WO1996004332A1

WO1996004332A1 - Process for preparing polymers with hydroxamic acid, hydroxamic acid ether and/or hydrazide groups in the side chain and their use

Info

Publication number: WO1996004332A1
Application number: PCT/EP1995/002891
Authority: WO
Inventors: Thomas Greindl; Elisabeth Kappes; Alfred Oftring; Alexander Kud; Richard Baur; Matthias Kroner
Original assignee: Basf Aktiengesellschaft
Priority date: 1994-08-04
Filing date: 1995-07-21
Publication date: 1996-02-15
Also published as: DE4427630A1

Abstract

A process is disclosed for preparing polymers with hydroxamic acid, hydroxamic acid ether and/or hydrazide groups in the side chain, by reacting (a) polymers which contain ester, amide, imide and/or acetal groups in the main chain and carboxyl, ester, imide, amide and/or anhydride groups and/or halogen as side chain, or a polysuccinimide with (b) hydroxylamine, hydroxylamine alkyl ethers with 1 to 18 C atoms in the alkyl group, N-monoalkylhydroxylamines with 1 to 18 C atoms in the alkyl group and/or in salts of said compounds and/or (c) hydrazine and/or hydrazine salts in an aqueous medium or alcohols at pH values of at least 7. Also disclosed is the use of the thus obtained modified polymers as additives to washing and cleaning agents, as complexing agents for alkaline earth and heavy metal ions, as pigment dispersants and as scale inhibitors.

Description

Process for the preparation of polymers containing hydroxamic acid, hydroxamic acid ether and / or hydrazide groups in the side chain and their use

description

The invention relates to a process for the preparation of polymers which contain hydroxamic acid, hydroxamic acid ether and / or hydrazide groups in the side chain, by polymer-analogous reaction with hydroxylamine, hydroxylamine-O-alkyl ethers and / or hydrazine and the use of the polymers as Additive to detergents and cleaning agents, as a complexing agent, dispersant and as a scale inhibitor.

From WO-A-94/011486 modified polyaspartic acids are known which can be obtained by polycondensation of aspartic acid with fatty acids, polybasic carboxylic acids, alcohols, amines or, for example, with hydroxylamine or with hydrazine. The modified polyaspartic acids are used as additives to low-phosphate and phosphate-free detergents and cleaning agents, as water treatment agents and as deposit inhibitors in the evaporation of sugar juice. In the polycondensation, hydroxylamine and hydrazine have a chain-terminating effect, so that the degrees of polycondensation of the modified polyaspartic acids obtainable in this way are limited.

From J. Polymer Science, Part. A, Polym. Former, Volume 26, 2623 (1988) it is known that polyacrylamides can be converted into polyhydroxy acids by reaction with hydroxylamine.

The object of the present invention is to provide a process for the preparation of polymers which contain hydroxamic acids in the side chain and which are biodegradable if possible.

The object is achieved according to the invention with a process for the preparation of polymers which contain hydroxamic acid, hydroxamic acid ether and / or hydrazide groups in the side chain, if one

(a) Polymers which contain ester, amide, imide and / or acetal groups in the polymer main chain and carboxyl, ester imide, amide and / or anhydride groups and / or halogen as the side chain, or contain polysuccinimide 2

(b) hydroxylamine, hydroxylamine-O-alkyl ethers with 1 to

18 carbon atoms in the alkyl group, N-monoalkylhydroxylamines with 1 to 18 carbon atoms in the alkyl group and / or the salts of the compounds mentioned and / or

(c) hydrazine and / or salts of hydrazine

reacted in aqueous medium or in alcohols at pH values of at least 7.

The polymers containing hydroxamic acid, hydroxamic acid ether and / or hydrazide groups obtainable in this way are used as additives for detergents and cleaning agents, as complexing agents for alkaline earth and heavy metal ions, as dispersants for pigments and as scale inhibitors.

The polymers that are suitable as component (a) should preferably be biodegradable. Such polymers are, for example, polyester carboxylates, they contain repeating ester groups in the main polymer chain and carboxyl or carboxylate groups in the side chain. Such polyester carboxylates are produced, for example, by polycondensing dihydric or polyhydric alcohols with a carboxylic acid having at least three carboxyl groups or an ester of such a carboxylic acid. Further suitable polyester carboxylates are poly (malic acid), poly (malic acid) methyl ester, poly (malic acid) ethyl ester, poly tartaric acid dimethyl ester, polycitric acid and polyester, which according to the teaching of EP-A-0 484 606 by condensation of tartaric acid, tartaric anhydride alone or by condensation and mixtures of tartaric anhydride or tartaric acid anhydride or are available in a molar ratio of 1: 0.1 to 1: 4. In the production of these polyesters, the condensation can optionally be carried out additionally in the presence of up to 60 mol% of malic acid. Also suitable as polymers (a) are the polyester carboxylates known from WO-A-93/13192, which by condensation of

