Scientists have created a substance that can automatically regulate the amount of heat flowing through them, keeping a person cool or warm depending on weather conditions.
When the conditions are warm and moist, such as sweaty body, the fabric lets heat through. As conditions get cooler and drier, the fabric reduces the heat that escapes, researchers said.
University of Maryland researchers in the United States created the fabric from specially developed yarns coated with a conductive metal.
This is the first textile According to the study published in the journal Science, the heat exchange with the environment could be regulated.
Under hot, humid conditions, the yarn strands compress and activate the coating, which changes the interaction of the fabric with the infrared radiation.
They refer to the effect of infrared radiation as "gating", which acts as a tunable shutter for transmitting or blocking heat.
"This is the first technology to dynamically bundle infrared radiation," he told YuHuang Wang, a professor at the University of Maryland.
The basic yarn for this new textile consists of fibers made of two different synthetic materials ̵
This twist brings the yarn strands closer together, opening the pores in the fabric. This has a small cooling effect as heat can escape.
They also alter the electromagnetic coupling between the carbon nanotubes in the coating.
"One can imagine this coupling effect like bending a radio antenna to change the wavelength or frequency with which it resonates," Wang said.
"It's a very straightforward way to think about it, but imagine you're bringing two antennas together to regulate the type of electromagnetic wave they pick up," he said.
"As the fibers are brought closer together, the radiation they interact with interacts, changing in clothing to interact with the heat radiated by the human body," he added.
The tissue either blocks the infrared radiation or lets it pass. The reaction is almost instantaneous, so before the people realize that they are getting hot, the garment may already cool them down.
On the other hand, when a body cools down, the dynamic gate mechanism reverses to retain heat.
"The human body is a perfect cooler, giving off heat quickly," said Min Ouyang, a professor at the University of Maryland.
"For the entire story, the only way to regulate the cooler was to unplug or dress, but this fabric is a true bidirectional regulator," Ouyang