DE2851465A1 - OIL BASED LUBRICANT - Google Patents

Description

-I- 165 U6

PFENNING MAAS

MSMIG - LEivlKS- SPOTT

8C1-ILBSSH2.-JMERSTR 299

ÖOQO MUNICH 40

13-3642

Atlantic Richfield Company, Los Angeles, California, V. St. A.

Oil-based lubricants

The invention relates to an improved lubricant oil-based. In particular, it relates to a lubricant, its properties are improved by adding solid materials are.

Lubricating oils are conventionally used for the internal lubrication of internal combustion engines, for example prime movers for motor vehicles. Based on appropriate investigations it has been shown that the addition of certain solid materials, such as graphite, to such lubricating oils increases leads to an improvement in the fuel efficiency of the prime mover. For example, in "Stable Colloid Additives Engine Oils - Potential Improvement in Fluel Economy ", James E. Bennington et al, Society of Automotive Engineers, Fuels and Lubricants Meeting, Houston, Texas, June 3-5, 1975 reported an improvement The mileage of gasoline by 3 to 5%, if you use a conventional lubricant with 1 weight percent Offset graphite. One such improvement in fuel economy is, for example, in terms of fuel scarcity of particular economic value.

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An effective lubricant for modern internal combustion engines however, it must also meet other criteria. For example, such lubricating oils must also have certain Regulations regarding their tendency to form deposits such as paint, sludge and the like meet the machine parts. The presence of solid lubricants in such lubricating oils increases namely their tendency to form deposits. You therefore need a lubricating oil that has at least a certain one Contains solid lubricant and has adequate deposit formation properties disposes. -

The object of the invention is therefore to create an improved Oil-based lubricant. According to this, a lubricating oil containing solids is to be created, but only less tends to form deposits. Furthermore, an improved method for lubricating internal combustion engines is to be provided.

This task is solved by an oil-based lubricant from a greater amount by weight of an oil with lubricating viscosity, a lesser amount by weight of solid particles to improve the lubricating properties of this oil and a smaller amount by weight of a dispersing improver - VI, which is characterized in that this dispersing improver - VI is one of the following Substances are:

(a) a functional polymer in the form of a reaction product from (i) an oxidized higher molecular weight amorphous copolymer of essentially ethylene and propylene with a number average molecular weight of at least about 20,000 and with at least 140 out-of-chain methyl groups in 1,000

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Chain carbon atoms and of (ii) an aliphatic amine or polyamine,

(b) a graft polymer based on an olefin polymer backbone a dialkylaminoalkyl methacrylate is grafted,

(c) an interpolymer of a long chain n-alkyl methacrylate and a dialkylaminoalkyl methacrylate or an N- (alkanone) acrylamide and / or

(d) a nitrogen-containing ester of a carboxyl group-containing one Interpolymers, which consists of alpha, ß-unsaturated acids or acid anhydrides and olefins, a has reduced specific viscosity of about 0.05 to about 2 dl / g, carboxylic acid ester groups from at least Contains 8 carbon atoms and also has carbonylamino groups.

The addition of the above-mentioned dispersing improvers - VI to the present solids-containing agents results in a surprising degree of reduction in disadvantageous deposit formation, for example on components of internal combustion engines, which are lubricated with the present agent.

According to the invention, all oils customary for producing lubricating oil can be used. For example, all lubricating oils with viscosities from about 50 SUS to about 2000 SUS at 38 ^° C. are suitable. These oils can be refined or otherwise processed to form oils of the desired quality. While mineral oils are preferred, synthetic oils can just as easily be used. According to the invention, mineral oils with viscosities between approximately 100 SUS and approximately 1000 SUS at 38 ^° C. are preferably used. It

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Combinations of two or more different oils can also be used to form a single lubricant according to the invention be used. The respective lubricating oil makes up the predominant part of the present lubricant, namely preferably at least about 60 percent by weight, in particular at least about 70 percent by weight, based on the Weight of the entire remedy.

The agent according to the invention also contains a smaller one Amount by weight of solid particles by means of which the lubricating properties of such an agent can be improved. These Solid particles preferably have a greater proportion by weight or, in particular, a maximum transverse dimension as a whole between about 1 millimicron and about 2 microns, and more particularly between about 1 millimicron and about 1 micron. Suitable solid particles useful in the present invention include those materials which are useful in improving the Lubricating properties of lubricating oils are known. Individual examples of such solid particles are graphite, molybdenum disulfide, Zinc oxide, tungsten disulfide, mica, boron nitrate, borax, Silver sulfate, cadmium iodide, lead iodide, barium fluoride, Tin sulfide or mixtures thereof. According to the invention, graphite, molybdenum disulphide are preferably used as solid particles id, zinc oxide or "mixtures thereof, in particular graphite, molybdenum disulfide or mixtures thereof, and above all Graphite.

The solid particles are preferably in the agent according to the invention in an amount of about 0.05 to 5 percent by weight, in particular about 0.1 to 2%, based on the total agent, is present. The agent according to the invention The component present and consisting of solid particles is preferably in the form of a colloidal suspension, for example in a conventional lubricating oil and / or at least one conventional lubricating oil detergent.

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Such colloidal suspensions or concentrates can, for example, be about 2 to 25 percent by weight or more Contain solid particles.

All of them can be used to stabilize such colloidal suspensions from the solid particles suitable according to the invention use conventional detergents for lubricating oils. Such detergents usually contain at least one surface-active agent Compound which, when added to lubricating oils, leads to the formation of solid impurities, for example from combustion byproducts present in machine lubricating oils, can inhibit that on the metal surfaces the machine components adhere. Ash-containing metal-based detergents are suitable as suspensions containing solid particles and ashless detergents, however, the ashless detergents are preferred.

There are a number of examples of ash-containing metal-based detergents that work well with such solids-containing detergents Have suspensions used. The ashless detergents preferred for this purpose are to compounds from an oil-solubilizing tail and a polar detergent head. Most of these ashless Detergents are known and are commercially available.

Individual examples of ashless detergents include the polyaminopolyalkylene alkenyl succinimides. Furthermore, this is Amine salts of alkyl phosphoric acids are also suitable, and polyamine derivatives of long-chain hydrocarbons can also be used insert. Reaction products of alkylene polyamines and long-chain polyamines are also suitable as detergents Alkenyl succinic anhydrides and long-chain esters from Mannichbasen. The required polarity of such compounds can be achieved by groups, for example Oxygen, sulfur, phosphorus, or nitrogen

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Contains mixtures thereof. All of these suitable ashless detergents can generally be used as compounds characterize the at least one substantial .Kohlenwasserstoffteil in such a size that the connection Is oil-soluble, and contain at least one non-metallic polar part, which by its bond to the hydrocarbon part results in an essential and often practically all of the detergent action.

Examples of ashless detergents that act as stabilizers for solid particles include polyamine polyalkylenealkenyl succinimides, long-chain polyamines, dihydrocarbon-substituted polyamines, products from substituted phenols and substituted polyamines and mixtures thereof. Such compounds have the following Formulas:

Polyamine polyalkylene alkenyl succihimides

R-CH

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-K \

■ issues

Long-chain polyamines

(K ₁

Dihydrocarbyl-substituted polyamines

H-N

ν ** ι

R.

Product of substituted phenols uhdsübstituierteri Polyamihenprodukte

Tn H

CH.

OH

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R is practically a monovalent hydrocarbon radical means with about 30 to 250 carbon atoms,

R ₁ practically represents a divalent hydrocarbon radical having 1 to about 8 carbon atoms,

R “is hydrogen and / or practically a monovalent one Is a hydrocarbon radical with 1 to about 8 carbon atoms,

R practically represents a monovalent hydrocarbon radical with about 15 to 100 carbon atoms,

R. means practically a monovalent hydrocarbon radical with about 4 to 30 carbon atoms,

m is an integer from 1 to about 10, preferably 2 to about 10, and

η for 0 to about 10, preferably about 2 to about 6, stands.

The radicals R and R_ are preferably alkenyl, in particular polypropenyl and / or polyisobutenyl. The radicals R _{1 are} preferably, independently of one another, alkylene having 1 to about 8 carbon atoms, in particular 2 to about 6 carbon atoms. Individual examples of suitable alkylene radicals R ₁ are methylene, ethylene, propylene, butylene, hexylene or octylene. Although the radicals R ₁ can be independent of one another, they preferably each have the same meaning in a particular ashless detergent.

The monovalent hydrocarbon radicals that are independent of one another R "contain 1 to about 8 carbon atoms, preferably 1 to about 4 carbon atoms. To these coal

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Hydrogen radicals include alkyl, such as methyl, ethyl, propyl, butyl, hexyl or octyl, alkenyl, such as ethenyl, propenyl, butenyl, Hexenyl or octenyl, aryl, alkaryl, aralkyl, alkenaryl or aralkenyl, such as phenyl, methylphenyl, phenylethyl, Ethenylphenyl or phenylethenyl.

The hydrocarbon radicals R- contain 2 to about 30 carbon atoms, preferably about 4 to 24 carbon atoms. These radicals can be straight-chain, branched, saturated, unsaturated, aliphatic (cycloaliphatic) or aromatic radicals or combinations thereof. Such radicals R. are therefore, for example, alkyl, such as butyl, octyl, decyl, dodecyl, octadecyl or C ₉₄ -alkyl, alkenyl, such as butenyl, octenyl, dodecenyl, octadecenyl or C >> alkenyl, or aryl, alkaryl, aralkyl, alkenaryl or aralkenyl, such as phenyl, benzyl, naphthyl, ethylphenyl, decylphenyl, octadecylphenyl, phenylbutyl, phenyldecyl, phenyloctadecyl, butenylphenyl, decenylphenyl, octadecenylphenyl, phenylbutenyl, phenyldecenyl or phenyloctadecenyl. The radicals R 1 are preferably alkyl or alkenyl with about 10 to 24 carbon atoms.

