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Mikhail L. Zheludkevich - One of the best experts on this subject based on the ideXlab platform.
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a novel bilayer system comprising ldh conversion layer and sol gel coating for active Corrosion Protection of aa2024
Corrosion Science, 2018Co-Authors: Kiryl Yasakau, Mikhail L. Zheludkevich, Silvar Kallip, João Tedim, M. G. S. Ferreira, A Kuznetsova, M StarykevichAbstract:Abstract In this work active Corrosion Protection of AA2024 by a bilayer system consisting of a LDH (layered double hydroxides) conversion layer coated by a sol-gel film was studied. Impedance and Scanning vibrating electrode technique (SVET) studies demonstrated an efficient active Corrosion Protection and self-healing abilities of the systems containing LDH layer loaded with vanadate Corrosion inhibitor. Microstructural and chemical analysis of the surface after Corrosion testing showed accumulation of chlorine signal in LDH coatings. The scavenging of chlorides and release of vanadate inhibitor from LDH can explain high efficiency of Corrosion inhibition of AA2024 by the novel protective system.
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Corrosion Protection of AA2024 by sol-gel coatings modified with MBT-loaded polyurea microcapsules
Chemical Engineering Journal, 2016Co-Authors: Frederico Maia, Kiryl Yasakau, T. Henriques, J. Carneiro, A. Cabral, Mikhail L. Zheludkevich, Silvar Kallip, José Venâncio, João Tedim, M. G. S. FerreiraAbstract:In this work we report the synthesis of polyurea microcapsules loaded with Corrosion inhibitor 2-mercaptobenzothiazole (MBT) for Corrosion Protection of 2024 aluminum alloy. The microcapsules were prepared by interfacial polycondensation. The resulting capsules exhibit spherical shape, with diameter ranging between 100. nm and 2. μm. The loading content of MBT was found to be 5 wt% and release studies showed that MBT is preferentially released under acidic and alkaline conditions and follows a Fickian diffusion model. This pH dependency seems suitable for Protection of metallic alloys where Corrosion processes are accompanied by local pH changes. Furthermore, the microcapsules were added to a hybrid sol-gel coating and its performance assessed by electrochemical and accelerated standard tests. The results obtained indicate that capsules loaded with MBT do not affect negatively the barrier properties of sol-gel coatings, and contribute for the enhancement of adhesion of coatings to the metallic substrate. More relevant, these additives impart active Corrosion Protection suppressing Corrosion activity at defect sites, which opens prospects for application of polyurea microcapsules as additives for high-performance coatings.
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“Smart” coatings for active Corrosion Protection based on multi-functional micro and nanocontainers
Electrochimica Acta, 2012Co-Authors: Mikhail L. Zheludkevich, João Tedim, Mário G.s. FerreiraAbstract:Abstract The application of organic coatings is the most common and cost effective method for Corrosion Protection and extension of service life of many metallic structures in corrosive environments. However, the degradation processes rapidly develop once the disruption of the protective barrier occurs. Therefore, an active Protection based on the “self-healing” of defects in coatings is necessary to attain a long-term effect. The present paper brings a brief summary of recent works in the area of new multi-level protective systems, based on the controlled release of antiCorrosion species from “smart” micro and nanocontainers incorporated into a polymer or hybrid coating matrix. Nanocontainer (or nanoreservoir) is a nanosized volume filled with an active substance confined in a porous core and/or a shell which precludes the direct contact between the active agent and the adjacent environment. Several types of nanoreservoirs of Corrosion inhibitors, nanotraps and microcapsules with water displacers have been recently developed, incorporated into coating systems and assessed in terms of active Corrosion Protection. A multi-level self-healing approach combining several damage prevention and restoration mechanisms within the same system, including the entrapment of corrosive ions, Corrosion inhibition and water displacement from active defects, is here reviewed.
