BACKGROUND OF THE INVENTION 1. Field of the Invention

Numerous deposit-forming substances are inherent in hydro- carbon fuels. These substances when used in internal combustion engines tend to form deposits on and around constricted areas of the engine contacted by the fuel. Typical areas commonly and sometimes seriously burdened by the formation of deposits include carburetor ports, the throttle body and venturies, engine intake valves, etc.

Deposits adversely affect the operation of the vehicle. For example, deposits on the carburetor throttle body and ven- turies increase the fuel to air ratio of the gas mixture to the combustion chamber thereby increasing the amount of unburned hydrocarbon and carbon monoxide discharged from the chamber. The high fuel-air ratio also reduces the gas mileage obtainable from the vehicle.

Deposits on the engine intake valves when they get suffi- ciently heavy, on the other hand, restrict the gas mixture flow into the combustion chamber. This restriction, starves the engine of air and fuel and results in a loss of power. Deposits on the valves also increase the probability of valve failure due to burning and improper valve seating. In addition, these deposits may break off and enter the com- bustion chamber possibly resulting in mechanical damage to the piston, piston rings, engine head, etc.

The formation of these deposits can be inhibited as well as removed by incorporating an active detergent into the fuel. These detergents function to cleanse these deposit-prone areas of the harmful deposits, thereby enhancing engine per- formance and longevity. There are numerous detergent-type gasoline additives currently available which, to varying degrees, perform these functions.

Two factors complicate the use of such detergent-type gasoline additives. First, with regard to automobile engines that require the use of nonleaded gasolines (to prevent disablement of catalytic converters used to reduce emissions), it has been found difficult to provide gasoline of high enough octane to prevent knocking and the con- comitant damage which it causes. The chief problem lies in the area of the degree of octane requirement increase, herein called "ORI", which is caused by deposits formed by the commercial gasoline.

The basis of the ORI problem is as follows: each engine, when new, requires a certain minimum octane fuel in order to operate satisfactorily without pinging and/or knocking. As the engine is operated on any gasoline, this minimum octane increases and, in most cases, if the engine is operated on the same fuel for a prolonged period, will reach an equilibrium. This is apparently caused by an amount of deposits in the combustion chamber. Equilibrium is typi- cally reached after 5,000 to 15,000 miles of automobile operation.

The octane requirement increase in particular engines used with commercial gasolines will vary at equilibrium from 5 to 6 octane units to as high as 12 or 15 units, depending upon

the gasoline compositions, engine design and type of opera- tion. The seriousness of the problem is thus apparent. A typical automobile with a research octane requirement of 85, when new, may after a few months of operation require 97 research octane gasoline for proper operation, and little unleaded gasoline of that octane is available. The ORI problem also exists in some degree with engines operated on leaded fuels. U.S. Patent Nos. 3,144,311; 3,146,203; and 4,247,301 disclose lead-containing fuel compositions having reduced ORI properties.

The ORI problem is compounded by the fact that the most common method for increasing the octane rating of unleaded gasoline is to increase its aromatic content. This, how- ever, eventually causes an even greater increase in the octane requirement. Moreover, some of presently used nitrogen-containing compounds used as depositcontrol addi- tives and their mineral oil or polymer carriers may also significantly contribute to ORI in engines using unleaded fuels.

It is, therefore, particularly desirable to provide deposit control additives which effectively control the deposits in intake systems of engines, without themselves eventually contributing to the problem.

In this regard, hydrocarbyl poly(oxyalkylene) aminocarba- mates are commercially successful fuel additives which control combustion chamber deposits thus minimizing ORI.

The second complicating factor relates to the lubricating oil compatibility of the fuel additive. Fuel additives, due to their higher boiling point over gasoline itself, tend to accumulate on surfaces in the combustion chamber of the

engine. This accumulation of the additive eventually finds its way into the lubricating oil in the crankcase of the engine via a "blow-by" process and/or via cylinder wall/piston ring "wipe down". In some cases, as much as 25%-30% of the nonvolatile fuel components, i.e., including fuel additives, will eventually accumulate in the lubri- eating oil. Insofar as the recommended drain interval for some engines may be as much as 7,500 miles or more, such fuel additives can accumulate during this interval to sub- stantial quantities in the lubricating oil. In the case where the fuel additive is not sufficiently lubricating oil compatible, the accumulation of such an oil-incompatible fuel additive may actually contribute to crankcase deposits, i.e., varnish and sludge, as measured by a Sequence V-D test.

The incompatibility of certain fuel additives in lubricating oils, i.e., oils which contain other additives, arises in spite of the fact that some fuel additives are also known to be lubricating oil dispersants.

Several theories exist as to the cause of the lubricating oil incompatibility of certain fuel additives. Without being limited to any theory, it is possible that some of these fuel additives when found in the lubricating oil interfere with other additives contained in the lubricating oil and either counterbalance the effectiveness of these additives or actually cause dissolution of one or more of these additives including possibly the fuel additive itself. In either case, the incompatibility of the fuel additive with other additives in the lubricating oil demonstrates itself in less than desirable crankcase deposits as measured by Sequence V-D engine tests.

in another theory, it is possible that the accumulation of the fuel additive into the lubricating oil during the drain interval period surpasses its maximum solubility in the lubricating oil. In this theory, this excess amount of fuel additive is insoluble in the lubricating oil and is what causes increased crankcase deposits.

In still another theory, it is possible that the fuel addi- tive will decompose in the lubricating oil during engine operation and the decomposition products are what cause increased crankcase deposits.

in any case, lubricating oil incompatible fuel additives are less than desirable insofar as their use during engine operation will result in increased deposits in the crank- case. This problem can be severe. Accordingly, it would be particularly advantageous to develop a good deposit control fuel additive which does not contribute to ORI and which additionally possesses lubricating oil compatibility.

The instant invention is directed to fuel compositions con- taining a novel class of alkylphenyl poly(oxyalkylene) aminocarbamates which as a fuel additive controls combustion chamber deposits thus minimizing ORI and in lubricating oil have improved compatibility in the lubricating oil composi- tion. The novel additives of this invention are very long chain alkylphenyl poly(oxyalkylene) aminocarbamates having a molecular weight of about 800 to 6,000 wherein the alkyl group of said alkylphenyl group contains at least 40 carbon atoms.

This invention is also directed toward dispersants compat- ible in lubricating oil. In particular, this invention is directed toward disperεant additives possessing improved

compatibility in lubricating oil which are alkylphenyl poly(oxyalkylene) aminocarbamates having at least one basic nitrogen and wherein the alkyl group of said alkylphenyl poly(oxyalkylene) aminocarbamate contains at least 40 carbon atoms.

The incompatibility of certain dispersant additives in lubricating oil, i.e., oils which contain other additives, is recognized in the art and arises in spite of the fact that certain of these additives are known lubricating oil dispersants.

Several theories exist as to the cause of the lubricating oil incompatibility of certain additives. Without being limited to any theory, it is possible that some of these additives interfere with other additives contained in the lubricating oil and either counterbalance the effectiveness of these additives Or actually cause dissolution of one or more of these additives, including possibly the dispersant additive itself.

In another theory, it is possible that the additive will decompose in the lubricating during engine operation and the decomposition products are what cause increased crankcase deposits.

In still another theory, it is also possible that the incompatibility of the additive is related to its oil solubility.

Lubricating oil incompatible additives are less than deεir- able insofar as their use during engine operation will result in increased crankcase deposits, i.e., varnish and

sludge, in the crankcase as measured by Sequence V-D engine tests. This problem can be severe.

The instant invention is directed to a novel class of very long chain alkylphenyl poly(oxyalkylene) aminocarbamates which provide improved compatibility in lubricating oil compositions. The novel additives of this invention are alkylphenyl poly(oxyalkylene) aminocarbamates having a molecular weight of about 800 to 6,000 wherein the alkyl group of said alkylphenyl poly(oxyalkylene) aminocarbamate contains at least 40 carbon atoms.

2. Prior Art

Numerous references disclose C. to C ₃₀ hydrocarbyl poly(oxy- alkylene) aminocarbamates as fuel additives. These include the following U.S. Patents Nos.:

4,160,648 4,243,798 4,521,610; and 4,191,537 4,270,930 4,568,358. 4,197,409 4,274,837 4,236,020 4,288,612

Of particular relevance is U.S. Patent No. 4,274,837 which discloses that hydrocarbyl poly(oxyalkylene) aminocarbamates containing certain poly(oxyalkylene) chains, i.e., oxypro¬ pylene, when used in fuels employed in combination with certain lubricating oils, produce crankcase varnish. This reference further discloses that lubricating oil compatible hydrocarbyl poly(oxypropylene) aminocarbamates are improved by employing the poly(oxypropylene) as a copolymer having 1 to 5 C _g to C ₃₀ oxyalkylene units.

