US2874120A

US2874120A - Lubricating oil compositions

Info

Publication number: US2874120A
Application number: US604618A
Authority: US
Inventors: Forrest J Watson; Rupert C Morris; John L Van Winkle
Original assignee: Shell Development Co
Current assignee: Shell Development Co
Priority date: 1956-08-17
Filing date: 1956-08-17
Publication date: 1959-02-17
Anticipated expiration: 1976-02-17

Description

United States Patent LUBRICATING OIL COMPOSITIONS Forrest J. Watson and Rupert C. Morris, Berkeley, and John L. Van Winlrle, San Lorenzo, -Calif., assignors to Shell Development Company, New York, N. Y., a corporation of Delaware No Drawing. Application August 17,v 1956 Serial'No. 604,618

7 Claims. (Cl. 252--32.5)

This invention relates to lubricants, and particularly to lubricating compositions which are suitable. for use in equipment operating under extreme conditions, such as under extreme pressure, variable speed and wide temperature conditions.

It has been observed that certain types of phosphorus acids as defined more specifically hereinafter, impart outstanding extreme pressure properties to various lubricating compositions. However, these very effective agents are in general undesirable because they promote wear and cause corrosion.

The phosphorus acids referred to can be represented by the general formula:

Rl"(OH)z (I) wherein R is a polyhalohydrocarbyl radicaltand preferably a perchloroalkyl radical.

The art discloses that some of the undesirable properties of these acids can be overcome by forming secondary amine salts of these polyhalohydrocarbyl. phosphonic acids such as the di(2-ethyl-hexyl)amine salts of butyl trichloromethylphosphonic acid. However, in many cases these amine salts lack desired oil solubility and in storage tend to precipitate from the oil and form sludge.

It has now been discovered that certain amine salts of monochloroalkyl phosphonic acids, the. acid being represented by the formula:

RP(OH)2 (II) wherein R is a monochloroalkyl radical of from 1 to 4 and preferably 1 to 2 carbon atoms and the chlorine atom is in the alpha position relative to the phosphorus atom, possess outstanding extreme pressure and load carrying properties, have good oil solubility and are non-corrosive and non-staining when in contact with ferrous or nonferrous metals.

. 2,874,120 Patented Feb. .17, 1959 v ce chloroalkyl phosphonic acids are highly branched aliphatic primary amines or aliphatic secondary amines of at least 8 carbon atoms. Of thev highly branched aliphatic primary amines, the tertiary alkyl primary amines are preferred and they can be prepared by any suitable means such as described in the U. S. Office of the Publication Board Report No. 88843. Other highly branched primary amines can be prepared by converting primary branched chain olefins as fully described by P. W. Sherwood in the Oil and Gas Journal, June 9, 1949, page 71, and in the February 1953 issue of Petroleum Processing, to the corresponding nitriles and converting the nitrile to the amine by catalytic hydrogenation. Another method is to convert highly branched alcohols to the corresponding halides and to form the amines derived from the halide in the customary manner such as by reacting with ammonia.

It has been found that the tertiary alkyl primary amines, containing as the tertiary alkyl radical, the'radical' of polyisobutylene, polypropylene and mixtures thereof are particularly effective for the present purpose and they constitute a preferred class of amines for the practice of the invention. Accordingly, 1,I,3,3-tetramethylbutylamine (from the amination of diisobutylene), 1,1,3,3,5,5-hexamethylhexylamine (from triisobutylene), l,1,3,3,5,5,7,7- octamethyloctylamine (from tetraisobutylene) and 1,1,3, 3,5,5,7,7,9,9-decamethyldecylamine (from pentaisobutylene) are specific preferredamines, which are suitably used individually or as mixtures thereof. In addition to these tertiary alkyl' primary amines, tertiaryalkylmethyl primary amines, such as 2,2,4,4-tetramethylpentylamine, 2,4,4,6,o-hexamethylheptylamine and the like are suitable.

Other tertiary alkyl primary amines which can beused include the C and higher amines of this type mentioned in U. S. Patents 2,160,058, 2,606,923 and 2,611,782, such as tert-tridecylamine CzHt as well as isoheptyldiethylcarbinylamine, isooctylethylpropylcarbinylamine, and the like. Primary amines of this type are commercially available from Rohm and Haas Company under the trade name of Primenes, specific products being Primene 81-R, which is a mixture of primary alkylamines containing from about 12 to 15 carbon atoms and Primene J M-T, which is a similar tertiary alkylamine mixture containing an average of about 18 to 24 carbon atoms.

