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The synergistic influence caused by iodide ions on the inhibition of corrosion of mild steel in 0.5M H₂SO₄ in the presence of n‐hexyl amine (n‐HA) has been studied using potentiodynamic polarization, linear polarization and a.c impedance technique. n‐HA accelerates the corrosion of mild steel at lower concentrations but inhibits the corrosion at higher concentrations. The addition of iodide ions enhances the inhibition efficiency to a considerable extent. The adsorption of this compound is found to obey Temkin’s adsorption isotherm. The increase in surface coverage in the presence of iodide ions indicates that iodide ions enhance the adsorption of n‐HA on the metal surface. Defines and evaluates synergism parameter (S_I). Values of the parameter which are more than unity indicate the fact that the enhanced inhibition efficiency in the presence of iodide ions is only due to synergism and there is a definite contribution from the inhibitor molecule. n‐HA is then adsorbed by coulombic interaction on the metal surface, where iodide ions are already adsorbed, and thus reduces the corrosion rate.

Recent developments indicate that the polymer coatings used to protect steel structures from corrosive environments are rarely one‐component systems. Polymeric blends used to protect the structures are a mixture of at least two polymers or copolymers. The heterophase polymer blends are known as polymer‐polymer composites (PPC). The advantages of PPC coatings in comparison to multicoat systems are high thickness per coat, excellent protection and superior layer adhesion. Presents a study in which a poly (epoxy‐chlorinated rubber‐silicone) PPC coating was prepared and its chemical resistance properties in acid, alkali and neutral solutions were studied. Different combinations of these three binders were also prepared in toluene:acetone solvent mixture and the chemical resistance properties of these PPCs were evaluated in comparison with the corresponding multicoat system with the same thickness. Finds that the PPCs show superior properties when compared to multicoat systems. Studies the electrochemical behaviour such as potential, resistance and capacitance of the PPCs and the multicoat systems on steel substrate in sodium chloride solution and finds that the PPCs have higher resistance value than the multicoat systems. Based on the experimental results, concludes that a single coat of PPC can be recommended for protecting the steel structures from chemical and marine environments, instead of using conventional three‐ or four‐coat systems based on the same or different film formers.

Corrosion is an important problem to be taken care in terms of economic and ecological aspects. The aim of this paper is to identify the methods of protection and selection of materials for corrosion protection.

A novel attempt has been made to formulate a hybrid composite paint system using silicone (S2) and polyester (P3) resins. These resins have been blended in different weight ratios to develop binder for protection coatings. Cross‐hatch test, impact resistance test, thermal characterization, impedance measurement and potential‐time measurement were conducted on binder coated steel panels. Heat resistance test was carried out using ASTM D2485 standards.

The results showed that physical and mechanical properties of the coatings have been improved by the addition of silicone into the polyester matrix. The binder system developed using 50 wt per cent polyester and 50 wt per cent silicone showed good physical, mechanical properties and high thermal resistance. The maximum coating resistance of the coatings after 30 days exposure was found to be 9.7×10⁶ Ω and the coating can withstand high temperature up to 473 K.

The development of different types of coatings will be useful to achieve higher protection performance. The combinations of different resins and pigments have to be analysed and selected suitable compositions.

The objective of this study is to develop coating system with different resins to achieve better performance and reduce the cost of paint materials. It may be useful for the industries to move forward with new formulation using multicomponent coating materials. A critical combination of the above resins offers better protection for steel structures from high temperature corrosive environments.

The formulation of coating material using two different resins and a single curing agent is a novel approach in this research. This type of research will open new ideas of formulating different coatings using various types of resins. In high temperature corrosion environment, the coatings which is commonly used is silicone based and the price of the raw material is very high therefore to reduce the cost of the raw material, the silicone resin is being blended in different ratios with organic resin to obtain an optimum ratio which can be applied to overcome high temperature corrosion on steel panels.

The purpose of this paper is to investigate the inhibition effect of 2‐aminoethane thiol hydrochloride, 2‐cystamine dihydrochloride, 2,3‐dimercapto‐1‐propanol, 1,2‐ethanedithiol, and the synergistic effect of these compounds with halide ions (Cl⁻, Br⁻, I⁻) and with some metal cations (Co^2 +, Ni^2 +, Cu^2 +, Zn^2 +).

The inhibiting effect of the studied thiols on the corrosion of carbon steel in 0.5 M H₂SO₄ solution were investigated using potentiodynamic polarisation, electrochemical impedance spectroscopy and linear polarisation methods.

The inhibition action of thiols depends mainly on the type of the heteroatom present in the inhibitor molecule. The increase in inhibition efficiencies with increase in inhibitor concentration revealed that the studied compounds were adsorbed onto steel surfaces and the adsorption mechanism obeyed the Langmuir adsorption isotherm. Polarisation curves indicated that thiols containing both N and S atoms in their structure behaved as mixed type inhibitors, while thiols containing only an S atom in their structure acted essentially as anodic inhibitors. The increase in the inhibition efficiencies of thiols with the addition of halide ions indicates that halides play important role in the adsorption process. The synergistic effect of the studied metal cations could be explained by the adsorption of complex ions formed from thiol molecules and metal cations.

