Here is an electrically insulating composite with metal-like thermal conductivity and elasticity similar to biological tissue that can prove useful for developing robotic muscles. Thubber can stretch over 6 times its initial length.
Our combination of high thermal conductivity and elasticity is especially critical for rapid heat dissipation in applications such as wearable computing and soft robotics, which require mechanical compliance and stretchable functionality
explains Majidi, an associate professor of mechanical engineering at Carnegie Mellon University. While this technology can be used to develop soft robots, it also has wearable applications. The above video shows a soft robotic fish that swims with a thubber tail without conventional motors.