U.S. Patent No. 4,160,648 discloses an intake system deposit control additive for fuels which is a hydrocarbyl poly(oxy- alkylene) aminocarbamate wherein the hydrocarbyl group is from 1 to 30 carbon atoms including alkyl or alkylphenyl groups. Specifically disclosed hydrocarbyl groups include tetrapropenylphenyl, olelyl and a mixture of . _g , C, _g and c _2n alkyl groups. Likewise, U.S. Patent No. 4,288,612 discloses deposit control additives for gasoline engines which are hydrocarbyl poly(oxyalkylene) aminocarbamates wherein the hydrocarbyl group contains from 1 to about 30 carbon atoms including alkylphenyl groups wherein the alkyl group is straight or branched chain of from 1 to about 24 carbon atoms. U.S. Patent No. 4,568,358 discloses diesel fuel compositions containing an additive such as a hydro- carbyl poly(oxyalkylene) aminocarbamate. This reference discloses hydrocarbyl groups such as alkyl groups of 1 to 30 carbon atoms; aryl groups of 6 to 30 carbon atoms, alkaryl groups of 7 to 30 carbon atoms, etc.

U.S. Patent No. 4,332,595 discloses hydrocarbyl poly(oxy- alkylene) polyamines wherein the hydrocarbyl group is a hydrocarbyl radical of 8 to 18 carbon atoms derived from linear primary alcohols.

U.S. Patent Nos. 4,233,168 and 4,329,240 among others disclose lubricating oil compositions containing a dispersant amount of a hydrocarbyl poly(oxyalkylene) aminocarbamate.

While these prior art references disclose fuel compositions containing C. to C _3Q hydrocarbyl poly(oxyalkylene) amino- carbamates, none of these references disclose the unique alkylphenyl group of this invention nor do any of these references suggest that use of this unique alkylphenyl group

would provide improved compatibility in lubricating oil compositions.

SUMMARY OF THE INVENTION

The instant invention is directed toward a novel class of alkylphenyl poly(oxyalkylene) aminocarbamates which possess improved compatibility with lubricating oil compositions. In particular, the instant invention is directed toward an alkylphenyl poly(oxyalkylene) aminocarbamate having at least one basic nitrogen and an average molecular weight of about 800 to 6,000 and wherein the alkyl group of said alkylphenyl poly(oxyalkylene) aminocarbamate contains at least 40 carbon atoms and the poly(oxyalkylene) polymer is derived from 0- to Cς oxyalkylene units with the proviso that if the poly(oxyalkylene) polymer is a homopolymer of oxyethylene then the poly(oxyethylene) polymer does not contain more than 25 oxyethylene units. The instant invention is based on the discovery that use of the unique alkylphenyl group, i.e., an alkylphenyl group wherein the alkyl group contains at least 40 carbon atoms, imparts to the alkylphenyl poly- (oxyalkylene) aminocarbamate improved lubricating oil compatibility.

The compounds of this invention are useful dispersants in lubricating oil. Thus, in its composition aspect, the instant invention is directed toward a lubricating oil composition comprising an oil of lubricating viscosity and a dispersant effective amount of an alkylphenyl poly(oxy- alkylene) aminocarbamate of this invention.

The instant invention is also directed toward a fuel compo- sition containing a novel class of alkylphenyl poly- (oxyalkylene) aminocarbamates which as a fuel additive

lυ

controls combustion chamber deposits thus minimizing ORI and in lubricating oil provide improved compatibility with the lubricating oil composition. In particular, the instant invention is directed toward a fuel composition comprising a hydrocarbon boiling in the gasoline or diesel range and from about 30 to about 5,000 parts per million of a fuel soluble alkylphenyl poly(oxyalkylene) aminocarbamate having at least one basic nitrogen and an average molecular weight of about 800 to 6,000 and wherein the alkyl group of said alkylphenyl poly(oxyalkylene) aminocarbamate contains at least 40 carbon atoms and the poly(oxyalkylene) polymer is derived from 0- to C- oxyalkylene units with the proviso that if the poly(oxyalkylene) polymer is a homopolymer of oxyethylene then the poly(oxyethylene) polymer does not contain more than 25 oxyethylene units. The instant invention is based on the discovery that use of the unique alkylphenyl group, i.e., an alkylphenyl group wherein the alkyl group contains at least 40 carbon atoms, imparts to the alkylphenyl poly(oxyalkylene) aminocarbamate improved lubricating oil compatibility without contributing to ORI.

DETAILED DESCRIPTION OF THE INVENTION

The alkylphenyl poly(oxyalkylene) aminocarbamates of the present invention consist of an amino moiety and an alkylphenyl poly(oxyalkylene) polymer bonded through a carbamate linkage, i.e., -OC(0)N<. The specific alkylphenyl group employed in the instant invention in the alkylphenyl poly(oxyalkylene) polymer is critical to achieving improved lubricating oil compatibility for the alkylphenyl poly(oxy- alkylene) aminocarbamates. In particular, it has been found that employing the alkylphenyl group of this invention wherein the alkyl group contains at least 40 carbon atoms

results in an alkylphenyl poly(oxyalkylene) aminocarbamate which has improved lubricating oil compatibility.

The Preferred Alkylphenyl Group

The preferred alkylphenyl group of the alkylphenyl poly(oxyalkylene) aminocarbamate employed in this invention is derived from the corresponding alkylphenol of Formula I below:

OH

wherein R is an alkyl group of at least 40 carbon atoms and m is an integer from 1 to 2.

Preferably, m is one.

Preferably R is an alkyl group of from 50 to 200 carbon atoms. More preferably, R is an alkyl group of from 60 to 100 carbon atoms.

When m is one, the alkylphenyl is a monoalkylphenyl; whereas when m is two, the alkylphenyl is a dialkylphenyl.

The alkylphenols of Formula I above are prepared by reacting the appropriate olefin or olefin mixture with phenol in the presence of an alkylating catalyst at a temperature of from about 60°C to 200°C, and preferably 125°C to 180°C either neat or in an essentially inert solvent at atmospheric pressure. Preferred alkylating catalysts are a sulfonic acid catalyst such as A berlyεt 19^available from Rohm and

Haas, Philadelphia, Pennsylvania, or boron trifluoride (or an etherate of boron trifluoride). Molar ratios of reac- tants can be employed. When molar ratios are employed, the reaction yields a mixture of dialkylphenol, monoalkylphenol and unreacted phenol. As noted above, dialkylphenol and monoalkylphenol can be used to prepare the additives used in the compositions of this invention whereas the unreacted phenol is preferably removed from the post reaction mixture via conventional techniques. Alternatively, molar excess of phenol can be employed, i.e., 2 to 2.5 equivalents of phenol for each equivalent of olefin with unreacted phenol recycled. The latter process maximizes monoalkylphenol. Examples of inert solvents include benzene, toluene, chloro- benzene and 250 thinner which is a mixture of aromatics, paraffins and naphthenes.

Particularly preferred alkylphenols employed in this invention are monoalkylphenols represented by Formula II below:

wherein R is as defined above.

A particularly preferred class of olefins for use in preparing alkylphenols useful in this invention are polyolefin polymers. Polyolefin polymers are polymers comprising a major amount of C ₃ to C- monoolefin, e.g., ethylene, propylene, butylene, isobutylene and pentene. The polymers can be homopolymers such as polyisobutylene

as well as copolymers of two or more such olefins such as copolymers of: ethylene and propylene, butylene, and isobutylene, etc. Other copolymers include those in which a minor amount of the copolymer monomers, e.g., 1 to 20 mole percent is a C. to Cg nonconjugated diolefin, e.g., a copolymer of isobutylene and butadiene or a copolymer of ethylene, propylene and 1, -hexadiene, etc.

The polyolefin pdlymer usually contains at least 40 carbon atoms, although preferably 50 to 200 carbon atoms and more preferably 60 to 100 carbon atoms.

