Target audience: Chemists, biologists, who have an interest in the mechanics aspects of biological materials & structures.
Most natural (or biological) materials are complex composites whose mechanical properties are often outstanding, considering the weak constituents from which they are assembled. These complex structures, which have risen from hundreds of millions years of evolution, are inspiring Materials Scientists in the design of novel materials. Their defining characteristics, hierarchy, multifunctionality, and self-healing capability, are illustrated. Self-organization is also a fundamental feature of many biological materials and the manner by which the structures are assembled from the molecular level up. The basic building blocks are described, starting with the amino acids and proceeding to polypeptides, polysaccharides, and polypeptides saccharides. These, on their turn, compose the basic proteins, which are the primary constituents of soft tissues and are also present in most biominerals. We describe only the principal protein types, with emphasis on collagen, chitin, keratin, and elastin The hard phases are primarily strengthened by minerals, which nucleate and grow in a biomediated environment that determines the size, shape and distribution of individual crystals. The most important mineral phases are discussed: hydroxyapatite, silica, and aragonite. The principal mechanical characteristics and structures of biological ceramics, polymer composites, elastomers, and cellular materials are presented. Selected systems in each class are described with emphasis on the relationship between their structure and mechanical response. A fifth class is added to this: functional biological materials, which have a structure developed for a specific function: adhesion, optical properties, etc An outgrowth of this effort is the search for bioinspired materials and structures.
Grading will be given in two stages: (1) Weekly exercises; (2) either a short (15 min) presentation by every student on a specific topic selected by the student from a list proposed by the teacher; or a written exam.