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sol gel polyelectrolyte active Corrosion Protection system
Advanced Functional Materials, 2008Co-Authors: Sviatlana V. Lamaka, Mikhail L. Zheludkevich, Dmitry G. Shchukin, Daria V. Andreeva, Helmuth Möhwald, M. G. S. FerreiraAbstract:This work presents a new type of feed-back active coating with inhibitor-containing reservoirs for Corrosion Protection of metallic substrates. The reservoirs are composed of stratified layers of oppositely charged polyelectrolytes deposited on AA2024 aluminum alloy coated with hybrid sol-gel film. The layer-by-layer assembled polyelectrolyte film with the entrapped Corrosion inhibitor is constructed by sequential spray-coating deposition of water solutions of poly(ethyleneimine), poly(sodium styrenesulfonate) and 8-hydroxyquiniline on the top of the sol-gel coating. The active Corrosion Protection of AA2024 alloy coated with SiO2/ZrO2 sol-gel film and modified by polyelectrolytes is demonstrated by electrochemical impedance spectroscopy and scanning vibrating electrode technique. The results obtained here show that polyelectrolyte films deposited atop of the hybrid sol-gel coating on AA2024 alloy remarkably improve the long-term Protection performance providing additional “intelligent” antiCorrosion effect that results from delivery of inhibiting species “on demand”. This becomes possible since the configuration of the polyelectrolyte molecules depends on the presence of H+ ions making the polyelectrolyte film sensitive to the pH of the surrounding solution. The source of local pH changes is the Corrosion process starting in the micro- and nano-defects leading to increased permeability of the polyelectrolyte reservoir and, consequently, to controllable release of entrapped inhibitor.
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Influence of inhibitor addition on the Corrosion Protection performance of sol-gel coatings on AA2024
Progress in Organic Coatings, 2008Co-Authors: Kiryl Yasakau, O. V. Karavai, Mikhail L. Zheludkevich, M. G. S. FerreiraAbstract:Sol-gel films are actively investigated during the last decade as possible candidates for environmentally friendly pre-treatments. However, the important drawback in this case is the lack of active Corrosion Protection and self-healing ability. In this work a certain number of Corrosion inhibitors for AA2024 was used as additives to the hybrid sol-gel formulations in order to confer active Corrosion Protection without damaging the coating. The 8-hydroxyquinoline, benzotriazole and cerium nitrate were added at different stages of the synthesis process to understand the role of possible interaction of the inhibitor with components of the sol-gel system. The Scanning Vibrating Electrode Technique and Electrochemical Impedance Spectroscopy were employed as two main techniques to characterize the Corrosion Protection performance of the hybrid sol-gel films doped with inhibitors and to understand the mechanisms of Corrosion Protection. The results demonstrate that 8-hydroxyquinoline and cerium nitrate do not affect the stability of sol-gel films and confer additional active Corrosion Protection effect. In contrast to this, benzotriazole leads to deterioration of the Corrosion Protection properties of hybrid sol-gel films. © 2008.
M. G. S. Ferreira - One of the best experts on this subject based on the ideXlab platform.
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a novel bilayer system comprising ldh conversion layer and sol gel coating for active Corrosion Protection of aa2024
Corrosion Science, 2018Co-Authors: Kiryl Yasakau, Mikhail L. Zheludkevich, Silvar Kallip, João Tedim, M. G. S. Ferreira, A Kuznetsova, M StarykevichAbstract:Abstract In this work active Corrosion Protection of AA2024 by a bilayer system consisting of a LDH (layered double hydroxides) conversion layer coated by a sol-gel film was studied. Impedance and Scanning vibrating electrode technique (SVET) studies demonstrated an efficient active Corrosion Protection and self-healing abilities of the systems containing LDH layer loaded with vanadate Corrosion inhibitor. Microstructural and chemical analysis of the surface after Corrosion testing showed accumulation of chlorine signal in LDH coatings. The scavenging of chlorides and release of vanadate inhibitor from LDH can explain high efficiency of Corrosion inhibition of AA2024 by the novel protective system.
