DYNAMIC CHARACTERISATION OF BIOPOLYMER FIBRES USING AN ENVIRONMENTAL SCANNING ELECTRON MICROSCOPE

摘要

Biopolymer fibres are generally recognised to be one of the most dynamic and promising materials for biomedical and other applications. The use of new tools is vital in the fundamental and practical research of these versatile fibres. Environmental Scanning Electron Microscope (ESEM) is a low vacuum analytical technique, which allows for dynamic experiments at a range of pressures, temperatures and under a variety of gases/fluids. In this study, a Phillips XL-30 FEG-ESEM was used to characterise the biopolymer fibres of poly(L-lactic acid) and alginate under dynamic conditions. Dynamic wetting and absorption of the fibres were examined in situ by providing conditions in favour of condensation or evaporation of water. A full energy dispersive x-ray analysis (EDX) mounted on the ESEM was also used to detect the ion exchange behaviour of the alginate fibres. A mechanical testing stage was placed in the ESEM chamber to examine the dynamic tensile properties of the biopolymer fibres. The ability of ESEM to follow dynamic events has given new insight into the kinetics of structure rearrangement and breakdown of the biopolymer fibres under dynamic conditions. The study has also revealed that the ESEM is a promising tool in the dynamic studies of textile materials.