US 3173877 A
Description (OCR text may contain errors)
United States Patent 3,173,877 DETERGENT C(PMPOSITIONS COMPRISING IN- ORGANIC ESTERS 0F EPOXYHYDROCAQN POLYMERS Donald R. Jackson, Ecorse Township, Mich, assignor to Wyandotte Chemicals Corporation, Wyandotte, Mich,
a corporation of Michigan No Drawing. Filed Sept. 9, 1957, Ser. No. 682,600 6 Claims. (Cl. 252-138) This application is a continuation in part of my copending application for Inorganic Esters of Epoxyhydrocarbon Polymers, Serial Number 271,973, filed February 16,. 1952, now abandoned.
The present invention relates to inorganic esters of long chain hydrophobic epoxyhydrocarbon polymers which have valuable surface active properties. More particularly, it relates to detergent compositions comprising said esters.
The art of producing surface active agents is old and well developed, and it is a Well-recognized principle that all such agents are relatively large molecules that contain both hydrophobic and hydrophilic elements. The essential hydrophobic element in the prior art surface active agents has always been a hydrocarbon radical, such as is found in the long chain fatty acids and alcohols, or in the allcylaryl group of the popular alkylarylsulfonate type detergents. The hydrophilic element has frequently been an inorganic acid ester group, such as is found in the long chain alkyl sulfates.
A serious limitation of the prior art surface active agents is that the structure of any particular surface active agent is relatively fixed and it is different to modify it, either as to molecular weight or type. To prepare fatty alcohol-inorganic ester type surface active agents having varying hydrophobic element chain lengths, it is necessary to use as many different base materials as there are variations desired. Among the difficulties inherent in using several :base materials are the storage and handling of many types of complex organic compounds, sup ply problems as to rare homologues, the different reac tion conditions required in preparing the surface active agents, etc., so that it is not feasible to prepare surface active agents which differ from one another in small, uniform increments of hydrophobic element chain length. Similar difiiculties are encountered in preparing petroleum base surface active agents which differ from each other only in small, finite increments of hydrophobic element chain length.
In recent years the desirability of preparing liquid anionic surface active agent compositions having a high proportion of active agent therein has become apparent in the art. The anionic surface active agents heretofore available, such as alkyl sulfates, alkylsulfonates and alkylarylsulfonates have not beenentirely satisfactory for such purpose in that they are normally solids at room temperature and must be dissolved in aqueous solutions, thus reducing the proportion of active agent in the liquid surface active agent composition. In addition, the preparation of such prior art surface active agents requires that an excess of sulfuric acid be used which is subse quently neutralized with caustic soda, thus leaving an undesirably high proportion of inert salt, i.e. Na SO in the final composition. In normal practice, when only stoichiometric quantities of sulfuric acid are used in the preparation of these surface active agents, the resulting product contains an undesirably high proportion of unrcacted base material, or as it is known in the art, unsulfonated oil.
Polyoxyalkylene units have been used heretofore in surface active agents, but perform functions differing diametrically from that performed by the hydrophobic polyoxyalkylene units in the present invention. US.
Patents 2,213,477 and 2,454,542-545 teach the addition of ethylene oxide, propylene oxide, butylene oxide, etc., to hydrophobic alcohols and acids to form the hydrophilic element of nonionic surface active agents. US. 2,203,883 teaches the condensation of alkylphenols with up to 5 equivalents of ethylene oxide, and the subsequent sulfation of the terminal hydroxyl group to prepare surface active agents. In the above teachings, the polyoxyalkalene units have been added to hydrophobic bases to serve as the hydrophilic element of the resulting surface active agents, whereas in the present invention alkylene oxides having prescribed minimum oxygen/ carbon atom ratios are polymerized to critical minimum chain lengths and serve as the primary hydrophobic element of anionic surface active agents.
It is an object of this invention to provide highly active polymeric anionic surface active agents, as well as commercially attractive methods for preparing same.
Another object of this invention is to provide highly active polymeric anionic surface active agents in which the essential hydrophobic element is a polyoxyalkylene chain.
A further object of this invention is to provide highly active polymeric anionic surface active agents in which the essential hydrophobic element is a polyoxypropylene chain.
Still another object of this invention is to provide highly active polymeric anionic surface active agents in which the hydrophobic element can be varied or modified within wide limits, both as to melocular weight and type.
Still another object is to provide the art with detergent compositions comprising said highly active, polymeric, anionic, surface active agents.
Other objects and advantages of this invention will become apparent from the following detailed description thereof.
It has been discovered that organic compounds containing therein a plurality of hydrogen atoms capable of reacting with a 1,2-alkylene oxide can be condensed with a 1,2-alkylene oxide of the formula:
wherein R R R and R are selected from the group consisting of H, aliphatic radicals and aromatic radicals, at least one substituent being a radical other than hydrogen, to prepare epoxyhydrocarbon polymers having the type formula:
wherein Y is the residue of an organic compound containing therein X hydrogen atoms capable of reacting with a l,2-alkylene oxide, R R R and R are selected from the group consisting of H, aliphatic radicals and aromatic radicals, at least one substituent being a radical The surface active agents of this invention have the following formula:
(B) R1 R:
R3 R4 11 x wherein Y is the residue of an organic compound containing therein x hydrogen atoms capable of reacting with a 1,2-alkylene oxide, R R R and R are selected from the group consisting of H, aliphatic radicals and aromatic radicals, at least one substituent being a radical other than hydrogen, n is a number, x has a value of at least 2, the values of n and x are such that the molecular weight of the compound, exclusive of W, is at least 1250, v is a number equal to x-z, W is the monoesterified residue of a polybasic oxygen-containing inorganic acid, and z has a value from 1 to x.
