Novel Material Uses Flaps To Release And Trap Heat Of Wearer

Jan, 2022 - By SMI

Scientists created a novel material traps heat when it’s dry and releases heat by opening tiny vents when it gets wet with sweat

A group of scientists from Duke University created a new lightweight material that can trap heat when it is dry and releases it when a person starts sweating. The material is made from nylon with a coat of thin layer of silver on one side with rows of small vents to allow the heat to escape. The material uses physics instead of electronic to open these small vents, which makes it potentially useful in different types of clothing in order to keep the wearer comfortable in various situations.

When the inward facing surface of nylon, which is not coated with silver absorbs liquid such as sweat, it gets bloated due to outward curling of the flaps of small vents. When this material get dry the, the nylon shrinks back to its original size and closes the flap. The scientists added this layer of silver with the thickness of 50 nanometer for reflecting body heat back to the wearer, which keeps the wearer warm after the flaps are closed. According to the team, using patches of this material only in parts where people sweat more would be more convenient instead of making a whole garment from the new material.

Furthermore, the team tested the material by making a square of 2.4x2.4in with a few millimeters long flaps. The team found that the new vented patch trapped 16% more heat when the vents were closed and after adding moisture causing it to open the flaps, it was 14% cooler compared to solid patch made from normal polyester blend material. The team is now trying to make the flaps smaller without losing any functionality.