Regensburg 2016 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
CPP: Fachverband Chemische Physik und Polymerphysik
CPP 34: Crystallization, Nucleation, Self Assembly I (joint session CPP/DY, organized by CPP)
CPP 34.1: Hauptvortrag
Mittwoch, 9. März 2016, 09:30–10:00, H42
Polymer crystallization and nucleation: New insights from fast scanning calorimetry — •Christoph Schick1, Evgeny Zhuravlev1, and René Androsch2 — 1University of Rostock, Institute of Physics, 18051 Rostock — 2Martin-Luther-University Halle-Wittenberg, Center of Engineering Sciences, 06099 Halle/Saale
Crystallization commonly starts from a (sub)nanoscale nuclei which eventually growth to a crystal. Classical nucleation theory (CNT) provides a qualitative description of these processes. Nevertheless, CNT often fails to predict nucleation and crystallization on a quantitative level. Differential scanning calorimetry (DSC) is often employed to probe such complex phase transitions. The traditional DSC is limited in its cooling capability to cooling rates below 10 K/s. However, many materials are crystallizing, e.g. during processing, at much faster cooling rates (100 to a few 1000 K/s). Knowledge about the phase transitions on fast cooling is therefore required. Chip based calorimeters cover this range but so far they do not allow to obtain the full information for fast crystallizing materials like PE or PTFE. Faster controlled cooling and heating rates above 106 K/s are therefore required. These novel fast scanning calorimeters were used in combination with conventional DSC to study crystallization of polymers on fast cooling, isothermal crystallization after fast quenches, the efficiency of nucleating agents, the kinetics of crystal nucleation and the kinetics of the glass transition. The basic principle of the new technique and applications to polymeric and non-polymeric materials will be presented.