US3499839A - Amine-stabilized iodine-containing lubricants - Google Patents

Description

United States Patent U.S. Cl. 25233.4 1 Claim ABSTRACT OF THE DISCLOSURE A lubricating oil having enhanced lubricating properties comprising a hydrocarbon lubricating oil, elemental iodine, a petroleum sulfonate, chlorinated wax and an amine.

This invention relates to addition of an amine to iodinecontaining lubricants for enhancing lubricating properties of the lubricants and for imparting performance and storage stability thereto.

The invention disclosed herein relates to the field of iodine-containing lubricant compositions. It has been rerently discovered that a small quantity of iodine in a carrier medium will act as an exceptionally effective oiliness agent to reduce friction occurring between moving surfaces. The iodine is particularly effective in improving lubricity of metal surfaces such as chrome, nickel, titanium, tungsten, and their alloys.

Roberts et al. Patent 3,228,880 discloses a lubricant comprising a charge transfer complex of iodine and an aromatic hydrocarbon which is especially useful on lubricating contacting surfaces at least one of which is 50 percent or more by weight titanium. Furey Patent 3,184,409 relates to (1) the use of elemental iodine in lubricating oil compositions for reducing friction between moving surfaces under boundary lubrication conditions and (2) elimination of iodine staining by incorporating certain compounds for that purpose. Furey et al. Patent 3,184,413 relates to polymeric lubricant composition containing iodine for improving antifriction, antiwear and extreme pressure properties. Bell et al. Patent 3,220,949 relates to the discovery that inclusion of ashless nitrogen-containing oil-soluble derivatives of alkenyl succinic anhydrides in iodine-containing lubricants effectively reduces the corrosive effect of the iodine on metallic surfaces.

Although the iodine-containing lubricants provide such a dramatic improvement in lubrication of chrome, nickel, tungsten and titanium metals and their alloys over lubricants not containing any iodine, at present, there are no commercially available iodine-containing lubricants on the marketfThe reason for commercial non-availability of the iodine-containing lubricants resides in the fact that iodine-containing lubricants lack sufiicient performance and storage stability. Upon standing for a short duration, effectiveness of the iodine as an oiliness agent in alu'bricant is lost with a consequent loss of lubricity.

It has now been discovered that an amine in an iodine containing lubricant will provide enhancement of lubricating properties of said lubricant as Well as performance and storage stability so necessary for commercial exploitation of these lubricants.

Lubricants of the present invention comprise a hydrocarbon oil by lubricating viscosity, iodine, a sulfonate, chlorinated wax, and other additives as, for example, oxidation inhibitors such as phenothiazine or phenyl-anaphthylamine and generally phenols, naphthols, sulfides and phosphides; detergent additives such as the barium salt of isononyl phenol sulfide and generally salts of phenols, of carboxylic acids, of sulfonic acids, and of alkyl phosphoric acids; pour-point depressants such as .copolymers of vinyl acetate with fumaric acid esters of 3,499,839 Patented Mar. 10, 1970 coconut oil alcohols and more broadly, alkyl naphthenates, polymers of long-chain acrylates, and multivalent metal soaps of various fatty acids; viscosity index improvers such as polymethacrylates; foam depressants such as siloxane derivatives; rust preventives such as fatty acids and their oil-soluble alkaline earth. salts, and multivalent metal salts of petroleum sulfonic acids; etc.

Suitable mineral or hydrocarbon oils of lubricating viscosity are the hydrocarbon lubricants obtained from petroleum. These products normally have viscosity in the range of 50 to 2000 Say-bolt Universal Seconds at F. The preferred hydrocarbon oils are those boiling above 300 F. and especially preferred are those boiling above 500 F. at atmospheric pressure. Solid products such as paraffin wax, semi-solid products such as petrolatum and greases, or relatively non-viscous products like kerosine, gas oil or fuel oil are contemplated as suitable mediums for the additives. Additionally, various synthetic lubricating oils made from esters, polysiloxanes, carbonates, formals, polyglycols, and the like may likewise be utilized as mediums. The term hydrocarbon oil of lubricating viscosity is not intended to be limited to any specific application but may include cutting oils, metal working oils, pneumatic equipment oils, spindle oils, gear oils, motor oils, etc.

