The Experts below are selected from a list of 20226 Experts worldwide ranked by ideXlab platform
Mikhail L. Zheludkevich - One of the best experts on this subject based on the ideXlab platform.
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Chitosan-based self-healing Protective Coatings doped with cerium nitrate for corrosion protection of aluminum alloy 2024
Progress in Organic Coatings, 2012Co-Authors: J. Carneiro, A. J. D. Silvestre, Susana C M Fernandes, Carmen S.r. Freire, João Tedim, M. G. S. Ferreira, Alessandro Gandini, Mikhail L. ZheludkevichAbstract:The good film forming ability, specific solubility and versatile chemical functionalization of chitosan make it a promising candidate for “green” Protective Coatings. In the present work, these features are exploited together with chitosan high complexing ability to obtain inhibitor-containing anticorrosion Coatings for active protection of aluminum alloys. The functionalization of chitosan with fluorinated substituents was also evaluated as a possible route to improve barrier and surface properties of the coating matrix. It was observed that the chitosan layer worked as a reservoir for cationic Ce3+ corrosion inhibitor due to the complexation of Ce3+ with chitosan amino groups, which prevents its uncontrollable and fast leaching. These Ce-containing Coatings were found to confer active corrosion protection toward aluminum alloy 2024 as shown by electrochemical impedance spectroscopy. Moreover, the corrosion tests evidence the self-healing ability of prepared chitosan-based “green” Protective Coatings. The interaction between Ce3+ and chitosan and the concentration effect of the former on the performance of the latter from a corrosion standpoint is also discussed.
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zn al layered double hydroxides as chloride nanotraps in active Protective Coatings
Corrosion Science, 2012Co-Authors: João Tedim, Mikhail L. Zheludkevich, A Kuznetsova, A N Salak, Fatima Montemor, Darya Snihirova, M Pilz, M. G. S. FerreiraAbstract:Zn–Al layered double hydroxides (LDHs) intercalated with nitrate anions are suggested as chloride nanotraps for organic polymeric Coatings. The addition of such nanotraps to a polymer layer drastically reduces the permeability of corrosive chloride anions through the Protective Coatings. In solution, Zn(2)–Al–NO3 LDHs are responsive to the concentration of chlorides and the release of nitrates is accompanied by entrapment of chlorides, with the process governed by ion-exchange equilibrium. In particular, a coating modified with LDH–NO3 was found to exhibit significantly lower permeability to chlorides when compared to both unmodified and LDH–Cl-containing Coatings, which proves the applicability of LDHs in delaying coating degradation and corrosion initiation.
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evaluation of self healing ability in Protective Coatings modified with combinations of layered double hydroxides and cerium molibdate nanocontainers filled with corrosion inhibitors
Electrochimica Acta, 2012Co-Authors: M F Montemor, João Tedim, A Kuznetsova, Darya Snihirova, Maryna G Taryba, Sviatlana V Lamaka, Ioannis A Kartsonakis, A C Balaskas, G Kordas, Mikhail L. ZheludkevichAbstract:a b s t r a c t Nowadays, there is a strong demand on the search of thinner, but more effective organic Coatings for corrosion protection of metallic substrates, like galvanised steel, used in the automotive industry. In order to guarantee effective corrosion protection of these Coatings, and because chromate-based pigments cannot be used, one of the most attractive strategies consists on the modification of the organic matrix with nano-additives filled with corrosion inhibitors, which can be released to the active sites. In this work, two different nano-additives are explored as potential self-healing materials for the development of active Protective Coatings. These additives are layered double hydroxides and cerium molybdate hollow nanospheres loaded with mercaptobenzothiazole, as a corrosion inhibitor. These additives were added to epoxy primers, individually, or combining the two nanoadditives in the same layer. The electrochemical behaviour and the potential of self-healing ability were studied by electrochemical impedance spectroscopy, scanning vibrating electrode technique and scanning ion-selective electrode technique. The results reveal that both types of nanocontainers can provide effective corrosion inhibition on artificial induced defects, at different stages of the degradation process. Moreover, the results also show that there is a synergistic effect concerning corrosion inhibition and self-healing potential when a mixture of the two nanocontainers is used. The mechanism of self healing is presented and discussed in terms of effect of organic inhibitor and role of the nanocontainers, including effect of cerium ions released from cerium molibdate nanoparticles.
