EP0473746A1 - Two-cycle engine fuel composition - Google Patents

Abstract

Lubricating oils that are used in two-stroke engines sometimes cause blockage (gelation) in the fuel filters. Gelation is particularly supported when a composition containing an alkali metal or an alkaline earth metal is present in the lubricating oil or the fuel. The present invention solves this particular problem by introducing a hydrocarbon soluble or a dispersible polycarboxylic acid into the mixture of fuel and oil.

Description

Two-cycle Engine Fuel Composition

INTRODUCTION TO THE INVENTION

Field of the invention.

This invention relates to compositions which are useful in avoiding gelation of organic components in a two-cycle engine.

Description of the art.

Two-cycle engines are engines which do not maintain a crankcase for lubrication of the moving parts within the engine. Rather, in a two-cycle engine (two-stroke) the oil of lubricating viscosity required for the moving parts is mixed with the fuel.

Typically, the oil of lubricating viscosity may be either mixed with the fuel manually prior to addition, or mixed within the fuel handling system. The mixing of the oil of lubricating viscosity and the fuel may be accomplished by stirring the ingredients together or in more sophisticated equipment by maintaining a reservoir for the oil with a suitable means to inject the requisite quantities of oil into the fuel shortly before usage. The oil injection system is particularly useful in situations where the oil of lubricat¬ ing viscosity and the gasoline are not compatible. By incompatibility it is meant that the oil of lubricating viscosity and/or the gasoline component react in some fashion to form a gel. If the gelation occurs in a fuel filter or fuel line the engine will stop running with foreseeable undesired consequences.

Some components in certain two-cycle oils tend to react with alkali metal or alkaline earth metal containing compositions. The alkali or alkaline earth metal containing compositions are utilized as valve seat protection lead replacements in fuels. In this regard see United States Patent 4,659,338 issued April 21, 1987 to Johnston and Dorer. Typically, two-cycle engines do not require valve seat reces¬ sion protection, however, the increased usage of alkali or alkaline earth metal containing compositions in gasoline means that it is possible that a lead replacement fuel will be supplied to a two-cycle engine. Should the two-cycle engine contain an oil .of lubricating viscosity which is reactive with the alkali or alkaline earth metal containing composition gelation may result. Therefore the present invention is directed to lubricating oil compositions, two-cycle fuels, and a method for preventing such gelation.

United States Patent 3,169,980 issued February 16, 1965 to Benoit states that fatty acid polyamide compositions may be utilized in internal combustion engine for lubricants and fuels. It is known that oils containing sulfurized alkyl- phenols may be utilized in two-cycle engine oils from the disclosures in United States Patent 4,740,321 issued April 26, 1988 to Davis et al. Aminophenols for use in two-cycle engine oils are discussed in Canadian Patent 1,096,886 to Lange issued March 3, 1981.

It is known from Dorer (Canadian Patent 910,759 issued September 26, 1982) that alkali metal salts of succinic acid may be introduced to gasoline. It is also known from Euro¬ pean published Patent Application 0 207 560 by van Es dated January 7, 1987 that succinic acid salts may be employed in gasoline. It is also known from United States Patent 3,787,374 issued January 22, 1974 to Adams that carboxylic compositions may be utilized as detergents in lubricating oils, fuels such as gasoline or diesel oils, and in hydraulic fluids.

The preparation of metal salts of hydrocarbon-sub¬ stituted succinic acids are described in Le Seur, United States Patent 3,271,310 issued September 6, 1966. The compositions of Le Seur are stated to be useful as deter¬ gents and rust inhibitors in lubricating oils. United States 4,502,970 issued March 5, 1986 to Schetelich et al describes the use of polyisobutenyl succinic anhydride as a supplemen- tal-dispersant detergent in combination with a conventional lubricating oil dispersant.

It is known from Orelup United States Patent 1,692,784 issued November 20, 1928 that low molecular weight organic acids such as myristic, linolic, ricinoleic, stearic, hydroxy stearic, lauric, oleic, iso-oleic, palmitic, capronic, caprylic, caprinic, arachiedic, elaidic, erucic, elaeo- stearic, margaric, and elaeo-margaric acids may be included in a fuel composition. Orelup uses the low molecular weight acids to clean carbon from engine walls. It is also known from Cantrell et al in United States Patent 2,862,800 issued December 2, 1958 that fatty acids having a long, uninter¬ rupted carbon chain derived from naturally occurring fats and oils are desirable ingredients for use in gasoline fuel compositions. The purpose to which the fatty acids of Cantrell are put is for the prevention of engine stalling in a spark ignition type internal combustion engine.

Throughout the specification percentages and ratios are given by weight unless otherwise indicated. Temperatures given herein are in degrees Celsius and pressures are in KPa gauge unless otherwise indicated. Ranges recited herein may be combined. To the extent that any of the references cited herein are applicable to the invention they are specifically incorporated by reference.

SUMMARY OF THE INVENTION This invention describes a composition for internal combustion engines comprising a major amount of a liquid hydrocarbon fuel and a minor amount of:

(A) at least one hydrocarbon-soluble alkali or alkaline earth metal containing composition containing at least 8 aliphatic carbon atoms and

(B) at least one hydrocarbon-soluble ashless dispersant, and

(C) a hydrocarbon-soluble polycarboxylic acid.

A further embodiment of the present invention is a composition suitable for use in an internal combustion engine comprising a major amount of a liquid hydrocarbon fuel and a minor amount sufficient to reduce valve seat recession when the fuel is used in an internal combustion engine of:

(A) at least one neutral hydrocarbon soluble alkali metal sulfonate wherein the sulfonate is the alkali metal η salt of a sulfonic acid of the formula R (SO H) or

2 l 2 .

(R )xT(SOJ_H)y in w-hich R and R are each independently aliphatic groups, R contains at least about 15 carbon atoms, the sum of the number of carbon atoms m (R 2) and T is at least about 15, T is an aromatic hydrocarbon nucleus, and x is a number of 1 to 3, r and y are numbers of 1 to 4 and

(B) at least one hydrocarbon-soluble dispersant which is an amino phenol containing compound having a substituent of a least about 30 aliphatic carbon atoms, and

(C) a hydrocarbyl-substituted succinic acid wherein the hydrocarbyl substituent contains from about 30 to 150 carbon atoms.

A composition is also described herein as:

(A) at least one hydrocarbon-soluble alkali or alkaline earth metal containing composition containing at least 8 aliphatic carbon atoms and

(B) at least one hydrocarbon-soluble ashless disper¬ sant, and

(C) a hydrocarbon-soluble polycarboxylic acid.

The present invention also describes a method of reducing gelation of organic material in a two-cycle engine comprising having present with gasoline and an oil of lubricating viscosity, a minor amount of a hydrocarbyl-substituted polycarboxylic acid.

A further feature of the invention is a two cycle oil comprising an oil of lubricating viscosity, a component which is a fatty acid of about 8 to about 22 carbon atoms or a component capable of generating a fatty acid of about 8 to about 22 carbon atoms and a hydrocarbon soluble succinic acid containing a hydrocarbyl derivative on at least one of the carbons alpha to a carboxyl group wherein there are at least 30 carbon atoms in the hydrocarbyl group.

Yet another embodiment of the invention is a method of reducing gelation in an internal combustion gasoline engine comprising including in the gasoline a hydrocarbon-soluble polycarboxylic acid.

A further feature of the invention is a mixture of .a major amount of an oil of lubricating viscosity containing a minor amount of an oil-soluble polycarboxylic acid having a hydrocarbyl group of 30 or more carbon atoms said mixture being substantially free of water.

DETAILED DESCRIPTION OF THE INVENTION

The compositions and the method of intended use of the present invention are for two-cycle engines. As previously stated two-cycle engines seldom require valve seat recession protection, however, current technology allows for the valve seat recession component to be added generally to gasoline which then may be contacted with a two-cycle oil. In any event, when the lead replacement is contacted with a two-cy¬ cle oil gelation may occur.

In particular, the present invention relates to gaso¬ line for two-cycle engines such as are found in marine, garden or lawn implements. The gasoline utilized in the present invention includes those designated by ASTM speci¬ fication D-439-86 and are composed of a mixture of various types of hydrocarbons including aromatics, olefins, paraf¬ fins, isoparaffins, naphthenes and occasionally diolefins. Gasolines normally have a boiling range for the predominant components therein of about 20^βC to about 230^βC. The Alkali or Alkaline Earth Metal Containing Composition

The fuel compositions of the present invention will contain a minor amount of (A) at least one hydrocarbon- soluble alkali or alkaline earth metal-containing composi¬ tion. The presence of such metal-containing compositions in the fuel compositions provides the fuel composition with a desirable ability to prevent or minimize valve seat recession in internal combustion engines, particularly when the fuel is an unleaded or low-lead fuel.

The choice of the metal does not appear to be partic¬ ularly critical although alkali metals are preferred, with sodium being the preferred alkali metal.

The metal-containing composition (A) may be alkali metal or alkaline earth metal salts of sulfur acids, carboxylic acids, phenols and phosphorus acids. These salts can be neutral or basic. The former contain an amount of metal cation just sufficient to neutralize the acidic groups present in salt anion; the latter contain an excess of metal cation and are often termed overbased, hyperbased or superbased salts. Some of the free acid form of the anion may be present with the salt.

These basic and neutral salts can be of oil-soluble organic sulfur acids such as sulfonic, sulfamic, thiosul- fonic, sulfinic, sulfenic, partial ester sulfuric, sulfurous and thiosulfuric acid. Generally they are salts of aliphatic or aromatic sulfonic acids.

The sulfonic acids include the mono- or poly-nuclear aromatic or cycloaliphatic compounds. The sulfonic acids can be represented for the most part by the following formulae:

R¹(S0₃H)_r Formula I

(R²)xT(SOJH)y Formula II in which T is an aromatic nucleus such as, for example, benzene, naphthalene, anthracene, phenanthrene, diphenylene oxide, thianthrene, phenothioxine, diphenylene sulfide, phenothiazine, diphenyl oxide, diphenyl sulfide, diphenyl- amine, cyclohexane, petroleum naphthenes, decahydronaphthal- ene, cyclopentane, etc; R 1 and R2 are each independently aliphatic groups, R contains at least about 15 carbon atoms, the sum of the carbon atoms in (R 2) and T is at least about

15, and r, x and y are each independently 1 or greater.

Speci .fi.c examples of R1 are groups derived from petro¬ latum, saturated and unsaturated paraffin wax, and polyole- fins, including polymerized C,, C_, C., C_g, C_g, etc., olefins containing from about 15 to 7000 or more carbon atoms. The groups T, R 1 and R2 i.n the above formulae can also contain other inorganic or organic substituents in addition to those enumerated above such as, for example, hydroxy, mercapto, halogen, nitro, amino, nitroso, sulfide, disulfide, etc. The subscript x is generally 1-3, and the subscripts r + y generally have an average value of about 1-4 per molecule.

The following are specific examples of oil soluble sulfonic acids coming within the scope of Formulae I and II above, and it is to be understood that such examples serve also to illustrate the salts of such sulfonic acids useful in this invention. In other words, for every sulfonic acid enumerated it is intended that the corresponding neutral and basic metal salts thereof are also understood to be illus¬ trated. Such sulfonic acids are mahogany sulfonic acids; bright stock sulfonic acids; sulfonic acids derived from lubricating oil fractions having a Saybolt viscosity from about 100 seconds at 100°F (37.7"C) to about 200 seconds at 210°F (99^βC) ; petrolatum sulfonic acids; mono- and poly-wax substituted sulfonic and polysulfonic acids of, e.g., benzene, diphenylamine, thiophene, alpha-chloronaphthalene, etc. ; other substituted sulfonic acids such as alkyl benzene sulfonic acids (where the alkyl group has at least 8 car¬ bons) , cetylphenol mono-sulfide sulfonic acids, dicetyl thianthrene disulfonic acids, dilauryl beta naphthyl sulfonic acids, and alkaryl sulfonic acids such as dodecyl benzene "bottoms" sulfonic acids.

The latter are acids derived from benzene which has been alkylated with propylene tetramers or .isobutene trimers to introduce 1, 2, 3 or more branched-chain C_₂ substituents on the benzene ring. Dodecyl benzene bottoms, principally mixtures of mono- and di-dodecyl benzenes, are available as by-products from the manufacturer of household detergents. Similar products obtained from alkylation bottoms formed during manufacture of linear alkyl sulfonates (LAS) are also useful in making the sulfonates used in this invention.

The production of sulfonates from detergent manufacture by-products by reaction with, e.g., SO , is well known to those skilled in the art. See, for example, the article "Sulfonates" in Kirk-Othmer "Encyclopedia of Chemical Tech¬ nology", Second Edition, Vol. 19, pp. 291 et seq. published by John Wiley & Sons, N.Y. (1969) .

Other descriptions of neutral and basic sulfonate salts and techniques for making them can be found in the following U.S. Patents: 2,174,110; 2,174,506; 2,174,508; 2,193,824; 2,197,800; 2,202,781; 2,212,786; 2,213,360; 2,228,598; 2,223,676; 2,239,974; 2,263,312; 2,276,090; 2,276,097; 2,315,514; 2,319,121; 2,321,022; 2,333,568; 2,333,788; 2,335,259; 2,337,552; 2,347,568; 2,366,027; 2,374,193; 2,383,319; 3,312,618; 3,471,403; 3,488,284; 3,595,790 and 3,798,012. These patents are hereby incorporated by refer¬ ence for their disclosures in this regard. Also included are aliphatic sulfonic acids such as paraffin wax sulfonic acids, unsaturated paraffin wax sulfonic acids, hydroxy-substituted paraffin wax sulfonic acids, hexapropylene sulfonic acids, tetra-amylene sulfonic acids, polyisobutene sulfoinc acids wherein the polyisobutene contains from 20 to 7000 or more carbon atoms, chlorosubstituted paraffin wax sulfonic acids, nitroparaffin wax sulfonic acids, etc; cycloaliphatic sulfonic acids such as petroleum naphthene sulfonic acids, cetyl cyclopentyl sulfonic acids, lauryl cyclohexyl sulfonic acids, bis-(di-isobutyl) cyclohexyl sulfonic acids, mono- or poly-wax substituted cyclohexyl sulfonic acids, etc.

With respect to the sulfonic acids or salts thereof described herein and in the appended claims, it is intended herein to employ the term "petroleum sulfonic acids" or "petroleum sulfonates" to cover all sulfonic acids or the salts thereof derived from petroleum products. A particu¬ larly valuable group of petroleum sulfonic acids are the mahogany sulfonic acids (so called because of their reddish- brown color) obtained as a by-product from the manufacturer of petroleum white oils by a sulfuric acid process.

