CHAPTER 14. Mussel Byssus Fibres: A Tough Biopolymer

Byssus fibres are tough biopolymer fibres produced by mussels to attach themselves to rocks. Byssus fibres have been extensively studied, mainly due to two remarkable properties: their extraordinary capability to remain adhered to hard surfaces in aquatic habitats, and their high strength and extensibility that allow them to withstand the large and repetitive force produced by waves, with velocities of over 10ms−1 and accelerations of approximately 400ms−2. Byssus fibres are composed mainly of proteins that are assembled to form a specific hierarchical and biological structure. In this chapter the main characteristics and properties of mussel byssus with regard to their potential applications are discussed. After a brief introduction of the natural history of mussels, three different aspects of byssus are covered. First, the structure of byssus fibres at different levels, including chemical composition and morphology, are described. Then, the structural, mechanical, thermal and adhesive properties of byssal threads are reviewed and discussed. The last section includes a more detailed account of their biomechanical and adhesive properties for applications in medicine and biotechnology. All these aspects are finally assessed with regard to the potential use of mussel byssus as a source of inspiration for the design of novel biomimetic polymers and composites.