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Corrosion Protection of AA2024 by sol-gel coatings modified with MBT-loaded polyurea microcapsules
Chemical Engineering Journal, 2016Co-Authors: Frederico Maia, Kiryl Yasakau, T. Henriques, J. Carneiro, A. Cabral, Mikhail L. Zheludkevich, Silvar Kallip, José Venâncio, João Tedim, M. G. S. FerreiraAbstract:In this work we report the synthesis of polyurea microcapsules loaded with Corrosion inhibitor 2-mercaptobenzothiazole (MBT) for Corrosion Protection of 2024 aluminum alloy. The microcapsules were prepared by interfacial polycondensation. The resulting capsules exhibit spherical shape, with diameter ranging between 100. nm and 2. μm. The loading content of MBT was found to be 5 wt% and release studies showed that MBT is preferentially released under acidic and alkaline conditions and follows a Fickian diffusion model. This pH dependency seems suitable for Protection of metallic alloys where Corrosion processes are accompanied by local pH changes. Furthermore, the microcapsules were added to a hybrid sol-gel coating and its performance assessed by electrochemical and accelerated standard tests. The results obtained indicate that capsules loaded with MBT do not affect negatively the barrier properties of sol-gel coatings, and contribute for the enhancement of adhesion of coatings to the metallic substrate. More relevant, these additives impart active Corrosion Protection suppressing Corrosion activity at defect sites, which opens prospects for application of polyurea microcapsules as additives for high-performance coatings.
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hybrid epoxy silane coatings for improved Corrosion Protection of mg alloy
Corrosion Science, 2013Co-Authors: Fabiola Brusciotti, Sviatlana V. Lamaka, Darya Snihirova, H B Xue, Fatima M Montemor, M. G. S. FerreiraAbstract:Abstract New hybrid epoxy–silane coatings, with added functionalities for improved performance and durability, were designed to increase the Corrosion Protection of magnesium alloys. The Corrosion behavior of the coated AZ31 was studied through electrochemical impedance spectroscopy (EIS) in 0.05 M NaCl. The morphology and surface chemistry of the samples were also investigated through scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR) before and after immersion in the electrolyte. The new hybrid silane coatings showed a high resistance to Corrosion that persisted throughout one-month immersion in a pH-neutral NaCl solution.
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sol gel polyelectrolyte active Corrosion Protection system
Advanced Functional Materials, 2008Co-Authors: Sviatlana V. Lamaka, Mikhail L. Zheludkevich, Dmitry G. Shchukin, Daria V. Andreeva, Helmuth Möhwald, M. G. S. FerreiraAbstract:This work presents a new type of feed-back active coating with inhibitor-containing reservoirs for Corrosion Protection of metallic substrates. The reservoirs are composed of stratified layers of oppositely charged polyelectrolytes deposited on AA2024 aluminum alloy coated with hybrid sol-gel film. The layer-by-layer assembled polyelectrolyte film with the entrapped Corrosion inhibitor is constructed by sequential spray-coating deposition of water solutions of poly(ethyleneimine), poly(sodium styrenesulfonate) and 8-hydroxyquiniline on the top of the sol-gel coating. The active Corrosion Protection of AA2024 alloy coated with SiO2/ZrO2 sol-gel film and modified by polyelectrolytes is demonstrated by electrochemical impedance spectroscopy and scanning vibrating electrode technique. The results obtained here show that polyelectrolyte films deposited atop of the hybrid sol-gel coating on AA2024 alloy remarkably improve the long-term Protection performance providing additional “intelligent” antiCorrosion effect that results from delivery of inhibiting species “on demand”. This becomes possible since the configuration of the polyelectrolyte molecules depends on the presence of H+ ions making the polyelectrolyte film sensitive to the pH of the surrounding solution. The source of local pH changes is the Corrosion process starting in the micro- and nano-defects leading to increased permeability of the polyelectrolyte reservoir and, consequently, to controllable release of entrapped inhibitor.
