Scientists have discovered a new material that dramatically expands or contracts when exposed to a weak electrical signal.
Many materials expand and contract in response to changes in temperature and pH levels. Materials in greenhouse windows, for example, automatically open and close to help regulate the temperature. Similar materials, both solids and gels, are used in robots and biomedicine applications.
Until now, however, scientists had failed to find a material that can dramatically alter its volume -- ideally, triggering a phase change -- in response to electricity.
While making and testing experimental materials in the lab, researchers in Sweden and Britain synthesized a polymer that can both expand and contract in response to a weak electrical signal.