Flexibility and Form: Emergence of Shape in Thin Sheets

Nov 17, 2021, 4:00 pm5:00 pm
Engineering QUAD, A224
Event Description

Thin sheets assume a rich diversity of shapes in the natural world, ranging from folds on the earth’s crust, to the wavy shapes of leaves and flowers, down to more microscopic biomembranes and synthetic thin films. These patterns are made up of smooth architectural motifs such as wrinkles, as well as focused localized objects such as folds and ridges. Our experiments study the emergence of complex shapes in thin, fluid-supported polymer films starting from simple featureless initial conditions via successive elastic instabilities. Understanding these patterns required new notions of ‘thinness’ or bendability, which define regimes in which textbook theories of post-buckling behavior are no longer useful. I will start the talk by describing the basics of adsorption of a thin film at a flat fluid interface, discuss some representative pattern-forming scenarios, and end by describing new opportunities for wrapping and encapsulation with highly-bendable materials.