TREATED OVERBASED COMPLEXES
United States Patent 3714042
Treat overbased complexes with high molecular weight aliphatic carboxylic acids, anhydrides, esters, amides, imides, or salts. The treated overbased complexes may be used as additives in lubricating oils, gasolines, and other organic materials.
US Patent References:
Basic metal-containing thickened oil compositions
McMillen - March 1966 - 3242079
/3219666.html
Norman et al. - November 1965 - 3219666
Composition
Le Suer - March 1968 - 3374174
Polymerized olefin substituted succinic acid esters
Le Suer - April 1968 - 3381022
Friction-modified clutch fluids
Tunkel et al. - November 1968 - 3410801
Basic metal-containing thickened oil compositions
McMillen - March 1966 - 3242079
/3219666.html
Norman et al. - November 1965 - 3219666
Composition
Le Suer - March 1968 - 3374174
Polymerized olefin substituted succinic acid esters
Le Suer - April 1968 - 3381022
Friction-modified clutch fluids
Tunkel et al. - November 1968 - 3410801
Application Number:
05/008701
Publication Date:
01/30/1973
Filing Date:
02/04/1970
View Patent Images:
Export Citation:
Assignee:
The Lubrizol Corporation (Wickliffe, OH)
Primary Class:
Other Classes:
44/330, 44/331, 508/460, 44/373
International Classes:
C08F8/44; C10M159/20; C10M159/24; C08F8/00; C10M159/00; C10M1/24; C10M1/40; C10M3/24
Field of Search:
252/18,39,34,41,34.7,51.5A,40.5,40.7,42.1,42,33.4,33.2,389 44/51
Primary Examiner:
Wyman, Daniel E.
Assistant Examiner:
Vaughn I.
Parent Case Data:
This application is a continuation-in-part of copending application Ser. No. 811,204, filed Mar. 27, 1969, now abandoned.
Claims:
what is claimed is
1. A composition prepared by a process comprising mixing (A) a basic metal complex selected from the class consisting of sulfonate, sulfonate-carboxylate and carboxylate complexes with up to an amount equivalent to the total basicity thereof of (B) a high molecular weight aliphatic carboxylic acid or anhydride wherein there are at least about 25 aliphatic carbon atoms per carboxy group in (B) at a temperature of from about 25°C to the decomposition temperature of the process mass.
2. The composition of claim 1 wherein the metal is a Group II metal.
3. The composition of claim 2 wherein the basic metal complex is derived from an alkylated aryl sulfonic acid having at least about 15 aliphatic carbon atoms.
4. The composition of claim 3 wherein the carboxylic acid or anhydride of (B) is a polybutene substituted succinic acid or anhydride wherein the polybutene substituent has an average of at least about 50 carbon atoms and the amount thereof is from about 0.1 to about 10 percent by weight of the complex of (A).
5. The composition of claim 4 wherein the carboxylic acid or anhydride is a polyisobutenyl having a molecular weight from about 700 to about 5,000, succinic acid or anhydride and the amount thereof is from about 3 to about 5 percent by weight of the complex of (A).
6. The composition of claim 5 wherein the complex of (A) has a base number of at least about 70.
7. The composition of claim 6 wherein the complex of (A) is a basic calcium sulfonate complex.
8. The composition of claim 7 wherein the basic calcium sulfonate complex is a mixture of (a) a carbonated, basic calcium alkylated benzene sulfonate having a base number of about 400 and (b) a carbonated, basic calcium alkylated benzene sulfonate having a base number of about 80 in which the weight ratio of (a) to (b) is from about 10:1 to about 1:1.
9. The composition of claim 6 wherein the complex of (A) is a carbonated, basic magnesium sulfonate-carboxylate complex having a base number of from about 300 to about 500 and the temperature is from about 50°C to about 150°C.
10. A composition prepared by a process comprising mixing (A) a basic metal complex selected from the class consisting of sulfonate, sulfonate-carboxylate and carboxylate complexes with (B) at least one member of the group consisting of substantially saturated hydrocarbon-substituted carboxylic acids, having at least about 25 aliphatic carbon atoms in the hydrocarbon substituent per carboxy group and the anhydrides, esters, ammonium salts, amine salts, amides, and imides thereof at a temperature of from about 50°C to the decomposition temperature of the process mass, wherein the amount of the carboxylic acid or anhydride used is an amount equivalent to up to 40 percent of the basicity of the complex of (A), and the amount of the ester, ammonium salt, amine salt, amide, and imide derivative of the carboxylic acid used is an amount equivalent to at least 1 but no more than 25 percent of the basicity of the complex of (A).
11. A process comprising the mixing of (A) a basic metal complex selected from the class consisting of sulfonate, sulfonate-carboxylate and carboxylate complexes with up to an amount equivalent to the basicity thereof of (B) a high molecular weight aliphatic carboxylic acid or anhydride wherein there are at least about 25 aliphatic carbon atoms per carboxy group in (B) at a temperature of from about 25°C to the decomposition temperature of the process mass.
12. A lubricating composition comprising a major proportion of a lubricating oil and a minor foam reducing proportion of the composition of claim 1.
13. A lubricating composition comprising a major proportion of a lubricating oil and a minor foam reducing proportion of the composition of claim 7.
14. A lubricating composition comprising a major proportion of a lubricating oil and a minor foam reducing proportion of the composition of claim 8.
15. A lubricating composition comprising a major proportion of a lubricating oil and a minor foam reducing proportion of the composition of claim 9.
16. The composition of claim 1 further characterized in that the temperature ranges from about 50°C. and below 250°C.
17. The lubricating composition of claim 12 further characterized in that said lubricating oil contains about 0.1 to about 20% by weight of the composition.
1. A composition prepared by a process comprising mixing (A) a basic metal complex selected from the class consisting of sulfonate, sulfonate-carboxylate and carboxylate complexes with up to an amount equivalent to the total basicity thereof of (B) a high molecular weight aliphatic carboxylic acid or anhydride wherein there are at least about 25 aliphatic carbon atoms per carboxy group in (B) at a temperature of from about 25°C to the decomposition temperature of the process mass.
2. The composition of claim 1 wherein the metal is a Group II metal.
3. The composition of claim 2 wherein the basic metal complex is derived from an alkylated aryl sulfonic acid having at least about 15 aliphatic carbon atoms.
4. The composition of claim 3 wherein the carboxylic acid or anhydride of (B) is a polybutene substituted succinic acid or anhydride wherein the polybutene substituent has an average of at least about 50 carbon atoms and the amount thereof is from about 0.1 to about 10 percent by weight of the complex of (A).
5. The composition of claim 4 wherein the carboxylic acid or anhydride is a polyisobutenyl having a molecular weight from about 700 to about 5,000, succinic acid or anhydride and the amount thereof is from about 3 to about 5 percent by weight of the complex of (A).
6. The composition of claim 5 wherein the complex of (A) has a base number of at least about 70.
7. The composition of claim 6 wherein the complex of (A) is a basic calcium sulfonate complex.
8. The composition of claim 7 wherein the basic calcium sulfonate complex is a mixture of (a) a carbonated, basic calcium alkylated benzene sulfonate having a base number of about 400 and (b) a carbonated, basic calcium alkylated benzene sulfonate having a base number of about 80 in which the weight ratio of (a) to (b) is from about 10:1 to about 1:1.
9. The composition of claim 6 wherein the complex of (A) is a carbonated, basic magnesium sulfonate-carboxylate complex having a base number of from about 300 to about 500 and the temperature is from about 50°C to about 150°C.
10. A composition prepared by a process comprising mixing (A) a basic metal complex selected from the class consisting of sulfonate, sulfonate-carboxylate and carboxylate complexes with (B) at least one member of the group consisting of substantially saturated hydrocarbon-substituted carboxylic acids, having at least about 25 aliphatic carbon atoms in the hydrocarbon substituent per carboxy group and the anhydrides, esters, ammonium salts, amine salts, amides, and imides thereof at a temperature of from about 50°C to the decomposition temperature of the process mass, wherein the amount of the carboxylic acid or anhydride used is an amount equivalent to up to 40 percent of the basicity of the complex of (A), and the amount of the ester, ammonium salt, amine salt, amide, and imide derivative of the carboxylic acid used is an amount equivalent to at least 1 but no more than 25 percent of the basicity of the complex of (A).
