Biomimetic materials

Biological materials present the conventional materials scientist with alternative ways of achieving durability, recyclability, and adaptability. Technical materials are commonly designed to resist the initiation of cracks; biological materials control disaster by initiating failure where it can be more closely controlled and the strain energy can be more easily absorbed, at the same time controlling shape so that stress concentrations are avoided in sensitive areas. Most materials are hydrated and soft, achieving stiffness by dehydration and mineralization. The low energy of the predominant hydrogen bonds allows relatively easy breakdown and recycling of the units of biological materials. Since most biological materials are metabolically accessible (obvious exceptions are keratins and wood) they can be recycled and repaired in situ, adapting the organism to changing circumstances internally and externally. At the molecular level, liquid crystallinity is a driving force.