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Krytox
Krytox, a registered trademark of The Chemours Company, is a group of colorless synthetic lubricants (oils and greases) with a variety of applications. Invented by researchers at DuPont, Krytox oils are fluorocarbon ether polymers of polyhexafluoropropylene oxide, with a chemical formula: F−(CF(CF3)−CF2−O)''n''−CF2CF3, where the degree of polymerization, ''n'', generally lies within the range of 10 to 60. These compounds are collectively known by many names including perfluoropolyether (PFPE), perfluoroalkylether (PFAE), and perfluoropolyalkylether (PFPAE). A unique identifier is their CAS registry number, 60164-51-4. In addition to PFPE, Krytox grease also contains telomers of PTFE and in fact was designed as a liquid or grease form of PTFE. It is thermally stable, nonflammable (even in liquid oxygen), and insoluble in water, acids, bases, and most organic solvents. It is nonvolatile and useful over a broad temperature range of or higher. Its high resistance to ionizi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluoropolymers
A fluoropolymer is a fluorocarbon-based polymer with multiple carbon–fluorine bonds. It is characterized by a high resistance to solvents, acids, and Base (chemistry), bases. The best known fluoropolymer is polytetrafluoroethylene under the brand name "Teflon," trademarked by the DuPont, DuPont Company. History In 1938, polytetrafluoroethylene (DuPont brand name Teflon) was discovered by accident by a recently hired DuPont Ph.D., Roy J. Plunkett. While working with tetrafluoroethylene gas to develop refrigerants, he noticed that a previously pressurized cylinder had no pressure remaining. In dissecting the cylinder, he found a mass of white solid in a quantity similar to that of the tetrafluoroethylene gas. It was determined that this material was a new-to-the-world polymer. Tests showed the substance was resistant to corrosion from most acids, bases and solvents and had better high temperature stability than any other plastic. By early 1941, a crash program was making substa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grease (lubricant)
Grease is a solid or semisolid lubricant formed as a dispersion of thickening agents in a liquid lubricant. Grease generally consists of a soap emulsified with mineral or vegetable oil. A common feature of greases is that they possess high initial viscosities, which upon the application of shear, drop to give the effect of an oil-lubricated bearing of approximately the same viscosity as the base oil used in the grease. This change in viscosity is called shear thinning. Grease is sometimes used to describe lubricating materials that are simply soft solids or high viscosity liquids, but these materials do not exhibit the shear-thinning properties characteristic of the classical grease. For example, petroleum jellies such as Vaseline are not generally classified as greases. Greases are applied to mechanisms that can be lubricated only infrequently and where a lubricating oil would not stay in position. They also act as sealants to prevent the ingress of water and incompressible ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexafluoropropylene Oxide
Hexafluoropropylene oxide (HFPO) is an intermediate used in industrial organofluorine chemistry; specifically it is a monomer for fluoropolymers. This colourless gas is the epoxide of hexafluoropropylene, which is a fluorinated analog of propylene oxide, HFPO is produced by Chemours and 3M and as a precursor to the lubricant Krytox and related materials. It is generated by oxidation of perfluoropropylene, e.g. with oxygen as well as other oxidants. Reactivity Fluoride catalyzes the formation of perfluorinated polyethers such as Krytox. The initial step entails nucleophilic attack at the middle carbon to give the perfluoropropoxide anion, which in turn attacks another monomer. This process generates a polymer terminated by an acyl fluoride, which is hydrolyzed to the carboxylic acid which is decarboxylated with fluorine. The net polymerization reaction can be represented as: : Upon heating above 150 °C, HFPO decomposes to trifluoroacetyl fluoride and difluorocarbene: : The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemours
The Chemours Company (, ) is an American chemical industry, chemical company that was founded in July 2015 as a Corporate spin-off, spin-off from DuPont. It has its corporate headquarters in Wilmington, Delaware, United States. Chemours is the manufacturer of Polytetrafluoroethylene, Teflon, the brand name of polytetrafluoroethylene (PTFE), known for its anti-stick properties. It also produces titanium dioxide and refrigerant, refrigerant gases. History In October 2013, DuPont announced that it was planning to spin off its "speciality chemicals, performance chemicals" business into a new publicly traded company in mid-2015. DuPont filed its initial Form 10-12B, Form 10 with the U.S. Securities and Exchange Commission, SEC in December 2014 and announced that the new company would be called "The Chemours Company." The name is a portmanteau of the words chemical and Nemours, a nod to DuPont's full name, E. I. du Pont de Nemours & Co. The company's CC ticker symbol, is also a play o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perfluoropolyether
