Search Results (34)

Acrylic resin is a polymer with strong crosslinking density and strength, and it is commonly used as a matrix in water-based coatings. Barium europium phosphate (Ba₃Eu(PO₄)₃) is a novel functional filler that is expected to provide anti-corrosive effects to coatings. In this study, Ba₃Eu(PO₄)₃ was prepared by the high-temperature solid-phase method and applied to acrylic anti-corrosion coatings. The influence of the molar ratio of reactants on Ba₃Eu(PO₄)₃ purity was studied. The anti-corrosion performance of the coating was investigated. It was found that, when BaCO₃:Eu₂O₃:(NH₄)H₂PO₄ = 3:0.5:3 and the reaction was carried out at 950 °C for 1000 min, high-purity Ba₃Eu(PO₄)₃ can be obtained, according to XRD and EDS tests. SEM shows that Ba₃Eu(PO₄)₃ has good crystal morphology and a porous morphology. TEM revealed that its structure was intact. When Ba₃Eu(PO₄)₃ was added to a relative resin content of 5 wt%, the anti-corrosion performance of the coating was the best after 168 h, with the lowest Tafel current density of 9.616 μA/cm² and the largest capacitance arc curvature radius. The salt spray resistance test showed that the corrosion resistance of the 5 wt% Ba₃Eu(PO₄)₃ coating was also the best, which is consistent with the results of the electrochemical test. Ba₃Eu(PO₄)₃ as a pigment and filler can effectively improve the anti-corrosion performance of water-based industrial coatings. Full article

Marine biofouling, the process of marine microorganisms, algae, and invertebrates attaching to and forming biofilms on ship hulls, underwater infrastructure, and marine equipment in ocean environments, severely impacts shipping and underwater operations by increasing fuel consumption, maintenance costs, and corrosion risks, and by threatening marine ecosystem stability via invasive species transport. This study reports the development of a hydrogel-metal-organic framework (MOF)-quorum sensing inhibitor (QSI) antifouling coating on 304 stainless steel (SS) substrates. Inspired by mussel adhesion, a hydrophilic bionic hydrogel was first constructed via metal ion coordination. The traditional metal ion source was replaced with a zeolitic imidazolate framework-8 (ZIF-8) loaded with 2-(5H)-furanone (HF, a QSI) without altering coating formation. Physicochemical characterization using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), the Brunauer–Emmett–Teller (BET) method, and the diffraction of x-rays (XRD) confirmed successful HF loading into ZIF-8 with intact crystal structures. Antifouling tests showed HF@ZIF-8 enhanced antibacterial inhibition against Staphylococcus aureus (97.28%) and Escherichia coli (>97%) and suppressed Chromobacterium violaceum CV026 pigment synthesis at 0.25 mg/mL (sub-growth concentration). The reconstructed PG/PVP/PEI/HF@ZIF-8 coating achieved 72.47% corrosion inhibition via synergistic anodic protection and physical shielding. This work provides a novel green approach for surface antifouling and drag reduction, highlighting MOF-loaded QSIs as promising additives to enhance the antifouling performance of hydrogel coatings, anti-corrosion performance, and QSI performance for sustainable marine engineering applications. Full article

Coating systems used for anticorrosion protection usually consist of a primer, intermediate layers, and topcoats. Zinc-rich primers, which serve as cathodic and barrier protection, are widely used for the corrosion protection of steel structures. Due to the fact that the functioning of the above-mentioned coatings is related to the conduction of galvanic current, these types of coatings are highly pigmented with zinc (up to 80 wt% in the dry coating). This may result not only in a deterioration of the performance of the coating system but also have a negative impact on the environment. Taking the above into account, solvent-based and water-based organic epoxy primers with zinc content reduced to approximately 50% have been developed. Zinc pigments of different shapes and with different surface treatments were used in the primers, as well as pigments without chemical treatment but with the addition of nanoparticles. It was found that, depending on the type of zinc pigment, both the developed solvent-based and water-based primers demonstrate good protective properties comparable to traditional zinc-rich coatings. Water-based paints tend to absorb more moisture compared to solvent-based systems, but their water uptake reversibility is limited. Moreover, the organic treatment of zinc flakes helps to improve this water uptake reversibility, improving the mechanical properties of coatings. Full article

