HIGHLY STABLE AND ALKALINE CLEANING SOLUTIONS AND SOLUBLE SURFACTANT

Abstract

The present invention relates to new alkaline, preferably highly alkaline, cleaning solutions comprising surfactants with improved stability and cleaning performance under such conditions. It further relates to novel surfactants.

Claims

1-15. (canceled)

16. A cleaning solution, comprising: a) one or more surfactant(s) according to Formula (I) ##STR00002## wherein: R.sub.1 is a linear, branched, or cyclic, saturated or unsaturated aliphatic group having from 3 to 7 carbon atoms, or an aryl group having 6 or 7 carbon atoms or an alkylaryl group having 7 carbon atoms; R.sub.2 and R.sub.3 may be identical or different and are bivalent alkyl radicals with two to four carbon atoms; R.sub.4, R.sub.5, and R.sub.6 may all be identical or two of them may be identical or all may be different and are selected from the group consisting of: ethyl group, 1-methylmethane group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, and tert-butyl group; X.sub.1, X.sub.2 and X.sub.3 may all be identical or two of them may be identical or all may be different and are selected from the group consisting of: OH and O.sup.−Y.sup.+, wherein Y.sup.+ is a cation; m is 0 or 1, n is 0, 1, 2 or 3, and wherein n is 1, 2 or 3 if m=0 and if R.sub.1 comprises a tertiary carbon atom attached to the nitrogen atom; b) one or more alkaline compound(s); and c) water.

17. The cleaning composition of claim 16, wherein in the surfactant: R.sub.1 is a linear, branched, or cyclic, saturated or unsaturated aliphatic group having 3 to 6 carbon atoms; R.sub.2 and R.sub.3 are selected from the group consisting of an n-propyl group and an isopropyl group.

18. The cleaning solution of claim 16, wherein the cleaning solution does not comprise a nonionic surfactant or comprises one or more nonionic surfactant as additional component(s) in an amount, in sum of all nonionic surfactants, equal to or below 0.5 wt % of the overall cleaning solution.

19. The cleaning solution of claim 16, wherein the cleaning solution comprises one or more nonionic surfactants as additional component(s) in an amount, in sum of all nonionic surfactants, of 0.001 wt % to 0.2 wt %.

20. The cleaning solution of claim 16, wherein R.sub.4 and/or R.sub.5 and/or R.sub.6 is ethyl or isopropyl.

21. The cleaning solution of claim 16, wherein: R.sub.1=cyclohexyl, m=0 and n is 0 or 1; or R.sub.1=butyl, m=1 and n is 0 or 1; or R.sub.1=2-ethylpentyl, m=1 and n is 0 or 1.

22. The cleaning solution of claim 16, wherein component b) is selected from the group consisting of a metal hydroxide, an alkaline silicate, an alkaline phosphate, an amine, a chelating agent selected from the group consisting of phosphates, carboxylates, phosphonates, and polyphosphates, or a mixture of these compounds.

23. The cleaning solution of claim 16, wherein component b) comprises at least one alkaline compound in an amount such that the total alkalinity of the cleaning solution, expressed as Na.sub.2O content, is 1.5 wt % or higher.

24. The cleaning solution of claim 23, wherein component b) comprises at least one alkaline compound in an amount such that the total alkalinity of the cleaning solution, expressed as Na.sub.2O content, is 5 wt % or higher.

25. The cleaning solution of claim 23, wherein component b) comprises at least one alkaline compound in an amount such that the total alkalinity of the cleaning solution, expressed as Na.sub.2O content, is 10 to 40 wt %.

26. The cleaning solution of claim 25, wherein component b) comprises one or more alkaline compound(s) selected from the group consisting of a strong base having a pKb value at 25° C. and 1 atm of below 1, and an alkaline silicate, or mixtures thereof, wherein the content of all silicates in sum in the overall composition is below 15% by wt.

27. The cleaning solution of claim 26, wherein component b) comprises sodium and/or potassium hydroxide, and a potassium or sodium silicate, or mixtures.

28. The cleaning solution of claim 23, wherein component b) comprises at least one alkaline compound in an amount such that the total alkalinity of the cleaning solution, expressed as Na.sub.2O content, is of from 1.5 to 10 wt %,

29. The cleaning composition of claim 28, wherein component b) comprises one or more alkaline compound(s) selected from the group consisting of a weak base having a pKb value at 25° C. and 1 atm of 1 to 7, an alkaline silicate, a hydrate of an alkaline silicate, organic alkaline materials, or mixtures thereof; and/or wherein component b) comprises one or more strong base having a pKb value at 25° C. and 1 atm below 1, in sum in an amount to produce a total alkalinity of 1.5-10 wt % of the overall composition, expressed as Na.sub.2O; and/or wherein component b) comprises one or more alkaline silicate(s) with the provision that the overall content of all silicates in sum in the overall composition is below or equal to 10% by wt.

