Micro scale distribution of nanoparticles studied with X-ray near-field scattering

In the present study, we investigate the micron-scale inhomogeneous distribution of silica nanoparticles with X-ray near-field scattering. This technique allows us to measure structures of soft matters on a large size scale that is complementary to conventional ultra-small-angle X-ray scattering and/or X-ray imaging. We applied the technique to the observation of the anisotropic structural distribution of silica aggregates in uniaxially stretched rubber. The scattering images show anisotropic butterfly patterns that correspond to the inhomogeneous density distribution of silica aggregates. The spatial distribution of the inhomogeneity in the stretched rubber cab also be determined by this technique.