A particularly preferred class of olefin polymers com- prises the polybuteneε, which are prepared by polymer- ization of one or more of 1-butene, 2-butene and isobutene. Especially desirable are polybutenes con- taining a substantial proportion of units derived from isobutene. The polybutene may contain minor amounts of butadiene which may or may not be incorporated in the polymer. Most often the isobutene units constitute 80%, preferably at least 90%, of the units in the polymer. These polybutenes are readily available commercial irtate- rials well known to those skilled in the art. Disclosures thereof will be found, for example, in U.S. Patents Noε. 3,215,707; 3,231,587; 3,515,669; and 3,579,450, as well as U.S. Patent No. 3,912,764. The above are incorpo- rated by reference for their disclosures of suitable polybuteneε.

In addition to the reaction of a polyolefin with phenol, many other alkylating hydrocarbons may likewise be used with phenol to produce alkylphenol. Other suitable alkyl- ating hydrocarbons include cyclic, linear, branched and internal or alpha olefins having molecular weights of at

least about 560. For example, alpha olefins obtained from the ethylene growth proceεε giveε even number carbon ole- finε. Another source of olefins is by the dimerization of alpha olefins over an appropriate catalyεt such as the well-known Ziegler catalyst. Internal olefins are easily obtained by the isomerization of alpha olefins over a suitable catalyst such aε silica.

Preferred Poly(oxyalkylene) Component

The alkylphenyl poly(oxyalkylene) polymers which are utilized in preparing the carbamates of the present inven- tion are monohydroxy compounds, i.e., alcohols, often termed alkylphenyl "capped" poly(oxyalkylene) glycols and are to be distinguished from the poly(oxyalkylene) glycols (diols), which are not alkylphenyl terminated, i.e., not capped. The alkylphenyl poly(oxyalkylene) alcohols are produced by the addition of lower alkylene oxideε, such aε ethylene oxide, propylene oxide, the butylene oxides, or the pentylene oxides to the alkylphenol of Formula I, i.e. ,

OH

under polymerization conditions, wherein R and m are aε defined above. Preferred poly(oxyalkylene) polymers are those derived from C~ to C . oxyalkylene units; more prefer- ably C ₃ oxypropylene units. Methods of production and properties of these polymerε are diεcloεed in U.S. Patent Noε. 2,841,479 and 2,782,240 and Kirk-Othmer's "Encyclopedia

of Chemical Technology", Volume 19, p. 507. In the polymer- ization reaction, a single type of alkylene oxide may be employed, e.g., propylene oxide, in which case the product is a homopolymer, e.g., a poly(oxypropylene) propanol. However, copolymers are equally satiεfactory and random copolymerε are readily prepared by contacting the hydroxyl- -containing compound with a mixture of alkylene oxides, such aε a mixture of propylene and butylene oxides. Block copolymers of oxyalkylene units also provide satisfactory poly(oxyalkylene) polymers for the practice of the present invention.

Homopolymers of poly(oxyethylene) polymers are much more hydrophilic than homopolymers of C ₃ -Ce poly(oxyalkylene) polymers. Accordingly, when homopolymers of poly(oxy- ethylene) polymers are employed, the amount of poly(oxy- ethylene) must be limited so aε to ensure fuel dispersency/detergency and lubricating oil compatibility of the final carbamate. In general, this is accomplished by limiting the poly(oxyethylene) polymer to about 25 oxy- ethylene units or less; although preferably about 10 oxy- ethylene units or less; and most preferably about 5 oxyethylene units or leεε.

Likewise, copolymers containing a mixture of oxyethylene units and C ₃ -C _ς oxyalkylene units are formulated to ensure that the copolymer poεεesεeε fuel solubility and lubricating oil compatibility.

In general, the poly(oxyalkylene) polymers are mixtures of compounds that differ in polymer chain length. However, their properties closely approximate those of the polymer represented by the average composition and molecular weight.

In general, the very long chain alkylphenyl terminating group on the alkylphenyl poly(oxyalkylene) aminocarbamateε of thiε invention allow for uεe of leεε oxyalkylene unitε in the poly(oxyalkylene) polymer to enεure fuel disperεancy/- detergency εolubility and lubricating oil compatibility than are neceεεary in prior art. carbamate fuel additiveε. Accor- dingly, while longer poly(oxyalkylene) polymerε are func- tional in thiε invention, εuch longer polymerε are not necesεary. Therefore, each poly(oxyalkylene) polymer utilized in thiε invention containε at leaεt 1 oxyalkylene unit, preferably from 1 to about 100 oxyalkylene unitε, more preferably from about 1 to about 25 oxyalkylene unitε, even more preferably from about 1 to about 10 oxyalkylene unitε, and moεt preferably about 5 oxyalkylene unitε or lesε. It iε underεtood that if the poly(oxyalkylene) polymer iε a homopolymer of poly(oxyethylene) , the polymer length is governed by the conεtraintε diεcuεεed above.

An alternative method for preparing alkylphenyl poly(oxy- alkylene) polymerε having 1, 2 or 3 oxyalkylene unitε involves employing a compound of Formula III below:

wherein q iε an integer from 1 to 3 and R, iε hydrogen or a C. to C ₃ alkyl group. When employing the compound of Formula III, the phenoxide of the alkylphenol, I, is first prepared and then reacted with the compound of Formula III to yield the deεired alkylphenol poly(oxyalkylene) polymer having from 1 to 3 oxyalkylene unitε. Compounds of Formula III are either commercially available or can be prepared by art recognized methods.

Preferred Amine Component

The amine moiety of the alkylphenyl poly(oxyalkylene) aminocarbamate employed in thiε invention iε preferably derived from a polyamine having from 2 to about 12 amine nitrogen atomε and from 2 to about 40 carbon atomε. The polyamine is preferably reacted with an alkylphenyl poly- (oxyalkylene) chloroformate to produce the alkylphenyl poly(oxyalkylene) aminocarbamate additives finding use within the scope of the present invention. The chloro- formate iε itεelf derived from alkylphenyl poly(oxy- alkylene) alcohol by reaction with phoεgene. The polyamine, encompaεsing diamines, provideε the product alkylphenyl poly(oxyalkylene) aminocarbamate with, on average, at leaεt about one basic nitrogen atom per carbamate molecule, i.e., a nitrogen atom titratable by a strong acid. The polyamine preferably haε a carbon-to- nitrogen ratio of from about 1:1 to about 10:1.

The polyamine may be substituted with subεtituentε εelected from (A) hydrogen, (B) hydrocarbyl groups of from l to about 10 carbon atomε, (C) acyl groups of from 2 to about 10 carbon atoms, and (D) monoketo, monohydroxy, mononitro, monocyano, lower alkyl and lower alkoxy derivatives of (B) and (C). "Lower", as used in terms like lower alkyl or lower alkoxy, meanε a group containing from 1 to about 6 carbon atomε. At leaεt one of the εubstituents on one of the baεic nitrogen atomε of the polyamine iε hydrogen, e.g., at leaεt one of the baεic nitrogen atomε of the polyamine iε a primary or secondary amino nitrogen atom.

Hydrocarbyl, as used in describing all the components of this invention, denotes an organic radical composed of

carbon and hydrogen which may be aliphatic, alicyclic, aromatic or combinationε thereof, e.g., aralkyl. Prefer- ably, the hydrocarbyl group will be relatively free of aliphatic unsaturation, i.e., ethylene and acetylenic, particularly acetylenic unεaturation. The εubstituted polyamines of the present invention are generally, but not necessarily, N-subεtituted polyamineε. Exemplary hydro- carbyl groupε and subεtituted hydrocarbyl groups include alkyls such as methyl, ethyl, propyl, butyl, isobutyl, pentyl, hexyl, octyl, etc., alkenyls such as propenyl, isobutenyl, hexenyl, octenyl, etc., hydroxyalkyls, such aε 2-hydroxyethyl, 3-hydroxypropyl, hydroxyisopropyl, 4-hydroxybutyl, etc., ketoalkyls, εuch aε 2-ketopropyl, 6-ketooctyl, etc., alkoxy and lower alkenoxy alkylε, such as ethoxyethyl, ethoxypropyl, propoxyethyl, propoxypropyl, 2-(2-ethoxyethoxy)ethyl, 2-(2-(2-ethoxyethoxy)ethoxy)- ethyl, 3,6,9,12-tetraoxatetradecyl, 2-(2-ethoxyethoxy)- hexyl, etc. The acyl groups of the aforementioned (C) subεtituentε are such as propionyl, acetyl, etc. The more preferred substituents are hydrogen, C,-C, alkyls and C,-C. hydroxyalkyls.