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Chitosan-based self-healing Protective Coatings doped with cerium nitrate for corrosion protection of aluminum alloy 2024
Progress in Organic Coatings, 2012Co-Authors: J. Carneiro, A. J. D. Silvestre, Susana C M Fernandes, Carmen S.r. Freire, João Tedim, M. G. S. Ferreira, Alessandro Gandini, Mikhail L. ZheludkevichAbstract:The good film forming ability, specific solubility and versatile chemical functionalization of chitosan make it a promising candidate for "green" Protective Coatings. In the present work, these features are exploited together with chitosan high complexing ability to obtain inhibitor-containing anticorrosion Coatings for active protection of aluminum alloys. The functionalization of chitosan with fluorinated substituents was also evaluated as a possible route to improve barrier and surface properties of the coating matrix. It was observed that the chitosan layer worked as a reservoir for cationic Ce 3+ corrosion inhibitor due to the complexation of Ce 3+ with chitosan amino groups, which prevents its uncontrollable and fast leaching. These Ce-containing Coatings were found to confer active corrosion protection toward aluminum alloy 2024 as shown by electrochemical impedance spectroscopy. Moreover, the corrosion tests evidence the self-healing ability of prepared chitosan-based "green" Protective Coatings. The interaction between Ce 3+ and chitosan and the concentration effect of the former on the performance of the latter from a corrosion standpoint is also discussed. © 2012 Elsevier B.V. All rights reserved.
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On the application of electrochemical impedance spectroscopy to study the self-healing properties of Protective Coatings
Electrochemistry Communications, 2007Co-Authors: Mikhail L. Zheludkevich, Kiryl Yasakau, Alexandre C. Bastos, O.v. KaravaiAbstract:Active corrosion protection based on self-healing of defects in Coatings is a vital issue for development of new advanced corrosion protection systems. However, there is a significant lack of experimental protocols, which can be routinely used to reveal the self-healing ability and to study the active corrosion protection properties of organic and hybrid Coatings. The present work demonstrates the possibility to use EIS (electrochemical impedance spectroscopy) for investigation of the self-healing properties of Protective Coatings applied on a metal surface. The model EIS experiments supported by SVET (scanning vibrating electrode technique) measurements show that an increase of low frequency impedance during immersion in the corrosive medium is related to the suppression of active corrosion processes and healing of the corroded areas. Thus, EIS can effectively be employed as a routine method to study the self-repair properties of different Protective systems. The 2024 aluminium alloy coated with hybrid sol– gel film was used as a model system to study the healing of artificial defects by an organic inhibitor (8-hydroxyquinoline). 2007 Elsevier B.V. All rights reserved.
João Tedim - One of the best experts on this subject based on the ideXlab platform.
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Chitosan-based self-healing Protective Coatings doped with cerium nitrate for corrosion protection of aluminum alloy 2024
Progress in Organic Coatings, 2012Co-Authors: J. Carneiro, A. J. D. Silvestre, Susana C M Fernandes, Carmen S.r. Freire, João Tedim, M. G. S. Ferreira, Alessandro Gandini, Mikhail L. ZheludkevichAbstract:The good film forming ability, specific solubility and versatile chemical functionalization of chitosan make it a promising candidate for “green” Protective Coatings. In the present work, these features are exploited together with chitosan high complexing ability to obtain inhibitor-containing anticorrosion Coatings for active protection of aluminum alloys. The functionalization of chitosan with fluorinated substituents was also evaluated as a possible route to improve barrier and surface properties of the coating matrix. It was observed that the chitosan layer worked as a reservoir for cationic Ce3+ corrosion inhibitor due to the complexation of Ce3+ with chitosan amino groups, which prevents its uncontrollable and fast leaching. These Ce-containing Coatings were found to confer active corrosion protection toward aluminum alloy 2024 as shown by electrochemical impedance spectroscopy. Moreover, the corrosion tests evidence the self-healing ability of prepared chitosan-based “green” Protective Coatings. The interaction between Ce3+ and chitosan and the concentration effect of the former on the performance of the latter from a corrosion standpoint is also discussed.
