Shear Banding in Telechelic Associative Polymers by Molecular Dynamics

Results on the shear flow of telechelic associative polymers using nonequilibrium molecular dynamics (NEMD) are presented. The particle stream velocities can be calculated from the peculiar velocities and the imposed velocity profile using a novel approach. The constitutive relationship stress-shear rate becomes nonmonotonic when the interaction force between hydrophobic sites is increased. This condition induces a steady banding flow, which arises under transient conditions as a local instability originated from the breakage of micellar aggregates, thus promoting the migration of these aggregates to regions of low velocity gradients. Here, for the first time, NEMD simulations predict the banding flow of associative polymers.