Simulations of dynamics and viscoelasticity in highly entangled solutions of semiflexible rods.
Brownian dynamics simulations are used to study highly entangled solutions of semiflexible polymers. Bending fluctuations of semiflexible rods are significantly affected by entanglement only above a concentration c(**), where c(**) approximately 10(3)L(-3) for chains of length L similar to their persistence length. For c>c(**), the tube radius R(e) approaches a dependence R(e) proportional to c(-35) and the linear viscoelastic response develops an elastic plateau that is absent for c<c(**). Experiments on isotropic solutions of F-actin are shown to span concentrations near c(**) for which the predicted asymptotic scaling of the plateau modulus, G proportional to c(75), is not yet valid.
Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, USA.
Shriram
S
Ramanathan
David C
DC
Morse