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Updated: Aug 11, 2026

Phase Behavior of Charged Vesicles Under Symmetric and Asymmetric Solution Conditions Monitored with Fluorescence Microscopy
Published on: October 24, 2017
Clouding: origin of phase separation in oppositely charged polyelectrolyte/surfactant mixed solutions
Yun Yan1, Li Li, Heinz Hoffmann
1Bayreuther Zentrum für Kolloid und Grenzflächen, Universität Bayreuth, Gottlieb-keim Strasse 60, 95448, Germany. yun.yan@wur.nl
Abstract:
The phase behavior in the system of cationic modified poly(vinyl alcohol) (CPVA)-sodium dodecylsulfate (SDS)-water has been investigated. Samples were found phase separated near electroneutral mixing at CPVA concentrations < or =6%, while in a medium CPVA concentration of 7-12%, the phase separation disappeared and the system transformed into bluish homogeneous solution. At > or =13% CPVA concentrations, the mixed systems became colorless homogeneous. Preclouding phenomenon was observed in 5-8% CPVA-SDS mixed systems at an electroneutral mixing ratio. The addition of inorganic salts, such as Na2SO4, NaCl, NaBr, and NaSCN, could exclude the bluish and phase separation phenomenon that was found to be caused by the increase of clouding point in these systems. The clouding phenomenon was proven to be the origin of the phase separation in the CPVA-SDS mixed system. The ability for the inorganic salts to increase the clouding point follows the order of the Hofmeister series.
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