Just imagine how great it would be if you could drop your cellphone and it would bounce rather than break. Or if you could run over your laptop with a tank and it would just blob out and reform itself. This is the sort of thing that's possible with stretchable and flexible electronics, and it's being worked on right now.
At Northwestern University, researchers there have come up with electronics that can be stretched 200% and still work.
The hardest part about making electronics that flex and stretch is keeping all the conductive pathways linked up. We've seen lots of things that can bend and twist, but that's all stuff that you can do with wires while maintaining their dimensions. What you can't do with wires is stretch them out and the shrink them back again while maintaining efficient conductivity, but researchers at Northwestern's McCormick School of Engineering have solved this wiring problem by using liquid metal instead.
The researchers first created a highly porous three dimensional structure out of a rubbery substance that can be stretched to 300% of its original size and then spring back. Then, they filled the inside of the rubbery thing with a conductive liquid metal, resulting in a structure that can be stretched to make it 200% longer while still being entirely conductive. Plus, it can be stretched and released over 10,000 times without losing any conductivity at all.
As much as we all want Stretch Armstrong cellphones (I know I do!), the first place we might see this kind of tech is in implantable electronics that need to stretch and flex with whatever body parts they're attached to.