11. A process comprising the mixing of (A) a basic metal complex selected from the class consisting of sulfonate, sulfonate-carboxylate and carboxylate complexes with up to an amount equivalent to the basicity thereof of (B) a high molecular weight aliphatic carboxylic acid or anhydride wherein there are at least about 25 aliphatic carbon atoms per carboxy group in (B) at a temperature of from about 25°C to the decomposition temperature of the process mass.
12. A lubricating composition comprising a major proportion of a lubricating oil and a minor foam reducing proportion of the composition of claim 1.
13. A lubricating composition comprising a major proportion of a lubricating oil and a minor foam reducing proportion of the composition of claim 7.
14. A lubricating composition comprising a major proportion of a lubricating oil and a minor foam reducing proportion of the composition of claim 8.
15. A lubricating composition comprising a major proportion of a lubricating oil and a minor foam reducing proportion of the composition of claim 9.
16. The composition of claim 1 further characterized in that the temperature ranges from about 50°C. and below 250°C.
17. The lubricating composition of claim 12 further characterized in that said lubricating oil contains about 0.1 to about 20% by weight of the composition.
Description:
This invention relates to new compositions of matter, processes for preparing same, and lubricating compositions containing same. Particularly, it relates to the treatment of basic metal sulfonate complexes, sulfonate-carboxylate complexes and carboxylate complexes with high molecular weight carboxylic acids or derivatives thereof and the products resulting from said treatment. It relates also to the reduction of the foaming tendency of lubricating compositions containing these basic metal complexes.
Basic metal complexes are well-known in the art. They are of utility as lubricant additives, paint-dryers, stabilizers for plastics, emulsifiers, rust preventives and the like. They are especially valuable because of their detergent or dispersant properties and their ability to neutralize undesirable acidic bodies formed in, e.g., crankcase lubricants under service conditions. For this reason they are one of the most commonly used lubricant additives. The incorporation of basic complexes into lubricating compositions in some cases gives rise to problems. Among these problems is the greater tendency of lubricating compositions containing detergent additives to foam. Another problem is that the lubricant compositions tend to form haze on standing.
It is, therefore, a principal object of this invention to provide basic metal complexes having a reduced tendency to cause foam in lubricants.
A further object is to provide basic metal complexes having improved oil-solubility.
Another object of this invention is to provide lubricating compositions containing an improved basic metal complex.
Another object is to provide a method of treating basic metal complexes to improve the foam and solubility properties thereof.
Further objects of this invention will become apparent from the following description thereof.
These objects are attained by a composition prepared by mixing (A) a basic metal complex selected from the class consisting of sulfonate, sulfonate-carboxylate and carboxylate complexes with up to an amount equivalent to the total basicity thereof of (B) high molecular weight aliphatic carboxylic acid or anhydride wherein there are at least about 25 aliphatic carbon atoms per carboxy group in (B) at a temperature of from about 25°C to the decomposition temperature of the process mass.
As used in the present specification and claims, the term "complex" refers to basic metal salts which contain metal in an amount in excess of that present in a neutral or normal metal salt. The "metal ratio" characterizing a complex is thus the ratio of the total equivalents of metal to the equivalents of metal in the form of neutral or normal metal. The "base number" of a complex is the number of milligrams of KOH to which one gram of the complex is equivalent as measured by titration.
The metal of the complexes may be a Group I or Group II metal such as sodium, potassium, lithium, magnesium, strontium, barium, or calcium. An alkaline earth metal, especially calcium, barium, or magnesium is preferred.
Basic metal complexes are known in the art. Those which are contemplated herein include complexes derived from oil-soluble sulfonic acids, oil-soluble carboxylic acids, and mixtures thereof, such as are described in U.S. Pat. Nos. 2,501,731; 2,616,904; 2,616,905; 2,616,906; 2,616,911; 2,616,924; 2,616,925; 2,617,049; 2,777,874; 3,027,325; 3,256,186; 3,282,835; 3,384,585; 3,373,108; 3,365,396; 3,342,733; 3,320,162; 3,312,618; and 3,318,809. For purposes of illustration, the disclosures of the above patents are hereby incorporated in the present specification insofar as the complexes useful in this invention are described.
As an example of a particularly convenient process for the preparation of the complexes used, an oil-soluble sulfonic acid, such as a synthetically prepared didodecylbenzene sulfonic acid, is mixed with an excess of lime (e.g., 10 equivalents per equivalent of the acid) and a promoter such as methanol, heptylphenol, or mixture thereof, and a solvent such as mineral oil, at 50°C-150°C and the process mass is then carbonated until a homogeneous mass is obtained. Complexes of sulfonic acids, carboxylic acids, and mixtures thereof are obtainable by processes such as are described in U.S. Pat. No. 3,312,618. Another example is the preparation of a magnesium sulfonate complex by carbonating a mixture of a sulfonic acid or normal magnesium salt thereof, an excess of magnesium oxide, water, and preferably also an alcohol such as methanol.
The carboxylic acids useful for preparing sulfonatecarboxylate complexes, and carboxylate complexes, i.e., those obtainable from processes such as the above wherein a mixture of sulfonic acid and carboxylic acid or a carboxylic acid alone is used in lieu of the sulfonic acid, are oil-soluble acids and include primarily fatty acids which have at least about 12 aliphatic carbon atoms and not more than about 24 aliphatic carbon atoms. Examples of these acids include: palmitic, stearic, myristic, oleic, linoleic, dodecanoic, behenic, etc. Cyclic carboxylic acids may also be employed. These include aromatic and cyclo-aliphatic acids. The aromatic acids are those containing a benzenoid structure (i.e., benzene, naphthalene, etc.) and an oil-solubilizing radical or radicals having a total of at least about 15 to 18 carbon atoms, preferably from about 15 to about 200 carbon atoms. Examples of the aromatic acids include: stearyl-benzoic acids, phenyl stearic acid, mono- or polywax-substituted benzoic or naphthoic acids wherein the wax group consists of at least about 18 carbon atoms, cetyl hydroxybenzoic acids, etc. The cyclo-aliphatic acids contemplated have at least about 12, usually up to about 30 carbon atoms. Examples of such acids are petroleum naphthenic acids, cetyl cyclohexane carboxylic acids, di-lauryl decahydronaphthalene carboxylic acids, di-octyl cyclopentane carboxylic acids, etc. The thiocarboxylic acid analogs of the above acids, wherein one or both of the oxygen atoms of the carboxyl group are replaced by sulfur, are also contemplated.
The ratio of the sulfonic acid to the carboxylic acid in mixtures is at least 1:1 (on a chemical equivalent basis) and is usually less than 5:1, preferably from 1:1 to 2:1.
In general, complexes having metal ratios from 1.1 to about 30 are contemplated for use in the present invention. Those having metal ratios ranging from 2 to 20 are preferred.
An important aspect of the present invention is the treatment of a complex, after it is formed, with a high molecular weight carboxylic acid or anhydride or an acid-producing derivative thereof. By "high molecular weight carboxylic acid" is meant an aliphatic acid wherein there is an average of at least about 25 aliphatic carbon atoms per carboxy radical. Such acids are exemplified by alkanoic and alkenoic acids as well as polar-substituted alkanoic or alkenoic acids. They may be either acyclic or cyclic and may contain aryl substituents. The polar substituents may be chloro, bromo, iodo, ether, nitro, or the like. The acids may contain one or more carboxy radicals, and may thus be dicarboxy, tri-carboxy, or tetracarboxy acids such as substituted succinic acids, maleic acids, malonic acids, etc. Examples of preferred high molecular weight carboxy acids are those described in U.S. Pat. No. 3,219,666, the disclosure of which, particularly that at column 6, line 47 to column 7, line 55, is hereby incorporated by reference as a part of the specification. The high molecular weight hydrocarbon-substituted acids having at least about 50 aliphatic carbon atoms in the substituent, particularly those having from about 60 to about 5,000 aliphatic carbon atoms, are especially desirable for use herein. Likewise useful are the anhydrides and other acid-producing derivatives of the acids, such as are described in U.S. Pat. No. 3,219,666.
A particularly preferred class of high molecular weight carboxy compounds are the hydrocarbon-substituted succinic acids and anhydrides having from about 50, usually less than 5,000, aliphatic carbon atoms such as are described in U.S. Pat. No. 3,219,666. They include, for example, polyisobutenyl (760 molecular weight) succinic acid, polyisobutenyl (molecular weight of 900) succinic acid, polypropenyl (average molecular weight of 700) succinic anhydride, polyisobutyl (average molecular weight of 1,500) succinic acid. Other acids and derivatives are exemplified by those obtained by the reaction of a halogenated hydrocarbon such as chlorinated polyisobutene (e.g., having molecular weight of 1,000) with an alpha, beta-unsaturated acid-producing compound such as acrylic acid, methacrylic acid, or methyl acrylate. They are described in U.S. Pat. No. 3,374,174, the disclosure of which is also herein incorporated by reference as part of the present specification.
