Coon, Marvin D. (Novato, CA)
Honnen, Lewis R. (Petaluma, CA)

05/256241

03/25/1975

05/24/1972

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Chevron Research Company (San Francisco, CA)

508/552

508/232, 508/558, 508/554

C10M133/54; C10M133/00; C10M1/32

252/51.5A,51.5R,51,50

3454555	OIL-SOLUBLE HALOGEN-CONTAINING POLYAMINES AND POLYETHYLENEIMINES	July 1969	Van der Voort et al.
3785789	FUEL DETERGENTS	January 1974	Honnen et al.

Gantz, Delbert E.

Metz, Andrew H.

Magdeburger, Tonkin Nelson G. F. C. J. M. D.

We claim

1. A lubricating oil composition comprising an oil of lubricating viscosity and a detergent amount of the product of a hydrocarbyl-substituted polyamine, wherein the hydrocarbyl is of from 40 to 300 carbon atoms and is an aliphatic or alicyclic branched chain hydrocarbyl radical derived from petroleum hydrocarbons or polyolefins of monomers from 2 to 6 carbon atoms, with the proviso that when the monomer is ethylene, it is copolymerized with a higher homolog and a coupling agent selected from the group consisting of C₂ -C₂₀ hydrocarbyl polycarboxylic acids anhydrides or halides thereof, hydrocarbyl polyisocyanates, and C₂ -C₂₀ hydrocarbyl dihalides.

2. A composition according to claim 1, wherein the hydrocarbyl polyamine is of the general formula: ##SPC3##

3. A composition according to claim 2, wherein the hydrocarbyl polyamine is a polyisobutenyl ethylene diamine having from 1 to 2 polyisobutenyl groups of from about 560 to about 2,000 average molecular weight.

4. A composition according to claim 2, wherein the hydrocarbyl polyamine is a polyisobutenyl diethylenetriamine having from 1 to 2 polyisobutenyl groups of from about 560 to about 2,000 average molecular weight.

5. A composition according to claim 2, wherein the hydrocarbyl polyamine is a polyisobutenyl triethylenetetramine having from 1 to 3 polyisobutenyl groups of from about 560 to about 2,000 average molecular weight.

6. A composition according to claim 2, wherein the hydrocarbyl polyamine is a polyisobutenyl tetraethylenepentamine having from 1 to 3 polyisobutenyl groups of from about 560 to about 2,000 average molecular weight.

7. A composition according to claim 1, wherein the coupling agent is dichlorobutene.

8. A composition according to claim 1, wherein the coupling agent is terephthaloyl chloride.

9. A composition according to claim 1, wherein the coupling agent is p-bis(chloromethyl)benzene.

10. A composition according to claim 1, wherein the coupling agent is toluene diisocyanate.

BACKGROUND OF THE INVENTION

1. Field of the Invention

Engine deposits and sludge seriously reduce the efficiency of an internal combustion engine by clogging constricted openings and reducing the clearance of moving parts. A lubricating oil must incorporate dispersant additives to be capable of maintaining sludge-forming deposits dispersed in the oil as a means of keeping the pistons and piston-rings relatively free of such deposits. Dispersant additives also minimize sludge formation in the crankcase and about the valves and gears.

The products of this invention function as dispersants to keep deposit-forming materials in an oil medium, but do not significantly increase the rate of formation of depositforming material through their own degradation products.

2. Description of the Prior Art

The hydrocarbyl-substituted polyamines which find use as reactants leading to the products of the present invention have been described in U.S. Pat. No. 3,565,804, which is chiefly concerned with their use as lubricating oil dispersants. U.S. Pat. No. 3,438,757 is concerned with fuel compositions containing hydrocarbyl-substituted polyamines.