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zn al layered double hydroxides as chloride nanotraps in active Protective Coatings
Corrosion Science, 2012Co-Authors: João Tedim, Mikhail L. Zheludkevich, A Kuznetsova, A N Salak, Fatima Montemor, Darya Snihirova, M Pilz, M. G. S. FerreiraAbstract:Zn–Al layered double hydroxides (LDHs) intercalated with nitrate anions are suggested as chloride nanotraps for organic polymeric Coatings. The addition of such nanotraps to a polymer layer drastically reduces the permeability of corrosive chloride anions through the Protective Coatings. In solution, Zn(2)–Al–NO3 LDHs are responsive to the concentration of chlorides and the release of nitrates is accompanied by entrapment of chlorides, with the process governed by ion-exchange equilibrium. In particular, a coating modified with LDH–NO3 was found to exhibit significantly lower permeability to chlorides when compared to both unmodified and LDH–Cl-containing Coatings, which proves the applicability of LDHs in delaying coating degradation and corrosion initiation.
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evaluation of self healing ability in Protective Coatings modified with combinations of layered double hydroxides and cerium molibdate nanocontainers filled with corrosion inhibitors
Electrochimica Acta, 2012Co-Authors: M F Montemor, João Tedim, A Kuznetsova, Darya Snihirova, Maryna G Taryba, Sviatlana V Lamaka, Ioannis A Kartsonakis, A C Balaskas, G Kordas, Mikhail L. ZheludkevichAbstract:a b s t r a c t Nowadays, there is a strong demand on the search of thinner, but more effective organic Coatings for corrosion protection of metallic substrates, like galvanised steel, used in the automotive industry. In order to guarantee effective corrosion protection of these Coatings, and because chromate-based pigments cannot be used, one of the most attractive strategies consists on the modification of the organic matrix with nano-additives filled with corrosion inhibitors, which can be released to the active sites. In this work, two different nano-additives are explored as potential self-healing materials for the development of active Protective Coatings. These additives are layered double hydroxides and cerium molybdate hollow nanospheres loaded with mercaptobenzothiazole, as a corrosion inhibitor. These additives were added to epoxy primers, individually, or combining the two nanoadditives in the same layer. The electrochemical behaviour and the potential of self-healing ability were studied by electrochemical impedance spectroscopy, scanning vibrating electrode technique and scanning ion-selective electrode technique. The results reveal that both types of nanocontainers can provide effective corrosion inhibition on artificial induced defects, at different stages of the degradation process. Moreover, the results also show that there is a synergistic effect concerning corrosion inhibition and self-healing potential when a mixture of the two nanocontainers is used. The mechanism of self healing is presented and discussed in terms of effect of organic inhibitor and role of the nanocontainers, including effect of cerium ions released from cerium molibdate nanoparticles.
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Chitosan-based self-healing Protective Coatings doped with cerium nitrate for corrosion protection of aluminum alloy 2024
Progress in Organic Coatings, 2012Co-Authors: J. Carneiro, A. J. D. Silvestre, Susana C M Fernandes, Carmen S.r. Freire, João Tedim, M. G. S. Ferreira, Alessandro Gandini, Mikhail L. ZheludkevichAbstract:The good film forming ability, specific solubility and versatile chemical functionalization of chitosan make it a promising candidate for "green" Protective Coatings. In the present work, these features are exploited together with chitosan high complexing ability to obtain inhibitor-containing anticorrosion Coatings for active protection of aluminum alloys. The functionalization of chitosan with fluorinated substituents was also evaluated as a possible route to improve barrier and surface properties of the coating matrix. It was observed that the chitosan layer worked as a reservoir for cationic Ce 3+ corrosion inhibitor due to the complexation of Ce 3+ with chitosan amino groups, which prevents its uncontrollable and fast leaching. These Ce-containing Coatings were found to confer active corrosion protection toward aluminum alloy 2024 as shown by electrochemical impedance spectroscopy. Moreover, the corrosion tests evidence the self-healing ability of prepared chitosan-based "green" Protective Coatings. The interaction between Ce 3+ and chitosan and the concentration effect of the former on the performance of the latter from a corrosion standpoint is also discussed. © 2012 Elsevier B.V. All rights reserved.
