COLL 259 |
| Yongfu Wu, PEER Center/California Institute of Technology, 738 Arrow Grand Circle, Covina, CA 91722 and Milton J. Rosen, Surfactant Research Institute, Brooklyn College of the City University of New York, Department of Chemistry, 2900 Bedford Avenue, Brooklyn, NY 11210. |
| Spreading of a liquid on a solid surface and wetting of the solid surface by liquid are basic components in many natural processes and commercial technologies. The enhancement of spreading of aqueous solutions on hydrophobic surfaces is a “performance property” of surfactants that is important in many industrial and consumer processes. However, on highly hydrophobic surfaces, many surfactants are not suitable for this purpose, since their aqueous solutions do not spread well on these surfaces. The spreading factors of aqueous solutions of surfactants with straight or branched alkyl or alkyl phenyl hydrocarbon chains and of their mixtures were measured on polyethylene. For individual ethoxylated alcohol surfactants, their spreading factors decrease with increase in the number of oxyethylene groups. For individual N-alkyl pyrrolidinone surfactants, their spreading factors increase with increase in hydrocarbon chain length. Strong synergism in the spreading of some surfactant mixtures was found. For certain cationic and ionic mixtures, although the two individual components have very small spreading factors, when they are mixed in certain ratios, the spreading factor for their mixture can be enhanced greatly, even approaching the spreading factors of trisiloxane-based “superspreading” surfactants on the polyethylene film. |
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Vibrational Analyses of Dry and Wet Surfaces
6:00 PM-8:00 PM, Monday, March 29, 2004 Disneyland -- North Exhibit Hall, Poster
Division of Colloid and Surface Chemistry |