A material that thickens when you pull on it seems to contradict the laws of physics. However, the so-called auxetic effect, which also occurs in nature, is interesting for a number of applications. A new Empa study recently published in Nature Communications (“Random auxetics from buckling fibre networks”) shows how this amazing behavior can be improved – and even used to treat injuries and tissue damage.
Nature shows us how to do it: A calf sucking milk from the udder of a mother cow uses a fascinating physical property of the teat, which consists of an auxetic tissue. Paradoxically, such tissues do not become narrower under tension, such as a rubber band, but wider, transverse to the direction of pull. Therefore, the cow’s milk can flow unhindered through the teat.
Empa scientists have now demonstrated the astonishing auxetic properties of nanofiber membranes developed specifically for this purpose. The study published in Nature Communications points to a wide range of applications for auxetic materials, including the use of auxetic membranes to regenerate human tissue after injuries.

Image Credit:  EMPA/Youtube

Read more at nanowerk.com

News This Week

Walking with atoms

Ever since it was proposed that atoms are building blocks of the world, scientists have been trying to understand how and why they bond to each other. Be it a molecule (which is a [...]

Illuminating the world of nanoparticles

Scientists at the Okinawa Institute of Science and Technology Graduate University (OIST) have developed a light-based device that can act as a biosensor, detecting biological substances in materials; for example, harmful pathogens in food [...]

Self-driving microrobots

Most synthetic materials, including those in battery electrodes, polymer membranes, and catalysts, degrade over time because they don't have internal repair mechanisms. If you could distribute autonomous microrobots within these materials, then you could [...]