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SYPE: Symposium Polyelectrolytes
SYPE 1: Polyelectrolytes Poster
SYPE 1.5: Poster
Mittwoch, 28. März 2007, 16:00–18:30, Poster B
Effective charge of polyelectrolytes as a function of the solvent permittivity — •Ute Böhme and Ulrich Scheler — Leibniz Institute for Polymer Research Dresden, Hohe Strasse 6, D-01069 Dresden, Germany
One important issue in polyelectrolyte research is the determination of the effective charge, the charge which is capable of interacting with other molecules or solid surfaces. Due to counterion condensation the nominal charge is significantly reduced, depending on the nominal charge density of the polyelectrolyte, potential additional salt ions, the pH and the dielectric properties of the solvent. The effective charge of polyelectrolytes in organic solvents with varying dielectric constants has been derived from a combination of electrophoretic mobility and diffusion coefficient [1], both obtained from PFG NMR experiments. Decreasing permittivity of the solvent results in a drastically reduced effective charge and in changing conformation of the polyelectrolytes simultaneously.
[1] U. Scheler, in H.S. Nalva (ed.) *Handbook of Polyelectrolytes and their applications*, American Scientific Publishers (2002)