The simplest example of a surface active agent coming within the scope of Formula B is the sulfated ester of a polyoxypropylene glycol of at least 1250 molecular weight. Depending upon reaction conditions, monosulfated esters can be obtained which have the formula:
When more vigorous conditions are used, disulfate esters which have the following formula are obtained:
Returning to a discussion of Formula B, examples of Y include the residue from compounds such as polyhydric alcohols, e.g. ethylene glycol, propylene glycol, glycerine, sorbitol, etc.; dibasic organic acids such as oxalic acid, adipic acid, phthalic acid, etc.; primary amines such as methylamine, butylamine, aniline, etc.; amides such as formamid'e, acetamide, benzoic acid amide, etc.; sulfonamides such as ethane sulfonamide, benzene sulfonamide, etc.; compounds which contain 2 or more functional groups containing active hydrogen atoms such as amino acids, ethanol amines, hydroxy substituted aliphatic and aromatic acids, and other compounds having two or more active hydrogen atoms, as above described. The Y group may also be substituted with groups which do not contain an active hydrogen atom capable of reacting with a 1,2-alkylene oxide, e.g. Cl, Br, NO alkoxy, etc.
In defining R R R and R the terms aliphatic radical and aromatic radical are used in their broad generic sense. The term aliphatic radical includes both. open chain and cylic compounds that are free of benzenoid unsaturation but which may contain ethylenic and/ or acetylenic unsaturation. This definition encompasses compounds such as the cyclopentyl and cyclohexyl radicals. Included within such definition are structures in which two R groups on adjacent carbon atoms are members of a single alkylene ring, an example of such structure being polyoxycyclohexene. The term aromatic radical includes both mononuclear and poly-nuclear aromatics, such as the phenyl radical, the naphthyl radical, the bi- 4 phenyl radical, etc. As in the case of Y, above recited, both the aliphatic radicals and aromatic radicals can be substituted with radicals or groups that do not contain an active hydrogen atom capable of reacting with a 1,2- alkylene oxide. I
Examples of such polyoxyalkylene chains which may be employed are polyoxybutylene, polyoxystyrene, polyoxycyclohexene, etc., and preferably polyoxypropylene.
The above-noted structural formula shows homogeneous polyoxyalkylene chains. While substantially homogeneous polyoxyalkylene chains are the preferred embodiment of this invention, it is to be understood that the polyoxyalkylene chains can be made up of mixtures of monomeric components so long as essentially each monomeric unit conforms to the definitions set forth above. Examples of such heteric structures are those obtained by condensing an active hydrogen compound with a mixture of 1,2-alkylene oxides, e.g. propylene and butylene oxides, amylene and cyclohexene oxides, etc.
It will be recognized in the above-noted definition that at least one R gorup is a radical other than hydrogen, therefore, the oxygen/carbon ratio of the hydrophobic polyoxyalkylene chains is equal to or less than 0.33.
To be sufficiently hydrophobic to serve as the hydrophobic element of the surface active agents of the present invention, the molecular weight of the epoxyhydrocarbon polymer must be at least 1250. It will be seen that the precise value of n required to fulfill this molecular weight requirement is a function of both x (i.e. the number of polyoxyalkylene chains attached to the Y base or stem of the molecule) and the molecular weight of the monomeric oxyalkylene group. In the preferred embodiment of this invention the 1,2-alkylene oxide of the type defined is condensed with a base compound containing two active hydrogen atoms, such as propylene glycol. In this case, when the 1,2-alkylene oxide is propylene oxide, n is at least 20.
The hydrophilic element of the described surface active agents is the monoesterified residue of a polybasic oxygencontaining inorganic acid. Although compounds having desirable surface activity are obtained when fewer than all of the terminal hydroxyl groups are esterified, in the preferred embodiment of the present invention substantially all the terminal hydroxyl groups are so esterified and z in formula B is numerically equal to x and v is zero. Examples of oxygen-containing inorganic acids which may be used to esterify the terminal hydroxyl groups of the epoxyhydrocarbon polymers include boric acid, orthophosphoric acid, pyrophosphoric acid, other condensed phosphoric acids and preferably sulfuric acid. It will be obvious to those skilled in the art that any acidic hydrogen atom in the inorganic acid group may be replaced with a cation ion, such as an alkali metal ion, an ammonium ion, a substitute ammonium ion, etc., and it will be understood that such salts are included within the scope of the appended claims.
