There was a time when we all used the old Nokia 1100 phone. Those were some solid bricks, weren’t they? You could drown them, throw them at walls and do pretty much anything you wanted, and they’d still remain intact. But then, Steve Jobs and his iPhone came along and changed everything. Cell phones suddenly became extraordinarily delicate and difficult to handle.
But this wasn’t limited to just cell phones. Pretty much all of our electronics are incredibly delicate. Wouldn’t it be nice to have some electronics you can’t break? A team of Virginia Tech researchers asked the same question, and they might have created the answer.
Enter Soft Electronics
A research-based team from Virginia Tech Institute with backgrounds in mechanical engineering and macromolecules engineering has found a way to create a new type of electronics known as soft electronics. These devices are reconfigurable and recyclable, and, as if they weren’t already impressive-sounding, they’re capable of self-healing. The circuits used in them are relatively soft and stretchy, with a skin-like feel to them. They can sustain considerable damage even under load, and you can easily recycle them at the end of the product’s life.
The team, led by Assistant Professor Michael Bartlett, published their findings in the Communications Material Journal, an open-access journal by Nature Research.
Any electronic device today is made up of circuit boards that have wires soldered together, allowing electricity to pass through. However, these soft electronics replace those inflexible and irreparable wires with tiny, liquid metal droplets that conduct electricity.
An elastomer, a rubbery kind of polymer, is used to dispense the liquid metals as electrically insulated droplets. The droplets allow soft electronics to be more flexible in their functioning and sustain higher levels of damage that were not possible before.
Embossing To The Rescue
Postdoctoral researcher and first author of this research publication, Ravi Tutika, explains: “To make circuits, we introduced a scalable approach through embossing, which allows us to create tunable circuits by selectively connecting droplets rapidly. We can then locally break the droplets apart to remake circuits and can even completely dissolve the circuits to break all the connections to recycle the materials, and then start back at the beginning.”
Embossing is a technique that is generally used on paper-like material to raise 3-D like images on it. The liquid circuits use a similar approach to make and hold their circuits in place and run smoothly. This allows them to be solid and invulnerable to damage even when punctured.
Soft electronics are the best we have achieved in terms of creating sustainable electronics. Once the product’s lifespan ends, the metal droplets used in the circuitry, and the rubbery materials holding them together, can easily be reprocessed and reused by turning all of it into liquid material and making brand new circuitry out of them.
These circuits are (unfortunately) a long way from letting us make stretchy smartphones, but they’re the closest we have ever been to making sustainable and damage-proof devices in recent history.