The radicals Rt- denote, independently of one another, alkyl with. 4 to about 30 carbon atoms, preferably about 8 to 20 carbon atoms. Examples of such radicals R_ are Aitiyl, Octyl, Decyl or octadecyl. The rest of the formula

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the acid salts of substituted phenyl and substituted polyamine can be represented by, for example, alkyl naphthols and the like Be replaced by derivatives of biphenyl, terphenyl, phenanthrene or anthracene.

Specifying practically or essentially hydrocarbon residues in the present context, radicals are to be understood which are composed predominantly of carbon and hydrogen and also contain radicals which additionally have smaller amounts of substituents, such as oxygen, halogen, sulfur or nitrogen, which do not significantly affect the hydrocarbon character of such residues.

See individual examples of ashless detergents of the above type, other suitable ashless detergents and methods Their production can be found in the following US patents: 3,237,614, 3,018,247, 3,513,093, 3,753,670, 3 008 993, 3 275 554, 3 473 011, 3 574 576, 3 576 743, 3 578 422, 3 597 174, 3 369 110, 3 652 240, 3 655 351, 3 658 494, 3 658 495, 3 676 089, 3 701 640, 3 711 255 ,. 3 717 447, 3 728 091, 3 746 520, 3 751 255, 3 756 793, 3,762,889, 3,764,281, 3,765,850, 3,773,479, 3,752,657, 3,753,670, 3,779,724 and 3,782,912.

The oil-based lubricants of the invention must, as already mentioned above, contain certain dispersing improvers - VI of the type already indicated.

Such dispersing improvers - VI suitable according to the invention include, inter alia, the following:

Functional polymers that are produced, for example, by reacting an oxidized copolymer of practically ethylene and propylene with an aliphatic amine or an aliphatic polyamine ^{at about 60 to 177 0 C and the}

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retained reaction product wins. The reactants are used in a molar ratio of from about 1: 2 to about 1:20.

Aldehydes can also be used as such additives. Such functional polymers based on aldehydes are obtained by reacting, for example, an oxidized copolymer of ethylene and propylene with a formaldehyde-forming reactant and an aliphatic amine or an aliphatic polyamine at about 121 to 177 ^° C. and the resulting reaction product is recovered. The reactants are used in a molar ratio of 1: 2: 2 to about 1:20:20.

Functional ones which can be used in accordance with the invention in the manufacture Polymeric is preferably made in the presence of a non-reactive organic solvent or diluent worked, for example an aromatic hydrocarbon such as benzene, xylene or toluene, or an aliphatic Hydrocarbon such as hexane. Particularly suitable a low-viscosity hydrocarbon oil as solvent or diluent, for example, an SAE 5W mineral oil extracted with a solvent. Using a solvent or diluent makes the reactants easier to use mix and better control the reaction temperatures.

In the above sense, copolymers are understood as meaning amorphous copolymers composed essentially of ethylene and propylene. Such copolymers can, however, also contain small amounts, for example amounts of up to 10%, based on the molar amounts of the monometric ethylene and propylene units present in the copolymer, of polymer units derived from other olefin monomers. Such other olefinic monomers include olefins of the general formula RCH = CH ₂ , where R is aliphatic or cycloaliphatic radicals with 2 to about 20 carbon atoms, such as butene-1, hexene-1, 4-methylpentene, decene-1, vinylidene norbornene or 5- Methylene-2-norbonen. Other olefinic monomers, wel-

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before multiple double bonds are used, and in particular diolefins with about 4 to 25 carbon atoms, such as 1,4-butadiene, 1,3-hexadiene, 1,4-pentadiene, 2-methyl-1,5-hexadiene or 1,7-octadiene.

Suitable ethylene propylene copolymers contain about 30 to 65, preferably about 35 to 45, mole percent propylene have a number average molecular weight of at least about 20,000, for example from about 21,500 to about 200,000 or more, preferably from about 25,000 to 40,000, and contain at least 140, in particular at least 150, pendent methyl groups for 1000 chain carbon atoms.

Ethylene propylene copolymers with the following properties are particularly suitable:

number average molecular weight 25,000 - 35

mole percentage of propylene monomer 38-42

pending methyl groups on 1000 chain carbon atoms 160-170

inherent viscosity 1.7 - 2.0 (A)

Gardner viscosity U-V (B)

Mooney viscosity 20 - 35 (C)

(A) 0.1 g copolymer in 100 cm ³ decalin at 135 ^° C.

(B) 8.0% copolymer in toluene at 25 ^° C.

(C) ASTM D-1646

The above copolymers can be prepared by known methods. Suitable manufacturing methods are among others described in the following US patents: 2,700,633,

2 726 231, 2 792 288, 2 933 480, 3 000 866, 3 063 973 or

3,093,621.

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The oxidation of such copolymers can be achieved by the respective copolymer under suitable temperature conditions at atmospheric or elevated pressure an oxidizing agent such as air or free oxygen, or another suitable for releasing oxygen converts oxygen-containing material under oxidation conditions. The oxidation can be carried out if desired perform in the presence of known oxidation catalysts, such as platinum or metals of the platinum group or compounds, which contain metals such as copper, iron, cobalt, cadmium, manganese or vanadium. The oxidation can be carried out by methods such as those described in U.S. Patents 2,982,728, 3,316,177, 3,153,025, 3,365,499, and 3,544,520.

The oxidation can be generally carried out in dependence on the particular oxidizing agent over a broad temperature range, and use of active oxidizing agents such as s0_, can be carried out at temperatures from -40 to 204 ⁰ C, while with the use of less active oxidizing agents, such as air , Temperatures from 38 to 427 ⁰ C can be used. Depending on the extent of the desired rate of oxidation, the oxidation can be carried out at subatmospheric, atmospheric or superatmospheric pressure and in the presence or absence of an oxidation catalyst. Temperature conditions, pressure conditions, oxygen content of the oxidizing agent, rate of addition of the oxidizing agent and any catalyst present are related to one another and can be adjusted in each case within the scope of the expert knowledge in such a way that the desired optimal results are achieved.

A method for oxidizing a copolymer is described in detail below.

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A copolymer of ethylene and propylene (one part) with a number average molecular weight of about 28,000 is placed in an open reaction vessel, mixed with a solvent-extracted mineral oil SAE 5W (9 parts) and the resulting mixture is then stirred while heating to 182 ° C and under an inert gas atmosphere until the rubber-like polymer has dissolved in the solvent. For the oxidation of the copolymer to the resulting mixture then rapidly stirred at a temperature of 182 ⁰ C in an atmosphere of 50% air and 5O% nitrogen. Working with a 50:50 mixture of air and nitrogen should prevent any formation of an explosive mixture. The reaction is continued under the specified conditions for 2.5 to 4.0 hours. About 2.5 to 4.5 oxygen atoms per molecule of copolymer are introduced under these oxidation conditions.

The amine reactants used to prepare the functional polymers of the invention are primary or secondary aliphatic amines or diamines of the general formula H ₉ N (CH ₉ ) NH ₉ , where y is 3 to 10, these amines or diamines up to about Containing 10 carbon atoms in the alkyl group, or polyalkylenepolyamines of the general formula

HN- (A-N) H.

A is a divalent alkylene radical with about 2 to 6 carbon atoms means and

χ stands for 1 to about 10.

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Examples of suitable amines are methylamine, dibutylamine, Cyclohexylamine, propylamine, decylamine, ethylenediamine, Triethylenediamine, tetramethylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylene pentamine, Tripropylenetetramine, tetrapropylenepentamine and other polyalkylenepolyamines, whose alkylene groups are expedient contain up to about 10 carbon atoms.

Examples of aldehydes suitable according to the invention are aliphatic Aldehydes, such as formaldehyde, acetaldehyde or ß-hydroxybutylaldehyde. Formaldehyde or formaldehyde-forming compounds, such as pareformaldehyde or formalin, are preferred.

The aminated and oxidized ones suitable according to the invention Copolymers can generally have number average molecular weights between about 1500 and 20,000, they however, preferably have number average molecular weights between about 20,000 and 200,000 or above, and most preferably number average molecular weights between about 25,000 and 40,000.

The chemical composition of the reaction products that contain the functional polymers can be determined by a not precisely characterize chemical structural formula. In the oxidation of the respective copolymers, however, should predominate Ketones as well as small amounts of aldehydes, acids and possibly also esters are formed. As a result of the complex The nature of these oxidized reaction products cannot be determined by their chemical structure, their exact composition it must be defined by its manufacturing process.

Further examples according to the invention suitable dispersion improvers - VI are also certain nitrogen-containing polymers.

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A preferred nitrogen-containing polymer is a graft polymer with a dialkylaminomethacrylate on its polymer backbone or a mixture of dialkylaminomethacrylates is grafted.

A second preferred nitrogen-containing polymer is one of a long chain n-alkyl methacrylate and a dialkylaminoalkyl methacrylate or an N- (alkanone) acrylamide produced oil-soluble interpolymer.

