摘要:
To provide a method for purifying R-1234yf, whereby it is possible to efficiently remove even impurities such as R-1243zf, etc. which are difficult to separate by distillation purification, from a mixture containing R-1234yf as the main component and various impurities, such as a gas formed by reacting R-1214ya with hydrogen. The method for purifying R-1234yf comprises a step of bringing a mixture which contains R-1234yf as the main component and also contains hydrohaloalkene impurities other than R-1234yf and hydrohaloalkane impurities, into contact with a solvent that has an extraction/removal index (r), as represented by the formula r = [4 × (δD - 17.2) 2 + (δP-8.3) 2 + (δH - 2.6) 2 ] 1/2 , of at most 6.5, so as to remove at least a part of the hydrohaloalkene impurities and hydrohaloalkane impurities.
摘要:
To provide a crosslinkable fluororubber composition which can give a crosslinked rubber article excellent in flexibility at a low temperature, and the crosslinked rubber article. A crosslinkable fluororubber composition comprising a fluororubber and a compound represented by (X-) x (Z-) z Y, is crosslinked to form a crosslinked rubber article. In the formula, X is U-(CF 2 ) a O(CF 2 CF 2 O) b -, Z is R F O(CF 2 CF 2 O) c -, Y is a (x+z) valent perfluoro saturated hydrocarbon group or such a group having an etheric oxygen atom inserted between carbon atoms thereof, x is an integer of at least 3, z is an integer of at least 0, x+z is an integer of at least 3, U is a monovalent group having at least one member selected from the group consisting of an unsaturated hydrocarbon, a bromine atom and an iodine atom, R F is a C 1-20 linear perfluoroalkyl group or such a group having an etheric oxygen atom inserted between carbon atoms thereof, a is an integer of from 0 to 20, b is an integer of from 1 to 200, and c is an integer of from 3 to 200.
摘要:
In the production of 2,3,3,3-tetrafluoropropene (HFO-1234yf), formation of HFC-254eb as an excessively reduced product is suppressed. A process for producing 2,3,3,3-tetrafluoropropene, which comprises reacting a raw material compound composed of at least one of 1,1-dichloro-2,3,3,3-tetrafluoropropene and 1-chloro-2,3,3,3-tetrafluoropropene, and hydrogen, in a gas phase in the presence of a catalyst, wherein the catalyst is a palladium catalyst supported on active carbon, and the ratio of the hydrogen to the raw material compound to be introduced to a catalyst layer packed with the palladium-supporting active carbon is at most 0.7 as represented by the ratio of the number of moles of the hydrogen to the number of moles of chlorine atoms in the raw material compound (H 2 /Cl).
摘要:
Disclosed is a method for efficiently producing a fluorine-containing polymer by an aqueous emulsion polymerization using a fluorine-containing carboxylic acid compound. Specifically disclosed is a method for producing a fluorine-containing polymer, wherein a fluorine-containing monomer is emulsion-polymerized in an aqueous medium containing a fluorine-containing carboxylic acid compound using a polymerization catalyst. This a method for producing a fluorine-containing polymer is characterized in that the pH of the aqueous medium during the polymerization is not more than 4.
摘要:
The object is to provide a process for producing highly pure 2,3,3,3-tetrafluoropropene, whereby formation of 3,3,3-trifluoropropene is suppressed. A process for producing 2,3,3,3-tetrafluoropropene, which comprises reacting a raw material compound composed of 1,1-dichloro-2,3,3,3-tetrafluoropropene and/or 1-chloro-2,3,3,3-tetrafluoropropene, and hydrogen in a gas phase in a reactor having a catalyst layer packed with a catalyst-supporting carrier, while maintaining the maximum temperature of the catalyst layer to be at most 130°C, to obtain formed gas containing 2,3,3,3-tetrafluoropropene, and then, contacting the formed gas discharged from the reactor, with alkali at a temperature of at most 100°C.