Effect of hydrocarbon chain branching on interfacial properties of monodisperse ethoxylated alcohol surfactants
| Autor: | Ramesh Varadaraj, Jan Bock, Stephen Zushma, Neil Brons, Teresa Colletti |
|---|---|
| Rok vydání: | 1991 |
| Předmět: |
chemistry.chemical_classification
Chemistry Branching (polymer chemistry) Surfaces Coatings and Films Electronic Optical and Magnetic Materials Hydrophobe Biomaterials Surface tension Colloid and Surface Chemistry Hydrocarbon Adsorption Chemical engineering Pulmonary surfactant Critical micelle concentration Organic chemistry Wetting |
| Zdroj: | Journal of Colloid and Interface Science. 147:387-395 |
| ISSN: | 0021-9797 |
| DOI: | 10.1016/0021-9797(91)90171-4 |
| Popis: | Surfactant properties at the air-water, decane-water, and Teflon-water interfaces are strongly influenced by branching of the hydrocarbon chain of an ethoxylate surfactant. Although chain branching reduces chain length, branched ethoxylates exhibit properties intermediate between those of linear surfactants of the same carbon number and linear surfactants of the same chain length. Steric factors that disfavor micellization in bulk result in enhancement of adsorption properties at interfaces. Compared to linear ethoxylates, branched ethoxylates with the same number of oxyethylene groups exhibit a higher critical micelle concentration and are more effective in reducing the surface tension at the air-water interface by occupying a larger area per molecule. Better dynamic air-water interfacial properties result from branching the hydrophobe as branched ethoxylates attain meso-equilibrium faster and the surface tension at meso-equilibrium is lower than the corresponding linear hydrophobe surfactant. At the decane-water interface the effect of branching on critical aggregation concentration and effectiveness in interfacial tension reduction depends on the nature of branching. The water wettability of a hydrophobic Teflon surface is enhanced by branched hydrocarbon chain ethoxylates. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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