Viscoelasticity of concentrated solutions of stiff polymers

Abstract

A solution of rodlike polymers forms a liquid-crystalline phase above a certain concentration. In this paper we derive the constitutive equation for such a system under a weak velocity gradient from the molecular-kinetic theory. The equation agrees with Leslie's phenomenological equation in the liquid-crystalline phase. The Leslie coefficients are expressed by molecular parameters such as the concentration, molecular weight and the order parameter.