Measuring the alignment and breakdown of worm-like micelles at ultra-high shear rates

Worm-like micelle solutions will be measured in a high-shear capillary rheometer to better understand the microstructural alignment, breakdown, and shear thinning rheology. Our capillary rheometer, previously developed for neutron scattering [1], was modified to expand the accessible shear rates up to 10^7 s-1 when using high-flux X-ray sources. A non-monotonic change in micelle alignment [1] is hypothesized to occur from breakage of the micelles into shorter lengths at high shear rates. The USAXS 2D detector will enable measurement of both the micelle lengths (100-10000 nm) and orientation distribution of micelle radii (10 nm) as a function of shear rate and concentration. To our knowledge, such measurements are only possible at ID02 USAXS. If desirable, we are eager to share knowledge and rheometer design with others at the ESRF, further improving the rheometer for future users aiming to measure the rheology and nanostructure of complex fluids at high shear rates.