The carboxylic acids from which suitable neutral and basic alkali metal and alkaline earth metal salts for use in this invention can be made include aliphatic, cycloali¬ phatic, and aromatic mono and polybasic carboxylic acids such as the naphthenic acids, alkyl- or alkenyl-substituted cyclopentanoic acids, the corresponding cyclohexanoic acids and the corresponding aromatic acids. The aliphatic acids generally contain at least eight carbon atoms and preferably at least twelve carbon atoms. Usually they have no more than about 400 carbon atoms. Generally, if the aliphatic carbon chain is branched, the acids are more oil soluble for any given carbon atom content. The cycloaliphatic and aliphatic carboxylic acids can be saturated or unsaturated. Specific examples include 2-ethylhexanoic acid, alpha-linolenic acid, propylenetetramer-substituted maleic acid, behenic acid, isostearic acid, pelargonic acid, capric acid, palmitoleic acid, linoleic acid, lauric acid, oleic acid, ricinoleic acid, undecylic acid, dioctylcyclo-pentane carboxylic myris¬ tic acid, dilauryldecahydro-naphthalene carboxylic acid, stearyl-octahydroindene carboxylic acid, palmitic acid, commercially available mixtures of two or more carboxylic acids such as tall oils acids, rosin acids, and the like.

A preferred group of oil-soluble carboxylic acids useful in preparing the salts used in the present invention are the oil-soluble aromatic carboxylic acids. These acids are represented by the general formula:

(R*)_aAr*(CXXH)_m Formula III where R* is an aliphatic hydrocarbon-based group of at least four carbon atoms, and no more than about 400 aliphatic carbon atoms, a is an integer of from one to four, Ar* is a polyvalent aromatic hydrocarbon nucleus of up to about 14 carbon atoms, each X is independently a sulfur or oxygen atom, and m is an integer of from one to four with the proviso that R* and a are such that there is an average of at least 8 aliphatic carbon atoms provided by the R* groups for each acid molecule represented by Formula III. Examples of aromatic nuclei represented by the variable Ar* are the polyvalent aromatic radicals derived from benzene, naphtha¬ lene, anthracene, phenanthrene, indene, fluorene, biphenyl, and the like. Generally, the radical represented by Ar* will be a polyvalent nucleus derived from benzene or naphthalene such as phenylenes and naphthlene, e.g., methylphenylenes, ethoxy-phenylenes, nitrophenylenes, isopropyl-phenylenes, hydroxyphenylenes, mercaptophenylenes, N,N-diethylaminophe- nylenes, chlorophenylenes, dipropoxynaphthylenes, triethyl- naphthylenes, and similar tri-, tetra-, pentavalent nuclei thereof, etc.

The R* groups are usually purely hydrocarbyl groups, preferably groups such as alkyl or alkenyl radicals. How¬ ever, the R* groups can contain small number substituents such as phenyl, cycloalkyl (e.g., cyclohexyl, cyclopentyl, etc.) and nonhydrocarbon groups such as nitro, amino, halo (e.g., chloro, bromo, etc.) lower alkoxy, lower alkyl mer- capto, oxo substituents (i.e. ,=0) , thio groups (i.e. ,=S) , interrupting groups such as -NH-, -0-, -S-, and the like provided the essentially hydrocarbon character of the R* group is retained. The hydrocarbon character is retained for purposes of this invention so long as any non-carbon atoms present in the R* group do not account for more than about 10% of the total weight of the R* groups.

Examples of R* groups include butyl, isobutyl, pentyl, octyl, nonyl, dodecyl, docosyl, tetracontyl, 5-chlorohexyl, 4-ethoxypentyl, 2-hexenyl, cyclohexyloctyl, 4-(p-chloro- phenyl)-octyl, 2,3,5-trimethylheptyl, 2-ethyl-5-methyloctyl, and substituents derived from polymerized olefins such as polychloroprenes, polyethylenes, polypropylenes, polyiso- butylenes, ethylenepropylene copolymers, chlorinated olefin polymers, oxidized ethylenepropylene copolymers, and the like. Likewise, the group Ar may contain non-hydrocarbon substituents, for example, such diverse substituents as lower alkoxy, lower alkyl mercapto, nitro, halo, alkyl or alkenyl groups of less than four carbon atoms, hydroxy, mercapto and the like.

A group of particularly useful carboxylic acids are those of the formula:

R*aAr* (CXXH Xinp Formula IV where R*, X, Ar*, m and a are as defined in Formula III and p is an integer of 1 to 4, usually 1 or 2. Within this group, an especially preferred class of oil-soluble Carboxylic acids are those of the formula:

(R**)_aPh(C00H)_b(0H)_c Formula V where R** in Formula V is an aliphatic hydrocarbon group containing at least 4 to about 400 carbon atoms, Ph is a phenyl group, a is an integer of from 1 to 3, b is 1 or 2, c is zero, 1, or 2 and preferably 1 with the proviso that R** and a are such that the acid molecules contain at least an average of about twelve aliphatic carbon atoms in the aliphatic hydrocarbon substituents per acid molecule. And within this latter group of oil-soluble carboxylic acids, the aliphatic-hydrocarbon substituted salicylic acids wherein each aliphatic hydrocarbon substituent contains an average of at least about sixteen carbon atoms per substituent and one to three substituents per molecule are particularly useful. Salts prepared from such salicylic acids wherein the aliphatic hydrocarbon substituents are derived from polymer¬ ized olefins, particularly polymerized lower 1-mono-olefins such as polyethylene, polypropylene, polyisobutylene, ethylene/propylene co-polymers and the like and having average carbon contents of about 30 to 400 carbon atoms.

The carboxylic acids corresponding to Formulae III and IV above are well known or can be prepared according to procedures known in the art. Carboxylic acids of the type illustrated by the above formulae and processes for preparing their neutral and basic metal salts are well known and disclosed, for example, in such U.S. Patents as 2,197,832; 2,197,835; 2,252,662; 2,252,664; 2,714,092; 3,410,798 and 3,595,791.

Another type of neutral and basic carboxylate salt used in this invention are those derived from alkenyl succinates of the general formula:

R*CH(COOH)CH₂COOH Formula VI wherein R* is as defined above in Formula III. Such salts and means for making them are set forth in U.S. Patents 3,271,130; 3,567,637 and 3,632,610.

Other patents specifically describing techniques for making basic salts of the hereinabove-described sulfonic acids, carboxylic acids, and mixtures of any two or more of these include U.S. Patent Nos. 2,501,731; 2,616,904; 2,616,905; 2,616,906; 2,616,911; 2,616,924; 2,616,925; 2,617,049; 2,777,874; 3,027,325; 3,256,186; 3,282,835; 3,384,585; 3,373,108; 3,368,396; 3,342,733; 3,320,162; 3,312,618; 3,318,809; 3,471,403; 3,488,284; 3,595,790; and 3,629,109.

Neutral and basic salts of phenols (generally known as phenates) are also useful in the compositions of this inven¬ tion and well Jcnown to those skilled in the art. The phenols from which these phenates are formed are of the general formula:

(R*)_a-(Ar*)-(OH)_m Formula VII wherein R*, a, Ar*, and m have the same meaning and preferences as described hereinabove with reference to Formula III. The same examples described with respect to Formula III also apply.

The commonly available class of phenates are those made from phenols of the general formula:

(R^,)_a (R⁴)_z Ph(OH)_b Formula VIII wherein a is an integer of 1-3, b is of 1 or 2, z is 0 or 1, Ph is a phenyl group R' in Formula VIII is a substantially saturated hydrocarbon-based substituent having an average of from about 30 to about 400 aliphatic carbon atoms and R 4 is selected from the group consisting of lower alkyl, lower alkoxyl, nitro, and halo groups.

One particular class of phenates for use in this inven¬ tion are the basic (i.e., overbased, etc.) alkali and alka¬ line earth metal sulfurized phenates made by sulfurizing a phenol and described hereinabove with a sulfurizing agent such as sulfur, a sulfur halide, or sulfide or hydrosulfide salt. Techniques for making these sulfurized phenates are described in U.S. Patents 2,680,096; 3,036,971 and 3,775,321.

Other phenates that are useful are those that are made from phenols that have been linked through alkylene (e.g., methylene) bridges. These are made by reacting single or multi-ring phenols with aldehydes or ketones, typically, in the presence of an acid or basic catalyst. Such linked phenates as well as sulfurized phenates are described in detail in U.S. Patent 3,350,038; particularly columns 6-8 thereof.

Alkali and alkaline earth metal salts of phosphorus acids also are useful in the fuel compositions of the inven¬ tion. For example, the normal and basic salts of the phosphonic and/or thiophosphonic acids prepared by reacting inorganic phosphorus reagents such as P₂ ^S ₅ with petroleum fractions such as bright stock or polyolefins obtained from olefins of 2 to 6 carbon atoms. Particular examples of the polyolefins are polybutenes having a molecular weight of from 700 to 100,000. Other phosphorus-containing reagents which have been reacted with olefins include phosphorus trichloride or phosphorus trichloride-sulfur chloride mixture, (e.g., U.S. Patent Nos. 3,001,981 and 2,195,517), phosphites and phosphite chlorides (e.g., U.S. Patent Nos. 3,033,890 and 2,863,834), and air or oxygen with a phosphorus halide (e.g., U.S. Patent No. 2,939,841).

Other patents describing phosphorus acids and metal salts useful in the present invention and which are prepared by reacting olefins with phosphrous sulfides include the following U.S. Patents: 2,316,078; 2,316,079; 2,316,080; 2,316,081; 2,316,082; 2,316,085; 2,316,088; 2,375,315; 2,406,575; 2,496,508; 2,766,206; 2,838,484; 2,893,959 and 2,907,713. These acids which are described in the above patents as being oil additives, are useful in the fuel composition of the present invention. The acids can be converted to neutral and basic salts by reactions which are well known in the art.

Mixtures of two or more neutral and basic salts of the hereinabove described organic sulfur acids, carboxylic acids, phosphorus acids and phenols can be used in the compositions of this invention. Usually the neutral and basic salts will be sodium, lithium, magnesium, calcium, or barium salts including mixtures of two or more of any of these.

As mentioned above, the amount of alkali or alkaline earth metal containing composition (A) included in the fuel composition will be an amount which is sufficient to provide from about 1 to about 100 parts per million of the alkali metal or alkaline earth metal in the fuel composition. When utilized in lead free or low lead fuels, the amount of alkali metal or alkaline earth metal-containing composition (A) included in the fuel is an amount which is sufficient to reduce valve seat recession when the fuel is used in an internal combustion engine.

The following specific examples describe the preparation of exemplary alkali and alkaline earth metal compositions (A) useful in the fuel compositions of this invention. Example A-l

A mixture of 1000 parts of a primary branched sodium monoalkyl benzene sulfonate (M.W. of the acid is 522) in 637 parts of mineral oil is neutralized with the 145.7 parts of a 50% caustic soda solution and the excess water and caustic removed. The product containing the sodium salt obtained in this manner contains 2.5% sodium and 3.7% sulfur. Example A-2

The procedure of Example A-l is repeated except that the caustic soda is replaced by a chemically equivalent amount of Ca(OH)₂. Example A-3

The procedure of Example A-l is repeated except that the caustic soda is replaced by a chemically equivalent amount of KOH. Example A-4

A mixture of 906 parts of an alkyl phenyl sulfonic acid (having an average molecular weight of 450, vapor phase osmometry) , 564 parts mineral oil, 600 parts toluene, 98.7 parts magnesium oxide and 120 parts water is blown with carbon dioxide at a temperature of 78-85^βC for seven hours at a rate of about 3 cubic feet of carbon dioxide per hour (85 1/hr) . The reaction mixture is constantly agitated through¬ out the carbonation. After carbonation, the reaction mixture is stripped to 165°C/20 torr (2.65 KPa) and the residue filtered. The filtrate is an oil solution of the desired overbased magnesium sulfonate having a metal^" ratio of about 3. Example A-5

A mixture of 323 parts of mineral oil, 4.8 parts of water, 0.74 parts of calcium chloride, 79 parts of lime, and 128 parts of methyl alcohol is prepared, and warmed to a temperature of about 50°C. To this mixture there is added with mixing, 1000 parts of an alkyl phenyl sulfonic acid having an average molecular weight (vapor phase osmometry) of 500. The mixture then is blown with carbon dioxide at a temperature of about 50°C at the rate of about 5.4 lbs. per hour (40.8g/minute) for about 2.5 hours. After carbonation, 102 additional parts of oil are added and the mixture is stripped of volatile materials at a temperature of about 150-155°C at 55 mm (7.3 KPa) pressure. The residue is filtered and the filtrate is the desired oil solution of the overbased calcium sulfonate having calcium content of about 3.7% and a metal ratio of about 1.7.

The Hydrocarbon-Soluble Ashless Dispersant

The fuel compositions of the present invention desirably also contain a minor amount of at least one hydrocarbon soluble ashless dispersant (B) . The compounds useful as ashless dispersants generally are characterized by a "polar" group attached to a relatively high molecular weight hydro¬ carbon chain. The "polar" group generally contains one or more of the elements nitrogen, oxygen and phosphorus. The solubilizing chains are generally higher in molecular weight than those employed with the metallic types, but in some instances they may be quite similar.

In general, any of the ashless detergents which are known in the art for use in lubricants and fuels can be utilized in the fuel compositions of the present invention.

In one embodiment of the present invention, the disper¬ sant is selected from the group consisting of

(i) at least one hydrocarbyl-substituted amine wherein the hydrocarbyl substituent is substantially aliphatic and contains at least 8 carbon atoms;

(ii) at least one acylated, nitrogen-containing compound having a substituent of at least 10 aliphatic carbon atoms made by reacting a carboxylic acid acylating agent with at least one amino compound containing at least one

-NH- group, said acylating agent being linked to said amino compound through an imido, amido, amidine, or acyloxy ammoni¬ um linkage;

(iii) at least one nitrogen-containing condensate of a phenol, aldehyde and amino compound having at least one

-NH- group;

(iv) at least one ester of a substituted carboxylic acid;

(v) at least one polymeric dispersant;

(vi) at least one hydrocarbon substituted phenolic dispersant; and

(vii) at least one fuel soluble alkoxylated derivative of an alcohol, phenol or a ine.

The Hvdrocarbyl-Substituted Amine The hydrocarbyl-substituted amines used in the fuel compositions of this invention are well known to those of skill in the art and they are described in a number of patents. Among these are U.S. Patents 3,275,554; 3,438,757; 3,454,555; 3,565,804; 3,755,433 and 3,822,209. These patents disclose suitable hydrocarbyl amines for use in the present invention including their method of preparation.

A typical hydrocarbyl amine has the general formula: [AXN]_χ[-N([-UN-]_a[-UQ]_b)]_yR² _cH_1+2y+ay__c Formula IX wherein A is hydrogen, a hydrocarbyl group of from 1 to about 10 carbon atoms, or hydroxyhydrocarbyl group of from 1 to 10 carbon atoms; X is hydrogen, a hydrocarbyl group of from 1 to 10 carbon atoms, or hydroxyhydrocarbyl group of from 1 to 10 carbon atoms, and may be taken together with A and N to form a ring of from 5 to 6 annular members and up to 12 carbon atoms; U is an alkylene group of from 2 to 10 carbon atoms, any necessary hydrocarbons to accommodate the trivalent nitrogens are implied herein, R 2 is an aliphatic hydrocarbon of from about 30 to 400 carbon atoms; Q is a piperazine structure; a is an integer of from 0 to 10; b is an integer of from 0 to 1; a+2b is an integer of from 1 to 10; c is an integer of from about 1 to 5 and is an average in the range of 1 to 4, and equal to or less than the number of nitrogen atoms in the mole-cule; x is an integer of from 0 to 1; y is an integer of from about 0 to 1; and x+y is equal to 1.

