US2567159A - Wetting and detergent composition - Google Patents

Description

Patented Ifi 4, l95l WE'KTKNG AND DETERGENT CUIWIPOSII'E'ION Emil ll. Vitalis, Springdale, 0011111., assignor to American tlyanarnid (Jompany, New York, N. Y a corporation oi Maine No Brag. Application November 4, 1949, Serial No. 125,661

2 Clo.

This invention relates to wetting and detergent compositions containing monoalkyl suliosuccinates together with solubillzing agents therefor. The invention includes the compositions themselves, their methods of preparation, and wetting and detergent processes in which these compositions are used.

It is known that the higher monoalkyl sulfosuccinates, when used in the form of their salts with monovalent salt-forming compounds, possess good Wetting and particularly good detergent properties. However, the salts of monoesters of suliosuccinic acid with alcohols of 12 or more carbon atoms, which is the minimum chain length for good detergency, possess relatively low solubility in water, which is a serious disadvantage. It is a principal object of the present invention to provide for this class of compounds solubilizing agents which improve their water solubility and thus increase their usefulness as wetting agents and detergents. A further object resides in the provision of readily soluble pastes or powders containin the higher monoalkyl sulfosuccinates in a solubilized and therefore Water-dispersible condition. Still further objects of the invention will be apparent from the following detailed description of preferred embodiments thereof.

As is noted above the sodium, potassium, ammonium, ethanolamine and similar salts of the higher monoalkyl sulfosuccinates in which the alkyl radical contains 12 or more carbon atoms are only slightly soluble in water. The solubility of the disodium salts, which is given in the following table, is typical of the corresponding salts of potassium and ammonium as well.

Solubility,

Monoalkyl Disodium Sulfosuccinate gins [100 cc.

of Solution DodecyL 4. 5 TctradecyL 0. 05 Hcxadecyl- 0. 2 Octadecyl 0. 05

carbon nature boiling at 39 C. to 96 C. at 0.3 mm. of mercury pressure and therefore containing about 14-16 carbon atoms, and about 58% of higher boiling materials, possibly higher alcohols. This mixture is hereinafter designated as Ammeco which is its commercial name.

Attempts have been made to solubilize these and similar compounds by addin water-soluble alcohols, ethers of ethylene glycol and other agents which are known to solubilize the higher dialkyl sulfosuccinates. However, it was found that these alcohols and ethers actually reduce the water solubility of the alkali metal and ammonium salts of higher monoallryl sulfosuccinates.

I have now discovered that water-soluble chromium salts such as chromium sulfate, chromium chloride, chromium nitrate, and the like are excellent solubilizing agents for the higher monoalkyl sulfosuccinate salts. This is a remarkable discovery, for the addition of the corresponding salts of alkali metals such as sodium or potassium sulfate or chloride causes precipitation of the higher monoalkyl sulfosuccinate salts instead of solubilizing them. I have found, however, that I can prepare stable aqueous solutions containing from about 1% to about 30% of the wetting agents, depending on the particular alcohol present in the sulfosuccinate ester, as well as water-soluble concentrated aqueous pastes containin about 30-70% of the wetting agents, and even water-soluble dry powders containing the higher monoalkyl sulfosuccinate salts together with inorganic salts of the type of sodium sulfate, sodium chloride and the like by incorporating therein suitable quantities of chromium salts which ionize in aqueous solution.

The monoalkyl sulfosuccinate salts which are solubilized by chromium salts in accordance with the present invention have the following formula MOaS.C.COOM

-JJOOR H2 in which M is a monovalent salt-forming group such as sodium, potassium, ammonium, ethanolamine and'the like, and R is an alkyl radical, of at least 12 carbon atoms and preferably 12 to 18 carbon atoms which may be saturated or unsaturated, or a mixture of such alkyl radicals. The compounds defined by the above formula are preferably prepared by esteriiying maleic anhydride or maleic acid with dodecyl, tetradecyl, octadecyl, octadecenyl or other alcohols containing 12 or more carbon atoms at about loll- C. to form the monoester, followed by suli'onating this ester to form the sulfosuccinate. Preferably the sulfonation is carried out by heating the ester with an aqueous solution of sodium sulfite, or sodium metabisulfite, or of the corresponding potassium or ammonium compounds. By this method the alkali metal and ammonium salts of the monoalkyl sulfosuccinic acid esters are obtained directly.

