Dr. Lopez-Pamies will give a talk, entitled
"Understanding & Designing Soft Solids from the Bottom UP: Methods & Applications"

Building Soft solids — that is, solids that are able to undergo large reversible deformations in response to low-intensity stimuli — are used pervasively in commercial applications, and, in recent years, have demonstrated substantial promise to enable new high-end technologies for application in a broad range of fields. Examples include muscle-like actuators, self-repairing structures, and energy harvesters. Almost invariably, these material systems possess complex microstructures (at the micro and nano length scales) which, to a great extent, dictate their mechanical and physical properties. This prompts the need to understand the connection between the underlying microstructure of soft solids and their macroscopic behavior and stability, and how the latter may be enhanced with changes in the former.

In this talk, I will present two theories that permit to describe, explain, and predict the macroscopic behavior of a broad class of soft solids directly in terms of their microscopic behavior. The central idea of the first approach is the construction of “synthetic” microstructures. The idea of the second approach, on the other hand, is based on the development of variational principles utilizing the notion of a “comparison medium”. In addition to providing constitutive models for the macroscopic response, these microscopic theories provide analytical means to investigate the development of (geometric and material) instabilities and therefore the possible onset of failure, a major limiting factor in the design of any material system. Following the presentation of the theories, I will show applications to dielectric elastomer composites and cavitation instabilities.