In a substituted polyamine the εubεtituentε are found at any atom capable of receiving them. The substituted atoms, e.g., εubstituted nitrogen atomε, are generally geometrically inequivalent, and conεequently the sub- stituted amines finding use in the present invention can be mixtures of mono- and poly-subεtituted polyamineε with substituent groupε εituated at equivalent and/or inequivalent atomε.

The more preferred polyamine finding uεe within the εcope of the present invention iε a polyalkylene polyamine, including alkylene diamine, and including εubεtituted

polyamines, e.g., alkyl and hydroxyalkylsubstituted poly- alkylene polyamine. Preferably, the alkylene group con- tainε from 2 to 6 carbon atoms, there being preferably from 2 to 3 carbon atomε between the nitrogen atomε. Such groupε are exemplified by ethylene, 1,2-propylene, 2,2-di- methylpropylene trimethylene, 1,3,2-hydroxypropylene, etc. Exampleε of such polyamines include ethylene diamine, diethylene triamine, di(trimethylene)triamine, dipropylene triamine, triethylene tetramine, tripropylene tetramine, tetraethylene pentamine, and pentaethylene hexamine. Such amines encompaεε isomerε εuch as branchedchain polyamines and the previously mentioned substituted polyamines, including hydroxy- and hydrocarbylsubstituted polyamines. Among the polyalkylene polyamineε, those containing 2-12 amine nitrogen atoms and 2-24 carbon atoms are especially preferred, e.g., ethylene diamine, propylene diamine, butylene diamine, pentylene diamine, hexylene diamine, diethylene triamine, dipropylene triamine, and the C ₂ -C ₃ alkylene polyamines are most preferred, in particular, the lower polyalkylene polyamines, e.g., ethylene diamine, diethylene triamine, propylene diamine, dipropylene triamine, etc.

The amine component of the alkylphenyl poly(oxyalkylene) aminocarbamate also may be derived from heterocyclic polyamineε, heterocyclic substituted amines and subεti- tuted heterocyclic compounds, wherein the heterocycle compriseε one or more 5-6 membered rings containing oxygen and/or nitrogen. Such heterocycleε may be εaturated or unsaturated and εubεtituted with groups selected from the aforementioned (A), (B), (C) and (D). The heterocycleε are exemplified by piperazineε, εuch aε 2-methylpiper- azine, N-(2-hydroxyethyl)piperazine, 1,2-biε-(N-pipera- zinyl)ethane, and N,N'biε(N-piperazinyl)piperazine,

2-methylimidazoline," 3-aminopiperidine, 2-aminopyridine, 2-(3-aminoethyl)3-pyrroline, 3-aminopyrrolidine, N-(3-aminopropyl)morpholine, etc. Among the heterocyclic compoundε, the piperazineε are preferred.

Another claεε of εuitable polyamineε are diaminoetherε repreεented by Formula IV

H ₂ N-X ₁ f0X ₂ } _r H ₂ IV

wherein X- and X- are independently alkylene from 2 to about 5 carbon atomε and r is an integer from 1 to about 10. Diamines of Formula IV are discloεed in U.S. Patent No. 4,521,610, which is incorporated herein by reference for itε teaching of εuch diamineε.

Typical polyamineε that can be uεed to form the compoundε of this invention by reaction with a poly(oxyalkylene)- chloroformate include the following: ethylene diamine, 1,2-propylene diamine, 1,3-propylene diamine, diethylene triamine, triethylene tetramine, hexamethylene diamine, tetraethylene pentamine, dimethylaminopropylene diamine, N-(beta-aminoethyl)piperazine, N-(beta-aminoethyl)piper- idine, 3-amino-N-ethylpiperidine, N-(beta-aminoethyl)- morpholine, N,N ^r -di(beta-aminoethyl)piperazine, N,N'-di(beta-aminoethylimidazolidone-2; N-(beta-cyano- ethyl)ethane-l,2-diamine, l-amino-3,6,9-triazaoctadecane, l-amino-3,6-diaza-9-oxadecane, N-(beta-aminoethyl)-di- ethanolamine , N' -acetyl-N' -methyl-N- f beta-aminoethyl ) - ethane-l , 2-diamine , N-acetonyl-l , 2-propanediamine , N-( beta-nitroethyl ) -l , 3-propane diamine , l , 3-dimethyl-5- (beta-aminoethyl)hexahydrotriazine, N-(beta-amino- ethyl)hexahydrotriazine, 5-(beta-aminoethyl)-l,3,5-

dioxazine, 2-(2-aminoethylamino)-ethanol, 2[2-(2-amino- ethylamino)ethyl mino]-ethanol.

The amine component of the alkylphenyl poly(oxyalkylene) aminocarbamate may also be derived from an amine-contain- ing compound which is capable of reacting with an alkyl- phenyl poly(oxyalkylene) alcohol to produce an alkylphenyl poly(oxyalkylene) aminocarbamate having at least one basic nitrogen atom. For example, a εubstituted aminoiso- cyanate, εuch aε (RgJ-NCH-CH-NCO, wherein _g is, for example, a hydrocarbyl group, reacts with the alcohol to produce the aminocarbamate additive finding use within the scope of the present invention. Typical aminoisocyanateε that may be used to form the fuel additive compounds of this invention by reaction with a hydrocarbylpoly(oxy- alkylene) alcohol include the following: N,N-(dimethyl)- aminoisocyanatoethane, generally, N,N-(dihydrocarbyl)- aminoiεocyanatoalkane, more generally, N-(perhydrocarbyl)- isocyanatopolyalkylene polyamine, N,N-(dimethyl)aminoiso- cyanatobenzene, etc.

In many inεtanceε the amine uεed aε a reactant in the production of the carbamate of the present invention iε not a εingle compound but a mixture in which one or εeveral compoundε, predominate with the average compoεi- tion indicated. For example, tetraethylene pentamine prepared by the polymerization of aziridine or the reaction of dichloroethylene and ammonia will have both lower and higher amine members, e.g., triethylene tetramine, εubεtituted piperazines and pentaethylene hexamine, but the composition will be mainly tetraethylene pentamine and the empirical formula of the total amine composition will closely approximate that of tetraethylene pentamine. Finally, in preparing the compounds of thiε

01 invention, where the various nitrogen atoms of the poly-

02 amine are not geometrically equivalent, several substitu-

03 tional isomers are possible and are encompassed within the

04 final product. Methods of preparation of amines, iso-

05 cyanates and their reactionε are detailed in Sidgewick'ε

06 "The Organic Chemiεtry of Nitrogen", Clarendon Preεε,

07 Oxford, 1966; Nollers' "Chemistry of Organic Compounds",

08 Saunders, Philadelphia, 2nd Ed. 1957; and Kirk-Othmer's

09 "Encyclopedia of Chemical Technology", 2nd Ed., especially

10 Volume 2, pp. 99-116. 11

12 Preferred Alkylphenyl

13 Poly(oxyalkylene) Aminocarbamate 14

15 Having described the preferred alkylphenyl poly(oxy-

16 alkylene) component and the preferred polyamine component,

17 the preferred alkylphenyl poly(oxyalkylene) aminocarbamate

18 additive of the present invention is obtained by linking

19 theεe componentε together through a carbamate linkage

20 i.e., 21

22

23 0

2 *4* -0-C"-N<

25

26 wherein the ether oxygen may be regarded aε the terminal

27 hydroxyl oxygen of the alkylphenyl pol (oxyalkylene)

28 alcohol component, and the carbonyl group -C(O)- iε

29 preferably provided by the coupling agent, e.g., phoεgene. 30

31 The alkylphenyl poly(oxyalkylene) aminocarbamate employed

32 in the preεent invention haε at leaεt one baεic nitrogen

33 atom per molecule. A "baεic nitrogen atom" iε one that iε

34 titratable by a εtrong acid, e.g., a primary, εecondary,

or tertiary amino nitrogen, aε diεtinguiεhed from, for example, an amido nitrogen, i.e.,

0 I' -CN< ,

which iε not so titratable. Preferably, the baεic nitrogen iε in a primary or εecondary amino group.

The preferred alkylphenyl poly(oxyalkylene) aminocarbamate haε an average molecular weight of from about 800 to 6,000; preferably an average molecular weight of from 800 to 3,000; and moεt preferably an average molecular weight of from 1,000 to 2,500.

