The team at Stanford University’s Bao Lab created a flexible electrode that uses a molecule often found in soup thickeners. This flexible electronic material performs at a fast rate even when stretched out (Image via Stanford University)
When you think about electronics, “stretchy” isn’t the first thing that comes to mind. Usually, electronics are hard, cold, and brittle. One team from Stanford University’s Bao Lab is looking to change things. The team created an electrode that’s flexible and has high performance. The device is almost transparent and kind of looks like those second skin bandages. So how did they do it? By using a soup thickener.
That’s not a joke. The new stretchy material uses a molecule normally used to thicken soups to help make it more flexible. When the team mixed two different polymers for insulators, they found it conducted well but wasn’t all that flexible. Instead, it was brittle and would break if stretched out just 5 percent of its original length. To fix this, they had the SLAC National Accelerator Laboratory use their special x-ray equipment to find the right additive to produce the results they wanted. It’s a finicky task – adding materials to a conductor often weakens its ability to transmit signals. After testing 20 different additives, they landed on the right one, a molecule similar to that in soup thickeners. When added to the polymers, it stopped the crystallization process and gave the electrode its stretchy effect.
Not only is the material flexible, it actually conducts electricity better when it’s stretched out. Its high conductivity and 96 percent light transmittance are the “highest values reported for…transparent electrodes” and the best for a flexible material overall, according to the team. Right now the material is still in the prototype stages, but the results so far look promising. The team will keep working on it as part of their long-term focus on making flexible material s that make contact with the human body.
The possibilities for this electric material are endless. The team have already created electrodes and stretchable transistor arrays using an inkjet printer. They hope to use it for brain interfaces and “other implantable electronics.” It could make great strides in brain monitoring and other complex medical procedures. Outside of the medical field, it can also be used to improve smart clothing equipped with heat sensors, LEDs, and other abilities. Imagine, smart clothing that’s not only efficient, but comfortable. You wouldn’t have to worry about making awkward movements to avoid breaking the tech. It’s a great development that makes you question what other items in your pantry can be used for science.
For the record, this isn't the first stretchable or wearable electronic development I've covered here. See these: One, two, three, four.
Have a story tip? Message me at: cabe(at)element14(dot)com