(1) Butane-l, 2,3,4-tetracarboxylic acid, which can be replaced by up to 70 mol% with mono- or dibasic hydroxycarboxylic acids or up to 49 mol% with other two- to four-basic aliphatic carboxylic acids (2 ⁾ polyhydroxy compounds from the group of the mono-, oligo- and polysaccharides of the reduced mono- or oligosaccharides and their amino derivatives, the oxidized mono-, oligo- or polysaccharides, alkyl polyglycosides, polyvinyl alcohols, oligoglycerols with more than two glycerol units or their mixtures and optionally

(3) up to 20 mol%, based on component (1), of C ₂ - to C ₄ -alkylene glycols, polyalkylene glycols with a molecular weight of up to 2000 or monovalent C ₄ - to C o, optionally with up to 50 mol of alkylene oxide alkylated -Alcohols

in a weight ratio (1): (2) of 50: 1 to 0.05: 1 can be produced and a K value of 8 to 200 (determined according to H. Fikentscher in 2% by weight aqueous solution at 25 ° C. and pH 7 at the Na salt of the condensation products).

Another suitable group of polymers (a) are polyacetal carboxylates. Such compounds are known for example from EP-B-0 001 004. They are made by polymerizing

Glyoxylic acid esters prepared in the presence of initiators. They contain repeating acetal groups in the main chain and ester groups of C ₄ -C ₄ -alcohols, alkanolamine groups, free carboxyl groups or carboxylate groups which can be obtained by neutralization with alkali metal bases or ammonium bases. These polyacetal carboxylates are biodegradable. further suitable polyacetals are known, for example, from WO-A-92/15629. They are prepared, for example, by polymerizing methyl β-formylpropionate and, if appropriate, hydrolysing the ester groups of the polyacetal carboxylates. Of the polyester carboxylates, polyglyoxylic acid or methyl polyglyoxylate is preferably used as polymer (a).

Another group of polymers (a) are polyamide carboxylates. These polymers contain repeating carbonamide groups in the main chain and free carboxyl groups in the side chain, carboxyl groups neutralized with alkali metal bases or ammonium bases or they are esterified with C 1 -C 4 -alcohols. Examples of polyamide carboxylates are polyglutonic acid, polyglutamic acid benzyl ester, polyglutamic acid methyl ester, polyglutamic acid ethyl ester, polyaspartic acid, polyaspartic acid methyl ester and polyaspartic acid ethyl ester. In the case of the polyester carboxylates, polyamide carboxylates and the polyacetal carboxylates, the pendant carboxyl groups can also be in the form of the amides, imides, nitriles or as anhydride groups or can be replaced by halogen.

Polysuccinimide is also suitable as polymer (a). It can be prepared, for example, by solid-phase polycondensation of powdered aspartic acid at 200 to 250 ° C or by polymerizing aspartic acid in the presence of phosphoric acid or phosphorous acid at 140 to 250 ° C. Poly succinimide is also formed by polycondensation of adducts from maleic acid, maleic anhydride, fumaric acid or malic acid with ammonia or ammonium salts at 120 to 300 ° C.

The molecular weight of the polymers mentioned under (a) (weight average) is, for example, 500 to 200,000, preferably 500 to 20,000.

The compound of component (b) is hydroxylamine or the above-mentioned hydroxyl derivative. Because of the ease of handling, hydroxylamine is preferably used in the form of the salts, for example as hydrochloride or as hydroxylammonium sulfate or as a solution in an organic solvent such as methanol or ethanol. Also suitable as compounds of component (b) are hydroxylamine O-alkyl ethers having 1 to 18 carbon atoms in the alkyl group. From this group of compounds, the hydroxylamine methyl ether and hydroxylaminethyl ether are preferably used. Also suitable as compounds of group (b) are N-monoalkylhydroxylamines having 1 to 18 carbon atoms in the alkyl group. The hydroxylamine alkyl ethers and the N-monoalkyl-substituted hydroxylamines can also be used in the form of the salts, for example as chloride, phosphate or sulfate.

The group (c) compound which can be used is hydrazine which, like the compounds of group (b) - can be used in the form of the salts, e.g. Hydrazine sulfate or hydrine hydrochloride.