SUMMARY OF THE INVENTION

The reaction products of long branched chain, primarily aliphatic, hydrocarbyl-substituted polyamines of from about 450 to about 10,000 average molecular weight with certain coupling agents are effective detergents/dispersants in lubricating oil compositions. The hydrocarbyl radical will normally be derived from mineral oils of relatively high molecular weight, or polyolefins, by halogenation of the hydrocarbon and displacement of the halogen with an appropriate polyamine, normally free of unsaturation. The coupling agents of value in the practice of this invention are normally telechelic, relatively low molecular weight, polyfunctional molecules such as certain polycarboxylic acids, organic polyisocyanates and polyhalides which are reactive towards the polyamine. Depending on the coupling agent chosen, the product is a complex amide, imide, polyamide, higher order amine, N-hydrocarbylurea, polyurea or other complex condensation product.

DETAILED DESCRIPTION OF THE INVENTION

The lubricating oil compositions of this invention contain the complex reaction products of certain high molecular weight branched chain, aliphatic N-hydrocarbyl alkylene polyamines with selected coupling agents which are polyfunctional low molecular weight carboxylic acids, acid halides, anhydrides, isocyanates or hydrocarbyl halides. Of course, the products of the coupling reactions are normally of higher average molecular weight than the hydrocarbyl polyamine reactants and normally consist of the condensation product of two hydrocarbyl polyamines through the coupling agent by reaction at a primary or secondary amino nitrogen of the polyamine. Considering the complexity of the polyamine reactants themselves, the several possible sites of reaction therein, and the possibility of coupling two, three or more polyamines, it is difficult to obtain a practical structural description of the product. Hence, the products are characterized by the following descriptions of the reactants and reaction conditions.

Hydrocarbyl-Substituted Polyamines

The hydrocarbyl-substituted polyamine reactants of this invention are high molecular weight branched chain aliphatic hydrocarbyl N-substituted alkylene polyamines. Hydrocarbyl, as used herein, denotes an organic radical composed solely of carbon and hydrogen, which may be aliphatic, alicyclic, or aromatic, or combinations thereof, e. g., aralky. Preferably, the hydrocarbyl groups will be relatively free of aliphatic unsaturation, i. e. ethylenic and acetylenic, particularly acetylenic. The hydrocarbyl polyamines will have average molecular weights in the range of about 450 to about 10,000, more usually in the range of about 750 to about 6,000. When the hydrocarbyl groups are of lower molecular weight, the average number of hydrocarbyl substituents in the polyamine can be greater than one. The hydrocarbyl will normally be aliphatic, having from 0 to 2 sites of unsaturation, more usually 0 to 2 sites of ethylenic unsaturation and preferably from 0 to 1 site of ethylenic unsaturation.

The hydrocarbyl group will normally be derived from a polyolefin derived from olefins of from 2 to 6 carbon atoms (ethylene being copolymerized with an olefin of at least 3 carbon atoms), or from a high molecular weight petroleum-derived hydrocarbon.

For the most part, the polyamines used in this invention will have the following formula: ##SPC1##

wherein:

U is alkylene of from 2 to 6 carbon atoms, more usually of from 2 to 3 carbon atoms, there being at least two carbon atoms between the nitrogen atoms;

a is an integer of from 0 to 10, usually of from 1 to 6, and more usually of from 1 to 4;

b is an integer of from 0 to 1 and preferably 0;

a+2b is an integer of from 1 to 10, more usually an integer of from 1 to 6 and preferably an integer of from 1 to 4;

c is an integer or fractional number (when averaged over the entire composition) in the range of from 1 to 5, preferably 1 to 3, and equal to or less than the number of nitrogen atoms in the molecule, usually on the average less than the total number of nitrogen atoms in the molecule;

R is an aliphatic or alicyclic branched chain hydrocarbyl radical derived from petroleum hydrocarbons or olefin monomers of from 2 to 6 carbon atoms, preferably of from 3 to 4 carbon atoms, ethylene being copolymerized with a higher homolog (an olefin of at least 3 carbon atoms) and having from 0 to 2 sites of aliphatic unsaturation, more usually from 0 to 2 sites of ethylenic unsaturation and preferably from 0 to 1 site of ethylenic unsaturation, having greater than 30 carbon atoms and not more than 300 carbon atoms, more usually 50 to 200 carbon atoms,

