Shear-induced mesostructure in nanoplatelet-polymer networks
نویسندگان
چکیده
The shear response of a model polymer–clay gel is measured using small-angle neutron and light scattering, optical microscopy, and rheometry. 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 pattern, while the clay platelets orient with their surface normal parallel to the direction of vorticity. We discuss similarities with shear-induced structural transitions observed in other complex fluids, and we offer a physical explanation for the orientation of the clay platelets. © 2003 American Institute of Physics. @DOI: 10.1063/1.1609972#
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