Researchers make breakthrough discovery in stretchable electronics materials

By using the elasticity of polymers such as

a

silicone, these emerging technologies are made to move in ways that mimic skin.

This sheds light on why Smooth-On Ecoflex, a substance most commercially used to create molds and movie masks and prosthetics, is the most prominent silicone elastomer (a rubber-like substance) found in research.

While handling a sample of the material, Dr. Matt Pharr, assistant professor in the J. Mike Walker '66 Department of Mechanical Engineering at Texas A&M University, and graduate student Seunghyun Lee, recently discovered a new type of fracture.

"I have done some work in the area of stretchable electronics, so I have a lot of materials from when I was a postdoc. We had to store samples in our office and, likewise, I had some here because we were going to use them in a project that we ended up not doing. I'm a nervous fidgeter and while I was playing with it, I noticed something weird," said Pharr.

This oddity is what Pharr and Lee refer to in their recent publication "Sideways and Stable Crack Propagation in a Silicone Elastomer" as sideways cracking. This phenomenon is when a fracture branches from a crack tip and extends perpendicular to the original tear.

https://phys.org/news/2019-05-breakthrough-discovery-stretchable-electronics-materials.html