GB2062672A - Additive compositions comprising sulphurized alkyl phenol and high molecular weight dispersant - Google Patents

Abstract

Compositions comprising at least one sulfurized alkyl phenol and an oil- soluble carboxylic dispersant containing a hydrocarbon-based radical having a no. average mol. wt. of at least 1300 attached to a polar group are useful as lubricant additives. They impart improved dispersancy and viscosity modifying properties to the lubricants under severe engine operation conditions. Preferred compositions are those also containing ash-producing detergents such as mixtures of basic calcium and basic magnesium sulfonates.

Description

SPECIFICATION Additive compositions comprising alkyl phenol and high molecular weight dispersant This invention relates to new compositions of matter useful as lubricant additives, and to additive concentrates and lubricants containing them. In its broadest aspect, the invention is directed to compositions comprising: (A) At least one sulfurized alkyl phenol; and (B) an oil-soluble carboxylic dispersant characterized by the presence within its molecular structure of an aliphatic hydrocarbon-based radical having a number average molecular weight of at least 1300 attached to a polar group.

The increasing demands made on internal combustion engines in recent years have created a need for multi-purpose additives which in part increase stability and other desireable properties of the lubricants used in such engines under progressively more severe conditions. In particular, present-day internal combustion engines frequently operate at much higher temperatures than was previously the case. It is necessary to incorporate in the engine lubricant additives which improve its viscosity properties and disperse insoluble impurities to avoid their deposition on engine parts. Both the lubricating oil and the additives contained therein tend to degrade faster (through oxidation and other decomposition) at higher operating temperatures, the result being that there are more impurities to disperse and less additive capable of dispersing them and of maintaining the desired viscosity.One potential solution is to incorporate more additive in the lubricant, but this will only be effective over a long period if the additive is resistant to oxidative or similar degradation at the high temperatures of engine operation.

Component A of the compositions of this invention is at least one sulfurized alkyl phenol.

Sulfurized alkyl phenols and the methods of preparing them are known in the art and are disclosed, for example, in the following U.S. patents which are incorporated by reference herein: 2,139,766 3,285,854 2,198,828 3,538,166 2,230,542 3,844,956 2,836,565 3,951,830 In general, the sulfurized alkyl phenol may be prepared by reacting an alkyl phenol with a sulfurizing agent such as elemental sulfur, a sulfur halide (e.g., sulfur monochloride or sulfur dichloride), a mixture of hydrogen sulfide and sulfur dioxide, or the like. The preferred sulfurizing agents are sulfur and the sulfur halides, and especially the sulfur chlorides, with sulfur dichloride (SCI2) being especially preferred.

The alkyl phenols which are sulfurized to produce component A are generally compounds containing at least one hydroxy group and at least one alkyl radical attached to the same aromatic ring.

The alkyl radical ordinarily contains about 3100 and preferably about 620 carbon atoms. The alkyl phenol may contain more than one hydroxy group as exemplified by alkyl resorcinols, hydroquinones and catechols, or it may contain more than one alkyl radical; but normally it contains only one of each.

Compounds in which the alkyl and hydroxy groups are ortho, meta and para to each other, and mixtures of such compounds, are within the scope of the invention. Illustrative alkyl phenols are n-propylphenol, isopropylphenol, nbuWlphenqI, t-butylphenol, hexylphenol, heptylphenol, octylphenol, n-dodecylphenol, (propene tetramer)-substituted phenol, octadecylphenol, eicosylphenol, polybutene (molecular weight about 1000)-substituted phenol, n-dodecylresorcinol and 2,4-di-t-butylphenol. Also included are methylene-bridged alkyl phenols of the type which may be prepared by the reaction of an alkyl phenol with formaldehyde or a formaldehyde-yielding reagent such as trioxane or paraformaldehyde.

The sulfurized alkyl phenol is typically prepared by reacting the alkyl phenol with the sulfurizing agent at a temperature within the range of about 1 00-2500C. The reaction may take place in a substantially inert diluent such as toluene, xylene, petroleum naphtha, mineral oil, Cellosolve or the like.

If the sulfurizing agent is a sulfur halide, and especially if no diluent is used, it is frequently preferred to remove acidic materials such as hydrogen halides by vacuum stripping the reaction mixture or blowing it with an inert gas such as nitrogen. If the sulfurizing agent is sulfur, it is frequently advantageous to blow the sulfurized product with an inert gas such as nitrogen or air so as to remove sulfur oxides and the like.

The patents incorporated by reference hereinabove describe a number of methods for making suitable sulfurized alkyl phenols. A typical method is disclosed in the following example; all parts in the examples herein are by weight.

EXAMPLE 1 A reaction vessel is charged with 1000 parts of tetrapropene-substituted phenol which is heated to 380C. and blown with nitrogen. Sulfur dichloride, 290 parts, is added over 4 hours, during which time the temperature rises to 54OC. The mixture is blown with nitrogen for 2 hours at 1 470C., cooled to 1 360C. and diluted with 400 parts of mineral oil, and agitated for 2 hours at 950C. It is then filtered through a filter aid material to yield an oil solution of the desired sulfurized alkyl phenol which contains 4.88% sulfur.

Component B is an oil-soluble carboxylic dispersant whose characterizing feature, with respect to molecular structure, is the presence of a hydrocarbon-based radical having a number average molecular weight of at least 1300 attached to a polar group. As will be apparent from the description hereinafter, a dispersant molecule may under certain conditions contain more than one of either the hydrocarbonbased radical or the polar group. Dispersants of this type generally are also viscosity modifiers by reason of the presence of relatively high molecular weight hydrocarbon-based group.