Iodine can be utilized in its elemental state, as a charge transfer complex with a hydrocarbon, in a compound state, or as a component of a polymeric lubricating oil additive. The amount of iodine may range from 0.001 weight percent and up, but is generally in the raneg of about 0.001 to 10 weight percent and preferably in the range of about 0.01 to 0.5 weight percent.

Oil-soluble emulsifiers, such as sulfonates, which are derivatives of organic sulfonic acids, are used in amounts of about 1 to 25 Weight percent, and preferably in amounts of about 1 to 10 Weight percent. The sulfonates function to solubilize the iodine as well as the amine. Examples of other emulsifiers are the alkali-metal salts of carboxylic and sulfonic acids, monoesters of polyhydric alcohols, ether alcohols, and the various polyoxyethylene derivatives offatty acids.

Chlorinated wax and, generally, organic chlorine and sulfur compounds are used as extreme pressure additives. Chlorinated wax is used in an amount of about 1 to 25 Weight percent and preferably in the amount of about 1 to 10 Weight percent.

For more information on the various additives and applications of the lubricants containing such additives, reference is here made to the above-mentioned prior art patents, and the Kirk-Othmer Encyclopedia of Chemical Technology.

As was already pointed out, the present invention relates to the discovery that addition of an amine to an iodinecontaining lubricating composition will impart thereto performance and storage stability and will enhance lubrieating properties of the lubricant. Amines are added in an amount of about 0.001 to 10 weight percent and preferably in the amount of about 0.01 to 0.5 weight percent.

Preparation of a lubricating composition A typical lubricating composition was prepared by adding to a glass beaker 89.5 grams of oil having the following specification:

Sulfur, weight percent 0:32

Atmospheric distillation, F.:

IBP 601 The following ingredients were then added to the oil: 5 grams of a high molecular weight petroleum sulfonate; 5 grams of chlorinated wax; and 0.25 gram of elemental iodine.

The high molecular weight petroleum sulfonate had the following specifications:

Molecular weight 457 Sulfonates percent 62.0 Mineral oil do 32.5 Inorganic salt do 0.5 Water do 5.0 Specific gravity at 60 F. 1.02 Weight per gallon at 60 F 8.50 Furol viscosity at 210 F. 100

Flash point F 380 The chlorinated wax had a viscosity of 165 SUS at 210 F. and contained 41 to 42 weight percent chlorine.

The contents of the beaker were heated to about F. with constant stirring. After the iodine dissolved in the solution, heat was removed and 0.25 gram of triethanolamine was added with mixing.

To avoid formation of sludge, the sulfonate should be added before iodine, since the sulfonate acts to solubilize the iodine. The lower molecular weight amines are oil-insoluble and for that reason, should be added when a solubilizing agent, the sulfonate, is already in the solution. As one can surmize, the sulfonate acts as a dispersing and solubilizing agent for iodine as well as for the lower molecular weight amines. The higher molecular weight amines are oil-soluble, in which case, the sulfonate functions to solubilize only the iodine. Addition of more iodine and/or amine will require more sulfonate.

standard Falex testing machine using stainless steel V- blocks and brass test pins.

Table I shows results of Falex EP test of oils containing iodine on stainless steel test pins. In Table I, and subsequent tables, the acronym TEA represents triethanolamine; (W) indicates Welding of the test piece at the particular load and termination of the test; and (S) indicates shearing of the shear pin, meaning that the load carrying capacity of the lubricating composition is 10 higher than the recorded value. The load limit of the Table I shows that Blend 1, without any triethanolamine, lost substantially all of its load carrying capacity in three days. Blend 2, containing 0.25 weight percent 30 triethanolamine, retained its load carrying capacity even after standing for over two months. Blend 3 showed a load carrying capacity of 2500 pounds when tested on the day of blending, but lost substantially all of its load carrying capacity in ten days. Upon addition of 0.25