Although Formula B adequately describes the bulk of the surface active compounds of this invention, there are a few compounds that require special attention. When the inorganic acid or derivative thereof that is to be esterified with the epoxyhydrocarbon polymer contains 3 or more replaceable acidic hydrogen atoms, it is possible to esterify the inorganic acid group with 2 or more epoxy-- hydrocarbon polymers. For example, when phosphorous oxychloride is esterified with a polyoxypropylene glycol' of greater than 1250 molecular weight, it is possible to.
obtain products having the following type formula:
I? a s)n aHuO)nH O II It is, of course, obvious that the remaining terminal hydroxyl groups of the polyoxypropylene glycol chains can be esterified. Other epoxyhydrocarbon polymers can be used in lieu of a polyoxypropylene glycol in which case the products have the following type formula:
Other oxygen-containing inorganic acids having 3 or more replaceable acidic hydrogen atoms, such as pyrophosphoric acid, other condensed polyphosphoric acids, boric acid, etc., may be used in lieu of orthophosphoric acid or phosphorous oxychloride in preparing such compounds. Thus, these products may be represented by the following general formula:
( R2 R1 R1 R:
wherein A is the residue of an oxygen-containing inorganic acid containing at least 3 replaceable acidic hydrogen atoms; at least 2, but fewer than all of said replaceable acidic hydrogen atoms being esterified by a terminal hydroxyl group of an epoxyhydrocarbon polymer, R R R and R are selected from the group consisting of H, aliphatic radicals and aromatic radicals, at least one substituent being a radical other than hydrogen, n is a number, Y is the residue of an organic compound containing therein x hydrogen atoms capable of reacting with a 1,2- alkylene oxide, x has a value of at least 2, the values of n and x are such that the molecular Weight of the epoxyhydrocarbon polymer portion included within the brackets is at least 1250, and q has a value of at least 2, but less than the total number of replaceable acidic hydrogen atoms in the oxygen-containing inorganic acid of which A is the residue. Compounds in which the terminal hydroxyl groups are esterified with oxygen-containing inorganic acids are included within the scope of Formula C above.
The preparation of the surface active agents of this invention involves tWo basic reactions: (1) the preparation of an epoxyhydrocarbon polymer having a molecular weight of at least 1250 and (2) the esterification of the resulting epoxyhydrocarbon polymer with an oxygencontaining inorganic acid.
In the first step, an organic compound containing'there in two or more hydrogen atoms capable of reacting with a 1,2-a1kylene oxide is condensed with a suitable 1,2-alkylene oxide, viz:
(hereinafter the organic compound containing therein two or more hydrogen atoms capable of reacting with a 1,2- alkylene oxide will be referred to simply as the active hydrogen compound"). In preparing the epoxyhydrocarbon polymer, the condensation of the active hydrogen compound with a suitable 1,2-alkylene oxide is normally carried out at elevated temperatures and pressures in the presence of an alkaline catalyst, such as a sodium alkoxide, a quaternary ammonium base or preferably sodium hydroxide.
Although the reaction may be carried out by simply heating a mixture of the reactants under pressure at a sufficiently high pressure, this procedure is not ordinarily used as the temperatures and pressures required are excessive and the control of the reaction is difiicult. For each molof alkylene oxide reacting an estimated 25 kilogramcalories of heat is liberated which, in the presence of a large quantity of alkylene oxide, may increase the temperature and the reaction rate to such an extent that the reaction assumes an explosive nature.
The preferred method of carrying out the reaction is to add the alkylene oxide to a stirred, heated mixture of the desired active hydrogen compound and alkaline catalyst in a sealed reaction vessel. By adding the 1,2-alkylene oxide to the reaction vessel at such a rate that it reacts as rapidly as added, an excess of 1,2-alkylene oxide is avoided and control of the reaction is simplified. i
The temperature at which the reaction is run will depend upon the particular system in question and especially upon the catalyst concentration used. Generally, at high catalyst concentrations the reaction can be run at lower temperatures and correspondingly lower pressures. The temperatures and pressure required for any given reaction will vary with the active hydrogen compound, the alkylene oxide and the type and concentration catalyst used.
Alternatively, if desired, the 1,2-alkylene oxide may be condensed with a glycol corresponding thereto to prepare a poiyoxyalkylene glycol which may then be reacted with the active hydrogen compound to prepare the epoxyhydrocarbon polymer, viz:
The surface active agents of the present invention are obtained by treating the previously described epoxyhydrocarbon polymer of at least 1250 molecular weight with oxygen-containing inorganic acids, or derivatives thereof, such as acid anhydrides or acid chlorides, to esterify the terminal hydroxyl groups thereof. This esterification may be carried out in the usual manner by treating the epoxyhydrocarbon polymer with chlorosulfonic acid, oleum, sulfur trioxide, sulfuric acid, phosphoric acid, phosphorous oxychloride, boric acid, etc. If desired, the esterification may be carried out in the presence of solvents or diluents while cooling the reaction with external coolants.
It has been observed, however, that where the esterifying agent is an oxygen-containing inorganic acid the reaction reaches an equilibrium and complete esterification of the terminal hydroxyl groups cannot be effected unless the water of esterification is removed from the equilibrium mixture to force the reaction to completion. The water of esterification may be removed by adding dehydrating agents, e.g. (3e01,, alumina, etc., to the reaction mixture or by azeotropic distillation with known entraining agents. The preferred method of carrying out the esterification is to mix the epoxyhydrocarbon polymer and esterification agent and pass them through a falling film evaporator at an elevated temperature and under reduced pressure.