The process by which the compositions of this invention are prepared may be conducted at any temperature such as 25°C up to the decomposition temperature of the process mixture. In some instances, a solvent such as benzene, toluene, naphtha, or mineral oil is desirable in the process. The preferred mixing temperature is at least about 50°C and below 250°C. The usual temperature is from about 50°C to about 150°C.
The amount of the high molecular weight carboxylic acid or anhydride used to treat the complex may be such as to be equivalent to the basicity (as measured by base numbers) of the basic metal complex. Often it is such as to be equivalent to 90 percent or less of the basicity of the complex; usually it is such as to be equivalent to 40 percent or less of basicity. In terms of weight proportions, as little as 0.1 percent, usually from 1 to 10 percent and preferably from 3 to 5 percent (by weight of the complex) of the acid or derivative thereof is useful to accomplish the treatment.
In lieu of high molecular weight carboxylic acids or anhydrides, the corresponding amine salts, ammonium salts, imides, amides, and esters of the acids may be used in certain instances. In such instances, the proportions of the salts, amides, imides or esters to the complex are critical. Ordinarily, the proportion of such derivative should be such that it is equivalent to at least 1 but no more than 25 percent, more often from 5 to 10 percent, of the basicity of the complex. Outside such range, the derivative is not effective as treatment of the complex for the purposes of this invention. Derivatives of the high molecular weight acids are described in U.S. Pat. Nos. 3,219,666, 3,374,174 and 3,381,022, the disclosures of which are herein incorporated as part of the present specification. As specific examples, the acylated nitrogen compositions disclosed in U.S. Pat. No. 3,219,666, particularly those derived from the high molecular weight succinic acids and ammonia, monoamines and alkylene polyamines and the esters disclosed in U.S. Pat. No. 3,381,022 are especially useful in the present invention. Where an acylated nitrogen composition or ester is used as a high molecular weight carboxylic acid derivative in the process of the invention, the temperature of the treatment should be at least about 100°C, usually up to about 250°C.
The following examples are illustrative of the processes of this invention.
EXAMPLE 1
A mineral oil solution of a basic, carbonated calcium complex is prepared by carbonating a mixture of an alkylated benzene sulfonic acid (molecular weight of 470) an alkylated calcium phenate, a mixture of lower alcohols (methanol, butanol, and pentanol) and excess lime (5.6 equivalents per equivalent of the acid). The solution has a sulfur content of 1.7 percent, a calcium content of 12.6 percent and a base number of 336. To 950 grams of the solution, there is added 50 grams of a polyisobutene (molecular weight of 1000)-substituted succinic anhydride (having a saponification number of 100) at 25°C. The mixture is stirred, heated to 150°C, held at that temperature for 0.5 hour, and filtered. The filtrate has a base number of 315 and contains 35.4 percent of mineral oil.
EXAMPLE 2
To 950 grams of a solution of a basic, carbonated, calcium salt of an alkylated benzene sulfonic acid (average molecular weight - 425) in mineral oil (base number -- 406, calcium -- 15.2 percent and sulfur -- 1.4 percent) there is added 50 grams of the polyisobutenyl succinic anhydride of Example 1 at 57°C. The mixture is stirred for 0.65 hour at 55°-57°C, then at 152°-153°C for 0.5 hour and filtered at 150°C. The filtrate has a base number of 387 and contains 43.7 percent of mineral oil.
EXAMPLE 3
A mixture comprising 753 parts (by weight) of mineral oil, 1440 parts of xylene, 84 parts of a mixture of a commercial fatty acid mixture (acid number of 200), 590 parts of an alkylated benzene sulfonic acid (average molecular weight - 500), and 263 parts of magnesium oxide is heated to 60°C. Methanol (360 parts) and water (180 parts) are added. The mixture is carbonated at 65°C-98°C while methanol and water are being removed by azeotropic distillation. Additional water (180 parts) is then added and carbonation is continued at 87°-90°C for three and a half hours. Thereafter, the reaction mixture is heated to 160°C at 20 mm (Hg) and filtered at 160°C to give a basic, carbonated magnesium sulfonate-carboxylate complex (78.1 percent yield) containing 7.69 percent of magnesium and 1.67 percent of sulfur and having a base number of 336. To 950 parts of the above basic, carbonated magnesium complex, there is added 50 parts of the polyisobutenyl succinic anhydride of Example 1 and the mixture is heated to 150°C for one-half hour and then filtered to give a composition having a base number of 315.
EXAMPLE 4
To 66.7 grams of a mineral oil solution of a basic, carbonated, calcium sulfonate complex derived from an alkylbenzene sulfonic acid (average molecular weight -- 500) (the complex containing 15.5 percent of calcium, 1.56 percent of sulfur, and base number of 410), 33,3 grams of a mineral oil solution of a basic, carbonated calcium sulfonate complex derived from an alkylbenzene sulfonic acid (average molecular weight -- 500) (the complex containing 4.7 percent of calcium 2.63 percent of sulfur and base number of 84.5), 0.15 gram of a 50 percent kerosene solution of a polysiloxane foam-inhibitor and 0.25 gram of a 10 percent kerosene solution of a second polysiloxane foam-inhibitor, there is added 3 grams of a polyisobutenyl (molecular weight of 1000)-succinic anhydride (having a saponification number of 100). The mixture is stirred at 60°-70°C.
EXAMPLE 5
To 950 grams of a mineral oil solution of a basic, carbonated calcium sulfonate complex of an alkylbenzene sulfonic acid (average molecular weight -- 440) (the complex containing 13.55 percent calcium, 1.81 percent sulfur and base number of 345), there is added 50 grams of a high molecular weight polyisobutenyl-substituted mono-carboxylic acid (having an acid number of 48 and prepared by heating a chlorinated polyisobutene having an average molecular weight of 1000 and a chlorine content of 4.3 percent with acrylic acid). The mixture is heated at 150°-160°C while a stream of nitrogen is passed through it at 2 cubic feet per hour. The material is then filtered to give a composition having a base number of 318.
EXAMPLE 6
A mixture comprising 906 grams (1.5 equivalents) of an oil solution of an alkylbenzene sulfonic acid (average molecular weight - 460-480), 564 grams of mineral oil, 600 grams of toluene, 95.7 grams of magnesium oxide (4.4 equivalents), and 120 grams of water is carbonated at a temperature of about 78°-85°C for about 7 hours at a rate of about 3 cubic feet of carbon dioxide per hour. The carbonated product is stripped by heating to 165°C at a pressure of 20 mm (Hg) and filtered. The filtrate is an oil solution of a basic, carbonated magnesium sulfonate complex having a metal ratio of 3.1 and containing 15.27 percent of magnesium sulfate ash, 2.66 percent of sulfur and a base number of 98. To 95 grams of this complex there is added 5 grams of the polyisobutenyl succinic anhydride of Example 1 and the mixture is stirred at 150°C and filtered.
EXAMPLE 7
To 950 grams of a solution of a basic, carbonated calcium sulfonate complex derived from mahogany sulfonic acid in mineral oil (containing 12.0 percent calcium, 1.78 percent sulfur and having a base number of 300), there is added 83 grams of a 60 percent mineral oil solution of an ammonium salt of a polyisobutenyl succinic acid containing 0.66 percent nitrogen. The mixture is heated at 160°C for 0.5 hour. The residue is then filtered. The filtrate contains 24 percent oil.
EXAMPLE 8
A solution of a basic, carbonated calcium complex of a mahogany sulfonic acid in mineral oil, containing 15.5 percent calcium, 1.35 percent sulfur and having a base number of 400 is mixed with 2 percent by weight of a mono-methyl ester of the polyisobutenyl succinic acid of the anhydride of Example 1 at 100°-120°C until a homogeneous mass is obtained.
EXAMPLE 9
To 936 grams of a solution of a basic, carbonated calcium complex of an alkylbenzene sulfonic acid (average molecular weight - 440) in mineral oil, containing 13.55 percent calcium, 1.81 percent sulfur and having a base number of 345 there is added 64 grams of a 78 percent solution of a polyisobutenyl succinimide in mineral oil (containing 1 percent nitrogen). The mixture is heated at 150°-160°C for 1 hour and then filtered. The filtrate has a base number of 328, and contains 22.4 percent mineral oil.
