Correlations and dynamics of polyelectrolyte solutions

Abstract

The dynamics of polyelectrolyte solutions have been studied using a neutron spin echo spectrometer for wave vectors q around the maximum of the static structure factor (qm). The q dependent diffusion coefficient D(q) decreases sharply below q = qm, and is nearly constant above qm. All these features can be understood in terms of a new picture for the correlations, based on : i) the notion of a correlation hole, of diameter ξ = aO-1/2 ; ii) locally rigid chains with a persistence length b = aO-1 (where O is the polymer volume fraction and a the monomer size).