltammetric method and impedance spectroscopy. The electrochemical behavior of Peni-V at concentrations between 10^–8 and 10^–2 M was measured versus Ag/AgCl at pH 7.4 and 30°C in a phosphate alkaline buffer. Relationship of Peni-V concentration in logarithmic mathematical form with current in potentiometric method and with resistance in impedimetric method were obtained.

The present study showed that the Pt electrode modified with Polyaniline–β-CD was an excellent candidate for sensitive penicillin analysis. The proposed electroanalytical technique is rapid, simple and inexpensive.

The purpose of this paper is to evaluate the inhibitive effect of a polyaniline copolymer, namely, poly(aniline‐co‐o‐anthranilic acid) solution, on the corrosion of carbon steel in hydrochloric acid. The effect of the different concentrations of the corrosion inhibitor also was investigated.

Fourier transform infrared spectroscopy was used to characterise the polyaniline copolymer. Weight loss measurements, potentiodynamic polarization and electrochemical impedance spectroscopy were carried out to determine the corrosion inhibition efficiency. Scanning electron microscopy was used to observe the morphology of the corroded surface.

The results indicated that polyaniline copolymer solution acts as an effective corrosion inhibitor for carbon steel in hydrochloric acid solution and that the adsorption of the compound on the metal surface obeys the Langmuir adsorption isotherm.

The corrosion inhibitor could have wide applications in the acid washing industry to reduce the corrosion rate of carbon steel in hydrochloric acid.

This paper reveals a new type of corrosion inhibitor prepared from a polyaniline copolymer.

The purpose of this study is to introduce mechanochemically prepared polyaniline anticorrosive additives. In primer coating technology, there is an increasing interest in the development of efficient anticorrosive additives which replace the conventional inorganic anticorrosive pigments like heavy metal chromates and phosphates normally added to primer paints for the coating on metals. Conducting polymers are found to be better alternatives.

Polyaniline phosphate is synthesized through solid-state conditions without using any solvent. The synthesized polyaniline phosphate is added in the primer formulation instead of zinc phosphate. Primers with different quantity of zinc phosphate are also formulated and studied for comparison. The comparison between their abilities to control corrosion of carbon steel were done with application of open-circuit potential monitoring, polarization and electrochemical impedance spectroscopy methods in 3.5 per cent NaCl solution.

Corrosion studies indicate that polyaniline phosphate can improve corrosion protection properties by taking part the passivation processes. The performance of polyaniline phosphate is better than zinc phosphate.

I certify that the results are from our original research and this paper is neither considered for publication elsewhere nor published previously.

Poly(styrenesulphonic acid)‐doped polyaniline has been synthesised and the influence of this polymeric compound on the inhibition of corrosion of mild steel in 1M HCl has been investigated using weight loss measurements, galvanostatic polarisation studies, electropermeation studies and a.c. impedance measurements. The polymer acts predominantly as an anodic inhibitor. Hydrogen permeation studies and a.c. impedance measurements clearly indicate a very effective performance of the compound as a corrosion inhibitor. The adsorption of the compound on the mild steel surface obeys Temkin's adsorption isotherm.

The purpose of this paper is to develop feasible composite electrodes with a long cycle life and large specific capacitance and to investigate optimal ratio between aniline and activated carbon materials.

PANI/AC composite electrode materials were synthesised by in situ polymerisation of aniline on activated carbon with ammonium persulphate as oxidant. Hybrid supercapacitors are assembled by putting Ni‐MH battery separator between positive and negative electrodes. The electrochemical performances of PANI/AC composite electrode materials and supercapacitors are studied.

The results show that the optimal ratio between aniline and activated carbon is 1:1.08. The specific capacitance of polyaniline electrode materials is 956 F g⁻¹. The specific capacitance of supercapacitors is 159.37 F g⁻¹. This result could be attributed to the pseudocapacitive effect of Ni(OH)₂. What's more, the activated carbon addition reduced the resistance of polymer electrode materials thus improving the cyclic life.

The supercapacitors can be used in the field of automobiles and can solve the problems of energy shortage and environmental pollutions.

A hybrid supercapacitor, which was immersed in alkaline solution, was assembled by putting Ni‐MH battery separator between two electrodes Ni(OH)₂ as positive electrode and polyaniline composites as negative electrode. In the case of alkaline solution, the capacitive performance of hybrid supercapacitor was improved and excellent.