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CPP: Chemische Physik und Polymerphysik
CPP 6: Poster: Neue Methoden
CPP 6.5: Poster
Montag, 11. März 2002, 13:30–15:00, B
Free Volume changes in polymers induced by mechanical milling — •Katja Günther-Schade1, Hessel L. Castricum2, Hans J. Ziegler3, Hans Bakker2, and Franz Faupel1 — 1Technische Fakultät der Universität Kiel, Lehrstuhl für Materialverbunde, Kaiserstr. 2, 24143 Kiel, Germany — 2Van der Waals-Zeeman Instituut, Universiteit van Amsterdam, Valckenierstraat 65, 1018 XE Amsterdam, The Netherlands — 3GKSS Forschungszentrum, Institut für Chemie, Kantstr. 55, 14513 Teltow, Germany
The influence of mechanical milling on polymers was investigated for polystyrene (PS) and BPA-polycarbonate powders. Free volumes were determined by means of positron annihilation lifetime spectroscopy (PALS) and molecular weight distributions by means of gel permeation chromatography (GPC). The PALS measurements indicate a decrease of the free volume after short milling times. Prolonged milling, however, results in free volume increase. The changes are irreversible, i.e., they cannot be eliminated by tempering above the glass transition temperature. No dependency was observed on the particle size. The molecular weights decrease continually during milling.