Electrically heated clothing designed to prevent frostbite during cold weather
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Researchers at the University of Massachusetts (UMass) at Amherst have made used of a standard chemical technique to create electrically heated material that can be woven and sewn into comfortable clothing, including gloves.
The team used vapour deposition in order to produce a thin film. For years, textiles scientists have avoided using this method to develop commercial products, due to the technique being too complex and costly to scale up from a laboratory setting. It is now becoming affordable enough to use in marketable products.
By depositing a nanocoating of a conducting polymer called PEDOT onto threads of cotton yard often used to make knitted jumpers, the UMass team were able to weave soft, flexible material that can be electrically heated and sewn into clothing.
To test their material, they turned it into a heated glove which could be used to provide extra protection against frostbite.
“We took a pair of cotton gloves and coated the fingers to allow a small amount of current to pass through, so they heat up,” said Professor Trisha Andrew, who led the research. “It’s regular old-fashioned cotton cloth. We chose to make a pair of gloves because the fingers require a high curvature that allows us to show that our material is really flexible.”
“One thing that motivated us to make this product is that we could get the flexibility, the nice soft feel, while at the same time it’s heated but not making you sweaty. A common thing we hear from commuters is that in the winter, they would love to have warmer fingers,” she added.
In a test, the researchers found that the fingers of the test glove warmed the wearer’s fingers to the same temperature as the palm and continued to work for eight hours before requiring recharging. This could, in particular, help those who have to work under cold conditions, such as during outdoor night shifts.
The glove has three layers, with the PEDOT-coated layer covered in insulating material and never coming into contact with the skin. It is powered with a small button battery weighing less than a penny and running on nanoAmps: too small a current to cause painful electric shocks.
“Lightweight, breathable and body-conformable electrical heaters have the potential to change traditional approaches to personal thermal management, medical heat therapy, joint pain relief and athletic rehabilitation,” the researchers wrote in Applied Materials & Interfaces.
Professor Andrew says that it is the most “consumer-ready” device they have and hopes that the material could reach the market in five years.