Combined XPS and contact angle studies of flat and rough ethylene-vinyl acetate copolymer films
| Autor: | Ikrime O. Ucar, J.A. Mielczarski, C. E. Cansoy, M. D. Doganci, H. Y. Erbil, E. Mielczarski |
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| Rok vydání: | 2011 |
| Předmět: |
chemistry.chemical_classification
Materials science Polymers and Plastics Analytical chemistry Ethylene-vinyl acetate General Chemistry Polymer Dip-coating Surface energy Surfaces Coatings and Films Contact angle Low-density polyethylene chemistry.chemical_compound chemistry X-ray photoelectron spectroscopy Polymer chemistry Materials Chemistry Thin film |
| Zdroj: | Journal of Applied Polymer Science. 124:2100-2109 |
| ISSN: | 0021-8995 |
| Popis: | Flat and rough thin films were prepared by dip coating using LDPE, PVAc, and EVA polymers containing 12–40% VA contents. Surface free energy of flat films was determined by measuring contact angles. Surface atomic composition was investigated by XPS at 0° and 60° take-off angles. XPS results show that hydrophobic PE component was found to enrich at the near-surface region for all EVA samples for a depth of ∼ 5 nm for both flat and rough surfaces, whereas hydrophilic VA component was enriched on the surface when VA < 18% for only at 10 nm depth. The difference between the XPS results of the flat and rough surfaces was not significant for EVA samples except EVA-33 surface where the atomic oxygen content decreased 15–20% for rough surfaces. Contact angle hysteresis values for the rough samples were much larger than that of the flat samples for LDPE and EVA-12 surfaces due to the presence of partial trapping of air pockets on these rough surfaces. A good agreement was obtained between surface concentration of atomic oxygen in the 5 nm outermost layer and γ surface free energy component especially for the samples having high VA contents. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 |
| Databáze: | OpenAIRE |
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