Organic fluorine compound

In 1896, the synthesis of ethyl fluoride acetate marked the beginning of the study of organic fluorine chemistry, it has been exactly a century. In the meantime, several historic breakthrough has greatly promoted the development of organic fluorine chemistry, such as the 1930s the application of freon used in the refrigeration industry, the implementation of the Manhattan Project during World War II and the 1950s high physiological activity of the synthesis of 5-fluorine urea. China is rich in fluorine resources, it has proven reserves of fluorite about a quarter of the world's total reserves, but until the 1950s, fluorine chemistry in China is still a blank. At the end of 50s, due to changes in the international situation, China began to develop its own atomic energy technology, the need for a number of special fluoride materials, since then, the study of organic fluorine chemistry in China has been started. Shanghai Institute of organic chemistry, Chinese Academy of Sciences, due to the excellent work in the basic research of organic fluorine chemistry, has been hailed as the "fluorine chemistry of Shanghai" by the international fluorine chemical industry.

The organic fluorine compound, also known as fluorocarbon compounds, i.e. containing C-F bond in the molecular structure, such as tetrafluoroethylene (CF2 = CF2), all the hydrogen atoms in the hydrocarbon molecules replaced by fluorine atoms, which are called the whole fluorine compounds. Fluorine is the most electronegative, the highest degree of oxidation of atoms in the periodic table, and therefore less susceptible to oxidation cleavage fluoropolymer, and the radius of the fluorine atom is almost equal to half of the C-C bond, so the fluorine atom can be arranged closely around the carbon atom to form a barrier to the C-C bond to ensure its chemical stability. The bond energy of C-F bond is extremely high, so the organic fluorides have good thermal stability, chemical stability and oxidation resistance. There are many fluorine-containing compounds, such as halothane, anti-cancer drugs, fluorouracil, fluphenazine, haloperidol,etc.

Organic fluorine compounds can be broadly divided into three categories.
①The fluorine alkyl chloride, mainly used in refrigerants and aerosol (see Freon entry).
② Perfluorinated hydrocarbons and perfluorinated ethers, acids, tertiary amines, wherein the perfluoroalkanes having high chemical stability. Such as perfluoroheptane are lubricant which resistant to oxidation and high temperature; perfluoroolefins such as tetrafluoroethylene is monomer of PTFE; the saturated organic compounds of perfluorodecalin and perfluorinated tertiary amines emulsified from the white emulsion (known as white blood), successful as a blood substitute for clinical.
③ Fluorine-containing polymer can excellent high temperature, low temperature resistance, chemical corrosion. Such as PTFE known as the king of plastic commonly, and perfluoro rubber (called Viton) copolymerized by vinylidene fluoride and HFP, etc., widely used in national defense, aerospace, petroleum, chemicals, machinery and other sectors, such as Gordon month clothing fire-proof, corrosion-resistant pipes and containers, clothing, wear pads, sliding pads of road and rail and bridges, and gaskets etc..

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