There are a large number of steel components in substations/converter stations whose performance is seriously affected by being exposed to environmental corrosion and fire, endangering the operation of the substation/converter station. The current protective measures for steel components in substations/converter stations primarily involve the application of anti-corrosion and fireproof coatings. However, these coatings can easily peel off, resulting in a significant loss of their protective effectiveness. In response to this challenge, a new type of silicone-modified epoxy resin substrate has been synthesized by chemically grafting silicone resin onto epoxy resin segments, which retains the high adhesion of epoxy resin while enhancing its weather resistance. The use of synthesized nano zinc oxide-modified graphene oxide as a fireproof filler significantly improves the physical barrier effect and corrosion resistance of the coating. Additionally, the innovative addition of new metal anti-corrosion active pigments improves the adhesion and impermeability of the coating. Therefore, a steel structure coating for substations/converter stations with both fire and corrosion prevention functions has been developed. Standard tests conducted by national institutions have shown that the coating meets the performance requirements. Full article

This work deals with the coating properties of synthetic latices comprising two kinds of polymers, specifically polyacrylate and polypyrrole, which were simultaneously formed by semi-continuous emulsion polymerization using a “one-pot” synthesis strategy. In this procedure, both the emulsion polymerization of acrylate monomers and the oxidative polymerization of pyrrole occurred concurrently in one reactor. Polyacrylate latices differing in polypyrrole loading were prepared by applying various dosages of pyrrole, specifically 0, 0.25, and 0.50, based on the fraction of acrylate monomers. The effect of the in situ incorporated polypyrrole component (having the nature of submicron composite polypyrrole-coated polyacrylate latex particles) on the physico-mechanical properties and chemical resistance of the resulting heterogeneous coating films was investigated. The interaction of incorporated polypyrrole and anti-corrosion pigments (see ZnS, Zn₃(PO₄)₂, ZnFe₂O₄, MoS₂, and ZnO) on the corrosion resistance of coatings was evaluated by using the electrochemical linear polarization technique. The polyacrylate latex prepared with the lowest polypyrrole loading (achieved by polymerizing 0.25 wt. % of pyrrole related to acrylic monomers) was found to be the optimum binder for waterborne anticorrosive coatings based on their properties and protective function. Their compatibility with the selected types of pigments was studied for these latex binders. In addition, their influence on the anti-corrosion efficiency of polyacrylate paint films was evaluated using the linear polarization electrochemical technique. For high corrosion resistance, the ZnS and MoS₂ pigments, showing compatibility with polyacrylate latices containing the polypyrrole component, proved to be advantageous. Full article

The concept of intelligence has many applications, such as in coatings and cyber security. Smart coatings have the ability to sense and/or respond to external stimuli and generally interact with their environment. Self-healing coatings represent a significant advance in improving material durability and performance using microcapsules and nanocontainers loaded with self-healing agents, catalysts, corrosion inhibitors, and water-repellents. These smart coatings can repair damage on their own and restore mechanical properties without external intervention and are inspired by biological systems. Properties that are affected by either momentary or continuous external stimuli in smart coatings include corrosion, fouling, fungal, self-healing, piezoelectric, and microbiological properties. These coating properties can be obtained via combinations of either organic or inorganic polymer phases, additives, and pigments. In this article, a review of the advancements in micro/nanocapsules for self-healing coatings is reported from the aspect of extrinsic self-healing ability. The concept of extrinsic self-healing coatings is based on the use of capsules or multichannel vascular systems loaded with healing agents/inhibitors. The result is that self-healing coatings exhibit improved properties compared to traditional coatings. Self-healing anticorrosive coating not only enhances passive barrier function but also realizes active defense. As a result, there is a significant improvement in the service life and overall performance of the coating. Future research should be devoted to refining self-healing mechanisms and developing cost-effective solutions for a wide range of industrial applications. Full article

