Wolverine from X-Men has an incredible ability to regenerate damaged tissues and heal wounds almost instantly. Now Wolverine has inspired scientists at the University of California-Riverside to develop a self-healing material that could help robots self-heal after a mechanical failure. Findings of the study were published in the journal Advanced Materials.
The material heals fully in 24 hours
The soft, rubber-like transparent material is highly stretchable, and starts healing immediately after being cut. It could be electrically activated to power artificial muscles. Scientists said it could also help improve electronic devices, batteries, and robots. Upon being cut, the material heals completely within 24 hours. In fact, it can be stretched two times of its original length only after five minutes of healing.
The material can stretch up to 50 times its original length. Self-healing is achieved through a mechanism called “ion-dipole interactions.” It was the first time researchers have been able to create ionic conductors, materials that can conduct electricity through the flow of ions, with self-healing properties, said Chao Wang, the co-author of the study.
The biggest challenge before scientists
Scientists have been able to develop transparent and stretchable ionic conductors in the past. But adding self-healing properties was difficult because it required formation of non-covalent bonds between molecules that do not share electrons. Also, non-covalent bonds degrade when electricity is passed through them.
Chao Wang and his colleagues were able to overcome this problem by using ion-dipole interactions to hold the molecules together. It combines charged ions with polar molecules that are highly stable under electrochemical conditions. A tiny electrical imbalance in molecules triggers an electrostatic attraction between them, giving the material self-healing properties.
The Wolverine-inspired material has several applications
The artificial muscles react upon receiving a signal, just like human muscles move when they get signals from the brain. The scientists were able to demonstrate the new material’s ability to self-heal on a dielectric elastomer actuator or artificial muscle. Researchers cut parts of the artificial muscle into two separate pieces. The Wolverine-inspired material healed without support from any external stimuli.
Chao Wang said in a statement that creating a self-healing material has been a “puzzle for many years.” Now that they have developed the material, researchers are exploring its applications. Besides giving robots the ability to self-heal after a mechanical failure, the material can be used to extend the life of lithium-ion batteries in electronic devices and electric cars. It can also help improve biosensors used in the environmental monitoring and medical science.