A is hydrogen, hydrocarbyl of from 1 to 10 carbon atoms or hydroxyhydrocarbyl of from 1 to 10 carbon atoms,

X is hydrogen, hydrocarbyl of from 1 to 10 carbon atoms or hydroxyhydrocarbyl of from 1 to 10 carbon atoms and may be taken together with A and the hydrogen to which A and X are attached to form a ring of from 5 to 6 annular members having from 0 to 1 oxygen annular member, 1 nitrogen annular member and from 4 to 5 carbon annular members,

x is an integer of from 0 to 1,

y is an integer of from 0 to 1, and

x+y is equal to 1.

The alkylene radical, indicated as U, will have from 2 to 6 carbon atoms, the nitrogens connected by U being separated by at least 2 carbon atoms. The alkylene group may be straight chain or branched chain, the remaining valences of the alkylene group being on different carbon atoms. Illustrative alkylene groups include ethylene, trimethylene, tetramethylene, pentamethylene, hexamethylene, 1,2-propylene, 2-methyl-1,3-propylene, 1,4-(2,3-dimethylbutylene), etc.

The hydrocarbyl radical indicated by R may be aliphatic or alicyclic and, except for adventitious amounts of aromatic structure present in petroleum mineral oils, will be free of aromatic unsaturation. The hydrocarbon groups are derived from petroleum mineral oil or polyolefins, either homo-polymers or higher order polymers, of 1-olefins of from 2 to 6 carbon atoms, ethylene being polymerized with a higher homolog. The olefins may be monoor poly-unsaturated, but the polyunsaturated olefins require that the final product be reduced to remove substantially all of the residual unsaturation.

Illustrative sources for the high molecular weight hydrocarbons from petroleum mineral oils are naphthenic brightstocks. For the polyolefin, illustrative polymers include polypropylene, polyisobutylene, poly-1-butene, copolymer of ethylene and isobutylene, copolymer of propylene and isobutylene, poly-1-pentene, poly-4-methyl-1-pentene, poly-1-hexene, poly-3-methyl-butene-1, etc.

The hydrocarbyl group will normally have at least one branch per 6 carbon atoms along the chain, preferably at least 1 branch per 4 carbon atoms along the chain, and particularly preferred that there be from 0.5 to 1 branch per carbon atom along the chain (at least 1 branch per 2 carbon atoms along the chain). These branched chain hydrocarbyl groups are readily prepared by the polymerization of olefins of from 3 to 6 carbon atoms and preferably from olefins of from 3 to 4 carbon atoms. The addition polymerizable olefins employed are normally 1-olefins. The branch will be of from 1 to 4 carbon atoms, more usually of from 1 to 2 carbon atoms and preferably methyl.

The hydrocarbyl-substituted polyamine can be a polyethylene polyamine, or polypropylene polyamine, where, for example, the polyethylene polyamine is of the general formula: ##SPC2##

wherein:

a ¹ is in the range from 1 to 5;

c ¹ is in the range from 1 to 4 and equal to or less than the number of nitrogen atoms; and

R ¹ is a branched chain aliphatic hydrocarbyl group derived from olefins of from 2 to 6 carbon atoms and of average molecular weight in the range from about 420 to about 2,000 with the proviso that when the monomer is ethylene it is copolymerized with a higher homolog.

In order to include possible variations, the generic formula does not indicate to which nitrogen atom the R group and the H atoms are bonded. Rather, free valences are indicated by bars, and the total number of R groups and H atoms indicated next to the basic polyamine structure. The generic formula employed provides a simple means for including the possible variations that will occur when a polyamine is used having non-equivalent amine nitrogens. Numerous examples and illustrative compounds within the above formula are given in U.S. Pat. Nos. 3,565,804, 3,438,757 and 3,574,576 which are incorporated herein by reference.

