US3655556A

US3655556A - Nitrogen-, phosphorus- and sulfur-containing lubricant additives

Info

Publication number: US3655556A
Application number: US63946A
Authority: US
Inventors: John Wight Allen
Original assignee: Lubrizol Corp
Current assignee: Lubrizol Corp
Priority date: 1970-08-14
Filing date: 1970-08-14
Publication date: 1972-04-11
Anticipated expiration: 1989-04-11

Abstract

Compositions useful as antioxidants, corrosion inhibitors and extreme pressure agents in lubricants are prepared from hydrazine or a substituted hydrazine, carbon disulfide, and the product obtained by reacting a hydroxy-substituted phosphorothioic acid triester with an inorganic phosphorus acid, oxide or halide and neutralizing a substantial portion of the acidic intermediate thus obtained with an amine.

Description

United States Patent Allen [151 3,655,556 [451 Apr. 11, 1972 [54] NITROGEN-, PHOSPHORUS- AND SULFUR-CONTAINING LUBRICANT ADDITIVES [72] inventor: John Wight Allen, Euclid, Ohio [7 3] Assignee: The Lubrizol Corporation, Wickliffe, Ohio [22] Filed: Aug. 14, 1970 2] Appl. No.2 63,946

[52] US. Cl ..252/32.7 E, 252/46.7, 252/389,

[51] int. Cl. ..Cl0m l/48 [58] Field of Search ..252/46.7, 32.7 E, 389, 400; 260/132, 127

[56] References Cited UNITED STATES PATENTS 2,966,462 12/1960 Spindt et al. ..252/32.7 E

3,182,021 5/1965 Asseff ..252/46.6 3,197,405 7/1965 Le Suer... ..252/32.7 E 3,197,496 7/1965 Le Suer ..252/32.7 X

Primary Examiner-Daniel E. Wyman Assistant Examiner-W. H. Cannon Attorney-Roger Y. K. l-lsu, William H. Pittman and James W. Adams, Jr.

[5 7] ABSTRACT 19 Claims, No Drawings NlTROGEN-, PHOSPHORUS AND SULFUR-CONTAINING LUBRICANT ADDITIV ES This invention relates to new compositions of matter useful as lubricant additives, particularly as corrosion and rust inhibitors and for the improvement of extreme pressure properties. More particularly, it relates to novel compositions of matter prepared by bringing into contact, under conditions such that a chemical reaction can take place, (A) a compound of the formula wherein each of R, R and R is hydrogen or a hydrocarbon or substituted hydrocarbon radical; (B) carbon disulfide; and (C) a composition prepared by forming an acidic intermediate by the .reaction of a hydroxy-substituted triester of a phosphorothioic acid with an inorganic phosphorus acid, oxide or halide and neutralizing a substantial portion of said acidic intermediate with an amine.

Modern lubricants, including engine oils, gear lubricants, automatic transmission fluids and the like, owe their efficiency in large part to the presence therein of numerous additives which improve various properties of the lubricant. Many of these additives, however, cause new problems of their own when they are added to the lubricant. For example, sulfurcontaining compounds are often used to improve extreme pressure properties of lubricants, especially gear oils and the like, but these sulfur compounds have a strong tendency to cause corrosion of metal parts, especially bearings which may contain copper, silver or other sulfur-reactive metals. Therefore, it is of continuing interest to develop lubricant additives which improve extreme pressure properties and at the same time inhibit corrosion and rust of the metal surfaces with which they come in contact.

A principal object of the present invention, therefore, is to prepare new compositions of matter suitable for use as lubricant additives.

A further object is to prepare lubricant additives which protect metal surfaces from rust and corrosion and which improve the extreme pressure properties of the lubricant.

Other object will in part be obvious and will in part appear hereinafter.

Component A in the compositions of this invention is hydrazine or a substituted hydrazine. The corresponding hydrazine hydrate may also be used. For reasons of economy and particular suitability, unsubstituted hydrazine (N H is preferred; but hydrazines substituted (either symmetrically or unsymmetrically) with from one to three hydrocarbon or substituted hydrocarbon radicals are also suitable. The term hydrocarbon radical" as used herein includes aliphatic, cycloaliphatic and aromatic (including aliphaticand cycloaliphatic-substituted aromatic and aromatic-substituted aliphatic and cycloaliphatic) radicals. it also includes cyclic radicals wherein the ring is completed through another portion of the molecule; that is, any two indicated substituents may together form a cycloalkyl radical.

The following are illustrative of hydrocarbon radicals within the scope of this invention. Where a named radical has several isomeric forms (e.g., butyl all such forms are included.

Methyl Benzyl Ethyl Cyclohexyl Propyl Cyclopentyl Butyl Methylcyclopentyl Hexyl Cyclopentadienyl Octyl Vinylphenyl Decyl lsopropenylphenyl Vinyl Cinnamyl Allyl Naphthyl Ethynyl Propargyl Phenyl Tolyl -CH2CII- Many obvious variations of these radicals will be apparent to those skilled in the art and are included within the scope of the invention.

