Self-healing smartphones inspired by WOLVERINE could be made using a new material that stretches to 50 times its normal length

A stretchy, self-healing material could help make the next generation of durable electronics and robots.
 
The material is stretchable and transparent, conducts ions to generate current and could one day help your broken smartphone to repair itself.
 
And the researchers' inspiration for the futuristic technology comes from an unlikely source - X-Men's invincible superhero Wolverine.
 
'When I was young, my idol was Wolverine from the X-Men,' study lead author Professor Chao Wang said.
 
'He could save the world, but only because he could heal himself.
 
'A self-healing material, when carved into two parts, can go back together like nothing has happened, just like our human skin.
 
'I've been researching making a self-healing lithium ion battery, so when you drop your cell phone, it could fix itself and last much longer.'
 
Professor Wang and his team, based at John Hopkins University in Baltimore, Maryland, created a material based on a mixture of chemical bonds that gives it strange abilities.
 
It could stretch up to 50 times its usual size, and after being torn in two the material automatically stitched itself back together within a day.
 
As a test, the researchers generated an 'artificial muscle' by placing a non-conductive membrane between two layers of the conductor.
 
The new material responded to electrical signals, bringing motion to these artificial muscles, so-named because biological muscles similarly move in response to electrical signals.
 
Professor Wang says that the key to self-repair is in the chemical bonding. Two types of bonds exist in materials, he explains.
 
Covalent bonds are strong and don't readily repair once broken, while non-covalent bonds, which are weaker and more dynamic.
 
'The mechanism of the self-healing polymer is that the strong covalent bonds and weaker non-covalent bonds exist in the materials at the same time,' Professor Wang told MailOnline.
 
'When there is a mechanical damage, the weaker non-covalent bonds will break first to protect the strong covalent bonds.
 
'However, these non-covalent bonds are reversible, which means that they can be broken and recovered many times.'
 
When the two ends of the split material touch, the broken bonds re-form, Professor Wang said.
 
'This drives the polymer chains to diffuse through the interfaces. Therefore, the polymers can recover and the mechanical properties can be healed,' he said.
 
For their next step, the researchers are working on altering the polymer to improve the material's properties.
 
For example, they are testing the material in harsh conditions, such as high humidity.
'Previous self-healing polymers haven't worked well in high humidity, Professor Wang said.
'Water gets in there and messes things up. It can change the mechanical properties.
 
'We are currently tweaking the covalent bonds within the polymer itself to get these materials ready for real-world applications.

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