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Updated: May 11, 2026

Dielectric RheoSANS — Simultaneous Interrogation of Impedance, Rheology and Small Angle Neutron Scattering of Complex Fluids
Published on: April 10, 2017
Note: Effects of adding a viscosity-increasing 2 nm-size molecule on dielectric relaxation features and the dynamic
1Department of Materials Science and Engineering, McMaster University, Hamilton, Ontario L8S 4L7, Canada.
Abstract:
To investigate the extent to which dynamic heterogeneity determines the relaxation features, we studied the effect of adding a viscosity-increasing, ∼2 nm size polyhederal oligomeric silsesquioxane (POSS) molecule on dielectric relaxation. Addition of POSS increased the relaxation time of the α-process, τ(m,α), and decreased the non-exponential response parameter, β, which is compatible with the dynamic heterogeneity view. But β varied monotonically with the composition, and there was little variation of β with the temperature, which seems incompatible with that view. Effects of adding nm-size particles in simulations may reveal how the size of dynamically heterogeneous regions affects τ(m,α) and β.
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