In preparing the hydrocarbyl-substituted polyamine reactants, rarely will a single compound be employed. With both the polymers and the petroleum-derived hydrocarbyl groups, the composition is a mixture of materials having various structures and molecular weights. Therefore in referring to molecular weight, average molecular weights are intended. Furthermore, when speaking of a particular hydrocarbyl group, it is intended that the group include the mixture that is normally contained with materials which are commercially available; that is, polyisobutylene is known to have a range of molecular weights, and may also include very small amounts of very high molecular weight materials. Furthermore, depending on the method of preparation, the end group of the polymer may vary and may be terminated not only with an isobutene group, but with a 1- or 2-butene group.

Similarly, the alkylene polyamines which are commercially available are frequently mixtures of various alkylene polyamines having 1 or 2 species dominating. Thus, in commercially available tetraethylene pentamine, there will also be small amounts of pentaethylene hexamine and triethylene tetramine. In referring to tetraethylene pentamine for example, it is intended not only to include the pure compound, but those mixtures which are obtained with commercially available alkylene polyamines. Finally, as indicated, in preparing the compounds of this invention, where the various nitrogen atoms of the alkylene polyamine are not equivalent, the product will be a mixture of the various possible isomers, and the coupling of the hydrocarbyl-substituted polyamines can produce a variety of possible final structures.

Coupling Agents

The coupling agents which function to yield dispersants of the present invention upon reaction with the high molecular weight hydrocarbyl-substituted polyamines are normally telechelic (terminally reactive) polyfunctional molecules of relatively low molecular weight. They may be classified among several general groups of polyfunctionalities. These functionalities are chemical groupings distinguished by their ability to react with primary or secondary amino nitrogen atoms in a hydrocarbyl-substituted amine to yield products in which the coupling agent is bound to said amino nitrogen by a chemical bond.

Both structure and molecular weight are important considerations with respect to the performance of hydrocarbyl-substituted amines as lubricant additives. Molecular weights are increased by the reaction of hydrocarbyl-substituted polyamines with polyfunctional compounds. Reactions with the telechelic difunctional compounds of the present invention indicate that molecular weights are, in general, doubled, indicating dimerization. Since the molecular weight of the coupling compounds are small compared to that of the hydrocarbyl-substituted polyamines, the nitrogen contents are essentially unchanged.

Dimerization also alters the chemical nature of the amino nitrogens. The product of the reaction of polybuteneethylenediamine with 1,4-dichloro-2-butene is expected to have properties which differ from that of polybutene ethylenediamine, in that all the amino nitrogens are allylic instead of only one in the starting polybutene ethylenediamine. Similarly, the use of p-bis(chloromethyl)benzene as the coupling agent gives a product containing both benzylic and allylic amines. On the other hand, the use of acid halides, or acid anhydrides, converts the amines into amides with lower total basicity as well as higher molecular weight.

1. Polycarboxylic acids, acid halides, anhydrides, or equivalents, which react with primary or secondary amino nitrogen to yield amides and polyamides, or react with primary amino nitrogen to form imides, are satisfactory coupling agents in the present invention. Examples of such polycarboxylic acids include oxalic, malonic, succinic, glutaric, adipic, pimelic, azelaic, sebacic and other α,ω-dibasic acids of relatively low molecular weight and the hydrocarbyl-substituted acids of the same name. Unsaturated polycarboxylic acids such as maleic, fumaric, itaconic are useful coupling agents, as are the substituted polycarboxylic acids such as tartronic, malic, tartaric, nitrile triacetic, and citric acids. Coupling agents include aromatic carboxylic acids and equivalents such as phthalic anhydride, terephthaloyl chloride, and preferably, pyromellitic dianhydride. In general, the polycarboxylic coupling agents will be characterized by molecular weights below about 300 and carbon numbers in the range from C ₂ to about C ₂₀

2. Organic polyisocyanates, such as toluene diisocyanate (made from 2,4-amino toluene), react with primary or secondary amino nitrogen to yield hydrocarbyl-ureas or polyureas which are satisfactory lubricating oil dispersants. Examples of such organic polyisocyanates include phenylene diisocyanate, toluene diisocyanate, methylenediphenyldiisocyanate, alkylated methylenephenyldiisocyanate, hexamethylenediisocyanate, and polymeric isocyanates, such as polymethylenepolyphenylisocyanate. In general, the organic polyisocyanate coupling agents will be characterized by molecular weights below about 400 and carbon numbers in the range from about 8 to about 20.

