Engineers inspired by marine creatures have made a fabric that adjusts to your body heat and keeps you at a temperature of your choosing. Better yet, it is breathable and washable.
The US-based team say their fabric could be used in athletic apparel, food packaging, infrared camouflage, soft robotics and biomedical sensing.
Their research is published in APL Bioengineering.
Bioengineering is a field that takes inspiration from nature and adapts it into new products by applying engineering design principles. In this case, the team were inspired by the colour-changing abilities of squid.
“Squid skin is complex, consisting of multiple layers that work together to manipulate light and change the animal’s overall coloration,” says senior author Alon Gorodetsky.
Gorodetsky and colleagues observed how squid change colour by flexing and relaxing muscles under their skin.
“Some of the [skin] layers contain organs called chromatophores, which transition between expanded and contracted states (upon muscle action) to change how the skin transmits and reflects visible light,” says Gorodetsky.
The team designed a composite material with chromatophore-like copper islands. Stretching the material separates the islands and changes how they interact with light.
Instead of changing visible light, the team’s material modifies infrared light.
As people warm up, they emit some of their heat as invisible infrared radiation. The team’s new material can adjust how much of this infrared radiation is lost and how much is reflected back to the wearer.
The next challenge was making the composite material functional by integrating it into a mesh-like fabric as well as making it washable and breathable.
To make it washable, they added a thin film that allowed the fabric to be washed many times without degrading.
To make it breathable, the team perforated the fabric so it acted like cotton in the presence of air and water.
To ensure that the new fabric could still dynamically adjust to heat, the team tested it on a sweating guarded hot plate – a device that emulates the temperature and moisture of human skin. They found that their new fabric performed well.
“Our advanced composite material now opens opportunities for most wearable applications but may be particularly suited for cold weather clothing like ski jackets, thermal socks, insulated gloves, and winter hats,” says Gorodetsky.
The Ultramarine project – focussing on research and innovation in our marine environments – is supported by Minderoo Foundation.