In interpreting this formula, it is to be understood

2 that the R and H atoms are attached to the unsatisfied nitrogen valences within the brackets of the formula. Thus, for example, the formula includes sub-generic formulae wherein the R is attached to terminal nitrogens and isomeric subgeneric formula wherein it is attached to non-terminal nitrogen atoms. Nitrogen atoms not attached to an R 2 may bear a hydrogen or an AXN substituent.

The hydrocarbyl amines useful in this invention and embraced by the above formula include monoamines of the general formula:

AXNR² Formula X

Illustrative of such monoamines are the following: poly(propylene)amine N,N-dimethyl-n-poly(ethylene/propylene)amine

(50:50 mole ratio of monomers) poly(isobutene)amine

N,N-di( ydroxyethyl)-N-poly(isobutene)amine poly(isobutene/l-butene/2-butene)amine

(50:25:25 mole ratio of monomer) N-(2-hydroxyethyl)-N-poly(isobutene)amine N-(2-hydroxypropyl)-N-poly(isobutene)amine N-poly(1-butene)-aniline N-poly(isobutene)-morpholine Among the hydrocarbyl amines embraced by the general Formula IX as set forth above, are polya ines of the general formula:

-N([-UN-]_a[-UQ]_b)R² _cH_1+2y+ay__c Formula XI

Illustrative of such polyamines are the following: N-poly(isobutene) ethylene diamine N-poly(propylene) trimethylene diamine N-poly(1-butene) diethylene triamine N' ,N'-poly(isobutene) tetraethylene pentamine N,N-dimethyl-N'-poly(propylene) , 1,3-propylene diamine

The hydrocarbyl substituted amines useful in the fuel compositions of this invention include certain N-amino- hydrocarbyl morpholines which are not embraced in the general

Formula IX above. These hydrocarbyl-substituted aminohydro- carbyl morpholines have the general formula: R²N(A)UM Formula XII wherein R is an aliphatic hydrocarbon group of from about 30 to about 400 carbons, A is hydrogen, hydrocarbyl of from 1 to 10 carbon atoms or hydroxy hydrocarbyl group of from 1 to 10 carbon atoms, U is an alkylene group of from 2 to 10 carbon atoms, and M is a morpholine structure. These hydrocarbyl- substituted aminohydrocarbyl morpholines as well as the polyamines described by Formula X are among the typical hydrocarbyl-substituted amines used in preparing compositions of this invention.

The Acylated Nitro en-Containinσ Compounds

A number of acylated, nitrogen-containing compounds having a substituent of at least 10 aliphatic carbon atoms and made by reacting a carboxylic acid acylating agent with an amino compound are known to those skilled in the art. In such compositions the acylating agent is linked to the amino compound through an imido, amido, amidine or acyloxy ammonium linkage. The substituent of 10 aliphatic carbon atoms may be in either the carboxylic acid acylating agent derived portion of the molecule or in the amino compound derived portion of the molecule. Preferably, however, it is in the acylating agent portion. The acylating agent can vary from formic acid and its acylating derivatives to acylating agents having high molecular weight aliphatic substituents of up to 5,000, 10,000 or 20,000 carbon atoms. The amino compounds can vary from ammonia itself to amines having aliphatic substituents of up to about 30 carbon atoms.

A typical class of acylated amino compounds useful in the compositions of this invention are those made by reacting an acylating agent having an aliphatic substituent of at least 10 carbon atoms and a nitrogen compound characterized by the presence of at least one -NH- group. Typically, the acylating agent will be a mono- or polycarboxylic acid (or reactive equivalent thereof) such as a substituted succinic or propionic acid and the amino compound will be a polyamine or mixture of polyamines, most typically, a mixture of ethylene polyamines. The amine also may be a hydroxyalkyl- substituted polyamine. The aliphatic substituent in such acylating agents preferably averages at least about 30 or 50 and up to about 400 carbon atoms.

Illustrative hydrocarbon based groups containing at least ten carbon atoms are n-decyl, n-dodecyl, tetra-pro- penyl, n-octadecyl, oleyl, chlorooctadecyl, tri-icontanyl, etc. Generally, the hydrocarbon-based substituents are made from homo- or interpolymers (e.g., copolymers, terpolymers) of mono- and di-olefins having 2 to 10 carbon atoms, such as ethylene, propylene, butene-1, isobutene, butadiene, isoprene, 1-hexene, 1-octene, etc. Typically, these olefins are 1-monoolefins. The substituent can also be derived from the halogenated (e.g., chlorinated or brominated) analogs of such homo- or interpolymers. The substituent can, however, be made from other sources, such as monomeric high molecular weight alkenes (e.g., 1-tetracontene) and chlorinated analogs and hydrochlorinated analogs thereof, aliphatic petroleum fractions, particularly paraffin waxes and cracked and chlorinated analogs and hydrochlorinated analogs thereof, white oils, synthetic alkenes such as those produced by the Ziegler-Natta process (e.g., poly(ethylene) greases) and other sources known to those skilled in the art. Any unsaturation in the substituent may be reduced or eliminated by hydrogenation according to procedures known in the art.

As used in this specification and appended claims, the term "hydrocarbon-based" denotes a group having a carbon atom directly attached to the remainder of the molecule and having a predominantly hydrocarbon character within the context of this invention. Therefore, hydrocarbon-based groups can contain up to one non-hydrocarbon group for every ten carbon atoms provided this non-hydrocarbon group does not signifi¬ cantly alter the predominantly hydrocarbon character of the group. Those skilled in the art will be aware of such groups, which include, for example, hydroxyl, halo (especial¬ ly chloro and fluoro) , alkoxyl, alkyl mercapto, alkyl sulfoxy, etc. Usually, however, the hydrocarbon-based substituents are purely hydrocarbyl and contain no such non-hydrocarbyl groups.

The hydrocarbon-based substituents are substantially saturated, that is, they contain no more than one carbon- to-carbon unsaturated bond for every ten carbon-to-carbon single bonds present. Usually, they contain no more than one carbon-to-carbon non-aromatic unsaturated bond for every 50 carbon-to-carbon bonds present.

The hydrocarbon-based substituents are also substan¬ tially aliphatic in nature, that is, they contain no more than one non-aliphatic moiety (cycloalkyl, cycloalkenyl or aromatic) group of six or less carbon atoms for every ten carbon atoms in the substituent. Usually, however, the substituents contain no more than one such non-aliphatic group for every fifty carbon atoms, and in many cases, they contain no such non-aliphatic groups at all; that is, the typical substituents are purely aliphatic. Typically, these purely aliphatic substituents are alkyl or alkenyl groups.

Specific examples of the substantially saturated hydro¬ carbon-based substituents containing an average of more than 30 carbon atoms are the following: a mixture of poly(ethylene/propylene) groups of about 35 to about 70 carbon atoms a mixture of the oxidatively or mechanically degraded poly(ethylene/propylene) groups of about 35 to about 70 carbon atoms a mixture of poly(propylene/l-hexene) groups of about 80 to about 150 carbon atoms a mixture of poly(isobutene) groups having an average of 50 to 75 carbon atoms.

A preferred source of the substituents are poly(isobutene)s obtained by polymerization of a C refinery stream having a butene content of 35 to 75 weight percent and isobutene content of 30 to 60 weight percent in the presence of a Lewis acid catalyst such as aluminum trichloride or boron tri- fluoride. These polybutenes contain predominantly (greater than 80% of total repeating units) isobutene repeating units of the configuration: -C(CH₃)₂CH₂- Exemplary of amino compounds useful in making these acylated compounds are the following:

(1) polyalkylene polyamines of the general formu¬ la:

(R³)₂N[U-N(R³)]_nR³ Formula XIII wherein each R is independently a hydrogen atom, a hydrocarbyl group or a hydroxy-substituted hydrocarbyl group containing up to about 30 carbon atoms, with proviso that at least one R 3 is a hydrogen atom, n is a whole number of 1 to

10 and U is a C 1.—.lo_ alkylene group, (2) heterocyclic-substi- tuted polyamines including hydroxyalkyl-substituted poly¬ amines wherein the polyamines are described above and the heterocyclic substituent is e.g., a piperazine, an imidazo- line, a pyrimidine, a morpholine, etc., and (3) aromatic polyamines of the general formula:

Ar(NR³ __)y Formula XIV wherein Ar is a aromatic nucleus of 6 to about 20 carbon atoms, each R' " is as defined hereinabove and y is 2 to about 8. Specific examples of the polyalkylene polyamines (1) are ethylene diamine, tetra(ethylene)pentamine, tri- (tri ethylene)tetramine, 1,2-propylene diamine, etc. Spe¬ cific examples of hydroxyalkyl-substituted polyamines include N-(2-hydroxyethyl) ethylene diamine, N,N'-bis-(2-hydroxy- ethyl) ethylene diamine, N-(3-hydroxybutyl) tetramethylene diamine, etc. Specific examples of the heterocyclic-substi- tuted polyamines (2) are N-2-aminoethyl piperazine, N-2 and N-3 amino propyl morpholine, N-3(di-methyl amino) propyl piperazine, 2-heptyl-3-(2-aminopropyl) imidazoline, 1,4-bis (2-aminoethyl) piperazine, l-(2-hydroxy ethyl) piperazine, and 2-heptadecyl-l-(2-hydroxyethyl)-imidazoline, etc. Specific examples of the aromatic polyamines (3) are the various isomeric phenylene diamines, the various isomeric naphthalene diamines, etc.

Many patents have described useful acylated nitrogen compounds including U.S. Patents 3,172,892; 3,219,666; 3,272,746; 3,310,492; 3,341,542; 3,444,170; 3,455,831; 3,455,832; 3,576,743; 3,630,904; 3,632,511; 3,804,763 and 4,234,435. A typical acylated nitrogen-containing compound of this class is that made by reacting a poly(isobutene)- substituted succinic anhydride acylating agent (e.g., anhy¬ dride, acid, ester, etc.) wherein the poly(isobutene) substi¬ tuent has between about 50 to about 400 carbon atoms with a mixture of ethylene polyamines having 3 to about 7 amino nitrogen atoms per ethylene polyamine and about 1 to about 6 ethylene chloride. In view of the extensive disclosure of this type of acylated amino compound, further discussion of their nature and method of preparation is not needed here. The above-noted U.S. Patents are utilized for their dis¬ closure of acylated amino compounds and their method of preparation.

Another type of acylated nitrogen compound belonging to this class is that made by reacting the afore-described alkylene amines with the afore-described substituted succinic acids or anhydrides and aliphatic mono-carboxylic acids having from 2 to about 22 carbon atoms. In these types of acylated nitrogen compounds, the mole ratio of succinic acid to mono-carboxylic acid ranges from about 1:0.1 to about 1:1. Typical of the mono-carboxlyic acid are formic acid, acetic acid, dodecanoic acid, butanoic acid, oleic acid, stearic acid, the commercial mixture of stearic acid isomers known as isostearic acid, tolyl acid, etc. Such materials are more fully described in U.S. Patents 3,216,936 and 3,250,715.

Still another type of acylated nitrogen compound useful in making the fuels of this invention is the product of the reaction of a fatty monocarboxylic acid of about 12-30 carbon atoms and the afore-described alkylene amines, typically, ethylene, propylene or trimethylene polyamines containing 2 to 8 amino groups and mixtures thereof. The fatty mono- carboxylic acids are generally mixtures of straight and branched chain fatty carboxylic acids containing 12-30 carbon atoms. A widely used type of acylated nitrogen compound is made by reacting the afore-described alkylene polyamines with a mixture of fatty acids having from 5 to about 30 mole percent straight chain acid and about 70 to about 95 percent mole branched chain fatty acids. Among the commercially available mixtures are those known widely in the trade as isostearic acid. These mixtures are produced as a by-product from the dimerization of unsaturated fatty acids as described in U.S. Patents 2,812,342 and 3,260,671.

The branched chain fatty acids can also include those in which the branch is not alkyl in nature, such as found in phenyl and cyclohexyl stearic acid and the chlorostearic acids. Branched chain fatty carboxylic acid/alkylene polyamine products have been described extensively in the art. See for example, U.S. Patents 3,110,673; 3,251,853; 3,326,801; 3,337,459; 3,405,064; 3,429,674; 3,468,639; 3,857,791. These patents are utilized for their disclosure of fatty acid/polyamine condensates for their use in lubri¬ cating oil formulations.

The Nitroσen-Containinσ Condensates of Phenols. Aldehydes, and Amino Compounds

The phenol/aldehyde/amino compound condensates useful as dispersants in the fuel compositions of this invention include those generically referred to as Mannich conden¬ sates. Generally they are made by reacting simultaneously or sequentially at least one active hydrogen compound such as a hydrocarbon-substituted phenol (e.g., and alkyl phenol wherein the alkyl group has at least an average of about 12 to 400; preferably 30 up to about 400 carbon atoms), having at least one hydrogen atom bonded to an aromatic carbon, with at least one aldehyde or aldehyde-producing material (typi¬ cally a formaldehyde precursor) and at least one amino or polyamino compound having at least one NH group. The amino compounds include primary or secondary monoamines having hydrocarbon substituents of 1 to 30 carbon atoms or hydroxyl- substituted hydrocarbon substituents of 1 to about 30 carbon atoms. Another type of typical amino compound are the polyamines described during the discussion of the acylated nitrogencontaining compounds.

Exemplary mono-amines include methyl ethyl amine, methyl octadecyl amines, aniline, diethyl amine, diethanol amine, dipropyl amine and so forth. The following U.S. Patents contain extensive descriptions of Mannich condensates which can be used in making the compositions of this invention:

U.S. PATENTS 2,459,112 3,413,347 3,558,743 2,962,442 3,442,808 3,586,629 2,984,550 3,448,047 3,591,598 3,036,003 3,454,497 3,600,372 3,166,516 3,459,661 3,634,515 3,236,770 3,461,172 3,649,229 3,355,270 3,493,520 3,697,574 3,368,972 3,539,633 Condensates made from sulfur-containing reactants also can be used in the fuel compositions of the present inven¬ tion. Such sulfur-containing condensates are described in U.S. Patents 3,368,972; 3,649,229; 3,600,372; 3,649,659 and 3,741,896. These patents also disclose sulfur-containing Mannich condensates. Generally the condensates used in making compositions of this invention are made from a phenol bearing an alkyl substituent of about 6 to about 400 carbon atoms, more typically, 30 to about 250 carbon atoms. These typical condensates are made from formaldehyde or C___ aliphatic aldehyde and an amino compound such as those used in making the acylated nitrogen-containing compounds de¬ scribed under (B) (ii) .

These preferred condensates are prepared by reacting about one molar portion of phenolic compound with about 1 to about 2 molar portions of aldehyde and about 1 to about 5 equivalent portions of amino compound (an equivalent of amino compound is its molecular weight divided by the number of =NH groups present) . The conditions under which such condensa¬ tion reactions are carried out are well known to those skilled in the art as evidenced by the above-noted patents. Therefore, these patents are also incorporated by reference for their disclosures relating to reaction conditions.