3. Organic polyhalides which find use within the scope of this invention are low molecular weight, telechelic, C ₂ -C ₂₀ hydrocarbyl dihalides such as 1,4-dichloro-2-butene, or p-bis-(chloromethyl)benzene, in which the halogens are attached to different carbon atoms and preferably are separated by several carbon atoms. The organic dihalides react with primary or secondary amino nitrogen to yield higher order amines. They are the preferred coupling agents of the invention because of their effectiveness.

Method of Preparation

The coupling agents are illustrated by the known, commercially available, chemicals previously discussed. The method of preparation of the hydrocarbylpolyamines has been described and illustrated with numerous examples in U.S. Pat. Nos. 3,565,804, 3,574,576 and 3,438,757 which are herein incorporated by reference. The products of this invention are prepared by reacting a coupling agent with a hydrocarbyl polyamine by directly mixing the reactants, or solublizing in a mutual solvent, such as xylene, benzene or hexane. In general, the mol ratio of the reactants can range from 1:3 to 3:1. Normally, the reactions proceed by contacting the reagents, with stirring, at temperatures from about 25°C to about 200°C for from 1 to 48 hours. The organic product is usually washed, the aqueous phase removed, and the product stripped of solvent. Infra-red spectra of the product were then taken routinely. Molecular weight measurements showed the products were largely "dimeric", i.e. correspond to the coupling of two hydrocarbyl polyamines as illustrated in the following example.

EXAMPLE I:

Polyisobutenyl ethylene diamine (500 g., 0.281 mol) wherein the polyisobutenyl is of average molecular weight 1,400, was heated to 115°C and 1,4-dichloro-2-butene (21.9 g., 0.175 mol) was added in one step. The temperature was increased to 190°C for 20 minutes, then lowered to 150°C and held for 3.5 hours. The temperature was then increased to 210°C over a 35-minute period. The mixture was cooled, diluted with 1 liter of mixed hexanes, 800 ml. of methanol and 500 ml. of dilute NaOH. The resulting mixture was heated to boiling and poured into a separatory funnel. The aqueous layer was removed and the organic layer washed with 500 ml. of boiling water. The mixture was concentrated by distillation with final stripping carried out on the solvent stripper at 100°C for 1.5 hours to obtain 456 g. of dimerized material with the following analysis: molecular weight, 2,530: percent nitrogen, 1.34.

EXAMPLE II:

Polyisobutenyl tetraethylene pentamine (464 g., 0.33 mol) wherein the polyisobutenyl is of average molecular weight 950, was heated to 80°C, followed by the one-step addition of 20.4 g. (0.163 mol) of 1,4-dichloro-2-butene. The temperature was increased to 145°C and held for 1 hour and 20 minutes. Upon cooling, 600 ml. of mixed hexanes, 600 ml. of isopropyl alcohol, and 300 ml. of water containing 15 g. of NaOH was added. The aqueous layer was removed and 150 ml. more water added, followed by shaking. The aqueous layer was removed. Final washing was carried out with 300 ml. of water. The organic layer was concentrated by distillation, with final stripping to yield 465 g. of dimer: molecular weight 2,550: percent nitrogen 4.33.

EXAMPLE III:

Polyisobutenyl ethylene diamine of Example I (100 g.., 0.056 mol) was heated to 120°C. p-bis(chloromethyl)benzene was added in one step and the temperature increased to 160°C and held for 3 hours 15 minutes. The mixture was diluted with hexane and isopropyl alcohol, washed with dilute NaOH and water, and stripped to yield 95 g. of dimer: molecular weight 2,700; percent nitrogen 1.48; IR 1680 cm ^{- 1} .