EXAMPLE 10
A mixture of 1,400 grams (10 equivalents of basic metal) of a solution of a basic, carbonated calcium complex of a petrosulfonic acid (average molecular weight -- 450) in mineral oil (containing 15.5 percent calcium, 1.35 percent sulfur and a base number of 400) and 1,650 grams (3 equivalents) of a polyisobutenyl succinic acid, having an acid number of 102 is prepared and heated at 150°C until a homogeneous mass is obtained. The material is then filtered.
EXAMPLE 11
A mixture of 2,576 grams of mineral oil, 240 grams (1.85 equivalents) of octyl alcohol, 740 grams (20.0 equivalents) of calcium hydroxide, 2304 grams (8 equivalents) of oleic acid, and 392 grams (12.3 equivalents) of methyl alcohol is heated with stirring to a temperature about 50°C. in about 0.5 hour. This mixture then is treated with CO 2 (3 cubic feet per hour) at 50°-60°C. for a period of about 3.5 hours. The resulting mixture is heated to 150°C. and filtered. The filtrate is a basic calcium oleate complex having the following analyses:
Sulfate ash (percent) 24.1
Metal ratio 2.5
Neut. No. (acidic) 2.0
The basic, carbonated calcium complex of Example 1 is replaced by this basic calcium oleate complex and the general procedure described in Example 1 for the treatment with polyisobutene-substituted succinic anhydride is followed. The product is a composition of this invention.
The compositions of this process can be employed as additives in lubricants intended for use in the automobile crankcases, transmissions, gears, chassis, torque converters, as well as in other automotive equipment, industrial machinery, construction industry equipment, railroad locomotives, and ships. Other suitable uses for these compositions are as additives in asphalt emulsions, and insecticidal compositions; as stabilizing agents for plasticizers and plastics; as additives in paints, rust-inhibiting compositions, slushing oils, cutting oils, flushing oils, and tanning compositions; as emulsifying agents, antiseptic cleaning compositions, fat-splitting compositions, and flotation agents; and as improving agents in fuels such as gasoline, fuel oils, gas oil, etc.
When used as lubricating additives the compositions are usually present at concentrations ranging from about 0.1 to about 20 percent by weight of the lubricating composition. More particularly, the optimum concentration in crankcase lubricants for gasoline engines is usually from about 0.1 to about 10 percent by weight, and the optimum concentration in crankcase lubricants for diesel engines is usually from about 1 to about 20 percent by weight. For use in fuels, the concentration may be as little as 0.0001 to about 2 percent by weight.
The additives can be effectively employed in a variety of lubricating compositions based on diverse oils of lubricating viscosity such as a natural or synthetic lubricating oil, or suitable mixtures thereof. As indicated previously, the lubricating compositions contemplated include principally crankcase lubricating oils for spark-ignited and compression-ignited internal combustion engines including automobile and truck engines, two-cycle engine lubricants, aviation piston engines, marine and railroad diesel engines, and the like. However, automatic transmission fluids, trans-axle lubricants, gear lubricants, metal-working lubricants, hydraulic fluids, and other lubricating oil and grease compositions can benefit from the incorporation of the present additives.
Natural oils include animal oils and vegetable oils (e.g., castor oil, lard oil) as well as solvent-refined or acid-refined mineral lubricating oils of the paraffinic, naphthenic, or mixed paraffinic-naphthenic types. Oils of lubricating viscosity derived from coal or shale are also useful base oils. Synthetic lubricating oils include hydrocarbon oils and halo-substituted hydrocarbon oils such as polymerized and interpolymerized olefins (e.g., polybutylenes, polypropylenes, propylene-isobutylene copolymers, chlorinated polybutylenes, etc.); alkyl benzenes (e.g., dodecylbenzenes, tetradecylbenzenes, dinonylbenzenes, di-(2-ethylhexyl)benzenes, etc.); polyphenyls (e.g., biphenyls, terphenyls, etc.); and the like. Alkylene oxide polymers and interpolymers and derivatives thereof where the terminal hydroxyl groups have been modified by esterification, etherification, etc., constitute another class of known synthetic lubricating oils. These are exemplified by the oils prepared through polymerization of ethylene oxide or propylene oxide, the alkyl and aryl ethers of these polyoxyalkylene polymers (e.g., methylpolyisopropylene glycol ether having an average molecular weight of 1,000), diphenyl ether of polyethylene glycol having a molecular weight of 500-1,000, diethyl ether of polypropylene glycol having a molecular weight of 1000-1,500, etc.) or mono- and polycarboxylic esters thereof, for example, the acetic acid esters, mixed C 3 -C 8 fatty acid esters, or the C 13 acid diester of tetraethylene glycol. Another suitable class of synthetic lubricating oils comprises the esters of dicarboxylic acids (e.g., phthalic acid, succinic acid, maleic acid, azelaic acid, suberic acid, sebacic acid, fumaric acid, adipic acid, linoleic acid dimer, etc.) with a variety of alcohols (e.g., butyl alcohol, hexyl alcohol, dodecyl alcohol, 2-ethylhexyl alcohol, pentaerythritol, etc.). Specific examples of these esters include dibutyl adipate, di-(2-ethylhexyl)sebacate, di-n-hexyl fumarate, dioctyl sebacate, diisooctyl azelate, diisodecyl azelate, dioctyl phthalate, didecyl phthalate, dieicosyl sebacate, the 2-ethylhexyl diester of linoleic acid dimer, the complex ester formed by reacting one mole of sebacic acid with 2 moles of tetraethylene glycol and 2 moles of 2-ethylhexanoic acid, and the like. Silicon-based oils such as the polyalkyl-, and polyaryl-, polyalkoxy-, or polyaryloxy-siloxane oils and silicate oils comprise another useful class of synthetic lubricants (e.g., tetraethyl-silicate, tetraisopropyl-silicate, tetra-(2-ethylhexyl)-silicate, tetra-(4-methyl-2-tetraethyl)-silicate, tetra-(p-tertbutylphenyl)-silicate, hexyl-(4-methyl-2-pentoxy)-disiloxane, poly(methyl)-siloxanes, poly(methylphenyl)-siloxanes, etc.). Other synthetic lubricating oils include liquid esters of phosphorus-containing acids (e.g., tricresyl phosphate, trioctyl phosphate, diethyl ester of decane phosphonic acid, etc.), polymeric tetrahydrofurans, and the like.
As noted above, other additives may be present in the fuels and lubricants in which the composition of this invention is present. Such other additives include, for instance, supplemental detergents of the ash-containing or ashless type, viscosity improving agents, pour point depressing agents, supplemental anti-foam agents, extreme pressure agents, rust-inhibiting agents, oxidation inhibiting agents, friction improving agents, and corrosion inhibiting agents.
The supplemental ash-containing detergents are exemplified by oil soluble neutral and basic salts of organic phosphorus acids characterized by at least one direct carbon-to-phosphorus linkage such as those prepared by the treatment of an olefin polymer (e.g., polyisobutene having a molecular weight of 1,000) with a phosphorizing agent such as phosphorus trichloride, phosphorus heptasulfide, phosphorus pentasulfide, phosphorus trichloride and sulfur, white phosphorus and a sulfur halide, or phosphorothioic chloride. The most commonly used salts of such acids are those of sodium, potassium, lithium, calcium, magnesium, strontium, and barium. The ashless detergents include acylated amines such as are described in U.S. Pat. Nos. 3,172,892; 3,219,666; and 3,272,546.
Extreme pressure agents and corrosion-inhibiting and oxidation-inhibiting agents are exemplified by chlorinated aliphatic hydrocarbons such as chlorinated wax; organic sulfides and polysulfides such as benzyl disulfide, bis(chlorobenzyl) disulfide, dibutyl tetrasulfide; sulfurized sperm oil, sulfurized methyl ester of oleic acid, sulfurized alkylphenol, sulfurized dipentene, and sulfurized terpene; phosphosulfurized hydrocarbons such as the reaction product of a phosphorus sulfide with turpentine; phosphorus esters including principally dihydrocarbon and trihydrocarbon phosphites such as dibutyl phosphite, diheptyl phosphite, dicyclohexyl phosphite, pentylphenyl phosphite, metal thiocarbamates such as zinc dioctyldithiocarbamates; Group II metal phosphorodithioates such as zinc dicyclohexylphosphorodithioate, zinc dioctylphosphorodithioate, cadmium dinonylphosphorodithioate and the zinc salt of a phosphorodithioic acid produced by the reaction of phosphorus pentasulfide with a 65:35 mole percent mixture of isobutyl alcohol and primary amyl alcohol.