A particularly preferred class of nitrogen-containing condensation products for use in the fuels of the present invention are those made by a "2-step process" as disclosed in commonly assigned U.S. Serial No. 451,644, filed March 15, 1974 now abandoned. Briefly, these nitrogen-containing condensates are made by (1) reacting at least one hydroxy aromatic compound containing an aliphatic-based or cycloaliphatic-based substituent which has at least about 30 carbon atoms and up to about 400 carbon atoms with a lower aliphatic C, _ aldehyde or reversible polymer thereof in the presence of an alkaline reagent, such as an alkali metal hydroxide, at a temperature up to about 150°C; (2) substan¬ tially neutralizing the intermediate reaction mixture thus formed; and (3) reacting the neutralized intermediate with at least one compound which contains an amino group having at least one -NH- group.

More preferably, these 2-step condensates are made from (a) phenols bearing a hydrocarbon-based substituent having about 30 to about 250 carbon atoms, said substituent being derived from a polymer of propylene, 1-butene, 2-butene, or isobutene and (b) formaldehyde, or reversible polymer there¬ of, (e.g., trioxane, paraformaldehyde) or functional equiva¬ lent thereof, (e.g., methylol) and (c) an alkylene polyamine such as ethylene polyamines having between 2 and 10 nitrogen atoms. Further details as to this preferred class of conden¬ sates can be found in the hereinabove noted U.S. Serial No. 451,644, which is hereby incorporated by reference, for its disclosures relating to 2-step condensates.

The Esters of Substituted Carboxylic Acids

The esters useful as detergents/dispersants in this invention are derivatives of substituted carboxylic acids in which the substituent is a substantially aliphatic, substan¬ tially saturated hydrocarbon-based group containing at least about 30 (preferably about 50 to about 750) aliphatic carbon atoms. As used herein, the term "hydrocarbon-based group" denotes a group having a carbon atom directly attached to the remainder of the molecule and having predominantly hydrocar¬ bon character within the context of this invention. Such groups include the following:

(1) Hydrocarbon groups; that is, aliphatic groups, aromatic- and alicyclic-substituted aliphatic groups, and the like, of the type known to those skilled in the art.

(2) Substituted hydrocarbon groups; that is, groups containing non-hydrocarbon substituents which, in the context of this invention, do not alter the predominantly hydrocarbon character of the group. Those skilled in the art will be aware of suitable substituents; examples are halo, nitro, hydroxy, alkoxy, carbalkoxy and alkylthio.

(3) Hetero groups; that is, groups which, while predominantly hydrocarbon in character within the context of this invention, contain atoms other than carbon present in a chain or ring otherwise composed of carbon atoms. Suitable hetero atoms will be apparent to those skilled in the art and include, for example, nitrogen, oxygen and sulfur.

In general, no more than about three substituents or hetero atoms, and preferably no more than one, will be present for each 10 carbon atoms in the hydrocarbon-based group.

The substituted carboxylic acids (and derivatives thereof including esters, amides and imides) are normally prepared by the alkylation of an unsaturated acid, or a derivative thereof such as an anhydride, ester, amide or imide, with a source of the desired hydrocarbon-based group. Suitable unsaturated acids and derivatives thereof include acrylic acid, methacrylic acid, maleic ^' acid, maleic anhydride, fumaric acid, itaconic acid, itaconic anhydride, citraconic acid, citraconic anhydride, mes-aconic acid, glutaconic acid, chloromaleic acid, aconitic acid, crotonic acid, methylcrotonic acid, sorbic acid, 3-hexenoic acid, 10-decenoic acid and 2-pentene-l,3,5-tri-carboxylic acid. Particularly preferred are the unsaturated dicarboxylic acids and their derivatives, especially maleic acid, fumaric acid and maleic anhydride.

Suitable alkylating agents include homopolymers and interpolymers of polymerizable olefin monomers containing from about 2 to about 10 and usually from about 2 to about 6 carbon atoms, and polar substituent-containing derivatives thereof. Such polymers are substantially saturated (i.e., they contain no more than about 5% olefinic linkages) and substantially aliphatic (i.e., they contain at least about 80% and preferably at least about 95% by weight of units derived from aliphatic mono-olefins) . Illustrative monomers which may be used to produce such polymers are ethylene, propylene, 1-butene, 2-butene, isobutene, 1-octene and 1-decene. Any unsaturated units may be derived from conju¬ gated dienes such as 1,3-buta-diene and isoprene; non-conju¬ gated dienes such as 1,4-hexadiene, 1,4-cyclohexadiene, 5-ethylidene-2-norbornene and 1,6-octadiene: and trienes such as l-isopropylidene-3a,4,7,-7a-tetrahydroindene, 1-isopro- pylidene-dicyclopentadiene and 2-(2-methylene-4-methyl-3- pentenyl) [2.2.l]bicyclo-5-heptene.

A first preferred class of polymers comprises those of terminal olefins such as propylene, 1-butene, isobutene and 1-hexene. Especially preferred within this class are polybutenes comprising predominantly isobutene units. A second preferred class comprises terpolymers of ethylene, a c_ alpha-monoolefin and a polyene selected from the group consisting of non-conjugated dienes (which are especially preferred) and trienes. Illustrative of these terpolyers is "Ortholeum 2052" manufactured by E.I duPont de Nemours & Company, which is a terpolymer containing about 48 mole percent ethylene groups, 48 mole percent propylene groups and 4 mole percent 1,4-hexadiene groups and having an inherent viscosity of 1.35 (8.2 grams of polymer in 10 ml. of carbon tetrachloride at 30°C).

Methods for the preparation of the substituted car¬ boxylic acids and derivatives thereof are well known in the art and need not be described in detail. Reference is made, for example, to U.S. Patents 3,272,746; 3,522,179; and 4,234,435 which are incorporated by reference herein. The mole ratio of the polymer to the unsaturated acid or deriva¬ tive thereof may be equal to, greater than or less than 1, depending on the type of product desired.

The esters are those of the above-described succinic acids with hydroxy compounds which may be aliphatic compounds such as monohydric and polyhydric alcohols or aromatic compounds such as phenols and naphthols. The aromatic hydroxy compounds from which the esters of this invention may be derived are illustrated by the following specific exam¬ ples: phenol, beta-naphthol, alpha-naphthol, cresol, resorcinol, catechol, p,p'di-hydroxybiphenyl, 2-chlorophenol, 2,4-dibutylphenol, propene tetramer-substituted phenol, didodecylphenol, 4,4'-methylene-bis-phenol, alpha-decyl- beta-naphthol, polyisobutene (molecular weight of 1000)-sub¬ stituted phenol, the condensation product of heptylphenol with 0.5 mole of formaldehyde, the condensation product of octyl-phenol with acetone, di(hydroxyphenyl)-oxide, di(hy- droxyphenyl)sulfide, di(hydroxyphenyl)disulfide, and 4-cyclo- hexylphenol. Phenol and alkylated phenols having up to three alkyl substituents are preferred. Each of the alkyl substi¬ tuents may contain 100 or more carbon atoms.

The alcohols from which the esters may be derived preferably contain up to about 40 aliphatic carbon atoms. They may be monohydric alcohols such as methanols, ethanol, isooctanol, dodecanol, cyclohexanol, cyclopentanol, behenyl alcohol, hexatriacontanol, neopentyl alcohol, isobutyl alcohol, benzyl alcohol, beta-phenylethyl alcohol, 2-methylσyclohexanol, beta-chloroethanol, monomethyl ether of ethylene glycol, monobutyl ether of ethylene glycol, monopropyl ether of diethylene glycol, monododecyl ether of triethylene glycol, monooleate of ethylene glycol, monostearate of diethylene glycol, secpentyl alcohol, tertbutyl alcohol, 5-bromo-dodecanol, nitro-octadecanol and dioleate of glycerol. The polyhydric alcohols preferably contain from 2 to about 10 hydroxy radicals. They are illustrated by, for example, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, dibutylene glycol, tri-butylene glycol, and other alkylene glycols in which the alkylene radical contains from 2 to about 8 carbon atoms. Other useful polyhydric alcohols include glycerol, mono-oleate of glycerol, monostearate of glycerol, monomethyl ether of glycerol, pentaerythritol, 9,10-dihydroxy stearic acid, methyl ester of 9,10-dihydroxy stearic acid, 1,2-butanediol, 2,3-hexanediol, 2,4-hexanediol, penacol, erythritol, arabitol, sorbitol, mannitol, 1,2-cyclo-hexanediol, and xylene glycol. Carbohydrates such as sugars, starches, cellulose, etc. , likewise may yield the esters of this inven¬ tion. The carbohydrates may be exemplified by a glucose, fructose, sucrose, rhamnose, mannose, glyceraldehyde, and galactose.

An especially preferred class of polyhydric alcohols are those having at least three hydroxy radicals, some of which have been esterified with a monocarboxylic acid having from about 8 to about 30 carbon atoms, such as octanoic acid, oleic acid, stearic acid, linoleic acid, dodecanoic acid, or tall oil acid. Examples of such partially esterified polyhydric alcohols are the mono-oleate of sorbitol, distearate of sorbitol, monooleate of glycerol, monostearate of glycerol, di-dodecanoate of erythritol.

The esters may also be derived from unsaturated alcohols such as allyl alcohol, cinnamyl alcohol, propargyl alcohol, l-cyclohexene-3-ol, an oleyl alcohol. Still another class of the alcohols capable of yielding the esters of this invention comprise the ether-alcohols and amino-alcohols including, for example, the oxyalkylene-, oxyarylene-, amino^'-alkylene-, and amino-arylene-substituted alcohols having one or more oxy¬ alkylene, amino-alkylene or amino-arylene oxy-arylene radi¬ cals. They are exemplified by Cellosolve, carbitol, phenoxy- ethanol, heptylphenyl-(oxypropylene) ,-H, octyl-(oxyethy¬ lene)_3Q-H, phenyl-(oxyoctylene)₂ ^_H, mono(heptylphenyl- oxypropylene)-substituted glycerol, poly(styrene oxide), amino-ethanol, 3-amino ethyl-pentanol, di(hydroxyethyl) amine, p-amino-phenol, tri(hydroxypropyl)amine, N-hydroxy- ethyl ethylene diamine, N,N,N' ,N'-tetrahydroxy-trimethylene diamine, and the like. For the most part, the ether-alcohols having up to about 150 oxyalkylene radicals in which the alkylene radical contains from 1 to about 8 carbon atoms are preferred.

The esters may be di-esters of succinic acids or acidic esters, i.e., partially esterified polyhydric alcohols or phenols, i.e., esters having free alcoholic or phenolic hydroxyl radicals. Mixtures of the above-illustrated esters likewise are contemplated within the scope of the invention.

The esters may be prepared by one of several methods. The method which is preferred because of convenience and superior properties of the esters it produces, involves the reaction of a suitable alcohol or phenol with a substan¬ tially hydrocarbon-substituted succinic anhydride. The esterification is usually carried out at a temperature above o o o about 100 C, preferably between 150 C and 300 C.

The water formed as a by-product is removed by distilla¬ tion as the esterification proceeds. A solvent may be used in the esterification to facilitate mixing and temperature control. It also facilitates the removal of water from the reaction mixture. The useful solvents include xylene, toluene, diphenyl ether, chlorobenzene, and mineral oil.

A modification of the above process involves the re¬ placement of the substituted succinic anhydride with the corresponding succinic acid. However, succinic acids readily o undergo dehydration at temperatures above about 100 C and are thus converted to their anhydrides which are then esterified by the reaction with the alcohol reactant. in this regard, succinic acids appear to be the substantial equivalent of their anhydrides in the process.

The relative proportions of the succinic reactant and the hydroxy reactant which are to be used depend to a large measure upon the type of the product desired and the number of hydroxyl groups present in the molecule of the hydroxy reactant. For instance, the formation of a half ester of a succinic acid, i.e., one in which only one of the two acid radicals is esterified, involves the use of one mole of a monohydric alcohol for each mole of the substituted succinic acid reactant, whereas the formation of a diester of a succinic acid involves the use of two moles of the alcohol for each mole of the acid. On the other hand, one mole of a hexahydric alcohol may combine with as many as six moles of a succinic acid to form an ester in which each of the six hydroxyl radicals of the alcohol is esterified with one of the two acid radicals of the succinic acid. Thus, the maximum proportion of the succinic acid to be used with a polyhydric alcohol is determined by the number of hydroxyl groups present in the molecule of the hydroxy reactant. For the purposes of this invention, it has been found that esters obtained by the reaction of equimolar amounts of the succinic acid reactant and hydroxy reactant have superior properties and are therefore preferred.

In some instances, it is advantageous to carry out the esterification in the presence of a catalyst such as sulfuric acid, pyridine hydrochloride, hydrochloric acid, benzene- sulfonic acid, p-toluenesulfonic acid, phosphoric acid, or any other known esterification catalyst. The amount of the catalyst in the reaction may be as little as 0.01% (by weight of the reaction mixture), more often from about 0.1% to about 5%.

The esters of this invention likewise may be obtained by the reaction of a substituted succinic acid or anhydride with an epoxide or a mixture of a epoxide and water. Such reaction is similar to one involving the acid or anhydride with a glycol. For instance, the product may be prepared by the reaction of a substituted succinic acid with one mole of ethylene oxide. Similarly, the product may be obtained by the reaction of a substituted succinic acid with two moles of ethylene oxide. Other epoxides which are commonly available for use in such reaction include, for example, propylene oxide, styrene oxide, 1,2-butylene oxide, 2,3-butylene oxide, epichlorohydrin, cyclohexene oxide, 1,2-octylene oxide, epoxidized soya bean oil, methyl ester of 9,10-epoxy-stearic acid, and butadiene mono-epoxide. For the most part, the epoxides are the alkylene oxides in which the alkylene radical has from 2 to about 8 carbon atoms; or the epoxidized fatty acid esters in which the fatty acid radical has up to about 30 carbon atoms and the ester radical is derived from a lower alcohol having up to about 8 carbon atoms.

In lieu of the succinic acid or anhydride, a lactone acid or a substituted succinic acid halide may be used in the processes illustrated above for preparing the esters of this invention. Such acid halides may be acid dibromides, acid dichlorides, acid monochlorides, and acid monobromides. The substituted succinic anhydrides and acids can be prepared by, for example, the reaction of maleic anhydride with a high molecular weight olefin or a halogenated hydrocarbon such as is obtained by the chlorination of an olefin polymer de¬ scribed previously. The reaction involves merely heating the o reactants at a temperature preferably from about 100 C to about 250 C. The product from such a reaction is an alkenyl succinic anhydride. The alkenyl group may be hydrogenated to an alkyl group. The anhydride may be hydrolyzed by treat¬ ment with water or steam to the corresponding acid. Another method useful for preparing the succinic acids or anhydrides involves the reaction of itaconic acid or anhydride with an olefin or a chlorinated hydrocarbon at a temperature usually o o within the range from about 100 C to about 250 C. The succinic acid halides can be prepared by the reaction of the acids or their anhydrides with a halogenation agent such as phosphorous tribromide, phosphorus pentachloride, or thionyl chloride. These and other methods of preparing the succinic compounds are well known in the art and need not be illus¬ trated in further detail here.

Still other methods of preparing the esters useful in the fuels of this invention are available. For instance, the esters may be obtained by the reaction of maleic acid or anhydride with an alcohol such as is illustrated above to form a mono- or di-ester of maleic acid and then the reaction of this ester with an olefin or a chlorinated hydrocarbon such as is illustrated above. They may also be obtained by first esterifying itaconic anhydride or acid and subsequently reacting the ester intermediate with an olefin or a chlori¬ nated hydrocarbon under conditions similar to those described hereinabove.