35 weight percent of triethanolamine on Oct. 5, 1966, to

Blend 3, which was prepared on Sept. 6, 1966, its load carrying capacity was synergistically restored to 3750 pounds, which is 1250 pounds above its original load carrying capacity. Blend 4 shows that with 0.25 weight 40 percent of iodine and 0.25 weight percent triethanolamine,

the load carrying capacity exceeds 4500 pounds, and this value was retained even after two months. In general, the results in Table I show that amine dramatically improves storage stability and enhances performance of 45 lubricating compositions containing iodine.

Another set of tests was conducted wherein the storage periods were further extended. The results are tabulated in Table II below.

TABLE II on s0. 0 s9. 65 39. 9 s9. 65 80. 75 $9. 5 Sultanate 5. 0 5. 0 5. 0 5. 0 5. 0 5. 0 5.0 5.0 5.0 5.0 5.0 5.0 0.1 0.1 0.1 0.1 0. 25 0. 25 0.25 0.25 0. 25

2,500 (W) 3,500 s 2,750 (W) 3,750 s 4,500 4, 250 s 750 (W) 000 (W) 3,000 (W) 4,500 250 (W) 5, 250 s 500 (W) 3,250 s 1 750 W 4, 250 s 3,250 s 3,500 e 1 000 W 4,000 s 12 weeks 500 W 4, 250 s A preliminary test was conducted to determine effec- Results in Table II confirm results obtained in previous tiveness of triethanolamine in iodine lubricants with re- 60 tests. Especially significant is the last column which shows spect to performance and storage stability.

A number of lubricating compositions were prepared in accordance with above-described procedure, with the exception that amount of iodine and the amine was varied,

as indicated in Table I below. The effectiveness of the 65 particular lubricating composition was determined on a that the lubricating composition comprising 0.25 weight percent of iodine and 0.25 weight percent triethanolamine retained its load carrying capacity even after twelve weeks.

Table III shows the effect of varying amount of certain additives on load carrying capacity of the lubricating compositions.

TABLE III Oil 89. 5 89. 65 89 74 80. 65 8). 4 89. 8 89. 89 89. 74 89. 98 79. 65 79. 5 79. 75 44. 75 34. 75 39. 75 89. 70 Sullonate 5. 0 5. 0 5 0 5. 0 5. 0 5. 0 5. 0 5. O 5. 0 15. 0 15. 0 15. 0 50.0 50.0 50.0 5. 5 Chlorinated wax 5. 0 5. 0 5 0 5. 0 5. 0 5. 0 5. 0 5, O 5. 0 5 0 Iodine 0. 25 0. 25 0. 25 0. 1 0. 1 0. 1 0. 1 0. O1 0. 01 0 25 0. 25 0 25 0. 25 0. 25 0. 25 EFiA O, 25 0 10 0.01 0. 25 0. 5 0. 1 0. 01 0. 25 0. 01 O 10 0. 25 10.0 5. 0 0. 25

a ex.

Fresh 4, 000 3, 750 3, 500 3, 000 3, 000 2, 500 1, 000 1, 000 250 3, 500 250 250 1, 750 2, 500 250 2 weeks- 3, 500 3, 250 3, 750 3, 000 2, 500 2, 0 750 500 2, 250 250 25 0 1, 500 2, 000 4 WeekS 3 0 2, 500 3, 250 2, 750 2, 750 1, 0 2, 250

