Graphene and Silly Putty mix to create powerful sensors

silly putty graphene
Trinity College Dublin

We all knew Silly Putty was special -- the elastic-y, liquid-y toy is tons of fun to use.

Well, now it has scientific applications, also. Researchers have discover that Silly Putty, when mixed with graphene, has some unusual properties. I wonder what other kids' toys are secret scientific materials?

In IT Blogwatch, it's time to learn something new.

What exactly is going on? Sophie Bushwick has the background:

It’s easy to dismiss Silly Putty as a kid’s toy. But...when you mix Silly Putty with graphene -- strong, conductive carbon sheets with unusual physical properties -- it becomes an incredibly sensitive strain detector that can track blood pressure, heart rate, and even a spider’s footsteps.

Graphene. Isn't that the super strong wonder material? Daniela Hernandez fills us in:

Graphene is an...appealing substance for building electronics because it is lightweight and flexible; it is hundreds of times as strong as steel; and it conducts electricity extremely well. In recent years, scientists...have shown interest in using it for commercial applications, like gas sensors, tennis rackets and microprocessors.

And Silly Putty? Isn't what we used as kids to pick up the ink of newspapers (something people read the news on back in the day, before smartphones and tablets)? Well, now it has scientific applications, as well. Amy Middleton has the details:

The putty is a lightly cross-linked silicone polymer that bounces, breaks and flows...In technical terms, it is “highly viscoelastic”...Putting graphene into the mix...dampened its performance -- but it nevertheless remained defiantly silly.
...
Once combined, the...nanocomposite displayed unusual behavior in response to impact and strain. The result was a highly sensitive material that could be developed into an ultra-precise motion and pressure sensor.

So what exactly did scientists do? Mark Peplow is in the know:

The researchers mixed graphene flakes, roughly 20 atomic layers thick and up to 800 nanometers long, with homemade Silly Putty...to produce dark grey G-putty that conducted electricity...its electrical resistance changed dramatically when the researchers applied even tiny amounts of pressure. The putty was at least ten times more sensitive than other nanocomposite sensors.
...
When they wired up a lump of G-putty and held it to a student’s neck, the pulse from his carotid artery was...visible in those resistance changes...the pulse profile was so detailed that they could convert it into an accurate blood-pressure reading. The sensor could...monitor respiration when placed on the student’s chest. And...it recorded the individual steps of a spider weighing just 20 milligrams.

So what are the practical applications? We let Trinity College Dublin give us its official line:

This...research, led by School of Physics Professor Jonathan Coleman from TCD and in collaboration with Prof. Robert Young of the University of Manchester...offers exciting possibilities for applications in new, inexpensive devices and diagnostics in medicine and other sectors...The G-putty...works as a very sensitive impact sensor...It is believed that this material will find applications in a range of medical devices.

Surely this discovery was based on years of planning, right? Not quite. Glen McDonald explains:

The discovery of G-putty ... came after a postdoctoral researcher suggested mixing graphene and Silly Putty. It was essentially an accident...albeit the kinda-sorta deliberate accident that scientists like to encourage when mucking about in the lab.

Copyright © 2016 IDG Communications, Inc.

  
Shop Tech Products at Amazon