Hoechst Aktiengesellschaft

Hubert Seitz

Rudolf Aigner

Wolfgang Neumann

Reinhard Vybiral

Bernd Papenfuhs

Heinz Hoffmann

Andreas Gallas

Rainer Muller

Karlheinz Stahl

Guillermo Maier

Gunther Hertel

In the process described, purification and improvement in odor of, in particular, fatty alkyldimethylamines is achieved by exposing, in the liquid phase, the tertiary amine to be treated to a vacuum or an inert gas stream. By means of the process according to the invention, in a relatively short time and in a simple and economical manner, a tertiary fatty alkylmethylamine is obtained which is essentially trimethylamine-free and improved in odor.

Process for purifying tertiary fatty alkylmethylamines

The process described relates to the preparation of aqueous betaine solutions by reaction of a tertiary amine with an .omega.-monohalocarboxylic acid, preferably monochloroacetic acid, and an alkali metal hydroxide in the presence of water, which solutions are said to be highly pure particularly in respect of the tertiary starting amine and .omega.-monohalocarboxylic acid. This is achieved by first reacting the three reaction components in a certain molar ratio with the aim of obtaining a betaine solution which comprises only a tolerated amount of starting amine. This aqueous betaine solution is then treated with a sulfonating agent, preferably with an alkali metal sulfite, alkali metal pyrosulfite or alkali metal bisulfite, for conversion of the .omega.-monohalocarboxylic acid present into the corresponding sulfocarboxylic acid, which is not troublesome. The process described is simple to carry out and leads to the highly pure aqueous betaine solutions mentioned.

Process for the preparation of pure aqueous betaine solutions

A process is described for the preparation of aqueous solutions of betaines of the formula ##STR1## in which: R.sup.1 is an alkyl radical having 6 to 22 carbon atoms or is a radical of the formula R'CONH(CH.sub.2).sub.z --, in which R' has the meaning of R.sup.1 and z is 2, 3 or 4, R.sup.2 is an alkyl radical having 1 to 4 carbon atoms or is a radical of the formula --(CH.sub.2).sub.m --OH, in which m is 1, 2 or 3, R.sup.3 is an alkyl radical having 1 to 4 carbon atoms or is a radical of said formula --(CH.sub.2).sub.m --OH and y is 1, 2 or 3. The aqueous betaine solutions are prepared by quaternization of the corresponding tertiary amines with an .omega.-halocarboxylic acid and with an alkali metal hydroxide in the aqueous phase. The quaternization is carried out continuously in two or three stirred tanks arranged in a cascade, defined process characteristics being maintained in each tank. Using the novel process, aqueous betaine solutions are obtained in high yield and purity in a simple manner.

Process for the preparation of aqueous betaine solutions

The concentrate contains an ammonium compound which carries a longer-chain and a medium-chain substituent on the nitrogen atom, and both the other substituents are either hydrogen atoms, methyl, ethyl or .beta.-hydroxyethyl. The medium-chain substituent should have half the carbon atoms of the longer-chain substituent or one or two carbon atoms less than half. Instead of an ammonium compound, a mixture of several ammonium compounds can also be present which on average corresponds to the formula described above. In addition to water, the concentrate can also contain 0 to 10% by weight, relative to the total amount of the ammonium compounds, of one or more compounds which are selected from amongst alkali metal salts, ammonium salts, aliphatic amines, alkyl or alkenyl esters or olefins having 6 to 20 carbon atoms. The concentrates have a low viscosity, which makes them easily pumpable, transportable and meterable. They can be diluted without noticeable increase in viscosity and contain virtually no combustible solvents.

Water-containing concentrate of at least one alkyl- or

Concentrated, aqueous, colloidal dispersions of tetrafluoroethylene polymers having a polymer solids content of 25 to 70% by weight, which comprise, as the dispersion stabilizer, an amine oxide of the formula ##STR1## in which R.sup.1 is an alkyl radical having 6 to 22 carbon atoms or a mixture of such alkyl radicals and R.sup.2 is an alkyl radical having 1 to 22 carbon atoms or a mixture of such alkyl radicals, and in which R.sup.1 and R.sup.2 are identical or different and 50 to 0% by weight of the alkyl radicals R.sup.1 and R.sup.2 can be replaced by alkenyl radicals having 6 to 22 carbon atoms and having 1 to 3 C.dbd.C double bonds, are obtained by concentration with addition of these dispersion stabilizers. The dispersions are used for impregnating yarns and textile sheet-like structures.

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Burgkirchen, Germany

Hubert Seitz