The above-noted difficulties with equilibrium condi tions can be eliminated by using halogenated acids as esterifying agents, e.g. chlorosulfonic acid, phosphorous oxychloride, etc. When using these reagents, a hydrogen halide, normally hydrogen chloride, is formed and is easily expelled from the system by simply heating or by carrying out the reaction under reduced pressure. In the case of sulfations with chlorosulfonic acid, it has been observed that products of improved color and odor properties are obtained when the acid is introduced under the surface of the epoxyhydrocarbon polymer.
Examples 1-8, inclusive, illustrate preferred methods for condensing 1,2-alkylene oxides with active hydrogen compounds.
EXAMPLE 1 Part A Six hundred grams of flaked NaOH and 11,930 grams (157 mols) of propylene glycol were charged into a 25 gallon steel autoclave equipped with a stirrer, thermocouples, pressure gauge and reactant inlet tube whose outlet was directly under the stirrer. The autoclave was purged free of oxygen with dry nitrogen and a total of 62,470 grams (1,075 mols) of 1,2-propylene oxide was added to the reactor over a period of 6 hours at 148 C. while maintaining an average reaction pressure of 10 p.s.i. gauge. The product had a calculated molecular weight 7 Part B The 25 gallon autoclave described in Part A was charged with1l,400 grams (24mo1s) of the product of Part A and 92.5 grams of NaOH. A total of 56,150 grams (970 mols) of 1,2-propylene oxide was added thereto at 150 C. over a 7 hour period while maintaining an average reaction pressure of about 40 psi. gauge. The product had a molecular weight of 1875, as deter- 'mined by hydroxyl number. Since the numerical value of the molecular weight of the epoxyhydrocarbon is somewhat dependent upon the method used in determining same, all molecular weights herein reported, unless otherwise specified, were determined by the method of Ogg et al., Ind. Eng. & Chem, Anal.- Ed. 17, 395 (1945).
EXAMPLES 24 Three polyoxypropylene glycols having the molecular weights set forth in the table below were prepared following the general procedure set forth in Example 1.
Molecular weight Example: polyoxypropylene glycol 2 693 3 1250 EXAMPLE 5 Styrene oxide was added dropwise to a well-stirred solu tion of 1.33 grams of sodium hydroxide and 25.3 grams of propylene glycol. nitrogen atmosphere at 115 C. until a theoretical molecular weight of 226 was obtained. The product was neutralized and stripped to remove water and unreacted styrene oxide. To a solution of 25.3 grams of the above material and 0.89 gram of sodium hydroxide there was added as described above enough styrene oxide equivalent to a total molecular weight of the compound of 916; After neutralization and stripping, a yellow sticky gum was obtained.
EXAMPLE 6 Butadiene monoxide was added to a mixture of 25.3 grams of propylene glycol and 1.33 grams of sodium hydroxide. The oxide was added at 120 C. until a theoretical molecular weight of 179 was obtained. The material was neutralized and stripped to remove water and unreacted oxide. To 25.0 grams of this material and 1.1 grams of sodium hydroxide there was added an amount of butadiene monoxide equivalent to a calculated molecular weight of 569. To 25.0 grams of this material and 0.64 gram of sodium hydroxide there was added still more butadiene oxide to an amount corresponding to a calculatedmolecular weight of 1479. This product was a brown viscous liquid.
EXAMPLE 7 Cyclohexene oxide was added to a solution of 56.5 grams of propylene glycol and 2.98 grams of NaOH at 140 C. until a product having a theoretical molecular weight of 208 was obtained. The product was neutralized and vacuum stripped to remove water and unreacted cyelohexene oxide. To 24.8 grams of the above described material and 5 grams of NaOH was added sufficient cyclohexene oxide at 185 C. to give a product having a theoretical molecular weight of 924. The product was a sticky light brown wax.
EXAMPLE 8 Ninety-six grams of 1,2-butylene oxide was added to a mixture of 25 grams of propylene glycol and 1.3 grams of NaOH over a period of 6.8 hours at 135 C. to prepare a polyoxybutylene glycol having a calculated molecular weight of 368. To 25 grams of the above-described prodnot and 0.28 gram of NaOH was added 50 grams of 1,2-butyle1ie oxide over a period of 16 hours at a reaction temperature of 135 C. The molecular weight of the resulting product was 878.
The addition was carried out in a 8 7 Examples 9-14, inclusive, illustrate preferred methods of esterifying the epoxyhydrocarbon prepared above.
EXAMPLE 9 Four hundred twenty-one grams (0.22 mol) of the product of Example 1, having an average molecular weight of 1875, and 400 ml. of carbon tetrachloride were placed in a glass reaction flask provided with an external cooling bath. Fifty-four grams (0.46 mol) of chlorosulfonic acid was added to the mixture with vigorous stirring over a 9 minute period at C. The mixture was stirred for 48 minutes while maintaining areaction temperature of 0-10 C. and then for another hour While allowing the temperature to rise to about 25 C. The carbon tetrachloride solvent was vacuum distilled at a pot temperature of about 40 C., and thereafter the reaction product was neutralized with 490 ml. of 1.0 N caustic soda. The product was dehydrated by vacuum stripping at a pressure of mm. of mercury and a pot temperature of 40 C. The product was a very viscous reddish colored liquid having a pH of 6.7.
