For polar bears, the insulation provided by their fat, skin, and fur is a matter of survival in the frigid Arctic. For engineers, polar bear hair is a dream template for synthetic materials that might lock in heat just as well as the natural version. Now, materials scientists in China have developed such an insulator, reproducing the structure of individual polar bear hairs while scaling toward a material composed of many hairs for real-world applications in the architecture and aerospace sectors.
Their work appears June 6 in the journal Chem.
“Polar bear hair has been evolutionarily optimized to help prevent heat loss in cold and humid conditions, which makes it an excellent model for a synthetic heat insulator,” says co-senior author Shu-Hong Yu, a professor of chemistry at the University of Science and Technology of China (USTC). “By making tube aerogel out of carbon tubes, we can design an analogous elastic and lightweight material that traps heat without degrading noticeably over its lifetime.”
Unlike the hairs of humans or other mammals, polar bear hairs are hollow. Zoomed in under a microscope, each one has a long, cylindrical core punched straight through its center. The shapes and spacing of these cavities have long been known to be responsible for their distinctive white coats. But they also are the source of remarkable heat-holding capacity, water resistance, and stretchiness, all desirable properties to imitate in a thermal insulator.
“The hollow centers limit the movement of heat and also make the individual hairs lightweight, which is one of the most outstanding advantages in materials science,” says Jian-Wei Liu, an associate professor at USTC. To emulate this structure and scale it to a practical size, the research team–additionally co-led by Yong Ni, a mechanical engineering professor at USTC–manufactured millions of hollowed-out carbon tubes, each equivalent to a single strand of hair, and wound them into a spaghetti-like aerogel block.
Compared to other aerogels and insulation components, they found that the polar-bear-inspired hollow-tube design was lighter in weight and more resistant to heat flow. It was also hardly affected by water–a handy feature both for keeping polar bears warm while swimming and for maintaining insulation performance in humid conditions. As a bonus, the new material was extraordinarily stretchy, even more so than the hairs themselves, further boosting its engineering applicability.
Scaling up the manufacturing process to build insulators on the meter scale rather than the centimeter one will be the next challenge for the researchers as they aim for relevant industrial uses. “While our carbon-tube material cannot easily be mass produced at the moment, we expect to overcome these size limitations as we work toward extreme aerospace applications,” says Yu.
The Latest on: Synthetic heat insulator
via Google News
The Latest on: Synthetic heat insulator
- Best Thermal Underwear: Smart Base Layers for Cold Weatheron January 20, 2021 at 12:46 pm
Thermal underwear is the most important base layer for winter outings. Here’s what you need to consider before buying your next set.
- The 5 Best Eco-Friendly Puffer Jackets You Should Be Wearing This Winteron January 9, 2021 at 8:03 am
These are the best eco-friendly puffer jackets that will keep you cozy and warm all winter long and are made from recycled or alternative down.
- 15 Best Camping Blankets: Which is Right for You?on January 8, 2021 at 11:22 pm
This synthetic down ... ALPS has built the Wavelength with TechLoft Silver Insulation for effectively trapping your body heat, and a 20D 380T nylon shell for ensuring the blanket doesn’t ...
- 25 Best Snowboarding Gifts for Anyoneon January 8, 2021 at 11:17 am
Other features of the mittens include a removable four-way stretch DryRide liner, which dries quickly for added comfort; ThermaCore insulation for extra warmth; Screen Grab synthetic leather palm ...
- The best dog sweateron January 6, 2021 at 7:32 am
A dog sweater not only keeps your pal insulated but can also be a fashion ... Fleece is a superior option for warmth. This synthetic polyester material mimics the warmth of wool without the ...
- How to wash a sleeping bagon December 30, 2020 at 4:00 pm
Synthetic insulation is less delicate than down and doesn’t clump ... Use a second rinse cycle if possible, and at least one spin cycle. 4. Dry on lowest heat: Carefully move your sleeping bag into ...
- How to choose a sleeping bagon December 30, 2020 at 4:00 pm
Synthetic insulation uses polyester threads spun in continuous long ... Most 3-season and winter sleeping bags made for backcountry use have hoods that cinch tight to seal in heat. Draft collar: Also ...
- Phenolic Resins Market, Business Trends, Global Segments, Business Opportunities, Industry Profit Growth and Forecast to 2027on December 29, 2020 at 4:11 pm
Phenolic resins are synthetic polymers which are formed by step-growth polymerization. They are known for their outstanding heat resistance ... are used in molding, insulation, laminated veneer ...
- Best Outdoor Gear Deals of the Weekon December 22, 2020 at 4:00 pm
This 650-fill down parka is made with Heat Seal technology ... A waterproof membrane, synthetic insulation, and a microfiber lining provide the features you need in a winter boot.
- Best sleeping bag 2021: Stay cosy in any weather and all seasonson December 21, 2020 at 9:37 am
Heat retaining tricks include an aluminimised ... an excellent choice for potentially rain-lashed camping, as the synthetic insulation keeps you warm regardless of how wet it is.
via Bing News