COLL 421 |
| Ivan B. Ivanov, Nikolai D. Denkov, Krastanka G. Marinova, Slavka S. Tcholakova, and Theodor D. Gurkov. Laboratory of Chemical Physics & Engineering, Faculty of Chemistry, University of Sofia, 1 James Bourchier Avenue, 1164 Sofia, Bulgaria |
| During emulsion/foam formation, the (instantaneous) stabilizer adsorption plays a major role, because it determines the drop/bubble life time through two major factors: the disjoining pressure and the surface mobility. That is why we developed several techniques for measuring (i) the interfacial tension at very short times after the formation of the interface, and (ii) the drop/bubble life time under dynamic conditions. These methods allowed us to vary the adsorption on the surface of the colliding bubble/drop not only by varying the bulk concentration of the stabilizer, but also by varying the exposure time of the drop/bubble to the surfactant or protein solution. Experiments were performed with low molecular surfactants (both ionic and non-ionic) and proteins. The observed trends were similar no matter what the stabilizer was and how a given degree of surface coverage was achieved: small life-times at low coverage and sudden increase at a given degree of surface coverage. |
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ACS Award in Colloid and Surface Chemistry Symposium Honoring Clay Radke
Division of Colloid and Surface Chemistry |