Regensburg 2002 – wissenschaftliches Programm

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CPP: Chemische Physik und Polymerphysik

CPP 1: Struktur und Dynamik in Polymersystemen I

CPP 1.2: Vortrag

Montag, 11. März 2002, 11:20–11:40, H38

The Structure of the Growing Lamellae - Combined Scattering Experiments on s-Polypropylene and Polycaprolactone — •Michael Grasruck and Gert Strobl — Fakultät für Physik, Universität Freiburg, Hermann-Herder-Str. 3, 79104 Freiburg

We report about SWAXS experiments on s-polypropylene and polycaprolactone. While the density difference between the crystalline lamellae and the amorphous regions is detected in the small-angle scattering (SAXS), the amount of chains in crystalline order is observed in the wide-angle range (WAXS). For low undercoolings the experiment shows differences in the time evolution of the SAXS and the WAXS signal. At the beginning of the crystallization process the density difference, as represented by the Porod constant, increases faster than the integral-intensity of the Bragg peaks in the WAXS signal. The observation indicates a structural change in the growing lamellae in the sense of a continuous improvement of the order of the chains in the lamellae.