This Shape-Shifting Gel Can Move Itself Over Time

A Clockwork Hydrogel

In the wild world of smart materials there are some that can assemble themselves, but they usually need a nudge from an outside source, like adding light, heat or water in order to start the shape-shifting process.

In a paper published today in Nature Communications, researchers announced that they have created a material that can change shape over time, without an external cue.

Inspired by the mechanical properties of a watch, researchers at the University of North Carolina at Chapel Hill created a hydrogel (a jelly-like polymer) that can be programmed to move into different positions over time.

To demonstrate the concept, the team built a blooming flower that could unfurl gradually, with each layer of petals opening at an appointed time. The hydrogel can be programmed by adjusting a molecular ‘spring’ inside the material, which can be set to change shape over a matter of seconds or hours.

The researchers hope a material that can unfold at a pre-determined pace may lead to devices that could work in healthcare settings, with the potential to expand or grow in the human body as needed.