Biomimetic Materials by Freeze Casting
Prof. Ulrike Wegst, Thayer School of Engineering at Dartmouth
The skilled use of biological materials and their striking mechanical efficiency have played a key role in the development of mankind and technology, and the course of history. The considerable advantage that we have over our ancestors, today, is that we cannot only successfully apply and use biological materials in their "native" state, but that we have tools to investigate and test them at almost all levels of their structural hierarchy to identify principles of function and optimization. Important challenges that persist are both the design of synthetic materials that mimic the performance-defining features of their natural counterparts and their fabrication in bulk with a fast and easy production process. One manufacturing process that shows promise is freeze casting; it offers a relatively fast route for self-assembled structures with complex architectures, whose hierarchical structures span dimensions from the nano- to the macroscale. Reviewed in this presentation will be the large range of polymer, ceramic, metal and hybrid materials, which can be prepared by freeze casting. Described will be the mechanisms that drive structure formation during processing and how these can be employed for the material’s structural and property optimization for applications that range from tissue scaffolds to filtration, and energy generation and storage.