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This paper describes new experimental evidence of the electropolymerization of furfural on non‐noble metals such as low‐carbon steel. The organic compound (2‐furancarboxaldehyde) was selected because it is easily obtained from biomass and other sources. These results confirm the possibility of synthesizing a polymeric film, with good adherence and stability that provides a new protective barrier against corrosion to this kind of metal.

Electrochemical methods such as chronoamperometry, chronopotentiometry and cyclic voltammetry (CV) were used to synthesize and characterize the polymer formed on the electrode surface. Some electrochemical impedance experiments were conducted in order to confirm the electrochemical behavior modification of the electrode, due to the presence of the organic film on the surface.

The polymer film could be grown galvanostatically, potentiostatically or, during CV. The corrosion protection afforded by polyfurfural (PFy) that had been formed on a low‐carbon steel surface was confirmed by the CV, EIS and polarization curves.

The possible synthesis of a new polymeric structure on a non‐noble metal is interesting from a practical point of view. However, more experiments are necessary in order to test other organic solvents and other non‐noble metals such as zinc, aluminium, copper, etc.

The corrosion protection afforded by PFy that had been formed on a low‐carbon steel surface was confirmed by the CV, EIS and polarization curves. Anodic current values associated with metal oxidation decreased when the metal surface was covered with the organic film.

This is the first paper that deals with the electropolymerization of furfural on this type of metal. It was not found in the literature evidences that this polymer was synthesized before.

The purpose of this paper is to develop modified composite materials that show improved mechanical and structural integrity.

To accomplish this goal, a novel functionalisation method of the carbon fibres (CFs) for the reinforcement of the composites surface was investigated. Through the electrografting of methacrylic acid (MAA) onto the surface of the CF, this treatment aims to selectively modify the surface of the carbon fabrics, in order to create active groups that can chemically react with the epoxy resin, under heat and pressure. By this way, better adhesion as mechanical interlocking between the resin and the reinforcement can be achieved.

The surface treatment was examined qualitatively by means of infrared spectroscopy, scanning electron microscopy and Raman spectroscopy. The CF reinforced polymers were manufactured via the hot-press technique and they were subsequently submitted to flexural, shear and nanoindentation test. Finally, the internal structural integrity was tested through micro-computing tomography.

Through this investigation, it will be determined if the electropolymerisation of MAA onto the CF surface enhances the mechanical and structural integrity of composite materials.

This paper aims to compare the inhibitive effects of polyaniline (PAni), poly(p-toluidine) and poly(aniline-co-p-toluidine) in hydrochloric acid (HCl) solution.

The electrochemical deposition of PAni, poly(p-toluidine) and poly(aniline-co-p-toluidine) on pure copper metal was studied potentiodynamically. The copolymer deposited was characterized by Fourier transform infrared (FTIR) spectroscopy, ultraviolet (UV)-visible spectroscopy and scanning electron microscopy (SEM). The corrosion inhibition studies on copper electrode were performed using electrochemical methods, viz, open circuit potential (OCP) measurements, potentiodynamic polarization scans and electrochemical impedance spectroscopy (EIS) tests, conducted in 0.1 M HCl solution.

The results of the study reveal that the copolymer of poly(aniline-co-p-toluidine) at the optimum concentration of 1 × 10−3 M has better corrosion inhibition efficiency as compared to PAni and poly(p-toluidine).

The conducting polymers are difficult to deposit on the metal surface because of their high dissolution tendency before the electropolymerization potential of the monomer is achieved.

From an environmental viewpoint, poly(aniline-co-p-toluidine) is a toxic and hazardous conducting polymer.

The paper demonstrates that poly(aniline-co-p-toluidine) showed better dispersion in different organic solvents and had higher corrosion inhibition efficiency than PAni.

The purpose of this paper is to synthesise the block copolymer of pyrrole (Py) with bis(4‐inobutyl)polydimethylsiloxane (DA.PDMS) by electrochemical method. The characterisation of the insoluble block copolymers, P(Py‐b‐DA.PDMS), was performed by cyclovoltammetric measurements, solid‐state conductivity and DSC measurements. The surface morphology of the copolymers was examined with scanning electron microscope (SEM).