M. G. S. Ferreira - One of the best experts on this subject based on the ideXlab platform.
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Chitosan-based self-healing Protective Coatings doped with cerium nitrate for corrosion protection of aluminum alloy 2024
Progress in Organic Coatings, 2012Co-Authors: J. Carneiro, A. J. D. Silvestre, Susana C M Fernandes, Carmen S.r. Freire, João Tedim, M. G. S. Ferreira, Alessandro Gandini, Mikhail L. ZheludkevichAbstract:The good film forming ability, specific solubility and versatile chemical functionalization of chitosan make it a promising candidate for “green” Protective Coatings. In the present work, these features are exploited together with chitosan high complexing ability to obtain inhibitor-containing anticorrosion Coatings for active protection of aluminum alloys. The functionalization of chitosan with fluorinated substituents was also evaluated as a possible route to improve barrier and surface properties of the coating matrix. It was observed that the chitosan layer worked as a reservoir for cationic Ce3+ corrosion inhibitor due to the complexation of Ce3+ with chitosan amino groups, which prevents its uncontrollable and fast leaching. These Ce-containing Coatings were found to confer active corrosion protection toward aluminum alloy 2024 as shown by electrochemical impedance spectroscopy. Moreover, the corrosion tests evidence the self-healing ability of prepared chitosan-based “green” Protective Coatings. The interaction between Ce3+ and chitosan and the concentration effect of the former on the performance of the latter from a corrosion standpoint is also discussed.
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zn al layered double hydroxides as chloride nanotraps in active Protective Coatings
Corrosion Science, 2012Co-Authors: João Tedim, Mikhail L. Zheludkevich, A Kuznetsova, A N Salak, Fatima Montemor, Darya Snihirova, M Pilz, M. G. S. FerreiraAbstract:Zn–Al layered double hydroxides (LDHs) intercalated with nitrate anions are suggested as chloride nanotraps for organic polymeric Coatings. The addition of such nanotraps to a polymer layer drastically reduces the permeability of corrosive chloride anions through the Protective Coatings. In solution, Zn(2)–Al–NO3 LDHs are responsive to the concentration of chlorides and the release of nitrates is accompanied by entrapment of chlorides, with the process governed by ion-exchange equilibrium. In particular, a coating modified with LDH–NO3 was found to exhibit significantly lower permeability to chlorides when compared to both unmodified and LDH–Cl-containing Coatings, which proves the applicability of LDHs in delaying coating degradation and corrosion initiation.
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Chitosan-based self-healing Protective Coatings doped with cerium nitrate for corrosion protection of aluminum alloy 2024
Progress in Organic Coatings, 2012Co-Authors: J. Carneiro, A. J. D. Silvestre, Susana C M Fernandes, Carmen S.r. Freire, João Tedim, M. G. S. Ferreira, Alessandro Gandini, Mikhail L. ZheludkevichAbstract:The good film forming ability, specific solubility and versatile chemical functionalization of chitosan make it a promising candidate for "green" Protective Coatings. In the present work, these features are exploited together with chitosan high complexing ability to obtain inhibitor-containing anticorrosion Coatings for active protection of aluminum alloys. The functionalization of chitosan with fluorinated substituents was also evaluated as a possible route to improve barrier and surface properties of the coating matrix. It was observed that the chitosan layer worked as a reservoir for cationic Ce 3+ corrosion inhibitor due to the complexation of Ce 3+ with chitosan amino groups, which prevents its uncontrollable and fast leaching. These Ce-containing Coatings were found to confer active corrosion protection toward aluminum alloy 2024 as shown by electrochemical impedance spectroscopy. Moreover, the corrosion tests evidence the self-healing ability of prepared chitosan-based "green" Protective Coatings. The interaction between Ce 3+ and chitosan and the concentration effect of the former on the performance of the latter from a corrosion standpoint is also discussed. © 2012 Elsevier B.V. All rights reserved.
J. Carneiro - One of the best experts on this subject based on the ideXlab platform.
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Chitosan-based self-healing Protective Coatings doped with cerium nitrate for corrosion protection of aluminum alloy 2024
Progress in Organic Coatings, 2012Co-Authors: J. Carneiro, A. J. D. Silvestre, Susana C M Fernandes, Carmen S.r. Freire, João Tedim, M. G. S. Ferreira, Alessandro Gandini, Mikhail L. ZheludkevichAbstract:The good film forming ability, specific solubility and versatile chemical functionalization of chitosan make it a promising candidate for “green” Protective Coatings. In the present work, these features are exploited together with chitosan high complexing ability to obtain inhibitor-containing anticorrosion Coatings for active protection of aluminum alloys. The functionalization of chitosan with fluorinated substituents was also evaluated as a possible route to improve barrier and surface properties of the coating matrix. It was observed that the chitosan layer worked as a reservoir for cationic Ce3+ corrosion inhibitor due to the complexation of Ce3+ with chitosan amino groups, which prevents its uncontrollable and fast leaching. These Ce-containing Coatings were found to confer active corrosion protection toward aluminum alloy 2024 as shown by electrochemical impedance spectroscopy. Moreover, the corrosion tests evidence the self-healing ability of prepared chitosan-based “green” Protective Coatings. The interaction between Ce3+ and chitosan and the concentration effect of the former on the performance of the latter from a corrosion standpoint is also discussed.