EXAMPLE IV:

Polyisobutenyl amine (206 g., 0.225 mol), wherein the polybutenyl amine is of average molecular weight 820, was heated to 110°C and 1,4-dichloro-2-butene (12.8 g., 0.113 mol) was added in one step. The mixture was heated for about seven hours with the temperature rising to 133°C. The mixture was cooled, diluted with mixed hexanes, washed with dilute sodium hydroxide then washed with water until washings were neutral. Solvent was removed from the mixture by stripping at 100°C for several hours to give 183.2 g. of partially dimerized material having the following analysis: molecular weight, 1290; percent nitrogen, 1.48.

EXAMPLE V:

25 ml. of pyridine and the polyisobutenyl ethylene diamine of Example I (100 g.) were dissolved in 50 ml. of benzene and heated to reflux. Pyromellitic dianhydride (6.1 g., 0.028 mol) and 40 ml. of hot pyridine were added drop-wise over a ten-minute period. A completely homogeneous solution resulted. Heating at reflux was continued for 1 hour 15 minutes, then solvent was removed by distillation until the temperature reached 180°C. The mixture was cooled to 150°C and held for 3 hours, then cooled to room temperature and 100 ml. of toluene and 25 ml. of n-butanol were added. The mixture was washed three times in 100 ml. portions of water containing 5 percent n-butanol, then concentrated by distillation with final stripping yielding 99 g. of product; molecular weight 3,550; percent nitrogen 1.54; IR, 1635 cm ^{- 1} (amide), and 1725 cm ^{- 1} (imide); base number of product, 19 mg KOH/g; base number of starting material, 53 mg KOH/g; acid number of product, 6.1 mg KOH/g.

EXAMPLE VI:

Terephthaloyl chloride (5.7 g., 0.028 mol) and the polyisobutenyl ethylene diamine of Example I (100 g.) were dissolved in 100 ml. of benzene and heated to reflux for 20 minutes. Solvent was removed at distillation until the temperature reached 150°C. This temperature was held for 3.5 hours, followed by work-up as in Example III giving 94 g. of material: molecular weight 3,380: percent nitrogen 1.53; IR 3,320 cm ^{- 1} (NH), 1650 cm ^{- 1} (amide); base number of starting material, 53 mg KOH/g; base number of product, 23 mg KOH/g; acid number of product, 1.8 mg KOH/g.

EXAMPLE VII:

Polyisobutenyl ethylene diamine of Example I (672 g.) was added to 150 ml. of toluene and 86.4 g. of diphenolic aciddissolved in 300 ml. of tetrahydrofuran. The mixture was stirred at 151°C for 12 hours under nitrogen. The product was stripped to 325°F and weighed 753 g.

EXAMPLE VIII:

Trimellitic anhydride (19.2 g) was mixed with polyisobutenyl ethylene diamine of Example I (672 g.) in 125 ml. of tetrahydrofuran. The mixture was stirred for 12 hours at about 163°C under nitrogen. The product was stripped to 335°F and weighed 696 g.

EXAMPLE IX:

Oleyl amine (52.6 g., 0.196 mol) in 150 ml. of xylene was heated to 100°C and 1,4-dichloro-2-butene (11.1 g., 0.098 mol) was added in one step. Heating was continued for two and one-half hours at which time the temperature had increased to 141°C. The mixture was cooled, washed with dilute sodium hydroxide, then washed with water until the washings were neutral. The mixture was stripped on the solvent stripper to give 46.5 g. of material having the following analysis: molecular weight, 700; percent nitrogen, 4.48; percent chlorine, 1.64.

EXAMPLE X:

Ethylenediamine tetra-acetic acid (29.2 g.) and 100 ml. of toluene was mixed with the polyisobutenyl ethylene diamine of Example I (896 g.). The mixture was stirred at 325°-335°F for 6 hours under a nitrogen atmosphere. About 6-7 cc. of H ₂ O was collected in a Stark trap and the product was stripped of toluene under reduced pressure.