Table III indicates that best results are obtained with zene, diaminotoluene, methylene aniline, methylene dilubricating compositions comprising a sulfonate, chloaniline, p-aminoazozenzene, o-aminoazotoluene, diethylrinated wax, and iodine and triethanolamine in an amount enediamine, amphetamine, a-naphthylamine, ,B-naphthylof 0.1 to 0.25 weight percent. amine, phenyl-a-naphthylamine, 1-cyclopentyl2-amino To determine effectiveness of triethanolamine on iodine- 5 propane, bis(1-ethyl-3-methylpentyl)amine, diphenylcontaining lubricants wherein iodine was in a form of amine, triphenylamine, octylamine, dodecylarnine, tetraiQdine compounds, tWO lu i t nds r prepar decylamine, hexadecylamine, octadecylamine, docosylu g Mallinckfodt Samples and The amine, coco amine, tallow amine, hydrogenated-tallow hhckl'odt Sample was eithfir an aliphatic heteroamine, cottonseed amine, didodecylamine, ditetradecyl- Cyclic Compound in which iodine Was non-aromatic- 10 amine, dihexadecylamine, dioctadecylamine, dicoco amine, linckrodt Sample contained aromatic iodine. In dihydrogenated-tallow amine, di(eicosyl-docosyl)amine, Sample iodine Content Was in the range of 50 to trioctylamine, tridodecylamine, tricoco amine, isooctyldi- 50 Weight Percent, While in Sample it Was 60 to coco amine, trihydrogenated-tallow amine, N-methyl di- 85 weight percent. This constitutes all available pertinent hydrogenated tanow amine, N,Ndimethyldodecylamine, information on these samples. The composition of these 15 N,N dimethyltetradecylamine, N,N dimethylhexadecyp Samples is fegafd ed P P Y f mijmufacmreramine, N,N dimethyloctadecylamine, N,N dimethyl T above hlbflcallng COmPOSIUOIIQ 113mg lodlne coco amine, N,N-dimethyl(octadecenyl octadecadienyl) pounds were tested on the Falex machine with the followamine, NyNdimethyl hydrogenatemtanow amine, fesultsdecenyltrimethylenediamine, N-coco triniethylenediamine, TABLE IV N-tallow trimethylenediamine, N-(octadecenyl-octadeca on 9M0 9375 99m 9M5 dienyl)trimethylenediamine, 2 -amino-1-butanol, 2-amino- Mallinckrodt #2 1.0 .0 Z-methyl-l-propanol, polymeric amines such as polyethylenimine, polyallylamine, etc. Sultanate 00 The above group of compounds represents an attempt 250 (W) H28 250 (W) 1 25 to list presently commercially available compounds use- 250 (W) 1, 750 (W) ful 1n the instant invention. It is, however, intended to 1,750 (W) 1, 750 W hveeks cover other related compounds, whether commercialized or not.

A number of other amines have been found to impart The useful compounds are classified into primary, secdesirable properties to the iodine-containing lubricants. 30 ondary, and tertiary amines; and aliphatic amines from Table V lists some of these amines and results of the about 1 to about 36 carbon atoms, aromatic amines from Falex tests conducted on lubricating oil samples having about 6 to about 24 carbon atoms, alicyclic amines from the indicated composition. about 3 to about 12 carbon atoms wherein the ring or TABLE V Oil 87.25 87.25 37.25 87 25 Sulfonate 50 Chlorinated Wax 00 00 o 'ne .25 .25

Triethanolamine Triisoprop melamine Tri-n-butylamine... Triethvlamine- Diethylamine.

Sec-butylamin n-Butylamine. Aniline.

N-ethylaniline Falex:

Fresh 4. 000 4, 500 4, 000 2, 500 4, 25 3,000 500 3, 500 4, 000 2 k 2, 750 4, 250 3, 000 2, 500 3, 500 2, 000 2, 750 2, 000 3,000 3, 000 3, 500 4 weeks 1, 000 4, 50 3, 000 2, 750 3, 250 2, 250 2, 500 2,000 2, 750 3, 250 3, 500

Examples of amines useful in the present invention for rings contain only carbon atoms, and polymeric amines.