The term hydrocarbon radical includes substituted hydrocarbon radicals. By substituted is meant radicals containing substituents which do not alter significantly the character or reactivity of the radical. Examples are:

Halide (fluoride, chloride, bromide, iodide) Hydroxy Ether (especially lower alkoxy) Keto Aldehyde Ester (especially lower carbalkoxy) Aminoacyl (amide) Nitro Cyano Thiocther Sulfoxy Sulfonc In general, no more than about three such substituent groups will be present for each 10 carbon atoms in the radical.

' Preferably, the hydrocarbon or substituted hydrocarbon radicals in the compounds of this invention are free from ethylenic and acetylenic unsaturation and have no more than about 30 carbon atoms, desirably no more than about 12 carbon atoms. A particular preference is expressed for lower hydrocarbon radicals, the word lower denoting radicals containing up to seven carbon atoms. Still more preferably, they are lower alkyl or aryl radicals, most often alkyl.

Examples of substituted hydrazines useful as component A are methylhydrazine, N,N-dimethylhydrazine, N,N-dimethylhydrazine, N,N,Nphenylhydrazine, N-phenyl-N-ethylhydrazine N-phenyl-N,N'-diethylhydrazine; N-(p-tolyl)-N'- (n-butyl)-hydrazine, N-(p-nitrophenyl)-N-methylhydrazine, N,N'-di(p-chlorophenyl)hydrazine and N-phenyl-N- cyclohexylhydrazine.

Component B is carbon disulfide. It may be used in the free state or in the form of carbon disulfide-producing compounds such as metal trithiocarbonates, dithiocarbamates or xanthates.

Component C is a composition prepared by neutralizing with an amine the acid formed by reacting a hydroxy-substituted phosphorothioic acid triester with an inorganic phosphorus acid, oxide or halide. Such compositions are disclosed in detail in U.S. Pat. No. 3,197,405, the disclosure of which is incorporated by reference herein.

The hydroxy-substituted triesters of phosphorothioic acids useful for the preparation of component C include principally those having the structural formula wherein each R is a hydrocarbon or substituted hydrocarbon radical (as defined hereinabove) or a hydroxy-substituted derivative thereof, at least one of the R radicals being hydroxy-substituted, and each X is sulfur or oxygen, at least one of the X radicals being sulfur. A preferred class of hydroxy-substituted triesters comprises those having the structural formula wherein R is a monovalent and R is a divalent hydrocarbon or substituted hydrocarbon radical. A convenient method for preparing such esters involves the reaction of a phosphorodithioic acid with an epoxide or a glycol. This reaction is known in the art; the following equations are illustrative.

Exemplary epoxides are ethylene oxide, propylene oxide, styrene oxide, a-methylstyrene oxide, p-methylstyrene oxide, cyclohexene oxide, cyclopentene oxide, 2,3-butene oxide, 1,2-butene oxide, 1,2-octene oxide, 3,4-pentene oxide, and 4- phenyl-l ,2-cyclohexene oxide. For reasons of economy, lower aliphatic epoxides and styrene oxides are preferred for use in this process.

Glycols which may be used include both aliphatic and aromatic dihydroxy compounds. Aliphatic glycols such as ethylene glycol, trimethylene glycol, tetramethylene glycol, hexamethylene glycol, propylene glycol, pentylene glycol, decamethylene glycol, diethylene glycol, triethylene glycol, and pentaethylene glycol are especially useful. Also suitable are aromatic dihydroxy compounds such as hydroquinone, catechol, resorcinol and l,2-dihydroxynaphthalenes.

Another convenient method for preparing the hydroxy-substituted triesters is described in U.S. Pat. No. 2,528,732 and comprises the addition of a phosphorodithioic acid to an unsaturated alcohol such as allyl alcohol, cinnamyl alcohol, or oleyl alcohol. Still another method described in US Reissue Pat. No. 20,411, involves the reaction of a metal phosphorothioate with a halogen-substituted alcohol.

The phosphorodithioic acids from which the hydroxy-substituted triesters can be derived are likewise well known. They are prepared by the reaction of phosphorus pentasulfide with an alcohol or a phenol. The reaction involves 4 moles of the alcohol or phenol per mole of phosphorus pentasulfide and may be carried out at about 50200 C. Thus, the preparation of 0,0-di-n-hexylphosphorodithioic acid involves the reaction of phosphorus pentasulfide with 4 moles of n-hexyl alcohol at about 100 C. for about 2 hours. Hydrogen sulfide is liberated and the residue is the desired acid.

The preparation of phosphoromonothioic acids may be effected by treatment of the corresponding phosphorodithioic acids with steam. Phosphorotrithioic acids and phosphorotetrathioic acids can be obtained by the reaction of phosphorus pentasulfide with mercaptans or mixtures of mercaptans and alcohols.

