Use of branched polyesters based on citric acid as additive in washing compositions, detergents or a formulation for water treatment

Abstract

The present invention relates to the use of branched polyesters obtainable by polycondensation of citric acid with at least one polyalcohol, and optionally with polycarboxylic acid component as additive in washing compositions, cleaners, detergents or a formulation for water treatment and to mixtures comprising such branched polyesters. The invention further relates to the use of hydrophobically modified branched polyesters, and to the method for cleaning, washing or water treatment using such branched polyesters.

Claims

1. An additive comprising a branched polyester obtained by polycondensation monomers consisting of a. citric acid as component A with b. at least one polyalcohol as component B and c. optionally an aliphatic dicarboxylic acid component as component C and reaction with d. at least one component D selected from the group consisting of C6-C30 alkyl- or alkenylcarboxylic acids, C6-C30 alkyl or alkenyl alcohols, C6-C30 alkyl- or alkenylamines, and C6-C30 aliphatic isocyanates, during the polycondensation or subsequently, wherein the additive is used in a washing composition, a cleaner, a detergent or a formulation for water treatment, wherein the branched polyester has a molecular weight M.sub.n of from 400 to 5,000 g/mol; and wherein the polycondensation does not utilize an enzyme; wherein the molar ratio of (component A+component B) to component D is 10:0.1 to 0.5:0.1.

2. The additive according to claim 1, wherein the additive is a scale inhibitor in a water-conveying system.

3. The additive according to claim 1, wherein the molar ratio of citric acid to polyalcohol is 5.0:1.0 to 1.0:1.5.

4. The additive according to claim 1, wherein component B is ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol, polyethylene glycol with an average molecular weight between 200 and 1000 g/mol, glycerol, diglycerol, triglycerol, trimethylolpropane, trimethylolethane, di(trimethylolpropane), 1,2,4-butanetriol, 1,2,6-hexanetriol, pentaerythritol, sucrose, sorbitol, glucaric acid, or polyetherols thereof based on ethylene oxide and/or propylene oxide, or a mixture thereof.

5. The additive according to claim 1, wherein component B is diethylene glycol with an average molecular weight between 200 and 1000 g/mol, polyethylene glycol with an average molecular weight between 200 and 1000 g/mol, trimethylolpropane, glycerol, diglycerol, triglycerol, or polyetherols thereof based on ethylene oxide or propylene oxide, or a mixture thereof.

6. The additive according to claim 1, wherein component C is malonic acid, succinic acid, glutaric acid, adipic acid, sebacic acid, octadecenylsuccinic anhydride, a 1,2-cyclohexanedicarboxylic acid, a 1,3-cyclohexanedicarboxylic acid, a 1,4-cyclohexanedicarboxylic acid, cis-hexahydrophthalic acid, trans-hexahydrophthalic acid, a mixture of cis-hexahydrophthalic acid and trans-hexahydrophthalic acid, phthalic acid, isophthalic acid, terephthalic acid, anhydrides, monoalkyl esters or dialkyl esters.

7. The additive according to claim 1, wherein component D is oleic acid, palmitic acid, linoleic acid, stearic acid, lauric acid or ricinoleic acid.

8. The additive according to claim 1, wherein the washing composition is a dishwashing composition.

9. A process for preparing the hydrophobically modified branched polyesters of the additive according to claim 1, comprising polycondensing monomers consisting of a) citric acid as component A, b) at least one polyalcohol as component B, and c) optionally an aliphatic dicarboxylic acid component as component C to give branched polyesters, and reacting a component D during or subsequent to the polycondensation, wherein component D is selected from the group consisting of C6-C30 alkyl- or alkenylcarboxylic acids, C6-C30 alkyl or alkenyl alcohols, C6-C30 alkyl- or alkenylamines, and C6-C30 aliphatic isocyanates; and wherein the polycondensation does not utilize an enzyme; wherein the molar ratio of (component A+component B) to component D is 10:0.1 to 0.5:0.1.

10. A hydrophobically modified branched polyester prepared according to the process according to claim 9.

11. The additive according to claim 1, wherein component C is selected from the group consisting of oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azaleic acid, sebacic acid, undecane-,-dicarboxylic acid, dodecane-,-dicarboxylic acid, cis- and trans-cyclohexane-1,2-dicarboxylic acid, cis- and trans-cyclohexane-1,3-dicarboxylic acid, cis- and trans-cyclohexane-1,4-dicarboxylic acid, cis- and trans-cyclopentane-1,2-dicarboxylic acid, cis- and trans-cyclopentane-1,3-dicarboxylic acid and combinations thereof, optionally substituted by one or more radicals selected from the group consisting of C.sub.1-C.sub.20-alkyl groups, C.sub.2-C.sub.20-alkenyl groups, C.sub.3-C.sub.12-cycloalkyl groups, alkylene groups, or C.sub.6-C.sub.14-aryl groups.

