The Thickness and Structure of Dip-Coated Polymer Films in the Liquid and Solid States
Films formed by dip coating brass wires with dilute and semi-dilute solutions of polyvinyl butyral in benzyl alcohol were studied in their liquid and solid states. While dilute and semi-dilute solutions behaved as Maxwell viscoelastic fluids, the thickness of the liquid films followed the Landau-Lev...
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-06-01
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| Series: | Micromachines |
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| Online Access: | https://www.mdpi.com/2072-666X/13/7/982 |
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| author | Zhao Zhang Fei Peng Konstantin G. Kornev |
| author_facet | Zhao Zhang Fei Peng Konstantin G. Kornev |
| author_sort | Zhao Zhang |
| collection | DOAJ |
| description | Films formed by dip coating brass wires with dilute and semi-dilute solutions of polyvinyl butyral in benzyl alcohol were studied in their liquid and solid states. While dilute and semi-dilute solutions behaved as Maxwell viscoelastic fluids, the thickness of the liquid films followed the Landau-Levich-Derjaguin prediction for Newtonian fluids. At a very slow rate of coating, the film thickness was difficult to evaluate. Therefore, the dynamic contact angle was studied in detail. We discovered that polymer additives preserve the advancing contact angle at its static value while the receding contact angle follows the Cox–Voinov theory. In contrast, the thickness of solid films does not correlate with the Landau-Levich-Derjaguin predictions. Only solutions of high-molecular-weight polymers form smooth solid films. Solutions of low-molecular-weight polymers may form either solid films with an inhomogeneous roughness or solid polymer domains separated by the dry substrate. In technological applications, very dilute polymer solutions of high-molecular-weight polymers can be used to avoid inhomogeneities in solid films. These solutions form smooth solid films, and the film thickness can be controlled by the experimental coating conditions. |
| first_indexed | 2024-03-09T13:22:47Z |
| format | Article |
| id | doaj.art-d3ab64df643b4cfe94175cbb779730a3 |
| institution | Directory Open Access Journal |
| issn | 2072-666X |
| language | English |
| last_indexed | 2024-03-09T13:22:47Z |
| publishDate | 2022-06-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Micromachines |
| spelling | doaj.art-d3ab64df643b4cfe94175cbb779730a32023-11-30T21:28:30ZengMDPI AGMicromachines2072-666X2022-06-0113798210.3390/mi13070982The Thickness and Structure of Dip-Coated Polymer Films in the Liquid and Solid StatesZhao Zhang0Fei Peng1Konstantin G. Kornev2Department of Materials Science and Engineering, Clemson University, Clemson, SC 29634, USADepartment of Materials Science and Engineering, Clemson University, Clemson, SC 29634, USADepartment of Materials Science and Engineering, Clemson University, Clemson, SC 29634, USAFilms formed by dip coating brass wires with dilute and semi-dilute solutions of polyvinyl butyral in benzyl alcohol were studied in their liquid and solid states. While dilute and semi-dilute solutions behaved as Maxwell viscoelastic fluids, the thickness of the liquid films followed the Landau-Levich-Derjaguin prediction for Newtonian fluids. At a very slow rate of coating, the film thickness was difficult to evaluate. Therefore, the dynamic contact angle was studied in detail. We discovered that polymer additives preserve the advancing contact angle at its static value while the receding contact angle follows the Cox–Voinov theory. In contrast, the thickness of solid films does not correlate with the Landau-Levich-Derjaguin predictions. Only solutions of high-molecular-weight polymers form smooth solid films. Solutions of low-molecular-weight polymers may form either solid films with an inhomogeneous roughness or solid polymer domains separated by the dry substrate. In technological applications, very dilute polymer solutions of high-molecular-weight polymers can be used to avoid inhomogeneities in solid films. These solutions form smooth solid films, and the film thickness can be controlled by the experimental coating conditions.https://www.mdpi.com/2072-666X/13/7/982dip coatingLandau-Levich-Derjaguin theorypolymer solutionssolid films |
| spellingShingle | Zhao Zhang Fei Peng Konstantin G. Kornev The Thickness and Structure of Dip-Coated Polymer Films in the Liquid and Solid States Micromachines dip coating Landau-Levich-Derjaguin theory polymer solutions solid films |
| title | The Thickness and Structure of Dip-Coated Polymer Films in the Liquid and Solid States |
| title_full | The Thickness and Structure of Dip-Coated Polymer Films in the Liquid and Solid States |
| title_fullStr | The Thickness and Structure of Dip-Coated Polymer Films in the Liquid and Solid States |
| title_full_unstemmed | The Thickness and Structure of Dip-Coated Polymer Films in the Liquid and Solid States |
| title_short | The Thickness and Structure of Dip-Coated Polymer Films in the Liquid and Solid States |
| title_sort | thickness and structure of dip coated polymer films in the liquid and solid states |
| topic | dip coating Landau-Levich-Derjaguin theory polymer solutions solid films |
| url | https://www.mdpi.com/2072-666X/13/7/982 |
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