Australian Future Fibres Research and Innovation Centre, Institute for Frontier Materials, Deakin University, VIC 3217, Australia.
Mater Sci Eng C Mater Biol Appl. 2013 Aug 1;33(6):3206-13. doi: 10.1016/j.msec.2013.03.051. Epub 2013 Apr 6.
As a protective shell against environmental damage and attack by natural predators, the silkworm cocoon has outstanding mechanical properties. In particular, this multilayer non-woven composite structure can be exceptionally tough to enhance the chance of survival for silkworms while supporting their metabolic activity. Peel, out-of-plane compression and nano-indentation tests and micro-structure analysis were performed on four types of silkworm cocoon walls (domesticated Bombyx mori, semi-domesticated Antheraea assamensis and wild Antheraea pernyi and Antheraea mylitta silkworm cocoons) to understand the structure and mechanical property relationships. The wild silkworm cocoons were shown to be uniquely tough composite structures. The maximum work-of-fracture for the wild cocoons (A. pernyi and A. mylitta) was approximately 1000 J/m(2), which was almost 10 times the value for the domesticated cocoon (Bombyx mori) and 3~4 times the value for the semi-domesticated cocoon (A. assamensis). Calcium oxalate crystals were found to deposit on the outer surfaces of the semi-domesticated and wild cocoons. They did not show influence in enhancing the interlaminar adhesion between cocoon layers but exhibited much higher hardness than the cocoon pelades.
作为一种抵御环境破坏和天然捕食者攻击的保护壳，蚕茧具有出色的机械性能。特别是，这种多层非织造复合材料结构可以异常坚韧，提高蚕的生存机会，同时支持其代谢活动。对四种类型的蚕茧壁（家养的家蚕、半家养的天蚕和野生的柞蚕、蓖麻蚕蚕茧）进行了剥离、面外压缩和纳米压痕试验以及微观结构分析，以了解结构和机械性能之间的关系。野生蚕茧表现出独特的坚韧复合材料结构。野生茧（柞蚕和蓖麻蚕）的断裂功最大值约为 1000 J/m²，几乎是家养茧（家蚕）的 10 倍，是半家养茧（天蚕）的 3~4 倍。在半家养和野生茧的外表面发现了草酸钙晶体沉积。它们并没有显示出增强茧层之间层间附着力的作用，但表现出比茧皮更高的硬度。