Description

EXAMPLES

Preparation of the Polyesters According to the Invention

(1) General Remarks:

(2) The molecular weights were determined by gel permeation chromatography (GPC) (eluent: THF; standard: PMMA; detector: refractive index detector).

(3) The acid numbers (mg KOH/g of polymer) were determined in accordance with DIN 53402.

(4) TMP is understood as meaning trimethylolpropane.

(5) TMPn EO is understood as meaning trimethylolpropane alkoxylated with n mol of ethylene oxide, where n can be an average value (number-average).

(6) PEG 200 is understood as meaning a polyethylene glycol with an average molecular weight of 200 g/mol.

(7) Polyglycerol 3 is understood as meaning triglycerol.

(8) Polymer 1: Polycondensate of Citric Acid Monohydrate/TMP 1.5:1.0

(9) A 500 ml round-bottomed flask equipped with stirrer, internal thermometer, gas inlet tube and descending condenser with collecting vessel was charged with 210.4 g (1.00 mol) of citric acid monohydrate and 89.6 g (0.67 mol) of TMP, and 0.1 g (400 ppm) of titanium(IV) tetrabutoxide. Under nitrogen gassing, the mixture was heated to 130 C. and held at this temperature for 2 h with stirring, during which water of reaction and water of crystallization that was liberated was separated off via the descending condenser. The reaction was then ended by cooling to room temperature. The product was obtained in the form of a yellow water-soluble resin.

(10) The following characteristic data were determined:

(11) Acid number=345 mg KOH/g of polymer

(12) M.sub.n=570 g/mol, M.sub.w=2580 g/mol

(13) Polymer 2: Polycondensate of Citric Acid Monohydrate/TMP 2.0:1.0

(14) A 500 ml round-bottomed flask equipped with stirrer, internal thermometer, gas inlet tube and descending condenser with collecting vessel was charged with 151.6 g (0.77 mol) of citric acid monohydrate and 48.8 g (0.37 mol) of TMP, and 0.06 g (300 ppm) of titanium(IV) tetrabutoxide. Under nitrogen gassing, the mixture was heated to 130 C. and held at this temperature for 2 h with stirring, during which water of reaction and water of crystallization that was liberated was separated off via the descending condenser. The reaction was then ended by cooling to room temperature. The product was obtained in the form of a yellow water-soluble resin.

(15) The following characteristic data were determined:

(16) Acid number=398 mg KOH/g of polymer

(17) M.sub.n=550 g/mol, M.sub.w=3990 g/mol

(18) Polymer 3: Polycondensate of Citric Acid Monohydrate/TMP/TMP12.2 EO 1.7:0.5:0.5

(19) A 500 ml round-bottomed flask equipped with stirrer, internal thermometer, gas inlet tube and descending condenser with collecting vessel was charged with 141.1 g (0.67 mol) of citric acid monohydrate, 132.4 g (0.20 mol) of TMP12 EO and 26.5 g (0.20 mol) of TMP, and 0.1 g (400 ppm) of titanium(IV) tetrabutoxide. Under nitrogen gassing, the mixture was heated to 130 C. and held at this temperature for 2.5 h with stirring, during which water of reaction and water of crystallization that was liberated was separated off via the descending condenser. The reaction was then ended by cooling to room temperature.

(20) The product was obtained in the form of a yellow water-soluble resin.

(21) The following characteristic data were determined:

(22) Acid number=262 mg of KOH/g of polymer

(23) M.sub.n=1170 g/mol, M.sub.w=2260 g/mol

(24) Polymer 4: Polycondensate of citric acid monohydrate/polyglycerol 3-3.0:1.0

(25) A 500 ml round-bottomed flask equipped with stirrer, internal thermometer, gas inlet tube and descending condenser with collecting vessel was charged with 217.4 g (1.03 mol) of citric acid monohydrate and 82.4 g (0.34 mol) of polyglycerol 3, and 0.015 g (50 ppm) of sulfuric acid. Under nitrogen gassing, the mixture was heated to 130 C. and held at this temperature for 4 h with stirring, during which water of reaction and water of crystallization that was liberated was separated off via the descending condenser. The reaction was then ended by cooling to room temperature.

(26) The product was obtained in the form of a yellow water-soluble resin.

