Rheo-XPCS

We review recent efforts and discuss future prospects in research employing X-ray photon correlation spectroscopy (XPCS) to interrogate the nanometer-scale structural dynamics of soft materials undergoing in situ mechanical deformation and flow. Examples of such rheo-XPCS experiments include those incorporating conventional homogeneous shear deformation, including notably large amplitude oscillatory shear (LAOS), as well as other modes of flow and deformation, such as tensile strain and flow within microfluidic environments. Particular attention is given to opportunities in such studies to reveal the structural dynamics associated with nonlinear rheological behavior such as yielding. We also review recent related work employing XPCS as a microrheological tool by tracking nanoparticle mobility within complex fluids. (C) 2015 Elsevier Ltd. All rights reserved.