Electropolymerisation process was performed potentiostatically and potentiodynamically. Redox behaviour of the resulting copolymer films was investigated. In‐situ spectroelectrochemical measurement was carried out on indium thin oxide (ITO) electrodes.

The ionisation potentials (Ip), electron affinity (Ea), optical band gap (Eg), peak potentials (Ep), and doping degree (y) of copolymers were calculated by using in‐situ spectroelectrochemical measurement results. The copolymers have slightly lower doping degree, band gap, Ip and Ea values than homopolymer. Copolymers had the conductivities of 10‐5 S/cm and had Tg values.

This study can also be focused on obtaining conductive copolymer with insulator DA.PDMS blocks on the PPy chain by one‐step polymerisation.

This work provides technical information for the synthesis and characterisation of conducting block copolymer by electrochemical method.

Change in optical and electrical properties of the P(Py‐b‐DA.PDMS) shows the role of the individual properties of the copolymer blocks. While the DSC scan of PPy showed no transition temperature, which is a characteristic property of conducting copolymers, P(Py‐b‐DA.PDMS) had Tg values. This might be due to the inclusion of the DA.PDMS blocks on the PPy chains.

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.

This paper aims to investigate the protection efficiency of a thin film of electrochemically synthesized conducting polymers, such as poly m‐toluidine, poly N‐methyl aniline, and its copolymer, poly (aniline‐co‐N‐methyl aniline) (PANINMA), on plain carbon steel in 0.1 M HCl. It also attempts to compare the protection efficiency of these compounds with polyaniline (PANI)‐coated carbon steel.

The green coloured and adherent coatings were obtained by cyclic voltammetry during sequential scanning of the potential region between −0.6 and 1.6 V at a scan rate of 10 mVs⁻¹. Potentiodynamic polarization measurement (DC) was used to obtain an estimate of the corrosion rate and protection efficiency for these electrodeposited polymers on the carbon steel. Scanning electron micrographs (SEM) also were obtained to characterize the deposited coatings.

It was observed that these polymer coatings showed better protection efficiency than the PANI coating. Of the compounds studied, the copolymer PANINMA coating showed higher protection efficiency than other coatings. The SEM observations revealed that the compact continuous dense morphology of PANINMA provided better protection than other coatings.

This paper explains the protection efficiency of the substituted and copolymer coatings of PANI on carbon steel.

The purpose of this paper was to investigate the anti-corrosion behavior of polypyrrole (PPy) films in different states and presence of alumina nanoparticles synthesized by galvanostatic electropolymerization on stainless steel (SS) electrodes in an artificial seawater solution using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS).

The electrochemical measurements were used to examine the effects of PPy and its nanocomposite on the corrosion behavior of SS type 316L in artificial seawater. A standard electrochemical cell with three electrodes was used for the measurements. The electrochemical response of the coated electrodes in the doped and the undoped state was compared with that of a bare electrode. Corrosion rate information was obtained by the Tafel extrapolation method, where the intersection point of a cathodic and an anodic polarization curve provides both the corrosion potential and the corrosion current. EIS measurements confirmed the potentiodynamic and open circuit potential (OCP) results. The microstructure of the obtained films was investigated by scanning electron microscopy.

The results showed that the coated polymer films shifted the electrode potential toward more positive potentials, but this shift did not lead to passivation. However, a notable synergy was observed between PPy undoped film, oxygen reduction and iron dissolution. The potential of the SS remained in the active dissolution region, and it was not possible to produce a passive oxide layer in this region. PPy separates the metal dissolution process from the oxygen reduction process. This would prevent the local pH increase at the metal surface and subsequent delamination. The polarization curves, EOCP and impedance measurements showed that PPy undoped/Al₂O₃ layers show promise as good candidates for the corrosion protection of reactive metals.

This paper presents that electrodes coated with undoped PPy synthesized in the presence of dodecyl sulfate anions and Al₂O₃ nanoparticles offered a noticeable enhancement of protection against corrosion processes.

