US2606182A - Lubricating oil additive - Google Patents

Description

Patented Aug. 5, 1952 UNITED STATES PATENT OFFICE 2,606,182 LUBRICATING OIL ADDITIYE John M. Musselman, South Euclid, Ohio, assignor to The Standard Oil Company, Cleveland, Ohio,

a corporation of Ohio No Drawing. Application June '1, 1947,

. Serial No. 753,359

in an internal combustion engine operating at high temperatures and inwhich the lubricant is in close contact with metallic surfaces, metal compounds and high temperature gases. They are also suitable as extreme pressure lubricants in oils and greases.

The art appreciates that many diverse factors are involved in attaining a single lubricating oil addition agent which imparts to the oil little or no lacquer formation and also shows little or no deterioration or corrosion of metals, especially bearing metals with which the lubricant comes in contact, as well as low oxidative deterioration, as indicated by low viscosity increase, sludge, etc. It is very difiicult to produce a single addi tion agent which is nearly optimum for all these factors, especially at a commercially interesting cost.

In accordance with the invention, it has been found that a reaction product may be obtained by reacting together an unsaturated hydrocarbon, an oxygen-containing organic compound and a phosphorus sulfide; and this reaction product is an excellent lubricant or additive for lubricants. These reaction products have good solubility in oils and greases, and improve the corrosion, lacquer, sludge, viscosity increase, and

the like characteristics thereof. They also improve the extreme pressure lubricating characteristics of oils and greases. Derivatives obtained from these reaction products, e. g., metal derivatives, nitrogen basederivativ'es, ester derivatives, or mixtures, or mixed derivatives thereof also have these desired properties. These products have improved corrosioncharacteristics as compared with the phosphorus sulfide-organic oxygen compound type additives, and also do not have the poor lacquer characteristics of the phosphorus sulfide-olefin type additives.

The reaction products of the invention are to be distinguished from a mixture of the sulfideclefin reaction product and the sulfide-organic oxygen-containing compound reaction product, and are superior to such a mixture. This suggests that the reaction product of the invention is not simplya mixture of the two types of reaction products, but rather that there is some interaction giving an unexpectedly superior prod uct.

cent is especially, desirable.

2 The objects achieved in accordance with the invention include the provision of an agent which may be useful itself as a lubricant, and which when added to lubricants will markedly inhibit the very objectionable deposition-of lacquer, and,

at the sametime, inhibit acid and sludge formation, cor'rosionand other types of deterioration occurring under operating conditions; the provision of lubricating oils containing such an addition agent; and other objects which will be apparent as embodiments of the invention are disclosed hereinafter.

The reaction product may be made with direct admixture of the reactants, or, if desired, by

their admixture inthe presence of a diluent which may or may not be subsequently removed. A heavy oil such as white oil, or a lubricating oil having about the same properties as that to which the new composition is to be added may be used as a diluent. The reaction is usually complete in about 10 hours or less time, generally 1 to 2 hours. The reaction time is a function of the temperature, the amount of the sulfide that is to react, the subdivision of the reactants, the

efficiency of mixing, etc.

The mixture of unsaturated hydrocarbon and oxygen-containing organic compound may be reacted with the phosphorus sulfide or a mixture of phosphorus sulfides in ratios from 5 to about .60 weight percent of the phosphorus sulfide based on the weight of the above mixture. Generally about to about 50 percent is the usual range that will be used, depending on the molecular weight of the unsaturated hydrocarbon and its proportions relative to the oxygen-containing organic compound, and about to about per- Small amounts show a significant improvement, and economic factors may make it undesirable to use more than is necessary to achieve the desired improvement.

Phosphoruspentasulfide is preferred although other phosphorussulfides or mixtures of sulfides may be employed. Phosphoruspentasulfide is most economic and readily available and for this reason is used in the illustrative examples.

