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US 5,288,908 AGranted
Process for the preparation of fluorine containing monomers
AssigneeHoechst Aktiengesellschaft
InventorsJurgen Lau, Gunter Siegemund, Freimund Rohrscheid
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AssigneeHoechst Aktiengesellschaft
InventorsJurgen Lau, Gunter Siegemund, Freimund Rohrscheid
Estimating the term…
Compounds of the formula ##STR1## in which X represents hydrogen, --NO.sub.2 or --NH.sub.2 and Y represents --CH.sub.3, --COOH, --CONH.sub.2, --NH.sub.2 or --N.dbd.N--Z, in which the group --Z is ##STR2## with the proviso that if Y represents the group --N.dbd.N--Z, X is only --NO.sub.2, and if Y represents the group --CH.sub.3, X is only hydrogen, are described. A compound of the formula ##STR3## the preparation of which in a multi-stage process, in which the compounds of the general formula (I) are also obtained, is described, is preferred. The resulting 3,4'-diamino compound is suitable for the preparation of polycondensates and shaped articles, films and fibers of high heat resistance.
A process for the preparation of the compound of the formula (II) ##STR6## in a multi-stage process, which comprises 1a) subjecting 2-(4-methylphenyl)hexafluoropropan-2-ol to a condensation reaction with benzene in the presence of hydrogen fluoride or
Dependencies are inferred from the claim text.
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Polyimides; Polyester-imides; Polyamide-imides; Polyamide acids or similar polyimide precursors: comprising halogen-containing substituents
By condensation reactions: of hydrocarbons and halogenated hydrocarbons
Containing six-membered aromatic rings: containing fluorine
By oxidation: with halogen-containing compounds which may be formed in situ
Term ended 22 Feb 2011 (estimated)
USPTO file history isn’t available for this patent, so only indexed dates are shown.
The invention relates to fluorine-containing monomers and their preparation, in particular 2-(3-aminophenyl)-2-(4-aminophenyl)hexafluoropropane, a novel fluorine-containing monomer for polycondensates of high heat resistance, such as polyamides and polyamides.
It is known that transparent polymers of high heat stability can be prepared from 2,2-bis(3-aminophenyl) hexafluoropropane and 2,2-bis(4-aminophenyl)hexafluoropropane (U.S. Pat. No. 3,356,648, DE-OS 3,526,010 and U.S. Pat. No. 4,645,824). On the basis of the above properties, is these polymers are used as high quality materials, for example in the aircraft and electronics industries.
The object was based on preparing a partly fluorinated diamine with which polycondensates which combine the properties of the polycondensates based on the above-mentioned structurally isomeric diamino compounds can be obtained.
a) 1,290 g of 2-(4-methylphenyl)hexafluoropropan-2-ol and 780 g of benzene were initially introduced into a 5 1 steel autoclave and 1,500 g of anhydrous hydrogen fluoride were pumped into the closed autoclave. The reaction mixture was heated at 170.degree.-175.degree. C. for 64 hours, while stirring. When the reaction had ended, the hydrogen fluoride was gassed off at 80.degree. C. and the liquid product was then washed twice with water, dried over calcium chloride and subjected to fractional distillation. Boiling point 135.degree.-136.degree. C./1.4 mbar. Amount weighed: 1,424 g (89.5% of theory).
C.sub.16 H.sub.12 F.sub.6 calculated: C, 60.38%; H, 3.77%; F, 35.85%; molecular weight: 318 found: C, 60.50%; H, 3.70%; F, 35.80%.
b) 244 g of 2-phenylhexafluoropropan-2-ol, 368 g of toluene and 180 g of anhydrous hydrogen fluoride were combined in a 1 l V4A steel autoclave with a stirrer. The reaction mixture was then stirred at 175.degree. C. for 65 hours. After cooling to 80.degree. C., the hydrogen fluoride was gassed off. The crude product was washed twice with water, dried over calcium chloride and subjected to fractional distillation. Boiling point 82.degree. C./0.05 mbar. 67 g 21% of theory.