Engineers at the University of Massachusetts Amherst have created a synthetic textile modeled on polar bear fur. The team has founded a spin-off company, Soliyarn, LLC, and has begun production of the cloth.
Researchers have long questioned exactly how a polar bear’s fur aids them in surviving in temperatures as low as -50 C in the Arctic. Though we would expect the answer to be insulation by the fur, it was discovered that the bears’ coat actively uses sunlight to maintain their temperature.
“But the fur is only half the equation,” says the paper’s senior author, Trisha L. Andrew. “The other half is the polar bears’ black skin.”
Polar bear fur is essentially a natural fiber optic, which can conduct sunlight down to the bears’ skin, which absorbs the light, raising the bears’ body temperature. The fur is also exceptionally good at preventing the warmed skin from emitting the warmth it contains.
Based on this, the team engineered a bilayer fabric whose top layer is composed of threads that act fiber optically – just like polar bear fur – conducting visible light down to the lower layer, which is made of nylon and coated with a dark material called PEDOT. PEDOT, like the polar bears’ dark skin, warms efficiently.
They found that a jacket made of such material is 30% lighter than the same jacket made of cotton, yet is able to keep a person comfortable at temperatures 10 degrees Celsius colder than the cotton jacket could, as long as there is sunshine or a well lit room.
“Space heating consumes huge amounts of energy that is mostly fossil fuel-derived,” says Wesley Viola, the paper’s lead author. “While our textile really shines as outerwear on sunny days, the light-heat trapping structure works efficiently enough to imagine using existing indoor lighting to directly heat the body. By focusing energy resources on the ‘personal climate’ around the body, this approach could be far more sustainable than the status quo.”