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Chitosan-based self-healing Protective Coatings doped with cerium nitrate for corrosion protection of aluminum alloy 2024
Progress in Organic Coatings, 2012Co-Authors: J. Carneiro, A. J. D. Silvestre, Susana C M Fernandes, Carmen S.r. Freire, João Tedim, M. G. S. Ferreira, Alessandro Gandini, Mikhail L. ZheludkevichAbstract:The good film forming ability, specific solubility and versatile chemical functionalization of chitosan make it a promising candidate for "green" Protective Coatings. In the present work, these features are exploited together with chitosan high complexing ability to obtain inhibitor-containing anticorrosion Coatings for active protection of aluminum alloys. The functionalization of chitosan with fluorinated substituents was also evaluated as a possible route to improve barrier and surface properties of the coating matrix. It was observed that the chitosan layer worked as a reservoir for cationic Ce 3+ corrosion inhibitor due to the complexation of Ce 3+ with chitosan amino groups, which prevents its uncontrollable and fast leaching. These Ce-containing Coatings were found to confer active corrosion protection toward aluminum alloy 2024 as shown by electrochemical impedance spectroscopy. Moreover, the corrosion tests evidence the self-healing ability of prepared chitosan-based "green" Protective Coatings. The interaction between Ce 3+ and chitosan and the concentration effect of the former on the performance of the latter from a corrosion standpoint is also discussed. © 2012 Elsevier B.V. All rights reserved.
Carmen S.r. Freire - One of the best experts on this subject based on the ideXlab platform.
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Chitosan-based self-healing Protective Coatings doped with cerium nitrate for corrosion protection of aluminum alloy 2024
Progress in Organic Coatings, 2012Co-Authors: J. Carneiro, A. J. D. Silvestre, Susana C M Fernandes, Carmen S.r. Freire, João Tedim, M. G. S. Ferreira, Alessandro Gandini, Mikhail L. ZheludkevichAbstract:The good film forming ability, specific solubility and versatile chemical functionalization of chitosan make it a promising candidate for “green” Protective Coatings. In the present work, these features are exploited together with chitosan high complexing ability to obtain inhibitor-containing anticorrosion Coatings for active protection of aluminum alloys. The functionalization of chitosan with fluorinated substituents was also evaluated as a possible route to improve barrier and surface properties of the coating matrix. It was observed that the chitosan layer worked as a reservoir for cationic Ce3+ corrosion inhibitor due to the complexation of Ce3+ with chitosan amino groups, which prevents its uncontrollable and fast leaching. These Ce-containing Coatings were found to confer active corrosion protection toward aluminum alloy 2024 as shown by electrochemical impedance spectroscopy. Moreover, the corrosion tests evidence the self-healing ability of prepared chitosan-based “green” Protective Coatings. The interaction between Ce3+ and chitosan and the concentration effect of the former on the performance of the latter from a corrosion standpoint is also discussed.
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Chitosan-based self-healing Protective Coatings doped with cerium nitrate for corrosion protection of aluminum alloy 2024
Progress in Organic Coatings, 2012Co-Authors: J. Carneiro, A. J. D. Silvestre, Susana C M Fernandes, Carmen S.r. Freire, João Tedim, M. G. S. Ferreira, Alessandro Gandini, Mikhail L. ZheludkevichAbstract:The good film forming ability, specific solubility and versatile chemical functionalization of chitosan make it a promising candidate for "green" Protective Coatings. In the present work, these features are exploited together with chitosan high complexing ability to obtain inhibitor-containing anticorrosion Coatings for active protection of aluminum alloys. The functionalization of chitosan with fluorinated substituents was also evaluated as a possible route to improve barrier and surface properties of the coating matrix. It was observed that the chitosan layer worked as a reservoir for cationic Ce 3+ corrosion inhibitor due to the complexation of Ce 3+ with chitosan amino groups, which prevents its uncontrollable and fast leaching. These Ce-containing Coatings were found to confer active corrosion protection toward aluminum alloy 2024 as shown by electrochemical impedance spectroscopy. Moreover, the corrosion tests evidence the self-healing ability of prepared chitosan-based "green" Protective Coatings. The interaction between Ce 3+ and chitosan and the concentration effect of the former on the performance of the latter from a corrosion standpoint is also discussed. © 2012 Elsevier B.V. All rights reserved.