The following arethe properties of some amines which can be used to form the amine salts for use in lubricating compositions of this invention.

Table 1.Pr0perties Tertiary-octylamine Alkylamine 81-R Alkylamine J M-[ A1 A3 Formula t-CiH NH Principally t-C12H25NII2 to Principally tCisHavNHr to F015 31 2. J CuHuN 2. Molecular weight 128 Principally 185-227 Principally 269-353. Average molecular weight- 19 315 1.45s; 570% at 265-308" 0. (760 mm).

The acid portion used to make either the partial or full amine salt can be prepared by the method described by Barnard et al. in the Canadian Journal of Chemistry,

The amines which form effective salts-of-the mono- The secondary amines which can beused to form effective salts of the phosphorus acids are preferably those aliphatic and cycloaliphatic amines which contain from 10 to 36 carbon atoms. Illustrative of such amines are diamylamine, dihexylamine, di(2-ethylhexyl) amine, dioctylamine, didecylamine, didodecylamine,-- ditetradecylamine, dihexadecylamine, dioctadecylamine, dibromodioctadecylamine, isopropyloleylamine, diricinoleylamine, butylricinoleylarniria butyl 2 ethylhexylamine, dilauryl- OI-LA (III) and I o OH.A Rl

OILA (1v) wherein R is the same as defined in Formula II, and A is a long-chain highly branched aliphatic primary amine -or aliphatic secondary amine, having at least 8 carbon atoms and higher such as up to 30 carbon atoms in the molecule.

The amine salts of the monochloroalkyl phosphonic acids and mixtures thereof as described can be prepared by interacting the selected amine with monochloroalkylphosphonic acid in a suitable solvent if desired and under suitable conditions such as mixing at elevated temperature, stirring and heating. Salts produced in the foregoing or equivalent manner can be purified by re crystallization from suitable solvents or other means which will be apparent to those skilled in the art. For example, monochloromethylphosphonic acid was reacted at a temperature of around 100 C. with a mixture of t'CmHgqNHz t0 t'C24H49-NH2 in an amount sufiicient ot neutralize the total acidity of the acid, namely, one mole of the acid for two moles of the amine. Theprod uct is represented by the formula 0 Ol-LA: Clem-i OH.A:

or equivalently T 010 Hr- P OH. Al

or equivalently Another excellent non-corrosive extreme pressure additive having good oil solubility was prepared by using only half the stoichiometric amount of amine (A required to neutralize the total acidity of monochloromethanephosphonic acid. The product had the formula or equivalently The partially neutralized highly-branched-chain primary amine salts which are specifically preferred include: t'C1 H25NH t-C H NH to t-C15H31NH, t'C1 H3NH to t-C .;H NH dimethylneopentylcarbinyl amine, tert. tridecyl amine salts of monochloromethyl phosphonic acid, mono-alpha-chloroethylphosphonic acid.

The secondary amine salts which are specifically preferred include: di-2-ethylhexylamine, .di-1'isobutyl-3- methylbutylamine, didecylamine, dioctadecylamine, isopropyloleylamine, butyl-Z-ethylhexylamine, dicyclohexylamine salts of monochloromethylphosphonic acid monoalpha-chloroethylphosphonic acid.

The amine salts of the monochloroalkylphosphonic acids can be used in amounts ranging from about 0.01% to about 10% and preferably between 0.1% and 5% by weight.

Base oils to which agents of this invention are added may be selected from a variety of natural oils such as paraffinic, naphthenic and mixed base mineral oils having a viscosity range such as from 50 SUS at R, 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, other silicone polymers, H S-adducts of unsaturated ethers and thioethers, e. g. H 8 adduct of dialkyl ether, esters, e. g., di(2-ethylhexyl)sebacate. Mixtures of natural and synthetic oils can be used.

The outstanding properties which compositions of this invention possess is evidenced from the data presented in Table II. The L-13 rust test is described in the 1946 CRC Handbook published by the Co-Ordination Research Council; the four-ball test is described in Engineering, vol. 136, July 13, 1933; the bearing stain test consists of immersing a small clean Timken bearing in the composition being tested and heating the composition to C. for 65 hours. The bearing is removed, solvent washed and staining (10=bearing stain and 0=clean) observed in the cup and cone of the bearing. The reverse hypoid score load in H. P. is measured on the hypoid gear machine operated at 4000 R. P. M., giving results similar to the L-l9 test described in the CRC Handbook mentioned above.