EXAMPLE 10 Two hundred forty grams of the product of Example 4, having an average molecular weight of 1600, and 480 ml. of Stoddard Solvent (ASTM designation number D48440) were placed in a 3-necked 3-li ter round bottom flask equipped with a dropping funnel, stirrer and reflux condenser. Thirty-seven and two-tenths grams (0.362 mol) of sulfuric acid was added to the reaction flask with stirring over a 50 minute period at 25- 30 C. Stoddard Solvent and Water were then distilled from the reaction mixture at a pressure of 6-12 mm. of mercury while maintaining a pot temperature of 38-57 C., thus azeotropically removing the water of sulfation. During the distillation an additional 480 ml. of Stoddard Solvent was added to the reaction mixture, and the entire distillation required 2.7 hours. The reac tion product was neutralized with an aqueous solution containing 28 grams of NaOH, and the neutralized product was dehydrated by heating to 60-70 C. under a pressure of about 10 mm. of mercury. The resulting product was a viscous syrup-like material that was miscible in all proportions with water.
EXAMPLE 11 Two hundred fifty-six grams (0.16 mol) of the product of Example 4, having an average molecular weight of 1600, and 49.8 grams (0.48 mol) of 95% sulfuric acid were placed in a one-neck one-liter round bottom flask. This mixture was heated to 35-46 C. for 1.7 hours under a pressure of 2-30 mm. of mercury. The sulfation mixture was then transferred to a falling film stripping apparatus which consisted of: (1) a one-liter reactant reservoir having a stop-cock and delivery tube, (2) a 24-inch 12-bulb Allihn condenser, and (3) a one-liter reactant receiving vessel having a side-arm. The pressure in the apparatus was reduced to 6 mm. of mercury and the sulfation mixture was passed through the stripping column in 2.5 hours, while passing steam through the condenser jacket. The yield of sulfated' product before neutralization was 298- grams. A' 252 gram portion of the sulfation mixture was neutralized with 26 grams of NaOH that were dissolved in 714 m1. of water, and the resulting solution contained 26.4% of the sodium disulfate of a polyoxypropylene glycol having a molecular weight of 1600.
EXAMPLE 12 The product of Example 2 was sulfated with chlorosulfonic acid following the procedure of Example 9.
EXAMPLE 13 The product of Example 3 was sulfated following the procedure of Example 9.
9 EXAMPLE 14 One hundred sixty grams (0.1 mol) of the product of Example 4, having an average molecular weight of 1600, and 640 grams of carbon tetrachloride were placed in a S-neck 3-liter flask equipped with a stirrer, thermometer, condenser, dropping funnel and provided with external cooling and heating means. The flask was cooled to C. and 30.7 gnams (0.17 mol) of phosphorous oxychloride was added thereto. The temperature was then raised to 75 C. over a period of one hour, and thereafter the contents were refluxed at 7573 C. for 0.5 hour. The carbon tetrachloride was removed by vacuum distillation at a temperature not exceeding 42 C. and 178 grams of product was recovered. The product was neutralized with aqueous caustic and dehydrated by vacuum distillation to recover 196 grams of the sodium diphosphate of polyoxypropylene glycol having a molecular weight of 1600, which was a resin-like solid.
The following test procedure were used to evaluate the surface active properties of the products of this invention:
CARBON SOIL REMOVAL TEST PROCEDURE A standard soiled cotton fabric is first prepared as follows:
Bleached, unfinished Indian Head muslin (58 x 47,
4.7 oz. per sq. yd., manufactured by Textron, Inc), is
used without pretreatment after conditioning to equilibrium at 65% RH. and 70 F. A continuous /2 inch wide strip of themuslin is soiled by passing through an emulsion of colloidal carbon black and water-soluble mineral oil. After thorough impregnation of the standard muslin in the carbon black and oil emulsion, the cloth is passed through a power-driven household-type wringer to squeeze out any residual aqueous dispersion, the wringer pressure being so adjusted as to leave in the cloth an amount of standard soil dispersion equal to 120i5% of the dry weight of the cloth. The soiled muslin is then passed through a brush arrangement which by means of its mechanical action on the cloth controls the removability characteristics of the soil. The soiled muslin or test cloth is then dried, first in festoon under atmospheric conditions and then in an electrically heated, forced draft oven. After drying, the :cloth is aged for 4 to 6 days by hanging in an atmosphere of 65% RH. at 70 F. after which it is cut into test swatches measuring 2.5 inches il inch by 3.5 inches inch using a power driven guillotine paper cutter. Before actual use of the so-prepared standard soiled cloth, it is checked for conformance with acceptability limits by the follow ng described carbon soil removal test in standard detergent solutions. The swatches are stored at 65% RH. and 70 F. prior to use.
