Polyelectrolyte solutions + multivalent salts = phase separation |
| |
Authors: | L Belloni M Olvera de la Cruz M Delsanti J P Dalbiez O Spalla M Drifford |
| |
Institution: | (1) Service de Chimie Moléculaire, CEA, DRECAM, CE Saclay, 91191 Gif-sur-Yvette Cedex, France;(2) Present address: Department of Material Science and Engineering, Northwestern University, 60208 Evanston, IL, USA |
| |
Abstract: | Summary A queous solutions of highly charged flexible polyelectrolytes phase separate in the presence of multivalent counterions.
We present a theoretical model which explains this behavior in terms of electrostatic bridging between monomers via the condensed
counterions. The ?Polymer Reference Interaction Site Model? with the Debye-Hückel closure (equivalent to the ?Random Phase
Approximation?) is sufficient to understand the crucial role of the valency of the counterions, to predict a demixion above
a given valency and a redissolution of the precipitate in excess of added salt. The model successfully reproduces the different
experimental phase diagrams of polystyrene sulfonate suspensions with different added electrolytes.
Paper presented at the I International Conference on Scaling Concepts and Complex Fluids, Copanello, Italy, July 4–8, 1994. |
| |
Keywords: | Polymers elastomers and plastics |
本文献已被 SpringerLink 等数据库收录! |
|