As used herein, the term "Aliphatic hydrocarbon-based radical" denotes an aliphatic radical having a carbon atom directly attached to the remainder of the molecule and having predominantly hydrocarbon character within the context of this invention. Such radicals include the following: (1) Hydrocarbon radicals; that is, alkyl or alkenyl radicals.

(2) Substituted hydrocarbon radicals; that is, alkyl or alkenyl radicals containing non-hydrocarbon substituents which, in the context of this invention, do not alter the predominantly hydrocarbon character of the radical. Those skilled in the art will be aware of suitable-substituents (e.g., halo, nitro, hydroxy, alkoxy, alkylthio, carbalkoxy).

(3) Hetero radicals; that is, radicals 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, oxygen, nitrogen 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 aliphatic hydrocarbon-based radical.

The dispersants contemplated for use as component B are carboxylic dispersants, which are the reaction products of carboxylic acids or derivatives thereof with nitrogen-containing compounds having at least one

group such as amines, ureas and hydrazines, with organic hydroxy compounds such as phenols and alcohols, and/or with reactive metals or reactive metal compounds. U.S Patents 3,271,310; 3,272,746; and 3,381,022 describe the general features of the molecular structures and methods of preparation of various types of carboxylic dispersants. An illustrative preferred class thereof is disclosed in West German published application 2,808,105.

Various post-treatment products of the carboxylic dispersants are also useful as component B.

Illustrative post-treatment reagents include sulfur and sulfur compounds, urea, thiourea, guanidine, aldehydes, ketones, carboxylic acids, hydrocarbon-substituted succinic anhydrides, nitriles, epoxides, boron compounds and phosphorus compounds. The following U.S. patents are illustrative of suitable post-treatment reagents and methods: 3,036,003 3,282,955 3,493,520 3,639,242 3,087,936 3,312,619 3,502,677 3,649,229 3,200,107 3,366,569 3,513,093 3,649,659 3,216,936 3,367,943 3,533,945 3,658,836 3,254,025 3,373,111 3,539,633 3,697,574 3,256,185 3,403,102 3,573,010 3,702,757 3,278,550 3,442,808 3,579,450 3,703,536 3,280,234 3,455,831 3,591,598 3,704,308 3,281,428 3,455,832 3,600,372 3,708,522 4,161,475 All of the patents listed above are incorporated by reference herein for their pertinent disclosures of carboxylic dispersants and methods of making the same.

The preferred carboxylic dispersants for use as component B are those in which the acidic moiety is a substituted succinic acid c.f. U.K. Patent Specification No. 1 565627. Dispersants of this type are most often prepared by the reaction of an amine, alcohol, reactive metal or reactive metal compound with the appropriate substituted succinic acylating agent. Suitable acylating agents include the acids, anhydrides, esters and acyl halides, with the acids and anhydrides being preferred. The acylating agent may be prepared by the alkylation of maleic acid, fumaric acid, maleic anhydride or the like with a source of the desired hydrocarbon-based radical; for example, with a polymer containing at least one olefinic bond (optionally in the presence of chlorine) or with a polymer which contains at least one halogen (preferably chlorine) substituent.The number average molecular weight of the polymer should, as previously noted, be at least 1300. It is usually about 1 500-5000, but it may be as high as 1,000,000 or even higher in some instances. The ratio of weight average to number average molecular weight (IliiwlRn) may be about 1.56.0 and is usually about 1.5-4.0. The molecular weights of these polymers may be conveniently determined by gel permeation chromatography.

The polymers which are the sources of the hydrocarbon-based radicals are generally homopolymers and inter-polymers of polymerizable olefin monomers containing about 216 and usually about 2-6 carbon atoms. Illustrative monomers of this type are ethylene, propylene, 1 -butene, 2-butene, isobutene, 1-octene and 1 -decene.The polymer may also contain units derived from polyenes, including conjugated dienes such as 1 ,3-butadiene and isoprene; non-conjugated dienes such as 1 4-hexadiene, 1 4-cyclohexadiene, 5-ethylidene-2-norbornene and 1,6-octadiene; and trienes such as 1 -isopropylidene-3a,4,7 ,7a-tetrahydroindene, 1 -isopropylidenedicyclopentadiene and 2-(2methylene-4-methyl-3-pentenyl) [ 2.2.1 ] bicyclo-5-heptene.

A first preferred class of polymers comprises those of terminal olefins such as propylene, 1butene, isobutene and 1 -hexene. Especially preferred within this class are polybutenes comprising predominantly isobutene units. A second preferred class comprises terpolymers of ethylene, a C38 amonoolefin and a polyene selected from the group consisting of non-conjugated dienes (which are especially preferred) and trienes. Illustrative of these terpolymers is "Ortholeum 2052" manufactured by E. I. du Pont de Nemours s 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 100 ml. of carbon tetrachloride at 300 C.).

Methods for the preparation of the substituted succinic acid or anhydride are well known in the art and need not be described in detail herein. The mole ratio of the polymer to the maleic acid or anhydride may be equal to, greater than or less than 1, depending on the type of dispersant product desired. It is often preferred, however, to employ proportions such that the dispersant will contain an average of at least 1.3 succinic moieties per polymeric moiety; such dispersants are termed "polysuccinated dispersants". Especially preferred are polysuccinated dispersants containing about 1.4-3.5 succinic groups and most desirably about 1.5-2.5 succinic groups per polymer group.

The carboxylic dispersant is prepared by reacting the substituted succinic acid, anhydride or other acylating agent with at least one nitrogen compound, hydroxy compound, reactive metal or reactive metal compound, or mixture of any of the foregoing. Particularly preferred dispersants are those in which the succinic acylating agent is reacted with at least one amine or, in any order, with the combination of at least one amine and at least one alcohol; suitable amines and alcohols are described hereinafter.