The reaction of phosphorus pentasulfide with a mixture of phenols or alcohols (e.g., isobutanol and n-hexanol in 2:1 weight ratio) results in phosphorodithioic acids in which the two organic radicals are different. Such acids likewise are useful for the preparation of component C.

The inorganic phosphorus reagent useful in the reaction with the hydroxy-substituted triesters of phosphorothioic acids is preferably phosphorus pentoxide. Other phosphorus oxides such as phosphorus trioxide and phosphorus tetroxide likewise are useful, as are phosphorus acids (e.g., phosphoric monobromophosphorus tetrachloride, ychloride and phosphorus triiodide).

Usually, from about 2 moles to about 5 moles of the triester for each mole of the inorganic phosphorus reagent. The preferred proportion of the triester is about 3-4 moles for each mole of the phosphorus reagent. The use of amounts of either reactant outside the limits indicated here results in excessive unused amounts of the reactant and is ordinarily not preferred.

The reaction of the hydroxy-substituted triester with the inorganic phosphorus reagent to produce the acidic intermediate can be effected simply by mixing the two reactants at a temperature above about room temperature, preferably above about 50 C. A higher temperature such as C. or C. may be used but ordinarily is unnecessary.

The reaction of the hydroxy-substituted phosphorothioic acid triester with the inorganic phosphorus reagent results in an acidic product. The chemical constitution of the acidic product depends to a large measure on the nature of the inorganic phosphorus reagent used. In most instances the product is a complex mixture the precise composition of which is not known. It is known, however, that the reaction involves the hydroxy radical of the triester and the inorganic phosphorus reagent. In this respect the reaction may be likened to that of an alcohol or a phenol with the inorganic phosphorus reagent. Thus, the reaction of the hydroxy-substituted triester with phosphorus pentoxide is believed to result principally in acidic phosphates, i.e., monoor diesters of phosphoric acid in which the ester radical is the residue obtained by the removal of the hydroxy radical of the phosphorothioic triester. The product may also contain phosphonic acids and phosphinic acids in which one or two direct carbon-to-phosphorous linkages are present.

The reaction between the hydroxy-substituted triester and a phosphorus oxyhalide or phosphoric acid is believed to result in similar mixtures of acidic phosphates, phosphonic acids and/or phosphinic acids. On the other hand, the reaction of the hydroxy-substituted triester with phosphorus tri-chloride or phosphorous acid is believed to result principally in acidic organic phosphites. Still others products may be obtained from the use of other inorganic phosphorus reagents. In any event, the product is acidic and as such is useful as the intermediate for the preparation of component C.

In the second step of the reaction sequence leading to component C. the above-described acidic intermediate is neutralized with an amine. The amine may be aliphatic, aromatic, cycle-aliphatic or heterocyclic. Examples are:

phosphorus oxn-Butylamine Stearylamine n-Hexylamine Eisosylamine n-Octylamine Behenylamine t-Octylamine Tetracosylamine n-Methyloctylumine Hexatriacontylamine Cyclopentylamine Pentahexacontylamine Cyclohexylamine Menthanediamine n-Decylamine Ethylenediamine n-Dodecylamine Di-n-dodecylamine Tri-n-dodecylamine Hexamethylenetetraminc Octamethylenediamine n-Dodecyltrimethylenediaminc Also useful are hydroxy-substituted amines such as the following:

Ethanolamine Diethanolamine Triethanolamine lsopropanolamine p-Aminophenol 4-Aminol -naphthol The preferred amines are aliphatic amines having about four to 30 carbon atoms, especially those containing at least about eight carbon atoms. A particular preference is expressed for primary amines containing tertiary alkyl groups, especially a commercially available mixture of C tertiary alkyl primary amines.

Among the hydroxy-substituted amines, a particular preference is expressed for secondary or tertiary aliphatic amines in which one of the substituents on nitrogen is a hydroxyalkylene or poly-(oxyalkylene) radical. Examples of the latter are N-4-hydroxybutyldodecylamine, N-Z-hydroxyethyl-n-octylamine, N-2-hydroxypropyldinonylamine, N,N- di-(3-hydroxypropyl)-t-dodecylamine, N-hydroxytriethoxyethyl-t-tetradecylamine, N-2-hydroxy-ethyl-t-dodecylamine, N-hydroxyhexapropoxypropyl-t-octadecylamine and N-5- hydroxypentyl-di-n-decy1amine. Amines of this type may be prepared by reacting an aliphatic primary or secondary amine with at least an equimolar amount of an epoxide, preferably in the presence of a highly basic catalyst such as sodium methoxide, sodamide, sodium metal or the like. Especially preferred are amines of this type wherein the alkyl substituents are tertiary alkyl radicals containing about 11-24 carbon atoms, It is frequently convenient and desirable to use a mixture of compounds of this type which may be prepared by the reaction of an epoxide with the commercial C,, tertiary alkyl primary amine mixture described above.

