Researchers have developed a smart material that allows heat to escape through tiny openings when the body starts sweating.
Duke University experts created the innovative technology. The vents then shut again to preserve heat after drying.
According to US researchers, the lightweight material relies on physical forces rather than electronic devices to open vents. This makes it a viable option for putting in patches to various kinds of clothing.
Scientists have created a new material which opens tiny vents that allow heat to escape from the skin when it starts sweating. Duke University experts created this innovation to let heat escape when a person starts sweating. The vents then shut down again once the material is dry.
Experts at Duke University developed the innovation. Once they have dried, they close again to keep heat in.
Po-Chun Hsu assistant professor of mechanical engineering at Duke said that layers are necessary for people who ski or hike in colder climates. This allows them to adjust the heat they trap as their bodies heat up.
“But, by strategically placing pockets of a material capable of letting out heat when someone is sweating it can be made into a one-piece textile.
Hsu’s team has not revealed the price of these patches or their manufacturing costs.
He chose to make the part from nylon as it was inexpensive and lightweight. It also curls up if it’s exposed to water.
However, it’s not well-known for its ability to make warm clothing. Hsu therefore added an additional layer of heat-trapping copper on top.
He expected that the weight of silver would bog down his nylon flaps, but it turned out to make them curl even further.
After experimenting with various thicknesses of silver, Hsu settled on a size of around 50 nanometers — 2,000 times thinner than a sheet of paper.
Cate Brinson also of Duke said, “It’s amazing and counterintuitive that adding something heavy to a polymer could actually bend it and open more,”
“It boils down that the silver shrinks while the nylon expands.
She said that nylon’s bottom layer expands when wet.
It can’t, however, stretch because of its attachment to the silver. Therefore, the best option for this material is to curl up and allow the nylon to expand, while the silver shrinks.
In the experiments, the researchers created a patch about the size of a human hand with flaps a few millimeters long — about the size of a fingernail.
Compared with an average traditional textile represented by a blend of polyester and spandex, the material is about 16 per cent warmer when dry with the flaps closed and 14 per cent cooler when humid with the flaps open.
Researchers said that the combination of the nylon and silver hybrid could increase the thermal comfort area by 30%.
Hsu and his colleagues haven’t yet revealed the commercial price of the materials or how expensive they would cost to produce.
But he preferred nylon as the dual-purpose material. Nylon is lightweight, inexpensive and very soft. If cut in flaps, it will curl up on its own when it comes to being exposed to water.
Hsu claims that this strategy has many advantages over existing ways of venting heat through warm clothes, such as putting zippers underneath the armpits.
He stated, “We want to vent the sweating areas of our body, but not necessarily the underarms.”
“Our chest and back require more ventilation, but it is nearly the same effort as taking off clothing to open these zippers, if they are available.
Hsu is currently working to reduce the size of vents while maintaining their effectiveness. A top nanocomposite layer is another option that Hsu has been exploring. This could allow the material to be any colour it wants without altering its thermal characteristics.
Hsu stated, “I believe that we can achieve this effect without appearing to be wearing costumes if we find the best laser cutting method to make very small flaps on clothing and attach them to the patches.”
“With enough effort, this type of material could very closely look like what we are wearing now.”
Science Advances has published this research.
Scientists have created a wearable, thin strip of electricity that can generate electricity as your sweat evaporates while you sleep
The developers of a new device wrap around the finger and acts as a plaster to collect sweat from your fingers while you’re asleep. It can then be used to produce electricity.
The developers of the new wearable device claim that it wraps around your finger as a plaster to collect sweat and generate electricity.
At the moment the prototype has only a tiny amount of power. It would require approximately three weeks of continuous wear to charge a smartphone. However, developers at University of California San Diego hope to improve the device’s capacity.
It was found that a watch worn for 10 hours could generate sufficient power for it to last 24 hours, or 400 millijoules.
It’s just one fingertip. Researchers found that securing devices to the other end of your fingertips could generate 10x more energy.
Many power-generating wearable devices will require users to do vigorous exercise or rely on outside sources like sunlight or temperature swings.
The team explained that the new strip is based on a passive system, which generates electricity even when you’re asleep or sitting still.
Because the fingertips are among the most sweaty parts of the body it is important to collect this material and have conductors process it.