Suitable nitrogen compounds are those characterized by a radical of the structure

wherein the two remaining valences of nitrogen are satisfied by hydrogen, amino or organic radicals bonded to said nitrogen atom through direct carbon-to-nitrogen linkages. These compounds include aliphatic, aromatic, heterocyclic and carbocyclic amines as well as substituted ureas, thioureas, hydrazines, guanidines, amidines, amides, thioamides, cyanamides and the like.

Among the amines useful in preparing the dispersant are monoamines. These monoamines can be secondary, i.e., those containing only one hydrogen atom bonded directly to an amino nitrogen atom.

Preferably, however, they contain at least one primary amino group, i.e., a group wherein an amino nitrogen atom is directly bonded to two hydrogen atoms. The monoamines are generally substituted with C,~30 hydrocarbon-based radicals. Preferably these hydrocarbon-based radicals are aliphatic in nature and free from acetylenic unsaturation and contain 110 carbon atoms. Saturated aliphatic hydrocarbon radicals containing 110 carbon atoms are particularly preferred.

Among the preferred monoamines useful in making the dispersant are those of the general formula HNR1R2, wherein R1 is an alkyl radical of up to ten carbon atoms and R2 is hydrogen or an alkyl radical of up to ten carbon atoms. Other preferred monoamines are aromatic monoamines of the general formula HNR3R4 wherein R3 is a phenyl, alkylated phenyl, naphthyl or alkylated naphthyl radical of up to ten carbon atoms and R4 is a hydrogen atom, an alkyl radical of up to 10 carbon atoms, or a radical similar to R3. Examples of suitable monoamines are ethylamine, diethylamine, n-butylamine, din-butylamine, allylamine, isobutylamine, cocoamine, stearylamine, laurylamine, methyllaurylamine, oleylamine, aniline, methylaniline, N-methylaniline, diphenylamine, benzylamine, tolylamine and methyl-2-cyclohexylamine.

Hydroxy amines are also included in the class of useful monoamines. Such compounds are the hydroxyhydrocarbonyl-substituted analogs of the afore-described monoamines. Preferred hydroxy monoamines have the formulas HNRSRB and HNR7R8, wherein R5 is an alkyl or hydroxy-substituted alkyl radical of up to 10 carbon atoms, R6 is hydrogen or a radical similar to R5, R7 is a hydroxy-substituted phenyl, alkylated phenyl, naphthyl or alkylated naphthyl radical of up to 10 carbon atoms, and R8 is hydrogen or a radical similar to R7, at least one of R5 and R6 and at least one of R7 and R8 being hydroxysubstituted.

Suitable hydroxy-substituted monoamines include ethanolamine, di-3-propanolamine, 4- hydroxybutylamine, diethanolamine, N-methyl-2-propylamine, 3-hydroxyaniline, Nhydroxyethylethylene diamine, N,N-di(hydroxypropylene diamine and tris(hydroxymethyl)methylamine.

While in general hydroxy amines containing only one hydroxy group will be employed as reactants, those containing more can also be used.

Heterocyclic amines are also useful in making the dispersant, provided they contain a primary or secondary amino group. The heterocyclic ring can also incorporate unsaturation and can be substituted with hydrocarbon radicals such as alkyl, alkenyl, aryl, alkaryl or aralkyl. In addition, the ring can also contain other hetero atoms such as oxygen, sulfur, or other nitrogen atoms including those not having hydrogen atoms bonded to them. Generally, these rings have 310, preferably 5 or 6, ring members.

Among such heterocycles are aziridines, azetidines, azolidines, pyridines, pyrroles, piperidines, imidazoles, indoles, piperazines, isoindoles, purines, morpholines, thiamorpholines, N-aminoalkyl morpholines, N-aminoalkyl thiamorpholines, azepines, azocines, azonines, azecines and tetrahydro-, dihydro- and perhydro-derivatives of each of the above. Preferred heterocyclic amines are the saturated ones with 5- and 6-membered rings, especially the piperidines, piperazines and morpholines described above.

Polyamines are preferred for preparing the dispersant. Among the polyamines are alkylene polyamines (and mixtures thereof) including those having the formula

wherein N is an integer between about 1 and 10, preferably between 2 and 8; each A is independently hydrogen or a hydrocarbon or hydroxy-substituted hydrocarbon radical having up to about 30 atoms; and R9 is a divalent hydrocarbon radical having about 1-18 carbons. Preferably A is an aliphatic radical of up to about 10 carbon atoms which may be substituted with one or two hydroxy groups, and R9 is a lower alkylene radical having 110, preferably 2-6, carbon atoms. Especially preferred are the alkylene polyamines wherein each A is hydrogen.Such alkylene polyamines include methylene polyamines, ethylene polyamines, butylene polyamines, propylene polyamines, pentylene polyamines, hexylene polyamines and heptylene polyamines. The higher homologs of such amines are related aminoalkyl-substituted piperazines are also included. Specific examples of such polyamines include ethylene diamine, triethylene tetramine, tris(2-aminoethyl)amine, propylene diamine, trimethylene diamine, hexamethylene diamine, decamethylene diamine, octamethylene diamine, di(heptamethylene) triamine, tripropylene tetramine, tetraethylene pentamine, trimethylene diamine, pentaethylene hexamine, di(trimethylene) triamine, 2-heptyl-3-(2-aminopropyl)imidazoline, 1 ,3-bis(2- aminoethyl)imidazoline, 1 -(2-aminopropyl)piperazine, 1 ,4-bis(2-aminoethyl)piperazine and 2-methyl-1 - (2-aminobutyl)piperazine. Higher homologs, obtained by condensing two or more of the aboveillustrated alkylene amines, are also useful.