The nitrogen-containing graft polymers suitable according to the invention can be produced using conventional methods. A suitable method for this is, for example, im the following two-step process.

The first stage of this process is that an oil-soluble, practically linear terpolymer of ethylene, a terminally unsaturated straight-chain alkene having 3 to about 12 carbon atoms and a terminally unsaturated nonconjugated alkadiene having 5 to about 8 carbon atoms, which has an average carbon chain length of about 700 to 7000 and has an inherent viscosity of about 0.6 to about 1.9 in the form of a 0.10 percent by weight solution in tetrachlorethylene at 30 ⁰ C, with a lithium alkyl having 3 to about 10 carbon atoms in the presence of a liquid alkane as solvent with about 5 to 10 carbon atoms and with N, N, N ', W-tetraalkylalkylenediamine as a promoter, in which the alkyl and alkylene radicals have 1 to about 4 carbon atoms, react with one another to form a lithiated terpolymer as an intermediate product. The reaction is preferably carried out under anhydrous conditions (less than 0.01 percent by weight water) and in an inert atmosphere, for example nitrogen, and at temperatures between about 20 and 100 ^° C. over a period of 1 to 25 hours. Preferably in this

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first stage worked using about 10 to 200 mol of lithium alkyl per 100 g of terpolymer, the molar ratio of lithium alkyl to the diamine used as a promoter is about 0.40 to 2 "O "

In the second stage of this process, the lithiated hydrocarbon terpolymer obtained as an intermediate is treated with a monomeric aminoalkyl methacrylate of the formula

CH ₃

1 2

wherein R "and R ¹ is alkyl having from. 1 or 2 carbon atoms, and A is a divalent alkylene radical having 2 to about 4 carbon atoms, preferably at temperatures between about 100 and -100 ⁰ C, under anhydrous conditions and in inert atmosphere to give operates at a weight ratio of lithiated intermediate to total monomer of about 0.2: 1 to about 1000: 1. The reaction time in this second stage is preferably about 0.5 to 24 hours.

The reaction mixture obtained in this second stage is used to obtain the desired graft polymers in the usual way Wise worked up by using the reaction mixture to destroy the lithium alkyl and the promoter For example, about 0.1 to 10 percent by weight of a lower alkanol with 1 to 4 carbon atoms is added to diamines and the resulting solution then first with dilute aqueous mineral acid (for example 5 to 10

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weight percent aqueous hydrochloric acid) and then washed with water and the material obtained in this way then, if desired, further purified in the usual way " for example subjecting it to a precipitation"

In the first stage of the above implementation, along the Terpolymer chain incorporated arbitrarily lithium residues, and these lithium residues are then used in the formation of the graft polymer replaced by Polymethacrylates te.

Examples of Alkenkomponenten in Terpolymerreaktanten are propylene, 1-butene, 1-pentene "1-hexene _f I-heptene, 1-octene, 1-nonene, 1-decene and 1-dodecene, examples of suitable Allcadienkomponenten in this Terpolymerreaktanten are 1, 4-pentadiene, 1,4-hexadiene, 1,5-hexadiene, 2-methyl-1,5-hexadiene, 1,6-heptadiene and 1,7-octadiene. The terpolymer is preferably composed of about 40 to 55 percent by weight ethylene, about 40 to 60 percent by weight propylene and about 1 to 5 percent by weight 1,4-hexadiene and preferably has a chain length of about 800 to 5000 carbon atoms. Excellent results have been obtained with a terpolymer reactant that contains 50.5 percent by weight ethylene, 46 percent by weight propylene, and 3.5 percent by weight 1,4-hexadiene and has a chain length of about 900 to 2600 carbon atoms.

Examples of suitable monomeric dialkylaminoalkyl methacrylates are N, N-dimethylaminoethyl methacrylate, Ν, Ν-diethylaminoethyl methacrylate, N, N-dimethylaminopropyl methacrylate and N, N-diethylaminopropyl methacrylate.

Examples of suitable lithium alkyl compounds are lithium butyl, lithium hexyl, lithium octyl and lithium decyl.

Examples of suitable Ν, Ν, Ν ¹ , N ¹ -tetraalkylalkylenediamines are Ν, Ν, Ν ¹ , N'-tetramethylethylenediamine, Ν, Ν, Ν ¹ , N'-tetramethy! Propylenediamine, N, N, N ', N' -Tetramethylbutylenediamine and Ν, Ν, Ν ', N ¹ -tetrabutylmethylenediamine.

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Examples of suitable inert solvents for carrying out the above reaction are hexane, cyclohexane or heptane.

The nitrogen-containing interpolymers which can be used in the lubricants according to the invention are oil-soluble interpolymers which are produced from a long-chain n-alkyl methacrylate and a dialkylaminoalkyl methacrylate or an N- (alkanone) acrylamide. These interpolymers preferably have a number average molecular weight of less than about 120,000. These interpolymers are prepared by complete polymerization of the respective monomer or the respective monomer mixture in bulk, in solution or in dispersion using known polymerization catalysts, for example azo catalysts, such as azobisisobutyric acid nitrxl, according to US Pat. PS 2,471,959 or known peroxide catalysts, such as benzoyl peroxide or lauroyl peroxide, the respective catalysts being used in amounts of about 0.1 to 5 percent by weight. The polymerization is usually carried out at temperatures between about 50 and 150 ^° C., preferably 80 and 100 ^° C., and normally in an inert atmosphere, such as nitrogen or carbon dioxide, to prevent undesired oxidation. During the polymerization, samples are taken periodically and examined accordingly, determining their refractive index. The polymerization reaction is continued until the refractive index remains relatively constant, the reaction time normally being 1 to 10 hours.

For the preparation of suitable nitrogen-containing interpolymers, for example n-alkyl methacrylates and dialkylaminoalkyl methacrylates or N- (alkanone) acrylamides can be used as monomers. The η-alkyl methacrylates used as monomers generally contain about 4 to 22 carbon atoms, preferably about 12 to 18 carbon atoms, in the aliphatic

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Carbon chain. Methacrylates of this type are customary Esterification of methacrylic acid formed with technically pure long-chain primary alcohols. With these im Commercially available alcohols are mixtures of n-alkanols of different chain lengths, which are about 4 to 22 carbon atoms in the alkyl group. Alcohol mixtures of this type, for example, under the trade name Neodole from Shell Chemical Corporation or sold under the tradename Alfole by Continental Oil Company. Two such and suitable according to the invention Alcohols have the following analysis:

Typical properties: approximate homolog distribution in percent by weight

Neodol 25L
(synthetic lauryl alcohol)

lighter than C.-OH 12th OH C. 13th OH C. 14th OH C. 15th OH C. 16 OH C.

24 24 24

Alfol 1620 SP

(synthetic stearyl alcohol)
C ₁₄ OH and lighter 4

C ₁₆ OH 55

C ₁₈ OH 27

C ₂₀ OH 9

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Dialkylaminoalkyl methacrylates, for example, can be used as nitrogen-containing monomers for the production of nitrogen-containing interpolymers suitable according to the invention. Di-C ₁ -C, -alkylamina-C.-C, -alkyl methacrylates are preferred as dialkylaminoalkyl methacrylates. Examples of such monomeric methacrylates are diethylaminopropyl methacrylate, dimethylaminopropyl methacrylate, propylaminomethacrylate and butylaminobutyl methacrylate. Dimethylaminoethmethacrylate is particularly suitable

Other suitable nitrogen-containing monomers are acrylamides. Preferred acrylamides are N- (1,1-dimethy! Butan-3-one) acrylamide and N- (1,2-dimethyl-1-ethylbutan-3-one) acrylamide.

The oil-based lubricants according to the invention contain preferably about 0.1 to 12 percent by weight, in particular about 3 to 10 percent by weight, based on the total agent, at least one of the nitrogen-containing polymers described above. The amount by weight of this nitrogenous Polymers in the lubricants of the invention preferably corresponds to at least the amount of solid particles present, such as graphite or molybdenum disulfide. In particular makes the amount of polymer at least about twice, and most importantly at least about three times, the amount on solid particles.

To other dispersing improvers suitable according to the invention - VI include certain nitrogen-containing esters containing carboxyl groups Interpolymer. Preferred nitrogen-containing mixed esters of carboxyl group-containing interpolymers are Polymers with a reduced specific viscosity of about 0.05 to 2. These interpolymers are characterized by this from the fact that they have carboxylic acid ester groups in their polymer structure having at least 8 aliphatic carbon atoms in the ester

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rest included. The preferred interpolymers have in their polymer structure has at least the three pendent polar groups indicated below;

(A) A relatively high molecular weight carboxylic acid ester group with at least 8 aliphatic carbon atoms in the ester residue,

(B) a relatively low molecular weight carboxylic acid ester group having not more than 7 aliphatic carbon atoms in the ester residue,

(C) a CarbonyIpolyamxnogruppe _f. Which is derived from a polyamino compound with a primary or secondary amino group »

The molar ratio of (A) to (B) to (C) is about (60-90) :( 10-30) :( 2-15).

The ester is preferably a mixed ester, namely an ester having both a high molecular weight ester group and a Contains low molecular weight ester group, in particular in the ratio given above.

The ester residues have the formula

-C (O) (OR ¹ ),

and the number of carbon atoms in such an ester residue thus represents the total amount of carbon atoms the carbonyl group and carbon atoms from the ester group, namely the group (OR ').