The reaction of the polymers (a) with the compounds (b) and / or (c) takes place, for example, in an aqueous medium or in alcohols at pH values of at least 7. Suitable alcohols are soluble in water, such as methanol, ethanol, isopropanol, n- Butanol, ethylene glycol, propylene glycol and glycerin. Suitable solvents are also polyalkylene glycols such as polyethylene glycol, polypropylene glycol, polytetrahydrofuran and alkoxylated Ci to Ciβ alcohols, which can contain, for example, 1 to 100 ethylene oxide units per mole of alcohol. Under aqueous medium, the lying connection be understood as water as the sole solvent as well as in a mixture with a water-soluble alcohol, polyalkylene glycol and / or an alkoxylated alcohol.

For example, 0.001 to 1, preferably 0.1 to 1.0 mol of the compounds (b) and / or (c) are used per mole of the functional groups in the side chain of the polymers (a). The reaction of the polymers (a) with the compounds (b) and / or (c) is preferably carried out at pH values from 7.5 to 12 and mostly in the pH range from 8.0 to 11.0. The pH of the reaction mixture is adjusted by adding bases to the reaction mixture and is advantageously checked during the reaction period. All alkali metal bases can be used as bases for adjusting the pH, preferably sodium hydroxide solution and potassium hydroxide solution, alkaline earth metal bases such as calcium hydroxide or barium hydroxide, and ammonia and amines. Sodium hydroxide solution or potassium hydroxide solution is preferably used as the base.

The reaction times depend on the pH of the reaction medium and the temperature. The temperatures at which the reaction is carried out are usually 0 to 100 ° C, but can also be outside this range. The reaction is preferably carried out at temperatures of 20 to 90 ° C. The response times are e.g. between one minute and 60 hours, usually 30 minutes to 50 hours. In order to carry out the reaction, components (b) and / or (c) can, for example, be introduced in an aqueous medium or in an alcohol and the polymers (a) added in portions, continuously or all at once. However, the procedure can also be such that the polymers (a) are initially introduced into a solution, the solids content of these solutions being, for example, 5 to 80% by weight, and for this the components (b) and / or (c) depending on Reactivity added in portions, continuously or all at once and allowed to react. However, one can also proceed in such a way that components (a), (b) and / or (c) are simultaneously introduced into a reaction zone and allowed to react. The method can be carried out continuously or batchwise.

The polymers (a) used are preferably polyester carboxylates, polyglyoxylic esters, polyglyoxylic acid, alkali or ammonium salts of polyglyoxylic acid, polysuccinimides, polyaspartic acid and the sodium or ammonium salts of polyaspartic acid and / or polyamide carboxylates. In the process according to the invention, for example, polyaspartic acids containing hydroxamic acid groups are prepared by: (a) polysuccinimide, polyaspartic acid and / or water-soluble alkali metal, ammonium or alkaline earth metal salts of polyaspartic acid with

(b) hydroxylamine or hydroxylammonium salts

converts to pendant hydroxam-containing polymers. The aspartic acid in the polysuccinimides can be linked in an α- or β-like manner. The proportions of both forms can be different. The proportion of both forms in the polysuccinimide can be, for example, 10 to 90 mol%. Polyaspartic acid, polyglutamic acid, polyglyoxylic acid, poly malic acid, poly tartaric acid or polycitric acid containing hydroxamic acid groups are biodegradable.

The polymers containing hydroxamic acid, hydroxamic acid ether and / or hydrazide groups obtainable by the process according to the invention are used, for example, as an additive to phosphate-reduced or phosphate-free washing and cleaning agents. Phosphate-reduced detergents and cleaning agents are to be understood as meaning those formulations which contain less than 25% by weight of phosphate, calculated as trisodium polyphosphate. The compounds to be used according to the invention are used in amounts of 0.1 to 30, preferably 1.0 to 10% by weight in detergents and cleaning agents. They act as a bleach activator if the detergents and cleaning agents contain a perborate, for example. The high incrustation-inhibiting effect of polyaspartic acids containing hydroxamic acid groups is particularly remarkable.

The polymers obtainable by the process according to the invention which contain hydroxamic acid, hydroxamic acid ether and / or hydrazide groups in the side chain have, for example, molecular weights from 150 to 200,000, preferably from 300 to 50,000 (weight average).

The products produced according to the invention are also suitable as complexing agents for alkaline earth and heavy metal ions and as dispersants for pigments. Dispersants are used, for example, in amounts of 0.01 to 2% by weight, based on the pigments. Another area of application of the polymers prepared according to the invention is as a scale inhibitor.