In general, unsaturated hydrocarbons having atleast about 4- to 6 carbon atoms in the molecule are suitable. The unsaturated hydrocarbon may contain one or more pairs of double or triple bonded carbon atoms. Olefihs are preferred including the high molecular weight olefin polymers. These olefin polymers may be prepared by the polymerization oflow molecular weight olefins, as is known to the art; Their molecular weight generally ranges above 1 and such polymers are known which have a moleculagagsaight in the rangeof about 3,000 to about 5 The advantages of the invention are particularly apparent in the case-of products obtained from unsaturated hydrocarbons having from about 6 to about carbon atoms in the molecule. A commercially desirable olefin is socalled motor polymer or reduced motor polymer. C3 and C4 olefins by non-selective polymerization, e. g., with a phosphorus acid type catalyst. to 500 F., with a major portion boiling in the range of 120 to 400 F.

A polymer gasoline fraction may be removed Motor polymer is usually made from Motor polymer boils in the range of 80 therefrom by fractional distillation to the 250 F. cut point, and this reduced form motor polymer'is particularly useful. The reduced motor polymer may contain small amounts of materials lighter thanthe trimer. Its average molecular weight is'about 145 and it preferably contains amajor amount of branched chain olefins boiling below .600 F. The unsaturated hydrocarbon used should be selected, e. g., of a suitable molecular weight, to give a final product having the desired oil solubility or dispersibility. It is preferred to employ unsaturated .compounds which are soluble or dispersible in lubricating oil. Polyolefins may ;be used, but conjugated polyolefins giving an undue amount of sludge would not be preferred.

The oxygen-containing organic compound may contain hydroxy, carbonyl, or ether oxygen; and is desirably of rather high molecular weight; preferably boiling above the reaction temperature; the reaction may be conducted under pres sure, if desired, in the case of lower boiling materials. Theremay be used ester waxes, as lanolin, degras, sperm oil; esters, as alkyl or cycloparaflin or aryl esters of organic acids; fatty oils, higher alcohols, higher carboxylic acids, saturated and unsaturated, monobasic and dibasic, petroleum acids, naphthenic acid, rosin, modified rosin, glycol ethers, higher ketones and aldehydes; also halogenated derivatives of any of these. Illustrative of some conveniently applicable materials are: beeswax, lanolin, sperm oil, other waxes, butyl stearate, ethyl lactate, methyl oleate, butyl ricinoleate, butyl phthalate, methyl stearate, methyl dichlorostearate, methyl chloronaphthenate, dichloropalmitic, acid, cocoanut oil, babassu oil, hydrogenated cocoanut and other vegetable oils, other fatty oils, ethylene glycol mono ethers, diglycol chlorohydrin, lauryl alcohol, stearic acid, lauric acid, oleic acid, palmitic acid, myristic acid, naphthalic acid, naphthoic acid, benzoic acid, naphthenic acids, hydroxystearic acid, dihydroxybenzoic acids, hydroxynaphthenic acids, dihydroxystearic acid, chlorobenzoic acid, dichlorostearic acids, dichlorobenzoic acid, dichlorodihydroxystearic acid, lactones, palmitone, oxidized petroleum fatty acid or other petroleum product, as oxidized wax, kerosene, gas oil or other oxidized petroleum oil. The oxygenated compound used in forming the reaction product should be selected with reference to the use of the final composition and the properties desired in it, e. g., to give a reaction product having oil solubility or dispersibility.

The relative amounts of the unsaturated hydrocarbon and the oxygenated organic compound are not critical. Widely different proportions show significant improvement. Substantially equal weight ratios of the hydrocarbon and the oxygenated compound are suitable and proportions in the range of 10 to 70 partsof the oxygenated compound to 90 to parts of the unsaturated hydrocarbon are preferred.

The reaction may be carried out in the presence or absence of air, or in the atmosphere of inert or nondeleterious 'gas, such as nitrogen or H25. It may also be carried out under pressure, e. g., the pressure generated when the reaction is carried out in a closed vessel.

A reaction temperature varies with unsaturated compound and oxygen-containing compound and, is readily ascertained. The optimum is in the range of 200 to 500 F., although a higher temperature which is below that at which the reaction product would be decomposed could be used. A temperature of at least 250 to 300 F. is preferred in many cases.