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Another important element of the nitrogen-containing ester interpolymers is seen in the fact that they are a Must have carbonyl polyamino group which is derived from at least one nitrogen-containing compound, namely (1) a polyamino compound having a primary or secondary amino group, (2) hydrazine or a hydrocarbon substituted hydrazine or (3) mixtures thereof.

Another important characteristic of the ester interpolymers is the degree of esterification in relation to the degree of neutralization of the non-esterified carboxyl groups of the carboxyl group-containing interpolymer, which is converted into polyamino-containing Groups results. The relative molar ratio of high molecular weight ester groups to low molecular weight ester groups to polyamino groups is approximately (6Ot9O): (10-30): (2-15). Preferably this molar ratio is about (70-80): (19-25): 5. The carbonyl polyamino group can via amide, imide or amidine, and any such linkage is suitable according to the invention. By specifying carbonyl polyamino should therefore include the amino group in the definition of the the interpolymers used in the present lubricants.

Another important characteristic of the mixed ester interpolymers is their molecular weight. For the sake of simplicity, their molecular weight is reduced by the so-called specific Expressed in terms of the viscosity of the interpolymer, which is a recognized measure for determining the molecular size a polymeric substance. The reduced specific viscosity, which is abbreviated as RSV, results from the following equation:

_Rsv _ Relative Viscosity " Concentration

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The relative viscosity required for this is determined by appropriate measurement, namely using a so-called dilution viscometer, by measuring the viscosity of a solution of 1 g of the respective interpolymer in 100 ml of acetone and the viscosity of acetone in each case at 30 °. - 0.02 ⁰ C determined. For the purpose of making the calculation of the above formula easier, the concentration of the interpolymer is adjusted to 0.4 g per 100 ml of acetone. Further details about the reduced specific viscosity, which is also referred to as the specific viscosity, and its relationship to the number average molecular weight of an interpolymer can be found in Paul J. Flory, Principles of Polymer Chemistry (1953 edition), page 308 ff.

According to the invention, interpolymers are generally those with a reduced specific viscosity of about 0.05 to 2 are suitable, but interpolymers with are preferred a reduced specific viscosity of about 0.3 to 1. Interpolymers with a reduced viscosity are particularly suitable specific viscosity of about 0.5 to 1.

For technical and economic reasons, preference is given to using nitrogen-containing mixed esters and their high molecular weight Ester group has about 8 to 24 aliphatic carbon atoms and its low molecular weight ester group has about Contains 3 to 5 carbon atoms.

Examples of high molecular weight carboxylic acid ester groups, namely groups with the ester residue (OR ')', namely - (0) (OR ¹ ), are heptyloxy, isooctyloxy, decyloxy, dodecyloxy, tridecyloxy, pentadecyloxy, octadecyloxy, eicosyloxy, tricosacosyloxy, tetracosyloxy, tricosacosyloxy, tetracosyloxy, tricosacosyloxy, tricosacosyloxy, (OR 1) , Hentriacontyloxy or tetracontyloxy. Examples of such low molecular weight groups include methyloxy, ethyloxy, n-propyloxy, isopropyloxy, n-butyloxy, s-butyloxy, iso-butyloxy,

909841/0484

ii $ 185 146

n-pentyloxy, neopentyloxy, n-henyloxy, cyclohexyloxy, Cyclopentyloxy, 2-methylbutyloxy or 2,3-dimethylbutyl-1-oxy. Suitably sized alkoxy groups are generally preferred as the high molecular weight and low molecular weight ester groups. Such ester groups can also contain polar substituents. Examples of suitable polar substituents are chlorine, bromine, ether or nitro.

The carbonyl polyamino groups of the nitrogen-containing esters used according to the invention are derived from (1) polyamino compounds with a primary or secondary amino group and / or (2) hydrazine and / or hydrocarbon-substituted Hydrazine.

Preferred polyamino compounds for forming these groups are the primary aminoalkyl-substituted tertiary amines, the heterocyclic amines being particularly preferred will.

Examples of the carbonyl polyamino groups therefore include those which are different from polyamino compounds having a primary or secondary amino group and at least one monofunctional amino group, such as a tertiary amino group or a heterocyclic amino group. Such compounds can therefore be tertiary amino-substituted primary or secondary amines or other substituted primary or secondary amines whose substituents are derived are of pyrroles, pyrrolidones, caprolactams, oxazolidones, oxazoles, thiazoles, pyrazoles, pyrazolines, imidazoles, Imidazolines, thiazines, oxazines, diazines, oxycarbamyl, thiocarbamyl, uracils, hydantoins, thiohydantoins, Guanidines, ureas, sulfonamides, phosphoramides, phenolthiazines or amidines. Examples of such polyamino compounds are dimethylaminoethylamine, dibutylaminoethylamine, 3-dimethylamino-1-propylamine, 4-methylethylamino-1-butylamine, ' Pyridylethylamine, N-morpholinoethylamine, tadrahydropyridylethylamine, Bis (dimethylamino) propylamine,

909841/0484

-r-

-J {".I85U6S

Bis (diethylamino) ethylamine, N, N-dimethyl-p-phenylenediamine, Piperidylethylamine, 1-aminoethylpyrazone, 1 - (!! ethylamino) -pyrazoline, i-methyl-4-aminooctylpyrazole, 1-aminobutylimidazole, 4-aminoethylthiazole, 2-aminoethyltriazine, dimethylcar bamylpropylamine, N-methyl-N-aminopropylacetamide, N-aminoethylsuccinimide, N-methylaminomaleimide, N-aminobutyl-alphachlorosuccinimide, 3-aminoethyluracil, 2-aminoethylpyridine, o-Aminoethyl-NjN-dimethylbenzenesulfamide, N-aminoethylphenothiazine, N-aminoethylacetamidine, i-aminophenyl-2-methylimidazoline or N-methyl-N-aminoethyl-S-ethyldithiocarbamate. The following amines are mostly those which have only one primary or secondary amino group contain and preferably have at least one tertiary amino group. The tertiary amino group preferably represents a heterocyclic amino group. The polyamino compounds can occasionally contain up to about 6 amino groups have, but in most cases they contain one primary amino group and either one or two tertiary ones Amino groups. The polyamino compounds can be act aromatic or aliphatic amines, the heterocyclic amines being preferred, such as the aminoalkyl-substituted Morpholines, piperazines, pyridines, benzopyrroles, quinolines or pyrroles. They are usually amines with about 4 to 30 carbon atoms, preferably about 4 to 12 Carbon atoms. The polyamines can also contain polar substituents.

The carbonyl polyamino groups to be used according to the invention nitrogen-containing esters can also contain groups that differ from hydrazine and / or hydrocarbon

^{Derive s} substituted hydrazine, for example mono-, d "i-, tri- or tetrahydrocarbon-substituted hydrazines, the hydrocarbon substituent of which is an aliphatic or aromatic substituent, for example alkyl, such as

909841/0484

a cyclic and / or acrylic group, aryl, alkylaryl or aralkyl. Contain the hydrocarbon substituents generally up to about 24 aliphatic carbon atoms and preferably up to about 12 aliphatic carbon atoms. Preferred substituents are phenyl, alky! Phenyl or Alkyl, in which the alkyl is methyl, ethyl, propyl, butyl, pentyl, Is octyl, cyclohexyl, decyl or dodecyl. Other examples for suitable hydrocarbon groups are octyldecyl, Behenyl, benzyl, heptaphenyl, alpha-naphthy1, ß-naphthyl, Butylnaphthyl, oleyl or stearyl. A preferred class from the various hydrocarbon-substituted hydrazines represent the N, N-dihydrocarbyl-substituted hydrazines like the dimethyl, diethyl, diphenyl or dibutyl hydrazines.

The interpolymers containing carboxyl groups include, in principle, interpolymers of alpha, beta-unsaturated acids or acid anhydrides, such as maleic anhydride or itaconic anhydride, and (aromatic or aliphatic) olefins such as ethylene, propylene, styrene or isobutene. Styrene maleic anhydride interpolymers are particularly preferred. They can be prepared by polymerizing equal molar amounts of styrene and maleic anhydride with or without the use of one or more further interpolymerizable comonomers. An aliphatic olefin such as ethylene, propylene or isobutene can also be used instead of styrene. Acrylic acid, methacrylic acid or esters thereof can also be used instead of maleic anhydride. Such interpolymers are known, so that a more detailed description can be omitted. Working with a interpolymerizable comonomer, this should be present in a relatively small amount, generally in an amount of less than about 0.3 mole, preferably less than about 0.15 MoI ₇ per mole of styrene or maleic anhydride. the

909841/0484

185H6S

Various methods for the interpolymerization of styrene and maleic anhydride are known to the person skilled in the art, so that they do not need to be discussed in detail. Examples of suitable interpolymerizable comonomers are Vinyl monomers such as vinyl acetate, acrylonitrile, methacrylate, methyl methacrylate, acrylic acid, vinyl methyl ether, vinyl ethyl ether, Vinyl chloride or isobutene.

