WASHINGTON, Feb. 9 (Xinhua) -- Scientists from University of Colorado Boulder have developed a new type of malleable, self-healing and fully recyclable "electronic skin" that can be used in biomedical devices like artificial limbs.
In a paper published Friday in the journal Science Advances, researchers made an electronic skin with sensors to measure to pressure, temperature, humidity and air flow. The electronic skin is a thin, translucent material that can mimic the function and mechanical properties of human skin.
It used a novel type of covalently bonded dynamic network polymer, known as polyimine, that has been laced with silver nanoparticles to provide better mechanical strength, chemical stability and electrical conductivity.
"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 Jianliang, assistant professor from University of Colorado Boulder who led the study.
"Given the millions of tons of electronic waste generated worldwide every year, the recyclability of our e-skin makes good economic and environmental sense," Xiao said.
The skin can be easily conformed to curved surfaces like human arms and robotic hands by applying moderate heat and pressure to it without introducing excessive stresses.
To recycle the skin, the device is soaked into recycling solution, making the polymers degrade into oligomers, polymers with polymerization degree usually below 10, and monomers, small molecules that can be joined together into polymers, both of which are soluble in ethanol. The silver nanoparticles sink to the bottom of the solution.
"The recycled solution and nanoparticles can then be used to make new, functional e-skin," said Xiao.