Effective viscosity of dilute polymer solutions near confining boundaries

摘要

The problem of a beadndash;spring model macromolecule in the presence of impenetrable interfaces is studied. Equilibrium partition coefficients are calculated for various pore geometries and are compared to data on partitioning in porous chromatographic columns. Impenetrable, purely repulsive interfaces strongly affect viscosity, resulting in apparent slip at the interfaces. The beadndash;spring contribution to the stress in the presence of walls is calculated at low shear rates and compared to recent data on dilute Xanthan polysaccharide solutions. The analysis compares well with data on solutions of low polymer concentration at low shear rates.