Examples of the anti-foam agent include poly(alkyl methacrylate), the condensation products of an alkylphenol with formaldehyde and an amine, fluorinated hydrocarbon polymers, and the polymeric alkyl- and aralkyl siloxanes.
The following examples are illustrative of the lubricating compositions of this invention: (All percentages are by weight.)
EXAMPLE A
SAE 30 mineral lubricating oil containing 20.2 percent of the composition of Example 1.
EXAMPLE B
SAE 30 mineral lubricating oil containing 17.1 percent of the composition of Example 2.
EXAMPLE C
SAE 30 mineral lubricating oil containing 20.4 percent of the composition of EXample 3.
EXAMPLE D
SAE 30 mineral lubricating oil plus 2 percent of the composition of Example 4.
EXAMPLE E
SAE 20 mineral lubricating oil containing 15 percent of the composition of Example 11.
Table I below shows the oil-solubility characteristics (in mineral oil) of the compositions of this invention (Test Samples I, III, V, and VII) and the complexes (Test Samples II, IV, VI and VIII) from which such compositions are derived. A comparison of the results establishes the effectiveness of the high molecular weight carboxylic acids or derivatives to improve the oil-solubility of the metal complexes. Test Sample IX is included to show the ineffectiveness of a preformed metal salt of the high molecular weight carboxylic acid as a treatment of the complex.
TABLE I
Test Sample Composition Concentration in Mineral Lubricating Oil (by wt.) 50% 10% 1% I Example 1 C C C II The complex from which Example 1 is derived H H M III Example 2 C C C IV The complex from which Example 2 is derived C Z,M S V Example 3 C C C VI The complex from which Example 3 is derived H H H VII Composition prepared by mixing at 160°C a basic carbonated calcium sulfonate complex (90 parts by wt.) (having a base number of 343 and 1.8 percent sulfur) and the polyisobutene substituted succinic anhydride of Example 1 (10 parts) C C C VIII The complex of VII above C H S IX Same as VII above except for the replacement of the anhydride with the calcium salt of the corresponding succinic acid C M L C=clear Z=haze M=medium sediment S=slight haze L=light sediment H=heavy sediment
Table II shows the low foaming tendencies of the compositions of this invention by a test procedure which consists of three "sequences", each sequence consisting of (a) air-blowing a mineral lubricating oil sample containing 2 percent by weight of an additive so as to generate some foam and measuring the amount of foam (in milliliters) immediately after the air-blowing and (b) repeating step (a) after the oil sample has been in storage for two weeks. Sequence (1) is carried out at room temperature and the storage temperature is room temperature. Sequence (2) is carried out at 200°F on a fresh sample; the storage temperature is 100°F. Sequence (3) is carried out at room temperature on the sample which has been tested in Sequence (2).
The numerical results reported in Table II below represent the volume of foam in milliliters as measured during the test. The volume of foam generated in a sample containing a composition of this invention is compared with that generated in a sample containing the complex from which the composition is prepared.
TABLE II
Example 4 Complex from which Example 4 is prepared Sequence (1) Step (a) 0 0 Step (b) 0 460 Sequence (2) Step (a) 10 25 Step (b) 130 260 Sequence (3) Step (a) 0 20 Step (b) 20 220
The effectiveness of the lubricants containing compositions of this invention is shown by the Panel Coker Test.
In this test, a 350 gram sample of the oil to be tested is placed in a coker reservoir having therein a splash mechanism, both reservoir and sample being at ambient temperatures, and a 1.5 × 3.5 × 0.25 inches aluminum panel is suspended above the oil in such a manner as to hermetically seal the reservoir. The oil reservoir temperature and the panel temperature are maintained at 240°-255°F and 570°-590°F, respectively, and the splash mechanism is operated for 13.5 minutes whereby the sample is splashed upon the sanded surface of the panel. The splash mechanism is then stopped and the panel is allowed to bake for 1.5 minutes. The above cycle is repeated for a total of 4 hours at the end of which time the coker test mechanism is allowed to cool. The aluminum panel is then removed, washed with naphtha and inspected. The thermal stability of the oil sample being tested is measured by the panel inspection and is rated on the basis of the deposits which have accumulated on the aluminum panel. The results of the rating are indicated on a scale of 10-0 (10 being indicative of complete absence of any such deposits and 0 being indicative of complete coverage of deposits on the panel).
The results of the Panel Coker Test are shown in Table III below. Samples (1) and (3) illustrate lubricants of Examples A and B above of the present invention whereas Samples (2) and (4) illustrate lubricants containing the metal complexes (referred to as A' and B') from which the additives of Examples A and B are derived, respectively. EAch test sample contains sufficient additive to give a base number of 65.
TABLE III
Rating (1) Example A 9 (2) Lubricant containing A' 4 (3) Example B 8 (4) Lubricant containing B' 6
Basic metal complexes are well-known in the art. They are of utility as lubricant additives, paint-dryers, stabilizers for plastics, emulsifiers, rust preventives and the like. They are especially valuable because of their detergent or dispersant properties and their ability to neutralize undesirable acidic bodies formed in, e.g., crankcase lubricants under service conditions. For this reason they are one of the most commonly used lubricant additives. The incorporation of basic complexes into lubricating compositions in some cases gives rise to problems. Among these problems is the greater tendency of lubricating compositions containing detergent additives to foam. Another problem is that the lubricant compositions tend to form haze on standing.
It is, therefore, a principal object of this invention to provide basic metal complexes having a reduced tendency to cause foam in lubricants.
A further object is to provide basic metal complexes having improved oil-solubility.
Another object of this invention is to provide lubricating compositions containing an improved basic metal complex.
Another object is to provide a method of treating basic metal complexes to improve the foam and solubility properties thereof.
Further objects of this invention will become apparent from the following description thereof.
These objects are attained by a composition prepared by mixing (A) a basic metal complex selected from the class consisting of sulfonate, sulfonate-carboxylate and carboxylate complexes with up to an amount equivalent to the total basicity thereof of (B) high molecular weight aliphatic carboxylic acid or anhydride wherein there are at least about 25 aliphatic carbon atoms per carboxy group in (B) at a temperature of from about 25°C to the decomposition temperature of the process mass.
As used in the present specification and claims, the term "complex" refers to basic metal salts which contain metal in an amount in excess of that present in a neutral or normal metal salt. The "metal ratio" characterizing a complex is thus the ratio of the total equivalents of metal to the equivalents of metal in the form of neutral or normal metal. The "base number" of a complex is the number of milligrams of KOH to which one gram of the complex is equivalent as measured by titration.
The metal of the complexes may be a Group I or Group II metal such as sodium, potassium, lithium, magnesium, strontium, barium, or calcium. An alkaline earth metal, especially calcium, barium, or magnesium is preferred.
Basic metal complexes are known in the art. Those which are contemplated herein include complexes derived from oil-soluble sulfonic acids, oil-soluble carboxylic acids, and mixtures thereof, such as are described in U.S. Pat. Nos. 2,501,731; 2,616,904; 2,616,905; 2,616,906; 2,616,911; 2,616,924; 2,616,925; 2,617,049; 2,777,874; 3,027,325; 3,256,186; 3,282,835; 3,384,585; 3,373,108; 3,365,396; 3,342,733; 3,320,162; 3,312,618; and 3,318,809. For purposes of illustration, the disclosures of the above patents are hereby incorporated in the present specification insofar as the complexes useful in this invention are described.
As an example of a particularly convenient process for the preparation of the complexes used, an oil-soluble sulfonic acid, such as a synthetically prepared didodecylbenzene sulfonic acid, is mixed with an excess of lime (e.g., 10 equivalents per equivalent of the acid) and a promoter such as methanol, heptylphenol, or mixture thereof, and a solvent such as mineral oil, at 50°C-150°C and the process mass is then carbonated until a homogeneous mass is obtained. Complexes of sulfonic acids, carboxylic acids, and mixtures thereof are obtainable by processes such as are described in U.S. Pat. No. 3,312,618. Another example is the preparation of a magnesium sulfonate complex by carbonating a mixture of a sulfonic acid or normal magnesium salt thereof, an excess of magnesium oxide, water, and preferably also an alcohol such as methanol.
