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No shadows and mirrors -- a Nanocomp employee poses next to a 3x6 ft sample mesh composed of randomly overlapping millimeter long carbon nanotubes.  (Source: Nanocomp Technologies)

The birthplace of the nanotube sheets is Nanocomp's high-tech tube-processing "Big Box", which can churn out a full-sized sheet per day.  (Source: Nanocomp Technologies)
Company makes 3x6 ft carbon nanotube sheets, 100 sq. ft. sheets by the end of the summer; possible uses include consumer electronics, aircraft, and spacecraft

Carbon nanotubes are like a materials scientists' dream come true -- superior heat and electrical conduction, high strength to weight ratio, and flame resistance orders of magnitude higher than many commonly used materials. 

However, in the past, while these tiny tube-molecules composed carbon atoms were raved about by researchers, plans for practical applications remained largely in the realm of fantasy.  The chief problem was the "nano" part of the nanotubes -- these tiny tubes would need to be scaled to visible-sized pieces of material in order to be utilized in many practical devices.  Such scaling  had enjoyed little previous success, and was seen as a major roadblock to putting the ubiquitous nanotubes to work.

Now a breakthrough from Nanocomp Technologies, a New Hampshire startup, promises to provide sheets composed of carbon nanotubes on an unprecedented scale.  Using nanotubes measuring in the tens of nanometers, Nanocomp produces sheets of carbon nanotubes measuring 3 by 6 feet.  Better yet, by the end of the summer the company is promising slabs of 100 square feet or more.

Nanocomp says that the days of waiting for nanotubes materials to be manufactured on a usable scale are over.  The company is taking production seriously, and is not looking to remain in the realm of pure research.  Says CEO and co-founder of Nanocomp, Peter Antoinette, "From the get-go, we wanted to build something that would be manufacturable.  We’re out to make value-added components out of that material."

The hardest part about making nanotube materials is growing long enough tubes.  Nanocomp makes a powder of tubes that are approximately 1 mm, a relatively long length.  In a highly secretive process Nanocomp takes a carbon source such as ethanol or methanol, heats it and flows it past a nanoparticle catalyst, which experts speculate to possibly be an oxide of nickel, cobalt or iron.  The carbon molecules react with the catalyst, powered by the heat, forming a nanotube.  The size of the catalyst correlates to the size of the nanotube formed.

The big hurdle was maintaining a large enough catalyst, keeping it stable enough for millimeter long tubes to grow.  Antoinette says that in order to achieve this, Nanocomp uses an advanced computer controlling 30 different parameters in the process, including temperature, temperature gradient, gas flow rates, and the chemical composition of the mix.  Using this precision control, researchers can both control the desired tube length and select from single-walled or multi-walled tubes.  Mr. Antoinette states, "We can dial it in."

The resulting nanotubes are arranged randomly overlapping into the large final sheets.  To give an idea of the sheet's strength, it has a tensile strength of 200 to 500 megapascals -- aluminum has a strength of approximately 500 megapascals.  Better yet, if Nanocomp moves from a random alignment to an organized alignment, the nanotube material could have a tensile strength as high as 1,200 megapascals. 

Antoinette comments that Nanocomp is heavily marketing the material to consumer electronics manufacturers and is receiving substantial interest.   In cell phone handsets, the material could help to provide protection against stray signals, thanks to its superior shielding against electromagnetic interference (EMI).  This could yield clearer sound and reception.  Also under consideration is the the use of the material in PDAs and laptops.  The material would provide such portable electronics with both heat dissipation from their chipsets and processors and EMI shielding from unwanted signals, via its randomly aligned nanotubes.  Better yet, smaller strips of aligned nanotubes could act as powerful antennas, grabbing wireless signals for superior network reception and transmission.

Nanocomp wants to eventually use the material in composites similar to the carbon-composite used to build the new Boeing 787 jets.  Current composites can't conduct electricity making them vulnerable to lightning strikes.  Nanotube composites could safely channel strikes to harmless locations, protecting the aircraft's electronics.  As an added benefit, current could be run through the nanotubes to heat up the aircraft body, and provide additional de-icing capabilities.

Antoinette points out that most of aerospace industry still uses pure copper wire for its conductors -- virtually the same copper wire used since the 1850s.  His company's nanotubes could replace this material with better conducting nanotubes, which weigh a mere 20 percent as a much as the copper wiring per volume.  Antoinette adds, "Copper wire is still the conductor of all our satellites, all our aircraft."

He points out that a current 747 jet has two tons of copper wire aboard -- a weight cost that could be cut in half by the use of nanotubes.  He says, "you’re talking literally millions of dollars of savings in fuel costs over the life of an airplane."

Boeing, Lockheed Martin, and Northrop Grumman are, needless to say, very excited about the potential for the new large scale material.  They have already qualified Nanocomp as a vendor and are currently receiving and testing samples of the material from Nanocomp.  In hopes of meeting these and other industry leaders demands, after the 100 sq. ft. samples are complete, Nanocomp plans on focusing its efforts on having a pilot-plant running by 2010, with full scale production by 2012.

David Lashmore, Nanocomp co-founder and Chief Technology Officer, pioneered the material assembly process.  The other co-founder was Robert Dean, a former engineering professor at Dartmouth who started Synergy Innovations, a high-tech incubator in Lebanon, NH.  The pair joined with Antoinette to start up the exciting new firm.  They've received  a $2.5M USD contract from the U.S. Army and a Small Business Innovation Research grant from the Air Force.  They are currently raising additional private financing.  To protect itself legally, Nanocomp has signed a non-exclusive license with IBM for IBM's single-wall nanotube process.  With 16 of its own patents, Nanocomp looks to safeguard its own prospects as well.


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RE: ?
By kkwst2 on 3/3/2008 1:58:10 PM , Rating: 2
I'm not sure this is really the major consideration. I think the main problem is where the electricity goes instead. Possibilities include electronics, fuel tanks, etc. You would like it to conduct through the body of the plane away from vulnerable equipment, etc. Also a discharge through a non-conductive material will potentially create a lot of heat and potentially warping/damage to the non-conductive material.

Do you have a link to the concept of an electrostatic charge attracting lightning?


RE: ?
By PlasmaBomb on 3/3/2008 4:40:30 PM , Rating: 2
Negative charges can act as a streamer and attract positive lightning.

http://en.wikipedia.org/wiki/Lightning
http://www.aerospaceweb.org/question/design/q0234....

Perhaps not the best links but it should get you started :)


RE: ?
By MrDiSante on 3/3/2008 8:46:41 PM , Rating: 2
Thank you sir, I will now worry myself silly over a form of lightning that is less than 5% of lightning strikes.


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