Contrast-matching gone wrong? A study of polymer conformation in nanocomposites

International audienceThe structure of polymer nanocomposites has important consequences on final properties, like for instance mechanical reinforcement. While the structure of the hard filler phase is usually characterized by electron microscopy and small-angle X-ray scattering, the chain conformation can only be measured by small-angle neutron scattering (SANS). Continuous efforts over the past 15 years have produced a body of sometimes contradictory, because system-dependent, results. In virtually all studies, however, a mismatch ruining the polymer form factor at low-angles has been observed, in spite of careful contrast-matching. In this study, the conformation of polymer chains in silica-latex-nanocomposites has been studied under zero-average contrast conditions using SANS