The Polymeric Dispersants

A large number of different types of polymeric disper¬ sants have been suggested as useful in lubricating oil formulations, and such polymeric dispersants are useful in the fuel compositions of the present invention. Often, such additives have been described as being useful in lubricating formulations as viscosity index improvers with dispersing characteristics. The polymeric dispersants generally are polymers or copolymers having a long carbon chain and con¬ taining "polar" compounds to impart the dispersancy charac¬ teristics. Polar groups which may be included include amines, amides, i ines, imides, hydroxyl, ether, etc. For example, the polymeric dispersants may be copolymers of methacrylates or acrylates containing additional polar groups, ethylene-propylene copolymers containing polar groups or vinyl acetate fumaric acid ester copolymers.

Many such polymeric dispersants have been described in the prior art, and it is not believed necessary to list in detail the various types. The following are examples of patents describing polymeric dispersants. U.S. Patent 4,402,844 describes nitrogen-containing copolymers prepared by the reaction of lithiated hydrogenated conjugated dienemonovinylarene copolymers with substituted amino- lactans. U.S. Patent 3,356,763 describes a process for producing block copolymers of dienes such as 1,3-butadiene and vinyl aromatic hydrocarbons such as ethyl styrenes. U.S. Patent 3,891,721 describes block polymers of styrene- butadiene-2-vinyl pyridine.

A number of the polymeric dispersants may be prepared by the grafting polar monomers to polyolefinic backbones. For example, U.S. Patent 3,687,849 and 3,687,905 describe the use of maleic anhydrides as a graft monomer to a polyolefinic backbone. Maleic acid or anhydride is particularly desirable as a graft monomer because this monomer is relatively inexpensive, provides an economical route to the incorpora¬ tion of dispersant nitrogen compounds into polymers by further reaction of the carboxyl groups of the maleic acid or anhydride with, for example, nitrogen compounds or hydroxy compounds. U.S. Patent 4,160,739 describes graft copolymers obtained by the grafting of a monomer system comprising maleic acid or anhydride and at least one other different monomer which is addition copolymerizable therewith, the grafted monomer system then being post-reacted with a polyamine. The monomers which are copolymerizable with maleic acid or anhydride are any alpha, beta-monoethylenical- ly unsaturated monomers which are sufficiently soluble in the reaction medium and reactive towards maleic acid or anhydride so that substantially larger amounts of maleic acid or anhydride can be incorporated into the grafted polymeric product. Accordingly, suitable monomers include the esters, amides and nitriles of acrylic and methacrylic acid, and monomers containing no free acid groups. The inclusion of heterocyclic monomers into graft polymers is described by a process which comprises a first step of graft polymerizing an alkyl ester of acrylic acid or methacrylic acid, alone or in combination with styrene, onto a backbone copolymer which is a hydrogenated block copolymer of styrene and a conjugated diene having 4 to 6 carbon atoms to form a first graft polymer. In the second step, a polymerizable heterocyclic monomer, alone or in combination with a hydro-phobizing vinyl ester is copolymerized onto the first graft copolymer to form a second graft copolymer.

Other patents describing graft polymers useful as dispersants in the fuels of this invention include U.S. Patents 3,243,481; 3,475,514; 3,723,575; 4,026,167; 4,085,055; 4,181,618; and 4,476,283.

Another class of polymeric dispersant useful in the fuel compositions of the invention are the so-called "star" polymers and copolymers. Such polymers are described in, for example, U.S. Patents 4,346,193, 4,141,847, 4,358,565, 4,409,120 and 4,077,893. All of the above patents relating to polymeric dispersants are utilized for their disclosure of suitable polymeric dispersants which can be utilized in the fuels of this invention.

The Hydrocarbon-Substituted Phenolic Dispersant

The hydrocarbon-substituted phenolic dispersants useful in the fuel compositions of the present invention include the hydrocarbon-substituted phenolic compounds wherein the hydrocarbon substituents have a molecular weight which is sufficient to render the phenolic compound fuel soluble. Generally, the hydrocarbon substituent will be a substan¬ tially saturated, hydrocarbon-based group of at least about 30 carbon atoms. The phenolic compounds may be represented generally by the following formula:

(R)_a-Ar-(OH)_b Formula XV wherein R is a substantially saturated hydrocarbon-based substituent having an average of from about 30 to about 400 aliphatic carbon atoms, and a and b are each, 1, 2 or 3. Ar is an aromatic moiety such as a benzene nucleus, naphthalene nucleus or linked benzene nuclei. Optionally, the above phenates as represented by Formula XV may contain other substituents such as lower alkyl groups, lower alkoxyl, nitro, amino, and halo groups. Preferred examples of option¬ al substituents are the nitro and amino groups.

The substantially saturated hydrocarbon-based group R in Formula XV may contain up to about 750 aliphatic carbon atoms although it usually has a maximum of an average of about 400 carbon atoms. In some instances R has a minimum of about 50 carbon atoms. As noted, the phenolic compounds may contain more than one R group for each aromatic nucleus in the aromatic moiety Ar.

Generally, the hydrocarbon-based groups R are made from homo- or interpolymers (e.g., copolymers, terpolymers) of mono- and di-olefins having 2 to 10 carbon atoms, such as ethylene, propylene, butene-1, isobutene, butadiene, isoprene, 1-hexene, 1-octene, etc. Typically, these olefins are 1-monoolefins. The R groups can also be derived from the halogenated (e.g., chlorinated or brominated) analogs of such homo- or interpolymers. The R groups can, however, be made from other sources, such as monomeric high molecular weight alkenes (e.g. 1-tetracontene) and chlorinated analogs and hydrochlorinated analogs thereof, aliphatic petroleum fractions, particularly paraffin waxes and cracked and chlorinated analogs and hydrochlorinated analogs thereof, white oils, synthetic alkenes such as those produced by the Ziegler-Natta process (e.g., polyethylene greases) and other sources known to those skilled in the art. Any unsaturation in the R groups may be reduced or eliminated by hydrogenation according to procedures known in the art before the nitration step described hereafter.

Specific examples of the substantially saturated hydro¬ carbon-based R groups are the following: a tetracontanyl group a henpentacontanyl group a mixture of poly(ethylene/propylene) groups of about 35 to about 70 carbon atoms a mixture of the oxidatively or mechanically degraded poly-(ethylene/propylene) groups of about 35 to about 70 carbon atoms a mixture of poly(propylene/1-hexene) groups of about 80 to about 150 carbon atoms a mixture of poly(isobutene) groups having between 20 and 32 carbon atoms a mixture of poly(isobutene) groups having an average of 50 to 75 carbon atoms. A preferred source of the group R are poly-(isobutene)s obtained by polymerization of a C. refinery stream having a butene content of 35 to 75 weight percent and isobutene content of 30 to 60 weight percent in the presence of a Lewis acid catalyst such as aluminum trichloride or boron tri- fluoide. These polybutenes contain predominantly (greater than 80% of total repeat units) isobutene repeating units of the configuration

-C(CH₃)₂CH₂- . The attachment of the hydrocarbon-based group R to the aromatic moiety Ar of the amino phenols of this invention can be accomplished by a number of techniques well known to those skilled in the art.

In one preferred embodiment, the phenolic dispersants useful in the fuels of the present invention are hydrocar¬ bon-substituted nitro phenols as represented by Formula XV wherein the optional substituent is one or more nitro groups. The nitro phenols can be conveniently prepared by nitrating appropriate phenols, and typically, the nitro phenols are formed by nitration of alkyl phenols having an alkyl group of at least about 30 and preferably about 50 carbon atoms. The preparation of a number of hydrocarbon-substituted nitro phenols useful in the fuels of the present invention is described in U.S. Patent 4,347,148.

In another preferred embodiment, the hydrocarbon-sub¬ stituted phenol dispersants useful in the present invention are hydrocarbon-substituted amino phenols such as represented by Formula XV wherein the optional substituent is one or more amino groups. These amino phenols can conveniently be prepared by nitrating an appropriate hydroxy aromatic com¬ pound as described above and there after reducing the nitro groups to amino groups. Typically, the useful amino phenols are formed by nitration and reduction of alkyl phenols having an alkyl or alkenyl group of at least about 30 and preferably about 50 carbon atoms. The preparation of a large number of hydrocarbon-substituted amino phenols useful as dispersants in the present invention is described in U.S. Patent 4,320,021.

The Fuel-Soluble Alkoxylated Derivatives of Alcohols, Phenols or Amines

Also useful as dispersants in the fuel compositions of the present invention are fuel-soluble alkoxylated deriva¬ tives of alcohols, phenols and amines. A wide variety of such derivatives can be utilized as long as the derivatives are fuel-soluble. More preferably, the derivatives in addition to being fuel-soluble should be water-insoluble. Accordingly, in a preferred embodiment, the fuel-soluble alkoxylated derivatives useful as the dispersants are characterized as having an HLB of from 1 to about 13.

As is well known to those skilled in the art, the fuel-solubility and water-insolubility characteristics of the alkoxylated derivatives can be controlled by selection of the alcohol or phenols and amines, selection of the particular alkoxy reactant, and by selection of the amount of alkoxy reactant which is reacted with the alcohols, phenols and amines. Accordingly, the alcohols which are utilized to prepare the alkoxylated derivatives are hydrocarbon based alcohols while the amines are hydrocarbyl-substituted amines such as, for example, the hydrocarbyl-substituted amines described above as dispersant (B) (i) . The phenols may be phenols or hydrocarbon-substituted phenols and the hydrocar¬ bon substituent may contain as few as 1 carbon atom.

The alkoxylated derivatives are obtained by reacting the alcohol, phenol or amine with an epoxide or a mixture of an epoxide and water. For example, the derivative may be prepared by the reaction of the alcohol, phenol or amine with an equal molar amount or an excess of ethylene oxide. Other epoxides which can be reacted with the alcohol, phenol or amine include, for example, propylene oxide, styrene oxide, 1,2-butylene oxide, 2,3-butylene oxide, epichlorohydrin, cyclohexene oxide, 1,2-octylene oxide, etc. Preferably, the epoxides are the alkylene oxides in which the alkylene group has from about 2 to about 8 carbon atoms. As mentioned above, it is desirable and preferred that the amount of alkylene oxide reacted with the alcohol, phenol or amine be insufficient to render the derivative water-soluble.

The following are examples of commercially available alkylene oxide derivatives which may be utilized as disper¬ sants in the fuel compositions of the present invention: Etho een S/12, tertiary amines ethylene oxide condensation products of the primary fatty amines (HLB, 4.15; Armak Industries); Plurafac A-24, an oxyethylated straight-chain alcohol available from BASF Wyandotte Industries (HLB 5.0); etc. Other suitable fuel-soluble alkoxylated derivatives of alcohols, phenols and amines will be readily apparent to those skilled in the art.

The following specific examples illustrate the prepara¬ tion of exemplary dispersants useful in the fuel compositions of this invention.

Example B-l

A mixture of 1500 parts of chlorinated poly-(isobutene) having a molecular weight of about 950 and a chlorine content of 5.6%, 285 parts of an alkylene polyamine having an average composition corresponding stoichiometrically to tetraethylene pentamine and 1200 parts of benzene is heated to reflux. The temperature of the mixture is then slowly increased over a o

4-hour period to 170 C while benzene is removed. The cooled mixture is diluted with an equal volume of mixed hexanes and absolute ethanol (1:1). The mixture is heated to reflux and 1/3 volume of 10% aqueous sodium carbonate is added to the mixture. After stirring, the mixture is allowed to cool and phase separate. The organic phase is washed with water and stripped to provide the desired polyisobutenyl polyamine having a nitrogen content of 4.5% by weight. Example B-2

A mixture of 140 parts of toluene and 400 parts of a polyisobutenyl succinic anhydride (prepared from the poly(isobutene) having a molecular weight of about 850, vapor phase osmometry) having a saponification number 109, and 63.6 parts of an ethylene amine mixture having an average composi¬ tion corresponding in stoichiometry to tetraethylene pentamine, is heated to 150°C while the water/toluene azeotrope is removed. The reaction mixture is then heated to 150°C under reduced pressure until toluene ceases to distill. The residual acylated polyamine has a nitrogen content of 4.7% by weight. Example B-3

To 1,133 parts of commercial diethylene triamine heated at 110-150°C is slowly added 6820 parts of isostearic acid over a period of two hours. The mixture is held at 150°C for one hour and then heated to 180°C over an additional hour. Finally, the mixture is heated to 205°C over 0.5 hour; throughout this heating, the mixture is blown with nitrogen to remove volatiles. The mixture is held at 205-230^βC for a total of 11.5 hours and the stripped at 230°C/20 torr (2.65KPa) to provide the desired acylated polyamine as residue containing 6.2% nitrogen by weight. Example B-4

To a mixture of 50 parts of a polypropylene-substituted phenol (having a molecular weight of about 900, vapor phase osmometry) , 500 parts of mineral oil (a solvent refined paraffinic oil having a viscosity of 100 SUS at 100^βF) and 130 parts of 9.5% aqueous dimethyla ine solution (equivalent to 12 parts amine) is added dropwise, over an hour, 22 parts of a 37% aqueous solution of formaldehyde, (corresponding to 8 parts aldehyde) . During the addition, the reaction tempera¬ ture is slowly increased to 100°C and held at that point for three hours while the mixture is blown with nitrogen. To the cooled reaction mixture is added 100 parts toluene and 50 parts mixed butyl alcohols. The organic phase is washed three times with water until neutral to litmus paper and the organic phase filtered and stripped to 200°C/5-10 (0.66- 1.33KPa) torr. The residue is an oil solution of the final product containing 0.45% nitrogen by weight. Example B-5

A mixture of 140 parts of a mineral oil, 174 parts of a poly(isobutene)-substituted succinic anhydride (molecular weight 1000) having a saponification number of 105 and 23 parts of isostearic acid is prepared at 90°C. To this mixture there is added 17.6 parts of a mixture of poly¬ alkylene amines having an overall composition corresponding to that of tetraethylene pentamine at 80°-100°C throughout a period of 1.3 hours. The reaction is exothermic. The mixture is blown at 225°C with nitrogen at a rate of 5 pounds (2.27 Kg) per hour for 3 hours whereupon 47 parts of an aqueous distillate is obtained. The mixture is dried at 225°C for 1 hour, cooled to 100°C and filtered to provide the desired final product in oil solution. Example B-6

A substantially hydrocarbon-substituted succinic anhydride is prepared by chlorinating a polyisobutene having a molecular weight of 1000 to a chlorine content of 4.5% and then heating the chlorinated polyisobutene with 1.2 molar proportions of maleic anhydride at a temperature of 150° -220°C. The succinic anhydride thus obtained has an acid number of 130. A mixture of 874 grams (1 mole) of the succinic anhydride and 104 grams (1 mole) of neopentyl glycol is mixed at 240°-250°C/30 mm (4 KPa) for 12 hours. The residue is a mixture of the esters resulting from the esterification of one and both hydroxy radicals of the glycol. It has a saponification number of 101 and an alco¬ holic hydroxyl content of 0.2% by weight. Example B-7

