COLL 366 |
| Eric W Kaler1, Yamaira I. Gonzalez1, and Dganit Danino2. (1) Chemical Engineering, University of Delaware, Colburn Lab, 150 Academy St, Newark, DE 19716, (2) Department of Food Engineering and Biotechnology, Technion, Technion City, Haifa, 32000, Israel |
| Unexpected colloidal assemblies form in aqueous mixtures of sodium dodecylbenzene sulfonate (SDBS) with the imidazoline compounds: 2,2'-Azobis[2-(2-imidazolin-2-yl)propane] dihydrochloride (V-44), 2, 2’-tetramethylenedi-2-imidazoline (TMI), and the main recombination product (RP) from the decomposition of V-44. These imidazoline compounds act as hydrotropes, and as the molar ratio of imidazoline to SDBS increases, a gradual transition from micelles to vesicles to bilayers to precipitate is observed. In these mixtures, small unilamellar vesicles (< 80 nm in diameter) form spontaneously; although with time they coexist with a small amount of precipitate and their size increases steadily. The self-assembly of vesicles occurs over a wide range of compositions when the solution pH is lower than the pKa of the imidazoline moiety. At equimolar compositions of SDBS and RP, a novel colloidal structure with multiple closely packed bilayers is observed. |
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Surface and Colloid Chemistry Award Symposium Honoring Joseph Zasadzinski
8:10 AM-12:10 PM, Wednesday, March 31, 2004 Marriott -- Orange County 3, Oral
Division of Colloid and Surface Chemistry |