The relative proportions of the acidic intermediate and the amine used in the reaction should be such that a substantial portion of the acidic intermediate is neutralized. In most instances, enough amine should be used to neutralize at least about 50 percent of the acidic intermediate. Substantially neutral products such as are obtained by neutralization of at least about 90 percent of the acidity of the intermediateare desirable.

The neutralization of the acidic intermediate with the amine is in most instances exothermic and can be carried out simply by mixing the reactants at ordinary temperatures, preferably about 0-200 C. The chemical constitution of the neutralized product of the reaction depends to a large extent upon the temperature. Thus, at a relatively low temperature, such as less than about 80 C., the product comprises predominantly a salt of the amine with the acid. At a temperature above about 100 C., the product may contain amides, amidines, or mixtures thereof. The reaction of the acidic intermediate with a tertiary amine results only in a salt.

The preparation of compositions useful as component C is illustrated by the examples in the above-mentioned US. Pat. No. 3,197,405, and especially by the following.

EXAMPLE 1 Phosphorus pentoxide (64 grams, 0.45 mole) is added at 58 C. over 45 minutes to hydroxypropyl 0,0-di(4-methyl-2- pentyl)-phosphorodithioate (514 grams, 1,35 moles), which is prepared by treating di(4-methy1-2-pentyl)phosphorodithioic acid with 1.3 moles of propylene oxide at 25 C. The mixture is heated at 75 C. for 2% hours, mixed with a filter aid, and filtered at 70 C. To 217 grams (0.5 equivalent) of the filtrate there is added over minutes, at -60 C., 66 grams (0.35 equivalent) of a commercial aliphatic primary amine having an average molecular weight of 191 in which the aliphatic radical is a mixture of tertiary alkyl radicals containing 11-14 carbon atoms. The partially neutralized product contains 10.2% phosphorus and 1.5% nitrogen.

EXAMPLE 2 A mixture of 442 grams (0.925 mole) of hydroxypropyl 0.0-bis(dichlorophenyl)phosphorodithioate, prepared by the reaction of bis(dichlorophenyl) phosphorodithioic acid with 1.1 moles of propylene oxide at -90 C., and 43.6 grams (0.308 mole) of phosphorus pentoxide is heated at 140 C. for 0.5 hour, at 120l25 C. for 3 hours, and at 155-160 C. for

1 hour. The acidic intermediate thus obtained is neutralized by treatment at 1 10-120 C., for 2% hours, with 238 grams of a commercial aliphatic primary amine having an average molecular weight of 315 in which the aliphatic radical is a mixture of tertiary alkyl radicals containing from 18 to 22 carbon atoms. The neutralized product is filtered; the filtrate contains 5.4% phosphorus, 8.2% sulfur, 17.8% chlorine, and 1.5% nitrogen.

EXAMPLE 3 A mixture of 710 grams (5 moles) of phosphorus pentoxide and hydroxypropyl 0,0-di(4-methyl-2-pen- EXAMPLE 4 Phosphorus pentoxide 142 grams) is added at 75 C., over 1.2 hours, to 1,500 grams of hydroxypropyl 0,0'-di(4-methyl- 2-pentyl)phosphorodithioate. The mixture is heated at 75 C. for 3% hours and the liquid acidic product is separated. To 1,591 grams of the liquid there is added at 70 C., over 15 minutes, 700 grams of the aliphatic primary amine of Example 1. The product is filtered. The filtrate contains 7.95% phosphorus, 10.75% sulfur, and 2.21% nitrogen.

EXAMPLE 5 Phosphorus pentoxide (53 grams, 0.35 mole) is added to 430 grams (1.14 moles) of hydroxypropyl 0,0'-di(4-methyl-2- pentyl)-phosphorodithioate at -63 C. over 5.5 hours. The mixture is heated to 75-80 C. and held at that temperature for 2 hours. There is then added 219 grams of the commercial aliphatic primary amine of Example 1 at 3060 C. over 1.5 hours. The product is maintained at 50-60 C. for 1% hour and filtered. The filtrate contains 8.0% phosphorus, 10.4% sulfur, and 2.2% nitrogen.

EXAMPLE 6 Phosphorus pentoxide (33 grams) is added to 297 grams of hydroxyoctyl dicyclohexylphosphorodithioate (prepared by reacting dicyclohexylphosphorodithioic acid with one mole of 1,2-octene oxide at room temperature to 60 C.) at 75 C. over 45 minutes. The acidic reaction mixture is held at 75 C. for 4 hours and filtered. To 235 grams of the acidic filtrate there is added 115 grams of the commercial aliphatic primary amine of Example 1 at room temperature to C. over 15 minutes. The product contains 6.87% phosphorus, 9.00% sulfur, and 2.32% nitrogen.