A preferred class of alkylphenyl poly(oxyalkylene) amino- carbamate can be described by the following Formula V

R. 0

: :O0CCHH ₂₂ CCHH--)- _n 0CNH-R ₂ NH- H

m wherein R is an alkyl group containing at least 40 carbon atoms; R, is hydrogen or alkyl of 1 to 3 carbon atomε; R ₂ iε alkylene of from 2 to about 6 carbon atomε; m iε an integer from 1 to 2; n iε an integer εuch that the molecular weight of the compound iε from about 800 to 6,000; and p is an integer from 1 to about 6 and with the proviso that if R, is hydrogen then n is an integer from 1 to 25.

Preparation of the Alkylphenyl Poly(oxyalkylene) Aminocarbamate

The additives employed in thiε invention can be most con- veniently prepared by firεt reacting the appropriate alkylphenyl poly(oxyalkylene) alcohol with phoεgene to produce an alkylphenyl poly(oxyalkylene) chloroformate. The chloroformate iε then reacted with the polyamine to produce the deεired alkylphenyl poly(oxyalkylene) aminocarbamate.

Preparation of aminocarbamateε are diεcloεed in U.S. Patent Noε. 4,160,648; 4,191,537; 4,197,409; 4,236,020; 4,243,798; 4,270,930; 4,274,837; 4,288,612; 4,512,610; and 4,568,358, which are incorporated wherein by reference. In general, the reaction of the poly(oxyalkylene) compound and phoεgene iε uεually carried out on an eεεentially equimolar basis, although excesε phosgene can be used to improve the degree of reaction. The reaction may be carried out a temperatures from -10° to 100°C, preferably in the range of 0° to 50°C. The reaction will usually be complete within 1/4 to 5 hours. Times of reaction will uεually be in the range of from 2 to 4 hours.

A solvent may be uεed in the chloroformylation reaction. Suitable solvents include benzene, toluene, etc.

The reaction of the resultant chloroformate with the amine may be carried out neat or preferably in solution. Temper- atureε of from -10° to 200°C. may be utilized, the deεired product may be obtained by water and εtripping uεually be the aid of vacuum, of any reεidual solvent.

The mol ratio of polyamine to polyether chloroformate will generally be in the range from about 2 to 20 mols of

polyamine per mol of chloroformate, and more usually 5 to 15 mols of polyamine per mole of chloroformate. Since suppres- sion of polyεubstitution of the polyamino is usually desired, large molar excesses of the polyamine will be used. Additionally, the preferred adduct is the monocarbamate compound, aε opposed to the bis(carbamate) or diεubεtituted aminoether.

The reaction or reactionε may be conducted with or without the preεence of a reaction solvent. A reaction solvent iε generally employed whenever necessary to reduce the viε- coεity of the reaction product. Theεe εolventε should be stable and inert to the reactants and reaction product. Depending on the temperature of the reaction, the particular chloroformate uεed, the mol ratioε, as well as the reactant concentrations, the reaction time may vary from leεε than 1 minute to 3 hourε.

After the reaction haε been carried out for a εufficient length of time, the reaction mixture may be subjected to extraction with a hydrocarbonwater or hydrocarbonalcohol- water medium to free the product from any lowmolecularweight amine saltε which have formed and any unreacted diamine. The product may then be iεolated by evaporation of the εolvent. Further purification may be effected by column chromatography on εilica gel.

Depending on the particular application of the composition of this invention, the reaction may be carried out in the medium in which it will ultimately find uεe, e.g., polyether carrierε or an oleophilic organic εolvent or mixtureε thereof and be formed at concentrationε which provide a concentrate of a detergent compoεition. Thuε, the final

mixture may be in a form to be used directly for blending in fuels.

An alternative procesε for preparing the alkylphenyl poly- (oxyalkylene) aminocarbamateε employed in thiε invention involves the use of an arylcarbonate intermediate. That iε to say, the alkylphenyl poly(oxyalkylene) alcohol is reacted with an aryl chloroformate to form an arylcarbonate which is then reacted with the polyamine to form the aminocarbamate employed in thiε invention. Particularly uεeful aryl chloroformates include phenyl chloroformate, p-nitrophenyl chloroformate, 2,4-dinitrophenyl chloroformate, p-chloro- phenyl chloroformate, 2,4-dichlorophenyl chloroformate, and p-trifluoromethylphenyl chloroformate. Use of the aryl carbonate intermediate allowε for converεion to amino- carbamateε containing cloεe to the theoretical baεic nitrogen while employing leεε excess of polyamine, i.e., molar ratios of generally from 1:1 to about 5:1 of polyamine to the arylcarbonate, and additionally avoids the generation of hydrogen chloride in the reaction forming the aminocarba- mate. Preparation of hydrocarbyl capped poly(oxyalkylene) aminocarbamates via an arylcarbonate intermediate are dis- cloεed in U.S. Serial Noε. 586,533 and 689,616, which are incorporated herein by reference.

Alεo included within the εcope of this invention are fully formulated lubricating oils containing a dispersant effec- tive amount of an alkylphenyl poly(oxyalkylene) a inocar- bamate. Contained in the fully formulated composition is:

1. an alkenyl εuccinimide,

2. a Group II metal εalt of a dihydrocarbyl dithiophosphoric acid,

3. a neutral or overbased alkali or alkaline earth metal hydrocarbyl sulfonate or ixtureε thereof, and

4. a neutral or overbaεed alkali or alkaline earth metal alkylated phenate or mixtureε thereof.

5. A viεcoεity index (VI) improver.

The alkenyl succinimide is present to act as a disperεant and prevent formation of depoεitε formed during operation of the engine. The alkenyl εuccinimideε are wellknown in the art. The alkenyl succinimides are the reaction product of a polyolefin polymersubstituted succinic anhydride with an amine, preferably a polyalkylene polyamine. The polyolefin polymersubεtituted εuccinic anhydrideε are obtained by reaction of a polyolefin polymer or a derivative thereof with maleic anhydride. The εuccinic anhydride thus obtained is reacted with the amine compound. The preparation of the alkenyl succinimideε haε been deεcribed many times in the art. See, for example, U.S. Patents Nos. 3,390,082; 3,219,666; and 3,172,892, the diεcloεure of which are incor- porated herein by reference. Reduction of the alkenyl εubεtituted εuccinic anhydride yields the corresponding alkyl derivative. The alkyl succinimides are intended to be included within the scope of the term "alkenyl succinimide". A product comprising predominantly mono or bisεuccinimide can be prepared by controlling the molar ratios of the reactants. Thus, for example, if one mole of amine is reacted with one mole of the alkenyl or alkyl subεtituted εuccinic anhydride, a predominantly monoεuccinimide product will be prepared. If two moleε of the εuccinic anhydride are reacted per mole of polyamine, a biεsuccinimide will be prepared.

Particularly good results are obtained with the lubricating oil compositions of thiε invention when the alkenyl succi- nimide iε a polyiεobuteneεubεtituted εuccinic anhydride of a polyalkylene polyamine.

The polyisobutene from which the polyisobuteneεubεtituted εuccinic anhydride is obtained by polymerizing isobutene can vary widely in its compositions. The average number of carbon atomε can range from 30 or leεε to 250 or more, with a reεulting number average molecular weight of about 400 or leεε to 3,000 or more. Preferably, the average number of carbon atomε per polyiεobutene molecule will range from about 50 to about 100 with the polyiεobutenes having a num- ber average molecular weight of about 600 to about 1,500. More preferably, the average number of carbon atoms per polyisobutene molecule ranges from about 60 to about 90, and the number average molecular weight ranges from about 800 to 1,300. The polyisobutene is reacted with maleic anhydride according to wellknown procedureε to yield the polyiso- butene-subεtituted εuccinic anhydride.

In preparing the alkenyl εuccinimide, the substituted succinic anhydride is reacted with a polyalkylene polyamine to yield the corresponding succinimide. Each alkylene radical of the polyalkylene polyamine usually has from 2 up to about 8 carbon atomε. The number of alkylene radicalε can range up to about 8. The alkylene radical iε exem- plified by ethylene, propylene, butylene, trimethylene, tetramethylene, pentamethylene, hexa ethylene, octa- methylene, etc. The number of amino groups generally, but not necessarily, is one greater than the number of alkylene radicals present in the amine, i.e., if a polyalkylene polyamine contains 3 alkylene radicalε, it will usually contain 4 amino radicals. The number of amino radicalε can

01 range up to about 9. Preferably, the alkylene radical

02 containε from about 2 to about 4 carbon atomε and all amine

03 groupε are primary or εecondary. In thiε caεe, the number

04 of amine groupε exceedε the number of alkylene groupε by 1.

