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A work of FSUE Russian Scientific Center "Applied Chemistry" in the field of synthesis of new heat-transfer agents and surfactants V. Barabanov, B. Maximov, V. Matalin, D. Moldavsky, K. Serushkin, G. Kaurova Federal State Unitary Enterprise Russian Scientific Center
"Applied chemistry", FSUE RSC "Applied chemistry" has invented the technology of synthesis of perfluorinated
dielectric-heat transfers (PFDH) with wide range of application, working in different temperature intervals depending on their boiling points,
freezing points and other physical and chemical characteristics. These compounds obtain their properties such as chemical and biological inertness, thermophysical, dielectrical and other properties due to complete replacement of hydrogen atoms in their molecule for fluorine. In Russia the technology of electrochemical synthesis of fluorine compounds was developed most widely in FSUE RSC "Applied chemistry". The surfactant "chromine" for chrome plating tubs and inert dielectric liquids ( perfluorodibutyl ether, perfluorotriethylamine, perfluorotributylamine) was synthesized and to apply in pilot-industrial plants. Detailed investigation of main parameters of electrolysis, the development of continuous electrochemical fluorination method (long-term and stable electrolysis) and process implementation preceded the creation of pilot-industrial plants. The variety of laboratory and industrial electrolyzes is
developed, electrolysis parameters, influencing the power output of base
compounds are defined. The creation of two surface-active material classes and compositoins on their basis– flactonits and epilames (efrens) was the result of long term researches, developed in FSUE RSC "Applied chemistry". Flactonits are used in galvanic
processes, fire-fighting, microelectronics, chemical and photographic industries.. The range of operating concentrations of
flactonits in different technological processes is 0,5 – 1000 mg per 1 liter. Table 1. Perfluorinated dielectric-heat-transfers, developed in FSUE RSC "Applied chemistry"
We will discuss in detail about some perfluorinated organic compounds used in industry which synthesis method was recently researched in the our laboratory. 1.Surfactants. We have developed the method of obtaining of the following surface active
materials: methylethanolamine salt of perfluorooctylsulfo-acid
and ethylethanolamine salt of perfluorooctylsulfo-acid.
Perfluorooctanesulfofluoride, which is the feed stock for the synthesis of discussed
surfactants was synthesized by electrochemical fluorination method in the medium of liquid non-aqueous anhydrous hydrogen fluoride. 2.Perfluoroethanesulfofluoride Among important practical applications of electrochemical fluorination method there is synthesis of perfluoroalkanesulfofluorides and perfluoroalkanesulfo-acids. Such acids are used as super acids in the organic synthesis and their salts, as intermediates in the synthesis of surfactants. Perfluoroethanesulfofluoride is used during the synthesis of bis(pentafluoroethanesulfonyl)imide ,which there is the perspective material for obtaining electrolytes for lithium-ions batteries. It was shown that ethanesulfofluoride was the most convenient
initial substance for the synthesis of perfluoroethanesulfofluoride . The technology of
ethanesulfofluoride producing using halogen exchange at catalyst was
developed too. 3. Perfluoropropylpentyl ether Perfluorinated ethers are similar in their properties with perfluorocarbons, but unlike last mentioned they have lower freezing point and lesser viscosity. It greatly expands their field of application in different areas of technics. In Russia perfluorodibutyl ether was commercially produced , as perspective dielectric and heat transfer . However the technology of its obtaining included the addition of n-butylmercaptan as compound for anti-resinification. It using is not permitted now from toughened ecological requirements. The technology of obtaining of perfluoropropylpentyl ether having analogous properties with perfluorodibutyl ether was developed in FSUE RSC "Applied chemistry". This technology excludes using of mercaptan. Moreover, because of the fact, that partly fluorinated ethers are used as basic compound, the yield of final product and efficiency of the process greatly increase. 4. Perfluoromethylcyclohexane
The development of perfluorinated cyclic paraffin's obtaining technology is an
important practical task, because fluorocarbons have unusual combination of physical and chemical properties: they have relatively low boiling points, which do not correspond with their molecular weight values, low critical temperatures and pressures, high liquid densities and coefficients of expansion, noticeably lower surface tensions and refraction coefficients than any other liquid has. The condensability of these liquids is higher than the one of most others and therefore
the sonic speeds are really low. These compounds have good electric properties.
Perfluoroalkanes have unique physical and chemical stability. Fluorocarbons are considered "almost nontoxic" from biochemical point of view, that means the lowest coefficient of toxicity (6).
1. Abe T. Nagase S. Chapter 1. Electrochemical fluorination ( Simons process) as a route to perfluorinated organic compounds of industrial interest. Ed. R. E. Banks 19-43, (1982).
4. R.D. Danielson and J.W. Sargent, Pat. USA 3028321, C25B 3/08, îïóá.1962 ã). 5. The Role of adsorption in electrochemical perfluorination of alkylsulfofluorides. G. Cauquis, B.Keita and G.Pierre. J. Electroanal. Chem., 100 (1979) 205 – 215.3). 6. Slinn D.S.L., Green S.W. Chapter 2. Fluorocarbon Fluids for use in the electronic industry. 45-81, (1982). |