The corresponding salts of ethanolamine and other bases are preferably produced by first acidifying an alcoholic solution of the alkali metal or ammonium sulfosuccinates, whereby the free sulfosuccinic acid monoester is obtained, filtering off the inorganic salt of the acid used and reacting the sulfosuccinic acid ester with the desired base. Salts of other metals such as calcium, barium, zinc, tin, lead and the like are prepared by adding stoichiometric quantities of their oxides or hydroxides to the alcoholic sulfosuccinic acid monoester followed by stirringuntil the salt formation is complete. Salts of organic bases such as methylamine, ethylamine, ethanolamine and the like may also be prepared by the same method.

For many purposes it is desirable to prepare the higher monoalkyl sulfosuccinates in the form of dry, water-dispersible powders. Heretofore this has not been possible, for upon evaporation of their solutions in water or organic solvents the compounds form a white pasty mass similar in texture to ordinary soap. The compounds are precipitated from their aqueous solutions by the addition of ammonium, sodium, or potassium salts, and therefore the addition of sodium or potassium sulfate or chloride to form a dry, freeflowing powder could not be resorted to.

Another important feature of the present invention is the discovery that the solubilizing action of water-soluble chromium salts persists even in the presence of sodium sulfate, sodium chloride and other salts which would ordinarily precipitate the higher monoalkyl sulfosuccinate salts from their water solutions. This discovery has enabled me to prepare dry, free-flowing powders containing the higher monoalkyl sulfosuccinate salts in admixture with water-soluble alkali metal compounds, or in admixture with watersoluble ammonium compounds, which powders are readily soluble in cold water. No material change in the ratio of chromium salt to monoallryl sulfosuccinate salt need be made when other water-soluble salts are added; i. e., the solubilizing action of the chromium salts is the same in the presence of sodium sulfate, sodium chloride and the like as it is in the absence of these salts. However, it has been found that while the upper limit of diluent which may be employed depends entirely on the desired concentration of wetting agent in the dry mixture, the lower limit of diluent is not substantially less than 40% of the mixture. For example, when a dry mix is prepared containing more than about 60% of the monoalkyl sulfosuccinate, the material is not easily soluble in cold water; for this reason dry mixtures containing in excess of about 60% 'of monoalkyl sulfosuccinate are not included within the purview of this invention.

Inpraeticing the invention, the amounts of chromium salts to be employed vary according to the original water solubility of the various monoalkyl sulfosuccinate salts. It will be readily apparent that dodecyl disodium sulfosuccinate, having a water solubility of 4.5 grams per 100 cc., will require the addition of less chromium salt than will disodium hexadecyl sulfosuccinate, for

ill

Per Cent Per Cent Solubility, Solubility, Molar Ratio, gms./l00 cc. gmsJlOO cc. Chromium at 30 0., No at 30 0., to Succinate Chromium Crz(S0|): Salt Salt Addu. Added Dodccyl 4. 5 8 2/511 Dodecyl 4. 5 20 3/5zl Tctradecyl. 0.05 5 3/511 Hexadecyl. 0. 2 10 3 :l Mixture 0. 2 9 315:! Octadccyl. 0.05 2 1:1

The sulfosuccinate mixture above referred to is that prepared from Ammecol.

As is common in the case of the solubility of salts, higher solution temperatures result in an increase of the solubility of the various salts. In the case of the present invention, such variations in solution temperatures permit the use of smaller amounts-of the solubilizing chromium salts. For this reason, the lower limits of such salt additions may in some cases and for some purposes be within the range of from 0.25 mol to 0.5 mol per mol of sulfosuccinate salt employed. On the other hand, while there is no absolute upper limit of chromium salt addition since the solubilizing agent does not interfere with the wetting and detergent properties of the monoalkyl sulfosuccinates, for most commercial applications not more than about 7 to 10 mols of chromium salt should be employed for each mol of sulfosuccinate. Moreover, I have found that the most preferable quantity of chromium salt to be employed is from 0.25 mol to 1 mol for each mol of the sulfosuccinate depending on its water solubility.