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Influence of inhibitor addition on the Corrosion Protection performance of sol-gel coatings on AA2024
Progress in Organic Coatings, 2008Co-Authors: Kiryl Yasakau, O. V. Karavai, Mikhail L. Zheludkevich, M. G. S. FerreiraAbstract:Sol-gel films are actively investigated during the last decade as possible candidates for environmentally friendly pre-treatments. However, the important drawback in this case is the lack of active Corrosion Protection and self-healing ability. In this work a certain number of Corrosion inhibitors for AA2024 was used as additives to the hybrid sol-gel formulations in order to confer active Corrosion Protection without damaging the coating. The 8-hydroxyquinoline, benzotriazole and cerium nitrate were added at different stages of the synthesis process to understand the role of possible interaction of the inhibitor with components of the sol-gel system. The Scanning Vibrating Electrode Technique and Electrochemical Impedance Spectroscopy were employed as two main techniques to characterize the Corrosion Protection performance of the hybrid sol-gel films doped with inhibitors and to understand the mechanisms of Corrosion Protection. The results demonstrate that 8-hydroxyquinoline and cerium nitrate do not affect the stability of sol-gel films and confer additional active Corrosion Protection effect. In contrast to this, benzotriazole leads to deterioration of the Corrosion Protection properties of hybrid sol-gel films. © 2008.
Dmitry G. Shchukin - One of the best experts on this subject based on the ideXlab platform.
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Comparative study of the effect of halloysite nanocontainers on autonomic Corrosion Protection of polyepoxy coatings on steel by salt-spray tests
Progress in Organic Coatings, 2017Co-Authors: Elena Shchukina, Dmitry Grigoriev, T. V. Sviridova, Dmitry G. ShchukinAbstract:Abstract The comparative study was carried out to show the effect of the halloysite nanotubes loaded with three inhibitors with different properties (Korantin SMK, Halox 520 and (NH4)2TiF6) as an additive for autonomic Corrosion Protection of polyepoxy coating on steel substrate. The comparison was carried out employing neutral salt-spray test (5% NaCl, 35 °C, different time). Commercial polyepoxy coating containing 20 wt% of zinc phosphate was used as a benchmark during testing. We demonstrated that inhibitor-loaded halloysites at 5 wt% concentration are able to successfully substitute 20 wt% zinc phosphate in the commercial polyepoxy coating even improving its Corrosion Protection performance, which depends in a large extend on the release profiles of the inhibitors loaded into halloysite nanotubes. On the contrary, addition of the free inhibitors into the coating showed complete deterioration of the Corrosion Protection properties for all inhibitors.
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Mesoporous silica nanoparticles for active Corrosion Protection
ACS nano, 2011Co-Authors: Dimitriya Borisova, Helmuth Möhwald, Dmitry G. ShchukinAbstract:This work presents the synthesis of monodisperse, mesoporous silica nanoparticles and their application as nanocontainers loaded with Corrosion inhibitor (1H-benzotriazole (BTA)) and embedded in hybrid SiOx/ZrOx sol−gel coating for the Corrosion Protection of aluminum alloy. The developed porous system of mechanically stable silica nanoparticles exhibits high surface area (∼1000 m2·g−1), narrow pore size distribution (d ∼ 3 nm), and large pore volume (∼1 mL·g−1). As a result, a sufficiently high uptake and storage of the Corrosion inhibitor in the mesoporous nanocontainers was achieved. The successful embedding and homogeneous distribution of the BTA-loaded monodisperse silica nanocontainers in the passive anticorrosive SiOx/ZrOx film improve the wet Corrosion resistance of the aluminum alloy AA2024 in 0.1 M sodium chloride solution. The enhanced Corrosion Protection of this newly developed active system in comparison to the passive sol−gel coating was observed during a simulated Corrosion process by the ...
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layer by layer polyelectrolyte inhibitor nanostructures for metal Corrosion Protection
ACS Applied Materials & Interfaces, 2010Co-Authors: Daria V. Andreeva, Ekaterina V Skorb, Dmitry G. ShchukinAbstract:Multicomponent coating formed by polyelectrolyte multilayers opens new opportunities for antiCorrosion Protection. Here we demonstrate a novel method of Corrosion Protection based on formation and deposition of polyelectrolyte multilayers on aluminum and steel alloys, analysis of different polyelectrolyte compositions (strong−strong, strong−weak, weak−weak) as candidates for Corrosion protective layers. The multilayer nanonetwork exhibits very high Corrosion Protection because of the nature and versatility of the polyelectrolyte complex. The antiCorrosion activity of the coating is based on the following mechanisms: (1) pH buffer formed by polybase and polyacid complex suppress pH changes caused by Corrosion degradation; (2) coating regeneration and defect elimination due to relative mobility of polymer chains in swollen state; (3) polyelectrolyte layers form a carrier for inhibitor allowing its release on demand; (4) polyelectrolyte nanonetwork provides a barrier between surface and environment. We optim...