This study explores a new approach for corrosion protection of carbon steel, focusing on the application of polymeric coatings. Anticorrosive pigments were synthesized by loading 2-Mercaptobenzothiazole into zirconium oxide particles, and then an epoxy coating was applied on a steel substrate to analyze the corrosion inhibition activity. Analytical techniques like FTIR and XRD confirmed the successful loading of corrosion inhibitors onto zirconium dioxide nanoparticles (ZrO₂), revealing changes in chemical bonding and structural patterns. Scanning electron microscopy (SEM) confirmed the spheroidal morphology of ZrO₂ after inhibitor loading, while contact angle measurements showed improved hydrophobicity due to reduced porosity from the nanoparticles. Electrochemical impedance spectroscopy (EIS) showed enhanced corrosion resistance in the modified coatings compared to reference coatings, demonstrating stable impedance values and delayed electrolyte uptake. These findings suggest the potential of the developed coating system in mitigating carbon steel corrosion, offering insights for its application across various industries. Full article

Within this study, the influence of particles of different types, natures, and sizes on the mechanical and corrosion resistance of pigmented systems containing spherical zinc was studied. For this study, prominent representatives from the group of transition metal dichalcogenides (MoS₂, WS₂), layered transition metal oxides (MoO₃, WO₃), and other semiconductor materials (ZnS and ZnO) were used. The layered ultra-thin structure of these particles was predisposed to provide enhanced mechanical and anti-corrosion performance. The mechanical properties of the studied coatings were tested using standardized mechanical tests, while the anti-corrosion performance of these coatings was studied using standardized cyclic corrosion tests and the linear polarization electrochemical technique. The results of the experimental techniques bring completely original knowledge about the action of these pigments in paint systems pigmented with zinc. The results of experimental techniques have shown enhancement and an increase in both mechanical and anti-corrosion performance when using these special types of inorganic pigments. In particular, with organic coatings pigmented with MoO₃, there was an increase in mechanical resistance mainly due to its morphology and layered structure. In addition, a significant enhancement of the anti-corrosion efficiency was noted for this type of organic coating due to the enhancement of individual types of action mechanisms typical and proven for zinc-pigmented systems. These original findings can be used in the search for possibilities to reduce the zinc content in zinc-pigmented organic coatings. This partial replacement of zinc particles leads not only to a reduction in the zinc content in the system but also to a significant strengthening of the mechanical resistance and an increase in the corrosion efficiency of the system. Full article

The influence of polymer emulsion, pigment filler, and dispersant on the corrosion resistance of polymer cement-based composite anti-corrosion coatings were investigated in this study. Adhesion loss rate tests and electrochemical tests were conducted on samples. The research results show that optimal corrosion resistance can be achieved with a 45 wt% dosage of emulsion, a 6 wt% dosage of pigment filler, and a 0.30 wt% dosage of dispersant. The bonding properties of bare steel bars, epoxy-coated steel bars, and polymer cement-based composite anti-corrosion coated steel bars with grout were compared. The results show that the polymer cement-based composite anti-corrosion coating can enhance the bonding properties of the samples. Furthermore, the microscopic analysis was conducted on the samples. The results demonstrate that the appropriate addition of emulsion can fill internal pores of the coating, tightly bonding hydration products with unhydrated cement particles. Moreover, incorporating a suitable dosage of functional additives enhances the stability of the coating system and leads to a denser microstructure. Full article

Corrosion-related damage incurs significant capital costs in many industries. In this study, an anti-corrosive pigment was synthesized by modifying calcium carbonate with sodium alginate (SA), and smart self-healing coatings were synthesized by reinforcing the anti-corrosive pigments into a polyolefin matrix. Structural changes during the synthesis of the anti-corrosive pigment were examined using scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. Moreover, thermal gravimetric analysis confirmed the loading of the corrosion inhibitor, and electrochemical impedance spectroscopic analysis revealed a stable impedance value, confirming the improved corrosion resistance of the modified polyolefin coatings. The incorporation of the anticorrosive pigment into a polyolefin matrix resulted in improved pore resistance properties and capacitive behavior, indicating a good barrier property of the modified coatings. The formation of a protective film on the steel substrate reflected the adsorption of the corrosion inhibitor (SA) on the steel substrate, which further contributed to enhancing the corrosion resistance of the modified coatings. Moreover, the formation of the protective film was also analyzed by profilometry and elemental mapping analysis. Full article

