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Bis(trifluoromethyl)peroxide
Bis(trifluoromethyl)peroxide (BTP) is a fluorocarbon derivative first produced by Frédéric Swarts. It has some utility as a radical initiator for polymerisation reactions. BTP is unusual in the fact that, unlike many peroxides, it is a gas, is non-explosive, and has good thermal stability.Ellingboe, E.K.; McCleiland A.L. Polymerization initiator. US 3202718, June 20, 1960 History BTP was first synthesised by an electrolysis reaction using aqueous solutions containing trifluoroacetate ion but only in trace amounts. BTP was one of the by-products formed during trifluoromethylation reactions carried out by Swarts. Later it was discovered that BTP had some unusual properties and so more economically viable synthesis routes were sought. An early example was that of Porter and Cady, who were able to achieve a conversion rate of around 20-30% at atmospheric pressure and up to 90% at elevated pressure in an autoclave. Synthesis and reaction Present methods of the synthesis of BTP inv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Highly Toxic Gases
Many gases have toxic properties, which are often assessed using the LC50 (median lethal concentration) measure. In the United States, many of these gases have been assigned an NFPA 704 health rating of 4 (may be fatal) or 3 (may cause serious or permanent injury), and/or exposure limits ( TLV, TWA/PEL, STEL, or REL) determined by the ACGIH professional association. Some, but by no means all, toxic gases are detectable by odor, which can serve as a warning. Among the best known toxic gases are carbon monoxide, chlorine, nitrogen dioxide and phosgene. Definitions *Toxic: a chemical that has a median lethal concentration (LC50) in air of more than 200 parts per million (ppm) but not more than 2,000 parts per million by volume of gas or vapor, or more than 2 milligrams per liter but not more than 20 milligrams per liter of mist, fume or dust, when administered by continuous inhalation for 1 hour (or less if death occurs within 1 hour) to albino rats weighing between 200 and 3 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluorocarbon
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. Its st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frédéric Swarts
Frédéric Jean Edmond Swarts (2 September 1866 – 6 September 1940) was a Belgian chemist who prepared the first chlorofluorocarbon, CF2Cl2 (Freon-12) as well as several other related compounds. He was a professor in the civil engineering at the University of Ghent. In addition to his work on organofluorine chemistry, he authored the textbook "Cours de Chimie Organique."Frédéric Swarts "Cours de Chimie Organique" Librairie Scientifique, A. Hermann (Paris), 1908. He was a son of Theodore Swarts (chemist, *1839 Antwerpen; †1911 Kortenberg, Belgium) and a colleague of Leo Baekeland Leo Hendrik Baekeland ( , ; November 14, 1863 – February 23, 1944) was a Belgian chemist. Educated in Belgium and Germany, he spent most of his career in the United States. He is best known for the inventions of Velox photographic paper .... References * {{DEFAULTSORT:Swarts, Frederic 20th-century Belgian inventors Belgian chemists 1866 births 1940 deaths Academic staff of Ghen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ministry Of Health, Labour And Welfare
The is a cabinet level ministry of the Japanese government. It is commonly known as in Japan. The ministry provides services on health, labour and welfare. It was formed with the merger of the former Ministry of Health and Welfare or and the Ministry of Labour or . The Minister of Health, Labour and Welfare is a member of the Cabinet and is chosen by the Prime Minister, typically from among members of the Diet. Organization The ministry contains the following sections as of 2019: * The Minister's Secretariat (including the Statistics and Information Department) * The Health Policy Bureau * The Health Service Bureau * Pharmaceutical and Food Safety Bureau (including the Food Safety Department) * The Labour Standards Bureau (including the Industrial Safety and Health Department, Workers Compensation Department, and Workers' Life Department) * The Employment Security Bureau (including the Employment Measures for the Elderly and Persons with Disabilities Department) * The H ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bis(trifluoromethyl) Disulfide
Bis(trifluoromethyl) disulfide (TFD) is a fluorinated organosulfur compound that was used as a fumigant. It is also an intermediate in the synthesis of triflic acid. It is a volatile liquid that is extremely toxic by inhalation. Synthesis TFD can be produced by reaction of perchloromethyl mercaptan or thiophosgene with sodium fluoride. Toxicity TFD is extremely toxic by inhalation. TFD is a powerful pulmonary agent that can cause severe pulmonary edema. TFD is about half as toxic as perfluoroisobutene. See also * Dimethyl(trifluoromethylthio)arsine * Perchloromethyl mercaptan *Thiophosgene *Perfluoroisobutene *Phosgene Phosgene is an organic chemical compound with the formula . It is a toxic, colorless gas; in low concentrations, its musty odor resembles that of freshly cut hay or grass. It can be thought of chemically as the double acyl chloride analog of ... References Organic disulfides Trifluoromethylthio compounds Pulmonary agents Fumigants {{Organoha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Peroxides
In organic chemistry, organic peroxides are organic compounds containing the peroxide functional group (). If the R′ is hydrogen, the compounds are called hydroperoxides, which are discussed in that article. The O−O bond of peroxides easily breaks, producing free radicals of the form (the dot represents an unpaired electron). Thus, organic peroxides are useful as radical initiator, initiators for some types of polymerization, such as the Acrylic resin, acrylic, unsaturated polyester, and vinyl ester resins used in glass-reinforced plastics. methyl ethyl ketone peroxide, MEKP and benzoyl peroxide are commonly used for this purpose. However, the same property also means that organic peroxides can explosively combust. Organic peroxides, like their inorganic counterparts, are often powerful bleaching agents. Types of organic peroxides Organic peroxides are classified (i) by the presence or absence of a hydroxyl () terminus and (ii) by the presence of alkyl vs acyl substituents. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trifluoromethyl Compounds
The trifluoromethyl group is a functional group that has the formula In science, a formula is a concise way of expressing information symbolically, as in a mathematical formula or a ''chemical formula''. The informal use of the term ''formula'' in science refers to the general construct of a relationship betwe ... . The naming of is group is derived from the methyl group (which has the formula ), by replacing each hydrogen atom by a fluorine atom. Some common examples are trifluoromethane , 1,1,1-trifluoroethane , and hexafluoroacetone . Compounds with this group are a subclass of the organofluorines. Properties The trifluoromethyl group has a significant electronegativity that is often described as being intermediate between the electronegativities of fluorine and chlorine. For this reason, trifluoromethyl-substituted compounds are often strong acids, such as trifluoromethanesulfonic acid and trifluoroacetic acid. Conversely, the trifluoromethyl group lowers the basicity of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
