Your world in the future is going to be made of buckypaper.Buckypaper is 10 times lighter but potentially 500 times stronger than steel when sheets of it are stacked and pressed together to form a composite. Unlike conventional composite materials, though, it conducts electricity like copper or silicon and disperses heat like steel or brass. It is made from tube-shaped carbon molecules 50,000 times thinner than a human hair. Due to those unique properties, it is envisioned as a wondrous new material for light, energy-efficient aircraft and automobiles, more powerful computers, improved TV screens and many other products. So far, buckypaper can be made at only a fraction of its potential strength, in small quantities and at a high price, but researchers are developing manufacturing techniques that soon may make it competitive with the best composite materials now available.
First, understanding the buckypaper. In 1985, researchers experimented to create the same conditions that exist in a star. They wanted to find out how stars, the source of all carbon in the universe, make the element that is a main building block of life, and verything went as planned - with one exception: a molecule with 60 carbon atoms shaped like a soccer ball. It also looked like the geodesic domes promoted by Buckminster Fuller, an architect, inventor and futurist, which inspired the new molecule name buckminsterfullerene, or "buckyballs" for short.
For the discovery of the buckyball — the third form of pure carbon to be discovered after graphite and diamonds — the three scientists were awarded the Nobel Prize for chemistry in 1996. Separately, a Japanese physicist developed a tube-shaped variation. Researchers then inadvertently found that the tubes would stick together when disbursed in a liquid suspension and filtered through a fine mesh, producing a thin film — buckypaper. If you were to take a gram of nanotubes and if you unfold every tube into a graphite sheet, you could cover about two-thirds of a football field.
Currently, carbon nanotubes are already beginning to be used to strengthen tennis rackets and bicycles, but in small amounts. The epoxy resins used in those applications are 1 to 5% carbon nanotubes, which are added in the form of a fine powder. Buckypaper, which is a thin film rather than a powder, has a much higher nanotube content — about 50%. One challenge was that the tubes clump together at odd angles, limiting their strength in buckypaper. Exposing the tubes to high magnetism causes most of them to line up in the same direction, increasing their collective strength. Another problem is the tubes are so perfectly smooth it's hard to hold them together with epoxy. Researchers are looking for ways to create some surface defects (but not too many)to improve bonding.
So far, an institute in Florida has been able to produce buckypaper with half the strength of the best existing composite material, known as IM7, and by the end of next year we should have a buckypaper composite just as strong as IM7, but 35% lighter.
First, understanding the buckypaper. In 1985, researchers experimented to create the same conditions that exist in a star. They wanted to find out how stars, the source of all carbon in the universe, make the element that is a main building block of life, and verything went as planned - with one exception: a molecule with 60 carbon atoms shaped like a soccer ball. It also looked like the geodesic domes promoted by Buckminster Fuller, an architect, inventor and futurist, which inspired the new molecule name buckminsterfullerene, or "buckyballs" for short.
For the discovery of the buckyball — the third form of pure carbon to be discovered after graphite and diamonds — the three scientists were awarded the Nobel Prize for chemistry in 1996. Separately, a Japanese physicist developed a tube-shaped variation. Researchers then inadvertently found that the tubes would stick together when disbursed in a liquid suspension and filtered through a fine mesh, producing a thin film — buckypaper. If you were to take a gram of nanotubes and if you unfold every tube into a graphite sheet, you could cover about two-thirds of a football field.
Currently, carbon nanotubes are already beginning to be used to strengthen tennis rackets and bicycles, but in small amounts. The epoxy resins used in those applications are 1 to 5% carbon nanotubes, which are added in the form of a fine powder. Buckypaper, which is a thin film rather than a powder, has a much higher nanotube content — about 50%. One challenge was that the tubes clump together at odd angles, limiting their strength in buckypaper. Exposing the tubes to high magnetism causes most of them to line up in the same direction, increasing their collective strength. Another problem is the tubes are so perfectly smooth it's hard to hold them together with epoxy. Researchers are looking for ways to create some surface defects (but not too many)to improve bonding.
So far, an institute in Florida has been able to produce buckypaper with half the strength of the best existing composite material, known as IM7, and by the end of next year we should have a buckypaper composite just as strong as IM7, but 35% lighter.
They expect buckypaper's first uses will be for electromagnetic interference shielding and lightning-strike protection on aircraft. Electrical circuits and even natural causes such as the sun or Northern Lights can interfere with radios and other electronic gear - buckypaper provides up to four times the shielding, as specified in a recent Air Force contract proposal. Typically, conventional composite materials have a copper mesh added for lightning protection. Replacing copper with buckypaper would save weight and fuel. To demonstrate this, a composite model plane and a stun gun were used. Zapping an unprotected part of the model caused sparks to fly. The electric jolt, though, passed harmlessly across another section shielded by a strip of buckypaper.
Other near-term uses would be as electrodes for fuel cells, super capacitors and batteries, an could be a more efficient and lighter replacement for graphite sheets used in laptop computers to dissipate heat. The long-range goal is to build planes, automobiles and other things with buckypaper composites. The military also is looking at it for use in armor plating and stealth technology.
Other near-term uses would be as electrodes for fuel cells, super capacitors and batteries, an could be a more efficient and lighter replacement for graphite sheets used in laptop computers to dissipate heat. The long-range goal is to build planes, automobiles and other things with buckypaper composites. The military also is looking at it for use in armor plating and stealth technology.
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