US2765276A - Lubricating compositions - Google Patents

Description

United States Patent LUBRICATING COlVIPOSITIONS John L. Van Winkle, San Lorenzo, Edward R. Bell, Concord, and Rupert C. Morris, Berkeley, Calif., assignors to Shell Development Company, New York, N. Y., a corporation of Delaware No Drawing. Application May 19, 1955, Serial No. 509,682

11 Claims. Cl. 252-325 This invention relates to lubricants particularly suitable for use in equipment operating under extreme pressure, high speeds and wide temperature range conditions.

It is known that certain classes of compounds can improve various types of bases such as lubricating oils or fuel oils in certain specific properties. Thus, soaps or organic salts generally are regarded as being capable of imparting detergency to base lubricants, whereas compounds containing chlorine, sulfur, phosphorus or lead are capable of imparting extreme pressure characteristics to lubricants. The combination of additives wherein each additive exerts its influence without interfering with the function of other additives is rather diflicult to attain. In most cases, interference or co-reaction occurs negating the desirable properties of the additives involved.

It is an object of this invention to improve lubricants by addition thereto of a novel multifunctional additive. Another object of this invention is to produce improved lubricants of outstanding stability and extreme pressure properties. Another object of this invention is to prevent oxidation of lubricants and corrosion and wear of surfaces contacted by said lubricants. Other objects of this invention will be apparent from the following description of this invention.

It has now been discovered that the foregoing and related ends can be accomplished by addition to a lubricant a minor amount of an organic phosphorus compound having the general formula:

wherein X is a chalcogen element and preferably is either oxygen or sulfur, R is a hydrocarbyl radical containing at least one and preferably more than one halogen atom not more than four carbon atoms removed from the phosphorus atom, said radical R being directly linked to the phosphorus atom through a carbon atom, of which preferred'is when R is a C(Hal)3 radical wherein Hal stands for a halogen, e. g., chlorine or bromine; R and R can be hydrogen or the same or different hydrocarbyl radicals, preferably alkyl radicals; and Y can be (2) XH radical; (3) XR radical or (4)XZ wherein R R and X are the same as defined above, R is a hydrocarbyl radical, e. g., alkyl, cycloalkyl or aralkyl radical and Z is a salt forming cation such as an amine, preferably an aliphatic amine.

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The monoamido phosphono ester, which can be used as additives in compositions of this invention can be prepared by the methods described in our co-pending application, Serial No. 369,232, filed July 20, 1953, now U. S. Patent 2,712,029, of which the present application is a continuation-in-part. The acids or salts of the esters as described in the parent case can be prepared by any suitable means such as by pyrolysis of the ester to form the amido acid and if desired the acid can be converted to a salt by neutralizing the acid with an amine or a metal compound such as calcium hydroxide. The diamido or the other derivatives of the phosphono compounds of this invention can be prepared by reacting organo phosphorus dihalides (which have been described by Kinnear and Perren in the Journal of the Chemical Society, 1952, pages 3437 to 3445) with an amine. Prior to converting organo phosphorus dihalides of the type described by Kinnear and Perren to an amido derivative, one of the halides can be replaced by an ester, acid or other polar group or by a hydrocarbyl radical. If the Kinnear and Perren intermediate dihalide compounds are used as a starting material, the reaction can be generally carried out at low temperatures of from about -10 to about 20 C., and preferably at zero to 5 C., preferably in the presence of an HCl acceptor and an inert solvent such as benzene and the like.

Starting trivalent phosphorus compounds for the preparation of amido-phosphono additives of this invention include mono and di-esters of amido phosphites and thiophosphites such as mono and dialkyl, aryl or cycloalkyl esters of amido phosphite, which can be illustrated mono or dialkyl (C1 to C18) amidophosphites, e. g., mono and diisopropyl, mono and dibutyl, mono and di-Z-ethylhexyl and mono and dioctadecyl phosphites, mono or dicycloalkyl amido phosphites, e. g., mono or dicyclohexyl amido phosphite, 2-N,N-bis(2-ethylhexyl) amino-1,3,2-dioxaphospholane; acids or esters of amido halophosphites such as N-butylamido chloro acid phosphite, butyl N-Z-ethylhexyl amido chlorophosphite; amido dihalophosphites such as N,N-butylamido dichlorophosphite. Other starting phosphorus compounds include those described by Kinnear and Perren as well as various derivatives.

