The shear response of a model polymer-clay gel is measured using small-angle neutron and light scattering,optical microscopy,and rtheometry.As the flow disrupts the transient network that forms between clay and polymer,coupling between composition and stress leads to the formation of a macroscopic domain parrern,while the clay platelets orient iwht their surface normal parallel to the direction fo vorticity.We discuss similarities with shear-induced structural transitons observed in other complex fluids,and we offer a physical explanation for the orentation of the platelets.
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