Correct Answer: D
Explanation:
Phones with cracked screens is a common sight these days and scientists at University of California have come up with a method to solve this problem.
They have successfully created a self-healing material which when carved into two parts, can go back together like nothing has happened.
The material is a made up of stretchable polymer and an ionic salt.
It can stretch up to 50 times its original size also capable of conducting electricity.
All these features combined make it a viable material for producing smartphones screen.
The substance has potential applications in the field of soft robotics as well.
The polymer is based on the premise that materials consist of a mix of strong covalent bonds and weaker non-covalent bonds.
When a material gets damaged, non-covalent bonds protect covalent bonds by getting broken first.
As weak as these non-covalent bonds are, however, they’re also reversible, which means after they’re broken, they can also recover. And this cycle can be repeated over and over again.
The properties are attributed to a specific kind of bond called ion dipole interaction, basically force between ions and molecules.
What happens is that when the two ends of the broken material meet, this force causes the ions and molecules to get attracted to each other.
The ion-dipole interaction causes the broken non-covalent bonds to reunite and reform, resulting in the material healing its own damage.
The research team's inspiration for self-healing material was comes from Marvel superhero Wolverine!