Analysis of Shear-Thickening in Physical Gel. A Stochastic Theory for Polymer Networks

Original · EN

A formula of steady shear viscosity is derived by introducing a model to describe the dynamics of physically cross-linked network (physical gel), and successfully analyzes the shear-thickening behavior observed in HEUR aqueous solutions by Jenkins, Sileibi and El-Aasser. We take into account the effects of looped chains at junctions which detach their one end from the junction as the shear rate increases due to the collisions with other chains. This process produces the weak and wide enhancement of the number of chains whose both ends stick to the separate junctions (active chains) leading to the weak increase in the shear viscosity. It is also shown that the nonlinear force sustained by active chains induces the strong and sharp enhancement of the steady shear viscosity.