EXAMPLE 7 Phosphorus pentoxide (55.8 grams, 0.39 mole) is added at 6090 C. to 1,358 grams (1.18 moles) of the hydroxypropyl ester of a di-(alkaryl)phosphorodithioic acid wherein the alkaryl groups are derived from a polyisobutenyl phenol in which the polyisobutenyl radicals have a molecular weight of about 350. The mixture is heated at 110 C. for 6 /2 hours and filtered. To 448 grams of the filtrate, there is added at 65-84 C., 100 grams of a commercial N-aminopropyl tallow amine having a nitrogen content of 7 percent and the resulting mixture is heated at C. for 40 minutes. The product contains 3.5% phosphorus, and 1.4% nitrogen.

EXAMPLE 8 Phosphorus thiochloride (PSCL 84.5 grams, 0.5 mole) is added to 592 grams (1.5 moles) of hydroxypropyl 0,0'-di(4- methyl-Z-pentyl)phosphorodithioate at 30 C. The acidic reaction mixture is heated to 85 C., held for 6 hours at this temperature, and mixed with 281 grams (1.5 moles) of the aliphatic primary amine of Example 1 at 30 C. to 60 C. The

product contains 6.85% phosphorus, 11.86% sulfur, and

2.18% nitrogen.

EXAMPLE 9 Phosphorus trichloride (46 grams, 0.33 mole) is added to 388 grams (1 mole) of hydroxypropyl 0,0'-di(4-methyl-2-pentyl) phosphorodithioate at room temperature over 30 minutes. The mixture is heated to 80 C./ 15 mm. over 3 hours. To the acidic residue (393 grams) there is added 117 grams of the aliphatic primary amine of Example 1 at room temperature to 1 5 45 C. The product contains 8.02% phosphorus, 12.72% sulfur, and 1.64% nitrogen.

EXAMPLE Twelve moles (2,292 grams) of the primary amine of Exampie 1 is placed in a reaction vessel and heated to 170 C. Sodium metal (0.6 gram) is added and then 528 grams (12 moles) of ethylene oxide is introduced into the reaction vessel over hours at l65175 C. Thereafter, the whole is stripped at 1 10 C./20 mm. Hg, diluted with '500 ml. of benzene, water- 25 washed, dried by azeotropic distillation, and filtered.

Five equivalents (2,330 grams) of phosphorus pentoxidetreated hydroxypropyl 0,0-di-(4-methyl-2-pentyl)phosphorodithioate prepared in a manner similar to that set forth in Example 1 is introduced into a reaction vessel and stirred. To it is added dropwise 1,180 grams (5 equivalents) of the N-2-hydroxyethyl substituted amine mixture prepared as described above, over a period of 0.75 hour. An exothermic reaction causes the temperature to rise to 60 C. After all of the amine has been added, the whole is stirred for 2 hours. The

resulting neutralized product contains 8.05% phosphorus, 2.03% nitrogen, and 10.16% sulfur.

The compositions of this invention are prepared by bringing the above-described components into contact under conditions such that a chemical reaction between them can take place (although, as explained hereinafter, it is not certain what reaction, if any, does take place). This may be done, for example, by heating and agitating or by merely agitating for a period of time sufficient for said reaction. The preparation is generally most conveniently carried out by maintaining a mixture of the three components at a temperature of about 25-l00bL C., preferably about -100 C. In general, no solvent is necessary, but a solvent inert to the reaction, such as a hydrocarbon, alcohol, ketone, ester or the like, may be used if so desired.

The proportions of the various reactants used are not critical. Generally, a mole ratio of component B to component A of about 2:1 is employed, but this ratio may be higher,

frequently up to 5:1, or may be lower on occasion. The weight ratio of component C to component A is generally between about 75:1 and 500:1.

The chemical structure of the products formed by the method of this invention is not known. The products may contain such species as dithiocarbamates, nitrogen-sulfur hetero- 6O cyclic compounds, thiocyanates and the like, as well as unreacted components A, B and C, in various proportions. They can be adequately defined only in terms of the process for their preparation.

The preparation of the compositions of this invention is illustrated by the following examples. All parts are by weight.

EXAMPLE 11 To a mixture of 1,320 parts of the product of Example 5 and 3.1 parts of 95% aqueous hydrazine is added over 2 minutes,

with stirring, 14.2 parts of carbon disulfide. The mixture is heated to -90 C. for about 2% hours, and then volatile materials are stripped at C./50 mm. The residue is filtered, yielding the desired product which contains 11.24% sulfur,

8.21% phosphorus and 2.32% nitrogen. 75

EXAMPLE 12 Following the procedure of Example 1 l, a product containing 11.38% sulfur, 8.33% phosphorus and 2.51% nitrogen is prepared from 1,320 parts of the compositions of Example 5, 9.3 parts of hydrazine hydrate and 28.3 parts of carbon disulfide.

