By Candace Stuart
Small Times Senior Writer
Dec. 14, 2001 — Business is sometimes likened to a Darwinian world where companies compete for dominance, in the process winnowing out the weak to leave a few strong commercial enterprises. That scenario seems to be playing out in what is perhaps the hottest and most hyped branch of nanotechnology, carbon nanotubes.
Companies from around the world, from the tiny island nation of Cyprus to the giant republic of China, are claiming
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| These are fibrils, magnified 200,000 times. Fibrils are a form of carbon nanotube made by Hyperion Catalysis International Inc. of Cambridge, Mass. They can be mixed into resins that form plastic car parts, making the material electrically conductive. The plastics then can be painted using an electrostatic process that reduces waste. COMING MONDAY: China intensifies its own nanotube research |
“Carbon nanotubes have so many unique physics about them that you have to believe something will happen, that they will do something useful,” said Mildred Dresselhaus, a professor of electrical engineering and physics at the Massachusetts Institute of Technology who has authored several texts and research papers on nanotubes.
Sumio Iijima of NEC Corp. discovered carbon nanotubes in 1991 in Tsukuba, Japan, while working on buckminsterfullerenes, all-carbon molecules shaped like soccer and rugby balls. The hollow nanotubes extend like straws with the same tendency to bend and spring back. Later research showed they formed in bundles of tubes within tubes (multi-walled) and a nanometer-wide tube (single-walled). Individual tubes are either metallic or semiconductors, depending on how their carbon atoms stack up.
Recently, several corporations have demonstrated uses for carbon nanotubes. The Korean manufacturing giant Samsung unveiled a prototype field emissions display using multi-walled nanotubes. Samsung claims nanotube-based flat panel displays need less voltage than traditional cathode ray tubes to produce the same mount of light.
In the United States, IBM made a transistor using single-walled carbon nanotubes that could be used in molecular-size electronic devices. The devices are expected to perform faster and better than existing technologies.
NEC sees a niche for yet another carbon nanotube variant called the nanohorn. NEC is working on making a carbon nanohorn electrode that it claims can create 20 percent more power in fuel cells used in laptop computers and mobile phones.
Researchers have been making nanotubes in small quantities for years using arc discharge and laser ablation techniques, methods that don’t readily lend themselves to larger scale production. That has prompted companies to invent and patent more cost-effective and efficient means to commercialize tubes.
“Anybody can go in the lab and make carbon nanotubes,” said Patrick Collins, marketing director of nanotube supplier Hyperion Catalysis International Inc. of Cambridge, Mass. “But making a gram is not the same as making a kilogram or a ton.”
Hyperion patented a technique using ethylene and other materials to make a form of carbon nanotube four years before Iijima’s breakthrough. The company produces tubes called fibrils that resemble tightly rolled sheets of carbon. Fibrils can be mixed into resins that form plastic car parts, making the material electrically conductive. The plastics then can be painted using an electrostatic process that reduces waste and pollution.
GE Plastics of Pittsfield, Mass., incorporated fibril additives into plastic casings for exterior car mirrors, starting with the 1997 Ford Taurus and Mercury Sable models. Auto suppliers also are considering fibrils for bumpers and fuel lines. The electronics industry, which already uses the material for disk drive manufacturing, offers another potential market.
Founded in 1982, Hyperion has matured to the pilot plant stage and is capable of supplying large quantities of fibrils if demand grows, Collins said. “We could make millions of tons,” he said. “We see applications that could be that large in plastic auto parts.”
Hyperion faces competitors at home and abroad as more and more manufacturers find ways to not only produce nanotubes but also make specific types. Not all types are suitable for all applications. Hyperion’s fibrils and other multi-walled tubes have wider diameters and consequently less predictable characteristics than single-walled carbon nanotubes, for instance.
Hyperion also is looking at ways to produce single-walled tubes. But those, too, have their own limitations, Dresselhaus said, because their atom-thick wall makes them extremely delicate.
Carbon Nanotechnologies Inc. (CNI) in Houston is positioning itself to be a leading supplier of the single-walled variety using its patented High Pressure Carbon Monoxide (HiPco) process. Designed by fullerene pioneer Richard Smalley’s research group, the process allows continuous production of single-walled carbon nanotubes with a consistently small diameter. Smalley is a co-founder of CNI and co-discoverer of buckminsterfullerenes, for which he and two other chemists share a Nobel Prize.
Although less than two years old, the company expects to have a pilot plant working by February in a 6,000-square-foot facility. CNI will use its three reactors to test a wide range of production processes in efforts to increase yield and lower cost, said CNI chief executive Bob Gower. His goal is to have a commercial plant running by 2005.
“Even if we could not make any bit of improvement, we could sell (tubes) at $2,000 a pound,” Gower said. “That would be the worst case. With modest improvements, we could get that to $200 a pound. I believe we’ll get it below $100 a pound.”
Other prominent producers scattered across the globe include NanoLab and Materials and Electrochemical Research Corp. in the United States; Mitsubishi and Showa Denko in Japan, and Sun Nanotech Co. Ltd. and Shaanxi Nanfeng Chemical Industry Group Shareholdings Co. Ltd. in China. In November, the chemical industry group announced that it and researchers at Tsinghua University developed a catalytic chemical vapor deposition method to batch produce nanotubes. The company says it can make 15 kilograms, or 33 pounds, of nanotubes an hour.
Rosseter Holdings Ltd. of Limassol, Cyprus, claims that it, too, can produce large quantities of single-walled and multi-walled tubes as well as nanohorns with arc discharge method that uses hydrocarbon liquids. The liquid method requires less energy, according to Rosseter, which lowers the cost of production. Rosseter says one generator can produce 3 kilograms, or 6.6 pounds a week. But to increase yield, the company must build more generators.
“We have the flexibility to expand with generators,” said Christina Chaillou, Rosseter’s marketing manager. Building generators is “reasonably inexpensive,” she added. The company, which was formed in 1998, is now providing samples to clients, mostly in Asia.
All production methods create impurities as well as tubes. The application will determine not only what type of tube is needed — single- or multi-walled or nanohorn — but the relative purity as well. Quality will become an increasingly important factor as applications take hold, Gower said.
CNI plans to offer consistently top-end single-walled nanotubes because they provide the most enhanced properties, he said. “Our belief is you have to unite a product of high quality that is highly reproducible. We feel most of these people (competitors) will fall by the wayside.”
Hyperion expects to make strides as an established supplier of multi-walled tubes, Collins said, by continuing to build its client base and reputation. The privately held company already employs a staff of 70. “We’re making real money with commercial sales.”
Both Hyperion and CNI are strengthening their intellectual property positions for what they see as a burgeoning market. In two months, CNI expects to have 50 patents issued or applied for that cover compositional matter and related applications, such as ways to align or disperse tubes.
Rosseter, too, is pinning some of its hopes on its patents, Chaillou emphasized. “The company would not rule out licensing our technology,” she said.
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