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The purpose of this study is to compare the inhibitive effect of polyaniline (PAni) and N-cetyl-N,N,N trimethyl ammonium bromide (CTAB)-stabilized PAni in a hydrochloric acid (HCl) medium.

PAni has been deposited potentiodynamically on mild steel in the presence of CTAB as a stabilizing agent to achieve high corrosion inhibition performance by the polymer deposition. The corrosion inhibition studies of CTAB-stabilized PAni inhibitor in 0.1 M HCl acidic solution was carried out by electrochemical methods, namely, open-circuit potential, potentiodynamic polarization and electrochemical impedance spectroscopy technique.

The results of electrochemical studies have shown that the CTAB-stabilized PAni inhibitor has higher corrosion efficiency than PAni on mild steel in 0.1 M HCl solution. The maximum per cent efficiency evaluated using the potentiodynamic polarization method is approximately 91.9.

CTAB-stabilized PAni has never been studied as a corrosion inhibitor for mild steel in an acidic medium. The investigations demonstrate relatively the better corrosion inhibition efficiency and high dispersion of the polymer in the acidic medium.

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.

Copper and its alloys are widely used in industries because of their good resistance to corrosion and are often used in cooling water systems. Brass has been widely used for shipboard condensers, power plant condensers and petrochemical heat exchangers. Brass is susceptible to the corrosion process known as dezincification by means of which brass looses its valuable physical and mechanical properties leading to failure of structure. The aim of this investigation was to control the dezincification of brass in 3 per cent NaCl solution using benzotriazole (BTA) derivatives.

BTA derivatives namely 1‐hydroxymethylbenzotriazole (HBTA) and N,N‐dibenzotriazol‐l‐ylmethylamine(ABTA) were synthesised and their inhibition behaviour on brass in 3 per cent NaCl solution was investigated by the weight‐loss method, potentiodynamic polarisation, electrochemical impedance and solution analysis techniques. The morphology of the brass after corrosion in the presence and absence of the BTA derivatives was examined using scanning electron microscopy (SEM).

Potentiodynamic polarisation studies showed that the BTA derivatives investigated were mixed type inhibitors, inhibiting the corrosion of brass by blocking the active sites of the brass surface. Changes in the impedance parameters (charge transfer resistance and double layer capacitance) were related to the adsorption of BTA derivatives on the brass surface, leading to the formation of a protective film. Solution analysis revealed that the BTA derivatives excellently controlled the corrosion of brass. SEM micrographs showed the formation of compact surface film on the brass surface in the presence of inhibitors, thereby providing better corrosion inhibition.

Contributes to research on corrosion protection for copper and its alloys.

This paper aims to assist higher education institutions (HEIs) in their decision-making process to define initiatives and foster research projects contributing to sustainable development (SD) and minimizing the deficits found in the municipalities.

A documental analysis was performed to select HEIs and Brazilian regional development indicators. Then, the assessment of the sustainable and institutional performance of Brazilian municipalities that have HEIs consisted of three parts: clustering with an unsupervised machine learning model, ranking with a hybrid multi-criteria decision making method and visualization of sustainability performance with the dashboard.

The critical analysis of institutional and sustainability indicators contributes to a more active role of HEIs in matters of social responsibility, with a more holistic view of the performance and quality of municipal education. Furthermore, this critical analysis creates a scenario where HEIs can develop public policy proposals in partnership with the government to mitigate the main issues identified.

With this study, HEIs will be able to direct their actions to minimize the deficits found in the municipalities, consolidating their social responsibility.

This study proposes a new decision-support tool with a dashboard of indicators so that HEIs can foster research projects with a focus on regional SD.

To evaluate the performance of a reactive diluent, nonylphenyl methacrylate (NPM) for toughness improvement of bisphenol‐a‐glycidyl dimethacrylate (BisGMA) and to optimise the results of such a modification.

To achieve desirable rheological and physico‐mechanical properties of BisGMA/NPM network, various compositions were made by incorporating different concentrations of NPM. The effect of concentration on the impact and the adhesive strengths of the unmodified and modified BisGMA networks were characterised.