Perfluoropolyethers (PFPEs) are a class of organofluorine compound. Some types are synthetic liquid lubricants that have been used in the aerospace industry for over 30 years. The main properties of PFPE are being temperature resistant between and (depending on specific composites), having very low outgassing compared to other fluids (vapour pressure of ) and having a dielectric strength of around 15.7 MV/m. Perfluoropolyethers consists of a polymer chain in which monomers consisting of perfluoro-alkyl groups are joined by ether linkages. The bonds between carbon and oxygen or fluorine are strong. Perfluoropolyethers are a type of PFAS. The thermal and chemical stability of PFPEs along with a vapor–liquid equilibrium of 230 °C when mixed with the right composites make it a suitable candidate for vapor phase soldering technologies. History Perfluoropolyethers were developed in the early 1960s for the USAF, who needed a lubricant that would not react with liquid or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liquid Oxygen
Liquid oxygen, sometimes abbreviated as LOX or LOXygen, is a clear cyan liquid form of dioxygen . It was used as the oxidizer in the first liquid-fueled rocket invented in 1926 by Robert H. Goddard, an application which is ongoing. Physical properties Liquid oxygen has a clear cyan color and is strongly paramagnetic: it can be suspended between the poles of a powerful horseshoe magnet. Liquid oxygen has a density of , slightly denser than liquid water, and is cryogenic with a freezing point of and a boiling point of at . Liquid oxygen has an expansion ratio of 1:861 and because of this, it is used in some commercial and military aircraft as a transportable source of breathing oxygen. Because of its cryogenic nature, liquid oxygen can cause the materials it touches to become extremely brittle. Liquid oxygen is also a very powerful oxidizing agent: organic materials will burn rapidly and energetically in liquid oxygen. Further, if soaked in liquid oxygen, some materials su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluorocarbons
Fluorocarbons are chemical compounds with carbon-fluorine bonds. Compounds that contain many C-F bonds often have distinctive properties, e.g., enhanced stability, volatility, and hydrophobicity. Several fluorocarbons and their derivatives are commercial polymers, refrigerants, drugs, and anesthetics. Nomenclature Perfluorocarbons or PFCs, are organofluorine compounds with the formula CxFy, meaning they contain only carbon and fluorine. The terminology is not strictly followed and many fluorine-containing organic compounds are also called fluorocarbons. Compounds with the prefix perfluoro- are hydrocarbons, including those with heteroatoms, wherein all C-H bonds have been replaced by C-F bonds. Fluorocarbons includes perfluoroalkanes, fluoroalkenes, fluoroalkynes, and perfluoroaromatic compounds. Perfluoroalkanes Chemical properties Perfluoroalkanes are very stable because of the strength of the carbon–fluorine bond, one of the strongest in organic chemistry. It ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymer Fume Fever
__NOTOC__ Polymer fume fever or fluoropolymer fever, also informally called Teflon flu, is an inhalation fever caused by the fumes released when polytetrafluoroethylene (PTFE, known under the trade name Teflon) reaches temperatures of 300 °C (572 °F) to 450 °C (842 °F). Fever When PTFE is heated above 450 °C the pyrolysis products are different and inhalation may cause acute lung injury. Symptoms are flu-like (chills, headaches and fevers) with chest tightness and mild cough. Onset occurs about 4 to 8 hours after exposure to the pyrolysis products of PTFE. A high white blood cell count may be seen and chest x-ray findings are usually minimal. The polymer fumes are especially harmful to certain animals whose breathing, optimized for rapidity, allows in toxins which are excluded by human lungs. Fumes from Teflon in very high heat are fatal to parrots Parrots (Psittaciformes), also known as psittacines (), are birds with a strong curved beak, u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solvay S
Solvay may refer to: Companies and organizations * Solvay Brussels School of Economics and Management, Brussels, Belgium * Solvay Institute of Sociology, Brussels, Belgium, part of the Université Libre de Bruxelles * Solvay Process Company (1880–1985), a former U.S. company that employed the Solvay process * Solvay S.A., an international chemicals and plastics company founded by Ernest Solvay Places * Solvay, New York, a village in New York, United States * Mount Solvay, part of Belgica Mountains in Queen Maud Land, Antarctica * Solvay Mountains, Brabant Island, off the coast of Antarctica Buildings * Solvay Castle, La Hulpe, Belgium * Hôtel Solvay, a town house in Brussels, Belgium * Solvay Hut, a mountain hut on the Matterhorn, Switzerland People * Ernest Solvay (1838–1922), Belgian chemist, inventor of the Solvay process * Lucien Solvay (1851–1950), Belgian journalist, art historian, and poet * Paolo Solvay, pseudonym of Luigi Batzella (1924–2008), Italia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ionizing Radiation
Ionizing (ionising) radiation, including Radioactive decay, nuclear radiation, consists of subatomic particles or electromagnetic waves that have enough energy per individual photon or particle to ionization, ionize atoms or molecules by detaching electrons from them. Some particles can travel up to 99% of the speed of light, and the electromagnetic waves are on the high-energy portion of the electromagnetic spectrum. Gamma rays, X-rays, and the higher energy vacuum ultraviolet, ultraviolet part of the electromagnetic spectrum are ionizing radiation; whereas the lower energy ultraviolet, visible light, infrared, microwaves, and radio waves are non-ionizing radiation. Nearly all types of laser light are non-ionizing radiation. The boundary between ionizing and non-ionizing radiation in the ultraviolet area cannot be sharply defined, as different molecules and atoms ionize at Ionization energies of the elements (data page), different energies. The energy of ionizing radiation starts ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