The final reaction mass is preferably centrifuged or filtered to remove the-by-product sludge, or other insoluble material. Any excess of a volatile reactant, or a volatile diluent, may be removed by distillation. If desired, the final product may be solvent extracted with a suitable solvent, e. g., liquid propane or isopropyl alcohol, or contacted with an adsorbent such as activated charcoal, silica gel, activated clay, and the like.

An element of the sulfur family, i. e., sulfur, selenium or tellurium, can be incorporated into the reaction product. This sulfur can be incorporated by adding elemental sulfur or a compound which yields sulfur, such as by treating the sulfide-derived reaction product therewith, or treating a derivative of the sulfide-derived reaction product therewith.

If additional reacted sulfur is to be present in the additive, about 0.01 to 2.0 and preferably 0.1 to 1.0 gram atoms of sulfur per mol of the phosphorus sulfide used, is incorporated by adding elemental sulfur, e. g., simultaneously with, or after the formation and cooling of the primary reaction product; if after, the mass is maintained at about 200 to 300 F. for about a few minutes to several hours, and preferably about one hour. Selenium'and tellurium function in much the same Way as sulfur in this respect, and may be incorporated similarly. Alternatively, the sulfur can be added to the metal, nitrogen base, or ester derivatives.

The sulfide, derived reaction products including those containing an added sulfur family element may be utilized in the form of their metal, nitrogen base or ester derivatives. Mixed derivatives or mixtures of the derivatives may be employed. These derivatives are formed from agents capable of replacingan acid hydrogen atom. Although the formation of the above derivatives may not involve replacement of acid hydrogen, the materials used as agents fall into the class of materials capable of replacing or reacting with acid hydrogen.

The metal derivatives may be formed from one or more metal compounds, such as their sulfides, oxides, hydroxides, carbides and cyanamides. The preferred metals are group I, group II and group III metals ofthe periodic table, such as potassium, zinc, barium and aluminum. For particular services, the heavier metals have particular use, i. e., those below zinc in the electromotive series, such as chromium, cadmium, tin, lead, antimony, bismuth, arsenic, and the like. Y

The metal additive compounds, especially those fully saponified so as to have a high metal content, may be mixed with oils to .form greases, with or without conventional soaps, and in such cases the metal additive compounds serve. to

thicken the oil as well as to "stabilize it and impart a detergent action.

When a metal, nitrogen base, or ester derivative containing subsequently added reacted sulfur is desired, there are two primary alternative ways of producing it: (1) the sulfide-derived reaction product can be reacted with an element of the sulfur family and this reaction product then converted into thederivative, or (2) the primary sulfide-derived reaction product can be converted into the derivative and this derivative then'reacted with an element of the'sulfur family.

In the preparation of the above type metal derivatives, the reaction step of forming the metal derivatives may be carried out at temperatures in the range of about 100 to about 350 F., a temperature in the range of about 180 to 250 F. being preferred.

From about 0.25 to about 6.0 equivalents of the metal compound may be used for mol'of the sulfide used in the sulfidederived reaction product, preferably about 1.0 to about 3.0 equivalents. An equivalent is the quotient of amol divided by the valence of the metal concerned.

The sulfide-derived reaction products may "be converted to their nitrogen base derivatives by reaction with one or more basic nitrogenous compounds, such as ammonia, amines, or heterocyclic nitrogen bases. Generally, ammonia and the gaseous or liquid amines or nitrogenous organic compounds are preferred. Analogous polyamines may be used similarly.

From about 0.25 to about 6.0 equivalents of the nitrogen base may be usedper mol of the sulfide in the sulfide-derived reaction product, preferably about 1 to about 4 equivalents. An equivalent is the quotient valenceof the nitrogen base concerned.

of a mol divided by the The ester derivatives may be prepared reaction of the sulfide-derived reaction products 'with one or more alcohols, or thio-alcohols, or alkyl, aryl, cycloalkyl,

and heterocyclic compounds containing an alcoholic or thio-alcoholic group. The term ester derivative is used in its generic sense to include any .oith'e above types of compounds. I

The reaction of forming the ester derivatives may be-carried out at temperatures in about the range of 100 to 350 F., a temperature of 180 to 280 F. beingpreferred. Fromabout 0.2 to about 6.0 equivalents of the esterifying agent may be used per mol of the sulfide in the sulfide-derived reaction product, preferably about 1.0 to about 4.0 equivalents. An equivalentis the quotient of a mol divided by the valence (e. g., number of alcoholic or thiolgroups in the molecule) of the agent used.

