Many naturally occurring macromolecules and colloids take the shape of rigid rods. These include some proteins, DNA, plant viruses, certain clay minerals, and even (if we are broad-minded about it) some bacteria. A number of synthetic mimics, ranging from synthetic polypeptides to gold nanorods, carbon nanotubes and PRINT particles, can provide various high-performance materials based on polymeric liquid crystals or simpler phases. Compared to other shapes, rods span a great distance per unit mass. As a result, they easily interact with each other. Dilute solution behavior is only guaranteed when the systems are really dilute. At practical concentrations for processing, behavior is complicated. The greater the complications, the greater the need for simple, well-behaved systems. In this talk, several emerging model systems for will be discussed. These will include cellulose nanowhiskers, a “perfect polypeptide” (uh-oh!), and some highly unusual bubbles and blobs arising from fungal proteins. Some of these systems, in addition to new serving as model rods, offer the potential for unusual applications too. For example, it is possible to contemplate liquid crystals made mostly of air.
Andrew Lyon 404-894-8222