Understanding structure-function-properties relationships in biological and engineered materials

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The development of materials plays an essential role in the modern world. New materials enable new technology. This proposal describes a program of research with a vision of developing deep understanding of the relationships between the structure, function, and properties of natural and engineered materials. We propose to use a powerful family of nuclear magnetic resonance (NMR) techniques, combined with simultaneous mechanical or electrical stimulation, to study the structure and dynamics that underlie the properties of a diverse selection of materials. Specific materials are chosen for their unusual mechanical, optical, transport or magnetic properties, and their potential for industrial applications. NMR is the tool of choice for this work due to its ability to provide site-specific information on the molecular structure and dynamics that underlie these properties. Sea-snails lay their eggs in tough protein capsules that protect the eggs from the harsh marine environment. The little-studied capsule material has an unusual ability to repeatedly dissipate large amounts of mechanical energy. We propose a series of NMR experiments to study the egg capsule protein. We will build new apparatus to apply dynamic mechanical strain synchronized with the NMR measurements. This work will provide an unprecedented microscopic understanding of the fascinating properties, and enable the development of synthetic analogues for applications such as seat-belts and shock absorbers, where strong, energy dissipating materials are required. Celluose nanocrystals (CNC) are an emerging renewable-resource based nanomaterial currently being commercialized by a Canadian company with whom we collaborate. We will use NMR techniques to study the morphology and structure of CNC to guide their optimization and exploitation, and answer fundamental questions about the nature of the crystalline and amorphous components. An unusual feature of CNC is their self-assembly into helically ordered arrays when suspended in water. Other collaborators use these suspensions to make highly-porous ordered glassy films. When filled with active liquid crystal molecules, the optical behaviour of the films can be controlled by external stimulus, potentially to make devices such as displays and sensors. We will study the liquid crystal guests absorbed inside these films to enable the development of practical devices. One of the most important deficiencies with today's lithium batteries is safety. The liquid electrolytes used are flammable and have led to numerous fires and safety recalls. We will work with collaborators to study soy-protein and synthetic polymer-based membranes designed for use as solid electrolytes, with the goal of eliminating the flammable liquids. The techniques we propose, combining applied electric fields with the NMR measurements, will provide a detailed microscopic explanation of the electrical behaviour of these membranes, and will guide the further development of practical solid membranes and safer batteries. The mineral chalcopyrite, in which form most copper is mined, has unusual magnetic resonance properties we will study using our unique multi-photon NMR methods. This work has the potential to transform the processing of copper ores to increase efficiency, resulting in environmental and economic benefits to Canada. The impact of this research will be felt not only within the fields of the individual projects, where our innovative hybrid NMR methods will provide unparalleled new insights into molecular mechanisms, but also from the synthesis of the results; by learning from the common themes and unique differences of these materials, we will both broaden and deepen our understanding to accelerate the advancement of our materials-driven world.