To evaluate the soil removal characteristics of synthetic detergent compositions, 0.25% by weight solutions or other desired concentrations of the composition to be tested are prepared in water and 100 ml. portions of such solution are added to each of 10 one-pint jars of a Launder-Ometer (type l2QEF-SPA, manufactured by Atlas Electric Devices Company) standard laundry test machine.
Fifteen /4" diameter stainless steel balls are placed in each jar, after which two pieces of the previously prepared standard soiled cloth are added to each of nine. jars. In the tenth jar are placed two pieces of unsoiled but pretreated cloth and this latter jar serves as a blank for determining the turbidity of the detergent solution. The so-prepared jars, heated to a temperature of l40i2 F. in a constant temperature bath are then placed in the Launder-Ometer and run for 10 minutes at a speed of 42:2 r.p.m. The jars are then removed from the test machines and replaced in the constant temperature bath.
The contents of each jar to which the standard soiled cloth has been added are poured through a coarse screen to separate the steel balls and the standard soiled cloth from the soil suspension which is collected in a large beaker. The composite suspension thus attained is mixed thoroughly and a sample placed in a 20 mm. light absorption cell. The light absorption of this composite solution, as well as the light absorption of the solution in the tenth or blank jar containing the unsoiled cloth test pieces is then measured (by a Lumetron Colorimeter). By means of a calibration curve for the Lumetron Colorimeter, such curve being constructed by obtaining light transmission readings of known quantities of carbon black dispersion added to distilled water, the carbon soil removal value sought (in mg. of carbon per liter of solution) is obtained by taking the difference between the converted values of the light transmission of the composite solution or suspension from the nine jars and of the light transmission of the suspension in the blank jar.
The carbon soil removal values are then reported as a percentage of that of a standard detergent solution used as a reference or control material; viz. by dividing the mg. of carbon removal value of the test material composition by the mg. of carbon removal value for the standard or control detergent solution which is determined concurrently in the same test run and on the same standard soiled test cloth, and multiplying by 100.
The standard detergent solution used throughout the tests reported herein was a 0.25% solution of sodium kerylbenzene sulfonate in distilled water. The sodium kerylbenzene sulfonate was prepared by effecting a Friedel-Crafts condensation of a chlorinated petroleum hydrocarbon distillate (derived from a hydrocarbon distillate having 9-16 carbon atoms and boiling in the range of ISO-300 C.) with benzene and thereafter sulfonating the kerylbenzene compound to form the kerylbenzene sulfonic acid, which was subsequently neutralized with caustic soda to form the water-soluble sodium kerylbenzene sulfonate. After the neutralization of the sulfonic acid, sufiicient sodium sulfate was added so that the final product contained 40% sodium kerylbenzene sulfonate and 60% sodium sulfate.
WHITENESS RETENTION TEST PROCEDURE Bleached, unfinished, clean Indian Head muslin, count 58 x 47, weight 4.7 oz./sq. yd. (Textron, Inc), is cut 7 into swatches measuring 2 /2" x 3 /2". The light reflectance of each side of every swatch is measured by means of a Hunter Multipurpose Reflectometer equipped with a green filter, using 7 test swatches and a standard plaque with a reflectance of 68.8 as a backing behind the swatch. The average of such values of each. side of each test piece is calculated and recorded. A standard soil suspension is prepared by diluting 28.55 grams of an aqueous carbon dispersion containing 35% carbon (Aqua Blak B, Binney and Smith Co.) with distilled water to 1 liter.
A 0.25% water solution (or other desired concentrations) of the detergent compound to be tested is then made up by adding 2.5 grams of the compound to a small amount of water in a 1 liter volumetric flask. The previously prepared soil suspension is shaken vigorously and 50 ml. then pipetted into the flask containing the detergent. Sufficient water is then added to this flask to make up to the one-liter mark.
The resultant mixture of detergent and carbon soil suspension is pipetted in ml. portions into each of 5 Launder-Ometer jars, each jar containing fifteen 4" stainless steel balls. The jars and contents are brought to a temperature of :2 F. in a constant water bath, then placed in the Launder-Ometer and rotated for 5 minutes at 4212 r.p.m. The Launder-Ometer is then stopped and without removing the jars from the machine, the lids are opened and two standard cloth swatches, prepared as previously described, are placed in each jar after soaking for exactly 1 minute in distilled water without subsequent draining. The lids are replaced on the jars and the latter are rotated for an additional 30 minutes in the Launderl l. Ometer. The swatches are then removed and immediately rinsed by flowing 3 liters of distilled water continuously through a rinsing flask for a period of 5 minutes while shaking. Immediately after rinsing, the swatches are removed from the rinsing flask and placed on flat clean paper towels. The swatches are then placed flat on a steel plate and dried in an electrically heated oven at 105 C. until dry to minutes). After drying, the reflec tance of both sides of each swatch is again measured by the Hunter Reflectometer and the average reflectance of all swatches calculated and recorded. The whiteness retention value is then calculated as follows:
Percent whiteness retention (W.R.)