This paper deals with the properties and testing of newly prepared organic pigments based on melamine cyanurate containing magnesium or zinc cations depending on their composition and anticorrosive properties in model coatings. Organic pigments based on melamine cyanurate with Mg²⁺ in the form of a complex differing in the ratio of melamine and cyanurate units were prepared. Furthermore, a pigment based on melamine citrate with magnesium cation Mg²⁺, a pigment based on melamine citrate with magnesium cation, and a pigment based on melamine cyanurate with zinc cation were prepared. The properties of Mg-containing organic pigments were also compared with those of selected magnesium-containing inorganic oxide-type pigments. The above-synthesized pigments were characterized by inductively coupled plasma-optical emission spectroscopy, elemental analysis, scanning electron microscopy, and X-ray diffraction. In addition, the basic parameters that are indicative of the applicability of the pigments in the binders of anti-corrosion coatings were determined. The anti-corrosive properties of the tested pigments were verified after application to the epoxy-ester resin-based paint binder in three different concentrations: at pigment volume concentrations of 0.10%, 0.25%, and 0.50%. The anticorrosive effectiveness of pigmented organic coatings was verified by cyclic corrosion tests in a salt electrolyte fog (NaCl + (NH₄)₂SO₄) in an atmosphere containing SO₂ and by the electrochemical technique of linear polarization. Finally, the effect of the structure of the pigments on the mechanical resistance of the organic coatings was investigated. The results obtained showed that the new organic pigments exhibit anticorrosive properties, and at the same time, differences in performance were found depending on the structure of the pigments tested. Specifically, the results of cyclic corrosion tests and the electrochemical technique of linear polarization clearly demonstrated that synthesized pigments of the organic type based on melamine cyanurate containing magnesium or zinc cations ensure the anti-corrosion efficiency of the tested organic coatings. The highest anti-corrosion efficiency was achieved by the system pigmented with synthesized melamine cyanurate with magnesium cation (C₁₂H₁₆MgN₁₈O₆), whose anti-corrosion efficiency was comparable to the anti-corrosion efficiency of the tested inorganic pigment MgFe₂O₄, which was prepared by high-temperature solid-phase synthesis. In addition, these organic coatings achieved high mechanical resistance after being tested using the most used standardized mechanical tests. Full article

This work addresses the possibilities of using synthesized novel magnesium complex dyes in zinc pigmented organic coatings based on epoxyester resin to reduce the zinc content in these coatings while maintaining or increasing the anticorrosive efficiency of them. The magnesium complexes Mg-Dye-I (C₃₄H₂₆MgN₈O₆), Mg-Dye-II (C₂₆H₁₉MgN₃O₅), Mg-Dye-III (C₁₇H₁₀MgN₂O₃), and Mg-Dye-IV (C₂₅H₁₈MgN₄O₆) with a series of azo carboxylate ligands were prepared from the diazo-coupling reaction of anthranilic acid with 5-methyl-2-phenyl-3-pyrazolone (Dye I; C₁₇H₁₄N₄O₃), anthranilic acid with naphthol AS-PH (Dye II; C₂₆H₂₁N₃O₅), anthranilic acid with 2-naphthol (Dye III; C₁₇H₁₂N₂O₃), and 2-amino-5-nitrophenol with naphthol AS-PH (Dye IV; C₂₅H₂₀N₄O₆). The synthesized novel magnesium complex dyes were characterized by analytical methods. Model coatings containing these dyes at pigment volume concentrations (PVCs) = 1, 3, 5 and 10% and zinc at a ratio of pigment volume concentration/critical pigment volume concentration (PVC/CPVC) = 0.60 were formulated to study the inhibitory properties of the individual synthesized magnesium complex dyes. Model coatings containing inorganic pigments (MgO and Ca-Mg-HPO₄) at PVCs = 1%, 3%, 5% and 10% and zinc at PVC/CPVC = 0.60 were also formulated. The coating pigmented only by zinc at PVC/CPVC = 0.60 was prepared as a standard organic coating. Corrosion resistance was also evaluated by potentiodynamic polarization studies and electrochemical impedance spectroscopy. The properties of organic coatings were also tested using other standardized and derived corrosion tests. In addition, the mechanical properties of the studied organic coatings were determined using standard tests. The aim of the work was to verify the possible synergistic efficiency of novel magnesium complex dyes by improving the mechanical, anti-corrosion, and chemical properties of zinc pigmented organic coatings. Full article