EXAMPLE 1 3 Following the procedure of Example 1 l, a product containing 11.46% sulfur, 8.0% phosphorus and 2.75% nitrogen is prepared from 1,320 parts of the composition of Example 5, 18.6 parts of hydrazine hydrate and 56.6 parts of carbon disulfide.

EXAMPLE l4 EXAMPLE 15 Following the procedure of Example 14, a product is prepared from 1,320 parts of the composition of Example 5, 18.6 parts of hydrazine hydrate and 113.2 parts of carbon disulfide.

EXAMPLE 16 Following the procedure of Example 14, a product is prepared from 1,320 parts of the composition of Example 5, 19 parts of the hydrazine hydrate and 65 parts of carbon disulfide.

EXAMPLE 17 Following the procedure of Example 14, a product is prepared from 1,320 parts of the composition of Example 5, 23 parts of hydrazine hydrate and 74 parts of carbon disulfide. It contains 1 1.6% sulfur and 7.7% phosphorus.

EXAMPLE 18 Following the procedure of Example 14, a product is prepared from 1,807 parts of the composition of Example 5, 26 parts of hydrazine hydrate and 78 parts of carbon disulfide. It contains 8.15% phosphorus, 11.44% sulfur and 2.54% nitrogen.

EXAMPLE 19 Following the procedure of Example 14, a product is prepared from 7,920 parts of the composition of Example 3, 340 parts of carbon disulfide and parts of N,N-dimethylhydrazine.

EXAMPLE 20 Following the procedure of Example 14, a product is prepared from 7,920 parts of the composition of Example 6, 340 parts of carbon disulfide and 135 parts of N,N-dimethylhydrazine.

EXAMPLE 21 Following the procedure of Example 14, a product is prepared from 7,920 parts of the composition of Example 9, 340 parts of carbon disulfide and 166.5 parts of trimethylhydrazine.

EXAMPLE 22 Following the procedure of Example 14, a product is prepared from 7,920 parts of the composition of Example 10, 340 parts of carbon disulfide and 135 parts of ethylhydrazine.

The compositions of this invention as previously indicated, are useful in lubricants as oxidation and corrosion inhibitors and extreme pressure agents. As such, they can be employed in a variety of lubricating compositions based on diverse oils of lubricating viscosity, including natural and synthetic lubricating oils and mixtures thereof. The lubricating compositions contemplated include principally gear lubricants. However, crankcase lubricating oils for spark-ignited and compression-ignited internal combustion engines including automobile and truck engines, two-cycle engine lubricants, aviation piston engines, marine and railroad diesel engines, automatic transmission fluids, transaxle lubricants, metalworking lubricants, hydraulic fluids, and other lubricating oil and grease compositions can also benefit from the incorporation of the present compositions.

Natural oils include animal oils and vegetable oils (e.g., castor oil, lard oil) as well as solvent-refined or acid-refined 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, propylene-isobutylene copolymers, chlorinated polybutylenes, etc.); alkylbenzenes (e.g., dodecylbenzenes, tetradecylbenzene, dinonylbenzenes, di-(2-ethylhexyl)benzenes, etc.); polyphenyls (e.g., biphenyls, terphenyls, etc.); 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 1,000, diphenyl ether of polyethylene glycol having a molecular weight of 500-l,000, diethyl ether of polypropylene glycol having a molecular weight of 1,000-1 ,500, etc.) or monoand polycarboxylic esters thereof, for example, the acetic acid esters, mixed C -C fatty acid esters, or the C 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, maleic acid, azelaic acid, suberic acid, sebacic acid, fumaric acid, adipic acid, linoleic acid dimer, etc.) with a variety of alcohols (e.g., butyl alcohol, hexyl alcohol, dodecyl alcohol, 2ethylhexyl alcohol, pentaerythritol, 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 1 mole of sebacic acid with two moles of tetraethylene glycol and 2 moles of 2-ethylhexanoic acid, and the like. 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-(Z-ethyl-hexyl) silicate, tetra-(4-methyl-2-tetraethyl) silicate, tetra-(p-tert-butylphenyl) silicate, hexyl-(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 decane phosphonic acid, etc.), polymeric tetrahydrofurans, and the like.

In general, about 005-200 parts (by weight) of the composition of this invention is dissolved in 100 parts of oil to produce a satisfactory lubricant. The invention also contemplates the use of other additives in combination with the products of this invention. Such additives include, for example, detergents and dispersants of the ash-containing or ashless type, viscosity index improvers, auxiliary corrosion and oxidation inhibiting agents, pour point depressing agents, auxiliary extreme pressure agents, color stabilizers and anti-foam agents.

The ash-containing detergents are exemplified by oil-soluble neutral and basic salts of alkali or alkaline earth metals with sulfonic acids, carboxylic acids, or organic phosphorus acids characterized by at least one direct carbon-tophosphorus linkage such as those prepared by the treatment of an olefin polymer (e.g., polyisobutene having a molecular weight of 1,000) 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.