The preferred nitrogen-containing mixed esters can best be prepared by adding the respective carboxyl group-containing Interpolymer first with a relatively high molecular weight alcohol and a relatively low molecular weight alcohol Alcohol is esterified such that at least about 50% and no more than about 98% of the carboxyl groups of the Interpolymers are converted into ester residues, and the remaining carboxyl groups then with a polyamine of the above described type neutralized. To introduce the preferred amounts of the two alcohol groups into the interpolymer should work under .a molar ratio of high molecular weight alcohol to low molecular weight alcohol of about 2: 1 to 9: 1 will. In particular, this molar ratio should be about 2.5: 1 to 5: 1. The method can also be used using be carried out by more than just one high molecular weight alcohol or low molecular weight alcohol. So let yourself for this purpose, for example, use commercially available alcohol mixtures, such as the so-called oxo alcohols, which are are mixtures of alcohols with 8 to about 24 carbon atoms. Commercially available ones are particularly suitable for this purpose Alcohols or mixtures of alcohols containing at least 7 aliphatic carbon atoms, for example Octyl alcohol, decyl alcohol, dodeoyl alcohol, tetradecy! Alcohol, Pentadecyl alcohol, eicosyl alcohol and octadecyl alcohol. Other alcohols which can be used in this process are those which after appropriate esterification, the ester groups listed above result.

909841/0484

385H6S

The extent of esterification can, according to the above, be a conversion of about 50 to 98% of that present in the interpolymer Carboxyl groups correspond to ester groups, resulting in a partially esterified interpolymer. Preferably the degree of esterification should correspond to about 75 to 95%.

The necessary esterification can be achieved by simply heating the carboxyl group-containing interpolymer and the alcohol or alcohols under conditions in which a corresponding esterification occurs. Such conditions consist in working at temperatures of at least about 80 ^° C., preferably about 150 to 350 ^° C., provided the respective temperature is below the decomposition point of the reaction mixture, and removing the water formed during the esterification. To do this, you can work with an excess of alcohol, which makes the esterification reaction easy, use a solvent or diluent, for example mineral oil, toluene, benzene or xylene, and work with an esterification catalyst, such as toluenesulfonic acid, sulfuric acid, aluminum chloride, boron trifluoride-triethylamine, hydrochloric acid, ammonium sulfate , Phosphoric acid or sodium methoxide. The conditions and process modifications to be observed in each case are known to the person skilled in the art.

A particularly suitable process for mixed esterification consists in the fact that the respective carboxyl group-containing Interpolymer first reacts with the relatively high molecular weight alcohol and partially esterified the obtained Interpolymer then reacts with the relatively low molecular weight alcohol. A modification of this procedure consists in starting the esterification with the relatively high molecular weight alcohol and before the end of the esterification then introduces the relatively low molecular weight alcohol into the reaction mass, so that a mixed esterification results. Preferred interpolymers "are obtained from

9098 41/0484

185U6S

a two-stage esterification process, in which the carboxyl group-containing interpolymer first esterified with the high molecular weight alcohol that about 50 to 75% of the existing carboxyl groups are converted into ester groups, and the partially esterified interpolymer thus obtained then brings it to the desired degree of esterification by esterification with the low molecular weight alcohol.

The non-esterified carboxylic acid groups in the partially esterified interpolymer obtained in the above manner sets to form the nitrogen-containing esters required according to the invention, then with a nitrogen-containing compound around, such as with a polyamino compound and / or hydrazine.

For this purpose, the esterified interpolymer can be treated, for example, with an amount of a polyamino compound such that practically all of the non-esterified carboxyl groups present in the interpolymer are neutralized. The neutralization is preferably carried out at a temperature of at least about 80 ^° C., and usually at temperatures between about 120 and 300 ^° C., provided the temperature does not exceed the decomposition point of the reaction mass. As a rule, the neutralization temperature is about 150 to 250 ^° C. In general, it is advisable to work with a small stoichiometric excess of polyamino compound in order to ensure that the neutralization is practically terminated, so that no more than about 2% of the carboxyl groups originally present in the interpolymer are unneutralized remain and the ester obtained ideally no longer has any titratable acidity. .

The unreacted carboxylic acid residues can also be used to form the required carbonyl polyamino groups small effective amount of hydrazine or hydrocarbon substitutes

909841/0484

-185U69

tuierten hydrazine are implemented. The hydrazines can be used in the form of hydrates, hydrogen halide salts, sulfate salts or hydrogen sulfate salts. The reaction with hydrazine or hydrocarbon-substituted hydrazine is expediently carried out at temperatures between about 80 and 300 ^° C. Temperatures between about 80 and 350 ^° C. or above can be used if the temperature remains below the decomposition point of the reactants and reaction products.

To carry out this process, for example, at least about 50 mol percent, expediently 50 to 98 mol percent, of the carboxyl groups of a styrene maleic acid interpolymer are esterified with a high molecular weight aliphatic alcohol and the esterified interpolymer obtained is then reacted with hydrazine or substituted hydrazine in such a way that a nitrogen-containing ester is obtained about 2.0 to 50 or 2.0 to 35 mol percent of the carboxyl groups present are converted into carbonyl polyamino groups. The interpolymer esterified with alcohol is preferably reacted with hydrazine or a hydrocarbon-substituted hydrazine in such a way that practically complete neutralization of all non-esterified carboxyl groups of the interpolymer occurs. The reaction with hydrazine is preferably carried out at about 100 to 350 ⁰ C. By operating with excess hydrazine, the neutralization is carried out in most cases at temperatures between about 150 and 250 ⁰ C. If one wants to neutralize practically all present in the interpolymer carbpxylgruppenhaltigen unesterified CarboxyIreste, then it is advisable to work with a stöchiometrisehen Überschuß.an hydrazine.

909841/0484

1 * 51499

Suitable nitrogen-containing esters containing carboxyl groups Interpolymers are disclosed in U.S. Pat. No. 3,702,300; US Pat. No. 3,956,149 and U.S. Patent 3,959,159.

The oil-based lubricants according to the invention contain preferably about 0.1 to 20 percent by weight, in particular about 3 to 10 percent by weight, based on the total Agent, at least one dispersion improver according to the invention - VI. Those in a lubricant according to the invention Amount by weight of such dispersing improvers present on an oil basis - VI preferably corresponds to at least the amount of solid particles present, such as graphite or molybdenum disulfite. In particular, the crowd does of dispersing improvers - VI at least about twice, in particular at least about three times, the amount of present solid particles.

The oil-based lubricant according to the invention is combined in an advantageous combination of high lubricating effect, favorable dispersant-detergent properties, low pour point and favorable viscosity index. Its use results in better fuel economy and less tendency to form deposits.

In addition to the ingredients described above, the inventive Oil-based lubricants also contain other conventional agents, such as antioxidants, metal deactivators, Agents that lower the pouring point, oily agents, exudate agents or peptizers.

The oil-based lubricants according to the invention can be used in conventionally formed. For this purpose. Can

909841/0484

the various constituents are brought together and mixed with one another at a slightly elevated temperature, for example at about 38 to 55 ^° C., to form a uniform composition.

The additives required to form the lubricant according to the invention are occasionally also available in Form of mixtures in mineral oil or other solvent carrier. Refer to the amounts by weight given above Unless otherwise stated, however, in each case on the amount of additional material on carrier or solvent-free basis.

The oil-based lubricants of the invention can be use to lubricate internal combustion engines. The components of such internal combustion engines that require lubrication are taken care of for an amount of a lubricant according to the invention sufficient for lubrication, then result This results in substantial advantages according to the invention. '

The invention is further illustrated by the following examples explained.

Examples 1-4

The following examples demonstrate certain advantages of using an oxidized functional polymer result as a dispersing improver - VI according to the invention.

To prepare a series of four different oil-based lubricants, the individual components shown below are mixed at slightly elevated temperature, namely about 38 till 55 ⁰ C, thoroughly together. To this

909841/0484

-X-

185U65

The following lubricants can be obtained:

Table I.

Examples

Components in% by weight

Mineral oil, 125 SUS
at 38 ⁰ C 84 , 0 - 74.7 67.5 67.5 conventional additives
Mixture ^ ' 7th , 4 7.5 7.5 7.5 (2)
Methacrylate polymer ^v '
functional polymer 8th , 6 7.8 15.0 - (4)
functional polymer - - - 15.0 Graphite dispersion _ 10.0 10.0 10.0

The above mixture (1) is a commercially available combination of materials, each of which is used in lubricants oil-based is conventional. This mixture contains alkyl zinc dithiophosphate, overbased and neutral calcium sulfonates, calcium phosphonate phenate, an ashless dispersant and an ashless rust inhibitor. Next contains this mixture also uses about 50 percent by weight of a light mineral oil as a solvent for the active ingredients.

The methacrylate polymer (2) is a known one for improving the viscosity index of lubricating oil polymers and common polymethacrylate. This polymer contains practically no N-vinylpyrrolidone. It contains about 50 percent by weight of a mineral oil as a solvent for the polymer. The polymer has an average molecular weight

909841/0484

S daily>

185U65

of about 800,000 and is derived from a methacrylic acid ester containing about 16 carbon atoms per molecule.

The functional polymer (3) is a reaction product which is obtained when 500 g of an ethylene-propylene copolymer with a number average molecular weight of 1800 to 2000 are placed in an open reaction vessel and ^{heated to 154 °} C. for 3 hours with vigorous stirring. At the end of 3 hours the oxidation is complete. The oxygen content of the product obtained thereafter is 3.7%.

0.285 mol of the oxidized copolymer obtained above the mixture is then heated while passing in a stream of nitrogen of about 30 liters per hour and adding 49 g (0.258 M) tetraethylene pentamine (TEPA) over a period of 10 minutes. Then with moderately rapid stirring Heating continued for 1 hour, the water formed as a by-product during this time being replaced by nitrogen stream removed from the reaction zone. In this way a product is obtained which contains 1.25% nitrogen (theoretical Amount 1, -25%).