The dimethyl ester of the substantially hydrocarbon- substituted succinic anhydride of Example B-2 is prepared by heating a mixture of 2185 grams of the anhydride, 480 grams of methanol, and 1000 cc. of toluene at 50°-65°C while hydrogen chloride is bubbled through the reaction mixture for 3 hours. The mixture is then heated at 60°-65°C for 2 hours, dissolved in benzene, washed with water, dried and filtered. The filtrate is heated at 150°C/60 mm (8 KPa) to rid it of volatile components. The residue is the defined dimethyl ester. Example B-8

A carboxylic acid ester is prepared by slowly adding 3240 parts of a high molecular weight carboxylic acid (pre¬ pared by reacting chlorinated polyisobutylene and acrylic acid in a 1:1 equivalent ratio and having an average molecu¬ lar weight of 982) to a mixture of 200 parts of sorbitol and 100 parts of diluent oil over a 1.5-hour period while main¬ taining a temperature of 115°-125°C. Then 400 parts of additional diluent oil are added and the mixture is main¬ tained at about 195°-205°C for 16 hours while blowing the mixture with nitrogen. An additional 755 parts of oil are then added, the mixture cooled to 140°C, and filtered. The filtrate is an oil solution of the desired ester. Example B-9

An ester is prepared by heating 658 parts of a carboxylic acid having an average molecular weight of 1018 (prepared by reacting chlorinated polyisobutene with acrylic acid) with 22 parts of pentaerythritol while maintaining a temperature of about 180°-205°C for about 18 hours during which time nitrogen is blown through the mixture. The mixture is then filtered and the filtrate is the desired ester. Example B-10

To a mixture comprising 408 parts of pentaerythritol and 1100 parts oil heated to 120°C, there is slowly added 2946 parts of the acid of Example B-9 which has been preheated to 120°C, 225 parts of xylene, and 95 parts of diethylene glycol dimethylether. The resulting mixture is heated at 195°- 205°C, under a nitrogen atmosphere and reflux conditions for eleven hours, stripped to 140"C at 22 mm (2.92 KPa) (Hg) pressure, and filtered. The filtrate comprises the desired ester. It is diluted to a total oil content of 40%. Example B-ll

To a mixture of 400 parts of polyisobutene-substituted phenol (wherein the polyisobutene substituent contains approximately 100 carbon atoms) , 125 parts of textile spirits and 266 parts of a diluent mineral oil at 28°C is slowly added 22.83 parts of nitric acid (70%) in 50 parts of water over a period of 0.33 hours. The mixture is stirred at 28-34°C for 2 hours and stripped to 158^β/4 KPa (30 torr.), filtration provides an oil solution (40%) of the desired intermediate having a nitrogen content of 0.88%. Example B-12

A mixture of 93 parts of the product solution of Example C-17 and 93 parts of a mixture of toluene and isopropanol (50/50 by weight) is charged to an appropriately sized hydrogenation vessel. The mixture is degassed and nitrogen purged; 0.31 part of a commercial platinum oxide catalyst (86.4% PtO_) is added. The reaction vessel is pressured to 392 KPa (57 psig) and held at 50-60° for 21 hours. A total of 0.6 mole of hydrogen is fed to the reaction vessel. The reaction mixture is filtered and the filtrate stripped to yield the product containing 0.44% nitrogen in oil. THE HYDROCARBON-SOLUBLE POLYCARBOXYLIC ACID Component (C) is employed to minimize or prevent gela¬ tion when the hydrocarbon-soluble alkali or alkaline earth metal containing composition is in the presence of a two- cycle oil. It is believed that certain components within the two-cycle oils which will be described later are responsible for the gelation. Thus the hydrocarbon-soluble polycarboxyl¬ ic acid fix is used for the gelation problem. Examples of hydrocarbon-soluble polycarboxylic acids follow.

Aromatic carboxylic acids are represented by the general formula:

(R*)_aAr*(CXXH)_m Formula XVI where R* is an aliphatic hydrocarbon-based group of at least 30 carbon atoms, and no more than about 400 aliphatic carbon atoms (preferably no more than 150 carbon atoms) , a is an integer of from one to three, Ar* is a polyvalent aromatic hydrocarbon nucleus of up to about 14 carbon atoms, each X is independently a sulfur or oxygen atom, and m is an integer of from two to four with the proviso that R* and a are such that there is an average of at least 50 aliphatic carbon atoms provided by the R* groups for each acid molecule represented by Formula XVI. Examples of aromatic nuclei represented by the variable Ar* are the polyvalent aromatic radicals derived from benzene, naphthalene, anthracene, phenanthrene, indene, fluorene, biphenyl, and the like. Generally, the radical represented by Ar* will be a polyvalent nucleus derived from benzene or naphthalene such as phenylenes and naphthylene, e.g., methyl-phenylenes, ethoxyphenylenes, nitrophenylenes, isopropylphenylenes, hydroxyphenylenes, mercaptophenylenes, phenylenes, N,N-diethylaminophenylenes, chlorophenylenes, dipropoxynaphthylenes, triethylnaphthylenes, and similar tri-, tetra-, pentavalent nuclei thereof, etc.

The R* groups are usually purely hydrocarbyl groups, preferably groups such as alkyl or alkenyl radicals. How¬ ever, the R* groups can contain small number substituents such as phenyl, cycloalkyl (e.g., cyclohexyl, cyclopentyl, etc.) and nonhydrocarbon groups such as nitro, amino, halo (e.g., chloro, bromo, etc.) lower alkoxy, lower alkyl mer¬ capto, oxo substituents (i.e.,=0), thio groups (i.e.,=S), interrupting groups such as -NH-, -0-, -S-, and the like provided the essentially hydrocarbon character of the R* group is retained. The hydrocarbon character is retained for purposes of this invention so long as any non-carbon atoms present in the R* group do not account for more than about 10% of the total weight of the R* groups.

Examples of some R* groups include polybutenyl, poly- propyl groups, and materials derived from polymerized olefins such as polychloroprenes, polyethylenes, polypropylenes, polyisobutylenes, ethylenepropylene copolymers, chlorinated olefin polymers, oxidized ethylenepropylene copolymers, and the like. Likewise, the group Ar may contain non-hydrocarbon substituents, for example, such diverse substituents as lower alkoxy, lower alkyl mercapto, nitro, halo, alkyl or alkenyl groups of less than four carbon atoms, hydroxy, mercapto and the like.

A preferred type of carboxylic acid used in this inven¬ tion are those derived from alkenyl succinates of the general formula:

R*CH(COOH)CH₂COOH Formula XVII . wherein R* is as defined above in Formula XVI. Such acids and means for making them are set forth in U.S. Patents 3,271,130; 3,567,637 and 3,632,610. Example C-l

To a mixture of 500 grams (0.92 equivalent) of a poly¬ isobutenyl succinic anhydride (having an acid number of 103 and prepared from maleic anhydride and chlorinated polyiso¬ butylene having an average chlorine content of 4.3 weight percent and an average of 70.7 carbon atoms) , and 300 grams of mineral oil, there is added, at 80°C, 50 grams of water. The mixture is agitated for 1 hour at 80°C with nitrogen purge for one and one-half hours. Example C-2

To a mixture of 1,094 grams (2 equivalents) of a poly¬ isobutenyl succinic anhydride (having an acid number of 102 and prepared, as in Example C-1, from maleic anhydride and chlorinated polyisobutylene having an average chlorine content of 4.3 weight percent and an average of 71.4 carbon atoms) , 762 grams of mineral oil, and 160 grams of water. The product is then heated 90°C and blown with nitrogen for one hour. It is desired that the product contain less than 1% by weight water, preferably less than 0.5% and most preferably less than 0.3% water.

THE LIQUID HYDROCARBON FUEL

The fuel component useful in the present invention is obtained as a hydrocarbon distillate. Gasolines are supplied in a number of different grades depending on the type of service for which they are intended. The gasolines utilized herein include those designed for motor and aviation gaso¬ lines. Motor gasolines include those defined by ASTM speci¬ fication D-439-86 and are composed of a mixture of various hydrocarbons including aromatics, olefins, paraffins, isoparaffins, naphthenes and occasionally diolefins. Motor gasolines utilize a majority of components normally have a boiling range within the limits of about 20°C to 230°C while aviation gasolines have narrower boiling ranges, usually within the limits of about 37°C to 165°C.

The gasoline may have any of the typically added ingre¬ dients provided that there are no adverse effects to obtain¬ ing the performance for the valve seat recession and the avoidance of gelation.

One such ingredient which is typically included in gasoline is lead in the form of a compound such as tetraethyl lead or tetramethyl lead. It is first noted that lead is being regulated out of gasoline in many countries. Those countries still allowing some amounts of lead in the gasoline allow "low-lead" formulation. Typically, a low-lead gasoline contains less than about 0.5 gram of lead per gallon of fuel. This invention is concerned in one aspect with low-lead fuels containing as little as 0.1 gram of lead per gallon (0.0264 g/liter) of gasoline.

It is further preferred in the present invention that the gasoline be lead-free. By lead-free it is meant that small trace amounts of lead, significantly less than the amounts in a low-lead fuel, are tolerated. That is, no-lead or lead-free gasoline compositions occasionally contain trace amounts of lead due to contamination by leaded fuels. Thus, the term no-lead or lead-free gasolines includes very small amount of lead; however, it is preferred that the end gaso¬ line product be completely lead-free.

THE OIL OF LUBRICATING VISCOSITY

The oil of lubricating viscosity which is utilized in the preparation of the lubricants of the invention may be based on natural oils, synthetic oils, or mixtures thereof. Natural oils include animal oils and vegetable oils (e.g., castor oil, lard oil) as well as mineral lubricating oils such as liquid petroleum oils and solvent-treated or acid- treated mineral lubricating oils of the paraffinic, naphthenic or mixed paraffinic-naphthenic types. Oils of lubricating viscosity derived from coal or shale are also useful. Synthetic lubricating oils include hydrocarbon oils and halosubstituted hydro-carbon oils such as polymerized and interpolymerized olefins (e.g., polybutylenes, polypropyl- enes, propylene-isobutylene copolymers, chlorinated poly¬ butylenes, etc.); poly(l-hexenes) , poly(l-octenes) , poly- (1-decenes) , etc. and mixtures thereof; alkylbenzenes (e.g., dodecyl-benzenes, tetradecylbenzenes, dinonylbenzenes, di-(2-ethylhexyl)-benzenes, etc.); polyphenyls (e.g., bi- phenyls, terphenyls, alkylated polyphenyls, etc.); alkylated diphenyl ethers and alkylated diphenyl sulfides and the derivatives, analogs and homologs thereof and the like.

Alkylene oxide polymers and interpolymers and deriva¬ tives thereof where the terminal hydroxyl groups have been modified by esterification, etherification, etc. , constitute another class of known synthetic lubricating oils that can be used. These are exemplified by the oils prepared through polymerization of ethylene oxide or propylene oxide, the alkyl and aryl ethers of these polyoxyalkylene polymers (e.g., methylpolyisopropylene glycol ether having an average molecular weight of about 1000, diphenyl ether of polyethyl¬ ene glycol having a molecular weight of about 500-1000, diethyl ether of polypropylene glycol having a molecular weight of about 1000-1500, etc.) or mono- and polycarboxylic esters thereof, for example, the acetic acid esters, mixed C--C₈ fatty acid esters, or the C._ oxo acid diester of tetraethylene glycol.

Another suitable class of synthetic lubricating oils that can be used comprises the esters of dicarboxylic acids (e.g., phthalic acid, succinic acid, alkyl succinic acids, alkenyl succinic acids, maleic acid, azelaic acid, suberic acid, sebacic acid, fumaric acid, adipic acid, linoleic acid dimer, malonic acid, alkyl malonic acids, alkenyl malonic acids, etc.) with a variety of alcohols (e.g., butyl alcohol, hexyl alcohol, dodecyl alcohol, 2-ethylhexyl alcohol, ethylene glycol, diethylene glycol monoether, propylene glycol, etc.) specific examples of these esters include dibutyl adipate, di(2-ethylhexyl) sebacate, di-n-hexyl fumarate, dioctyl sebacate, diisooctyl azelate, diisodecyl azelate, dioctyl phthalate, didecyl phthalate, dieicosyl sebacate, the 2-ethylhexyl diester of linoleic acid dimer, the complex ester formed by reacting one mole of sebacic acid with two moles of tetraethylene glycol and two moles of 2-ethylhexanoic acid and the like.

Esters useful as synthetic oils also include those made from C₅ to C_._ monocarboxylic acids and polyols and polyol ethers such as neopentyl glycol, trimethylol propane, pentaerythritol, dipentaerythritol, tripentaerythritol, etc.

Silicon-based oils such as the polyalkyl-, polyaryl-, polyalkoxy-, or polyaryloxy-siloxane oils and silicate oils comprise another useful class of synthetic lubricants (e.g., tetraethyl silicate, tetraisopropyl silicate, tetra-(2- ethylhexyl)silicate, tetra-(4-methyl-hexyl)sil-icate, tetra- (p-tert-butyl-phenyl)silicate, hexyl-(4-methyl-2-pentoxy)- disiloxane, poly(methyl)siloxans, poly(methylphenyl)silox- anes, etc.). Other synthetic lubricating oils include liquid esters of phosphorus-containing acids (e.g., tricresyl phosphate, trioxtyl phosphate, diethyl ester of decane phosphonic acid, etc.), polymeric tetrahydrofurans and the like.

Unrefined, refined and rerefined oils, either natural or synthetic (as well as mixtures of two or more of any of these) of the type disclosed hereinabove can be used in the concentrates of the present invention. Unrefined oils are those obtained directly from a natural or synthetic source without further purification treatment. For example, a shale oil obtained directly from retorting operations, a petroleum oil obtained directly from primary distillation or ester oil obtained directly from an esterification process and used without further treatment would be an unrefined oil.

Refined oils are similar to the unrefined oils except they have been further treated in one or more purification steps to improve one or more properties. Many such purifica¬ tion techniques are known to those skilled in the art such as solvent extraction, secondary distillation, hydrotreating, hydrocracking, acid or base extraction, filtration, percola¬ tion, etc.

Rerefined oils are obtained by processes similar to those used to obtain refined oils which have been already used in service. Such rerefined oils are also known as reclaimed or reprocessed oils and often are additionally processed by techniques directed to removal of spent addi¬ tives and oil breakdown products.

ADDITIONAL INGREDIENTS

A two-cycle fuel mixture often contains additional additives known to those skilled in the art. These ingredi¬ ents include dyes, octane improvers, anti-oxidants such as 2,6-di-tertiary-butyl-4-methylphenol, rust inhibitors, bacteriostatic agents, gum inhibitors, metal deactivators, demulsifiers, upper cylinder lubricants, anti-icing agents and the like.

In particular phenolic components are useful in two-cy¬ cle fuels. The phenolic components are useful in eliminating or reducing engine varnish deposits and in protecting against piston ring seal failure. Such components are described in United States Patent 4,740,321 issued April 26, 1988 to Davis et al which is herein specifically incorporated by reference.

In particular phenolic compounds of the formula (R) AR(OH)_b or salts thereof wherein R is a substantially saturated, hydrocarbon based group having at least 10 aliphatic carbon atoms; a and b are each independently an integer of 1 up to about 3 times the number of aromatic nuclei present in Ar with the proviso that the sum of a and b does not exceed the unsatisfied valences of Ar; and Ar is a linked polynuclear moiety wherein the bridging linkages are sulfur-containing moieties, having 0 to 3 optional substituents consisting of lower alkyl, lower alkoxy, methylol or lower hydrocarbon-substituted methylol, halo and combinations of 2 or more of the said optional substituents.

