THE EFFECT OF DEGRADATION ON THE MECHANICAL PROPERTIES OF BIODEGRADABLE POLYLACTIDE YARNS AND TEXTILES

A large research effort worldwide is directed at reproducing 3D tissue and one recent development in the production of tissue engineering scaffolds is the use of biodegradable materials. This research investigates the possibility of producing biodegradable knitted scaffolds from poly lactic acid yarns. Degradation in the following biodegradable yarns is studied and the effect on their mechanical properties determined: a commercial polylactide (PLA) yarn Lactron (Kanebo Gohsen Ltd) and four yarns extruded in the Biomedical Textiles Research Centre (BTRC) from a medical grade Poly (L-lactide) (PLLA) polymer (purac biochem). To determine the degradation effects the mechanical properties were evaluated on a Nene tensile testing rig and samples observed under the scanning electron microscope; before and after the yarns were immersed in phosphate buffer solution (pH=7.4) for various lengths of time at 37°C. The yarns extruded in-house showed a gradual decline in tenacity over the degradation period, unlike the commercial yarn where the tenacity was maintained. This work shows that the degradation process is affected by factors such as extrusion speed and twist. With further knowledge, it may be possible to produce polylactic acid yarns with known degradation and cell attachment characteristics for textile tissue engineering scaffolds. In conclusion, polylactic acid yarns have good potential and biodegradable textile tissue engineering scaffolds look promising for the future.