05 preferably the polyalkylene polyamine containε from 3 to 5

06 amine groupε. Specific examples of the polyalkylene poly-

07 amineε include ethylenediamine, diethylenetriamine, tri-

08 ethylenetetramine, propylenediamine, tripropylenetetramine,

09 tetraethylenepentamine, trimethylenediamine, pentaethylene-

10 hexamine, di(trimethylene)triamine, tri(hexamethylene)tetra-

11 mine, etc. 12

13 Other amineε εuitable for preparing the alkenyl εuccinimide

14 useful in this invention include the cyclic amines εuch aε

15 piperazine, morpholine and dipiperazineε. 16

17 Preferably the alkenyl εuccinimides used in the compoεitionε

18 of this invention have the following formula 19

20

25 wherein: 26 7 R- represents an alkenyl group, preferably a substan¬ 8 tially saturated hydrocarbon prepared by polymerizing 9 aliphatic mono-olefins. Preferably R. is prepared from 0 isobutene and haε an average number of carbon atoms and 1 a number average molecular weight as described above; 2 3 the "alkylene" radical represents a substantially 4 hydrocarbyl group containing from 2 up to about 8

carbon atoms and preferably containing from about 24 carbon atoms aε deεcribed hereinabove;

c. A repreεentε a hydrocarbyl group, an amine-εubstituted hydrocarbyl group, or hydrogen. The hydrocarbyl group and the amine-subεtituted hydrocarbyl groupε are gener- ally the alkyl and amino-εubεtituted alkyl analogε of the alkylene radicalε deεcribed above. Preferably A repreεentε hydrogen;

d. n repreεentε an integer of from 1 to about 8, and preferably from about 3-5.

Alεo included within the term alkenyl εuccinimide are the modified εuccinimides which are discloεed in U.S. Patent No. 4,612,132 which iε incorporated herein by reference.

The alkenyl succinimide iε present in the lubricating oil compositions of the invention in an amount effective to act aε a diεperεant and prevent the depoεit of contaminantε formed in the oil during operation of the engine. The amount of alkenyl succinimide can range from about 1 percent to about 20 percent weight of the total lubricating oil composition. Preferably the amount of alkenyl succinimide present in the lubricating oil composition of the invention rangeε from about 1 to about 10 percent by weight of the total compoεition.

The alkali or alkaline earth metal hydrocarbyl εulfonateε may be either petroleum sulfonate, εynthetically alkylated aromatic εulfonateε, or aliphatic sulfonates εuch aε those derived from polyisobutylene. One of the more important functionε of the εulfonateε iε to act aε a detergent and diεperεant. Theεe εulfonates are wellknown in the art. The

hydrocarbyl group must have a sufficient number of carbon atoms to render the sulfonate molecule oil soluble. Prefer- ably, the hydrocarbyl portion has at leaεt 20 carbon atomε and may be aromatic or aliphatic, but iε usually alkylaroma- tic. Moεt preferred for uεe are calcium, magnesium or barium sulfonateε which are aromatic in character.

Certain εulfonates are typically prepared by sulfonating a petroleum fraction having aromatic groups, usually mono- or dialkylbenzene groupε, and then forming the metal salt of the sulfonic acid material. Other feedstockε uεed for preparing theεe εulfonateε include εynthetically alkylated benzeneε and aliphatic hydrocarbonε prepared by polymerizing a mono- or diolefin, for example, a polyiεobutenyl group prepared by polymerizing isobutene. The metallic saltε are formed directly or by metatheεiε using well-known procedures.

The sulfonates may be neutral or overbased having base num- berε up to about 400 or more. Carbon dioxide and calcium hydroxide or oxide are the most commonly used material to produce the baεic or overbaεed εulfonateε. Mixtureε of neutral and overbaεed εulfonateε may be used. The sulfo- nates are ordinarily used so as to provide from 0.3% to 10% by weight of the total composition. Preferably, the neutral sulfonateε are preεent from 0.4% to 5% by weight of the total compoεition and the overbased sulfonateε are present from 0.3% to 3% by weight of the total composition.

The phenateε for uεe in thiε invention are thoεe conven- tional productε which are the alkali or alkaline earth metal εaltε of alkylated phenolε. One of the functionε of the phenateε iε to act as a detergent and dispersant. Among other things, it prevents the deposition of contaminants

formed during high temperature operation of the engine. The phenolε may be mono- or polyalkylated.

The alkyl portion of the alkyl phenate iε preεent to lend oil εolubility to the phenate. The alkyl portion can be obtained from naturally occurring or εynthetic sources. Naturally occurring sourceε include petroleum hydrocarbonε εuch aε white oil and wax. Being derived from petroleum, the hydrocarbon moiety is a mixture of different hydrocarbyl groups, the specific composition of which depends upon the particular oil stock which waε uεed aε a εtarting material. Suitable εynthetic sources include various commercially available alkenes and alkane derivativeε which, when reacted with the phenol, yield an alkylphenol. Suitable radicalε obtained include butyl, hexyl, octyl, decyl, dodecyl, hexa- decyl, eicoεyl, tricontyl, and the like. Other εuitable εynthetic εourceε of the alkyl radical include olefin poly- merε such aε polypropylene, polybutylene, polyiεobutylene and the like.

The alkyl group can be εtraight-chained or branch-chained, εaturated or unεaturated (if unsaturated, preferably containing not more than 2 and generally not more than 1 site of olefinic unεaturation) . The alkyl radicals will generally contain from 4 to 30 carbon atoms. Generally when the phenol iε monoalkylsubstituted, the alkyl radical should contain at least 8 carbon atoms. The phenate may be sul- furized if desired. It may be either neutral or overbased and if overbased will have a base number of up to 200 to 300 or more. Mixtures of neutral and overbased phenates may be uεed.

The phenateε are ordinarily preεent in the oil to provide from 0.2% to 27% by weight of the total compoεition.

Preferably, the neutral phenateε are preεent from 0.2% to 9% by weight of the total composition and the overbased phenateε are preεent from 0.2 to 13% by weight of the total compoεition. Moεt preferably, the overbased phenates are present from 0.2% to 5% by weight of the total composition. Preferred metals are calcium, magnesium, strontium or barium.

The sulfurized alkaline earth metal alkyl phenateε are pre- ferred. Theεe salts are obtained by a variety of processes such as treating the neutralization product of an alkaline earth metal base and an alkylphenol with sulfur. Conven- iently the sulfur, in elemental form, iε added to the neutralization product and reacted at elevated temperatures to produce the sulfurized alkaline earth metal alkyl phenate.

If more alkaline earth metal base were added during the neutralization reaction than was necessary to neutralize the phenol, a basic sulfurized alkaline earth metal alkyl phenate iε obtained. See, for example, the process of Walker et al, U.S. Patent No. 2,680,096. Additional basicity can be obtained by adding carbon dioxide to the basic sulfurized alkaline earth metal alkyl phenate. The excesε alkaline earth metal baεe can be added εubεequent to the εulfurization step but is conveniently added at the same time as the alkaline earth metal base is added to neutralize the phenol.

Carbon dioxide and calcium hydroxide or oxide are the most commonly used material to produce the basic or "overbased" phenates. A process wherein baεic εulfurized alkaline earth metal alkylphenates are produced by adding carbon dioxide iε shown in Hanneman, U.S. Patent No. 3,178,368.

The Group II metal εaltε of dihydrocarbyl dithiophoεphoric acidε exhibit wear, antioxidant and thermal stability properties. Group II metal saltε of phoεphorodithioic acidε have been deεcribed previouεly. See, for example, U.S. Patent No. 3,390,080, columnε 6 and 7, wherein these com- pounds and their preparation are deεcribed generally. Suit- ably, the Group II metal salts of the dihydrocarbyl dithiophoεphoric acids useful in the lubricating oil compo- sition of thiε invention contain from about 4 to about 12 carbon atomε in each of the hydrocarbyl radicals and may be the same or different and may be aromatic, alkyl or cyclo- alkyl. Preferred hydrocarbyl groups are alkyl groupε con- taining from 4 to 8 carbon atoms and are represented by butyl, isobutyl, sec.butyl, hexyl, isohexyl, octyl, 2-ethylhexyl and the like. The metalε εuitable for forming these saltε include barium, calcium, strontium, zinc and cadmium, of which zinc iε preferred.