(27) The following characteristic data were determined:

(28) Acid number=428 mg of KOH/g of polymer

(29) M.sub.n=1320 g/mol, M.sub.w=1600 g/mol

(30) Polymer 5: Polycondensate of Citric Acid Monohydrate/Polyglycerol 3/TMP 4.0:1.0:1.0

(31) A 500 ml round-bottomed flask equipped with stirrer, internal thermometer, gas inlet tube and descending condenser with collecting vessel was charged with 207.5 g (1.00 mol) of citric acid monohydrate, 59.3 g (0.25 mol) of polyglycerol 3 and 33.1 (0.25 mol) of TMP, and 0.1 g (400 ppm) of titanium(IV) tetrabutoxide. Under nitrogen gassing, the mixture was heated to 130 C. and held at this temperature for 3.5 h with stirring, during which water of reaction and water of crystallization that was liberated was separated off via the descending condenser. The reaction was then ended by cooling to room temperature.

(32) The product was obtained in the form of a yellow water-soluble resin.

(33) The following characteristic data were determined:

(34) Acid number=378 mg of KOH/g of polymer

(35) M.sub.n=520 g/mol, M.sub.w=700 g/mol

(36) Polymer 6: Polycondensate of Citric Acid Monohydrate/Diethylene Glycol/TMP 1.7:0.5:0.5 (Without Cat.)

(37) A 500 ml round-bottomed flask equipped with stirrer, internal thermometer, gas inlet tube and descending condenser with collecting vessel was charged with 224.5 g (1.07 mol) of citric acid monohydrate, 33.3 g (0.31 mol) of diethylene glycol and 42.2 g (0.31 mol) of TMP. Under nitrogen gassing, the mixture was heated to 130 C. and held at this temperature for 2.0 h with stirring, during which water of reaction and water of crystallization that was liberated was separated off via the descending condenser. The reaction was then ended by cooling to room temperature.

(38) The product was obtained in the form of a dark yellow water-soluble resin. The following characteristic data were determined:

(39) Acid number=412 mg of KOH/g of polymer

(40) M.sub.n=1300 g/mol, M.sub.w=3500 g/mol

(41) Polymer 7: Polycondensate of Citric Acid Monohydrate/TMP/PEG 200 1.7:0.5:0.5 (Without Cat.)

(42) A 1000 ml round-bottomed flask equipped with stirrer, internal thermometer, gas inlet tube and descending condenser with collecting vessel was charged with 204.4 g (0.97 mol) of citric acid monohydrate, 57.2 g (0.29 mol) of PEG 200 and 38.4 g (0.29 mol) of TMP. Under nitrogen gassing, the mixture was heated to 130 C. and held at this temperature for 8 h with stirring, during which water of reaction and water of crystallization that was liberated was separated off via the descending condenser. The reaction was then ended by cooling to room temperature.

(43) The product was obtained in the form of a yellow water-soluble resin.

(44) The following characteristic data were determined:

(45) Acid number=347 mg of KOH/g of polymer

(46) M.sub.n=890 g/mol, M.sub.w=2700 g/mol

(47) Polymer 8: Polycondensate of Citric Acid Monohydrate/TMP/Oleic Acid 1.5:1.0:0.2 (Without Cat.)

(48) A 1000 ml round-bottomed flask equipped with stirrer, internal thermometer, gas inlet tube and descending condenser with collecting vessel was charged with 186.9 g (0.88 mol) of citric acid monohydrate, 79.6 g (0.593 mol) of trimethylolpropane and 33.5 g of oleic acid (0.119 mol). Under nitrogen gassing, the mixture was heated to 130 C. and held at this temperature for 2 h with stirring, during which water of reaction and water of crystallization that was liberated was separated off via the descending condenser. The reaction was then ended by cooling to room temperature.

(49) The product was obtained in the form of a yellow water-soluble resin.

(50) The following characteristic data were determined:

(51) Acid number=321 mg of KOH/g of polymer

(52) M.sub.n=1400 g/mol, M.sub.w=2800 g/mol

(53) Polymer 9: Polycondensate of Citric Acid Monohydrate/TMP/Oleic Acid 1.5:0.5:0.1 (without cat.)

(54) A 1000 ml round-bottomed flask equipped with stirrer, internal thermometer, gas inlet tube and descending condenser with collecting vessel was charged with 186.9 g (0.88 mol) of citric acid monohydrate, 79.6 g (0.593 mol) of trimethylolpropane and 16.75 g of oleic acid (0.06 mol). Under nitrogen gassing, the mixture was heated to 130 C. and held at this temperature for 2 h with stirring, during which water of reaction and water of crystallization that was liberated was separated off via the descending condenser. The reaction was then ended by cooling to room temperature.

(55) The product was obtained in the form of a yellow water-soluble resin.

(56) The following characteristic data were determined:

(57) Acid number=314 mg of KOH/g of polymer

(58) M.sub.n=1700 g/mol, M.sub.w=3000 g/mol

(59) Calcium Carbonate Inhibition Test

(60) A solution of NaHCO.sub.3, Mg.sub.2SO.sub.4, CaCl.sub.2 and polymer is shaken in a waterbath for 2 h at 70 C. After filtering the still-warm solution through a 0.45 m Milex filter, the Ca content of the filtrate is ascertained by complexometry or by means of a Ca.sup.2+-selective electrode, and the CaCO.sub.3 inhibition is ascertained in % by means of a before/after comparison (see formula I).

