COLL 439 |
| Blake A. Simmons1, James R. McElhanon1, Douglas A. Loy2, Gregory M. Jamison, Timothy M. Long3, David R. Wheeler4, Steven R. Kline5, Kamyar Rahimian6, Thomas Zifer1, and William R. Even Jr.1. (1) Materials Chemistry Department, Sandia National Laboratories, P.O. Box 969, MS 9403, Livermore, CA 94551, (2) Polymers and Coatings Department, Los Alamos National Laboratories, PO Box 1662, MS E549, Los Alamos, NM 87545, (3) Chemical Synthesis and Nanomaterials Department, Sandia National Laboratories, PO Box 5800, Albuquerque, NM 87185, (4) Micro-Total-Analytical Systems Department, Sandia National Laboratories, PO Box 5800, MS 0892, Albuquerque, NM 87185-0892, (5) NIST Center for Neutron Research, 100 Bureau Dr. Stop 8562, Bldg. 235/E151, Gaithersburg, MD 20899-8562, (6) Organic Materials Department, Sandia National Laboratories, P. O. Box 5800, MS 0888, Albuquerque, NM 87185-0888 |
| It is highly desirable to have surfactants that can be eliminated without calcining for a number of applications, including the synthesis of surfactant-templated mesoporous materials. Two new surfactant molecules are reported which contain thermally labile Diels-Alder adducts connecting the hydrophilic and hydrophobic sections of each molecule. The two surfactants possess identical hydrophobic dodecyl tail segments but differ with respect to hydrophilic head group (phenolic vs carboxylic). Anionic potassium salts of these surfactants are soluble in water, and the critical micelle concentration for each has been determined through dye solubilization and surface tension measurements. Small-angle neutron scattering indicates the presence of spherical micelles with radii ranging from 16.5 Å for the carboxylate salt to 18.8 Å for the phenolate salt. NMR, surface tension, and neutron scattering results confirm that the Diels-Alder adduct dissociation begins at 55 C and becomes pronounced at 70 C. This dissociation process appears to be irreversible. |
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Symposium in Memory of Arthur W. Adamson
2:00 PM-5:40 PM, Wednesday, March 31, 2004 Marriott -- Orange County 4, Oral
Division of Colloid and Surface Chemistry |