The difference in tensile behaviour of different silks of the spider A. diadematus

摘要

During recent years, spider silk has attracted the interest of a lot of scientists because spider silk, and in particular the "dragline" thread, is a fibre with a unique combination of high tensile strength, high strain and an ultra-low weight. In order to help explain the structure-property relationship of spider silk, the tensile behaviour of both dragline and cocoon silk of A. diadematus is compared. Although their breaking strain is almost the same, the stress-strain behaviour of both spider silks is completely different. Moreover, the influence of the testing speed is discussed. In the case of cocoon spider silk, the testing speed has a statistically significant influence on the measured tensile properties, especially on tenacity, and on initial and post-moduli. For draglines, no statistically significant influence of speed on the measured properties could be found, probably because of the high variability between and within samples. It is also observed that the filaments constituting the dragline can show different tensile behaviour. Further research on the microstructure of both spider silks should help revealing the secrets of nature and could open new ways for the production of environmentally friendly biopolymers.