COLL 4 |
| P Somasundaran and Rui Zhang. NSF IUCUR Center for Advanced Studies in Novel Surfactants, Columbia University, 500 W120th Street, 911 Mudd, New York, NY 10027 |
| In order to develop structure-property relationships that control adsorption, solubilization and micellization behavior in mixed surfactant systems, and to develop theoretical models based on such relationships, it is necessary to acquire information on various species present in the systems. Analytical ultracentrifugation technique is applied for the first time to characterize species present in mixed micellar solution utilizing its ability to separate species based on their size and shape. The mixed surfactant system (n-dodecyl-â-D-maltoside (DM), nonyl-phenol ethoxylated decyl ether (NP-10)) was investigated using analytical ultracentrifuge. Interestingly, the results from both sedimentation velocity and sedimentation equilibrium experiments suggest coexistence of two types of mixed micelles. These results supplement our previous findings on similar systems studied using ultrafiltration techniques. A schematic model is proposed for the system made up of two types of micelles! Type I mixed micelles are prolate or oblate in shape while type II micelles are either cylindrical or network of cylindrical micelles. Amount of type II micelles increases with concentration because they were energetically favored. |
|
ACS Award in Colloid and Surface Chemistry Symposium Honoring Clay Radke
Division of Colloid and Surface Chemistry |