A bit reminiscent of the Terminator T-1000, a new material created by Cornell researchers is so soft that it can flow like a liquid and then, strangely, return to its original shape.
Rather than liquid metal, it is a hydrogel, a mesh of organic molecules with many small empty spaces that can absorb water like a sponge. It qualifies as a "metamaterial" with properties not found in nature and may be the first organic metamaterial with mechanical meta-properties.
Hydrogels have already been considered for use in drug delivery -- the spaces can be filled with drugs that release slowly as the gel biodegrades -- and as frameworks for tissue rebuilding. The ability to form a gel into a desired shape further expands the possibilities. For example, a drug-infused gel could be formed to exactly fit the space inside a wound.
Dan Luo, professor of biological and environmental engineering, and colleagues describe their creation in the Dec. 2 issue of the journal Nature Nanotechnology.