Programmable Hydrogel Not Such a Stretch
Jelly-like polymer can be designed to shrink and grow

Researchers at the University of North Carolina at Chapel Hill have developed a hydrogel material that can change shape at predetermined rates, without external triggers like light, heat, or water. As their proof of concept, the team created a hydrogel flower that bloomed over a two-hour span. Within the closed system of the human body, the ability of this hydrogel to autonomously shapeshift over a predetermined time range is a big advantage. Leveraged in conjunction with 3D printing, biomedical implants could be designed to change size and shape as needed.

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