Suitable amines which can be employed in the preparation of the amides of the present invention include aliphatic amines, alicyclic amines, aromatic amines, heterocyclic amines and mixtures thereof having a total of not more than about 40 carbon atoms of which the mono and dialkylamines in which each alkyl group contains from 1 to 20 carbon atoms are preferred. Examples of such amines include primary or secondary saturated and unsaturated aliphatic amines, such as methyl allyl, propyl, butyl, 2-ethylhexyl, cetyl, dodecyl, oleyl and octadecylamines; alicyclic amines, such as cyclohexyl, methylcyclohexyl, cyclopentylamines and homologs and analogs thereof; aromatic amines, such as, aniline and naphthylamine; heterocyclic amines such as piperidine, morpholine and the like. 7

The following examples serve to illustrate the novel amides of the present invention and their preparation. It will be appreciated that the following examples are presented with the intent to illustrate rather than to limit the invention as it is defined in the hereto appended claims.

Example I.-n Butyl N,N Diisopropylamidotrichlaromethanephosphonate Dibutyl diisopropylamido phosphite was prepared by reacting diisopropyl amine with phosphorus trichloride, thereby obtaining diisopropylamidodichlorophosphite which was then reacted with sodium n-butoxide. resulting di-n-butyl N,N-diisopropylamidophosphite was added slowly, over a period of about one hour and with stirring, to excess carbon tetrachloride. The temperature of the reaction mixture was C. Stirring was continued at 0 C. for about 1 hour, after which the mixture was allowed to warm overnight. The warmed mixture was refluxed for 12 hours and then stirpped to 130 C., kettle temperature through a molecular still operating with the thimble at 76 C. The distillate had a refractive index, 121 of 1.4730. Analysis: Found, 7.3% hydrogen, 4.3% nitrogen, 10.6% phosphorous; calculated, 6.8% hydrogen, 4.13% nitrogen, 9.15% phosphor-us, all percentages being by weight.

Example II.N butylamidotrichloromethaizcplzosplzonic acid Example HI.Di-Z-ethylhexylamine salt of N-butyl a amidolrichlorometlzanephosphonic acid To the acid of Example Ii was added di-Z-ethylhexylamine in an amount sufiicient to neutralize the acid and the mixture was agitated at around 50 C. The salt formed was oil-soluble and had good extreme pressure properties. 1

Example lV.N,N'-di-n butyl trichloromethanephosphonic diamide About one mole of trichloromethanephosphonic dichloride was reacted with about two moles of n-butyl amine in the presence of triethylamine in a benzene solution and at around O5 C. The final product was recovered by the method described in Example 11.

Example V.Phenyl N-lmzylamidotrichloromezhanephosphomife About one mole of trichloromethanephosphonic dichloride was reacted with one mole of phenol in a henzene solution containing triethylamine as an HCl acceptor at around 05 C. The benzene solution was filtered, the benzene was flashed off and the product recovered was phenyltrichloromethanechlorophosphonate. The phenyl ester was reacted with a stoichiometric amount of n-butylamine under the above described conditions and recovered after filtering and removing the benzene was phenyl N-butylamidotrichloromethanephosphonate. Analysis of the product was: Found, 38.3% carbon, 4.6% hydrogen, 9.4% phosphorus, 31.8% chlorine and 4.05% nitrogen; calculated, 39.9% carbon, 4.54% hydrogen, 9.38% phosphorus, 32.2% chlorine and 4.23% nitrogen, melting point 85 C. and it boiled at 114 at 0.003 mm. pressure.

Example VI.n-Butylamidotrichloromethanephosplzolmte This compound was prepared in the same manner as the additive of Example V except that n-butanol was used in the place of phenol.

Other representative examples of novel amides of the present invention include the following: N-methylamidotri'chloromethanephosphonic acid, N-isopropylamidotrichloromethanephosphonic acid, N,N-dimethylamidotrichloromethanephosphonic acid, N,N-diisopropylamidotrichloromethanephosphonic acid, N,N-bis(2-ethylhexyl)- amidotrichloromethanephosphonic acid, N,N-dicyclo- The hexylamidotrichloromethanephosphonic acid; the methyl, ethyl, butyl, cyclohexyl, 2-ethylhexyl, benzyl and vinyl esters of said acids and the ammonium, C12C15 alkylamine, such as a Primenemanufactured by Rohm and Haas, di-2-ethylhexylamine and octadecylamine salts of said acids and the corresponding tribromo and triiodo amido phosphorus compounds.