It is beneficial to have water present in the reaction step of forming the metal or the nitrogen base derivative, and this may be introduced as water of crystallization, or as a hydrate of the metal compound or'of the nitrogen base, or it may be introduced separately.

A plurality of metals or of nitrogen bases, or of esterifying agents, or mixtures of any two-or more thereof, may be used.

If the amount of the metal, nitrogen base or alcohol or combinations thereof, is small, the final product may be a mixture of the initial reaction product and the metal, nitrogen base or ester derivative.

The yields in the above reaction steps are very high. v

' The amountoi the final-reaction product (i. e., the additive) to be incorporated in an oil or 0 grease will depend upon the charact'eristics of the oil orgrease and the intended-use. Some oils have more of a tendency to corrode me'tals,

or to'form acids, sludges andla'cquer deposits than others, and such oils require larger quantities of the addition agent. Also, oils that are intended for higher temperatures require larger amounts of the additive. In general, the range is from about '1 toabout- 10%; under some circumstances, amoun't'sas low as-about 0.01% show a significant improvement. since the secondary reaction product is a lubricant, there is no upper limit. However, it maybe uneconomical to include in the lubricant more of the se'condary reaction product than is necessary to" impart the desired properties, such as 50%.

The following working examples illustrate the scope of the invention:

A GQNVENTIONAL'PETROLEUM BASE LUBRICATING. 01L

CONTAINING '1 TO 10% on ANY ONE or THE For.- LOWING COMPOSITIONS (ALL PARTS 0R PERCENTAGES A-RE BY WEIGHT UNLESS OTHERWISE INDICATED HEREIN 1 1. Reaction product of 1 to 3 parts of cycle-- hexanol, 1 to 3 parts of reduced motor polymer, and 1 to 5 parts of P2S5 reacted together at'a temperature in the range of 200 to 500 'F.

2. Reaction product of 1110 3 parts of a glycerol stearate, 1 to '3 parts ofcetenel, and l-to '5 parts of PzSs reacted-together at a temperature in the range of 200 to 500F.

3. Reaction product ofi to 3-parts iof degras, 1 to 3 parts of octene-Z, and 1 to 5 parts of P285 reacted together at a temperature in the range of 200 to 500 F. r r

4. Reaction productof "1 'to 3 parts of cetyl-alcohol, 1 to 3 parts of penta-decene-Biand.l to 5 parts of P235 reacted together at a temperature in the range of 200 to 500 F.

.Re'action product of 1 to 3 parts of coconut oil, 1 to 3 parts of motor polymer, and 1'to 5 parts of P487 reacted together a't-a temperature in the range of 200? to 500F.

6. Reaction product of 1 to 3 parts of natural beeswax,i1 to 3 parts of reduced motor polymer,

and 1 to 5 parts of 'P'zssreactedtogether at a temperature in the range of 200 to 500 F.

'7'. Reaction product of 1 to3 parts of palmitonje, 1 to 3 parts of highly cracked hydrocarbon stock, and 1 to 5 parts of PzSs reacted together at a temperature in the rangeaof to 500 F.

8. Reaction product'of 1 to 3 parts of sperm oil,

1 to 3 parts of a mixture of C6 to C12 monoolefins, and 1 to 5 parts of P zss reacted together at a ten'iperature in the range of .200?- to 500 F. 1

9. Reaction product of 1 to -.3 -parts of diamyl phenol, 1 to 3 parts of motor lpolymenand 1 to 5 parts of P285 reacted together at a temperature in the range of 200to400" F.

10. Reaction product of Ito-3 parts of amixture of stearic and oleic acid, .1 to 3 parts of a mixture of C8 to C1 mono-olefins, 1 to 5 parts of P285 reacted together at a temperature in the range of 200 to 500F.

