A Study of the Supercontraction of Major Ampullate Silk by Using a Humidity-Controlled Chamber

10.6567/IFToMM.14TH.WC.PS1.008

Chen-Pan Liao；I-Min Tso；Chung-Lin Wu

Spider silk ； major ampullate silk ； supercontraction ； humidity chamber

Proceedings of the 14th IFToMM World Congress

14th-5（2015 / 11 / 06）

65 - 68

英文

Natural spider silk fiber is composed of a fibrous protein, mixture of crystal, and amorphous secondary structures and also well-known for its excellent mechanical properties such as high strength and extensibility. The feature of major ampullate (MA) silk is one of the strongest spider silk fibers in nature. The MA silks possess the characterization of shrinking by up to 50% when exposed to water. This phenomenon is called supercontraction. In order to realize the mechanical properties of normal MA silk to those of silk under saturated humidity condition (to induce supercontraction), a novel and simple humidity chamber for nano tensile tester was designed and developed in this research. The relative humidity in the chamber can be maintained at greater than at 90% during testing. The measurement results for Cyclosa mulmeinensis spiders showed that mostly tensile properties of supercontracted silk were not significantly different, implying that spiders may adjust the properties of their MA silk by changing the postsecretion process when they inhabited in habitats with different levels of wind distribution.