The ethylene polyamines, examples of which are mentioned above, are especially useful for reasons of cost and effectiveness. Such polyamines are described in detail under the heading "Diamines and Higher Amines" in Kirk-Othmer, Encyclopedia of Chemical Technology, Second Edition, Viol. 7, pp.

2239. They are prepared most conveniently by the reaction of an alkylene chloride with ammonia or by reaction of an ethylene mine with a ring-opening reagent such as ammonia. These reactions result in the production of the somewhat complex mixtures of alkylene polyamines, including cyclic condensation products such as piperazines. Because of their availability, these mixtures are particularly useful in preparing the dispersant. Satisfactory products can also be obtained by the use of pure alkylene polyamines.

Hydroxy polyamines, e.g., alkylene polyamines having one or more hydroxyalkyl substituents on the nitrogen atoms, are also useful in preparing the dispersants. Preferred hydroxyalkyl-substituted alkylene polyamines are those in which the hydroxyalkyl group has less than about 10 carbon atoms.

Examples of such hydroxyalkyl-substituted polyamines include N-(2-hydroxyethyl)ethylene diamine, N,N'-bis(2-hydroxyethyl)ethylene diamine, 1 -(2-hydroxyethyl)piperazine, monohydroxypropylsubstituted diethylene triamine, dihydroxypropyltetraethylene pentamine and N-(3 hydroxybutyl)tetramethylene diamine. Higher homologs obtained by condensation of the aboveillustrated hydroxyalkyl-substituted alkylene amines through amino radicals or through hydroxy radicals are likewise useful.

Other amino compounds useful for preparing dispersants include aliphatic and aromatic aminosulfonic acids such as 2-amino-2-methylpropanesulfonic acid and anthranilic acid, and polyoxyalkylene polyamines such as the "Jeffamines" available from Jefferson Chemical Co.

The dispersant can also be prepared from hydrazine or an organo-substituted hydrazine of the general formula

wherein each R10 is independently hydrogen or a C1~3Q hydrocarbon radical, at least one R10 radical being hydrogen. Preferably, the others are C110 aliphatic groups. More preferably at least two R10 radicals are hydrogen, and most preferably at least two such groups bonded to the same nitrogen atom are hydrogen and the remaining ones are alkyl groups of up to 10 carbon atoms.Examples of suitable substituted hydrazines are methylhydrazine, N,N-dimethylhydrazine, N,N'-dimethylhydrazine, phenylhydrazine, N-phenyl-N1-ethylhydrazine, N-(p-tolyl)-N'-(n-butyl)hydrazine, N-(p-nitrophenyl)-Nmethylhydrazine, N,N'-di-(p-chlorophenyl)hydrazine and N-phenyl-N'-cyclohexylhydrazine.

Suitable organic hydroxy compounds include monohydric and polyhydric hydrocarbon-based alcohols such as methanol, ethanol, the propanols, butanols, pentanols, hexanols, heptanols, octanols, decanols, dodecanols, hexadecanols, etc., as well as the so-called fatty alcohols and their mixtures which are discussed in detail under the title "Higher Fatty Alcohols" in Encyclopedia Of Chemical Technology, Second Edition, Vol. 1, pp. 542-557.-Among such alcohols are lauryl, myristyl, cetyl, stearyl and behenyl alcohols.

Fatty alcohols containing minor amounts of unsaturation (e.g., no more than about two carbon-tocarbon unsaturated bonds per molecule) are also useful and are exemplified by palmitoleyl (C,6H300), oleyl (CX8H360) and eicosenyl (C20H400) alcohols.

Higher synthetic monohydric alcohols of the type formed by the Oxo process (e.g., 2-ethylhexyl), the aldol condensation, or by organoaluminum-catalyzed oligomerization of alpha olefins (especially ethylene), followed by oxidation, are also useful. These higher synthetic alcohols are discussed in detail in Encyclopedia of Chemical Technology, Vol. 1, pp. 560-569.

Also useful as organic hydroxy compounds are the alicyclic analogs of the above-described alcohols; examples are cyclopentanol, cyclohexanol and cyclododecanol.

Polyhydroxy compounds are also useful. These include ethylene, propylene, butylene, pentylene, hexylene and heptylene glycols wherein the hydroxy groups are separated by 2 carbon atoms; tri-, tetra penta-, hexa- and heptamethylene glycols and hydrocarbon-substituted analogs thereof (e.g., 2-ethyl- 1 ,3-trimethylene glycol, neopentyl glycol), as well as polyoxyalkylene compounds such as diethylene and higher polyethylene glycols, tripropylene glycol, dibutylene glycol, dipentylene glycol, dihexylene glycol and diheptylene glycol, and their monoethers.

Phenol, naphthols, substituted phenols (e.g., the cresols), and dihydroxyaromatic compounds (e.g., resorcinol, hydroquinone), as well as benzyl alcohol and similar dihydroxy compounds wherein the second hydroxy group is directly bonded to an aromatic carbon (e.g., HOC6H4CH2OH) are also useful, as are sugar alcohols of the general formula HOCH2(CH0H)15CH2OH such as glycerol, sorbitol, mannitol, etc. (described in detail in Encyclopedia of Chemical Technology, Vol. 2, pp. 569-588), and their partially esterified derivatives, and methylol polyols such as pentaerythritol and its oligomers (di- and tripentaerythritol, etc.), trimethylolethane and trimethylolpropane.

A further class of useful hydroxy compounds comprises the polyoxyalkylene compounds of the type commonly sold as demulsifiers. These include the "Ethomeens", "Ethoduomeens", "Pluronics", "Tergitols", "Tetronics", "Dow Polyglycols" and the like.