The modification of BisGMA resin using NPM showed significant enhancement of the impact and the adhesive strengths over the unmodified one. The modification caused a chemical linkage between NPM and BisGMA resin, which led not only to a phase separation but also to establishing the intrinsically strong chemical bonds across the NPM phase/resin matrix interphase, which was responsible for the improvement of the impact and adhesive strength. The optimum results were obtained at 10/h (parts per 100 parts of BisGMA resin) of modifier.

The reactive diluent, used in the present context was synthesised from nonyl phenol, methacrylic acid and benzoyl chloride in methyl ethyl ketone using triethylamine as base.

The method of modification developed provides a simple and practical solution for improving the rheological and physico‐mechanical properties of BisGMA network.

The method developed is a novel one for enhancing the rheological and physico‐mechanical properties of BisGMA network diluted with NPM resin and may find numerous applications in surface coating and adhesive.

The aim of this research was to develop corrosion protection systems for reinforced concrete structures under chloride attack. Benzotriazole (BTA) and BTA derivatives were used as corrosion protection materials for the steel.

The effect of BTA and four other BTA derivatives on the corrosion resistance of steel in simulated concrete pore (SCP) solutions was studied. BTA derivatives were used as two separate protection systems: inhibition and pickling protection systems. The experiments were performed in SCP solutions which simulated concrete with and without severe chloride attacks. Electrochemical techniques, i.e. potentiodynamic polarization and electrochemical impedance, and Fourier transform infrared spectroscopy (FTIR) were used to assess the steel corrosion protection systems.

The potentiodynamic polarization studies showed an increase in the pitting potential for all protection systems tested. In addition, a large increase in the steel solution interfacial resistance was observed by electrochemical impedance studies (EIS) due to the formation of steel‐BTA derivatives complex on the surface. This film was formed on the steel surface with either mono‐or bi‐dentate bonds between the triazolic nitrogen ring and the steel surface as shown by the FTIR.

BTA derivatives provided good protection for steel in SCP solutions, indicating their applicability in reinforced concrete structures. However, tests using reinforced concrete samples are required to study possible interactions between steel, BTA derivatives and concrete constitutes, e.g. sand, gravel, cement and chemical admixtures. These BTA‐based systems also should be studied under carbonation attack.

BTA derivatives provided a good protection for steel in the SCP solutions, and this indicates the applicability to use them in reinforced concrete structures.

Polyurethane concrete (PUC), as a new type of steel bridge deck paving material, the bond-slip pattern at the interface with the steel plate is not yet clear. In this study, the mechanical properties of the PUC and steel plate interface under the coupled action of temperature, normal force and tangential force were explored through shear tests and numerical simulations. An analytical model for bond-slip at the PUC/steel plate interface and a predictive model for the shear strength of the PUC/steel plate interface were developed.

The new shear test device designed in this paper overcomes the defect that the traditional oblique shear test cannot test the interface shear performance under the condition of fixed normal force. The universal testing machine (UTM) test machine was used to adjust the test temperature conditions. Combined with the results of the bond-slip test, the finite element simulation of the interface is completed by using the COHENSIVE unit to analyze the local stress distribution characteristics of the interface. The use of variance-based uncertainty analysis guaranteed the validity of the simulation.

The shear strength (τ_f) at the PUC-plate interface was negatively correlated with temperature while it was positively correlated with normal stress. The effect of temperature on the shear properties was more significant than that of normal stress. The slip corresponding to the maximum shear (D₁) positively correlates with both temperature and normal stress. The interfacial shear ductility improves with increasing temperature.

Based on the PUC bond-slip measured curves, the relationship between bond stress and slip at different stages was analyzed, and the bond-slip analytical model at different stages was established; the model was defined by key parameters such as elastic ultimate shear stress τ₀, peak stress τ_f and interface fracture energy G_f.

To synthesise and characterise homo and copolymer of 4‐nonylphenyl methacrylate (NPMA) and styrene and to determine monomer reactivity ratios by the application of conventional linearisation methods such as Finemann‐Ross (F‐R) and Kelen‐Tudos (K‐T) methods.

New methacrylic monomer, NPMA with a pendant nonylphenyl group was copolymerised with styrene. All monomer and polymers (homo and copolymer) are characterised and subsequently the monomer reactivity ratio was determined.