The phosphorus compounds of this invention are generally used in amounts varying from about 0.01% to about 10% and preferably between about 0.1% and 5% by weight, depending upon the medium they are used in and use to which they are put.

In cases where the phosphorus compounds are not sufficiently soluble in the medium to which they are added, such as fuel oils, lubricating oils and the like, they can be eifectively dispersed or solubilized by means of alcohols, preferably branched chain alkanols. Alcohols of this type can be obtained by the 0x0 process described in the Oil and Gas Journal, June 9, 1949, and in the February 1953 issue of Petroleum Processing. Other types of alcohols such as the straight or branched chain fatty alcohols can be used as Well their thiol analogues. Examples of suitable alcohols are: hexyl, heptyl, octyl, nonyl, decyl, dodecyl, tridecyl, tetradecyl, octadecyl, benzyl, cyclohexyl, dimethyl cyclohexyl, 3,3,5-trimethylcyclohexyl, oleyl alcohols, sperm oil alcohol, wool grease alcohol, Oxo CsC1s alcohols (produced from olefins, carbon monoxide and hydrogen by the Oxo'reaction), petroleum alcohols, du Pont alcohols of the B21 to B series,'Archer-Daniels-Midland Adols, which are higher fatty alcohols. The thiol analogues of these alcohols such as described in U. S. Patent 2,638,448 and including isooctanethiol, decanethoil, octadecanethiol, tertiary tetradecanethiol, tertiary hexadecanethiol and the like or mixtures of said alcohols and/or thiols can be used with the phosphorus compounds in accordance with this invention.

The solubilizers of this invention can be used in amounts of from 0.5 to 10% and preferably from 1 to 5%, depending upon the type of phosphorus additive and base oil used in forming compositions of the invention. Generally, a relatively oil-insoluble phosphorus additive of this invention can be solubilized and stabilized from long periods of time such as in excess of 3 to 12 months under wide temperature conditions by use of the order of 3%, based on the total composition, of an alkanol and/ or alkanthiol as described.

Base oils to which agents of this invention are added may be selected from a variety of natural oils such as parafi'inic, naphthenic, and mixed base mineral oils having a viscosity range such as from at 100 F., SUS, to up to 250 SUS at 210 F. In addition, synthetic oils may be used such as polymerized olefins, alkylated aromatics; polyalkyl silicone polymers, e. g., liquid dimethyl silicone polymer and other silicone polymers; HzS-adducts of unsaturated ethers and thioethers, e. g.,

. H28 adduct of diallyl ether; esters, e. g., di(2-ethylhexyl) and used as the base oil. Also, the base can be gasoline,

fuel oil, hydraulic fluids, and the like.

Compositions of this invention were evaluated as extreme pressure agents by use of the Four-Ball Extreme Pressure Lubricating Tester similar in principle to the Boerlage apparatus described in the magazine, Engineering, volume 136, July 13, 1933. This apparatus comprises four steel balls arranged in a pyramid formation. The top ball is rotated by spindles against the three bottom balls which are clamped in a stationary ball holder. The balls'are immersed in the composition to be tested. Tests were run under conditions indicated in the following Table I and compared with other outstanding extreme pressure compounds.

5 TABLE I Four-ball evaluation of EP compositions [1620 R. P. M.; 1 minute, steel on steel, ambient temperature] Amount, Initial Base Oil Additive percentwt. Seizure Load, Kg.

1. SHAE 90, mineral 40-45 2. SAE 90, mineral Pass-Chlorinated sperm oil 10% 79 oil. reaction product contain g 7% S, 0.2% P and 0.3% CI. 3. Bpick Hypoid 56-71 01 Pb oleate 67 131cc gs'mmeml Chlorinated parafifin wax 3%: f 71 o Suliurized fish oil 20-25% 5. SAE 90, mineral {Examplel 0.4% 01 oil. Tridecyl aleohoL 1. G. SAE 90, mineral {Example 0 4% Cl 126441 s in 90 1 rifirldeesil iri 0 4; iii

7. minera ramp 9 s "s in 90 1 i i i r 01- 0 4 (ii 126441 minera xamp e 0 0' Trideeyl alcohol- 1.5% i 112 126 9. SAE 90, mineral Example 0.4% 01 100-112 10. EA 90, mineral Example V 0.4% 01 100-112 11. flSAE 10, mineral Examplel 0.42% 01 130-140 12. SAE 10, mineral N ,N-bis (Z-ethylhexyl) 0.2% Cl 150-160 oil. amido trichloromethaanephosphonic acid.