The preferred hydroxy compounds are alcohols containing up to about 40 aliphatic carbon atoms, particularly polyhydric alcohols containing about 210 carbon atoms and usually about 3-6 hydroxy groups (e.g., glycerol, pentaerythritol, sorbitol, mannitol, trimethylolethane and trimethylolpropane).

Pentaerythritol is especially preferred.

Illustrative reactive metal compounds which may be used to produce dispersants include lithium, oxide, lithium hydroxide, lithium carbonate, lithium pentyloxide, sodium oxide, sodium hydroxide, sodium carbonate, sodium methoxide, sodium propoxide, potassium oxide, potassium hydroxide, potassium carbonate, potassium methoxide, magnesium oxide, magnesium hydroxide, magnesium carbonate, magnesium methoxide, magnesium propoxide, magnesium salt of ethylene glycol monomethyl ether, calcium oxide, calcium hydroxide, calcium carbonate, calcium methoxide, calcium propoxide, calcium pentyloxide, zinc oxide, zinc hydroxide, zinc carbonate, zinc propoxide, strontium oxide, strontium hydroxide, cadmium oxide, cadmium hydroxide, cadmium carbonate, cadmium ethoxide, barium oxide, barium hydroxide, barium carbonate, barium ethoxide, barium pentyloxide, aluminum oxide, aluminum isopropoxide, cupric acetate, lead oxide, lead hydroxide, lead carbonate, tin oxide, tin butoxide, cobalt oxide, cobalt hydroxide, cobalt carbonate, cobalt pentyloxide, nickel oxide, nickel hydroxide, nickel chloride, nickel carbonate and chromium (lí) acetate.

The preparation of carboxylic dispersants useful as component B is illustrated by the following examples.

EXAMPLE 2 A mixture of 510 parts (0.28 mole) of polybutene (Mn = 1845; Mw = 5325) comprising principally isobutene units and 59 parts (0.59 mole) of maleic anhydride is heated to 1900 C. over 7 hours as 43 parts (0.6 mole) of gaseous chlorine is added beneath the surface. At 190-1 920C. an additional 11 parts (0.1 6 mole) of chlorine is added over 3.5 hours. The reaction mixture is stripped by blowing with nitrogen at 190--1930C. for 10 hours. The residue is a polybutene-substituted succinic anhydride having a saponification number of 87.

A mixture is prepared by the addition of 10.2 parts (0.25 equivalent) of a commercial mixture of ethylene polyamines having an average of 3-10 nitrogen atoms per molecule to 113 parts of mineral oil and 161 parts (0.25 equivalent) of the substituted succinic anhydride. The mixture is heated to 1 500 C. over 2 hours, stripped by blowing with nitrogen, and filtered to yield an oil solution of the desired dispersant.

EXAMPLE 3 A mixture of 1,000 parts (0.495 mole) of polybutene similar to that of Example 2 but having a Mn of 2020 and a Mw of 6049 and 115 parts (1.17 moles) of maleic anhydride is heated to 1840 C. over 6 hours as 85 parts (1.2 moles) of gaseous chlorine is added beneath the surface. At 184--1890C. an additional 59 parts (0.83 mole) of chlorine is added over 4 hours. The reaction mixture is stripped by blowing with nitrogen at 186-1 900 C. for 26 hours. The residue is a polybutene-substituted succinic anhydride having a saponification number of 87.

A mixture is prepared by the addition of 57 parts (1.38 equivalents) of the ethylene polyamine mixture of Example 2 to 1,067 parts of mineral oil and 893 parts (1.38 equivalents) of the substituted succinic anhydride. The mixture is heated to 1550 C. over 3 hours, stripped by blowing with nitrogen, filtered to yield an oil solution of the desired dispersant.

EXAMPLE 4 A mixture is prepared by the addition of 18.2 parts (0.433 equivalent) to the ethylene polyamine mixture of Example 2 to 392 parts of mineral oil and 348 parts (0.52 equivalent) of the substituted succinic anhydride of Example 3. The mixture is heated to 1 500C. over 1.8 hours, stripped by blowing with nitrogen, and filtered to yield an oil solution of the desired dispersant.

EXAMPLE 5 A mixture of 334 parts (0.52 equivalent) of the substituted succinic anhydride of Example 3, 548 parts of mineral oil, 30 parts (0.88 equivalent) of pentaerythritol and 8.6 parts (0.0057 equivalent) of Dow Polyglycol 112-2 demulsifier is heated to 2100 over 8.2 hours. It is then cooled to 1 900C. and 8.5 parts (0.2 equivalent) of the ethylene polyamine mixture of Example 2 is added. The mixture is stripped by blowing with nitrogen at 2050C. for 3 hours and filtered to yield an oil solution of the desired dispersant.

EXAMPLE 6 A substituted succinic anhydride is prepared by the procedure of Example 2, using a similar polybutene with a Mn of 1457 and a Mw of 5808. A mixture of 5500 parts of this anhydride, 3000 parts of mineral oil and 236 parts of the ethylene polyamine mixture of Example 2 is heated at 1 55-1 650C. for 2 hours, stripped by blowing with nitrogen at 1 650C. for 1 hour, and filtered to yield an oil solution of the desired dispersant.

EXAMPLE 7 A product is prepared by the procedure of Example 5 from 1 equivalent of the substituted succinic anhydride of Example 3,18 equivalents of pentaerythritol, 0.2 equivalent of the ethylene polyamine mixture of Example 2, and mineral oil in an amount to afford a 30% solution of the product in oil.

EXAMPLE 8 A product is prepared by the procedure of Example 3 using a substituted succinic anhydride prepared by the reaction of 98 parts of maleic anhydride with 5670 parts of a 10% solution of "Ortholeum 2052" in mineral oil.