The term basic salt is used to designate metals 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 stiochiometric excess of a metal neutralizing agent such as the metal oxide, hydroxide, carbonate, bicarbonate, or sulfide at a temperature above 50 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-B-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, a phenolic promoter compound, and a small amount of water and carbonating the mixture at an elevated temperature such as 60200bL C.

Ashless detergents and dispersants are illustrated by the interpolymers of an oil-solubilizing monomer, e.g., decyl methacrylate, vinyl decyl ether, or high molecular weight olefin, with a monomer containing polar substitutents, e.g., amino-alkyl acrylate or poly-(oxyethylene)-substituted acrylate; the amine salts, amide, and imides of oil-soluble monocarboxylic or dicarboxylic acids such as stearic acid, oleic acid, tall oil acid, and high molecular weight alkyl or alkenyl-substituted succinic acid. Especially useful as ashless detergents are the acylated polyamines and similar nitrogen compounds containing at least about 54 carbon atoms as described in U.S. Pat. No. 3,272,746; reaction products of such compounds with other reagents including boron compounds, phosphorus compounds, epoxides, aldehydes, organic acids and the like; and esters of hydrocarbon-substituted succinic acids as described in U.S. Pat. No. 3,381,022.

Auxiliary extreme pressure agents and corrosion-inhibiting and oxidation-inhibiting agents are exemplified by chlorinated aliphatic hydrocarbons such as chlorinated wax; organic sultides and polysulfides such as benzyl disulfide, bis- (chlorobenzyl) disulfide, dibutyl tetrasulfide, sulfurized sperm oil, sulfurized methyl ester of oleic acid, sulfurized alkylphenol, sulfurized dipentene, and sulfurized terpene; oil-soluble xanthates and trithiocarbamates; 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, dihepthyl phosphite, dicyclohexyl phosphite, pentyl phenyl phosphite, dipentyl phenyl phosphite, tridecyl phosphite, distearyl phosphite, dimethyl naphthyl phosphite, oleyl 4-pentyl-phenyl phosphite,

polypropylene (molecular weight 500)-substituted phenyl phosphite, diisobutylrsubstituted phenyl phosphite; metal thiocarbamates, such as zinc dioctyldithiocarbamate, and barium heptylphenyl dithiocarbamate; Group 11 metal phosphorodithioates such as zinc dicyclohexylphosphorodithioate, zinc dioctylphosphorodithioate, barium di(heptylphenyl)phosphorodithioate, cadmium dinonylphosphorothioate, 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.

While the compositions of this invention may be added directly in the desired concentrations to lubricating oils prior to use, it is generally more convenient to prepare concentrates containing one or more additives including the compositions of this invention, dissolved in a small amount of oil, and subsequently to add these concentrates to the lubricating oil in the desired amounts.

and is operated at 2,500 r.p.m. for 4 hours at 180 F. The temperature is then reduced to 125 F. and the unit is stored for 7 days at this temperature, after which time the assembly is drained and dismantled. Inspection for corrosion is made of the cover, the most corroded bearing and the most corroded gear in the unit, and these parts are rated on a scale of 0-10, 0 representing severe corrosion and 10 representing no corrosion.

When tested by this method. lubricant A gave a cover rating of 9.8, a bearing rating of 10 and a gear rating of 9.9. Lubricant B gave a cover rating of 9.94, a bearing rating of 10 and a gear rating of 10.

What is claimed is:

1. A method for preparing a composition of matter suitable for use as a lubricant additive, which method comprises bringing into contact, under conditions such that a chemical reaction can take place, (A) a compound of the formula R1 R The compositions of typical concentrates are given in Table 1. in Table 11 are listed typical lubricating compositions of this invention. H

TABLE I Parts by weight Ingredient/Concentrate I II III IV V VI VII VIII IX Product of Example 13.. Product of Example 14 Product of Example 18.. Product of Example 20.. Zinc 0,0-di-(2-methyl-4-pentyl) dithioate Tetrapropenylsnecinic acid IIydroxypropyl tetrapropenylsuceinate/ tetrapropenylsuccinic acid mixture Tricresyl phosphate Alkylated bisphenolsolution in inert i l l I I I I I I D h I organic solvent) lfi-di-t-butyl-pm'esol Snlfurizedisobutene 2-olcyl 3.4.5.64etrahydropyrimidine.. Oleanlide-linolemuide mixture Silicone nnti-lolnn ngent Mineral oil TABLE II Parts by weight I ngredient/Lubricant A B C D E F G The corrosion-inhibiting properties of the compositions of this invention are shown by a Copper Corrosion Test which is a modification of ASTM procedure D130. In this test, a polished copper strip is submerged in the lubricant being tested at 250 F. for 3 hours, washed with isooctane and dried. 6 5 The copper strip is then examined to determine the amount of tarnish or corrosion, and is compared with a set of ASTM standard strips on a scale of l, 2, 3 and 4 representing slight tarnish, moderate tarnish, dark tarnish and corrosion respectively. When tested by this method, Lubricants A and B each gave ratings bordering between 1 and 2.

