Characterization of Polymer Adsorption and Interfacial Structure in Nanocomposites via Polarized Resonant Soft X-ray Scattering

Interfacial interactions between polymers and nanofillers strongly influence nanocomposite performance. When polymer chains adsorb onto nanoparticles, they form nanoscale regions with structures and dynamics distinct from the bulk. These interfacial regions are critical to macroscopic behavior yet remain difficult to study because they are only a few nanometers thick and obscured by the surrounding matrix.

To overcome these challenges, this work uses Polarized Resonant Soft X-ray Scattering (p-RSoXS) as a non-destructive probe of polymer adsorption in nanocomposites. This technique measures molecular orientation and structural organization within adsorbed layers under native conditions, providing insight into chain conformation while preserving the adsorbed structure.

Polystyrene-silica nanocomposites were characterized at the SST-1 RSoXS beamline using polarized X-rays to detect nanoscale anisotropy. Scattering data were analyzed using open-source, NIST-developed software, with PyHyperScattering for data processing and the NIST RSoXS Simulation Suite for modeling and quantitative interpretation of interfacial structure. This approach offers new insight into adsorbed chain conformations and establishes a framework for examining adsorption-driven structure in polymer nanocomposites, thin films, and coatings, ultimately enabling evaluation of the relationship between interfacial molecular orientation and macroscopic performance.