T able ll SULFURIZED PALE OIL BASE ADDITIVE PRESENT IN AMOUNT OF 0.12% P Salt of amine A" of Table I 221-251 and monochloromcthyl phosphonic acid.

PALE OIL BASE SUS AT 100 F., PRESENT IN AMOUNT OF 0.12% 1 Salt 1 of amine A oi Table I 224-250 and monochloromethyl phosphonic acid.

Salt 2 of amine A of Table I andmonochloromethyl phos- 178-200 phonic acid. None 56- 63 DI-2-ETHYL HEXYL SEBAOATE BASE ADDITIVE PRESENT IN AN AMOUNT OF 0.12% P Salt 1 of amine A of Table I andmonochloromethyl phos- 200-224 phonic acid. None- 40- 45 1 Total acid neutralized.

3 Strong acidity neutralized only.

i Dibutyl derivative of polyoxypropyicne glycol having a viscosity of 1% Bus at 100 F.

In addition to the additives already described, lubricating oil compositions contemplated herein may contain other agents, such as pour-point depressants, oiliness agents, blooming agents, compounds for enhancing the viscosity index of the lubricating oil, peptizing agents, metal deactivators, etc.

We claim as our invention:

1. A lubricating oil composition comprising a major amount of a mineral lubricating oil and from about 0.01% to about by weight of an oil-soluble aliphatic amine salt of a monochloroalkylphosphonic acid containing from 1 to 4 carbon atoms in the alkyl group and wherein the chlorine atom is on the alpha carbon to the phosphorus atom, the amine portion of the salt being a branched-chain-aliphatic amine having from '8 to 24 carbon atoms and selected from the group consisting of primary and secondary amines,

2. A lubricating oil composition comprising a major amount of mineral lubricating oil and from about 0.01% to about 110% by weight of an oil soluble branched-chain- C -aliphatic primary amine salt of monochloro C alkyl phosphonic acid wherein the chlorine is on the alpha carbon to the phosphorus atom.

3. A lubricating oil composition comprising a major amount of mineral lubricating oil and from about 0.01% to about 10% by weight of an oil soluble branched-chain- C -aliphatic secondary amine salt of monochloro C alkyl phosphonic acid wherein the chlorine is on the alpha carbon to the phosphorus atom. t

4. A lubricating oil composition comprising a major amount of mineral lubricating oil and from about 0.1 to about 5% by weight of di-2-ethylhexylamine salt of monochloromethylphosphonic acid.

5. A lubricating oil composition comprising a major amount of mineral lubricating oil and from about 0.1 to about 5% by weight of a mixture of t-C H NH to t-C H NH amine salt of monochloromethylphosphonic acid.

6. A lubricating oil composition comprising a major amount of mineral lubricating oil and from about 0.1 to about 5% by weight of a mixture of t-C H NH to C H NH amine salt of monochloromethylphosphonic acid.

7. A lubricating composition according to claim 1, wherein the monochloroalkylphosphonic acid is alphachloroethylphosphonic acid.

References Cited in the file of this patent UNITED STATES PATENTS 2,169,185 Shoemaker Aug. 8, 1939 2,683,691 Thorpe July 13, 1954 2 1 Wi m -,---e---.-.----r-- an- 1 7

Claims

1. A LUBRICATING OIL COMPOSITION A MAJOR AMOUNT OF A MINERAL LUBRICATING OIL AND FROM ABOUT 0.01% TO ABOUT 10% BY WEIGHT OF AN OIL-SOLUBLE ALIPHATIC AMINE SALT OF A MONOCHLORALKYPHOSPHONIC ACID CONTAINING FROM 1 TO 4 CARBON ATOMS IN THE ALKYL GROUP AND WHEREIN THE CHLORINE ATOM IS ON THE ALPHA CARBON TO THE PHOSPHOROUS ATOM, THE AMINE PORTION OF THE SALT BEING A BRANCHED-CHAIN-ALIPHATIC AMINE HAVING FROM 8 TO 24 CARBON ATOMS AND SELECTED FROM THE GROUP CONSISTING OF PRIMARY AND SECONDARY AMINES.