enhancing lubricating properties of the iodine-containing Preferably, the amines are classifiable into alkylamines lubricants, and for imparting performance and storage from about 1 to about 15 carbon atoms, alkanolamines stability thereto, are the following: methylamine, difrom about 2 to about 12 carbon atoms, and aromatic methylamine, trimethylamine, chlorine, ethylamine, diamines from about 6 to about 18 carbon atoms. Aromaticethylamine, triethylamine, n-propylamine, isopropylamine, aliphatic amines are to be considered as aromatic amines. aminomethylpropanol, monoisopropanolamine, diisopro- Although a gamut of amine compounds have been dis pylamine, triisopropanolamine, butylamine, monoallylclosed as being useful in the iodine-containing lubricants, amine, amylamine, diamylflmihe, triamylamine, y it is intended to exclude related compounds such as amamine, heptylamille, monoethanolamihe, diethylethahol' monia, pyridine, picolines, quinolines, isoquinoline, quinamine, triethaholamihe, ethyl monoethaholamine, aminoaldine, indole, acridine, acridone, carbazoles, piperazines ethyl ethanolamine, aminoethylpropanol, benzyldimethyland the like amine, ethylene diamine, diethylene triainine, triethylene It is intended to limit the present invention only to tetramine tetraethylene Pentamine guamdme: dlphenyl' iodine-containing lubricants. Amount of an amine to be guanidine triphenylguanidine diorthotolyguallldme hexa' added to achieve storage and performance stability can methylenetetramin? aniline.fprmaldehydeiapllme conden' be experimentally ascertained by a man ordinarily skilled Satlon Products dmethyamlme ethyl amlme fl-phenyl' in the art. Amount of iodine to be added is well docuethylamine, diethylaniline, ethylidene aniline, ethylbenzylaniline, cyclohexylamine, dicyclohexylamine, cyclopropylamine, (cyclohexylmethyl) amine, dipherliylamine, oipherilaniline, o-amino henol, m-aminopheno p-aminop eno iiylidine, diethyl-o toluidine, o-phenylenediamine, p-phenof a llaftlcular luhfvlcant f ylenediamine, m-phenylenediamine, p-diaminodiphenyl, h e e above l yentlqn hasbeen described with a m-toluidine, p-toluidine, N-ethyl-o-toluidine, N-ethyl-mcerta n degree of particularity, it is realized that various toluidine, N-ethyl-m-toluidine, methyl diethyl aminobenadditional modifications and adaptations can be made mented in the herein noted prior art patents. Type and amounts of other additives for lubricants can be ascertained from prior art and will be dictated by requirements Within the spirit and scope of the invention as hereinafter References Cited gfs- UNITED STATES PATENTS 1. In a lubricant comprising a major proportion of 2,268,608 1/1942 McNl-llty et 252-515 X hydrocarbon oil of lubricating viscosity, elemental iodine 5 3384,409 1/1965 Furey X in a friction-reducing amount, a high molecular weight 3,220,949 11/1965 Bell et 252-515 petroleum sulfonate in an amount of about 1 to 10 weight 3,228,880 1/1966 Roberts et 252-51 percent chlorinated Wax in an amount of about 1 to 10 2,696,473 12/1954 sokol X Weight percent, and an amine in an amount of about 0.01 to 0.5 Weight percent, said amine is selected from DANIEL WYMAN Pnmary Exammer the group consisting of 10 W. CANNON, Assistant Examiner (a) alkylamines from about 5 to about 15 carbon atoms, U.S. Cl. X.R. (b) alkanolamines from about 2 to about 12 carbon 252 49 53 atoms, and 15 (c) aromatic amines from about 6 to about 18 carbon atoms.

Patent No. 99, 39 Dated M rch 10, 1970 Inventor (s) Julius Boehm It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1: Line 64, "by should be --of--;

Column 2: Line 31, "raneg" should. be --range--;

Column 4: Table III, last column, "89.70" should be "89.75";

"5.5" should be --5.0--;

Column 5: Table V, last column, "87.2 should be --87.25--;

Column 6: Line 2, "p-aminoazozenzene" should be --p-aminoazobenzene--;

Line 29, "classified should be --classifiable--.

Signed and sealed this 3rd day of August 1971.

(SEAL) Attett EIMARD M.FLETCHER,JR. WILLIAM E. SCHUYLER, JR. Attesting Officer Commissioner of Patents