Pulling too hard on a synthetic soft material like a rubber band usually leads to its failure. However, some biological soft materials, like our muscles, experience the opposite behavior. Our muscles, for instance, grow by repairing damage caused by a mechanical effort, such as lifting weigths. A team of researchers from Hokkaido University successfully mimicked this biological process and applied it to develop hydrogels that get stronger under tensile stress.
Soft engines: Leidenfrost effect in elastic solids
Have you ever wondered why a water droplet rolls around on a hot pan instead of evaporating instantly? The part of the droplet touching the pan does indeed evaporate. The resulting vapor forms a thin insulating layer that enables the drop to hover over the pan for seconds, even minutes. This is known as the Leidenfrost effect. Because they also produce vapor when heated, sublimable solids (solids that skip over the liquid phase and directly produce vapor) also exhibit the Leidenfrost effect. This effect has been studied extensively for both liquids and sublimable solids.