Abstract: This talk will describe efforts in our research group to control the shape and function of soft materials (liquid metals, polymers and hydrogels) for applications that include stretchable electronics, soft robotics, and self-folding polymer sheets. The research harnesses interfacial phenomena, micro fabrication, patterning, and thin films. The talk will discuss two topics:
Gallium-based liquid metals have low-viscosity, low-toxicity, and can be patterned due to a thin, oxide skin that forms rapidly on its surface. It is possible to pattern the metal by injection into microchannels or by direct-write 3D printing to form ultra-stretchable wires, deformable antennas, and microelectrodes. It is also possible to remove / deposit the oxide using electrochemistry to manipulate the surface tension of the metal over unprecedented ranges and thereby control the shape and position of the metal for shape reconfigurable devices.
Self-folding polymers sheets that change shape in response to light. These sheets are a form of shape memory polymers that are compatible with 2D patterning techniques including lithography, inkjet printing, and roll to roll processing. The appeal of this work is converting 2D patterns into 3D shapes (similar to origami) in a hands free manner.