Effects of attraction strength on microchannel flow of colloid–polymer depletion mixtures

Abstract

We investigated the effect of the strength of the interparticle attraction on the flow properties and microstructure of colloid–polymer depletion mixtures during microchannel flow. When the strength of the interparticle attraction is increased, the additional elasticity imparted by the formation of interparticle bonds does not modify the magnitude of the flow velocities downstream, but instead leads to changes in the flow profiles near the edges of the microchannel that reflect yielding at the weak bonds between clusters. As a result, increasing the strength of attraction increases the resistance of the suspension to densification and to shear-induced migration.