Effects of organic solvents on the scission energy of rodlike micelles
Copyright 2004 American Chemical Society
| Veröffentlicht in: | Langmuir : the ACS journal of surfaces and colloids. - 1992. - 20(2004), 21 vom: 12. Okt., Seite 8970-4 |
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| 1. Verfasser: | |
| Weitere Verfasser: | , , |
| Format: | Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2004
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| Zugriff auf das übergeordnete Werk: | Langmuir : the ACS journal of surfaces and colloids |
| Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Erucic Acids Hexanes Micelles Quaternary Ammonium Compounds erucyl bis(hydroxyethyl) methylammonium chloride Ethanol 3K9958V90M |
| Zusammenfassung: | Copyright 2004 American Chemical Society The linear viscoelastic response of erucyl bis(hydroxyethyl) methylammonium chloride with added KCl has been studied as a function of temperature and nonpolar solvent addition. The plateau modulus is independent of temperature from 25 to 40 degrees C, in contrast to previous studies with salicylate counterions that showed a plateau modulus increasing with temperature over this range. The average micelle length, L, predicted by the model of Cates, depends experimentally on Escis/kBT, where Escis is the scission energy of the chain and kBT is the Boltzmann constant times the absolute temperature. With ethanol addition, the calculated average contour length, L, decreases by a factor of 4 as ethanol concentration varies from 0 to 1.3 M. This corresponds to an apparent energy for scission, Escis, decrease from 81 +/- 8 to 74 +/- 7 kJ/mol. On the other hand, only 80 mM of hexane is required to cause a decrease in Escis to the same level, and for hexane addition levels above 70 mM a disruption in the plateau modulus indicates the disruption of the rodlike structure. The correspondence between the effect of temperature and the effect of solvent addition allows the development of "solvent/temperature" superposition rules to predict the rheology of these viscoelastic fluids at elevated temperatures |
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| Beschreibung: | Date Completed 25.04.2006 Date Revised 21.11.2013 published: Print Citation Status MEDLINE |
| ISSN: | 1520-5827 |