Dresden 2020 – wissenschaftliches Programm
Die DPG-Frühjahrstagung in Dresden musste abgesagt werden! Lesen Sie mehr ...
CPP 98.8: Vortrag
Donnerstag, 19. März 2020, 16:45–17:00, ZEU 114
Calorimetric study on the vitrification kinetics, molecular mobility and rigid amorphous fraction in epoxy-based nanocomposites — •Paulina Szymoniak, Xintong Qu, and Andreas Schönhals — Bundesanstalt für Materialforschung und prüfung (BAM), Berlin, Germany
It was found for inorganic/polymer nanocomposites that a so-called rigid amorphous phase (RAF) is formed in the interfacial region by adsorption of polymer segments onto the nanoparticles. The segmental dynamics of RAF is expected to be altered, as compared to the pure matrix, which might percolate into the entire system, affecting the overall PNC properties. Here, the structure and molecular mobility of epoxy-based PNCs with different nanofillers (layered double hydroxide and boehmite) was studied by a combination of calorimetric and X-Ray scattering techniques. Temperature modulated DSC (TMDSC) showed that depending on the nanofiller, RAF can reach up to 40 wt % of the system or, on the contrary, the overall mobility of the matrix might increase due to the presence of particles. Such contrasting results, including the high amount of RAF, which was never shown before for epoxy-based PNCs, emphasize the importance of interfaces. Additionally, glass transition and glassy dynamics were investigated by a novel technique, Flash DSC (heating rates up to 10 kK/s) employed for the first time to a thermosetting system. It was used to study both the vitrification kinetics and glassy dynamics of the PNCs, for instance further confirming the presence of RAF and its impact on the overall material properties.