Paper number 497
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BIODEGRADABLE POLYESTER MATRIX REINFORCED WITH HEMP FIBRES - EFFECT OF FIBRE REFINEMENT BY STEAM EXPLOSION |
A. Keller1, H. Zerlik2, E. Wintermantel2
1 Swiss Federal Research Station for Agricultural Economics and Engineering,
CH-8356 Taenikon, Switzerland
2 ETH Zurich, Biocompatible Materials Science and Engineering, Wagistrasse 23, CH-8952 Schlieren, Switzerland
| Summary | A biodegradable copolyester was compounded in a twinscrew extruder with 25 wt% hemp fibres and then injection moulded into tensile test bars. Two different types of fibres were used: An exclusively mechanically treated fibre (MEC) and a fibre refined by steam explosion (STE). The mechanical properties of STE fibres are 30 % lower than those of MEC fibres, nevertheless the same reinforcing effect was obtained. This is mainly due to the higher aspect ratio of STE and the better fibre distribution in the STE composites. A maximal reinforcement was not achieved, because of a too weak fibre matrix adhesion in combination with an insufficient fibre length caused by fibre damage in the extrusion and injection moulding process. |
Keywords | biodegradable, copolyester, steam explosion, hemp fibre. |