A team of experts in mechanics, materials science, and tissue engineering at Harvard have created an extremely stretchy and tough gel that may pave the way to replacing damaged cartilage in human joints or spinal disks. Called a hydrogel, because its main ingredient is water, the new material is a hybrid of two weak gels that combine to create something much stronger. This new gel can stretch to 21 times its original length, but it is also exceptionally tough, self-healing, and biocompatible — a valuable collection of attributes that opens up new opportunities in medicine and tissue engineering. It could also be used in soft robotics, optics, artificial muscle, as a tough protective covering for wounds, or “any other place where we need hydrogels of high stretchability and high toughness,” the researchers suggest. “Conventional hydrogels are very weak and brittle — imagine a spoon breaking through jelly,” explains lead author Jeong-Yun Sun, a postdoctoral fellow at the Harvard School of Engineering and Applied Sciences (SEAS). “But because they are water-based and biocompatible, people would like to use them for some very challenging applications like artificial cartilage or spinal disks. For a gel to work in those settings, it has to be able to stretch and expand under compression and tension without breaking.” (via Tough super-stretchable gel is tougher than cartilage and heals itself | KurzweilAI)