11. Reaction product of- 1 to '3- partsv of methyl stearate, 1 to 3*p'arts of highly-cracked'hydrm carbon stock,'and 1 5 partsof-PQS5 reacted together at a temperature'in the range of"100 12. Reaction product of 1 to 3 parts of cyclohexanone. 1 to 3 parts of a mixture *of' G6 to GL2 V mono-olefins, andl "to-"5 pa rtsgof Pzs sreacted together at "a temperature in the range lof" 200 to 500 F.

Example A 38 parts of P285 is mixed with 100 parts of reduced motor polymer and agitated for 8 hours at 350 F. in a pressure reaction vessel, at a pressure of about 100 pounds per square inch. Some gas is vented during the reaction, depending upon the free space in the vessel, in order to maintain this pressure. A 100% yield is obtained, based on the motor polymer, and no sludge is formed, but it is preferred to filter the reaction product. The product analyses 23.0% P, and 7.0% S; and is referred to as additive A hereinafter.

' Example B Hydrogenated sperm oil is available under the trade name of Spermofol No. 52. It has an iodine value of 6-7, a melting point of 50-52 C., a free fatty acid content (as oleic) of 1.0-2.0%, a saponification value of 135-138, and about 36% of unsaponifiables.

This hydrogenated sperm oil is reacted with 32% by weight of phosphorus sulfide at a temperature of about 300 F. After the reaction is complete, which, under reaction conditions, takes one hour, the material is permitted to stand, after which the by-product residue settles and the reaction product is decanted; following this, it is filtered with the use of a filter aid. An 80% yield is obtained of the product; which analyses 2% P and 14% S; and this is referred to as additive B hereinafter.

Example I (a) Following the'procedure of Example A, 32 parts of phosphorus pentasulfide is reacted at 300 F. with a mixture of 50 parts of reduced motor polymer and 50 parts of the above described hydrogenated sperm oil. An 86% yield of the product is obtained, after filtration to remove sludge, and it analyzes 5.57% P and 16.32% S; this is referred to as additive 1(a) hereinafter.

Example I (b) A reaction product prepared in accordance with the above procedure 1(a) is mixed with 11% by weight of potassium hydroxide and 15% by weight of water, and the mixture heated with agitation at 300 F. for 30 minutes. The reaction mass is then blown with air while maintained at about 200 F. for 1% hours. It is then filtered hot. The filtered product analyzes 20.49% ash (as sulfate), 5.32% P-and 14.57% S; and is referred to hereinafter as additive I(b).

Example 1(0) A reaction product prepared in accordance with the above procedure I(a) is mixed with 20% by weight of barium hydroxide octahydrate and heated with agitation at 180 F. for 4 hours, and then at 250 F. for 1 hour. The reaction mass is then blown with air while maintainedat 200 F. for l hours. It is then filtered hot. The filtrate product analyzes. 11.4% ash and 12.92% S and is' referred to hereinafter'as additiveI(c).

8 Examplev II (a) Following the procedure of Example 1(a), except using 25 parts of phosphorus pentasulfide, a reaction product is prepared. A 96% yield of a product is obtained, after filtration to remove sludge; it analyzes,3.68% P, and 13.78% S, and is referred to as additive II(a) hereinafter.

Example II (b) Following the procedure of Example 1(a), except using 40 parts phosphorus pentasulfide, a reaction product is prepared. An 85% yield of of a product is obtained, after filtration to remove sludge; it analyzes 5.8% P and 20.47% S, and is referred to as additive II(b) hereinafter.

Example III Following the procedure of Example 1(a), 34.75 parts of phosphorus pentasulfide is reacted with a mixture of parts of reduced motor polymer and 25 parts of the hydrogenated sperm oil. A 93.43% yield of the product is obtained, after filtration to remove sludge; it analyzes 6.72% P, and 18.14% S; and is referred to as additive III hereinafter.

Example IV Following the procedure of Example 1(a), 28.75 parts of phosphorus pentasulfide is reacted with a mixture of 25 parts of reduced motor polymer and 75 parts of the hydrogenated sperm oil. An 86% yield of the product is obtained, after filtration to remove sludge; it analyzes 3.61% P, and 15.05% S, and is referred to as additive IV hereinafter.