A further description of the phenolic materials useful herein are such that all of the Ar moities are unsubstituted except for the R and OH groups (and any bridging groups) .

For such reasons as cost, availability, performance etc., the Ar moiety is normally a benzene nucleus, sulfur bridged benzene nucleus, or a naphthalene nucleus. Thus, a typical Ar moiety is a sulfurized benzene or naphthalene nucleus having 3 to 5 unsatisfied valences, so that one or two of said valences may be satisfied by a hydroxyl group with the remaining unsatisfied valences being, insofar as possible, either ortho or para to a hydroxyl group. Pre¬ ferably, Ar is a sulfurized benzene nucleus^* having 3 to 4 unsatisfied valences so that one can be satisfied by a hydroxyl group with the remaining 2 or 3 being either ortho or para to the hydroxyl group.

The phenolic compounds used in the two-cycle oils of the present invention contain, directly bonded to the aromatic moiety Ar, a substantially saturated monovalent hydrocarbon based group R of at least about 10 aliphatic carbon atoms. This R group preferably contains 10 and up to about 400 aliphatic carbon atoms. More than one such group can be present, but usually, no more than 2 or 3 such groups are present for each aromatic nucleus in the aromatic moiety Ar. The total number of R groups present is indicated by the value for "a" in the formula. Usually, the hydrocarbon-based group has a least about 10, typically, 10 to 30 aliphatic carbon atoms and up to about 400, more typically, up to about 300 aliphatic carbon atoms.

Illustrative hydrocarbon based groups containing at least ten carbon atoms are n-decyl, n-dodecyl, tetrapro- penyl, n-octadecyl, oleyl, chlorooctadecyl, triicontanyl, etc. Generally, the hydrocarbon-based groups R are made from homo- or interpolymers (e.g. copolymers, terpolymers) or mono- and di-olefins having 2 to 10 carbon atoms, such as ethylene, propylene, butene-1, isobutene, butadiene, isoprene, 1-hexene, 1-octene, etc. Typically, these olefins are 1-monoolefins. The R groups can also be derived from the halogenated (e.g., chlorinated or brominated) analogs of such homo- or interpolymers. The R groups can, however, be made from other sources, such as monomeric high molecular weight alkenes (e.g., 1-tetracontene) and chlorinated analogs and hydrochlorinated analogs thereof, aliphatic petroleum frac¬ tions, particularly paraffin waxes and cracked and chlori¬ nated analogs and hydrochlorinated analogs thereof, white oils, synthetic alkenes such as those produced by the Zieg- ler-Natta process (e.g., poly(ethylene)greases) and other sources known to those skilled in the art. Any unsaturation in the R groups may be reduced or eliminated by hydrogenation according to procedures known in the art.

As used herein, the term "hydrocarbon-based" denotes a group having a carbon atom directly attached to the remainder of the molecule and having a predominately hydrocarbon character within the context of this invention. Therefore, hydrocarbon-based groups can contain up to one non-hydrocar¬ bon radical for every ten carbon atoms provided this non-hy¬ drocarbon radical does not significantly alter the predomi¬ nantly hydrocarbon character of the group. Those skilled in the art will be aware of such radicals, which include, for example, hydroxyl, halo (especially chloro and fluoro) , alkoxyl, alkyl mercapto. alkyl sulfoxy, etc. Usually, however, the hydrocarbon-based groups R are purely hydro¬ carbyl and contain no such non-hydrocabyl radicals.

The hydrocarbon-based groups R are substantially satu¬ rated, that is, they contain no more than one carbon-to-car¬ bon unsaturated bond for every ten carbon-to-carbon single bonds present. Usually, they contain no more than one carbon-to-carbon non-aromatic unsaturated bond for every 50 carbon-to-carbon bonds present.

The hydrocarbon-based groups of the phenols used in the two-cycle oils of this invention are also substantially aliphatic in nature, that is, they contain no more than one non-aliphatic moiety (cycloalkyl, cycloalkenyl or aromatic) group of six or less carbon atoms for every ten carbon atoms in the R group. Usually, however, the R groups contain no more than one such non-aliphatic group for every fifty carbon atoms, and in many cases, they contain no such non-aliphatic groups at all; that is, the typical R groups are purely aliphatic. Typically, these purely aliphatic R groups are alkyl or alkenyl groups.

Further phenols which may be used herein include the described in Canadian Patent 1,096,886 issued to Lange on March 3, 1981. The a inophenols of Lange are similar to those of Davis, however, the aromatic groups are directly linked to one another. The Lange patent is herein incor¬ porated by reference.

Specific examples of the substantially saturated hydro¬ carbon-based R groups containing an average of more than 30 carbon atoms are the following: a mixture of poly(ethylene/propylene) groups of about 35 to about 70 carbon atoms, a mixture of the oxidatively or mechanically degraded poly(ethylene/propylene) groups of about 35 to about 70 carbon atoms, a mixture of poly(propylene/1-hexene) groups of about 80 to about 150 carbon atoms, and a mixture of poly(isobutene) groups having an average of 50 to 75 carbon atoms

A preferred source of the group R are poly(isobutene)s obtained by polymerization of a C. refinery stream as previ¬ ously described.

The attachment of the hydrocarbon-based group R to the aromatic moiety Ar of the phenols used in the two-cycle oils of this invention can be accomplished by a number of tech¬ niques well known to those skilled in the art. One particu¬ larly suitable technique is the Friedel-Crafts reaction, wherein an olefin (e.g., a polymer containing an olefinic bond) , or halogenated or hydrohalogenated analog thereof, is reacted with a phenol. the reaction occurs in the presence of a Lewis acid catalyst (e.g., boron trifluoride and its complexes with ethers, phenols, hydrogen fluoride, etc., aluminum chloride, aluminum bromide, zinc dichloride, etc.). Methods and conditions for carrying out such reactions are well known to those skilled in the art. See, for example, the discussion in the article entitled, "Alkylation of Phenols" in Kirk-Othmer Encyclopedia of Chemical Technology", Second Edition, Vol. 1, pages 894-895, Interscience Publish¬ ers, a division of John Wiley and Company, N.Y., 1963. Other equally well known appropriate and convenient techniques for attaching the hydrocarbon-based group R to the aromatic moiety Ar will occur readily to those skilled in the art.

The phenols often used in the two-cycle oils of this invention contain at least one of each of the following substituents: a hydroxyl group and a R group as defined above. Each of the foregoing groups must be attached to a carbon atom which is a part of an aromatic nucleus in the Ar moiety. They need not, however, each be attached to the same aromatic ring if more than one aromatic nucleus is present in the Ar moiety.

Examples of such aromatic compounds include: Example D-l

An alkylated phenol is prepared by reacting phenol with polyisobutene having a number average molecular weight of approximately 1000 (vapor phase osmometry) in the presence of a boron trifluoride phenol complex catalyst. Stripping of the product thus formed first to 230°C/760 torr (lOlKPa- vapor temperature) and then to 205°C vapor temperature/50 torr (6.65KPa) provides purified alkylated phenol. Example D-2

The procedure of Example D-l is repeated except that the polyisobutene has an average number molecular weight of about 1400. Example D-3

Polyisobutenyl chloride (4885 parts) having a viscosity at 99°C of 1306 SUS and containing 4.7% chlorine is added to a mixture of 1700 parts phenol, 118 parts of a sulfuric acid-treated clay and 141 parts zinc chloride at 110°-155°C during a 4-hour period. The mixture is then kept at 155° -185°C for 3 hours before being filtered through diatomaceous earth. The filtrate is vacuum stripped to 165°C/0.5 torr (0.065 KPa). The residue is again filtered through diatomaceous earth. The filtrate is a substituted phenol having an OH content of 1.88%. Example D-4

Aluminum chloride (76 parts) is slowly added to a mixture of 4220 parts of polyisobutenyl chloride having a number average molecular weight, Mn, of iOOO (VPO) and containing 4.2% chlorine, 1516 parts phenol, and 2500 parts toluene at 60°C. The reaction mixture is kept at 95°C under a below-the-surface nitrogen gas purge for 1.5 hours. Hydrochloric acid (50 parts of a 37.5% aqueous hydrochloric acid solution) is added at room temperature and the mixture stored for 1.5 hours. The mixture is washed five times with a total of 2500 parts water and then vacuum stripped to 215°C/1 torr (0.13 KPa). The residue is filtered at 150°C through diatomaceous earth to improve its clarity. The filtrate is a substituted phenol having an OH content of 1.39%, a Cl content of 0.46% and a Mn of 898 (VPO) .

Other examples of alkylated phenols useful in accordance with this invention are shown in Table A.

TABLE A

Example Name Mol. Wt.

D-5 2,2'-dipoly(isobutene)y1-4,4'- 2500 dihydroxybiphenyl

D-6 8-hydroxy-poly(propene)yl- 900

1-azanaphthalene

D-7 4-poly(isobutene)yl-1-naphthol 1700

D-8 2-poly(propene/butene-l)yl- _ 3200

4,4 '-isopropylidene-bisphenol D-9 4-tetra(propene)yl-2-hydroxy- anthracene

D-10 4-oσtadecyl-l,3-dihydroxybenzene -

D-ll 4-poly(isobutene)-3-hydroxy- 1300 pyridine

1 Number average molecular weight by vapor phase osmometry.

2 The molar ratio of propene to butene-1 in the substituent is 2:3.

Example D-l 2

While maintaining a temperature of 55° 1000 parts phenol and 68 parts sulfonated polystyrene catalyst (marketed as Amberlyst-15 by Rohm and Haas Company) are charged to a reactor equipped with a stirrer, condenser, thermometer and subsurface gas inlet tube. The reactor contents are then heated to 120° while nitrogen blowing for 2 hours. 1232 parts propylene tetramer is charged, and the reaction mixture is stirred at 120° for 4 hours. Agitation is stopped, and the batch is allowed to settle for 0.5 hour. The crude super¬ natant reaction mixture is filtered and vacuum stripped until a miximum of 0.5 percent residual propylene tetramer remains.

Examples of sulfurized alkylated phenols are: Example D-13

A reactor equipped with a stirrer, condenser, ther¬ mometer and subsurface addition tube is charged with 1000 parts of the reaction product of Example D-12. The tempera¬ ture is adjusted to 48-49° and 319 parts sulfur dichloride is added while the temperature is kept below 60°. The batch is then heated to 88-93° while nitrogen blowing until the acid number (using bromphenol blue indicator) is less than 4.0. 400 parts diluent oil is then added, and the mixture is mixed thoroughly. Example D-l4

Following the procedure of Example D-13, 1000 parts of the reaction product of Example D-12 is reacted with 175 parts of sulfur dichloride. The reaction product is diluted with 400 parts diluent oil. Example D-15

Following the procedure of Example D-13, 1000 parts of the reaction product of Example D-12 is reacted with 319 parts of sulfur dichloride. 788 parts diluent oil is added to the reaction product, and the materials are mixed thor¬ oughly. Example D-l6

A basic calcium salt of a phenol sulfide is prepared by reacting the sulfurized phenol of Example D-14 with calcium hydroxide in the presence of acetic acid, methanol and polyisobutenylsuccinic anhydride and blowing with CO_.

A further component useful in a two-cycle fuel is a polyamide ashless detergent (E) particularly one having pour point depressing properties. Typically the polyamide compo¬ nent will be of a fatty acid and a polyalkylene polyamine in which the fatty acids are from about 5 to about 30 mole percent of straight-chain fatty acids and about 70 to about 95 mole percent of branched-chain fatty acids. Typically the fatty acids used in the polyamide contain from about 12 to about 30 carbon atoms each and the polyalkylene polyamines contain from 2 to 6 alkylene units each with from 2 to 4 carbon atoms in each alkylene group. The polyamides typical¬ ly contain from 1 to 3 amine groups in addition to the amide groups.

The polyamides utilized herein may be illustrated by the formula

H₂N[R₁N(R₂)]_nR₁NH₂ in which the alkylene group R. contains from 2 to 4 carbon atoms, the radical R_ is hydrogen or an acyl group R C(=0)- which is derived from a mixture of about 5 to about 30 mole percent of straight-chain fatty acid and about 70 to about 95 mole percent of branched-chain fatty acids containing about 12 to about 30 carbon atoms and n is an integer 1 to 5. The acyl group R_ is an aliphatic hydrocarbon residue of fatty acids and therefore contains about 11 to about 29 carbon atoms, there being more then 1 of the acyl^' groups in the structural formula for the polyamides described herein.

The polyamide is conveniently prepared according to known methods by reacting the polyamine and the mixed fatty acids at conventional temperatures for the usual period of time required to amidify the amino groups of the polyalkylene polyamine. For present purposes temperatures in the range from about 121°C (250°F) to about 260°C (500°F) are suitable. Usually the amidification reaction requires from about 2 to 10 hours. Means for removing water of condensation is employed and reduced pressures are desirable to effect amidification at the lower reaction temperatures.

The proportions of fatty acid mixture and polyalkylene polyamine may be such that the moles of the fatty acids are equal to the molar equivalents of amine groups in the poly¬ alkylene polyamine. As already mentioned it is preferred that moles of fatty acid be on the average of from about 1 to about 3 moles less than the number of available amino groups in the polyamine.

Suitable fatty acids for the preparation of the poly¬ amides of the present invention contain from 12 to 30 carbon atoms as mentioned above and preferably from 16 to 20 carbon atoms. Illustrative straight-chain acids include behenic acid, tridecanoic acid, lauric acid, myristic acid, palmitic acid, stearic acid, eiconsanoic acid, triacontanoic acid, etc.

Suitable branched-chain fatty acids are those derived by synthesis such as oxidation of olefins and polyolefins. Acids derived from the Oxo process (oxidation of Oxo aldehyde intermediates from propylene tetramer) are also suitable. Another source is the polymerization of unsaturated acids followed by hydrogenation. For example, an unsaturated acid such as linoleic acid is dimerized in accordance with typical polymerization techniques. During the reaction part of the acid product is broken down to give an unsaturated mono acid by-product having methyl chain branching. This product is hydrogenated resulting in a branched-chain saturated fatty acid of 18 carbon atoms.

For present purposes it has been found that Emery Acid 3101 R is particularly useful. This is a monocarboxylic acid having an equivalent weight of 310. It is described as a saturated 18 carbon atom fatty acid having methyl chain branching.

The polyalkylene polyamines of the invention as men¬ tioned above contain from 2 to 6 alkylene amine units with from 2 to 4 carbon atoms in each alkylene group. Illus¬ trative amines include diethylenetriamine, triethylene- tetraamine, tetraethylenepentaamine, hexaethylenehepta-amine, heptaethyleneoctaamine, tetrapropylenepentaamine, hexabutyl- eneheptaamine and the like. For present purposes triethyl- enetetraamine and tetraethylpentaamine are preferred for availability and effectiveness of the polyamides prepared from them.

The following examples are illustrative of typical methods for preparing the polyamide and of lubricant composi¬ tions containing the polyamide.

Example I-E

In this example the polyamide of tetraethylenepenta¬ amme and a 10:90 mixture of straight and branched-chain acids is prepared.

