Electrochemical characterization of micro-cracks in polyurethane resin films deposited on metallic surfaces
| Autor: | Kyle Murphy, Rohan Akolkar, Daniel J. Lacks, Jean Zhao, Karun K. Rao, Molly Ferguson |
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| Rok vydání: | 2016 |
| Předmět: |
Materials science
General Chemical Engineering Ionic bonding chemistry.chemical_element 02 engineering and technology Electrolyte 010402 general chemistry 021001 nanoscience & nanotechnology Electrochemistry 01 natural sciences Copper 0104 chemical sciences Corrosion Anode chemistry.chemical_compound chemistry Polymer chemistry Materials Chemistry Surface modification Composite material 0210 nano-technology Polyurethane |
| Zdroj: | Journal of Applied Electrochemistry. 46:1237-1243 |
| ISSN: | 1572-8838 0021-891X |
| Popis: | Resin films based on polyurethane dispersions (PUDs) have recently gained substantial interest as surface protective coatings. However, defects in the resin films such as micro-cracks may induce high permeability to moisture, thereby compromising the coatings’ performance. In this contribution, we report on a simple electrochemical method for characterization of the micro-cracks in a resin film deposited on a copper surface. Electrochemical measurements are facilitated in a two-electrode cell where the resin-coated copper electrode serves as the anode. The ionic current flow due to electrolyte penetration within the micro-cracks of the resin film is measured and quantified. The ionic current (I) exhibits an inverse exponential dependence on the film thickness (x): I ∝ e−x . The physical basis for this dependence is discussed using a mathematical model that incorporates the surface fraction of micro-cracks in a layered resin film. While the analysis presented herein is for the specific case of PUD resins, the overall methodology is applicable to the characterization of many metallic and non-metallic surface coatings used in corrosion protection and surface functionalization applications. |
| Databáze: | OpenAIRE |
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