IT'S ELEMENTAL!
factants to stabilize aqueous fire-fighting foams. Fluorocarbons are also used asfireextinguishants in aerospace and other critical areas. Modern high-energy-density lithiumion batteries used in handheld electronic NANCE K. DICCIANI, SPECIALTY MATERIALS, HONEYWELL devices rely on LiPF 6 . And there's even more. Consider, for Fluorochemicals touch millions of peoLUORINE IS AN ELEMENT OF MANY example, agrochemicals, where about 17% ples' lives in meaningful ways every day esmosts: It is the most reactive ofall of active materials used as pesticides and pecially in health care and quality-of-life of the elements, the most powerfungicides are based on fluorinated comproducts. At the top of a very long list: the ful oxidizing agent, and the most pounds. The manufacture of silicon chips inorganic fluorides used in drinking water electronegative. But its true relies on the wet and dry etch processes and dental products, the one out of every strength and the secret of its success lies in utilizing materials such as ultra-high-purithe compounds it forms—some of the ty H F and NF 3 . Elemental fluorine is used most stable and inert substances known to prepare UF 6 , used by the nuclear into man. These compounds have enabled a dustry for uranium enrichment. Electrical steady stream of scientific and commerutilities rely on the high dielectric strength cial advances: Staying warm and dry in a of SF 6 , also manufactured using direct eldownpour, cooking with the ease of a nonemental fluorination, for high-voltage cirstick pan, and beaming a "cavity free" smile cuit breakers and transformers. And withare all available thanks to the fluorine atom. in the chemical processing industries, Fluorine occurs naturally as a mono-isocatalysts include BF 3 and SbF5, KF is used tope 19 F 9 and is not a rare element: About as a fluorinating agent, and A1F3 is used to 0.07% ofEarth's crust is comprised of fluoprocess aluminum. rine, mosdy as the minerals fluorapatite and fluorite (CaF^, the main constituent of the Today, the innovative use and applicaore fluorspar. Although very few naturally tion of fluorine chemistry and fluorinated occurring organofluorine compounds are materials continues unbounded, especially known to exist, many man-made fluoroin growth areas of optoelectronics, elecchemicals have been developed over the tronics, life sciences, and high-performance years, all of which have fluorspar as their materials. And what's on the horizon is even starting point. The unique properties, permore exciting: Imagine "smart dust" where vasive influence, and lasting impact of these supermicrosensors allow us to gather vital compounds have given fluorine a distincdata on a scale previously unimaginable; LIFTO F F ! The National Space Centre tion as "the little atom that could." new materials capable of making more efin Leicester, England, features a Rocket fective repairs to the human body; and pharTower composed of ethylenemaceuticals customized for use, compatitetrafluoroethylene copolymer. FLUORINE AT A GLANCE bility, and delivery It's hard not to get caught up in the fuName: From the Latin fluere, flow. five active pharmaceutical products that ture potential of fluorine chemistry ReAtomic mass: 19.00. is fluorinated, and the synthetic blood subcently, following a speech I gave to an stitutes and inhalation drug delivery sysHistory: Fluorine was first identified by industry group, a chemist halfKarl W. Scheele in 1771. It was first tems that use fluorocarbons. jokingly told me, "I'm glad to see isolated in 1886 by French chemist Fluorochemicals also underthe fluorine (F) pin on your jackF. Henri Moissan. His reward was the score a wide range of commeret lapel, because without it, Nobel Prize for Chemistry in 1906. cial successes. Growth in the Occurrence: Found in fluorspar, cryoyou're not fulfilling your role as industrial and household refriga leader in the chemical induslite, and other minerals. eration and air conditioning intry" I couldn't agree more. In the Appearance: Pale yellow gas. The free dustries is based largely on the 117 years since it was first isolatelement has a characteristic odor. use of low-toxicity nonflammaTHIS ELEMENT Behavior: Fluorine is the most reactive ble, and energy-efficient fluoroed by Henri Moissan, fluorine has BROUGHT TO YOU BY element and reacts with practically all carbon fluids. Fluoropolymers become a powerful foundation HONEYWELL substances. It reacts with water to proand fluoroelastomers are used for chemical exploration, disSPECIALTY duce oxygen and ozone. Fluorine gas is widely in homes, buildings, aucovery, and innovation. W h o MATERIALS tomobiles, aerospace applicacorrosive and toxic. would have imagined that fluotions, and wherever high performance is reUses: An essential trace element for rine would serve as the foundation for so quired—performance such as excellent mammals. Fluorine and its compounds many of today's modern marvels and tothermal, flame, electrical, chemical, and sol- morrow's most promising innovations? are used in producing uranium and vent resistance and low oxygen and moismore than 100 commercial fluoroture permeability Other low-molecularNance K. Dicciani is president and CEO of chemicals. Certain fluorocarbons were weight perfluoroalkyl-based materials Specialty Materials, a strategic business group of used in air conditioning and refrigeraprovide oil-, water-, and soil-repellent surface Honeywell. She holds a PhD. in chemical engition but have been phased out because properties for textile,fiber,and paper coatneering and has more than 25 years ofexperience they damaged the ozone layer. ings; and similar materials are used as surin the chemical industry.
FLUORINE
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C&EN / SEPTEMBER 8, 2003
HTTP://WWW.CEN-ONLINE.ORG