A reaction vessel is charged with a mixture of 3.7 parts by weight of tetraethylenepentaamme and 0.0002 part by weight of silicone foam inhibitor. The mixture is blanketed with nitrogen gas and heated to about 121°C (250°F) . A mixture of monocarboxylic acids amounting to about 18.2 parts by weight is introduced to the reaction vessel. This mixture consists of 10 mole percent stearic acid and 90 mole percent Emery 3101 R acid. The mole ratio of tetraethylenepentaamine to total acid is about 1 to 3. The reaction mixture is heated to about 149°C (300°F) for a period of about l hour and water of reaction is removed. Following this the reac¬ tion temperature is raised to about 204°C (400°F) at atmo¬ spheric pressure for about one hour and then maintained at about 193°C (380°F) under a vacuum equivalent of 0.53 KPa (4 mm) of mercury pressure for a period of about 7 hours. Example II-E

This example illustrates the preparation of the polyamide of tetraethylenepentaamine and a 5:95 mixture of straight and branched-chain acids.

To a 2 liter, 3 neck flask equipped with stirrer, thermometer, reflux condenser and means of heating there is charged 189 g. of tetraethylenepentaamine (1.0 mole) and 0.01 g. of silicon foam inhibitor. The charge is heated under nitrogen to about 88°C (190°F) . A mixture of 42 g. stearic acid (0.15 mole) and 873 g. Emery 3101 R acid (2.85 mole) is then added. The contents of the flask are heated to 193°C (380°F) and then put under a vacuum equivalent to about 2.65 KPa (20 mm) of mercury pressure. The reaction mixture is held under these conditions for about six hours and then cooled. The yield of product is quantitative. Example III-E

In this example the polyamide of tetraethylenepenta¬ amine and a 20:80 mixture of straight and branched-chain acids is prepared.

In accordance with the procedure outlined in Example II-E above, 189 g. of tetraethylenepentaamine, 168 g. of stearic acid (20 mole percent of total acid) and 744 g. of Emery 3101 R acid (80 mole percent of total acid) are react¬ ed. A total of 3.0 moles of acid per mole of tetraethyl¬ enepentaamine is used. The yield of the product amounts to about 100% on the basis of the reactants.

Other materials which are often added to two-cycle oils or fuels include short chain fatty acids such as isostearic acid. These materials are used for rust control but when in the presence of a material such as component (A) may gel blocking fuel filters. Another source of such materials is from saponification of the amides described above. The fatty acids are present or can become available in the oil at 0.001% to 1% by weight of the lubricating oil. Free sulfonic acids such as those obtained in Examples A-l to A-5 may be used as a supplemental anti-gelling agent.

PROPORTION OF INGREDIENTS

The amount of component (A) , the alkali metal or alka¬ line earth metal containing composition included in the fuel compositions is an amount sufficient to reduce valve seat recession when the fuels are utilized in an internal combus¬ tion engine. Generally, the fuel will contain less than about 0.5 gram preferably less than 0.3 gram of the alkali or alkaline earth metal compound per liter of fuel. The fuel composition will typically contain about 1 to about 100 parts of the alkali or alkaline earth metal per million parts of the fuel although amounts of 4 to about 60 parts per million appear to be adequate for most applications.

The amount of the hydrocarbon-soluble ashless dispersant utilized in the fuel composition will vary over a wide range. Typically, the metal-containing composition (A) to the ashless dispersant (B) ranges from about 4:0.1 to about 1:4. The amount of ashless dispersant included in the particular fuel composition can be determined readily by one skilled in the art. Generally the two-cycle fuel will be prepared to contain about 5 to about 500 parts, and more preferably about 10 to 400 parts by weight of the ashless dispersant (B) per million parts by weight of fuel.

Component (C) , the polycarboxylic acid, is typically employed in a weight ratio to component (A) at about 5:1 to about 1:5, preferably about 5:2 to about 1:4. The amount of the polycarboxylic acid to the dispersant (B) is typically at about 50:1 to about 1:1, preferably about 20:1 to about 4:1. Component (C) when added to the gasoline is typically at 50 to 1000, preferably 80 to 500 parts per million.

When the oil of lubricating viscosity and the gasoline are combined for combustion the oil of lubricating viscosity is typically used at 1 part to about 15 to about 250 parts of the gasoline, typically about 1 part of the oil of lubricat¬ ing viscosity to about 50 to about 100 parts of the gasoline.

Component (D) the alkylated phenol is typically present in an oil of lubricating viscosity at 0.1% to 15%. Component (E) the source of a fatty acid is typically used at 0.5% to 20% by weight of the oil composition.

PREPARATION OF THE COMPOSITIONS

The oils of lubricating viscosity as described herein are typically formulated as are ordinary oils and contain all manner of components typically found in lubricating oils. The components to be mixed with the oil of lubricating viscosity are typically added to oil in a suitable reaction vessel and physically mixed into the oil at any convenient temperature up to but not including the decomposition temper¬ ature of the lower decomposing component.

The components which are added to the gasoline of the present invention are typically mixed in to the gasoline in a suitable reaction vessel at such temperatures at which the end fuel and/or the individual components are nonreactive or nondecomposing. Occasionally, it is desirable to predissolve a lesser soluble component into a light oil which is then more easily mixed into the gasoline.

The following are suggested exemplifications of the compositions of the present invention. EXAMPLE I An outboard motor formulation is prepared. A bright stock oil is present at about 15%. Stoddard solvent is utilized at 15% with 9% of the reaction product of tetraeth¬ ylene pentamine and isostearic acid. An aminophenol corres¬ ponding to Example B-12 is used at 0.5%. The balance is 350 neutral and 650 neutral oils in a 1:1 weight ratio. The formulation is resistant to gelation upon storage and use.

EXAMPLE II A two-cycle fuel composition is prepared by mixing the oil of Example I at 1 part per 40 parts of unleaded gasoline. To 1000 parts of the foregoing treated fuel is added 0.4 part of the valve protecting additive of Example A-l and 0.2 part of the ashless dispersant of Example B-12, and 0.4 part of the succinic acid derivative of Example C-2. This composi¬ tion has valve protecting properties and is resistant to gelation.

Claims

What is claimed is:

1. A composition for internal combustion engines comprising a major amount of a liquid hydrocarbon fuel and a minor amount of

(A) at least one hydrocarbon-soluble alkali or alkaline earth metal containing composition containing at least 8 aliphatic carbon atoms and

(B) at least one hydrocarbon-soluble ashless dispersant, and

(C) a hydrocarbon-soluble polycarboxylic acid.

2. The composition of claim 1 containing less than 0.5 gram of lead per liter of fuel.

3. The composition of claim 1 wherein (C) is a hydro¬ carbyl substituted succinic acid.

4. The composition of claim 1 wherein (A) is a neutral or basic salt of an organic sulfonic acid.

5. The composition of claim 1 containing from about 1 to 100 parts per million of alkali metal.

6. The composition of claim 1 wherein (A) is a sodium salt.

7. The composition of claim 1 wherein the dispersant (B) is selected from the group consisting of

(i) at least one hydrocarbyl-substituted amine wherein the hydrocarbyl substituent is substantially ali¬ phatic and contains at least 8 carbon atoms;

(ii) at least one acylated, nitrogen-containing compound having a substituent of a least 10 aliphatic carbon atoms made by reacting a carboxylic acid acylating agent with at least one amino compound containing at least one -NH- group, said acylating agent being linked to said amino compound through an imido, amido, amidine, or acyl-oxy ammonium linkage;

(iii) at least one nitrogen-containing condensate of a phenol, aldehyde and amino compound having at least one -NH- group;

(iv) at least one ester of a substituted carboxylic acid ;

(v) at least one polymeric dispersant;

(vi) at least one hydrocarbon substituted phenolic dispersant; and

(vii) at least one fuel soluble alkoxylated deriva¬ tive of an alcohol, phenol, or amine.

8. The composition of claim 1 also containing a free organic sulfonic acid.

9. The composition of claim 1 wherein the hydro¬ carbon-soluble polycarboxylic acid is a hydrocarbyl-substi¬ tuted succinic acid having from 30 to 150 carbon atoms in the hydrocarbyl group.

10. The composition of claim 1 wherein the fuel is unleaded.

11. The composition of claim 1 wherein (A) is the basic salt of the hydrocarbon-soluble alkali or alkaline earth metal-containing composition.

12. A composition suitable for use in an internal combustion engine comprising a major amount of a liquid hydrocarbon fuel and a minor amount sufficient to reduce valve seat recession when the fuel is used in an internal combustion engine of

(A) at least one neutral hydrocarbon soluble alkali metal sulfonate wherein the sulfonate is the alkali metal salt of a sulfonic acid of the formula R (S0_H) or

2 l 2 .

(R )xT(S0j_H)y in w-hich R and R are each independently aliphatic groups, R contains at least about 15 carbon atoms,

2 the sum of the number of carbon atoms in (R ) and T is at least about 15, T is an aromatic hydrocarbon nucleus, and x is a number of 1 to 3, r and y are numbers of 1 to 4 and

(B) at least one hydrocarbon-soluble dispersant which is an aminophenol having a substituent of a least about 30 aliphatic carbon atoms, and

(C) a hydrocarbyl-substituted succinic acid wherein the hydrocarbyl substituent contains from about 30 to 150 carbon atoms.

13. The composition of claim 12 wherein (A) is the sodium salt.

14. A mixture of a major amount of an oil of lubricat¬ ing viscosity containing a minor amount of an oil-soluble polycarboxylic acid having a hydrocarbyl group of 30 or more carbon atoms said mixture being substantially free of water.

15. The composition of claim 14 wherein the oil-soluble carboxylic acid is a hydrocarbyl-substituted succinic acid.

16. The composition of claim 14 wherein the oil of lubricating viscosity is a mineral oil.

17. The composition of claim 14 additionally containing the reaction product of a fatty acid and a polyamine.

18. The composition of claim 14 additionally containing an aminophenol.

19. The composition of claim 17 additionally containing an aminophenol.

20. The composition of claim 14 additionally containing a phenolic compound of the formula (R) AR(OH), or salts thereof wherein R is a substantially saturated, hydrocarbon based group having at least 10 aliphatic carbon atoms; a and b are each independently an integer of 1 up to about 3 times the number of aromatic nuclei present in Ar with the proviso that the sum of a and b does not exceed the unsatisfied valences of Ar; and Ar is a linked polynuclear moiety wherein the bridging linkages are sulfur-containing moieties, having 0 to 3 optional substituents consisting of lower alkyl, lower alkoxy, methylol or lower hydrocarbon-substituted methylol, halo and combinations of 2 or more of the said optional substituents.

21. The composition of claim 17 wherein the reaction product is obtained from a fatty acid and tetraethylene pentamine in which the fatty acids are mixtures of about 5 to about 30 mole percent stearic acid and about 70 to about 95 percent of methyl branched-chained fatty acid produced as a by-product in the dimerization and hydrogenation of linoleic acid, wherein said polyamide contains from 1 to 3 amine groups in addition to the amide groups.

22. The composition of claim 14 additionally containing gasoline.

23. A composition comprising:

(A) at least one hydrocarbon-soluble alkali or alkaline earth metal containing composition containing at least 8 aliphatic carbon atoms and

(B) at least one hydrocarbon-soluble ashless dispersant, and

(C) a hydrocarbon-soluble polycarboxylic acid.

24. The composition of claim 23 wherein (C) is a hydrocarbyl substituted succinic acid.

25. The composition of claim 23 wherein (A) is a neutral or basic salt of an organic sulfonic acid.

26. The composition of claim 23 wherein (A) is a sodium salt.

27. The composition of claim 23 wherein the dispersant .(B) is selected from the group consisting of

(i) at least one hydrocarbyl-substituted amine wherein the hydrocarbyl substituent is substantially aliphatic and contains at least 8 carbon atoms;

(ii) at least one acylated, nitrogen-containing compound having a substituent of at least 10 aliphatic carbon atoms made by reacting a carboxylic acid acylating agent with at least one amino compound containing at least one -NH- group, said acylating agent being linked to said amino compound through an imido, amido, amidine, or acyloxy ammoni¬ um linkage;

(iii) at least one nitrogen-containing condensate of a phenol, aldehyde and amino compound having at least one -NH- group;

(iv) at least one ester of a substituted car¬ boxylic acid;

(v) at least one polymeric dispersant;

(vi) at least one hydrocarbon substituted phenolic dispersant; and

(vii) at least one fuel soluble alkoxylated deriva¬ tive of an alcohol, phenol, or amine.

28. The composition of claim 23 also containing a free organic sulfonic acid.

29. The composition of claim 23 wherein the hydro¬ carbon-soluble alkali or alkaline earth metal containing composition is the sodium or potassium salt of a hydro¬ carbyl-substituted succinic acid.

30. The composition of claim 23 wherein (A) is the neutral salt of the hydrocarbon-soluble alkali or alkaline earth metal-containing composition.

31. A two-cycle oil comprising an oil of lubricating viscosity, a component which is a fatty acid of about 8 to about 22 carbon atoms or a component capable of generating a fatty acid of about 8 to about 22 carbon atoms and a hydro¬ carbon soluble succinic acid containing a hydrocarbyl deriva¬ tive on at least one of the carbons alpha to a carboxyl group wherein there are at least 30 carbon atoms in the hydrocarbyl group.

32. The two-cycle oil of claim 31 additionally contain¬ ing an aminophenol.

33. The two-cycle oil of claim 31 wherein the fatty acid is isostearic acid.

34. The composition of claim 31 wherein the source of the fatty acid is from the reaction product of a polyamine and a fatty acid.

35. A method of minimizing gelation of organic material in a two-cycle engine comprising having present with gasoline and an oil of lubricating viscosity, a minor amount of a hydrocarbon-soluble hydrocarbyl-substituted polycarboxylic acid.

36. The method of claim 35 wherein the oil of lubri¬ cating viscosity is a petroleum derived oil.

37. The method of claim 35 wherein the hydrocarbyl- polycarboxylic acid is a succinic acid derivative.

38. The method of claim 35 wherein the hydrocarbyl- substituted polycarboxylic acid contains from about 30 to about 150 carbon atoms in the hydrocarbyl group.

39. A method of reducing gelation in an internal combustion gasoline engine comprising including in the gasoline a hydrocarbon-soluble polycarboxylic acid.

40. The method of claim 39 wherein the oil contains the reaction product of a fatty acid and a polyamine.

41. The method of claim 40 wherein the fatty acid contains less than 22 carbon atoms.

42. The method of claim 40 wherein the fatty acid contains from 8 to 22 carbon atoms.

43. The method of claim 39 wherein the hydrocarbon- soluble polycarboxylic acid contains about 30 to about 150 carbon atoms.

44. The method of claim 39 wherein the hydrocarbon- soluble polycarboxylic acid contains about 30 to 150 carbon atoms and there is present a reaction product of a fatty acid and a polyamine.

45. The method of claim 44 wherein the oil is contacted in the engine with (A) at least one hydrocarbon-soluble alkali or alkaline earth metal containing composition con¬ taining at least 8 aliphatic carbon atoms.

46. The method of claim 45 wherein there is also present (B) at least one hydrocarbon-soluble ashless disper¬ sant.

47. The method of claim 39 wherein the lubricating oil is contacted with a phenolic compound.