The carboxylic acids useful for preparing sulfonatecarboxylate complexes, and carboxylate complexes, i.e., those obtainable from processes such as the above wherein a mixture of sulfonic acid and carboxylic acid or a carboxylic acid alone is used in lieu of the sulfonic acid, are oil-soluble acids and include primarily fatty acids which have at least about 12 aliphatic carbon atoms and not more than about 24 aliphatic carbon atoms. Examples of these acids include: palmitic, stearic, myristic, oleic, linoleic, dodecanoic, behenic, etc. Cyclic carboxylic acids may also be employed. These include aromatic and cyclo-aliphatic acids. The aromatic acids are those containing a benzenoid structure (i.e., benzene, naphthalene, etc.) and an oil-solubilizing radical or radicals having a total of at least about 15 to 18 carbon atoms, preferably from about 15 to about 200 carbon atoms. Examples of the aromatic acids include: stearyl-benzoic acids, phenyl stearic acid, mono- or polywax-substituted benzoic or naphthoic acids wherein the wax group consists of at least about 18 carbon atoms, cetyl hydroxybenzoic acids, etc. The cyclo-aliphatic acids contemplated have at least about 12, usually up to about 30 carbon atoms. Examples of such acids are petroleum naphthenic acids, cetyl cyclohexane carboxylic acids, di-lauryl decahydronaphthalene carboxylic acids, di-octyl cyclopentane carboxylic acids, etc. The thiocarboxylic acid analogs of the above acids, wherein one or both of the oxygen atoms of the carboxyl group are replaced by sulfur, are also contemplated.
The ratio of the sulfonic acid to the carboxylic acid in mixtures is at least 1:1 (on a chemical equivalent basis) and is usually less than 5:1, preferably from 1:1 to 2:1.
In general, complexes having metal ratios from 1.1 to about 30 are contemplated for use in the present invention. Those having metal ratios ranging from 2 to 20 are preferred.
An important aspect of the present invention is the treatment of a complex, after it is formed, with a high molecular weight carboxylic acid or anhydride or an acid-producing derivative thereof. By "high molecular weight carboxylic acid" is meant an aliphatic acid wherein there is an average of at least about 25 aliphatic carbon atoms per carboxy radical. Such acids are exemplified by alkanoic and alkenoic acids as well as polar-substituted alkanoic or alkenoic acids. They may be either acyclic or cyclic and may contain aryl substituents. The polar substituents may be chloro, bromo, iodo, ether, nitro, or the like. The acids may contain one or more carboxy radicals, and may thus be dicarboxy, tri-carboxy, or tetracarboxy acids such as substituted succinic acids, maleic acids, malonic acids, etc. Examples of preferred high molecular weight carboxy acids are those described in U.S. Pat. No. 3,219,666, the disclosure of which, particularly that at column 6, line 47 to column 7, line 55, is hereby incorporated by reference as a part of the specification. The high molecular weight hydrocarbon-substituted acids having at least about 50 aliphatic carbon atoms in the substituent, particularly those having from about 60 to about 5,000 aliphatic carbon atoms, are especially desirable for use herein. Likewise useful are the anhydrides and other acid-producing derivatives of the acids, such as are described in U.S. Pat. No. 3,219,666.
A particularly preferred class of high molecular weight carboxy compounds are the hydrocarbon-substituted succinic acids and anhydrides having from about 50, usually less than 5,000, aliphatic carbon atoms such as are described in U.S. Pat. No. 3,219,666. They include, for example, polyisobutenyl (760 molecular weight) succinic acid, polyisobutenyl (molecular weight of 900) succinic acid, polypropenyl (average molecular weight of 700) succinic anhydride, polyisobutyl (average molecular weight of 1,500) succinic acid. Other acids and derivatives are exemplified by those obtained by the reaction of a halogenated hydrocarbon such as chlorinated polyisobutene (e.g., having molecular weight of 1,000) with an alpha, beta-unsaturated acid-producing compound such as acrylic acid, methacrylic acid, or methyl acrylate. They are described in U.S. Pat. No. 3,374,174, the disclosure of which is also herein incorporated by reference as part of the present specification.
The process by which the compositions of this invention are prepared may be conducted at any temperature such as 25°C up to the decomposition temperature of the process mixture. In some instances, a solvent such as benzene, toluene, naphtha, or mineral oil is desirable in the process. The preferred mixing temperature is at least about 50°C and below 250°C. The usual temperature is from about 50°C to about 150°C.
The amount of the high molecular weight carboxylic acid or anhydride used to treat the complex may be such as to be equivalent to the basicity (as measured by base numbers) of the basic metal complex. Often it is such as to be equivalent to 90 percent or less of the basicity of the complex; usually it is such as to be equivalent to 40 percent or less of basicity. In terms of weight proportions, as little as 0.1 percent, usually from 1 to 10 percent and preferably from 3 to 5 percent (by weight of the complex) of the acid or derivative thereof is useful to accomplish the treatment.
In lieu of high molecular weight carboxylic acids or anhydrides, the corresponding amine salts, ammonium salts, imides, amides, and esters of the acids may be used in certain instances. In such instances, the proportions of the salts, amides, imides or esters to the complex are critical. Ordinarily, the proportion of such derivative should be such that it is equivalent to at least 1 but no more than 25 percent, more often from 5 to 10 percent, of the basicity of the complex. Outside such range, the derivative is not effective as treatment of the complex for the purposes of this invention. Derivatives of the high molecular weight acids are described in U.S. Pat. Nos. 3,219,666, 3,374,174 and 3,381,022, the disclosures of which are herein incorporated as part of the present specification. As specific examples, the acylated nitrogen compositions disclosed in U.S. Pat. No. 3,219,666, particularly those derived from the high molecular weight succinic acids and ammonia, monoamines and alkylene polyamines and the esters disclosed in U.S. Pat. No. 3,381,022 are especially useful in the present invention. Where an acylated nitrogen composition or ester is used as a high molecular weight carboxylic acid derivative in the process of the invention, the temperature of the treatment should be at least about 100°C, usually up to about 250°C.
The following examples are illustrative of the processes of this invention.
EXAMPLE 1
A mineral oil solution of a basic, carbonated calcium complex is prepared by carbonating a mixture of an alkylated benzene sulfonic acid (molecular weight of 470) an alkylated calcium phenate, a mixture of lower alcohols (methanol, butanol, and pentanol) and excess lime (5.6 equivalents per equivalent of the acid). The solution has a sulfur content of 1.7 percent, a calcium content of 12.6 percent and a base number of 336. To 950 grams of the solution, there is added 50 grams of a polyisobutene (molecular weight of 1000)-substituted succinic anhydride (having a saponification number of 100) at 25°C. The mixture is stirred, heated to 150°C, held at that temperature for 0.5 hour, and filtered. The filtrate has a base number of 315 and contains 35.4 percent of mineral oil.
EXAMPLE 2
To 950 grams of a solution of a basic, carbonated, calcium salt of an alkylated benzene sulfonic acid (average molecular weight - 425) in mineral oil (base number -- 406, calcium -- 15.2 percent and sulfur -- 1.4 percent) there is added 50 grams of the polyisobutenyl succinic anhydride of Example 1 at 57°C. The mixture is stirred for 0.65 hour at 55°-57°C, then at 152°-153°C for 0.5 hour and filtered at 150°C. The filtrate has a base number of 387 and contains 43.7 percent of mineral oil.
EXAMPLE 3
A mixture comprising 753 parts (by weight) of mineral oil, 1440 parts of xylene, 84 parts of a mixture of a commercial fatty acid mixture (acid number of 200), 590 parts of an alkylated benzene sulfonic acid (average molecular weight - 500), and 263 parts of magnesium oxide is heated to 60°C. Methanol (360 parts) and water (180 parts) are added. The mixture is carbonated at 65°C-98°C while methanol and water are being removed by azeotropic distillation. Additional water (180 parts) is then added and carbonation is continued at 87°-90°C for three and a half hours. Thereafter, the reaction mixture is heated to 160°C at 20 mm (Hg) and filtered at 160°C to give a basic, carbonated magnesium sulfonate-carboxylate complex (78.1 percent yield) containing 7.69 percent of magnesium and 1.67 percent of sulfur and having a base number of 336. To 950 parts of the above basic, carbonated magnesium complex, there is added 50 parts of the polyisobutenyl succinic anhydride of Example 1 and the mixture is heated to 150°C for one-half hour and then filtered to give a composition having a base number of 315.