EXAMPLES 926 The procedure of Example 2 is repeated using the reactants and relative amounts listed in Table I.

TABLE I Ratio of Substituted Succinic Succinic Anhydride Percent Example Anhydride of Other Reactant(s) to Other Reactant(s) Mineral Oil 9 Example 3 ZnO:polyamines of Ex. 2 1:0.5:0.5 (equivalents) 50% 10 Example 2 trie(2-Aminoethyl)amine 2:1 (moles) 50% 11 Example 3 Imino-bis-propylamine 2:1 (moles) 40% 12 Example 2 Hexamethylene diamine 1:2 (moles) 40% 13 Example 2 1-(2-Aminoethyl)-2-methyl-2- 1:1 (equivalents) 40% imidazoline 14 Example 2 N-Aminopropylpyrroolidone 1:1 (moles) 40% 15 Example 2 N,N-Dimethyl-1,3-propylene 1:1 (equivalents) 40% diamine 16 Example 2 N-(2-hydroxyethyl)-ethylene 1:1 (equivalents) 40% diamine 17 Example 2 1-Amino-2-propanol 1:1 (equivalents) 40% 18 Example 2 Ethylene diamine 1:4 (equivalents) 40% 19 Example 2 1,3-Propylene diamine 1:1 (moles) 40% 20 Example 2 2-Pyrrolldone 1:1.1 (moles) 20% 21 Example 2 Urea 1: :0.625 (moles) 50% 22 Example 6 Diethylene triamine 1:1 (moles) 50% 23 Example 6 Triethylene tetramine 1:0.5 (moles) 50% 24 Example 6 Aminoglycol 1:1 (moles) 50% 26 Example 6 Ethanolamine 1:1 (moles) 45% 27 example 6 trie(Hydroxymethyl)amino 10:1:7 (equivalents) 55% methane:polyamines of Ex. 2 In Example 9 the ZnO is added with water to the polybutene-substitued succinic anhydride-mineral oil mixture at 78 C the mixture is heated at 95 C. for 4 hours, and then the preparation is completed according to the general procedure set forth in Example 2.

In general, the compositions of this invention comprise about 0.33.0 parts by weight of component A per part of component B. These proportions are of active chemicals; that is they disregard any diluent such as mineral oil. The preferred proportions are about 0.31.0 part of component A per part of component B.

As previously indicated, the compositions of this invention are also useful as additives for lubricants, in which they function primarily as dispersants and viscosity modifiers. They are particularly useful for lubricating machinery which operates at relatively high temperatures, and are effective over a wide range of concentrations. Moreover, they frequently result in a decrease in the amount of oxidation inhibiting additives (examples of which are listed hereinafter) which must be incorporated in the lubricant.

The compositions can be employed in a variety of lubricants based on diverse oils of lubricating viscosity, including natural and synthetic lubricating oils and mixtures thereof. These lubricants include crankcase lubricating oils for spark-ignited and compression-ignited internal combustion engines, including automobile and truck engines, two-cycle engines, aviation piston engines, marine and railroad diesel engines, and the like. They can also be used in gas engines, stationary power engines and turbines and the like. Automatic transmission fluids, transaxle lubricants, gear lubricants, metal-working lubricants, hydraulic fluids and other lubricating oil and grease compositions can also benefit from the incorporation therein of the compositions of the present invention.

Natural oils include animal oils and vegetable oils (.e.g., castor oil, lard oil) as well 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 base oils.Synthetic lubricating oils include hydrocarbon oils and halo-substituted hydrocarbon oils such as polymerized and interpolymerized olefins [e.g., polybutylenes, polypropylenes, propyleneisobutylene copolymers, chlorinated polybutylenes, poly( 1 -hexenes), poly( 1 -octenes), poly(l-decens), etc. and mixtures thereof]; alkylbenzenes (e.g., dodecylbenzenes, tetradecylbenzenes, dinonylbenzenes, di(2-ethylhexyl)benzenes, etc.); polyphenyls (e.g., biphenyls, 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 derivatives thereof where the terminal hydroxyl groups have been modified by esterification, etherification, etc. constitute another class of known synthetic lubricating oils. These are exemplified by the oils prepared through polymerization of ethylene oxide or propylene oxide, the alkyl and aryl ethers of these polyoxyalkylene polymers (e.g., methylpolyisopropylene glycol ether having an average molecular weight of 1000, diphenyl ether of polyethylene glycol having a molecular weight of 5001000, diethyl ether of polypropylene glycol having a molecular weight of 1000-1500, etc.) or mono- and polycarboxylic esters thereof, for example, the acetic acid esters, mixed C3-C8 fatty acid esters, or the C13 Oxo acid diester of tetraethylene glycol.

Another suitable class of synthetic lubricating oils comprises the esters of dicarboxylic acids (e.g., phthalic acid succinic acid, alkyl succinic acids and 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 Cs to C12 monocarboxylic acids and polyols and polyol ethers such neopentyl glycol, trimethylolpropane, 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-2-ethylhexyl) silicate, tetra-(p-tert-butylphenyl) silicate, hexa-(4-methyl-2-pentoxy)-disiloxane, poly(methyl)-siloxanes, poly(methylphenyl)siloxanes, etc.). Other synthetic lubricating oils include liquid esters of phosphorus-containing acids (e.g., tricresyl phosphate, trioctyl phosphate, diethyl ester of decylphosphonic acid, etc.), polymeric tetrahydrofurans and the like.