Preferably, the Group II metal εalt of a dihydrocarbyl dithiophoεphoric acid haε the following formula:

wherein: e. R ₂ and R ₃ each independently represent hydrocarbyl radicals as deεcribed above, and

f. M. repreεentε a Group II metal cation aε deεcribed above.

The dithiophoεphoric εalt iε preεent in the lubricating oil compoεitionε of thiε invention in an amount effective to

inhibit wear and oxidation of the lubricating oil. The amount rangeε from about 0.1 to about 4 percent by weight of the total composition, preferably the salt is preεent in an amount ranging from about 0.2 to about 2.5 percent by weight of the total lubricating oil compoεition. The final lubri- eating oil compoεition will ordinarily contain 0.025 to 0.25% by weight phoεphorus and preferably 0.05 to 0.15% by weight.

Viscosity index (VI) improvers are either non-diεperεant or diεperεant VI improverε. Nondisperεant VI improvers are typically hydrocarbyl polymers including copolymers and terpolymers. Typically hydrocarbyl copolymers are copolymers of ethylene and propylene. Such nondispersant VI improverε are diεcloεed in U.S. Patentε Noε. 2,700,633; 2,726,231; 2,792,288; 2,933,480; 3,000,866; 3,063,973; and 3,093,621 which are incorporated herein by reference for their teaching of nondispersant VI improvers.

Disperεant VI improverε can be prepared by functiόnalizing nondisperεant VI improverε. For example, nondiεperεant hydrocarbyl copolymer and terpolymer VI improverε can be functionalized to produce .aminated oxidized VI improverε having dispersant properties and a number average molecular weight of from 1,500 to 20,000. Such functionalized dispersant VI improvers are diεcloεed in U.S. Patentε Nos. 3,864,268; 3,769,216; 3,326,804 and 3,316,177 which are incorporated herein by reference for their teaching of such disperεant VI improverε.

Other diεperεant VI improverε include amine-grafted acrylic polymerε and copolymerε wherein one monomer contains at least one amino group. Typical compositions are described in British Patent No. 1,488,382; and U.S. Patents

Nos. 4,089,794 and 4,025,452, which are incorporated herein by reference for their teaching of such dispersant VI improvers.

Nondisperεant and diεperεant VI improverε are generally employed at from 5 to 20 percent by weight in the lubricating oil compoεition.

Lubricating Oil Compoεitionε

The alkylphenyl poly(oxyalkylene) aminocarbamateε of thiε invention are uεeful aε diεperεant additiveε when employed in lubricating oilε. When employed in thiε manner, the additive iε uεually preεent in from 0.2 to 10 percent by weight to the total compoεition, preferably at about 0.5 to 8 percent by weight and more preferably at about 1 to 6 percent by weight. The lubricating oil uεed with the additive compoεitionε of thiε invention may be mineral oil or εynthetic oils of lubricating viscosity and preferably suitable for uεe in the crankcaεe of an internal combuεtion engine. Crankcaεe lubricating oilε ordinarily have a viεcosity of about 1300 CSt 0°F to 22.7 CSt at 210°F (99°C). The lubricating oils may be derived from εynthetic or natural εourceε. Mineral oil for uεe aε the baεe oil in thiε invention includeε paraffinic, naphthenic and other oils that are ordinarily used in lubricating oil composi- tionε. Synthetic oilε include both hydrocarbon εynthetic oilε and εynthetic eεterε. Uεeful synthetic hydrocarbon oilε include liquid polymers of alpha olefins having the proper viscoεity. Eεpecially uεeful are the hydrogenated liquid oligomerε of C _g to C, ₂ alpha olefinε εuch aε 1-decene trimer. Likewiεe, alkyl benzeneε of proper viεcoεity εuch aε didodecyl benzene, can be uεed. Uεeful εynthetic eεterε include the eεterε of both monocarboxylic acid and

polycarboxylic acidε aε well aε onohydroxy alkanolε and polyolε. Typical exampleε are didodecyl adipate, pentaerythritol tetracaproate, di-2-ethylhexyl adipate, dilaurylεebacate and the like. Complex esters prepared from mixtures of mono and dicarboxylic acid and mono and dihydroxy alkanols can alεo be uεed.

Blendε of hydrocarbon oilε with εynthetic oilε are alεo uεeful. For example, blendε of 10 to 25 weight percent hydrogenated 1-decene trimer with 75 to 90 weight percent 150 SUS (100°F) mineral oil giveε an excellent lubricating oil baεe.

Additive concentrateε are alεo included within the εcope of this invention. The concentrates of thiε invention uεually include from about 90 to 50 weight percent of an oil of lubricating viεcoεity and from about 10 to 50 weight percent of the additive of thiε invention. Typically, the concen- trates contain sufficient diluent to make them easy to handle during εhipping and storage. Suitable diluents for the concentrates include any inert diluent, preferably an oil of lubricating viscosity, so that the concentrate may be readily mixed with lubricating oils to prepare lubricating oil compositionε. Suitable lubricating oils which can be used aε diluentε typically have viεcoεitieε in the range from about 35 to about 500 Saybolt Univerεal Seconds (SUS) at 100°F (38°C), although an oil of lubricating viscosity may be used.

Other additives which may be present in the formulation include rust inhibitors, foam inhibitors, corroεion inhibitors, metal deactivators, pour point depressantε, antioxidantε, and a variety of other well-known additives.

Fuel Compoεitionε

The alkylphenyl poly(oxyalkylene) aminocarbamates of this invention will generally be employed in a hydrocarbon diεtillate fuel. The proper concentration of thiε additive necessary in order to achieve the desired detergency and disperεancy varieε depending upon the type of fuel employed, the preεence of other detergents, dispersantε and other additives, etc. Generally, however, from 30 to 5,000 weight parts per million (ppm), and preferably 100 to 500 ppm and more preferably 200 to 300 ppm of alkylphenyl poly(oxy- alkylene) aminocarbamate per part of base fuel iε needed to achieve the beεt results. When other detergents are present, a less amount of alkylphenyl pol (oxypropylene) aminocarbamate may be used. For performance as a carburetor detergent only, lower concentrations, for example 30 to 100 ppm may be preferred. Higher concentrations, i.e., 2,000 to 5,000 ppm may result in a clean-up effect on combuεtion chamber depoεitε aε well aε the entire intake εyεtem.

The depoεit control additive may alεo be formulated as a concentrate, using an inert stable oleophilic organic solvent boiling in the range of about 150 to 400°F. Prefer- ably, an aliphatic or an aromatic hydrocarbon solvent is used, εuch aε benzene, toluene, xylene or higherboiling aromaticε or aromatic thinnerε. Aliphatic alcoholε of about 3 to 8 carbon atoms, such aε isopropanol, isobutylcarbinol, n-butanol and the like, in combination with hydrocarbon εolvents are alεo εuitable for uεe with the detergent-diε- perεant additive. In the concentrate, the amount of the additive will be ordinarily at leaεt 5 percent by weight and generally not exceed 50 percent by weight, preferably from 10 to 30 weight percent.

When employing certain of the alkylphenyl poly(oxyalkylene) aminocarbamates of this invention, particularly those having more than 1 basic nitrogen, it can be desirable to addi- tionally add a demulsifier to the gaεoline or diesel fuel composition. These demulsifierε are generally added at from 1 to 15 ppm in the fuel compoεition. Suitable demulsifiers include for instance L-1562?, a high molecular weight glycol capped phenol available from Petrolite Corp., Tretolite Division, St. from Chevron Chemical Company, San Franciεco, California.

In gaεoline fuelε, other fuel additives may also be included εuch aε anti-knock agents, e.g., methylcyclopentadienyl manganeεe tricarbonyl, tetramethyl or tetraethyl lead, tertbutyl methyl peroxide or other dispersants or detergents such as various subεtituted εuccinimideε, amineε, etc. Alεo included may be lead εcavengerε εuch aε aryl halideε, e.g., dichlorobenzene or alkyl halideε, e.g., ethylene dibromide. Additionally, antioxidantε, metal deactivatorε and demulεifierε may be preεent.

