Wet- and Corrosive De-Adhesion Processes of Water-Borne Epoxy Film Coated Steel

Posner, R.; Santa, M.; Grundmeier, Guido

doi:10.1149/1.3525239

Cited by 22 publications

(31 citation statements)

References 42 publications

(125 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A counter flow of OHions from the site of the coating defect would balance the ionic flow, via the diffusion of O 2 through the film. This is illustrated schematically in Figure 6a, which shows that a preliminary period with localized cathodes and follows a mechanism that is similar to that previously reported for cathodic delamination or disbondment (39)(40)(41)(42)(43)(44)(45)(46)(47)(48)(49)(50).…”

Section: Effect Of Uv Irradiationsupporting

confidence: 74%

The Use of 3D-SVET for the Examination of Plasticized PVC Coatings: Effect of Deformation and UV Irradiation on Barrier Properties

et al. 2015

View full text Add to dashboard Cite

The three-dimensional Scanning Vibrating Electrode Technique (3D-SVET) has been used to investigate the effects of forming and UV irradiation on model plasticized PVC coatings and specifically the influence on the barrier properties of the coating. In addition, an industrially produced coating that had undergone outdoor exposure (for approximately seventeen years) was analyzed as a comparison. Results from the investigation show a significant correlation between the corrosion observed on the model samples when compared to the naturally weathered material.

show abstract

Section: Effect Of Uv Irradiationsupporting

confidence: 74%

The Use of 3D-SVET for the Examination of Plasticized PVC Coatings: Effect of Deformation and UV Irradiation on Barrier Properties

et al. 2015

View full text Add to dashboard Cite

show abstract

“…8 ) A further consequence is that the coating may start to delaminate, exposing more free metal surface. 9 The fastest mechanism of coating delamination initiated from a defect is cathodic delamination. 5 It is assumed that reactive intermediates formed as product of the oxygen reduction reaction are the cause for the debonding of the coating from the metal.…”

mentioning

confidence: 99%

Cyclodextrins as Carriers for Organic Corrosion Inhibitors in Organic Coatings

Altin

Rohwerder

Erbe

2017

J. Electrochem. Soc.

View full text Add to dashboard Cite

Coatings are widely applied on metal surfaces for protection against corrosion. Once a coating is damaged and a defect is filled by aqueous solutions, delamination of the coating initiates further materials degradation. Cathodic delamination can be suppressed by adding active additives to the coating matrix. In this study, the impact was investigated of β-cyclodextrin inhibitor complex (β-CD [Inh]) additives in polyvinylbutyral model coatings on the cathodic delamination of coatings on zinc, using the scanning Kelvin probe (SKP). With the presence of the β-CD [Inh] in the coating, a decrease was observed of the delamination rate to 1/4 of that in the reference system without β-CD [Inh]. Release experiments using UV-Vis spectroscopy showed that in the presence of cyclodextrins, the released concentration of the inhibitor 2-mercaptobenzothiazole from the coating increased. The increase was most pronounced under alkaline conditions, where the released concentration within 24 h increased by a factor of 6 compared to a reference system without β-CD. Zinc and its alloys are industrial products for cathodic corrosion protection of steel components. They are hence used in a variety of applications, e.g. in metallic coatings.1 On the other hand, zinc may corrode itself actively, which is why a protection of the metal is needed. A straightforward way to protect non-noble metals such as zinc against corrosion is the application of organic coatings. 2-4

show abstract

“…1 The SKP approach was continued to determine whether the same applies to ␥-GPS modified polymer coated steel. A defect in the epoxy layer was covered with 0.5 M KBr solution, and the sample was exposed to humid air.…”

Section: Resultsmentioning

confidence: 99%

Wet- and Corrosive De-Adhesion Processes of Water-Borne Epoxy Film Coated Steel

Santa¹,

Posner²,

Grundmeier³

2011

J. Electrochem. Soc.

Self Cite

View full text Add to dashboard Cite

Low carbon steel substrates were covered with a ␥-glycidoxypropyltrimethoxysilane ͑␥-GPS͒ modified epoxy layer. Electrochemical impedance spectroscopy and attenuated total reflection infrared spectroscopy were used to investigate the barrier properties of the coating. The resistance of the samples to ion transport processes along the epoxy/steel interface was determined by in situ scanning Kelvin probe ͑SKP͒ measurements of the interface potential. X-ray photoelectron spectroscopy studies helped to analyze the resulting ion distribution on the substrate surface. The application of ␥-GPS resulted in a reduction of the interfacial water activity and temporarily stabilized the polymer/steel interface. In contrast to the experiments with the unmodified epoxy coating, interfacial ion transport processes were verifiable with the SKP. After some days of sample exposure to humid air, the stabilizing effect of ␥-GPS diminished and SKP potential profiles had to be recorded in dry atmosphere to identify the electrolyte front position, zones of cation and anion separation, and areas of local corrosion damage at the interface. This approach seems to be generally promising to analyze the degradation state of polymer/oxide/metal interfaces after long-term exposures in humid air.In Part I of this paper, the properties of a water-borne epoxy coating were analyzed. It was focused on the effect of high water activities and on the characteristics of ion transport processes at epoxy/steel interfaces. 1 Electrochemical impedance spectroscopy ͑EIS͒ indicated poor barrier properties of the polymer films. It was estimated that the H 2 O uptake level was very high and that strong wet adhesion processes occurred in humid air at the polymer/steel interface compared to substrates coated with common non-waterborne epoxy coatings. 2 Oxygen reduction induced ion transport processes along the epoxy/steel interface were not verifiable with the scanning Kelvin probe ͑SKP͒ because no characteristic sigmoid potential profiles were detected. Instead, the SKP recorded a nonspecific linear profile with a small slope. It was not possible to determine an electrolyte front position unless the humidity of the surrounding atmosphere was reduced. 1 Moreover, it was shown that both cations and anions of the defect electrolyte penetrated the epoxy/steel interface after the initialization of interfacial ion transport processes. With respect to previous studies, 3-9 it was discussed that the unexpected and uncommon anion transport was supported by the effects of fluid dynamics at the interface rather than by ion diffusion.This part of the study complements and continues the experimental approach selected in Part I. 1 It will be analyzed which effects a modification of the epoxy/steel interface with ␥-glycidoxypropyltrimethoxysilane ͑␥-GPS͒ has on the interface potentials and on the detectability of interfacial ion transport processes. Interfaces modified with adhesion promoting molecules, such as ␥-GPS, are expected to be more stable in an environment of a high ...

show abstract

Wet- and Corrosive De-Adhesion Processes of Water-Borne Epoxy Film Coated Steel

Cited by 22 publications

References 42 publications

The Use of 3D-SVET for the Examination of Plasticized PVC Coatings: Effect of Deformation and UV Irradiation on Barrier Properties

The Use of 3D-SVET for the Examination of Plasticized PVC Coatings: Effect of Deformation and UV Irradiation on Barrier Properties

Cyclodextrins as Carriers for Organic Corrosion Inhibitors in Organic Coatings

Wet- and Corrosive De-Adhesion Processes of Water-Borne Epoxy Film Coated Steel

Contact Info

Product

Resources

About