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dc.contributor.authorLoizou, Elenaen
dc.contributor.authorButler, P.en
dc.contributor.authorPorcar, L.en
dc.contributor.authorSchmidt, G.en
dc.creatorLoizou, Elenaen
dc.creatorButler, P.en
dc.creatorPorcar, L.en
dc.creatorSchmidt, G.en
dc.description.abstractThe shear response of a series of polymer-clay gels has been investigated by means of rheology and small-angle neutron scattering (SANS). The gels have the same composition by mass but different polymer molecular weights (M w). While long polymer chains can interconnect several platelets, which act as multifunctional cross-links, very short polymer chains should not be able to do so, allowing us to explore the effects of bridging on structure and dynamical responses. Increasing the polymer M w in the gels leads to increasingly strong anisotropy in the SANS data, indicating a larger and larger degree of shear orientation. This relative increase in orientation, however, is accompanied by a relatively lower amount of shear thinning. Simple solutions of anisotropic particles usually shear thin by alignment of the particles with the flow, allowing them for example to slide past each other more easily. In a connected gel, breaking of the connectivity should also lead to shear thinning. Thus, the inverse relationship between shear orientation and shear thinning, combined with the fact that the lowest M w, which exhibits the highest shear thinning, does not orient at all, supports our earlier hypothesis that the alignment mechanism in these systems stems from the coupling between the clay and the polymer mediated by the shear flow and nicely demonstrates the effect of bridging on the strength and dynamics of these gels. © 2006 American Chemical Society.en
dc.subjectShear flowen
dc.subjectShear thinningen
dc.subjectNanostructured materialsen
dc.subjectDynamic responseen
dc.subjectMolecular weighten
dc.subjectPolymer chainsen
dc.subjectNanocomposite hydrogelsen
dc.titleDynamic responses in nanocomposite hydrogelsen
dc.description.endingpage1619 Σχολή Θετικών και Εφαρμοσμένων Επιστημών / Faculty of Pure and Applied SciencesΤμήμα Χημείας / Department of Chemistry
dc.description.notes<p>Cited By :49</p>en

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