This paper provides useful information about the relationship between inhibition efficiencies and the structures of thiols and clarifies the mechanism of the synergistic effects of some halides and some metal cations.

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.

The purpose of this paper is to investigate the heat resistance properties of silicone‐acrylic hybrid system on cold rolled mild steel panel.

The presence of Si−C bonds in hydroxyl functional solid phenyl‐methyl silicone should be able to improve heat resistance properties of silicone‐acrylic polyol coating. Different weight ratios of silicone resin and acrylic polyol resins were blended in order to obtain the composition for optimum thermal properties. Thermal stability of silicone based protective coatings has been investigated by means of potential time measurement (PTM) and electrochemical impedance spectroscopy (EIS) techniques.

The blending of silicone intermediate resin with acrylic polyol resins. The coating consisting of 30 per cent silicone resin and 70 per cent acrylic resin showed significant improvement of heat resistivity compared to pure acrylic polyol resins on cold roll mild steel panels. This study demonstrates an interesting correlation between PTM and EIS studies.

Findings may be useful in the development of heat resistant paints.

The blending method provides a simple and practical solution to improve the heat resistance properties of acrylic polyol resins.

Durability and functionality of the coating, critically depend on the strength and adhesion properties of the materials. This may be a useful source of information for the development of organic‐inorganic coatings.

The purpose of this paper is to synthesise polyaniline‐SiO₂ (PANI‐SiO₂) composites and investigate the anticorrosion properties of polyaniline‐SiO₂‐containing coating on Mg‐Li alloy.

The PANI‐SiO₂ composites were prepared by in situ chemical oxidative polymerisation in phosphoric acid medium. The PANI‐SiO₂ composites were characterised by Fourier transform infrared, X‐ray diffraction and scanning electron microscopy techniques. The coating consisted of PANI‐SiO₂ composites and epoxy resin was formed on Mg‐Li alloy. The anticorrosion properties were investigated by open circuit potentials (OCP), electrochemical impedance spectroscopy (EIS) and potentiodynamic polarisation curves.

The results indicated that the PANI‐SiO₂‐containing coating on Mg‐Li alloy demonstrated good anticorrosion properties in 3.0 wt% NaCl solution. It has been found that the OCP of PANI‐SiO₂‐containing coating were able to maintain more noble potential values in comparison to pure epoxy coatings in 3.0 wt% NaCl solution. EIS analysis indicated that the resistance of PANI‐SiO₂‐containing coating was more than 10⁶ Ω cm² in 3.0 wt% NaCl solution in immersion process. Furthermore, the corrosion current of PANI‐SiO₂‐containing coating on Mg‐Li alloy showed a significant reduction.

Previous reports on PANI‐SiO₂ composites were mostly focused on their conductivity and optical properties and there are few studies so far on their anticorrosion properties as protective coatings for Mg‐Li alloy.

This article presents a study of the major corrosion problems of steel structures in rubber and palm oil mill industries in Malaysia. Such structures, improperly coated with protective treatment (commercial coatings) were easily damaged by corrosion due to the environment within a month’s time. In order to prevent these types of corrosion problems, the epoxy‐silicone resin based paints were developed. The performance of the coatings were evaluated. These studies confirm the fact that the epoxy‐silicone coatings are effectively useful for protection of steel structures in these industries for considerably longer times.

Describes the preparation and properties of heat‐resistant paints based on an epoxy blended with rhodorsil silicone resin. Studies the heat‐resistant properties as per ASTM standard (D 2485‐91). Also determines the properties of the liquid paint and coated metal panels. Assesses the thermal degradation of the coating both by electrochemical (potential vs time and EIS) and structural (SEM) means. Results reveal that the coating is stable up to 200°C on a mild steel surface and degradation takes place only beyond this temperature. Discusses the failure mechanism of the above coating in light of the experiment’s results.

Coatings with outstanding chemical and physical properties can be obtained from two‐pack formulations without stoving. The epoxy resin was cured with different amine‐based compounds, such as polyamide (PA), the aniline copolymer of triethanolamine titanate and aniline formaldehyde. The thermal resistance properties of the cured films were analysed using the thermo‐gravimetric method. This study also examined the effect of coating resistance of 3 per cent sodium chloride solution by means of electrochemical impedance measurements. Coatings that included the epoxy triethanolamine titanate showed superior behaviour, compared to the other two systems tested. This hardener can be recommended instead of using conventional PA and polyamidoamide hardeners for epoxy two‐pack systems that are to be used to protect the steel structures from highly corrosive chemical and marine environments.