Unrefined, refined and rerefined oils (and mixtures of each with each other) of the type disclosed hereinabove can be used in the lubricant compositions 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 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 purification techniques are known to those of skill in the art such as solvent extraction, acid or base extraction, filtration, percolation, etc.Rerefined oils are obtained by processes similar to those used to obtain refined oils applied to 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 additives and oil breakdown products.

Generally, the lubricants of the present invention contain an amount of the composition of this invention sufficient to provide dispersancy and improve viscosity properties. Normally this amount will be about 0.05-10.0% by weight, and preferably about 0.15.0%, per 100 parts of lubricant In oils used under extremely adverse conditions, such as in marine diesel engines, the composition of this invention may be present in amounts up to about 20%.

The invention also contemplates the use of other additives in combination with the compositions of this invention. such additives include, for example, auxiliary detergents and dispersants of the ashproducing or ashless type, corrosion- and oxidation-inhibiting agents, pour point depressing agents, extreme pressure agents, color stabilizers and anti-foam agents. Particularly preferred embodiments of the invention are combinations of components A and B with (C) at least one ash-producing detergent, the weight ratio (active chemical) of component C to components A and B usually being about 0.05-1.0:1 and preferably about 0.1-0.5:1.

Ash-producing detergents useful as component C are exemplified by oil-soluble neutral and basic salts of alkali or alkaline earth metals with sulfonic acids (which are preferred), carboxylic acids, or organic phosphorus acids characterized by at least one direct carbon-to-phosphorus linkage such as those prepared by the treatment of an olefin polymer (e.g., polyisobutene having a molecular weight of 1000) with a phosphorizing agent such as phosphorus trichloride, phosphorus heptasulfide, phosphorus pentasulfide, phosphorus trichloride and sulfur, white phosphorus and a sulfur halide, or phosphorothioic chloride. The most commonly used salts of such acids are those of sodium, potassium, lithium, calcium, magnesium, strontium and barium, with calcium and magnesium being preferred.The natures of suitable ash-producing detergents will be apparent to those skilled in the art since suitable compositions are disclosed in many patents and publications.

The term "basic salt" is used to designate metal salts wherein the metal is present in stoichiometrically larger amounts than the organic acid radical. The commonly employed methods for preparing the basic salts involve heating a mineral oil solution of an acid with a stoichiometric excess of a metal neutralizing agent such as the metal oxide, hydroxide, carbonate, bicarbonate, or sulfide at a temperature above 500 C. and filtering the resulting mass. The use of a "promoter" in the neutralization step to aid the incorporation of a large excess of metal likewise is known.Examples of compounds useful as the promoter include phenolic substances such as phenol, naphthol, alkylphenol, thiophenol, sulfurized alkylphenol, and condensation products of formaldehyde with a phenolic substance; alcohols such as methanol, 2-propanol, octyl alcohol, cellosolve, carbitol, ethylene glycol, stearyl alcohol, and cyclohexyl alcohol; and amines such as aniline, phenylenediamine, phenothiazine, phenyl-P- naphthylamine, and dodecylamine. A particularly effective method for preparing the basic salts comprises mixing an acid with an excess of a basic alkaline earth metal neutralizing agent and at least one alcohol promoter, and carbonating the mixture at an elevated temperature such as 60200 C.

Especially preferred as component C for certain purposes is a mixture of basic calcium and basic magnesium sulfonates, the weight ratio of calcium sulfonate to magnesium sulfonate being about 0.22.0:1 and most often about 0.5-1.5:1. Compositions containing such a mixture have been found to possess superior detergency and dispersancy properties under high temperature engine operating conditions such as those which prevail in diesel engines. Such properties are evidenced by a very low level of carbon and lacquer deposit formation.

Auxiliary ashless detergents and dispersants are so called despite the fact that, depending on its constitution, the dispersant may upon combustion, yield a non-volatile material such as boric oxide or phosphorus pentoxide; however, it does not ordinarily contain metal and therefore does not yield a metal-containing ash on combustion. Many types are known in the art and are disclosed in patents including those listed hereinabove with respect to component B. Also useful as auxiliary dispersants are interpolymers of oil-solubilizing monomers such as decyl methacrylate, vinyl decyl ether and high molecular weight olefins with monomers containing polar substituents, e.g., aminoalkyl acrylates or acrylamides and poly-(oxyethylene)-substituted acrylates. These may be characterized as "polymeric dispersants" and examples thereof are disclosed in the following U.S. patents which are incorporated by reference: 3,329,658 3,666,730 3,449,250 3,687,849 3,519,565 3,702,300 Extreme pressure agents and corrosion- and oxidation-inhibiting agents are exemplified by chlorinated aliphatic hydrocarbons such as chlorinated wax; organic sulfides and polysulfides such as benzyl disulfide, bis(chlorobenzyl)disulfide, dibutyl tetrasulfide, sulfurized methyl ester of oleic acid, sulfurized dipentene, and sulfurized terpene; phosphosulfurized hydrocarbons such as the reaction product of a phosphorus sulfide with turpentine or methyl oleate; phosphorus esters including principally dihydrocarbon and trihydrocarbon phosphites such as dibutyl phosphite, diheptyl phosphite, dicyclohexyl phosphite, pentylphenyl phosphite, dipentylphenyl phosphite, tridecyl phosphite, distearyl phosphite, dimethyl naphthyl phosphite, oleyl 4-pentylphenyl phosphite, polypropylene (molecular weight 500)-substituted phenyl phosphite, diisobutyl-substituted phenyl phosphite; metal thiocarbamates, such as zinc dioctyldithiocarbamate, and barium heptylphenyl dithiocarbamate; Group ll metal phosphorodithioates such as zinc dicyclohexylphosphorodithioate, zinc dioctylphosphorodithioate, barium di(heptylphenyl)phosphorodithioate, cadmium dinonylphosphorodithioate, and the zinc salt of a phosphorodithioic acid produced by the reaction of phosphorus pentasulfide with an equimolar mixture of isopropyl alcohol and n-hexyl alcohol.