30. The cleaning composition of claim 28, wherein component b) comprises sodium and/or potassium carbonate, potassium or sodium silicate, or mixtures thereof.

31. The cleaning solution of claim 16, wherein the content of component a) in sum is 0.01 to 5 wt %, of the overall cleaning composition.

32. A surfactant according to Formula (I) ##STR00003## wherein: R.sub.1 is a linear, branched, or cyclic, saturated or unsaturated aliphatic group having from 3 to 7 carbon atoms, or an aryl group having 6 or 7 carbon atoms or an alkylaryl group having 7 carbon atoms; R.sub.2 and R.sub.3 may be identical or different and are bivalent alkyl radicals with two to four carbon atoms; R.sub.4, R.sub.5, and R.sub.6 may all be identical or two of them may be identical or all may be different and are selected from the group consisting of an ethyl group, 1-methylmethane group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, or tert-butyl group; X.sub.1, X.sub.2 and X.sub.3 may all be identical or two of them may be identical or all may be different and are selected from the group consisting of OH and O.sup.−Y.sup.+, wherein Y.sup.+ is a cation; m is 0 or 1, n is 0, 1, 2 or 3, and wherein: n is 1, 2 or 3 if m=0 and if R.sub.1 comprises a tertiary carbon atom attached to the nitrogen atom; and R.sub.1 is selected from the group consisting of a linear saturated aliphatic group having from 3 to 5 carbon atoms, a linear unsaturated aliphatic group having from 3 to 7, a branched or cyclic, saturated or unsaturated aliphatic group having from 3 to 7, an aryl group having 6 or 7 carbon atoms and an alkylaryl group having 7 carbon atoms, if n=0 and if m=0 or 1.

33. The surfactant of claim 32, wherein: R.sub.1 is a linear, branched, or cyclic, saturated or unsaturated aliphatic group having 3 to 6 carbon atoms; and R.sub.2 and R.sub.3 are selected from the group consisting of: an n-propyl group and an isopropyl group.

34. The surfactant of claim 32, wherein R.sub.4 and/or R.sub.5 and/or R.sub.6 is ethyl or isopropyl.

35. The surfactant of claim 32, wherein: R.sub.1=cyclohexyl, m=0 and n is 0 or 1; or R.sub.1=butyl, m=1 and n is 0 or 1; or R.sub.1=2-ethylpentyl, m=1 and n is 0 or 1.

Description

EXAMPLES

Example 1: Monosodium Cyclohexylamine Dipropionate

[0084] Approximately 700 g of acrylic acid (obtained commercially from Sigma-Aldrich) was reacted with approximately 416 g of cyclohexylamine (obtained commercially from Sigma-Aldrich) for 6 hours under cooling with constant agitation at about 60-80° C. The resulting organic acid was neutralized in parts with aqueous sodium hydroxide over 2 hours under cooling with constant agitation at about 70° C. The neutralization was done to an extent that ensures that the partially neutralized acid is water soluble at room temperature. The reaction was performed in the presence of water such that the final water content was approximately 60 wt. %.

Example 2: Monosodium Butyloxypropylamine Dipropionate

[0085] Approximately 470 g of acrylic acid (obtained commercially from Sigma-Aldrich) was reacted with approximately 390 g of butyloxypropylamine for 6 hours under cooling with constant agitation at about 60-80° C. The resulting organic acid was neutralized with aqueous sodium hydroxide in parts over 2 hours under cooling with constant agitation at about 70° C. The neutralization was done to an extent that ensures that the partially neutralized acid is water soluble at room temperature. The reaction was performed in the presence of water such that the final water content was approximately 50 wt. %.

Example 3: 1.5 Sodium Butyloxypropylaminopropylamine Tripropionate

[0086] Approximately 232 g of acrylic acid (obtained commercially from Sigma-Aldrich) was reacted with approximately 192 g of n-butyloxypropylaminopropylamine for 6 hours under cooling with constant agitation at about 60-80° C. The resulting organic acid was neutralized in parts with aqueous sodium hydroxide over 2 hours under cooling with constant agitation at about 70° C. The neutralization was done to an extent that ensures that the partially neutralized acid is water soluble at room temperature. The reaction was performed in the presence of water such that the final water content was approximately 50 wt. %.

Example 4: Stability Exhibited by Monosodium Cyclohexylamine Dipropionate

[0087] Approximately 4 g of a 40 wt. % monosodium cyclohexylamine dipropionate solution was added to 200 g of 20 wt. % sodium hydroxide (15.5% total alkalinity expressed as Na.sub.2O). This solution was heated to 150° C. and held at that temperature for 2 weeks. The aged sample was neutralized to a pH of 7 with hydrochloric acid and analyzed via liquid chromatography-mass spectorometry (LC-MS), using a Thermo Acclaim Surfactant Plus chromatography column. Mass spectrometric analyses were performed in positive electrospray ionization mode over the mass range of 100-2500 Daltons (Da) with a time of flight (TOF) mass spectrometer.