EXAMPLE 4
To 66.7 grams of a mineral oil solution of a basic, carbonated, calcium sulfonate complex derived from an alkylbenzene sulfonic acid (average molecular weight -- 500) (the complex containing 15.5 percent of calcium, 1.56 percent of sulfur, and base number of 410), 33,3 grams of a mineral oil solution of a basic, carbonated calcium sulfonate complex derived from an alkylbenzene sulfonic acid (average molecular weight -- 500) (the complex containing 4.7 percent of calcium 2.63 percent of sulfur and base number of 84.5), 0.15 gram of a 50 percent kerosene solution of a polysiloxane foam-inhibitor and 0.25 gram of a 10 percent kerosene solution of a second polysiloxane foam-inhibitor, there is added 3 grams of a polyisobutenyl (molecular weight of 1000)-succinic anhydride (having a saponification number of 100). The mixture is stirred at 60°-70°C.
EXAMPLE 5
To 950 grams of a mineral oil solution of a basic, carbonated calcium sulfonate complex of an alkylbenzene sulfonic acid (average molecular weight -- 440) (the complex containing 13.55 percent calcium, 1.81 percent sulfur and base number of 345), there is added 50 grams of a high molecular weight polyisobutenyl-substituted mono-carboxylic acid (having an acid number of 48 and prepared by heating a chlorinated polyisobutene having an average molecular weight of 1000 and a chlorine content of 4.3 percent with acrylic acid). The mixture is heated at 150°-160°C while a stream of nitrogen is passed through it at 2 cubic feet per hour. The material is then filtered to give a composition having a base number of 318.
EXAMPLE 6
A mixture comprising 906 grams (1.5 equivalents) of an oil solution of an alkylbenzene sulfonic acid (average molecular weight - 460-480), 564 grams of mineral oil, 600 grams of toluene, 95.7 grams of magnesium oxide (4.4 equivalents), and 120 grams of water is carbonated at a temperature of about 78°-85°C for about 7 hours at a rate of about 3 cubic feet of carbon dioxide per hour. The carbonated product is stripped by heating to 165°C at a pressure of 20 mm (Hg) and filtered. The filtrate is an oil solution of a basic, carbonated magnesium sulfonate complex having a metal ratio of 3.1 and containing 15.27 percent of magnesium sulfate ash, 2.66 percent of sulfur and a base number of 98. To 95 grams of this complex there is added 5 grams of the polyisobutenyl succinic anhydride of Example 1 and the mixture is stirred at 150°C and filtered.
EXAMPLE 7
To 950 grams of a solution of a basic, carbonated calcium sulfonate complex derived from mahogany sulfonic acid in mineral oil (containing 12.0 percent calcium, 1.78 percent sulfur and having a base number of 300), there is added 83 grams of a 60 percent mineral oil solution of an ammonium salt of a polyisobutenyl succinic acid containing 0.66 percent nitrogen. The mixture is heated at 160°C for 0.5 hour. The residue is then filtered. The filtrate contains 24 percent oil.
EXAMPLE 8
A solution of a basic, carbonated calcium complex of a mahogany sulfonic acid in mineral oil, containing 15.5 percent calcium, 1.35 percent sulfur and having a base number of 400 is mixed with 2 percent by weight of a mono-methyl ester of the polyisobutenyl succinic acid of the anhydride of Example 1 at 100°-120°C until a homogeneous mass is obtained.
EXAMPLE 9
To 936 grams of a solution of a basic, carbonated calcium complex of an alkylbenzene sulfonic acid (average molecular weight - 440) in mineral oil, containing 13.55 percent calcium, 1.81 percent sulfur and having a base number of 345 there is added 64 grams of a 78 percent solution of a polyisobutenyl succinimide in mineral oil (containing 1 percent nitrogen). The mixture is heated at 150°-160°C for 1 hour and then filtered. The filtrate has a base number of 328, and contains 22.4 percent mineral oil.
EXAMPLE 10
A mixture of 1,400 grams (10 equivalents of basic metal) of a solution of a basic, carbonated calcium complex of a petrosulfonic acid (average molecular weight -- 450) in mineral oil (containing 15.5 percent calcium, 1.35 percent sulfur and a base number of 400) and 1,650 grams (3 equivalents) of a polyisobutenyl succinic acid, having an acid number of 102 is prepared and heated at 150°C until a homogeneous mass is obtained. The material is then filtered.
EXAMPLE 11
A mixture of 2,576 grams of mineral oil, 240 grams (1.85 equivalents) of octyl alcohol, 740 grams (20.0 equivalents) of calcium hydroxide, 2304 grams (8 equivalents) of oleic acid, and 392 grams (12.3 equivalents) of methyl alcohol is heated with stirring to a temperature about 50°C. in about 0.5 hour. This mixture then is treated with CO 2 (3 cubic feet per hour) at 50°-60°C. for a period of about 3.5 hours. The resulting mixture is heated to 150°C. and filtered. The filtrate is a basic calcium oleate complex having the following analyses:
Sulfate ash (percent) 24.1
Metal ratio 2.5
Neut. No. (acidic) 2.0
The basic, carbonated calcium complex of Example 1 is replaced by this basic calcium oleate complex and the general procedure described in Example 1 for the treatment with polyisobutene-substituted succinic anhydride is followed. The product is a composition of this invention.
The compositions of this process can be employed as additives in lubricants intended for use in the automobile crankcases, transmissions, gears, chassis, torque converters, as well as in other automotive equipment, industrial machinery, construction industry equipment, railroad locomotives, and ships. Other suitable uses for these compositions are as additives in asphalt emulsions, and insecticidal compositions; as stabilizing agents for plasticizers and plastics; as additives in paints, rust-inhibiting compositions, slushing oils, cutting oils, flushing oils, and tanning compositions; as emulsifying agents, antiseptic cleaning compositions, fat-splitting compositions, and flotation agents; and as improving agents in fuels such as gasoline, fuel oils, gas oil, etc.
When used as lubricating additives the compositions are usually present at concentrations ranging from about 0.1 to about 20 percent by weight of the lubricating composition. More particularly, the optimum concentration in crankcase lubricants for gasoline engines is usually from about 0.1 to about 10 percent by weight, and the optimum concentration in crankcase lubricants for diesel engines is usually from about 1 to about 20 percent by weight. For use in fuels, the concentration may be as little as 0.0001 to about 2 percent by weight.
The additives can be effectively employed in a variety of lubricating compositions based on diverse oils of lubricating viscosity such as a natural or synthetic lubricating oil, or suitable mixtures thereof. As indicated previously, the lubricating compositions contemplated include principally crankcase lubricating oils for spark-ignited and compression-ignited internal combustion engines including automobile and truck engines, two-cycle engine lubricants, aviation piston engines, marine and railroad diesel engines, and the like. However, automatic transmission fluids, trans-axle lubricants, gear lubricants, metal-working lubricants, hydraulic fluids, and other lubricating oil and grease compositions can benefit from the incorporation of the present additives.
Natural oils include animal oils and vegetable oils (e.g., castor oil, lard oil) as well as solvent-refined or acid-refined mineral lubricating oils of the paraffinic, naphthenic, or mixed paraffinic-naphthenic types. Oils of lubricating viscosity derived from coal or shale are also useful base oils. Synthetic lubricating oils include hydrocarbon oils and halo-substituted hydrocarbon oils such as polymerized and interpolymerized olefins (e.g., polybutylenes, polypropylenes, propylene-isobutylene copolymers, chlorinated polybutylenes, etc.); alkyl benzenes (e.g., dodecylbenzenes, tetradecylbenzenes, dinonylbenzenes, di-(2-ethylhexyl)benzenes, etc.); polyphenyls (e.g., biphenyls, terphenyls, etc.); and the like. Alkylene oxide polymers and interpolymers and derivatives thereof where the terminal hydroxyl groups have been modified by esterification, etherification, etc., constitute another class of known synthetic lubricating oils. These are exemplified by the oils prepared through polymerization of ethylene oxide or propylene oxide, the alkyl and aryl ethers of these polyoxyalkylene polymers (e.g., methylpolyisopropylene glycol ether having an average molecular weight of 1,000), diphenyl ether of polyethylene glycol having a molecular weight of 500-1,000, diethyl ether of polypropylene glycol having a molecular weight of 1000-1,500, etc.) or mono- and polycarboxylic esters thereof, for example, the acetic acid esters, mixed C 3 -C 8 fatty acid esters, or the C 13 acid diester of tetraethylene glycol. Another suitable class of synthetic lubricating oils comprises the esters of dicarboxylic acids (e.g., phthalic acid, succinic acid, maleic acid, azelaic acid, suberic acid, sebacic acid, fumaric acid, adipic acid, linoleic acid dimer, etc.) with a variety of alcohols (e.g., butyl alcohol, hexyl alcohol, dodecyl alcohol, 2-ethylhexyl alcohol, pentaerythritol, etc.). Specific examples of these esters include dibutyl adipate, di-(2-ethylhexyl)sebacate, di-n-hexyl fumarate, dioctyl sebacate, diisooctyl azelate, diisodecyl azelate, dioctyl phthalate, didecyl phthalate, dieicosyl sebacate, the 2-ethylhexyl diester of linoleic acid dimer, the complex ester formed by reacting one mole of sebacic acid with 2 moles of tetraethylene glycol and 2 moles of 2-ethylhexanoic acid, and the like. Silicon-based oils such as the polyalkyl-, and polyaryl-, polyalkoxy-, or polyaryloxy-siloxane oils and silicate oils comprise another useful class of synthetic lubricants (e.g., tetraethyl-silicate, tetraisopropyl-silicate, tetra-(2-ethylhexyl)-silicate, tetra-(4-methyl-2-tetraethyl)-silicate, tetra-(p-tertbutylphenyl)-silicate, hexyl-(4-methyl-2-pentoxy)-disiloxane, poly(methyl)-siloxanes, poly(methylphenyl)-siloxanes, etc.). Other synthetic lubricating oils include liquid esters of phosphorus-containing acids (e.g., tricresyl phosphate, trioctyl phosphate, diethyl ester of decane phosphonic acid, etc.), polymeric tetrahydrofurans, and the like.
