CPOS SEMINAR: "Tailoring functional properties in polymer composites and multi-materials via macromolecular design"
Speaker: Divya J Iyer, PhD, Elings Postdoctoral Scholar, Materials Department - Bates Group, UCSB
Biology is replete with examples of composites and multi-materials (e.g., nacre, bones) known for their robustness, strength, and functionality. These properties are attributed to their stiffness mismatch and precise hierarchical structure. Over the years, synthetic polymers and composites, owing to their versatility, have garnered interest as mimics for these natural systems. Gaining inspiration from these robust biological systems, this presentation will discuss the facile design of covalently linked polymer composites and multi-materials.
The first part of this talk will discuss the development of covalently linked organic-inorganic composites comprising (i) products from the chemolysis of polyurethane foam, and (ii) naturally occurring aluminosilicate particles. The covalent linkages between the organic polyurethane component and the inorganic naturally occurring aluminosilicate particles will be shown to result in lightweight composites with flexural strengths comparable to common building materials (e.g., cement). The influence of the chemistry and composition of the macromolecular network on the density, strength, and microstructure of these composites will be discussed. Finally, the unique failure patterns of these composites will be elucidated by a detailed microstructural analysis.
The second part of this talk will discuss the design and 3D printing of multi-materials with spatially controlled stiffness via digital light processing. The role of polymer chemistry and the extent of network formation on the spatial stiffness contrast in these materials will be presented. This work leverages the light-responsiveness of monomers to 3D print bio-inspired materials with precise hierarchical structures.
The two sections of this talk are unified by their design and inspiration, yet distinguished by their chemistry, governing principles, and applications.