Results similar to those obtained with Compositions 5 to 12 in the Four-Ball EP Tester can be attained by substituting the amido-phosphono additives in said compositions with the amido-phosphono additives listed on columns 6 and 7 of the specification in concentrations of from 0.2% to 0.8% based on the halogen content of the additive.

Compositions of this invention can be combined with other additives in lubricants, such as anti-oxidants, corrosion inhibitors, wear reducer, blooming agents, pour point depressants or viscosity improvers, anti-foaming agents, e. g., dimethyl silicone polymer and the like.

Depending upon the primary additives used and conditions under which they are used, the amount of secondary additives used may vary from about 0.01% to about 2% or higher.

We claim as our invention:

1. A composition of matter comprising a major amount of a lubricating oil and a minor amount, sufficient to impart extreme pressure properties to said liquid oil, of a compound having the general formula wherein X is oxygen, R is a chloroalkyl radical linked directly to phosphorus through a carbon atom, Y is a polar radical selected from the groups consisting of (1) same as wherein R and R are selected from the group consisting if hydrogen and hydrocaIbyl radicals selected from the group consisting of alkyl and cycloalkyl radicals having from 1 to 20 carbon atoms; (2) -OH, (3) OR wherein R is a hydrocarbyl radical selected from the group consisting of alkyl and cycloalkyl radicals and (4) -OZ wherein Z is an ammonium radical.

2. A composition of claim 1 wherein X is oxygen and, R is aCCls radical.

3. A composition of claim 1 wherein the lubricating oil is a mineral lubricating oil.

4. A composition of matter comprising a major amount of mineral lubricating oil and a minor amount, sufiicient to impart extreme pressure to said oil, of a diarnide of a trichloromethane phosphonic acid derived from an amine having a total of not more than about carbon atoms.

5. A composition of matter comprising a major amount of mineral lubricating oil and a minor amount, sufiicient to impart extreme pressure to said oil of an alkyl amide of trichloromethane phosphonic acid derived from an alkylarnine having from 1 to 20 carbon atoms.

6. A composition of matter comprising a major amount of mineral lubricating oil and a minor amount, sufiicient to impart extreme pressure to said oil of an ester or" an alkyl amide of trichloromethane phosphonic acid derived from an alkylamine having from 1 to 20 carbon atoms.

7. A composition of matter comprising a major amount of mineral lubricating oil and a minor amount, sufiicient to impart extreme pressure to said oil, of a C3C18 alkyl amine salt of an alkyl amide of trichloromethane phosphonic acid derived from an alkylamine having from 1 to 20 carbon atoms.

8. A composition of matter comprising a major amount of mineral lubricating oil and from about 0.1% to about 10% of N-butyl amidotrichloromethane phosphonic acid.

9. A composition of matter comprising a major amount of mineral lubricating oil and from about 0.1% to about 10% of di-Z-ethylhexylamine salt of N-butyl amidotrichloromethane phosphonic acid.

10. A composition of matter comprising a major amount of mineral lubricating oil and from about 0.1% to about 10% of N,N-di-n-butyl trichloromethane phosphonic diamide.

11. A composition of matter comprising a major amount of mineral lubricating oil and from about 0.1% to about 10% of n-butyl N-butyl amido trichloromethanephosphonate.

References Cited in the file of this patent UNITED STATES PATENTS 2,573,568 Harman et al. Oct. 30, 1951 2,614,990 Harman et al. Oct. 21, 1952 2,683,691 Thorpe July 13, 1954 2,712,029 Van Winkle June 28, 1955

Claims (1)

1. A COMPOSITION OF MATTER COMPRISING A MAJOR AMOUNT OF A LUBRICATING OIL AND A MINOR AMOUNT, SUFFICIENT TO IMPART EXTREME PRESSURE PROPERTIES TO SAID LIQUID OIL, OF A COMPOUND HAVING THE GENERAL FORMULA