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The purpose of this paper is to study the curing mechanisms, anticorrosive properties and protective mechanisms of three kinds of amine curing agents applied in a new kind of light colored water‐borne epoxy antistatic anticorrosive paint.

Using light color‐conductive mica, titanium oxides and environmentally‐friendly anticorrosive pigments in the two‐component water‐borne epoxy system, the light colored water‐borne antistatic anticorrosive paint was prepared. The molecular structure and curing mechanisms of the curing agents was analyzed by Fourier transform infra‐red spectroscopy, and the influence of the curing agents on anticorrosive properties and protective mechanisms was studied by electrochemical impedance spectroscopy.

The paints cured by the modified amine curing agent possessed optimal integrated properties with a coating surface resistivity of 10⁶ Ω and the best anticorrosive performance.

A novel light colored water‐borne epoxy antistatic anticorrosive paint cured by the optimal curing agent could be used in corrosion protection for oil tanks to replace the traditional oil‐based antistatic anticorrosive paints.

The objective of this work was to examine the anticorrosive behaviour of four different epoxy coatings, which were formulated with zinc pigments and were applied on pretreated steel panels exposed to deionised/deaerated water taken from the installations of the Greek Public Electricity Company, as well as to compare the results of this study with those of a relevant, previous work. The coating's performance was assessed by the measurement of the potentiodynamic polarisation resistance, by electrochemical impedance spectroscopy and the measurement of dielectric permittivity, during the deionised/deaerated water immersion tests. Additionally, accelerated salt spray tests were performed. All types of coatings tested exhibited a high protective performance. It was concluded that the epoxy system containing zinc dust was the most effective anticorrosion coating under the conditions relevant to this study.

The purpose of this study is to use polybenzoxazine (Pbz) functionalized ZrO₂ nanoparticles to synthesize polyurethane (PU)-PbZ/ZrO₂ nanocomposite. The results derived from the electrochemical impedance spectroscopy (EIS) and polarization studies indicated the superior anticorrosive activity of PU-Pbz/ZrO₂ nanocomposite coatings compared to those of plain PU coatings. The decreased corrosion current was detected on the scratch of the PU-Pbz/ZrO₂ nanocomposite-coated mild steel surface by scanning electrochemical microscopy (SECM) compared to other studied coatings. The superior anticorrosive and mechanical properties of the proposed nanocomposite coatings provide a new horizon in the development of high-performance anticorrosive coatings for various industries.

The Pbz functionalized ZrO₂ nanoparticles were characterized by Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDX) and thermogravimetric analysis (TGA) in terms of the structural, morphological and thermal properties of these coatings. A different formulation of coatings such as PU, PU-Pbz, PU-ZrO₂ and PU-Pbz/ZrO₂ were prepared and investigated for their corrosion protection performance on mild steel in natural seawater by electrochemical techniques. The surface morphological studies were done by SEM/EDX and XRD analysis.

The superior anticorrosive property of the proposed nanocomposite coatings provides a new horizon in the development of high-performance anticorrosive coatings for various industries. Addition of Pbz wrapped ZrO₂ nanoparticles into the PU coating resulted in the blockage of charge transfer at the metal/electrolyte interface, which reduced the dissolution of mild steel. It was revealed from the SEM/EDX analysis that the formation of the corrosion products at the metal/electrolyte interface behaved as the passive layer which reduced the dissolution of steel.

The inclusion of polybenzoxazine functionalized ZrO₂ nanoparticles to the polyurethane coating reinforces the barrier and mechanical properties of PU-Pbz/ZrO₂ nanocomposite, which is due to the synergistic effect of ZrO₂ and Pbz.

The paper studies the effect of modification of zinc orthophosphate on the anticorrosion efficiency thereof in organic coating. The zinc orthophosphate dihydrate and tetrahydrate and the reaction of phosphate anion with hydroxyl binder groups are compared. The highest anticorrosion efficiency is reached with pigments which are modified by organic corrosion inhibitors. The highly water soluble phosphate pigments reduce the anticorrosion coating properties. The effect of cation in phosphate pigments on the corrosion inhibition was confirmed.