Scaleinhihibtoren are usually used in amounts of 1 to 100 ppm, based on the aqueous system. The polymers described are of particular importance for seawater desalination in the latter application. They can also be used as deposit inhibitors for the evaporation of sugar juices.

The K values of the polymers were determined according to H. Fikentscher, Cellulose-Chemie, Vol. 13, 58 to 64 and 71 to 74 (1932) in one percent solution in dimethylformamide (unless another solvent is specified) at a temperature of 25 ° C. certainly. The molecular weight Mw was determined on the sodium form of the polymers with the aid of gel permeation chromatography, polyacrylic acids calibrated using the light scattering method being used as calibration substances. The percentages in the examples mean percent by weight.

Examples

Polycondensate 1

133 g (1 mol) of aspartic acid and 184 g (1.5 mol) of 75% phosphoric acid are mixed in a 1-1-liter glass reactor equipped with an anchor stirrer and at 100 ° C. and under a pressure of 100 mbar drained. This creates a homogeneous solution. The temperature is then raised to 180 ° C. and the polycondensation is continued for 2 hours at this temperature. The reaction mixture is then allowed to cool to 50 ° C. and water is added. The polyaspartimide is crushed, the adhering phosphoric acid is washed out with water and dried in a drying cabinet at 60 ° C. It has a K value of 21.3 and a molecular weight Mw of 5,000.

example 1

To a slurry of 19.4 g (0.2 mol) of polycondensate 1 in 130 g of water, 76.2 g of a 6.5% ethanolic hydroxylamine solution and. Are added at a temperature of 10 ° C. within 30 minutes under pH control at the same time a total of 7.2 g of a 50% aqueous sodium hydroxide solution so that the pH of the reaction mixture is kept at 10. The reaction mixture is then stirred at 20 ° C. for 2 days. Then insoluble matter is filtered off and the filtrate is subjected to freeze drying. This gives 24.6 g of the sodium salt

Polyaspartic acid containing hydroxamic acid groups with a residual water content of 5.3%. The molecular weight of the polymer in the salt form is 1,600.

Claims

claims

1. A process for the preparation of polymers which contain hydroxamic acid, hydroxamic acid and / or hydrazide groups in the side chain, characterized in that

(a) Polymers which contain ester, amide, imide and / or acetal groups in the polymer main chain and contain carboxyl, ester, imide, amide and / or anhydride groups and / or halogen as side chain, or polysuccinimide

(b) hydroxylamine, hydroxylamine-O-alkyl ethers with 1 to

(c) hydrazine and / or salts of hydrazine

reacted in aqueous medium or in alcohols at pH values of at least 7.

2. The method according to claim 1, characterized in that 0.001 to 1 mol of the compounds (b) and / or (c) is used per mole of the functional groups in the side chain of the polymers (a).

3. The method according to claim 1 or 2, characterized in that one carries out the reaction at pH values from 7.5 to 12.

4. The method according to any one of claims 1 to 3, characterized gekenn¬ characterized in that the polymers (a) polyester carboxylates, polyglyoxylic acid esters, polyglyoxylic acid, alkali metal or ammonium salts of polyglyoxylic acid, polysuccinimides and / or polyamide carboxylates.

5. The method according to any one of claims 1 to 4, characterized gekenn¬ characterized in that one

(a) polysuccinimide, polyaspartic acid and / or their water-soluble alkali, ammonium or alkaline earth metal salts

(b) hydroxylamine or hydroxylammonium salts

converted to pendant hydroxam group-containing polymers.

6. Use of the polymers containing hydroxamic acid, hydroxamic acid ether and / or hydrazide groups obtainable according to claims 1 to 5 as an additive to detergents and cleaners, as complexing agents for alkaline earth and heavy metal ions, as dispersants for pigments and as scale agents inhibitor.

Summary

Process for the preparation of polymers which contain hydroxamic acid, hydroxamic acid ether and / or hydrazide groups in the side chain by reacting

(a) Polymers which contain ester, amide, imide and / or acetal groups in the polymer main chain and carboxyl, ester, imide, amide and / or anhydride groups and / or halogen as side chain, or contain polysuccinimide

(b) hydroxylamine, hydroxylamine alkyl ethers having 1 to 18 carbon atoms in the alkyl group, N-monoalkylhydroxylamines having 1 to

18 carbon atoms in the alkyl group and / or in salts of the compounds mentioned and / or

(c) hydrazine and / or salts of hydrazine

in an aqueous medium or in alcohols at pH 7 and use of the modified polymers obtainable in this way as an additive to detergents and cleaning agents, as a complexing agent for alkaline earth and heavy metal ions, as a dispersant for pigments and as a scale inhibitor.