Ave. reflectance after soiling 100 Ave. reflectance before soiling Eight hundred eighty grams (0.55 mol) of the epoxyhydrocarbon polymer of Example 4, having an average molecular weight of 1600, was placed in a three-necked 3- liter flask equipped with a stirrer, thermometer and dropping funnel, and provided with external cooling and heating means. The outlet of the dropping funnel was a fine capillary which extended below the surface of the liquid and the reaction flask was connected to a vacuum system. One hundred forty-one grams (1.21 mols) of chlorosulfon'ic acid was added to the stirred solution over a period of 1.5 hours while maintaining a reaction temperature of about 15 C. Throughout the chlorosulfonic acid addition, HCl was removed by maintaining the system under the vacuum drawn with a water aspirator, i.e. 20-25 mm. Hg. Thereafter, the system was connected to a vacuum pump and maintained under a pressure of 7-25 mm. Hg for one hour to remove the final traces of HCl. The product was neutralized with 222 ml. of 6.5 N NaOH to prepare an aqueous solution of the product having a pH of 8. A 0.1% solution of the product had a carbon soil removal value of 118 and a whiteness retention value of 260, both values being obtained at 140 F.
EXAMPLE 16 The sulfated products of Examples 9, 12 and 13, which differed from one another in the molecular weight of epoxyhydrocarbon polymer portion thereof, were evaluated for carbon soil removal and whiteness retention properties by the heretofore described methods. The data obtained with 0.25% solution in distilled water are set forth in Table I, below:
Table l soil removal and Whitness retention values increase with the molecular weight of the epoxyhydrocarbon polymer portion of the surface active agent. To obtain satisfactory detergency properties, the molecular weight of the enoxyhydrocarbon polymer portion must be at least 1250.
12 EXAMPLE 17 Carbon soil removal values of the sulfated product of Example 9 were determined at various concentrations.
The data are shown in Table II, below:
Table 11 Carbon soil removal at F. 0.25% solution Surface active agent concentration, percent:
Referring to Table II, it will be seen that carbon soil removal values increase with surface active agent concentration in a nearly linear relationship over the range of concentrations studied.
EXAMPLE 18 The phosphated product of Example 14, as evaluated by the heretofore described methods, had a carbon soil removal value of 131% and a whiteness retention value of 240%, when tested at 140 F. and in an 0.25% aqueous solution.
The surface active agents of this invention may be combined with inorganic builders, carboxymethylcellulose or combinations thereof to prepare compounded detergents which have excellent properties. Typical formulations of such compounded detergents are set forth in Examples 19-21.
EXAMPLE 19 Binary combinations of the product of Example 9 and sodium sulfate and modified soda (a mixture of Na CO and NaHCO having a total alkalinity as Na O of 39- 43%. See ASTM designation: D45739) were evaluated for carbon soil removal, and the data are shown in Table III, below:
Table III Carbon Soil Test No. Detergent Composition Removal at 0.1% Prod. Example 9 131 0.1% Prod. Example 9+0.15%
Nags 4. 0.1% Prod. Example 9+0.15% 1G6 Modified Soda.
It will be seen from Table III that the incorporation of an inorganic builder in the surface active agents of this invention effects a substantial promotion of the detergency thereof.
EXAMPLE 20 Binary combinations of the surface active agent of Example 9 and carboxymethylcelulose were evaluated for carbon soil removal and the results are shown in Table IV, below:
Referring to tests 2, 3 and 4 of Table IV, it will be noted that, at a uniform concentration of surface active agent, the carbon soil removal value increases with the concen- 13 tration of carboxymethylcellulose incorporated into the binary combination. Similarly, referring to tests 4 and 5, it is seen that an increase of surface active agent concentration at a constant level of carboxyrnethylcellulose increases the carbon soil removal value of the binary com- 5 bination.
EXAMPLE 21 Ternary detergent composition comprising the surface active agents of this invention, an inorganic builder and carboxymethylcellulose were evaluated for carbon soil removal and whiteness retention properties in distilled and grain/gallon water (Bureau of Ships Specification 51-C-49, Nov. 1, 1948. CaCl equivalent to 2.85 grams CaCO per liter; MgCl equivalent to 1.2 grams MgCO per liter; this stock solution containing 4275 p.p.rn. hardness expressed as CaCO diluted to 15 grains/ gallon) at 140 F. The results are shown in Table V, below:
The foregoing table shows that alkaline materials do inhibit hydrolysis of the esters of this invention.
Thus, not only may builders be used to enhance the It will be seen from Table V that the ternary compositions containing both an inorganic builder and carboxymethylcellulose have higher carbon soil removal values than those obtained with any of the binary combinations illustrated in Examples 19 and 20. Of particular interest are the carbon soil and whiteness retention values 4 obtained in 15 grains/gallon water. It is well known in the detergent art that hard water drastically reduces the detergency of most detergent compositions. However, the compositions illustrated in tests 2 and 3 have excellent detergency properties even in extremely hard water.
In addition to their detergency properties, the surface active agents of the present invention have excellent wetting action. For example, an 0.3% solution of the product of Example 9 had a Draves Sink Time of 22 seconds when measured with a 3 gram hook. The Draves Sink Time is a measure of the wetting action of the compound tested, and the method is fully described in The Technical Manual and Yearbook of the American Association of Textile Chemists and Colorists, 25, 143-145 (1949).
