U of A researcher developing e-textiles to transform medical and safety fields
Imagine a wound dressing that changes colour to let you know if your cut is infected. Imagine a T-shirt that tells athletes they’re dehydrated or one that monitors blood sugar levels for diabetes patients.
Imagine a coverall that would alert workers to contamination levels and danger levels in real-time.
“There is a lot of research around e-textiles,” says Hyun-Joong Chung, an assistant professor in the Department of Chemical & Materials Engineering at the University of Alberta. “I have always been most interested in developing wearable electronics for the biomedical sector to help society.”
Chung is a materials engineer, and his research mostly involves the development of a gel-like polymer that can be used as a conduit or sensor for wearable devices and in energy storage.
Polymers can be found in nature — such as wool, cotton, silk and even your DNA — or be synthetic — like polyester, nylon and neoprene — and in simple terms, are chemical compounds where molecules are bonded together in a chain of many repeating units.
Chung did his PhD training in polymer science and then worked for three years with Samsung Displays in Korea, where he was involved in the development of OLED TVs and flexible electronics. He then did postdoctoral research on stretchable electronics, and now combines that knowledge with his background as a materials engineer to focus on developing wearable electronics.
Fabrics are inherently “smart materials” with their unique and various characteristics for skin comfort, says Chung. For e-textiles, flexible and stretchable electronics for sending and receiving information are incorporated into the fabric without affecting garment comfort. Recent advancements in nanotechnology and stretchable electronics is what is driving much of the current research.
“There have been so many promises that could not be kept since the 1980s. However, in the 2010s, the promises are really approaching reality with maturing development of nanotechnology,” he says. “Chips are made small enough to be distributed over large areas of the textile. Textile-like wires are woven into the fabric, seamlessly connecting the chips.” Chung’s focus is on developing those flexible wires, which can be embedded or printed on fabric. “Stretchability is key.”
Chung is presenting Nov. 6 at the Davey Protective Clothing Systems for Safety Seminar on the history of e-textiles, current market challenges, and the research from his Soft Material and Device Lab at the U of A.
In his research on smart wound dressings, for example, the hydrogels in the patch measure the pH level of your skin and change colour to indicate whether the cut is infected or not.
His team is also working with psychologists and rehabilitation researchers around measuring brain waves in EEGs and EMGs.
“Currently, they have to shave a patient’s head a little, or apply a lot of gel, to make the area more conductive. With a good e-textile, very thin, you don’t have to shave at all,” says Chung. The product he’s working on looks like a Tegaderm dressing.
Chung sees many applications for the safety field involving sensors, including the detection of human movement.
“Wearable devices can monitor posture and the force to the body in a precise way, in a very non-intrusive way,” he says. “That information can be collected centrally or by the worker himself.”
The e-textiles could also be chemically functionalized, for example, to measure poisonous substances in order to provide workers with instant notifications of dangerous levels of exposure.
“Those devices are available now, they are just too cumbersome. If it can be just like a textile, the user will wear it to pick up those danger signs.”
Chung and other researchers of smart textiles are aiming for the development of inexpensive, mass produced e-textiles. “It’s a very open field.” Two elements are key to finding success.
“First, is finding a material that is conductive without using noble metals like gold or silver. They are too expensive. If we can use conductive polymers or carbonaceous materials it will be much cheaper,” he says.
And secondly, “3-D printing to allow for custom shapes and products at a less expensive price. If you can print electronic wires that are thin enough and robust enough, you will have an e-textile.”
There are a few e-textiles already entering the marketplace, and more will quickly follow.
“Any product will breakthrough any minute now,” says Chung.
“Everyone is looking to find the sweet spot between price and necessity.”
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Barb Wilkinson is a freelance writer and editor based in Edmonton.
