11 The Magnificence of Spider Silk: Polymer Information

Silk is a protein-based polymer, and one of the only natural filaments. This research has hopes to manufacture spider silk as an alternative to carbon fiber and kevlar, creating a bio-based high strength polymer is very desirable.

Chemical Structure: Spider silk is a protein-based fiber. These proteins are made up of amino acids, primarily glycine and alanine. These amino acids are sequenced in a heavily repeated structure, known as spidroins. They create the core-shell and the nano fishnet structure that gives spider silk its strength. Within the beta sheet nanocrystal there are confined H-bonds that allow for tight packing within the crystalline regions. On the outer region of the beta sheets, there are amorphous chains that link between beta sheets and create an amorphous network that takes up the majority of the space within the silk fibrils.

Types of Spider Silk: Spiders produce two main types of silk, each with their own purposes. The primary type is produced in the major ampullate glands and is known as MA silk or dragline silk. It has to be ready on hand for the spider to escape predators, and it structurally strong. The second type of silk is used to create the spiral of the web, known as flagelliform or flag silk. It is highly elastic, and is designed to dissipate impact energy of prey. Of these, MA silk is more desirable for textile purposes due to its high tensile strength, elasticity, and toughness [4].