Spider web silk

Tensile strength as for spider web, silk, flax, sisal. 

Spider-web silk is ca. five times stronger than steel by weight, and almost as elastic as nylon. Fibers comprised of the synthetic silk were demonstrated to be stronger than Kevlar, and may be useful for biomedical applications such as artificial tendons and ligaments and surgery sutures, as well as lightweight body armor for military applications. 

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