Dresden 2003 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
CPP: Chemische Physik und Polymerphysik
CPP 21: POSTER B
CPP 21.3: Poster
Dienstag, 25. März 2003, 19:00–21:00, ZEU/250
Native cellulose fibres under tensile stress — •Claas Behrend1, Klaas Kölln1, Ingo Grotkopp1, Christian Riekel2, Sergio S. Funari3, and Martin Müller1 — 1Institut für Experimentelle und Angewandte Physik, Olshausenstr. 40, D–24098 Kiel — 2ESRF, BP 220, F–38043 Grenoble Cedex, France — 3MPI-KGF c/o HASYLAB at DESY, Notkestr. 85, D–22603 Hamburg
Cellulose is the most abundant structural biopolymer found on earth. The crystalline structure of cellulose itself is well known. On the contrary, there are still open questions on the morphology and the mechanical properties of cellulose as a composite material.
We investigated the tensile properties of flax cellulose fibres using microfocus wide-angle X-ray diffraction (WAXS) at the ESRF (ID13) and standard WAXS at HASYLAB (A2). Single flax fibres and small bundles of flax fibres were mounted in a stretching device. Tensile load was applied along the fibre direction with a constant stretching rate. The simultaneous measurement of the displacement of the jaws and the force yield a stress–strain curve of the entire fibre. In addition, the stress–strain relationship for the crystalline parts can be monitored by the change in lattice spacing using the recorded WAXS patterns. Assuming an isotropic distribution of the stress within the composite material, Young’s modulus can be calculated for the entire fibre as well as for the crystalline parts. Furthermore parameters such as microfibril angle and crystallinity could be deduced, thus leading to a better understanding of the morphology of cellulose.