The purpose of this paper is to produce non-conductive copolymers of N-vinyl carbazole (NVCz) and methyl ethyl ketone formaldehyde resin (MEKFR) by the electroinduced Ce (IV) polymerization method and the electrochemical oxidization of the formed copolymer to produce their conductive green form. The non-conductive and conductive copolymers were characterized by using Fourier transform infrared, solid-state conductivity and spectroelectrochemical, chronoamperometric, cyclovoltammetric and electrochemical impedance spectroscopic measurements.

The chronoamperometric electropolymerization of white, insulator form of the copolymer of NVCz and MEKFR (copolymer 1) on to Pt electrode was carried out and the green coloured film of the MEKFR-ox-NVCz copolymer (copolymer 11) was produced in the doped and conductive form. All reactions were performed in dichloromethane containing 0.1 M B_U4NClO₄. Copolymer 11 films obtained on the surface of the working electrode were removed and washed in acetonitrile and dried at room temperature before characterization. The results were compared with the copolymer obtained by electrochemical oxidation of MEKF-R and NVCz (copolymer 2).

The insulating copolymer of NVCz and MEKFR (copolymer 1) was produced by the electroinduced Ce (IV) polymerization method and converted into the conductive form electrochemically on the surface of the Pt electrode (copolymer 11). The polymers were characterized by electrochemical, spectrophotometric and conductivity measurements. The ionization potentials, optical band gap, peak potentials Ep, doping degree and specific capacitance of the copolymer 11 were obtained. The conductivity of the copolymer 11 is lower than the PNVCz and higher than the copolymer obtained by electrochemical oxidation of MEKF-R and NVCz (copolymer 2). The copolymer 11 has a lower onset potential than PNVCz and the copolymer 1 and slightly higher band gap than PNVCz. The capacitive behaviours of the copolymer 11 were very close to PNVCz.

This study focuses on obtaining a green and conductive form of the copolymer of NVCz and MEKFR with the electrochemical method by using a white and insulator form of the same copolymer.

This work provides technical information for the synthesis of conducting copolymer of NVCz and MEKFR.

These copolymers may be in the field of PNVCz applications such as photoconductivity and corrosion inhibition.

Electroinduced Ce (IV) MEKFR redox system was applied for the polymerization of NVCz monomer to produce the copolymer 1. The conductive copolymer 11 was synthesized through electrochemical oxidative coupling of the carbazole groups of the copolymer 1.

The purpose of this paper is to synthesize polypyrrole/SiO₂ composite coating on 316 stainless steel (316SS) by cyclic voltammogram and preliminary do research about the valuable effects of SiO₂ particle incorporation within the polymer matrix.

This study is based on elaboration of coating by electrochemical process and of SiO₂ by a sol-gel process.

Electrochemical impedance studies revealed that compared with polypyrrole (PPy), PPy-SiO₂ coating acts as a more protective layer on 316SS against corrosion in 3.5 per cent NaCl. Scanning electron microscopy studies revealed that the PPy-SiO₂-coated 316SS showed more uniform and compact morphology.

To fully disperse SiO₂, a sol-gel method is used. Hydroxyl group is generated on the surface of inorganic particle by the sol-gel method, which improves the inorganic particle dispersion.

The purpose of this paper is to compare thick and thin film microstripline response to conducting overlay.

Study changes in transmission and reflection of both thick and thin film microstripline due to overlay of polyaniline (PANI) thin film on stainless steel and silver. PANI was deposited by electropolymerisation method using HCl and H₂SO₄.

Transmittance of both the thick and thin film microstripline decreases due to the PANI overlay and reflectance increases. Thin film microstripline is more sensitive to the type of conducting overlay than thick film microstripline. PANI deposited on silver is more absorbing than PANI deposited on stainless steel using HCl acid. The overlay makes the response of the microstripline more dispersive.

The increase in reflectance and decrease in transmittance can provide information about the type of overlay materials. There is need for newer materials which can replace traditional metals for microstrip components. PANI might serve this purpose.