Stretching the Limits of Ingenuity

Dr. Simon Rondeau-Gagné

Imagine being able to replace a section of damaged spinal cord with a thin, stretchable film that can repair itself.

That’s just one potential application of the research of UWindsor chemistry professor Dr. Simon Rondeau-Gagné, whose focus is smart, wearable, stretchable electronics.

In 2016, Rondeau-Gagné came to UWindsor from Stanford University where he first worked on skin-inspired and stretchable electronics. These materials can be stretched without cracking, so that the tiny transistors embedded within that turn the electrical signals on and off are preserved.

He joined the research team of Dr. Tricia Carmichael, a world-wide expert in surface and materials chemistry. The group has created a 40-nanometre-thin film that looks like transparent rubber for this purpose.

Rondeau-Gagné explains that, “If you want to design wearables, you need to have stretchable transistors, because every time you touch a machine, like your cell phone or computer, every time you ask a machine to do something, it is a transistor that controls the signal.”

A key aspect of the thin film is its ability
 to use heat to heal itself in case of stress. The transistors are typically rigid and cannot tolerate mechanical stress. When stretched, they will crack, stop working, and the machine is broken.

“Once we have a material that is stretchable and robust enough to take repeated use and can self-repair, the potential is whatever industry’s designers can imagine,” DR. SIMON RONDEAU-GAGNE 

The team physically blended very stretchable material that protects the transistor by absorbing the stress of the stretch.

“This is the first time researchers have created a material containing rigid transistors that can be healed,” he says. “Even if it does crack, it can be slowly heated up on a hot plate, and the cracks will heal.”

“Once we have a material that is stretchable and robust enough to take repeated use and can self-repair, the potential is whatever industry’s designers can imagine,” says Rondeau-Gagné.

Health care is a significant area to which the electronics could be applied. “Every biological parameter that needs to be recorded and controlled in real time (blood pressure, brain activity, pulse and frequency) can be monitored through a small, wearable device made from this stretchable film.”

Other medical uses he suggests could be neuron regeneration and monitoring for curing blindness with artificial retina.

Food packaging with smart sensors is another example of technologies that could be highly beneficial to the public. “This technology will integrate sensors to the packaging to detect if the food is fresh and healthy.


“Also, flexible and stretchable transistors could directly be included to the packaging as electronics tags, allowing for a direct and instantaneous check-out for the customers.”

The team used a process called “spin- coating” to create the film. However, 
the researcher expects that such organic electronics technology will eventually be mass produced via roll-to-roll inkjet printing in the future.

In 2016, Rondeau-Gagné co-authored an article in the journal, Nature on the work and earlier this year, the journal Science published his article, “Highly stretchable polymer semiconductor films through the nanoconfinement effect.”

“Smart clothing has already become a reality with sport clothes that can sense your pulse and heart frequency,” says Rondeau-Gagné. “However, I think that the real revolution will happen with smart, fully integrated and multifunctional devices that can be worn on and/or inside a human body.”

He suggests one more possible use for the film: a cell phone that heals itself if it falls on concrete.

Now that could be world-changing.