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surface modified mesoporous sio2 containers for Corrosion Protection
Advanced Functional Materials, 2009Co-Authors: Ekaterina V Skorb, Helmuth Möhwald, Daria V. Andreeva, Dmitri Fix, Dmitry G. ShchukinAbstract:The development of active Corrosion Protection systems for metallic substrates is an issue of prime importance for many industrial applications. The present work shows a new contribution to the design of a new protective system based on surface modified mesoporous silica containers. Incorporation of silica-based containers into special sol–gel matrix allows for a self-healing effect to be achieved during the Corrosion process. The self-healing ability occurs due to release of entrapped Corrosion inhibitors in response to pH changes caused by the Corrosion process. A silica–zirconia-based hybrid film is used in this work as a coating matrix deposited on AA2024 aluminum alloy. Mesoporous silica nano-particles are covered layer-by-layer with polyelectrolyte layers and loaded with inhibitor [2-(benzothiazol-2-ylsulfanyl)-succinic acid]. The hybrid film with nanocontainers reveals enhanced long-term Corrosion Protection in comparison with the individual sol–gel films. The scanning vibrating electrode technique also shows an effective healing ability of containers to cure the Corrosion defects. This effect is due to the release of the Corrosion inhibitor triggered by the Corrosion processes started in the cavities. The approach described herein can be used in many applications where active Corrosion Protection of materials is required.
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sol gel polyelectrolyte active Corrosion Protection system
Advanced Functional Materials, 2008Co-Authors: Sviatlana V. Lamaka, Mikhail L. Zheludkevich, Dmitry G. Shchukin, Daria V. Andreeva, Helmuth Möhwald, M. G. S. FerreiraAbstract:This work presents a new type of feed-back active coating with inhibitor-containing reservoirs for Corrosion Protection of metallic substrates. The reservoirs are composed of stratified layers of oppositely charged polyelectrolytes deposited on AA2024 aluminum alloy coated with hybrid sol-gel film. The layer-by-layer assembled polyelectrolyte film with the entrapped Corrosion inhibitor is constructed by sequential spray-coating deposition of water solutions of poly(ethyleneimine), poly(sodium styrenesulfonate) and 8-hydroxyquiniline on the top of the sol-gel coating. The active Corrosion Protection of AA2024 alloy coated with SiO2/ZrO2 sol-gel film and modified by polyelectrolytes is demonstrated by electrochemical impedance spectroscopy and scanning vibrating electrode technique. The results obtained here show that polyelectrolyte films deposited atop of the hybrid sol-gel coating on AA2024 alloy remarkably improve the long-term Protection performance providing additional “intelligent” antiCorrosion effect that results from delivery of inhibiting species “on demand”. This becomes possible since the configuration of the polyelectrolyte molecules depends on the presence of H+ ions making the polyelectrolyte film sensitive to the pH of the surrounding solution. The source of local pH changes is the Corrosion process starting in the micro- and nano-defects leading to increased permeability of the polyelectrolyte reservoir and, consequently, to controllable release of entrapped inhibitor.
Per M Claesson - One of the best experts on this subject based on the ideXlab platform.
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heating induced enhancement of Corrosion Protection of carbon steel by a nanocomposite film containing mussel adhesive protein
Journal of The Electrochemical Society, 2017Co-Authors: Per M Claesson, Chengdong Chen, Fan Zhang, Ruiqing Hou, Shigang Dong, C J Lin, Jinshan PanAbstract:Application of protective coatings on metals may involve a thermal treatment process. In this study, the effect of thermal treatment up to 200 degrees C on the Corrosion Protection was investigated ...