The functional polymer (4) is an amorphous ethylene propylene copolymer which has been prepared by solution polymerization using a Ziegler-Natta catalyst, a vanadium oxytrichloride solution in combination with an ethylaluminum sesquichloride solution. For this purpose, dry n-heptane (1200 ml) is saturated at 30 ° C. and a pressure of 2.11 kg / cm ² with a gas mixture of 50 mol percent ethylene, 35 mol percent propylene and 15 mol percent hydrogen. The gas mixture is introduced at a rate of 100.1 per hour, passed through the heptane and then discharged from the system. When the saturation is complete, the addition of the catalyst components in heptane solution is started. The vanadium oxytrichloride solution (0.370 percent by weight) is introduced into the olefin mixture at a rate of 13 ml per hour, while the ethyl aluminum sesquichloride solution (0.459 percent by weight) is introduced into the olefin mixture

', 909841/04 84

I95H65

Feed rate of 60 ml per hour. The Al / V molar ratio is 8 _r O6. At the beginning of the polymerization, the inflow of propylene and ethylene is adjusted so that the higher activity of the latter is compensated accordingly. The mean weight ratio of propylene to ethylene is 2.3. After 1.25 hours, the polymerization is interrupted by replacing the gas mixture with nitrogen and stopping the addition of catalyst. The reaction mixture obtained is then washed twice with methanol to deactivate and remove the catalyst.

The copolymer obtained in the above manner has a number average molecular weight (M) of 28,000 (determined by vapor phase osmometry), has 159 pendent methyl groups per 1000 chain carbon atoms (determined by IR spectroscopy) and has an inherent viscosity of 2.28 dl per g (measured in decalin at 135 ^° C. using a solution of 0.1 g of polymer in 100 ml of solvent).

A solution of 70 g of the above copolymer in 1000 g of heptane is maintained while blowing nitrogen to remove the heptane to 121 ⁰ C, being added gradually 280 g of mineral oil SAE 5W during the removal of the heptane and the viscous mixture obtained from oil and Copolymer then heated ^{to 221 °} C. with vigorous stirring. At this point, the supply of nitrogen is interrupted so that atmospheric oxygen can diffuse into the reaction vessel. After 0.5 hours, the viscosity of the mixture has decreased due to thermal and oxidative degradation to such an extent that it can be vigorously mixed ^{even at the optimum oxidation temperature of 154 ° C.} The batch is therefore stirred by heating at this temperature for a total of 2.5 hours. In this way, the product obtained is an oil solution of an oxidized copolymer.

909841/0484 '

66.5 g of this oil solution of the oxidized copolymer (20.0% active oxidized copolymer) are added to 900 g of benzene and the resulting solution is heated to 49 ^° C. Solid paraformaldehyde (0.69 g, 0, 52 percent by weight based on the oxidized copolymer) and the mixture obtained is heated to 60 ^° C. for 0.5 hours. Hexamethylenediamine (2.66 g, 2.0 percent by weight based on the oxidized copolymer) is then added and the resulting solution is heated for 3 hours vigorously at reflux temperature of 79 ⁰ C. the hereby resulting functional polymer is then heated under nitrogen sparge for 1 hour at 149 ⁰ C, to thereby remove the benzene used as solvent to.

The graphite dispersion (5) based on mineral oil contains about 10 percent by weight of solid graphite particles with a number average Particle size of about 200 millimicrons. The dispersion also contains about 6% of a nitrogen and methacrylate-containing dispersant, by means of which the dispersion is kept stable. This dispersant is derived from a methacrylic acid ester that contains about 16 carbon atoms per molecule.

The oil-based lubricants according to Examples 1 and 2 are used to lubricate an internal combustion engine, which is run for 192 hours according to a so-called reference test VC. The test used for this is described in Multicylinder Test Sequences for Evaluating Automotive Engine Oils — ASTM Special Technical Publication 315F, American Society for Testing and Materials (1973). This is a recognized method for determining reliable comparative values for the behavior of various oil-based lubricants with regard to sludge and varnish formation in corresponding internal combustion engines under normal working conditions. 909841/0484

285H65

The values for sludge and lacquer formation obtained in the above reference test VC are based on a visual one Observation of various machine components and comparison with a number of CRC reference standards.

The results obtained in the above experiments using the oil-based lubricants described above are shown in Table I below.

Corresponding minimum values are also provided for comparison purposes specified for an SE standard lubricating oil.

Tabel

Reference test VC

Examples

Result

SE minimum values

mean total silting 8.7

8.5

average overall lacquer formation 8.3

Piston skirt 8.3

7.8

8.0

8.0 7.9

From the above experimental data, it appears that lubricants containing solid particles greatly lower the Sludge values and the paint formation values (increase in sludge and paint formation) result. This conclusion will by comparing the results for the lubricant according to Example 2 with the results for the non-graphite one Lubricant according to Example 1 clear. The addition of a conventional agent to improve the viscosity index therefore results in a lubricant without solid

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Particles provide adequate protection against mud and Lacquer formation (see Example 1), however, results in a lubricant to which such solid particles are added for a material that no longer corresponds to the SE qualification standard (example 2).

The reference experiment described in Examples 1 and 2 VC shows the problems encountered in formulating suitable oil-based solids-containing lubricants.

In contrast, Examples 3 and 4 are according to the invention Oil-based lubricants. These lubricants contain graphite and certain defined functional polymers of the specified type, and their use leads to less than lubricants which do not contain such polymers Separation of sludge and paint. The lubricants according to Examples 3 and 4 therefore represent examples according to the invention improved oil-based lubricants containing solids.

Examples 5-8

The following examples demonstrate certain advantages of the present invention Oil-based lubricants that act as dispersing improvers - VI a nitrogen-containing polymer contain,

To prepare a series of four different oil-based lubricants, the individual components shown below are mixed at slightly elevated temperature, namely about 38 till 55 ⁰ C, thoroughly together. In this way you can get the following lubricants:

909841/0484

issues

T a b e 1 1 e III

Components in% by weight

Mineral oil, 125 SUS at 38 ⁰ C

84.0 74.7 75.0 75.0

conventional additives

mixture

(1)

Methacrylate polymer

(2)

7.4 7.5

8.6 7.8

7.5 7.5

nitrogen-containing graft polymer

Interpolymer

(4)

Graphite dispersion

(5)

7.5

7.5

10.0 10.0 10.0

The above mixture (1) is a commercially available combination made of materials each of which is conventional in oil-based lubricants. This mixture contains alkyl zinc dithiophosphate, overbased and neutral calcium sulfonates, calcium phosphonate phenate, an ashless dispersant and an ashless rust inhibitor. Next contains this mixture also includes about 50 percent by weight of a light mineral oil as a solvent for the active ingredients.

The methacrylate polymer (2) is one for improving the viscosity index of lubricating oil polymers known and common polymethacrylate. This polymer contains practically no N-vinyl pyrrolidone. It contains about

909841 / (U 84

'%' issues

50 percent by weight of a mineral oil as a solvent for the polymer. The polymer has an average molecular weight of about 800,000 and is derived from a methacrylic acid ester containing about 16 carbon atoms per molecule.

The nitrogen-containing graft polymer (3) is is a graft polymer produced according to US Pat. No. 3,923,930 with a terpolymer base chain of ethylene, propylene and 4,4-hexadiene in a weight ratio of about 50: 46: 4. This terpolymer has an inner Viscosity of about 1.1, has about 1 mole of unsaturation per 2000 grams of terpolymer, and has about 1500 carbon atoms per terpolymer molecule. N, N-dimethyaminoethyl methacrylate is grafted onto the terpolymer base chain. It will about 2.67 g of this methacrylate was used. The graft polymer contains about 0.04 weight percent nitrogen.

The nitrogen-containing interpolymer (4) has a molecular weight between 30,000 and 120,000, and it is produced by reacting a mixture of C ₁₂ -C ₁ -alkyl methacrylates (Neodol 25L) and C. ₆ -C _2Q -alkyl methacrylates (Alfor 1620 SP) with either dimethylaminoethyl methacrylate or N- (1,1-dimethylbutan-3-one) acrylamide in the following proportions:

Table IV Monomers in% by weight

Dimethylaminoethyl meth-

acrylate 4 - - 5 - 8

N- (1,1-dimethylbutane-3-

on) acrylamide - 4 5 - 8

¹² ~ ^C 16 "alkyl methacrylate

(Neodol 25L) 71 71 70 70 67 67

C ₁ gC _2Q alkyl methacrylate
(Alfol 1620 SP) 25 25 25 25 25 25

909841/0484

10 10 - 70 70 20th 20th

«51465

The respective monomers are mixed with 100 g of a hydrotreated paraffinic base oil having a viscosity of about 145 SUS at 38 ⁰ C combined, introduced into a 1 1 resin kettle and washed 40 hours with purified nitrogen therein. The resulting reaction mixture is then heated to 80 to 83 ⁰ C treated with 0.5 g of azobisisobutyronitrile and 0.3 g of dodecyl mercaptan, the polymerization being allowed to run for 4 hours to completion. Then increasing the temperature of the reaction mixture to 100 ⁰ C and leaves the whole for 1 hour at that temperature, whereupon one then 300 g of a hydrotreated and dewaxed paraffin base oil having a viscosity of about 100 SUS at 38 ⁰ C is added and the temperature ^{holds at 100 0} C for a further hour. In this way one arrives at an interpolymer which is dissolved in oil as a diluent. The amount by weight used is on a diluent-free basis.

