COLL 420 |
| Ratchadaporn Chaisalee1, Sukhwan Soontravanich2, Nantaya Yanumet1, and John F Scamehorn2. (1) Petroleum and Petrochemical College, Chulalongkorn University, Phya Thai Avenue, Soi Chula 12, Bangkok, 10330, Thailand, (2) Institute for Applied Surfactant Research, University of Oklahoma, 100 E Boyd, SEC T-335, Norman, OK 73019 |
| It is well-known that aqueous solutions of nonionic surfactants exhibit low foaming above their cloud point. The cloud point is a temperature above which the homogeneous solution separates into two phases: a dilute phase containing a low surfactant concentration; and a coacervate phase which contains a very high surfactant concentration (e.g., 20 wt % surfactant). In this work, foam formation was measured for the dilute phase, the coacervate, and the mixed solution using the Ross-Miles method for nonylphenol polyethoxylates with 8, 9, or 10 ethylene oxides per molecule. The coacervate phase has been shown to be acting as an oil droplet antifoam to the dilute phase. Entering, spreading, and bridging coefficients for this system from surface and interfacial tension data make it appear probable that the coacervate phase is forming bridges across the film lamellae of the dilute phase foam and acting to suppress foam formation through the bridging mechanism.
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ACS Award in Colloid and Surface Chemistry Symposium Honoring Clay Radke
Division of Colloid and Surface Chemistry |