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Corrosion Protection by hydrophobic silica particle polydimethylsiloxane composite coatings
Corrosion Science, 2015Co-Authors: Jinshan Pan, Per M Claesson, Lina Ejenstam, Agne SwerinAbstract:In this study, the time-dependent Corrosion Protection ability of 10–15 µm thin polydimethylsiloxane -nanoparticle composite coatings was evaluated using mainly open circuit potential and electroch ...
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influence of polyaniline and ceria nanoparticle additives on Corrosion Protection of a uv cure coating on carbon steel
Corrosion Science, 2014Co-Authors: Majid Sababi, Jinshan Pan, Pererik Augustsson, Pererik Sundell, Per M ClaessonAbstract:Influence of a few percents additives of polyaniline doped with phosphoric acid (PAni-PA) and ceria nanoparticle on Corrosion Protection of a new ultraviolet (UV)-cure polyester acrylate coating have been studied for coil coating on carbon steel by electrochemical measurements during exposure to a NaCl solution. The results demonstrate that the presence of ceria nanoparticles improves the barrier property and stability of the coating. Adding the PAni-PA results in active Corrosion Protection for carbon steel due to passivation of the steel, and the combination of both additives greatly enhances the Protection property over that of the coating matrix alone.
Mário G.s. Ferreira - One of the best experts on this subject based on the ideXlab platform.
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“Smart” coatings for active Corrosion Protection based on multi-functional micro and nanocontainers
Electrochimica Acta, 2012Co-Authors: Mikhail L. Zheludkevich, João Tedim, Mário G.s. FerreiraAbstract:Abstract The application of organic coatings is the most common and cost effective method for Corrosion Protection and extension of service life of many metallic structures in corrosive environments. However, the degradation processes rapidly develop once the disruption of the protective barrier occurs. Therefore, an active Protection based on the “self-healing” of defects in coatings is necessary to attain a long-term effect. The present paper brings a brief summary of recent works in the area of new multi-level protective systems, based on the controlled release of antiCorrosion species from “smart” micro and nanocontainers incorporated into a polymer or hybrid coating matrix. Nanocontainer (or nanoreservoir) is a nanosized volume filled with an active substance confined in a porous core and/or a shell which precludes the direct contact between the active agent and the adjacent environment. Several types of nanoreservoirs of Corrosion inhibitors, nanotraps and microcapsules with water displacers have been recently developed, incorporated into coating systems and assessed in terms of active Corrosion Protection. A multi-level self-healing approach combining several damage prevention and restoration mechanisms within the same system, including the entrapment of corrosive ions, Corrosion inhibition and water displacement from active defects, is here reviewed.
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Novel hybrid sol-gel coatings for Corrosion Protection of AZ31B magnesium alloy
Electrochimica Acta, 2008Co-Authors: Sviatlana V. Lamaka, Mikhail L. Zheludkevich, Maria De Fátima Montemor, Alexandre Ferreira Galio, C. Trindade, Luis Frederico Pinheiro Dick, Mário G.s. FerreiraAbstract:Abstract This work aims to develop and study new antiCorrosion films for AZ31B magnesium alloy based on the sol–gel coating approach. Hybrid organic–inorganic sols were synthesized by copolymerization of epoxy-siloxane and titanium or zirconium alkoxides. Tris(trimethylsilyl) phosphate was also used as additive to confer additional Corrosion Protection to magnesium-based alloy. A sol–gel coating, about 5-μm thick, shows good adhesion to the metal substrate and prevents Corrosion attack in 0.005 M NaCl solution for 2 weeks. The sol–gel coating system doped with tris(trimethylsilyl)-phosphate revealed improved Corrosion Protection of the magnesium alloy due to formation of hydrolytically stable Mg–O–P chemical bonds. The structure and the thickness of the sol–gel film were characterized by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The Corrosion behaviour of AZ31B substrates pre-treated with the sol–gel derived hybrid coatings was tested by electrochemical impedance spectroscopy (EIS). The chemical composition of the silylphosphate-containing sol–gel film at different depths was investigated by X-ray photoelectron spectroscopy (XPS) with depth profiling.