[0088] The LC chromatograms for aged and un-aged amphoteric surfactant are shown in FIG. 1. The chromatographic peak at retention time 1.18 minutes was the same in both the aged and un-aged samples, and correlated to cyclohexylamine reacted with only one acrylic acid (m/z 172). For both samples, the mass spectra of the peak at retention time 1.7 minutes matched the expected [M+H]+ value of 244 for the structure of the surfactant.

[0089] The relative concentrations of the components to the rest of the peaks show that the surfactant maintained its molecular integrity through the aging process.

Example 5: Stability Exhibited By Monosodium Butyloxypropylamine Dipropionate

[0090] Approximately 4 g of a 40 wt. % monosodium butyloxypropylamine dipropionate solution was added to 200 g of 20 wt. % sodium hydroxide (15.5% total alkalinity expressed as Na.sub.2O). This solution was heated to 150° C. and held at that temperature for 2 weeks. The aged sample was neutralized to a pH of 7 with hydrochloric acid and analyzed via liquid chromatography-mass spectorometry (LC-MS), using a Thermo Acclaim Surfactant Plus chromatography column. Mass spectrometric analyses were performed in positive electrospray ionization mode over the mass range of 100-2500 Daltons (Da) with a time of flight (TOF) mass spectrometer.

[0091] The LC chromatograms for aged and un-aged monosodium butyloxypropylamine dipropionate are shown in FIG. 2. The chromatographic peak at retention time 1.49 minutes was the same in both the aged and un-aged samples, and correlated to etheramine reacted with only one acrylic acid (m/z 204). The largest peak in both samples, at retention time 2.0 minutes matched the expected [M+H]+ for the structure of the expected product.

[0092] The relative concentrations of the components to the rest of the peaks show that the surfactant maintained its molecular integrity through the aging process.

Example 6: Surface Tension Reduction and Critical Micelle Concentration for Monosodium Cyclohexylamine Dipropionate (Ex 1) and Monosodium Butyloxypropylamine Dipropionate (Ex 2)

[0093] Monosodium Cyclohexylamine Dipropionate (Example 1) and Monosodium Butyloxypropylamine Dipropionate (Example 2) were examined to determine CMC in water and in 20% and 45% potassium hydroxide (KOH). These values and the equilibrium surface tensions (EST) at CMC are shown below in Table 1.

TABLE-US-00001 TABLE 1 Surface Tension Reduction and Critical Micelle Concentration for Example Surfactants CMC (Wt %) EST (mN/m) 20% 45% 20% 45% Material Water KOH KOH Water KOH KOH Monosodium 9.0 0.05 0.03 39.7 40.8 40.9 Cyclohexylamine Dipropionate (Example 1) Monosodium 9.0 0.07 0.03 33.4 36.6 37.5 Butyloxypropylamine Dipropionate (Example 2)

[0094] These values show that the claimed materials meet the definition of surfactants in that they will reduce surface tension and exhibit a critical micelle concentration.

Example 7: Foam Behavior for Example Surfactants

[0095] The foaming properties of solutions of Monosodium Cyclohexylamine Dipropionate (Example 1), Monosodium Butyloxypropylamine Dipropionate (Example 2), and 1.5 Sodium Butyloxypropylaminopropylamine Tripropionate (Example 3), prepared as 2 wt % in 45% KOH, were examined. Samples of each solution were shaken vigorously in an automated apparatus to ensure identical treatment of each sample and the volume of foam relative to the total volume of solution and foam was determined. Results of this examination are shown below in Table 2.

TABLE-US-00002 TABLE 2 Foaming Properties of Example Surfactants. Foam Volume (as Percentage of Solution and Foam Volume) Material Initial 1 Minute 3 Minutes Monosodium Cyclohexylamine 25.6 12.3 0.0 Dipropionate (Example 1) Monosodium Butyloxypropylamine 53.3 48.1 32.1 Dipropionate (Example 2) 1.5 Sodium 57.6 57.5 53.1 Butyloxypropylaminopropylamine Tripropionate (Example 3)

[0096] It may be seen from this data that the claimed surfactants are capable of making both high and low foaming solutions.

Example 8: Dynamic Surface Tension of Monosodium Cyclohexylamine Dipropionate (Ex 1) and Monosodium Butyloxypropylamine Dipropionate (Ex 2)

[0097] Solutions of Monosodium Cyclohexylamine Dipropionate (Example 1) and Monosodium Butyloxypropylamine Dipropionate (Example 2) were prepared at concentrations of 0.01 wt % and 0.005 wt % in 45% KOH. A bubble tensiometer was employed to demonstrate the migration speed of these surfactants in the alkaline solution, revealed by the lowering of the solutions surface tension as a function of surface age. Results of this testing are shown below in FIG. 3.