EXAMPLE XI:

N,N-bis-(2-hydroxyethyl)glycine (81.5 g.) was mixed with polyisobutenyl ethylene diamine of Example I (1010 g.) and 150 cc. of toluene. The reaction mixture was stirred at 325°-330°F for 8 hours. The mixture was dissolved in hexane and filtered. The hexane was stripped off under reduced pressure.

EXAMPLE XII:

Itaconic acid (26 g.) was mixed with polyisobutenyl ethylene diamine (808 g.) and 150 cc. of toluene. The mixture was stirred at 325°-335°F for 12 hours under nitrogen atmosphere. The toluene was removed under reduced pressure.

EXAMPLE XIII

Polyepoxide (25 g.) was mixed with polyisobutenyl ethylene diamine of Example I (308 g.). The mixture was stirred at 280°-290°F for 8 hours under a nitrogen atmosphere. The final product was stripped to 250°F.

EXAMPLE XIV:

Epichlorohydrin (28 g.) was mixed with polyisobutenyl ethylene diamine of Example I (672 g.) and 150 cc. of toluene and the mixture was stirred at 230°-235°F for 15 hours. The mixture was stripped to 325°F under vacuum.

EXAMPLE XV:

Polyisobutenyl ethylene diamine of Example I (900 g.) was mixed with 900 g. of a neutral oil and stirred at 200°F for 15 minutes. 43.5 g. of toluene 2,4-diisocyanate was then added and the mixture stirred at 295°-320°F for 8 hours. The product was stripped, dissolved in hexane and filtered. The hexane was removed under reduced pressure.

EXAMPLE XVI:

Fumaric acid (7.78 g.) was mixed with an approximately equimolar amount of the polyisobutenyl ethylene diamine of Example I (100 g.) in 600 ml. of xylene. N ₂ was flushed during the reaction which occurred at xylene reflux temperature for 6 hours. 1.2 ml. of water was collected overhead. 500 ml. of methyl alcohol and 100 ml. of H ₂ O were added to the reaction product and the polymer layer separated from the aqueous layer. The hexane solubles were azeotroped with benzene to remove excess water and the solvents were stripped under vacuum. Molecular weight about 2,380, percent nitrogen 1.37.

EXAMPLE XVII:

Maleic anhydride (5.4 g.) was mixed with 100 g. of the polyisobutenyl ethylene diamine of Example I in 600 ml. of xylene. The reaction mixture was flushed with N ₂ and reaction occurred at the xylene reflux temperature for 6 hours. About 1 ml. of water was collected as a reaction product. The product was separated with ethanol-water several times, azeotroped with benzene and stripped under vacuum. Molecular weight about 2,997; percent nitrogen 1.33.

EXAMPLE XVIII:

d-tartaric acid (20 g.) was mixed with 100 g. of the polyisobutenyl ethylene diamine of Example I in 600 ml. of xylene. The system was flushed with nitrogen and reacted at xylene reflux temperature for 6 hours. About 5.9 ml. of water was collected as a reaction product. The polymer product was separated by adding about 500 ml. of ethanol (95 percent) and 100 ml. of water, boiling the mixture, and removing the non-aqueous layer. This was repeated. The polymer product was then azeotroped with benzene to remove the last traces of water and the product was stripped under vaccum. Molecular weight about 2,980; percent nitrogen 1.34.

Lubricating Oils

The oils which find use in this invention are oils of lubricating viscosity derived from petroleum or synthetic sources. The oils may be paraffinic, naphthenic, halogen-substituted hydrocarbons, asphaltic, or combinations thereof. Synthetic lubricating oils include hydrocarbon oils and polymerized and interpolymerized olefins, alkyl benzenes, polyphenols, alkylene oxide polymers and copolymers, and derivations thereof such as esters, ethers, etc. Silicone-based oils also form a useful class of synthetic lubricants. Carboxylic acid esters such as octyl adipate, nonyl azelate, decyl suberate, butyl alkenylsuccinate, etc.; also, inorganic esters such as phosphates and silicates are useful lubricating oils.