Example V Following the procedure of Example 1(a), 32 parts of phosphorus pentasulfide is reacted at 250 F. with a mixture of 50 parts of reduced motor polymer and 50 parts of the above described hydrogenated sperm oil. An 82.5% yield of the product is obtained, after filtration to remove sludge; it analyzes 6.64% P, and 16.46% S, and is referred to as additive V hereinafter.

Example VI Following the procedure of Example 1(a), 32

parts of phosphorus pentasulfide is reacted at 350 F. with a mixture of 50 parts of reduced motor polymer and 50 parts of the above described hydrogenated sperm oil. An 87.27% yield of the product is obtained, after filtration to remove sludge; it analyzes 4.4% P, and 17.15% S, and is referred to as additive VI hereinafter.

Example VII Following the procedure of Example 1(a), 42 parts of phosphorus pentasulfide is reacted at 300 F. with a mixture of 50 parts of reduced motor polymer and 50 parts of stearic acid. The product is filtered to remove sludge, and it is referred to as additive VII hereinafter.

Example VIII parts of phosphorus pentasulfide is reacted at 300 F. with amixtureof 50 partsofreduced motor polymer and 50 parts of. lauryl alcohol;

and the product is referred to as additive IX hereinafter. 7

xample. X

Following the procedure of Example VII, 38 parts of phosphorus pentasulfide is reacted at 300 F. with a mixture of 50 parts of reduced motor polymer and 50 parts of n-octyl alcohol,

and the product is referred to as additive X hereinafter.

Example. XI

Example XII.

Following the procedure of Example VII, 32 parts of phosphorus pentasulfide is reacted at 300 F. with a mixture of 50 parts of reduced motor polymer and 50 parts of an oxidation product, obtained by the controlled oxidation of a fraction of Pennsylvania petroleum, of Sp. gr. at 158 F. 08654-08448 Viscosity, Saybolt sec. 1 40-49 Melting point, F. 94-100 10- called degras. The product is filtered to remove sludge, and is referred to as additive XV hereinafter.

In testing the oils containing addition agents, an ethyl motor is used, under the following conditions:

Procedurenrfil 1 II Type engine Series ethyl Engine speed 1200 R. P. M. Sump temp 300 F. Jacket temp 212 F. Air fuel ratio 12-515 to 1 Compression 7 to 1 Catalyst None For comparative purposes, the test values for piston skirt, acid number, pentane insolubles, and 1/100 the viscosity increase maybe added; the sum is multiplied by 10, and divided by the number of hours the test is run. The resulting value is termed the demerit rating.

A conventional solvent extracted lubricating oil base stock SAE 30) and blended compositions of this oil made in accordance with the invention were submitted to tests in accordance with the described ethyl motor procedure. The results in the following Tables A, B and C are typical.

TABLE A (50-hour 80-hour IOU-hour Additive of Example No. and O A 1 v h n 0.5%A 1.0% 0.5%A 1.0% narrates.rarer. m 0 w 1 0 m a Piston Skirt Rating..." 2.5 0.5 4.0 1.0 5.0 2.5 Viscosity Increase (SUS) 131 59 155 61 167 63 Acid Number 0.875 0.75 0.875 1.0 1.0 1. 25 Ientane Insolubles (in percent by weig 1.0 0. 2 1.0 0. 4 1.8 0.5 Dernerit Rating 0.93 0.35 0. 94. 0.38 0.95 0.49 Corrosion of Cu-Pb bearing metal (in mgms. weight lcs per bearinghalf-she11) 1 286 85.0

Flash point F. 280-300 The oil alone only ran 20 hours, and showed a Acid No, 8-12 demerit, rating of 6.7. Saponification No 100-140 This Ialole A data shows the marked supe- (and available commercially as Alex 152).

The reaction product is filtered to remove sludge;

and is referred to as additive XII hereinafter.

Example XIII Following the procedure of Example VII, 32 parts of phosphorus pentasulfide is reacted at 300 F. with a mixture of parts of reduced motor polymer and 50 parts of commercial diamylphenol; and the product is referred to as additive XIII hereinafter.

