Bayer Aktiengesellschaft

Roland Kleinstuck

Hans-Dieter Block

Torsten Groth

Winfried Joentgen

Hermann Sicius

Hermann Uhr

Lutz Heuer

Michael Immenkeppel

Hans-Heinrich Moretto

Rolf Wiedermann

Uwe Arndt

Wolfgang Ohlendorf

Peter Schmidt

Christoph Holzner

Herbert Kallfass

Gerhard Bohnsack

Herbert Odenbach

Winfreid Joentgen

Cornelia Lensch

Sulfonic acid group-containing polyaspartic acid derivatives, some of which are novel, having repeating units of the structures I and II ##STR1## in which ##STR2## are suitable for water treatment and as a detergent additive.

Sulfonic acid group-containing polyaspartic acid derivatives, use

This invention relates to an improved process for the production of 2-phosphono-butane-1,2,4-tricarboxylic acid (PBTC) and the alkali metal salts thereof, in which process dialkyl phosphite, preferably dimethyl or diethyl phosphite, and ethene-1,2-dicarboxylic acid dialkyl ester, in particular the dimethyl or diethyl ester of maleic acid and/or fumaric acid, are initially reacted in the presence of a basic catalyst to yield a phosphonosuccinic acid tetraalkyl ester, the resultant ester is thereupon reacted without further working up with acrylic acid alkyl ester, preferably methyl or ethyl acrylate, in the presence of an alkaline catalyst and the reaction product obtained in this manner is saponified without further working up to yield PBTC or the alkali metal salts thereof. The product when mixed with bleaching lye exhibits reduced chlorine depletion.

Production of 2-phosphonobutane-1,2,4-tricarboxylic acid and the alkali

An improved composition for water treatment and for alkaline cleaning contains polyaspartic acid or a derivative thereof and a polycarboxylic acid.

Composition for water treatment containing polyaspartic acidora

An improved composition for water treatment and for alkaline cleaning contains polyaspartic acid or a derivative thereof and a phosphonic acid.

Water treatment/cleaning composition comprising polyaspartic acid or

Sulfonic acid group-containing polyaspartic acid derivatives, some of which are novel, having repeating units of the structures I and II ##STR1## in which R.sup.1 has the meaning given in the description, are suitable for water treatment and as a detergent additive.

The present invention relates to a process for the preparation of alkali metal salts of 2-phosphonobutane-1,2,4-tricarboxylic acid, characterized in that 2-phosphonobutane-1,2,4-tricarboxylic acid penta-alkyl esters or partial esters are reacted with an aqueous alkali metal hydroxide solution in a ratio of from 0.5 to 0.76 mol, preferably from 0.6 to 0.7 mol of alkali metal hydroxide per mol of ester function at temperatures from 20.degree. to 200.degree. C. in a one-shot process.

Process for the preparation of alkali metal salts of

The present invention relates to a process for eliminating 1-phosphono-1-carboxycyclopentan-3-one (ketone) from, or reducing its content in, an aqueous solution of 2-phosphonobutane-1,2,4-tricarboxylic acid, characterized in that the solution is adjusted to a pH value of &gt; 6 using an aqueous inorganic base, particularly sodium hydroxide, and aqueous bleaching liquor is subsequently added in a molar ratio of NaOCl to ketone of &gt;5:1.

Process for eliminating 1-carboxy-1-phosphonocyclopentan-3-one from, or

A process for the treatment of cooling waters, particularly in thermal power stations, without or--optionally--with partial acid decarbonization of the make up water, the improvement wherein the make up water is mechanically coarse-clarified and the hardness is then stabilized with scale inhibitors. The scale inhibitors are then removed from the blow down and are optionally recovered.

Process for treating cooling water

This invention relates to an improved process for the continuous production of 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTC) and alkali metal salts thereof, in which dialkylphosphite, and ethene-1,2-dicarboxylic acid dialkyl ester, are reacted in the presence of a basic catalyst to form phosphonosuccinic acid tetraalkyl ester, the ester thus obtained is directly reacted with alkyl-acrylate, in the presence of an alkaline catalyst and the reaction product thus obtained is directly hydrolyzed to PBTC or alkali metal salts thereof.

Process for the continuous production of

Flame retardant isocyanate addition products are made by reacting an isocyanate with a compound selected from the group consisting of 1-phosphonoethane-2-carboxylic acid-tri-C.sub.1 -C.sub.4 -alkyl esters, 1-phosphonopropane-2-carboxylic acid-tri-C.sub.1 -C.sub.4 -alkyl esters and mixtures thereof. Known isocyanate-reactive compounds, blowing agents, catalysts, additives and auxiliary agents may optionally be included in the reaction mixture. These flame retardant products are useful in construction applications such as insulation panels for roof insulation.

Isocyanate addition products and a process for their production

Water is conditioned by adding thereto a corrosion-inhibiting, concretion inhibiting, precipitation retarding, deflocculating, dispersing or fluidifying amount of an acid of the formula ##STR1## in which R.sup.1 and R.sup.2, independently of one another, represent hydrogen where a or b=1, or where a or b=0 represent an optionally substituted alkyl radical with 1-8 carbon atoms or an optionally substituted phenyl radical,

Propane-1,3-diphosphonic acids for conditioning water

In the production of phosphorous or phosphonous acid ester chlorides of the formula

Catalyzed production of phosphorous and phosphonous acid ester chlorides

In the preparation of an aminoalkylsilane of the formula

Growing community of inventors

Bergisch Gladbach, Germany

Roland Kleinstuck