Everything is NOT bigger in Texas

At least not at Alan G. MacDiarmid NanoTech Institute at the University of Texas at Dallas.
There, they're baking up carbon nanotubes--microscopic black tubes that are about 1/10,000th the diameter of a human hair! For those of you thinking, "carbon nano what?", here's a quick description: a carbon nanotube is an extremely thin cylinder of carbon whose structure gives it spectacular mechanical properties, including high strength and toughness. The development of this material could one day open the door to a whole new breed of strong materials, including stronger bridge suspension cables, battle jackets, concrete, fire protection and maybe even a space elevator. 
DavidandSci.jpgRecently our crew for the upcoming Materials Science mini series "Making Stuff" and host David Pogue paid NanoTech Institute a visit for a closer look at these tiny wonders. At the Institute, Dr. Ray Baughman and his colleagues are researching multiple projects in the field of nanotechnology including nanostructured hybrid composite membranes for fuel cells, carbon nanotube fiber supercapacitors, and highly energy efficient, low-voltage, organic light emitting devices. We focused on two of his incredible projects: the Spinning of Carbon Nanotube Composite Fibers and Carbon Nanotube Artificial Muscles.

To make carbon nanotube fibers, the scientists first create a Nanotube "forest." David Pogue described this process to me.

Creating a carbon nanotube "forest" goes like this:
1. Put a special metal coated sheet into a superhot lab oven.
2. Pump special gases into the chamber.
3. Extract the sheet, which now has what looks like jet-black velvet covering it.

But it's not velvet. If you touch it (after it cools), it's hard and crunchy-feeling. (Only after the camera stopped rolling did they tell me, "Oh, by the way, I wouldn't touch that stuff. Nobody knows if it's toxic or not." Great!) It's called a "forest" because even though it's only 1/8 inch tall, it's composed of billions of extremely tiny vertical carbon nanotube strands. The scientists can grab a clump of those tiny, tiny strands and pull them away from the forest--and as the nanotubes pull away from the forest, they stick to each other, eventually pulling away into the finest, gossamer, silky black ribbon. Its density is the same as air, so it basically just hangs there in space. You can keep pulling and pulling... A half-inch strip of "forest" on the slide can produce a ribbon 10 yards long when pulled this way!

nano ribbon.jpgThe result of this work is a yarn that pound-per-pound has the same stiffness and toughness of steel wire with twice the strength. ("Toughness," as you'll learn when our miniseries finally airs next fall, is only one of several scientific definitions of what the average person calls "strong.")

Next, we checked out Dr. Baughman's carbon-nanotube artificial muscle, which his team is designing at the request of the U.S. military. The hope is that one day, these muscles can drive advanced prosthetic limbs, power suits that will allow the average person to lift huge amounts of weight with ease (think "Iron Man"), or even robot soldiers who can refuel themselves. This particular muscle uses no electricity; instead, it responds to organic fuel, just as our own human muscles do.

The artificial muscle looks like a metal spring dangling from inside an upside down test tube, but when certain gases are sprayed onto this metal, it contracts, lifting a weight for demonstration purposes. The ability to use an organic fuel--methanol, for example--is hugely advantageous, allowing for 20 times more stored energy in a given space than the most advanced batteries.

Now, while this piece of technology is truly incredible, a spring, nailed to a plank, that lifts a weight just isn't much to look at. It was weeks ago while planning this shoot that our crew started wondering, "How can we make this more visually interesting?" Our solution: body builders!
Ray and BB.jpg
Left to Right: Chris Darby, Dr. Ray Baughman, Olivia Burgess

The idea here was to make the ability of the artificial muscles easily understandable to the viewers by giving them a clear visual. Our body builders, Olivia Burgess and Chris Darby, have highly developed muscles by most people's standards; they can each lift over 200 lbs. But with the strength of Dr. Baughman's artificial muscles, they would be able to lift about 50 tons! Now that's what you call a bench press!

Publicist's Note: MAKING STUFF: Stronger, Smaller, Cleaner, Smarter will premiere Wednesday, January 19, 2011 at 9pm ET/PT on PBS

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