The surface active agents of the present invention tend to hydrolize in aqueous solution. However, by incorporating alkaline materials, such as alkaline builders, into the solution, the hydrolysis may be minimized.
To illustrate this the following Example 22 is set forth.
EXAMPLE 22 To each of four 350 gram samples of 54.8 weight percent solutions of the sodium d-isulfate ester of polyoxypropylene glycol having a molecular weight of 1700 was added 7.7 grams of a builder dissolved in 33.6 ml. of water. The builders were Quadrafos (Na P O sodium pyrophosphate (Na P O trisodium phosphate monohydrate (Na PO -H O) and sodium hydroxide. The resulting by weight solutions with 2% by weight builder, and a 50% by weight solution without a builder, were kept in an oven at 50-54 C. for 100 days. The pH of two gram samples dissolved in 25 ml. of water was measured at intervals. The measurements are set forth in the following table. 75
Table V Surfactant Distilled Water 15 Grain Water Test No. Detergent Composition Wt. Percent Builder Dry Basis Ratio,
Pt./Wt. CSR WR CSR WR 36 40 55 60 0.025% Sodium Carboxy- 9 246 215 215 207 methylcellulose. 3 0.1% Prod. Example 9 36 40 051.2% Sodium Tripolyphos- 55 00 p a e. 0.025% Sodium Carboxy- 9 290 212 279 209 methylcellulose.
detergencyproperties of the esters of this invention, but also maybe used to inhibit their hydrolysis in aqueous solution. As a further example of built detergency, the following results were obtained in accordance with the hereinbefore described procedures.
Thus, the surface active agents of this invention in combination with alkaline detergency builders have excellent detergency properties.
In light of the foregoing, this invention also comprises heavy duty detergent compositions containing as ingredients (l) a polyoxypropylene glycol disulfate having a molecular weight from about 1000 to 3000, and most advantageously, from about 1500 to 21500, and (2) a phosphate builder salt capable of acting as a sequestering agent for hard water ions. Preferably, in such compositions, the polyoxypropylene glycol disulfate should comprise about 10 to 40 parts by weight of the composition and the alkaline, water-soluble, calcium-sequestering, phosphate salt builder should comprise from to 60 parts by weight. An example of a surface-active polyoxypropylene glycol is disodium polyoxypropylene glycol disulfate and an example of said phosphate salt builder is sodium tripolyphosphate.
What is claimed is:
1. An aqueous detergent solution comprising from about 0.1% to about 0.25% by weight of disodium polyoxypropylene glycol disulfate wherein the polyoxypropylene base has an average molecular weight of at least 1250 as determined by hydroxyl number, and about 0.005% to about 0.025% by weight of sodium carboxymethylcellulose and balance water.
R1 R2 1 I Y I(|J H,.W, Ra Ra n x wherein Y is the residue of an organic compound containing therein x hydrogen atoms capable of reacting with a l,2'alkylene oxide, R R R and R are selected from the group consisting of H, aliphatic radicals and aromatic radicals, at least one such substituent being a radical other than hydrogen, n is an integer, x is at least 2, the value of n and x are such that the molecular weight of the compound, exclusive of W, is at least 1250, v is a number equal to x-z, W is the monoesterified residue of a poly-basic oxygen-containing inorganic acid, and z has a value from 1 to x, and sodium carboxymethylcellulose and having an inorganic ester to sodium carboxymethylcellulose ratio ranging from about 4:1 to 20: 1.
5. A detergent composition comprising an inorganic ester of an epoxyhydrocarbon polymer having the type wherein Y is the residue of an organic compound containing therein x hydrogen atoms capable of reacting with a 1,2-alkylene oxide, one member of the group consisting of R and R is a methyl radical and the other is a hydrogen atom, n is an integer, x is at least 2, the value of n and x are such that the molecular Weight of the compound, exclusive of is at least 1250, v is a number equal to xz, and z has a value from 1 to x, and sodium carboxymethylcellulose and having an inorganic ester to sodium carboxymethylcellulose ratio ranging from about 4:1 to 20:1.
6. An aqueous detergent solution comprising about 0.1% by weight disodium polyoxypropylene glycol disulfate wherein the polyoxypropylene base has an average molecular weight of 1876 as determined by hydroxyl number, about 0.15% by weight sodium tripolyphosphate and about 0.025% by weight of sodiumcarboxymethylcellulose and balance water.
References Cited in the file of this patent UNITED STATES PATENTS 1,970,578 Schoeller Aug. 21, 1934 2,213,477 Steindortf Sept. 3, 1940 2,486,921 Byerly Nov. 1, 1949 2,677,700 Jackson et al. May 4, 1954 2,755,296 Kirkpatrick July 17, 1956 2,802,789 Stayner Aug. 13, 1957 UNITED STATES :PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,173,877 March 16, 1965 Donald R. Jackson It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.
Column 1, line 33, for "different" read difficult line 41 for "problems" read problem column 2, line 37, for "melocular" read molecular column 9, line 19, for "procedure" read procedures column 12, line 12, for "0.025---89" read 0.250-206 column 13, line 8,
for "composition" read compositions Signed and sealed this 15th day of March 1966.
ERNEST W. SWIDER BRENNER Attesting Officer Commissioner of Patents