The graphite dispersion (5) based on mineral oil contains about 10 percent by weight of solid graphite particles with a number average Particle size of about 200 millimicrons. The dispersion also contains about 6% of a nitrogen and methacrylate-containing dispersant, by which the dispersion is kept stable. This dispersant is derived from a methacrylic acid ester, the contains about 16 carbon atoms per molecule.

The oil-based lubricants according to Examples 5 and are used for the lubrication of an internal combustion engine, which one after a so-called reference test VC Runs 192 hours. The test used for this is in Multicylinder Test Sequences for Evaluating Automotive Engine Oils — ASTM Special Technical Publication 315F / American Society for Testing and Materials (1973)

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described. This is a recognized method for determining reliable comparative values for the behavior of various oil-based lubricants with regard to sludge and varnish formation in the case of corresponding ones Combustion machines under normal working conditions.

The values for sludge and lacquer formation obtained in the above reference test VC are based on a visual one Observation of various machine components and comparison with a number of CRC reference standards.

The results obtained in the above experiments using the oil-based lubricants described above can be found in Table V below.

Corresponding minimum values are also provided for comparison purposes specified for an SE standard lubricating oil.

Table V

Reference test VC

Examples

Result

SE minimum values

mean overall
silting 8.7 8.1 8.5 mean overall lacquer formation 8.3 7.8 8.0 Piston skirt 1 • 8.3 8.0 7.9

909841/0484

-Cl '' 185 U6S

From the above experimental data, it appears that lubricants containing solid particles greatly lower the Sludge values and the paint formation values (increase in sludge and paint formation) result. This conclusion will by comparing the results for the lubricant according to Example 6 with the results for the non-graphite one Lubricant according to Example 5 clear. The addition of a conventional agent to improve the viscosity index therefore gives a lubricant without solid particles sufficient protection against sludge and Lacquer formation (see Example 5), but with a lubricant to which such solid particles are added, for a material that no longer corresponds to the SE qualification standard (example 6).

The reference test VC described in Examples 5 and 6 shows the solids-containing test which is suitable for the formulation Problems encountered with oil-based lubricants.

By contrast, Examples 7 and 8 are oil-based lubricants according to the invention. These contain lubricants Graphite and certain defined functional polymers of the type indicated, and their use leads to lubricants, which do not contain such polymers lead to less sludge and varnish separation. The lubricants according to of Examples 7 and 8 therefore represent examples of improved solid-containing lubricants according to the invention based on oil.

Examples 9-12

The following examples demonstrate certain advantages of the present invention Oil-based lubricants that act as dispersing improvers - VI a nitrogen-containing mixed ester contain.

909841/0484

I85H65

To prepare a series of four different oil-based lubricants, the individual components shown below are mixed at slightly elevated temperature, namely about 38 till 55 ⁰ C, thoroughly together. In this way you can get the following lubricants:

Table VI

Components in% by weight

10

11

Mineral oil, 125 SUS at 38 ⁰ C

84.0 74.7 74.2 74.2

conventional additives

mixture

(1)

Methacrylate polymer

(2)

7.4 7.5

8.6 7.8

7.5 7.5

nitrogenous

(3)

Graft polymer

Interpolymer

(4)

Graphite dispersion

(5)

8.3

8.3

10.0 10.0 10.0

The above mixture (1} is a commercially available combination of materials, each of which is used in lubricants oil-based is conventional. This mixture contains alkyl zinc dithiophosphate, Overbased and neutral calcium sulfonates, calcium phosphonate phenate, an ashless dispersant and an ashless rust inhibitor. This mixture also contains about 50 percent by weight of a light one Mineral oil as a solvent for the active ingredients,

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3851465

The methacrylate polymer (2) is a for Improvement of the viscosity index of lubricating oil polymers known and common polymethacrylate. This polymer contains practically no N-Viny! pyrrolidone. It contains about 50 percent by weight of a mineral oil as a solvent for the polymer. The polymer has an average molecular weight of about 800,000 and is derived from a methacrylic acid ester containing about 16 carbon atoms per molecule.

The nitrogen-containing graft polymer (3) is a styrene-maleic acid interpolymer which has been prepared by forming a solution of styrene (16.3 parts by weight) and maleic anhydride (12.9 parts by weight) in a benzene-toluene solution (270 parts by weight) ( Weight ratio of benzene to toluene 66.5: 33.5) and treatment of this solution for 8 hours at 86 ^° C. under a nitrogen atmosphere with a benzoyl peroxide obtained by dissolving 70% benzoyl peroxide (0.42 parts) in a similar benzene-toluene mixture (2 , 7 parts). In this way, the product obtained is a viscous slurry of the interpolymer in the solvent mixture. A mineral oil (141 parts) is added to this suspension, while the solvent ^{mixture is distilled off first at 150 °} C. and then at 150 ^° C. under a pressure of 200 mm Hg. 209 parts of the resulting stripped slurry of mineral oil and interpolymer (the interpolymer has a reduced specific viscosity of 0.72) is added to toluene (25.2 parts), n-butyl alcohol (4.8 parts), a commercial alcohol from practically primary alcohols having 12 to 18 carbon atoms (55.6 parts) and a commercial alcohol made from primary alcohols having 8 to 10 carbon atoms ¹ (10 parts), and 96 percent sulfuric acid (2.3 parts) is then added to the resulting mixture. The mixture is then heated for 20 hours

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den to 150 to 160 ⁰ C and then distilled off the water. The material obtained is then treated with further sulfuric acid (0.18 parts) together with further n-butyl alcohol (3 parts), whereupon the esterification is continued until 95% of the carboxyl groups present in the polymer have been esterified. The esterified interpolymer obtained in this way is mixed with aminopropylmorpholine (3.71 parts, namely a 10 percent excess over the amount stoichiometrically required to neutralize the remaining free carboxyl groups), whereupon the mixture obtained is used to distill off toluene and other volatile constituents under pressure heated from 10 mm Hg to 150 to 160 ⁰ C. The stripped product is then mixed with more mineral oil (12 parts) and filtered. In this way, a mineral oil solution of the nitrogen-containing mixed ester, which has a nitrogen content of 0.16 to 0.17%, is obtained as the piltrate.

The nitrogen-containing interpolymer (4) is a carboxyl group-containing interpolymer which is prepared by forming a solution of styrene (16.3 parts by weight) and maleic anhydride (12.9 parts by weight) in a mixture of benzene and toluene (270 parts) ( Weight ratio of benzene to toluene 66.5 to 33.5) and 8 hours of treatment of this solution at 86 ⁰ C in a nitrogen atmosphere with a catalyst solution of 70% benzoyl peroxide (0.42 parts by weight) in a similar mixture of benzene and toluene (2 , 7 parts by weight). The product obtained is a viscous slurry of the interpolymer in the solvent mixture. Mineral oil (141 parts by weight) is added to this suspension, while the solvent is ^{distilled off first at 150 °} C. and then at 150 ^° C. and 200 mm Hg. 209 parts by weight of the stripped slurry of mineral oil and interpolymer (the interpolymer has a reduced specific viscosity of 0.72) is mixed with toluene (25.2 wt.

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parts), n-butyl alcohol (4.8 parts by weight), a commercial alcohol consisting essentially of primary alcohols having 12 to 18 carbon atoms (56.6 parts by weight) and a commercial alcohol made from primary alcohols having 8 to 10 carbon atoms (10 parts by weight) and are then 96 percent sulfuric acid (2.3 parts by weight) to the mixture obtained. The reaction mixture is then heated to 150 to 160 ^° C. for 20 hours and the water is then distilled off. Further sulfuric acid (0.18 parts by weight) is then added together with further n-butyl alcohol (3.0 parts by weight) and the esterification is continued until 95% of the carboxyl radicals present in the polymer have been esterified. The esterified interpolymer obtained in this way (400 parts by weight) is then mixed with hydrazine (64 percent strength aqueous solution) (2.7 parts by weight), whereupon the resulting mixture is first heated to 150 ^° C. and then to 150 ^° C. at 100 to distill off volatile constituents mm Hg heated. The stripped product thus obtained is mixed with mineral oil (126 parts by weight) and filtered. The resulting filtrate is a mineral oil solution of the nitrogen-containing ester.

The graphite dispersion (5) based on mineral oil contains about 10 percent by weight of solid graphite particles with a number average Particle size of about 200 millimicrons. The dispersion also contains about 6% of a nitrogen and methacrylate-containing dispersant, by means of which the dispersion is kept stable. This dispersant is derived from a methacrylic acid ester that contains about 16 carbon atoms per molecule.

The oil-based lubricants according to Examples 9 and 10 are used to lubricate an internal combustion engine, which one after a so-called reference test VC Runs 192 hours. The test used for this is in Multicylinder Test Sequences for Evaluating Automotive Engine Oils — ASTM Special Technical Publication 315F, American Society for Testing and Materials (1973)

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5}

described. This is a recognized method for determining reliable comparative values for the behavior of various oil-based lubricants with regard to sludge and varnish formation in the case of corresponding ones Combustion machines under normal working conditions.

The values for sludge and lacquer formation obtained in the above reference test VC are based on a visual one Observation of various machine components and comparison with a number of CRC reference standards.

The results obtained in the above experiments using the oil-based lubricants described above are shown in Table VII below.

