You are not currently logged in.
Access your personal account or get JSTOR access through your library or other institution:
Yingxin Liu, Philip G. Jessop, Michael Cunningham, Charles A. Eckert and Charles L. Liotta
New Series, Vol. 313, No. 5789 (Aug. 18, 2006), pp. 958-960
Published by: American Association for the Advancement of Science
Stable URL: http://www.jstor.org/stable/3846977
Page Count: 3
Preview not available
Many industrial applications that rely on emulsions would benefit from an efficient, rapid method of breaking these emulsions at a specific desired stage. We report that long-chain alkyl amidine compounds can be reversibly transformed into charged surfactants by exposure to an atmosphere of carbon dioxide, thereby stabilizing water/alkane emulsions or, for the purpose of micro-suspension polymerization, styrene-in-water emulsions. Bubbling nitrogen, argon, or air through the amidinium bicarbonate solutions at 65°C reverses the reaction, releasing carbon dioxide and breaking the emulsion. We also find that the neutral amidines function as switchable demulsifiers of an aqueous crude oil emulsion, enhancing their practical potential.
Science © 2006 American Association for the Advancement of Science