To investigate the properties of coatings containing various types of fillers from the point of view of their physical‐mechanical properties and anticorrosive properties.

Research used fillers of different types varying in morphology and/or chemical composition; these were then compared with selected pigments and zinc phosphate, an anticorrosive pigment. The following parameters were observed for all of the fillers and pigments: oil absorption, CPVC value, density, extract pH, specific surface, particle size, and water‐soluble substances. The morphology of particles was observed by means of an electron‐scanning microscope. The coatings of these fillers and pigments were formulated on an epoxy resin binder basis cured with a polyamine hardener. The coatings prepared were subjected to the measurement of physical‐mechanical properties such as hardness and deepening resistance, flex resistance, adhesion to steel, and the gloss of the coatings. The coatings containing the fillers and pigments studied underwent corrosion tests in a condenser chamber and in a salt‐spray cabinet.

The results obtained through the tests allowed the selection of the optimum filler for an epoxy coating with barrier anticorrosive properties. As per respective findings, some fillers in these coatings of significant thickness can be comparable to their zinc phosphate counterparts.

The anticorrosive properties of the coatings studied can also be tested in paints by means of atmospheric exposure, for instance, with the aid of a Florida test.

The findings are helpful towards applications in the formulations of anticorrosive coatings of significant thickness that offer an effective barrier mechanism.

The research presents the results of the properties of a whole range of industrially employed fillers and pigments contained in paints. Based on this study, the formulation of steel protecting coatings can be optimised.

Magnesium ferrite pigments were evaluated as active pigments in anticorrosive water‐borne paints. The study includes the use of two different anticorrosive pigment volume concentration (APVC), 15 and 25 per cent and fixed the Q value (the pigment volume concentration/critical pigment volume concentration ratio) in both paint formulations. Epoxy and acrylated alkyd resins were used as binders. The paints were evaluated by accelerated salt spray tests, corrosion tests in condensed water and sulphur dioxide chambers and electrochemical evaluations. The results obtained were compared with reference paints containing zinc ferrite and zinc phosphate pigments. Ferrite pigments passivate the carbon steel directly in the case of neutral epoxy resin binder or indirectly due to the soaps produced as a result of reaction with the acidic acrylated alkyd resin binder. A lower per cent, i.e. 15 per cent of APVC was found to be sufficient to provide satisfactory anticorrosion protection.

The spinel‐type pigments of a general formula corresponding to AB₂O₄ containing as A the Mg²⁺ or Zn²⁺ ions and as B the Fe³⁺ or Al³⁺ ions or combinations of both the A and B were prepared and investigated with respect to their anticorrosive action as pigments in organic coatings. For the same purposes, comparative pigments, known for their efficiency as the metal‐corrosion inhibiting ingredients in similar formulations, were used. Further evaluation was carried out on the properties of condensed phosphates as anticorrosion pigments. The results obtained showed the high anticorrosion action of the spinel‐type pigments.

This work aims to study the corrosion protection of laboratory‐prepared micaceous zinc ferrite (MZF) pigment in anticorrosive paints for steel.

Acrylic‐modified alkyd coatings, based on MZF pigment, micaceous iron oxide (MIO) and zinc ferrite (ZF) pigments, were prepared at different pigment volume concentrations “PVCs” to the critical pigment volume concentrations “CPVCs” ratio, which denoted hereafter by A. Scanning electron microscope, weight loss measurements, water vapour transmission (WVT) and immersion in 3.5 per cent salt solution as well as physico‐mechanical properties were performed to evaluate the paints anticorrosive performance.

WVT and corrosion protection can be affected by the PVC/CPVC ratio for all systems. At any particular PVC, the barrier property of the pigment was the main factor affecting the WVT and corrosion protection. MZF pigment protected the carbon steel physically through barrier action and chemically by the reaction with the acidic acrylic‐modified alkyd resin to produce soaps which passivate the substrate.

Novel MZF paint could be used with optimum percentage in anticorrosive paints for steel protection especially in humid and coastal regions.

