Photograph of the e-skin courtesy of CU Boulder.
Researchers at the University of Colorado (CU) Boulder have developed a new type of malleable, self-healing, and fully recyclable electronic skin that has applications in prosthetic development, robotics, and biomedical devices. Electronic skin, or e-skin, is a thin, translucent material that can mimic the function and mechanical properties of human skin. The latest e-skin has embedded sensors that measure pressure, temperature, humidity, and air flow.
The technology has several distinctive properties, including a novel type of polymer, known as polyimine, that has been laced with silver nanoparticles to provide better mechanical strength, chemical stability, and electrical conductivity, said Jianliang Xiao, PhD, an assistant professor in the Department of Mechanical Engineering, who is leading the research effort with Wei Zhang, PhD, an associate professor in the Department of Chemistry and Biochemistry as well as a faculty member in the Materials Science and Engineering Program.
“What is unique here is that the chemical bonding of polyimine we use allows the e-skin to be both self-healing and fully recyclable at room temperature,” said Xiao. “Given the millions of tons of electronic waste generated worldwide every year, the recyclability of our e-skin makes good economic and environmental sense.”
Another benefit of the CU Boulder e-skin is that it can be easily conformed to curved surfaces like human or prosthetic arms and hands by applying moderate heat and pressure to it without introducing excessive stresses. Healing of cut or broken e-skin, including the sensors, is done by using a mix of three commercially available compounds in ethanol, said Zhang, and a recycling solution degrades the polymers and separates the silver nanoparticles for reuse.
The research was published February 9 in Science Advances.
Editor’s note: This story was adapted from materials provided by CU Boulder.