Conversely, in preparing aqueous pastes and dry powders containing water-soluble inorganic salts of monovalent metals such as sodium and potassium, larger amount of chromium salts may of course be used, although amounts substantially larger than those given in the above table are not usually necessary.

It is evident, therefore, that the invention in its broader aspects is not limited to the use of large quantities of the chromium salts but that relatively small proportions of these salts may be used if desired.

The invention will be illustrated in greater detail by the following specific examples. It should be understood, however, that although these examples may describe in detail certain specific features of the invention, they are given primaril for purposes of illustration and the invention in its broader aspects is not limited thereto. All parts iven are by weight.

Example 1 A paste was prepared by mixing together 95 parts of a 30% aqueous gel of a disodium monoalkyl sulfosuccinate prepared from Ammecol, and 5 parts of CI2(SO4)3. The paste was used to prepare an aqueous solution containing 9% of the sulfosuccinate salt. The material was completely soluble and the solution remained clear at temperatures of from 6-10 0., whereas the same sul- Example 2 A dry, free-flowing powder was obtained by drying to 100 parts an aqueous mixture consisting of 116 parts of a 30% aqueous gel of the disodium monoalkyl sulfosuccinate mixture employed in Example 1, 6 parts of CI2(SO4)3, and 69 parts of N82SO4. The dried powder formed clear solutions with water when used in concentrations up to 9%.

Example 3 To 100 cc. of a 2% aqueous dispersion of dipotassium cetyl sulfosuccinate was added 7.2 cc. of a 10% CIC13.6H2O solution (1:0.67 molar ratio). Within a short period of time the initially cloudy dispersion became clear, indicating that a true solution of the sulfosuccinate had been obtained.

Example 4 To 100 cc. of a 2% aqueous dispersion of diammonium cetyl sulfosuccinate was added 11.0 cc. of a 10% C1(NO3)3.7H2O solution (1:0.67 molar ratio). Within a short period of time the initially cloudy dispersion became clear, indicating that a true solution of the sulfosuccinate had been obtained.

Example 5 To 100 cc. of a 5% aqueous dispersion of disodium oleyl sulfosuccinate was added 7.5 cc. of a CrClzfiHzO solution (1:0.67 molar ratio). Within a short period of time the initially cloudy dispersion became clear, indicating that a true solution of the sulfosuccinate had been obtained.

It has also been found that chromic bromide suitably solubilize the higher monoalkyl suli'osuccinates similarly to chromic chloride.

Example 6 A W ting and detergent composition 1 t1.

prising essentially a surface active material which is a monoalkyl suliosuccinate having the formula H MOri-COOM COOR in which M i a member of the group consisting of alkali metal and ammonium radicals and both M' are the same, and R is an alkyl radical of from 12 to 18 carbon atoms, and a water-soluble inorganic chromium salt which is capableof increasing the water solubility of the monoalkyl suliosuccinate, said chromium salt being present in an amount the minimum range of which is from 0.25 mol to 1 mol and the maximum amount is 10 mols for each mol of the sulfosuccinate.

2. A wetting and detergent composition comprising essentially a. surface active material which is a mixture of monoalkyl sulfosuccinates having the formula H MOaS.$.COOM

.COOR

in which M is a member of the group consisting of alkali metal and ammonium radicals and both Ms are the same, and R. is an alkyl radical of from 12 to 18 carbon atoms, and a watersoluble inorganic chromium salt which is capable of increasing the water olubility of the mixture of monoalkyl sulfosuccinates, said chromium salt being present in an amount the minimum range of which is from 0.25 mol to 1 mol and the maximum amount is 10 mols for each mol of the sulfosuccinates.

EMIL A. VITALIS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,181,087 Caryl et a1 Nov. 21, 1939 2,316,234 Flett Apr. 13, 1943 OTHER REFERENCES Aerosol Wetting Agents, publication of Amer. Cyanamid and Chem. Corp., N. Y., (1941). DD.

Claims (1)

1. A WETTING AND DETERGENT COMPOSITION COMPRISING ESSENTIALLY A SURFACE ACTIVE MATERIAL WHICH IS A MONOALKYL SULFOSUCCINATE HAVING THE FORMULA