In dieεel fuelε, other well-known additiveε can be employed such aε pour point depresεantε, flow improverε, cetane improverε, etc.

The following exampleε are offered to specifically illus- trate this invention. These exampleε and illuεtrations are not to be construed in any way aε limiting the εcope of thiε invention.

EXAMPLES Example 1

Preparation of C _gς to C _7Q Alkylphenyl Poly(oxypropylene) Alcohol

To a dried 5-liter, 3-neck flaεk under a nitrogen atmo- εphere waε added 1.5 literε of dry toluene and 1125 gramε H-100 (an alkylphenol, prepared from polybutene-24, having a hydroxyl number of approximately 34, and a number average of approximately 65-70 carbon atomε in the alkyl portion of the alkylphenol. H-100? alεo containε approxi- mately onethird (1/3) inactive compoundε. H-100 is available from Amoco Petroleum Additives Company, Clayton, Misεouri). The εyεtem was warmed to approximately 60°C and 5.5 gramε (0.14 moles) of metallic potasεium cut into small pieces waε slowly added with vigorouε εtirring. The temperature of the reaction εyεtem waε allowed to increaεe during thiε addition and reached approximately 105°C. After 2-1/2 hourε, all of the metallic potaεεiu waε diεεolved. The reaction εystem was then allowed to cool to 40°C. Afterwards, 131.5 gramε (about 5 equivalentε per equivalent of alkylphenol) of propylene oxide waε added to the εyεtem by an addition funnel at an addition rate εlow enough to avoid flooding of the vapor condenεing εyεtem. The εyεtem waε then gently refluxed for 13 hourε at which point the temperature increaεed to 113°C and waε held there for an addition 3.5 hourε. The εyεtem waε then cooled to 60°C and the reaction quenched by the addition of 0.075 liter of 2N HCl εolution. The εystem waε then dried by azeotropic distillation to yield a toluene solution of the crude product. The syεtem waε then diluted with 1 liter of toluene.

Example 2

Preparation of C _g5 to C _7Q Alkylphenyl Poly(oxypropylene) Chloroformate

The toluene εolution containing the product of Example 1 above in a 5-liter, 3-neck flaεk under a nitrogen atmo- εphere waε cooled to about 5°C with stirring. While stirring, 301 grams of a 20% solution of phosgene in toluene was added all at once to the reaction system. The reaction system was allowed to warm to room temperature and stirred gently for 24 hourε. In order to remove excess phosgene aε well as HCl formed during the reaction, the εyεtem waε vigorouεly εparged with nitrogen. After completion of the reaction, an infrared analysis of an aliquot revealed a strong chloroformate absorption at 1785 cm -1 and no detectable alcohol absorption at 3450 cm-1

Example 3

Preparation of C _gς to C_ ₀ Alkylphenyl Poly(oxypropylene) Ethylene Diamine Carbamate

The entire chloroformate/toluene solution of Example 2 waε diluted with 4 literε of dry toluene. In a εeparate flask, 487 grams of ethylene diamine (8.1 moles) approxi- mately 20 equivalents per equivalent of chloroformate, waε also diluted with 4 liters of dry toluene. At room tem- perature, these two εolutionε were rapidly mixed uεing two variable εpeed Teflon gear pumpε and a 10-inch Kenicε εtatic mixer. After fifteen minuteε, the crude reaction mixture waε εtripped, diluted with 10 liters of hexane, and washed εucceεεively once with water and three timeε with a εlightly baεic (pH =9) brine εolution. Phase

εeparation of the aqueouε brine εolution and the hexane εolution was improved by adding isopropanol aε needed. The hexane εolution waε εeparated, dried over anhydrous sodium εulfate, filtered and εtripped to afford the title product as a thick orange liquid having an alkalinity value of 17.7 and 0.44 weight percent basiε nitrogen.

Example 4

Preparation of C _gς to C _7Q Alkylphenol Poly(oxypropylene) Diethylene Triamine Carbamate

In the manner deεcribed in Example 3 above, a _ _gr - to C ₇₀ alkylphenyl poly(oxypropylene) chloroformate (prepared from 1168 gramε of H-100? alkylphenol, 0.73 moleε) pre- pared εimilarly to the methodε described in Examples 1 and 2 above was treated with 814 grams (7.89 moles), approxi- mately 20 equivalents per equivalent of chloroformate, of diethylene triamine to afford the title compound having an alkalinity value of 25.7 and 0.64 weight percent basic nitrogen.

Reference Example A

Preparation of Tetrapropenylphenol

To a 2-liter flask, equipped with stirrer, Dean Stark trap, condenεor, and nitrogen inlet and outlet waε added 567 gramε of tetrapropylene, 540 gramε of phenol, 72 gramε of a εulfonic acid cation exchange reεin (polyεtyrene croεεlinked with divinylbenzene) catalyεt (Amberlyεt 15 available from Rohm and Haas, Philadelphia, Pennsylvania). The reaction mixture waε heated to about 110°C for about 3 hours with stirring under a nitrogen atmosphere. The

reaction mixture was stripped by heating under vacuum and the resulting product filtered hot over diatomaceous earth to afford 626 grams of tetrapropenylphenol and with a hydroxyl number of 205 and with 96% paraalkylphenol content.

Reference alkylphenyl poly(oxyalkylene) aminocarbamateε were prepared from the tetrapropenyl alkylphenol of Reference Example A in a manner εimilar to Exampleε 1-4 above. Reference Examples B through D found in Table I below summarizes the different tetrapropenylphenyl poly(oxyalkylene) aminocarbamates so prepared.

TABLE I

COMPOUNDS OF THE FORMULA

R., _^ 0

R ₃ -0CH ₂ CH-)- 0CNH-R ₂ H^ H

Example R,

B tetrapropenylphenyl

C tetrapropenylphenyl

D tetrapropenylphenyl

3 C _g5 to C ₇₀ alkylphenyl

4 Cg _c to C ₇₀ alkylphenyl

Example 5

Oil Solubility Bench Test

This procedure waε deεigned to determine the oil solubil¬ ity/compatibility of different additives in a fully formulated lubricating oil. Insofar aε up to 25-30% of a

gasoline additive can enter into the crankcase via "blow-by" and/or cylinder wall/piston ring "wipe down", this is an important performance criteria.

The lubricating oil composition was formulated to contain: 6 percent by weight of a mono-polyiεobutenyl succinimide; 20 millimoles per kilogram of a highly overbased sul- furized calcium phenate; 30 millimoles per kilogram of a highly overbased sulfurized calcium hydrocarbyl sulfonate; 22.5 millimoleε per kilogram of a zinc dithiophosphate; 13 weight percent of a commercial nondisperεant C ₂ ~C ₃ copolymer viεcoεity index improver; 5 partε per million of a foam inhibitor in 150N Exxon baεe oil to give a 10 W 40 formulated oil.

The oil εolubility of the additive waε determined aε followε:

To a heated εolution (50 gramε) of the above-deεcribed fully formulated lubricating oil waε added 50 gramε of the neat additive. The mixture waε then heated with conεtant εtirring to 170°F and maintained at that temperature for 15 minuteε. Dilutions were then prepared according to the desired solubility test range uεing freεh hot reference oil aε the diluent. In each caεe, the diluted εampleε were stirred to 170°F for 10 minutes to insure complete mixing. The solutionε were then εealed and left to cool undiεturbed for from 1-5 dayε typically at room tempera- ture. Each εample waε then rated viεually for oil continuity.

Additiveε that were marginally εoluble in this blend separated as a denεer secondary phase, and were clearly visible aε such without the need for centrifugation.

Additiveε which gave riεe to oil incompatibility problemε were inherently oil εoluble, however, they tended to diεplace what appearε to be the VI improver. Thiε phenomenon reεulted in the εeparation of the VI improver which is lesε dense than the bulk oil forming a clear thick upper layer. The solubility/compatibility of a gaεoline additive waε thereby defined as the highest con¬ centration (on a weight baεis) which did not result in the formation of either an insoluble lower additive phase or an insoluble upper VI improver phase.

Table II below contains compatibility data for the hydrocarbyl poly(oxyalkylene) aminocarbamate. Oil compatibility is reported aε weight percent of additive in the lubricating oil compoεition.

TABLE II

Example Oil Compatibility (Wt %)

3 50

4 50 B 15 C 7 D 11

The above data demonεtrates that the additiveε of the instant invention posεeεε improved oil compatibility over prior art compoundε.