Researchers develop 3D-printable biosignal hydrogel and recyclable plastic

Researchers at Pennsylvania State University have developed a 3D-printable conductive hydrogel, known as RTLR gel, designed to monitor physiological signals through skin, hair, and sweat. Led by Professor Huanyu Cheng, the team created an extremely soft and adhesive material that adapts to the physical contours of the skin. This flexibility helps maintain stable electrical contact and reduces signal noise caused by body movement, which typically causes traditional, more rigid sensors to detach or lose accuracy.

In a separate development, engineers at the University of Surrey have introduced a new type of plastic with unique thermal properties. Published in the journal Macromolecules, the study describes a polymer that decomposes into a gas-like state when heated and reforms into solid flakes upon cooling. Lead author Peter Roth noted that while most plastics are designed for stability—making them difficult to recycle—this material can be easily transformed and recovered, potentially offering a new solution to combat plastic pollution and microplastics.