Title: Mechanical properties of confined mussel-inspired materials
There is currently a need for improved adhesives for medical and marine applications, primarily because the presence of water severely undermines adhesion. Due to their robust adhesion under water, marine mussels have been widely studied as inspirations for the design of wet adhesives. However, development of mussel-inspired materials has historically over-emphasized the importance of the catechol functionality in mussel adhesion. This thesis demonstrates that the mechanical properties of mussel-inspired materials, including adhesion, cohesion, and stiffness, result from a range of factors beyond the presence of catechols. By investigating model systems spanning multiple length scales, this work reveals the importance of failure mode, binding group density, and electrostatic interactions on interfacial adhesion of mussel-inspired surface primers and peptides at the atomic scale. Interactions between thin films of pressure sensitive adhesives and polymers are shown to depend on film composition which is influenced by solvent-induced structural rearrangement and contact-induced damage. The mechanical properties of micro-scale hydrogel films are shown to be dictated by fluid flow through the polymer network. By providing a better understanding of mussel adhesion, this work seeks to guide the design of new mussel-inspired materials for diverse applications.