Structure-rheology relationships of dense microgel suspensions with varying degrees of particle softness

We propose to measure the macroscopic rheology and microstructure of a model system of dense soft microgel particle suspensions using a unique combination of high-shear capillary rheometry and USAXS. Recent measurements revealed distinct differences in shear-thinning viscosity and particle shape depending on the shear rate and particle softness (crosslink density). To our knowledge, USAXS is the only instrument able to measure low q (0.005 nm-1) and capture 2D scattering data necessary to probe anisotropic scattering of relatively large particles (D ~ 260 nm). In addition, the ESRF provides sufficiently high flux needed for small sample volumes (0.25 mm pathlength) and small beam sizes (50 µm) to probe different flow-planes within the thin capillary. Results from this work will be of significant interest to the rheological and colloidal communities, who aim to understand the effects of particle softness on colloidal suspension rheology.