Tracking copper nanofiller evolution in polysiloxane during processing into SiOC ceramic

Polymer-derived ceramics are an interesting class of materials that have application in ultra-high temperature ceramic matrix composites, functional coatings, catalysis, biomedical devices, and energy storage. By starting as pre-ceramic polymers, they have access to polymer processing routes which allow the formation of complex shapes prior to processing into dense, ceramic materials. However, extreme densitification and volume shrinkage during processing often leads to cracking and void formation. To combat this, nanofillers are often added to the polymer matrix prior to processing, which add an unshrinkable component to the matrix and bolster mechanical properties. Despite their interest for several applications, fundamental research into the structural changes occurring during pyolysis and interactions between nanofiller and matrix occurring on the local scale is lacking. In this work, copper nanofiller is added to pre-ceramic polysiloxane, and the resulting composite is heated to 1000 °C. Total X-ray Scattering is taken at discrete temperatures during processing in an effort to understand average structure changes such as crystalline phase formation (high energy X-ray diffraction), local structure indications of pyrolysis in the matrix (pair distribution function), and local-scale interfacial reactions between nanofiller and matrix (differential-pair distribution functions). The total X-ray scattering data is reported in this Dryad repository. Methods This data was collected at the Advanced Photon Source 11-ID-B beamline (GUP-75644, wavelength 0.2115 Å). Sample-to-detector distances for XRD and PDF were 1m and 180mm, respectively. The data provided here have been calibrated and integrated into 1D I(q) scattering files (.chi format) in which column 1 is the scattering angle 2-theta in degrees and column 2 is integrated intensity. Calibration and integration were performed in GSAS-II using CeO2 (sample-to-detector distances) and Ni standards (instrumental parameters). The area around the beamstop was excluded from integration. For the PDF, scattering from the empty Kapton sample capillary was subtracted during integration.