The Spicer Moisture Corrosion Test is used to determine the moisture corrosion resistance characteristics of gear lubricants contaminated by water in the normal environment of an automotive rear axle. in this test, a sealed rear axle assembly is charged with 2V2 pints of gear lubricant and 1 ounce of water wherein each of R, R and R is hydrogen or a hydrocarbon radical; (B) carbon disulfide; and (C) a composition prepared by forming an acidic intermediate by the reaction of a hydroxy-substituted triester of a phosphorothioic acid with an inorganic phosphorus acid, oxide or halide and neutralizing a substantial portion of said acidic intermediate with an amine.

2. A method according to claim 1 wherein component A is hydrazine or hydrazine hydrate.

3. A method according to claim 2 wherein the phosphorothioic acid triester of component C has the formula wherein each R is a hydrocarbon radical or a hydroxy-substituted derivative thereof, at least one of the R radicals being hydroxy-substituted, and each X is sulfur or oxygen, at least one of the X radicals being sulfur.

4. A method according to claim 3 wherein the phosphorothioic acid triester has the formula wherein R is a monovalent and R is a divalent hydrocarbon radical.

5. A method according to claim 4 wherein the inorganic phosphorus compound is a phosphorus oxide.

6. A method according to claim 5 wherein R is an alkyl radical and R is an alkylene radical.

7. A method according to claim 6 wherein R is lower alkyl and R is lower alkylene.

8. A method according to claim 7 wherein the amine of component C is an aliphatic amine having about four to 30 carbon atoms.

9. A method according to claim 8 wherein the amine is a tertiary alkyl primary amine containing at least about eight carbon atoms.

10. A composition of matter prepared by the method of claim 2.

11. A composition of matter prepared by the method of claim 4.

12. A composition of matter prepared by the method of claim 7.

13. A composition of matter prepared by the method of claim 8.

14. A composition of matter prepared by the method of claim 9.

15. A lubricating composition comprising a major amount of a lubricating oil and a minor amount, sufiicient to improve the lubricating properties thereof, of the composition of claim 10.

16. A lubricating composition comprising a major amount of a lubricating oil and a minor amount, sufficient to improve the lubricating properties thereof, of the composition of claim 1 1.

17. A lubricating composition comprising a major amount of a lubricating oil and a minor amount, sufiicient to improve the lubricating properties thereof, of the composition of claim 12 18. A lubricating composition comprising a major amount of a lubricating oil and a minor amount, sufficient to improve the lubricating properties thereof, of the composition of claim 13.

19. A lubricating composition comprising a major amount of a lubricating oil and a minor amount, sufficient to improve the lubricating properties thereof, of the composition of claim 14.

Claims

2. A method according to claim 1 wherein component A is hydrazine or hydrazine hydrate.
3. A method according to claim 2 wherein the phosphorothioic acid triester of component C has the formula wherein each R is a hydrocarbon radical or a hydroxy-substituted derivative thereof, at least one of the R radicals being hydroxy-substituted, and each X is sulfur or oxygen, at least one of the X radicals being sulfur.
4. A method according to claim 3 wherein the phosphorothioic acid triester has the formula wherein R4 is a monovalent and R5 is a divalent hydrocarbon radical.
5. A method according to claim 4 Wherein the inorganic phosphorus compound is a phosphorus oxide.
6. A method according to claim 5 wherein R4 is an alkyl radical and R5 is an alkylene radical.
7. A method according to claim 6 wherein R4 is lower alkyl and R5 is lower alkylene.
8. A method according to claim 7 wherein the amine of component C is an aliphatic amine having about four to 30 carbon atoms.
9. A method according to claim 8 wherein the amine is a tertiary alkyl primary amine containing at least about eight carbon atoms.
10. A composition of matter prepared by the method of claim 2.
11. A composition of matter prepared by the method of claim 4.
12. A composition of matter prepared by the method of claim 7.
13. A composition of matter prepared by the method of claim 8.
14. A composition of matter prepared by the method of claim 9.
15. A lubricating composition comprising a major amount of a lubricating oil and a minor amount, sufficient to improve the lubricating properties thereof, of the composition of claim 10.
16. A lubricating composition comprising a major amount of a lubricating oil and a minor amount, sufficient to improve the lubricating properties thereof, of the composition of claim 11.
17. A lubricating composition comprising a major amount of a lubricating oil and a minor amount, sufficient to improve the lubricating properties thereof, of the composition of claim 12.
18. A lubricating composition comprising a major amount of a lubricating oil and a minor amount, sufficient to improve the lubricating properties thereof, of the composition of claim 13.
19. A lubricating composition comprising a major amount of a lubricating oil and a minor amount, sufficient to improve the lubricating properties thereof, of the composition of claim 14.