The monomer reactivity ratios were determined by application of conventional linearisation methods such as F‐R (r₁=0.41±0.05; r₂=3.47±0.31), K‐T (r₁=0.43±0.19; r₂=3.54±0.09) methods. The thermogravimetric analysis (TGA) of the polymer in nitrogen reveals that it posses very good thermal stability in comparison to alkyl acrylates due to presence of pendant nonylphnyl group.

New methacrylic monomer, NPMA was synthesised by reacting nonylphenol dissolved in methyl ethyl ketone (MEK) with methacryloyl chloride in the presence of triethylamine as a base. Copolymers of NPMA with styrene were synthesised in MEK using benzoyl peroxide (BPO) as initiator under nitrogen atmosphere at different feed composition.

The method developed is a simple and easy method of copolymerisation of styrene with methacrylate to obtain copolymer of better properties.

The method developed is a novel method for enhancing the thermal, as well as surface adhesion, properties which has several applications in surface coatings and adhesives.

This paper aims to evaluate the inhibition efficiency of thiadiazole derivatives, such as 2,5-dimercapto-1,3,4-thiadiazole (DMTD), 5-methly-2-mercapto-1,3,4-thiadiazole (MMTD) and 2,5-dithiododecyl-1,3,4-thiadiazole (DDTD), in 50 mg/L hydrogen sulfide for silver strip.

Evaluation was carried out by corrosion-inhibiting test, electrochemical measurement and surface analysis techniques. 3D surface profiler, atom force microscopy, scanning electron microscopy and energy-dispersive X-ray analysis were applied and finally confirmed the existence of the adsorbed film.

The electrochemical measurement showed that the inhibition efficiency increases with increasing inhibitor concentration in 50 mg/L hydrogen sulfide solution, while the corrosion rate and the corrosion current decrease. Weight-gained measurements also indicated that inhibitor decreases the corrosion rate in the studied solution. The adsorption of DMTD and MMTD on the silver surface obeys Temkin’s adsorption isotherm, but the adsorption of DDTD follows Langmuir’s adsorption isotherm. That means that the inhibition mechanism is different between DMTD, MMTD and DDTD. The ΔG0_ad values of DMTD, MMTD and DDTD were −37.47, −37.29 and −38.69 kJ/mol, respectively. It showed that there was an adsorption bond between silver surface and inhibitor, and the adsorption belongs to chemical adsorption.

The inhibitors have an excellent inhibition efficiency, and the best inhibition efficiency is 91.76 per cent. Inhibitors can effectively inhibit metal corrosion in the oil and gas.

Effects of corrosion are very dire and mitigation of corrosion holds prime importance. Protective coatings play major role in preventing corrosion of metals and coating application is the most convenient, economical and quick solution. The purpose of the study is development of protective coatings to effectively mitigate corrosion of metal components.

A high-performance anticorrosion coating was prepared using multiple monomers and paste of functional and reinforcing fillers with extenders to protect metal components from corrosion in aggressive environmental conditions. The structures of copolymers synthesized with multiple monomers were studied by the NMR and FT-IR spectroscopic techniques. The percentage conversion of different proportions of various monomers was estimated using gas chromatography technique. The functional paste to impart superior anticorrosion properties was prepared using various functional and reinforcing fillers. The final coatings were prepared by mixing these resins with functional paste in various proportions.

The prepared anticorrosion coating was tested for high-performance mechanical and chemical properties and it was witnessed that the said coating offered desired performance properties needed for protecting metal components from corrosion.

As such it is overcoming drawbacks of two pack systems and thus has almost no limitations or implications for application on metal substrate.

Being formulated as a single pack, it is free from drawbacks otherwise involved in two pack system of conventional paints. The coating system developed is very easy to apply using conventional tools, namely, brush, spray and roller techniques. The formulation is made in such a way that it has fast-drying properties. Makes painting or coating operations cost effective and confirm the performance.

The findings of the research have anticorrosion nature that can enhance the life span of the substrates. It is specially designed for metal substrate and can protect metal substrate from corrosion in most aggressive conditions. Thus, it helps to reduce losses due corrosion and increase safety of metal structures and human being as well. As it is based on conventional material but with new formulation and technology, it has commercial possibilities to explore.

Unlike conventional protective coating systems, the said coating offered disruptive features like single pack systems and fast drying at ambient temperature along with high-performance properties. The coating formulation was observed to have a great importance in industry for effective corrosion mitigation and to reduce losses due to corrosion.