As noted above, other additives may be present in the fuels and lubricants in which the composition of this invention is present. Such other additives include, for instance, supplemental detergents of the ash-containing or ashless type, viscosity improving agents, pour point depressing agents, supplemental anti-foam agents, extreme pressure agents, rust-inhibiting agents, oxidation inhibiting agents, friction improving agents, and corrosion inhibiting agents.
The supplemental ash-containing detergents are exemplified by oil soluble neutral and basic salts of organic phosphorus acids characterized by at least one direct carbon-to-phosphorus linkage such as those prepared by the treatment of an olefin polymer (e.g., polyisobutene having a molecular weight of 1,000) with a phosphorizing agent such as phosphorus trichloride, phosphorus heptasulfide, phosphorus pentasulfide, phosphorus trichloride and sulfur, white phosphorus and a sulfur halide, or phosphorothioic chloride. The most commonly used salts of such acids are those of sodium, potassium, lithium, calcium, magnesium, strontium, and barium. The ashless detergents include acylated amines such as are described in U.S. Pat. Nos. 3,172,892; 3,219,666; and 3,272,546.
Extreme pressure agents and corrosion-inhibiting and oxidation-inhibiting agents are exemplified by chlorinated aliphatic hydrocarbons such as chlorinated wax; organic sulfides and polysulfides such as benzyl disulfide, bis(chlorobenzyl) disulfide, dibutyl tetrasulfide; sulfurized sperm oil, sulfurized methyl ester of oleic acid, sulfurized alkylphenol, sulfurized dipentene, and sulfurized terpene; phosphosulfurized hydrocarbons such as the reaction product of a phosphorus sulfide with turpentine; phosphorus esters including principally dihydrocarbon and trihydrocarbon phosphites such as dibutyl phosphite, diheptyl phosphite, dicyclohexyl phosphite, pentylphenyl phosphite, metal thiocarbamates such as zinc dioctyldithiocarbamates; Group II metal phosphorodithioates such as zinc dicyclohexylphosphorodithioate, zinc dioctylphosphorodithioate, cadmium dinonylphosphorodithioate and the zinc salt of a phosphorodithioic acid produced by the reaction of phosphorus pentasulfide with a 65:35 mole percent mixture of isobutyl alcohol and primary amyl alcohol.
Examples of the anti-foam agent include poly(alkyl methacrylate), the condensation products of an alkylphenol with formaldehyde and an amine, fluorinated hydrocarbon polymers, and the polymeric alkyl- and aralkyl siloxanes.
The following examples are illustrative of the lubricating compositions of this invention: (All percentages are by weight.)
EXAMPLE A
SAE 30 mineral lubricating oil containing 20.2 percent of the composition of Example 1.
EXAMPLE B
SAE 30 mineral lubricating oil containing 17.1 percent of the composition of Example 2.
EXAMPLE C
SAE 30 mineral lubricating oil containing 20.4 percent of the composition of EXample 3.
EXAMPLE D
SAE 30 mineral lubricating oil plus 2 percent of the composition of Example 4.
EXAMPLE E
SAE 20 mineral lubricating oil containing 15 percent of the composition of Example 11.
Table I below shows the oil-solubility characteristics (in mineral oil) of the compositions of this invention (Test Samples I, III, V, and VII) and the complexes (Test Samples II, IV, VI and VIII) from which such compositions are derived. A comparison of the results establishes the effectiveness of the high molecular weight carboxylic acids or derivatives to improve the oil-solubility of the metal complexes. Test Sample IX is included to show the ineffectiveness of a preformed metal salt of the high molecular weight carboxylic acid as a treatment of the complex.
TABLE I
Test Sample Composition Concentration in Mineral Lubricating Oil (by wt.) 50% 10% 1% I Example 1 C C C II The complex from which Example 1 is derived H H M III Example 2 C C C IV The complex from which Example 2 is derived C Z,M S V Example 3 C C C VI The complex from which Example 3 is derived H H H VII Composition prepared by mixing at 160°C a basic carbonated calcium sulfonate complex (90 parts by wt.) (having a base number of 343 and 1.8 percent sulfur) and the polyisobutene substituted succinic anhydride of Example 1 (10 parts) C C C VIII The complex of VII above C H S IX Same as VII above except for the replacement of the anhydride with the calcium salt of the corresponding succinic acid C M L C=clear Z=haze M=medium sediment S=slight haze L=light sediment H=heavy sediment
Table II shows the low foaming tendencies of the compositions of this invention by a test procedure which consists of three "sequences", each sequence consisting of (a) air-blowing a mineral lubricating oil sample containing 2 percent by weight of an additive so as to generate some foam and measuring the amount of foam (in milliliters) immediately after the air-blowing and (b) repeating step (a) after the oil sample has been in storage for two weeks. Sequence (1) is carried out at room temperature and the storage temperature is room temperature. Sequence (2) is carried out at 200°F on a fresh sample; the storage temperature is 100°F. Sequence (3) is carried out at room temperature on the sample which has been tested in Sequence (2).
The numerical results reported in Table II below represent the volume of foam in milliliters as measured during the test. The volume of foam generated in a sample containing a composition of this invention is compared with that generated in a sample containing the complex from which the composition is prepared.
TABLE II
Example 4 Complex from which Example 4 is prepared Sequence (1) Step (a) 0 0 Step (b) 0 460 Sequence (2) Step (a) 10 25 Step (b) 130 260 Sequence (3) Step (a) 0 20 Step (b) 20 220
The effectiveness of the lubricants containing compositions of this invention is shown by the Panel Coker Test.
In this test, a 350 gram sample of the oil to be tested is placed in a coker reservoir having therein a splash mechanism, both reservoir and sample being at ambient temperatures, and a 1.5 × 3.5 × 0.25 inches aluminum panel is suspended above the oil in such a manner as to hermetically seal the reservoir. The oil reservoir temperature and the panel temperature are maintained at 240°-255°F and 570°-590°F, respectively, and the splash mechanism is operated for 13.5 minutes whereby the sample is splashed upon the sanded surface of the panel. The splash mechanism is then stopped and the panel is allowed to bake for 1.5 minutes. The above cycle is repeated for a total of 4 hours at the end of which time the coker test mechanism is allowed to cool. The aluminum panel is then removed, washed with naphtha and inspected. The thermal stability of the oil sample being tested is measured by the panel inspection and is rated on the basis of the deposits which have accumulated on the aluminum panel. The results of the rating are indicated on a scale of 10-0 (10 being indicative of complete absence of any such deposits and 0 being indicative of complete coverage of deposits on the panel).
The results of the Panel Coker Test are shown in Table III below. Samples (1) and (3) illustrate lubricants of Examples A and B above of the present invention whereas Samples (2) and (4) illustrate lubricants containing the metal complexes (referred to as A' and B') from which the additives of Examples A and B are derived, respectively. EAch test sample contains sufficient additive to give a base number of 65.
TABLE III
Rating (1) Example A 9 (2) Lubricant containing A' 4 (3) Example B 8 (4) Lubricant containing B' 6