(61) TABLE-US-00001 Ca.sup.2+ 215 mg/L Mg.sup.2+ 43 mg/L HCO.sub.3.sup. 1220 mg/L Na.sup.+ 460 mg/L Cl.sup. 380 mg/L SO.sub.4.sup.2 170 mg/L Polymer 5 mg/L Temperature 70 C. Time 2 hours pH 8.0-8.5

(62) ${\mathrm{CaCO}}_3\mathrm{inhibition}\left(\%\right)=\frac{\begin{array}{c}\mathrm{mg}\mathrm{of}\left(\mathrm{Ca}2+\right)\mathrm{after}24h-\\ \mathrm{mg}\mathrm{of}\left(\mathrm{Ca}2+\right)\mathrm{blank}\mathrm{value}\mathrm{after}24h\end{array}}{\begin{array}{c}\mathrm{mg}\mathrm{of}\left(\mathrm{Ca}2+\right)\mathrm{zero}\mathrm{value}-\\ \mathrm{mg}\mathrm{of}\left(\mathrm{Ca}2+\right)\mathrm{blank}\mathrm{value}\mathrm{after}24h\end{array}}*100$

(63) TABLE-US-00002 TABLE 1 Example Inhibition [%] 1 40.9 2 48.5 3 55.4 4 32.1 5 36.7 6 28.2 7 34.1 8 44.1 9 30.5

(64) The polymers were tested in the following phosphate-free formulations PF1 and PF2, and also in the phosphate-based formulation P1.

(65) TABLE-US-00003 TABLE 2 PF 1 PF 2 P1 Protease 2.5 2.5 1 Amylase 1.0 1.0 0.2 Nonionic surfactant 5.0 5 3 Polymer 10 10 6.5 Sodium percarbonate 10.5 10.5 14 Tetraacetylethylenediamine 4 4 4 Sodium disilicate 2 2 2 Sodium tripolyphosphate 50 Sodium carbonate 19.5 19.5 18.8 Sodium citrate dihydrate 35 Methylglycinediacetic acid 10 45 Hydroxyethane-(1,1- 0.5 0.5 0.5 diphosphonic acid)

(66) Data in % by weight based on the total amount of all components

(67) The following experimental conditions were observed:

(68) Dishwasher: Miele G 1222 SCL

(69) Program: 65 C. (with prewash)

(70) Dishes: 3 knives (WMF Tafelmesser Berlin, monobloc)

(71) 3 Amsterdam 0.2 L drinking glasses 3 OCEAN BLAU breakfast plates (MELAMINE) 3 porcelain plates: 19 cm plates with rims flat
Arrangement: Knives in the cutlery drawer, glasses in the upper baskets, plates in the lower basket
Dishwashing detergent: 18 g
Addition of soil: 50 g of ballast soil is added in thawed form with the formulation after the prewash; for composition see below
Rinse temperature: 65 C.
Water hardness: 21 German hardness (Ca/Mg):HCO3 (3:1):1.35
Wash cycles: 6; break in between for 1 h in each case (10 min with door open, 50 min with door closed)
Evaluation: Visually after 6 wash cycles

(72) The evaluation of the dishes was carried out after 6 cycles in a darkened chamber under light behind an aperture diaphragm using a grading scale from 10 (very good) to 1 (very poor). Grades from 1-10 for spotting (very many, intensive spots=1 ranging to no spots=10) and also for filming (1=very severe filming, 10=no filming) were awarded.

(73) Composition of the Ballast Soil:

(74) Starch: 0.5% potato starch, 2.5% gravy

(75) Fat: 10.2% margarine

(76) Protein: 5.1% egg yolk, 5.1% milk

(77) Others: 2.5% tomato ketchup, 2.5% mustard, 0.1% benzoic acid, 71.4% water

(78) Result:

(79) The formulation containing polymer are characterized in particular by their very high film-inhibiting effect towards inorganic and organic deposits on glass, knives, porcelain and plastic components. Furthermore, they increase the cleaning power of the dishwashing detergent and encourage the water to run off from the dishes.

(80) The tables below list the summed grades for film formation and spotting on knives and drinking glasses.

(81) TABLE-US-00004 Phosphate-free formulation PF 1 Glasses Polymer Knives (F + S) (F + S) 2 17 13 3 18 11 5 18 11 8 16 12 without 8 7

(82) TABLE-US-00005 Phosphate-free formulation PF 2 Glasses Polymer Knives (F + S) (F + S) 2 14 12 3 11 10 5 14 11 8 13 13 without 7 8