The performance of epoxy coating on metal substrate at low temperature and high humidity application has adverse effect on cure rate, film properties and adhesion. In recent years, several advanced amine cross-linking agents having superior curing ability at low temperature application environment have been introduced. The aim of this paper is to study the properties of epoxy-based coating cured with different cross-linking agents designed for low temperature application at different environmental conditions.

Series of cross linking agents such as modified cycloaliphatic amine (H1), polyamine adduct (H2), modified aliphatic ketamine (H3), phenalkamine (H4) and phenalkamide (H5) have been studied to evaluate their performance in epoxy compositions when cured at four environmental conditions, i.e. at ambient and sub-ambient temperatures with 60 and 90 per cent relative humidity, respectively. The effect of curing conditions was investigated by evaluating different physico-mechanical properties. Dynamic mechanical analyser technique was used to determine glass transition temperature (T_g) and cross-link density (ρ) of coatings. Anticorrosive properties of coatings also have been studied by electrochemical impedance spectroscopy.

The outcome of this study is expected to generate new insight into the curing behaviour of epoxy coating using different cross-linking agents which are recommended for low temperature application. Optimum physico-mechanical and corrosion resistance properties have been obtained by phenalkamine curing agent at low temperature and high humidity condition.

This study is an experimental approach to select the better cross-linking agent for low temperature application. Different test conditions were measured for understanding the performance of epoxy coating cured at different environmental condition.

The understanding reaction mechanism of the epoxy resin with cross-linking agent at different environmental condition is the great challenge and is hardly investigated in the literature. Therefore, in this research, the influence of climatic conditions and type of cross-linking agents on curing behaviour of epoxy-based coating was investigated.

The present study aims to demonstrate the use of renewable source in the preparation of polyurethane (PU) coatings and mitigation of corrosion of mild steel using nano zinc phosphate. Results indicated improvement in the properties of the PU coatings, especially anticorrosive properties by the addition of nano zinc phosphate.

Renewable-source-based polyestermyristamide polyol was synthesized using myristic acid as a starting material. The synthesis of polyol was carried by amidation as well as by esterification by a one-pot route. The structure of the prepared polyestermyristamide was confirmed with the support of end-group analysis and spectral study. PU coatings were prepared from synthesized polyestermyristamide polyol and used to protect metal substrate against corrosion. Corrosion properties of the prepared PU were found to be lower; hence, to improve the performance of these coatings, nano zinc phosphate was added to the coatings. The nano zinc phosphate was synthesized in the laboratory by reported sonication method and analyzed for morphology by scanning electron microscopy. Performance of coatings was studied with respect to effect of percentage nano zinc phosphate on thermal stability, mechanical properties and chemical resistances of PU coatings.

The combination of zinc phosphate nano rods and particles in myristic acid-based PU coatings provided substantial corrosion barrier properties to the coatings. Different per cent of the synthesized zinc phosphate nano rods and particles were loaded into the matrix, and corresponding coatings were estimated for corrosion resistance, thermal and chemical properties. Immersion study of the coated panels in 3.5 per cent NaCl solution showed good corrosion resistance for both PU coatings containing 2 and 3 per cent nano zinc phosphate.

This paper has provided the solution to replace existing petroleum-based raw materials with myristic acid as a renewable source in preparing PU coatings. Conventional coatings act as physical barriers against aggressive species but do not have ability to perform as permanent impassable to corrosive species. Hence, nano-sized zinc phosphate is used as corrosion inhibitor in to the synthesized PU coatings for enhancing anticorrosive performance.

In the paper, polyesteramide polyol is synthesized using renewable-source-based material, i.e. myristic acid to replace existing petroleum-based acid as a greener approach. Normally, vegetable oils are preferred as they have such kinds of polyols. The polyesteramide reaction is one pot that avoids the extra steps required in the synthesis. Further, it has been found that the pristine renewable coatings are unable to fully protect subtract from corrosion, whereas an addition of the nano-size zinc phosphate has enhanced the corrosion properties of the coatings.