Topic: Controlling Phase Separation with Polymer Networks

Speaker: Dr. Robert Style, ETH Zurich

Time: Thursday, September 5, 2024, 3:30 p.m.

Venue: C511, Main Building, Shahe Campus

Abstract:

Nature has incredible control of phase separation. As a good example, some birds use phase separation to make feathers with vibrant blue colors that arise because they contain highly monodisperse, densely packed air bubbles that have a size around the wavelength of light. The birds must have exquisite control over the size of these bubbles, as even a 10nm change in their diameter will cause the color to change. However, replicating such a process in the lab is extremely difficult, as we must contend with factors such as coalescing of domains and Ostwald ripening, which result in polydisperse materials. I will explain how performing phase separation inside of polymer networks gives us much better control over the phase separation process. This allows us to create large pieces of material with uniform color by phase separating simple components, i.e., without the need for any dye molecules. I will also show how we can also control when and where phase separation occurs by tuning the mechanical properties of the polymer network and talk about how this is relevant to protein phase separation inside living cells.

About the Speaker:

Originally from England, Rob Style got his PhD studying the physics of ice growth at Cambridge University in the UK. He then had postdoctoral positions at Oxford (UK) and Yale (USA) working on freezing and the mechanical properties of soft solids, before taking a post as a Departmental lecturer at Oxford, and subsequently moving to be a Group Leader in the Group of Soft and Living Materials at ETH.

School of Mechanical Engineering and Automation

School of Physics