Oils of lubricating viscosity normally have viscosities in the range from 35-50,000 Saybolt Universal Seconds (SUS) at 100°F, more usually from about 50-10,000 SUS at 100°F.

Additives

The detergents-dispersants of the present invention may be prepared as concentrates having as high as 80 weight percent of the dispersant in lubricating oil. Generally, concentrates will vary from about 10 to 80 weight percent. However, when the oil is to be used in the engine, the amount of the detergent generally will vary from about 0.1 to 15 weight percent, more usually from about 0.25 to 10 weight percent. The lubricating oil compositions may therefore vary in the amount of detergents from 0.1 to 80 weight percent.

Preferably, the detergents of this invention are used in lubricating oils with an oxidation inhibitor and extreme pressure agent, as well as other additives. The preferred inhibitors are dithiophosphates, particularly zinc O-di(hydrocarbyl)phosphorodithioate where the hydrocarbyl groups are generally from 4 to 36 carbon atoms. Preferably, these hydrocarbyl groups are alkyl or alkaryl groups. Also, S-alkyl and S-polyalkyleneoxy esters of the phosphorodithioate may be used. Usually about 6 to 50 mM/Kg. of the phosphorodithioate is used in the oil.

Other additives may also be included in the lubricating oil. These additives include pour point depressants, viscosity index improvers, anti-wear agents, rust inhibitors, corrosion inhibitors, other detergents and dispersants, etc. Generally, the total amount of additives exclusive of the detergent will be in the range from about 0.1 to 5 weight percent of the lubricating oil composition. In concentrates, the weight percent of these additives will usually be much higher.

Evaluation

To demonstrate the wide applicability of the products within the scope of this invention, various products were tested under conditions simulating situations in which lubricating oils are used. A particularly severe test is the 180 BMEP (Brake Mean Effective Pressure in psi) Caterpillar test. The 180 BMEP Caterpillar test conditions are for a super-charged caterpillar engine wherein the pressure of the super-charged air is 70 inches Hg. abs., the water temperature of the cooling jacket is 190°F, the air temperature is 255°F, the oil temperature at the bearing is 205°F, the sulfur content of the fuel is 0.4 percent, the speed of the engine is 1800 rpm and the rate of fuel input is at a rate which provides 7,460 BTU per minute. The test is carried out for a stated number of hours as indicated in the following table. Groove deposits are then rated on a range of 0-100, 100 being completely filled grooves. The rating for land deposits is based on a range of 0-800, 800 being completely black. The rating for underhead deposits is based on a range of 0-10, 10 being completely clean.

TABLE I ______________________________________ Length Com- of posi- Test Groove Land Under- tion (hrs.) Deposits Deposits head ______________________________________ A 60 49, 6.1, 0.5, 0.5 285, 20, 25 5.3 120 74, 6.4, 0.5, 0.5 230, 20, 55 5.0 B 60 30, 6.4, 0.5, 0.5 160, 10, 15 3.8 120 69, 7.0, 0.6, 0.6 205, 15, 40 3.8 ______________________________________

The lubricating compositions of Table I consist of a neutral petroleum oil of lubricating viscosity, 100 mM/Kg of a carbonated-sulfurized calcium polypropylenephenate, 2.5 mM/kg. of calcium sulfonates, 20 mM/kg. of zinc-bis(polypropenylphenyl) dithiophosphate, and 6 percent by weight of the dispersant polyisobutenyl succinimide of triethylenetetramine, wherein the polyisobutenyl is of average molecular weight about 1,000. In composition B of Table I 6 weight percent of the reaction product of Example XV is used in place of the polyisobutenyl succinimide of triethylenetetramine. The severe conditions of the 180 BMEP Caterpillar engine test show that the product of the present invention is a superior overall dispersant. Specifically, hydrocarbylsubstituted polyamines coupled by toluene diisocyanate are shown to be superior in inhibiting groove and land deposits to a polyisobutenyl succinimide of a low molecular weight polyamine.