The compositions of this invention can be added directly to the lubricant. Preferably, however, they are diluted with a substantially inert, normally liquid organic diluent such as mineral oil, naphtha, benzene, toluene or xylene, to form an additive concentrate. These concentrates usually contain about 2090% by weight of the composition of this invention and may contain, in addition, one or more other additives known in the art or described hereinabove.

Illustrative lubricants of this invention are listed in Table II. All amounts except those for the products of Examples 1, 3, 4 and 7 are exclusive of diluents such as mineral oil. The figures for "Weight proportions, component A: component B" are exclusive of mineral oil.

TABLE II Parts by weight Ingredient Lubricant A B C Mineral oil 92.92 91.75 8825 Product of Example 1 1.50 1.17 1.09 Product of Example 3 2.50 Product of Example 4- - 2.50 Product of Example 7 - - 7.14 Reaction product of polybutenyl (mol. wt.

about 1000) succinic anhydride with pentaerythritol and ethylene polyamine mixture) - 1.38 Basic calcium petroleum sulfonate 0.67 0.53 1.32 Basic magnesium petroleum sulfonate 0.59 0.49 Zinc dialkylphosphorodithioate 1.18 1.16 1.19 Alkyl fumarate-vinyl acetate-vinyl ether terpolymer - 021 0.14 Sulfur- and methylene-bridged polybutenyl (mol. wt. about 2000) phenol 0.54 - "Ortholeum 2052" - 0.80 0.52 Sulfurized alkyl cyclohexenecarboxylate 027 Tetrapropenyl succinic anhydride 0.27 Poly(alkylene oxide) demulsifier) 0.10 - Hindered phenol antioxidant - 0.01 0.01 Silicone anti-foam agent 0.011 0.01 0.007 Weight proportions, component A: component B 0.93 0.75 0.37

Claims (23)

1. A multi-component composition comprising: (A) At least one sulfurized alkyl phenol; and (B) an oil-soluble carboxylic dispersant characterized by the presence within its molecular structure of a hydrocarbon-based radical having a number average molecular weight of at least 1300 attached to a polar group.

2. A composition according to claim 1 wherein component A is prepared by reacting sulfur or a sulfur halide with at least one alkyl phenol in which the alkyl group contains about 3-1 00 carbon atoms.

3. A composition according to claim 2 wherein the reagent used for the preparation of component A is a sulfur chloride.

4. A composition according to claim 3 wherein the sulfur chloride is sulfur dichloride.

5. A composition according to claim 4 wherein the alkyl group in component A contains about 620 carbon atoms.

6. A composition according to any preceding claim wherein component B is produced by reacting, in any order, at least one substituted succinic acylating agent with at least one compound selected from the group consisting of compounds having at least one

group, organic hydroxy compounds, and reactive metals or reactive metal compounds; said substituted succinic acylating agent consisting of polyalkene-derived groups having a number average molecular weight of at least 1300 attached to succinic groups.

7. A composition according to claim 6 wherein component B has an average of at least 1.3 succinic groups present for each polyalkane-derived group.

8. A composition according to claim 7 wherein the acylating agent of component B is the substituted succinic acid or anhydride and is reacted with at least one amine or, in any order, with the combination of at least one amine and at least one alcohol.

9. A composition according to claim 8 wherein the number average molecular weight of the polyalkane-derived group is about 15005000 and its Mw/Mn value is about 1.56.0.

10. A composition according to claim 9 wherein the polyalkene-derived group is derived from polybutene comprising predominantly isobutene units, the amine is an alkylene polyamine, and the alcohol is pentaerythritol.

11. A composition according to claim 10 wherein the alkylene polyamine is an ethylene polyamine.

12. A composition according to claim 11 wherein the substituted succinic acid or anhydride is reacted solely with an ethylene polyamine mixture.

13. A composition according to claim 11 wherein the substituted succinic acid anhydride is reacted with an ethylene polyamine mixture and pentaerythritol.

14. A multi-component composition comprising: (A) At least one sulfurized alkyl phenol prepared by the reaction of sulfur dichloride with tetrapropene-substituted phenol; and (B) an oil-soluble dispersant prepared by the reaction of a polybutene-substituted succinic acid or anhydride in which the polybutene substituent has a number average molecular weight of about 15005000 and comprises predominantly isobutene units with a mixture of ethylene polyamines having an average of 3-10 nitrogen atoms per molecule, or, in any order, with said mixture of ethylene polyamines and pentaerythritol; said composition containing about 0.33.0 parts by weight of component A per part of component B.

15. A composition comprising the multi-component composition of any of claims 114 in combination with (C) at least one ash-producing detergent.

16. A composition according to claim 15 wherein component C is a mixture of basic calcium and basic magnesium sulfonates.

17. Additive concentrate comprising a substantially inert, normally liquid organic diluent and about 2090% by weight of a composition according to any of claims 114.

18. An additive concentrate comprising a substantially inert, normally liquid organic diluent and about 2090% by weight of a composition according to claim 1 5.

19. An additive concentrate comprising a substantially inert, normally liquid organic diluent and about 2090% by weight of a composition according to claim 16.

20. A lubricant comprising a major amount of a lubricating oil and a minor amount of a composition according to any of claims 114.

21. A lubricant comprising a major amount of a lubricating oil and a minor amount of a composition according to claim 15.

22. A lubricant comprising a major amount of a lubricating oil and a minor amount of a composition according to claim 16.

23. The invention in its several novel aspects.