This research paper presents the fabrication of epoxy coatings along with the hybrid combination of SiO₂ and ZrO₂. The epoxy resin is incorporated with SiO₂ as the primary pigment and ZrO₂ as the synergist pigment. The study delves into the adhesion, barrier, and anti-corrosion properties of these coatings, enriched with silica and zirconium nanoparticles, and investigates their impact on the final properties of the epoxy coating. The epoxy resin, a Diglycidyl ether bisphenol-A (DGEBA) type, is cured with a polyamidoamine adduct-based curing agent. To evaluate the protective performance of silica SiO₂ and zirconia ZrO₂ nanoparticles in epoxy coatings, the coated samples were tested in a 3.5% NaCl solution. The experimental results clearly demonstrate a remarkable improvement in the ultimate tensile strength (UTS), yield strength (YS), and Elastic Modulus. In comparison to using SiO₂ separately, the incorporation of both ZrO₂ and SiO₂ resulted in a substantial increase of 43.5% in UTS, 74.2% in YS, and 8.2% in Elastic Modulus. The corrosion test results revealed that the combination of DGEBA, SiO₂, and ZrO₂ significantly enhanced the anti-corrosion efficiency of the organic coatings. Both these pigments exhibited superior anti-corrosion effects and mechanical properties compared to conventional epoxy coatings, leading to a substantial increase in the anti-corrosion efficiency of the developed coating. This research focuses the potential of SiO₂ and ZrO₂ in hybrid combination for applications, where mechanical, corrosion and higher adhesion to the substrates are of prime importance. Full article

The aim of the work was to investigate the prospects of imparting valuable physical and chemical properties, such as corrosion resistance, impact and bending strength, adhesion and storage stability, to hybrid systems of potassium and sodium silicates by modification with organic compounds. Here, we present the results of worldwide activities of scientific teams studying the manufacturing technology of modified liquid glass anticorrosive coatings used in chemical, petrochemical industry and modern construction. The authors theoretically and economically justified and put into practice novel organic and inorganic compositions with increased viability. The durable and waterproof coatings with good adhesion to various substrates (non-ferrous metals, steel, plastered surface and wood) were obtained. The authors demonstrate the possibility of recycling of zinc-containing rongalite production wastes and sludge pastes of electrochemical productions containing alkali and alkaline-earth metal cations by including them into the composition instead of pigmenting solid-phase components. We propose a technological route for obtaining anticorrosion coatings to protect aluminum and its alloys operated in a zone of elevated (up to 673 K) temperatures. Full article

Polymer-based coatings are a long-established category of protective coatings for metals and alloys regarding corrosion inhibition. The polymer films can degrade, and when coated on metallic substrates, the degradation facilitates moisture and oxygen penetration, reducing the polymer film’s adhesion to the metallic substrate and exposing the substrate to extreme conditions capable of corrosion. For this reason, pigments, inhibitors, and other compatible blends are added to the polymer coating formulations to enhance adhesion and protection. To prevent the possible deterioration of inhibitor-spiked polymer coatings, inhibitors are encapsulated through diverse techniques to avoid leakage and to provide a controlled release in response to the corrosion trigger. This review discusses polymer-based coating performance in corrosion-causing environments to protect metals, focusing more on commercial steels, a readily available construction-relevant material used in extensive applications. It further beams a searchlight on advances made on polymer-based coatings that employ metal–organic frameworks (MOFs) as functional additives. MOFs possess a tailorable structure of metal ions and organic linkers and have a large loading capacity, which is crucial for corrosion inhibitor delivery. Results from reviewed works show that polymer-based coatings provide barrier protection against the ingress of corrosive species and offer the chance to add several functions to coatings, further enhancing their anti-corrosion properties. Full article