Dynamics of Semidilute Polyelectrolyte Solutions

We apply dynamic scaling to both unentangled and entangled semidilute polyelectrolyte solutions. The unentangled semidilute regime can span three to four decades of polymer concentration in low-salt solutions. In this range we predict such phenomena as a concentration independent self-diffusion coefficient, relaxation time that is a decreasing function of concentration $c$, and explain the empirical Fuoss law for the viscosity $\eta \sim c^{\frac{1}{2}}$. In the low-salt entangled regime we predict the concentration independent relaxation time and the viscosity $\eta \sim c^{\frac{3}{2}}$ that are observed experimentally.