Polar bears are one of the most well-known animals of the Arctic, most likely due to their bright white fur (which actually is not white). These mammals are the largest living carnivores on land and can withstand temperatures as low as -50 degrees Fahrenheit. In order to stay warm, polar bears have a thick layer of blubber and two layers of fur, which traps the majority of their heat inside of their body. While they appear to be white, polar bears actually have colorless fur that reflects visible light overtop of black skin1.
Engineers have spent decades investigating the fur of polar bears to determine a way to manufacture a textile that would have very similar properties. Three engineers from the University of Massachusetts Amherst have completed just that. Trisha L. Andrew, an associate professor of chemistry and adjunct in chemical engineering at UMass Amherst, and her team discovered that a polar bear’s fur “is extremely effective at transmitting solar radiation toward the bears” and does an excellent job at keeping that heat inside of the body2.
Knowing this key detail, Andrew and her team were able to develop a bilayer fabric; the top layer is composed of threads that conduct visible light down to the deeper layer, which is made up of nylon coated in PEDOT. PEDOT, or more specifically PEDOT:PSS (poly(3,4-ethylenedioxythiophene):polystyrene sulfonate), is a flexible transparent material that is also conductive3. PEDOT chemical is typically used for low-cost printed electronics, optoelectronics, and polymeric solar cells. It is composed of two ionomers that form a macromolecular salt4.
The bilayer fabric allows for a jacket to be made that is 30% lighter than a similar jacket made from cotton, while keeping the internal temperature the same at temperatures reaching 10℃ lower. The only stipulation is that there needs to be a presence of sunlight or the light from a well-lit room to ensure full functionality of the jacket.
So I guess the newest winter trend will be styling ourselves after polar bears?
Your title and opening picture are very effective. The notion of learning from nature is always appealing, and learning how to keep warm from polar bears is particularly appealing. It adds to a positive picture of chemistry and chemists. Science Daily is not the most widely read source nor is it a general interest source, but the harper collins blog for kids is a plus. Your lede paragraph is catchy and quite concise. Your explanation of the engineered material is also quite concise and probably reasonably comprehensible to a general reader. I expect that the poly thiophene is protonated to form a salt with the polystyrene sulfonate. Overall a timely and effective post.
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