A combined small-angle neutron and X-ray scattering study of block copolymers micellisation in supercritical carbon dioxide

Small angle neutron and X-ray scattering (SANS and SAXS) are used to investigate the monomer-aggregate transition of fluorocarbon-hydrocarbon diblock copolymers in supercritical carbon dioxide. SANS data are analyzed using a polydisperse sphere core-shell model. Synchrotron SAXS data have been collected by profiling the pressure at different temperatures, and critical micellization densities have been obtained for a series of diblock solutions. Finally pressure jump experiments, combined with synchrotron SAXS, have revealed two steps in the dynamics of the formation of the aggregates.