Corresponding minimum values are also provided for comparison purposes specified for an SE standard lubricating oil.

Table VII

Reference test VC

Examples

Result

10

SE minimum values

mean total silting 8.7

8, f

8.5

mean overall
lacquer formation 8th , 3 7.8 8th , 0 Piston skirt 8th , 3 8.0 7th , 9

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The above test values show that lubricants,

which contain solid particles result in a strong reduction in the sludge values and the lacquer formation values (increase in sludge and lacquer formation). This conclusion will
by comparing the results for the lubricant according to Example 10 with the results for the non-graphite-containing lubricant according to Example 9. The addition
a conventional viscosity index improving agent therefore gives a non-solid lubricant
Particles provide adequate protection against sludge and varnish formation (see Example 9), but leads to one
Lubricant to which such solid particles are added to a material which no longer meets the SE qualification standard (Example 10).

The reference test described in Examples 9 and 10 VC shows the problems encountered in formulating suitable oil-based solids-containing lubricants.

In contrast, Examples 11 and 12 are oil-based lubricants according to the invention. These contain lubricants
Graphite and certain defined functional polymers of the specified Ar, t ^ and their use leads to less sludge and varnish deposition compared to lubricants which do not contain such polymers. The lubricants according to Examples 11 and 12 therefore represent examples of improved lubricants containing solids according to the invention
based on oil.

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Claims (27)

-X- claims 1. Oil-based lubricant from a larger amount by weight an oil with lubricating viscosity, a lower weight amount of solid particles to improve the Lubricating properties of this agent and a smaller amount by weight of a dispersing improver -VI, thereby characterized in that this dispersing improver - VI is one of the following Substances are: (a) a functional polymer in the form of a reaction product from (i) an oxidized higher molecular weight amorphous copolymer of essentially ethylene and propylene with a number average molecular weight of at least about 20,000 and with at least 140 out-of-chain methyl groups in 1,000 Chain carbon atoms and from (ix) an aliphatic Amine or polyamine, (b) a graft polymer in which on a olefin polymer backbone a dxalkylamxnoalkyl methacrylate is grafted, (c) an interpolymer of a long chain n-alkyl methacrylate and a dialkylamine alkyl methacrylate or an N- (alkanone) acrylamide and / or (d) a nitrogen-containing ester of a carboxyl group-containing one Interpolymers, which consists of alpha, ß-unsaturated acids or acid anhydrides and olefins, a has reduced specific viscosity of about 0.05 to about 2 dl / g, carboxylic acid ester groups from at least Contains 8 carbon atoms and furthermore via carbony! Amino groups disposes. 909841/0484 I85U65 2. Lubricant according to claim 1, characterized characterized in that a predominant proportion of the solid particles have a maximum transverse dimension of about 1 millimicron to 2 microns. 3. Lubricant according to claim 2, characterized characterized in that the solid particles are graphite, molybdenum disulfide, zinc oxide or mixtures thereof and are present in an amount of about 0.5 to 5 percent by weight, based on the total agent, and the dispersion improver - VI in an amount of about 0.1 to percent by weight, based on the total agent is. 4. Lubricant according to claim 3, characterized in that the dispersion improver - VI is a functional polymer from a reaction product of '(1) an oxidized higher molecular weight amorphous copolymer of essentially ethylene and propylene having a number average molecular weight of at least about 20,000 and with at least 140 pending methyl groups per 1,000 chain carbon atoms and from (2) an aliphatic Amine or polyamine, and that this polymer in one for a reduction in the formation of deposits effective amount is present in that lubricant. 5. Lubricant according to claim 4, characterized in that the oxidized copolymer has a molecular weight of about 20,000 to 200,000. 909841/0484 -yi- issues 6. Lubricant according to claim 5, characterized in that the aliphatic amine is a primary or secondary aliphatic amine or diamine of the general formula H "N (CH _? ) NH ₂ , wherein y is 3 to 10, these amines or diamines up to contain about 10 carbon atoms in the alkyl group, or a polyalkylene polyamine of the general formula HN- (AN) H, I ^X is where A is a divalent alkylene radical with about 2 to 6 carbon atoms means and χ stands for 1 to about 10. 7. Lubricant according to claim 18, characterized in that the functional polymer is produced by the simultaneous reaction of an oxidized copolymer of practically ethylene and propylene with an aliphatic amine or polyamine at a temperature of about 60 to 177 ⁰ C and recovery of the reaction product obtained, wherein the reactants are used in a molar ratio of about 1: 2 to 1:20. 8. The method according to claim 7, characterized in that the functional polymer has a number average molecular weight of about 25,000 to 40,000. 909841/0484 l / 1Θ5Η65 9. Lubricant according to claim 1, characterized in that the functional polymer has been prepared by reactants (1) and (2) furthermore with a formaldehyde-forming Reactants converts. 10. Lubricant according to claim 6, characterized in that the functional polymer has been prepared by simultaneous reaction of an oxidized copolymer of ethylene and propylene, a formaldehyde-forming reactant and an aliphatic amine or polyamine at about 121 to 137 ⁰ C and recovery of the resulting reaction product using the reactants in a molar ratio of 1: 2: 2 to about 1:20:20. 11. Lubricant according to claim 3, characterized characterized in that the dispersing improver -VI used is a graft polymer in which a dialkylaminoalkyl methacrylate on an olefin polymer backbone is grafted. 12. Lubricant according to claim 11, characterized characterized in that the graft polymer consists of an oil-soluble, practically linear hydrocarbon-like Polymer backbone consists of ethylene, which has at least one terminal saturated straight-chain alkene having 3 to about 12 carbon atoms and at least a terminal unsaturated non-conjugated diolefin with 5 to about 8 carbon atoms, the basic chain of which has an average chain length of about 700 to Has 7000 carbon atoms and on which a monomer of a dialkylaminoalkyl methacrylate is repeated of the formula 909841/0484 Il CH ₀ = CCOA-N ' CH ₃ \ R 1 2 R ¹ and R ^{1 are} alkyl having 1 or 2 carbon atoms and A for a divalent alkylene radical with 2 up to about 4 carbon atoms, or a mixture thereof is grafted on. 13. Lubricant according to claim 12, characterized in that the graft polymer has an inherent viscosity of about 0.6 to 1.9 in the form of a 0.10 weight ^{percent solution in tetrachlorethylene at 30 0} C and a weight ratio of backbone component to graft component of approximately
1000: 1 to about 1:10. 14. Lubricant according to claim 12, characterized in that about 15 to 75 percent by weight of the basic chain consist of ethylene, with about 25 to 85 percent by weight of the basic chain being straight-chain alkene, and about 0.10 to 15 percent by weight of the
Base chain consist of diolefin. 909841/0484 aesuss 15. Lubricant according to claim 3, characterized characterized in that the dispersing improver - VI is an interpolymer of a long-chain n-alkyl methacrylate and a dialkyl aminoalkyl methacrylate or N- (alkanone) acrylamide. 16. Lubricant according to claim 15, characterized characterized in that the monomeric N-alkyl methacrylate has about 12 to 18 carbon atoms in the aliphatic Includes chain. 17. Lubricant according to claim 16, characterized characterized in that the dialkylaminoalkyl methacrylate is a di-C ^ -C -.-alkylamino-C.-Cg-alkyl methacrylate is. 18. Lubricant according to claim 17, characterized in that the dialkylaminomethacrylate is a dimethylaminoethyl methacrylate. 19. Lubricant according to claim 15, characterized in that the acrylamide is an N- (C ₄ -C ₁ "alkane) acrylamide. 20. Lubricant according to claim 3, characterized in that the dispersion improver * - VI a carboxyl group-containing interpolymer made from alpha, ß-unsaturated acids or acid anhydrides 909841/0484 -κ- and olefins having a reduced specific viscosity of about 0.05 to 2, their carboxyl groups Are carboxylic acid ester groups having at least 8 carbon atoms, with carbonylamino groups. 21. Lubricant according to claim 20, characterized characterized in that the nitrogen-containing ester of the carboxyl group-containing interpolymer Mixed ester of a carboxyl group-containing interpolymer which has practically no titratable acidity and contains in its polymer structure at least one of each of the following three pendent polar groups: (A) A relatively high molecular weight carboxylic acid ester group with at least 8 aliphatic carbon atoms in the ester residue, (B) a relatively low molecular weight carboxylic acid ester group having not more than 7 aliphatic carbon atoms in the ester residue, (C) a carbonyl polyamino group derived from a polyamino compound is derived with a primary or secondary amino group, wherein the molar ratio of (A) to (B) to (C) is about (60-90) :( 10-30) :( 2-15). 22. Lubricant according to claim 21, characterized in that the carbonyl polyamino group of a polyamino compound with a primary or secondary amino group with at least one monofunctional amino group. 909841/0484 23. Lubricant according to claim 22, characterized characterized in that the monofunctional amino group is a tertiary amino group or a heterocyclic Is amino group. 24. Lubricant according to claim 23, characterized in that the amino group of Aminoethylmorpholxn or aminopropylmorpholine derived. 25. Lubricant according to claim 21, characterized in that the carbonyl polyamino groups derived from hydrazine or hydrocarbon-substituted hydrazine. 26. Lubricant according to claim 21, characterized in that the interpolymer is a Interpolymer of styrene and maleic acid or maleic anhydride. ■, 27. Lubricant according to claim 21, characterized in that the interpolymer is a has reduced specific viscosity of about 0.3 to 1. 909841/0484