Exagnple XIV Example XV Following the procedure of Example VII, 33 parts of phosphorus pentasulfide is reacted at 300 F. with a mixture of 50 parts of reduced motor polymer and 50 parts of the crude grease obtained by washing sheeps wool, sometimes riority of solvent extracted base lubricating oil containing-the additive 1(a) of the invention, as compared to the same 011 containing about the same total amount of the separately reacted materials A and B (the latter may be regarded as the sum of the effects of the two added agents). The more than 3-fold improvement in corrosion together with the about 2-fold improvement in demerit rating is. especially noteworthy. I

In addition, it may be stated that the oil containing 1% of additive A alone showed a piston skirt rating of 5 .0 at 60 hours (i. e., lacquer characteristic poorer) and the oil containing 1% of additive B, alone showed a corrosion of 507. at hours (i. e. corrosion characteristic poorer).

TABLE B. -11 15) The above data show that the metal derivative additives I(b) and 1(0) are advantageous, especially as to piston skirt rating. The additives 11 prepared from a different ratio of P285, II(a) (25% P285) and 11(2)) (40% P2S5) also are advantageous; the latter shows the better piston skirt rating of the two.

TABLE (100-hours) 1% by Weight of Additive of Example N0 I (a) III IV V VI Piston Skirt Rating 2. 2. 5 2 5 3.0 2. 5 Viscosity Increase (SUS) 63 91 65 52 147 Acid Number 1. 1. 75 1.25 1. 0 1.0 Pentane Insolubles (in percent by weight) 0.5 0.7 0. 4 0.75 0. 5 Demerit Rating 0.49 0. 60 0. 48 0.63 0.55 Corrosion of Ou-Pb bearing metal (in mgms. weight loss per bearing half-shell) 90. 3 44. 0 312 90. 0

The above data show that additives prepared from unequal weight ratios of unsaturated hydrocarbon to oxygenated-compound also are advantageous; the additive IV (from 3 to 1 mixture of the hydrogenated sperm oil to the reduced motor polymer) shows especially low corrosion. The additives prepared at different preferred reaction temperatures are advantageous. The additive 1(a) (prepared at 300 F.) and the additive VI (prepared at 350 F.) are more advantageous than that prepared at 250 F. (i. e., V). This data indicates that a reaction temperature of at least about 275 F. (or a subsequent heating of the reaction product to such a temperature) is to be preferred where the more advantageous product is desired.

The Sohio corrosion test was used in evaluating other blends made in accordance with the invention. This test is described in a co-pending application of E. C. Hughes, J. D. Bartleson, M. S. Sunday and M. M. Fink, which also correlates the results of the laboratory tests with a Chevrolet engine test.

Essentially the laboratory test equipment consists of a vertical thermostatically heated glass test tube (45 mm. outside diameter and 42 cm. long) into which is placed the corrosion test unit. An air inlet is provided for admitting air into the lower end of the corrosion unit in such a way that in rising the air will cause the oil and suspended material therein to circulate into the corrosion unit. The tube is filled with an amount of the oil to be tested which is at least sufilcient to submerge the metals being tested.

The corrosion test unit essentially consists in a circular relatively fine grained copper-lead test piece of lg" O. D., which has a 4 diameter hole in its center (i. e., shaped like an ordinary washer). The test piece has an exposed copperlead surface of 3.00 sq. cm. Of this surface area, 1.85 sq. cm. acts as a loaded bearing, and is contacted by a part of the cylindrical surface of a hardened steel drill rod 4" diameter and l" long, and of 51-57 Rockwell hardness).

The drill rod is held in a special holder, and the holder is rotated so that the surface of the drill rod which contacts the bearing sweeps the bearing surface (the drill rod is not rotated on its own axis and the surface of the drill rod which contacts the bearing is not changed).

The corrosion test unit means for holding the bearing and the drill rod is a steel tubing (15" long and 15 O. D.) which is attached to a support. A steel cup (1" long, 13%" 0. D. by l? I. D.) is threaded into the steel tube, at the lower end. The cup has a diameter hole in the bottom for admitting the oil into the corrosion chamber. The copper-lead test piece fits snugly into the steel cup and the hole in the test piece fits over the hole in the steel cup. A section of steel rod in diameter and 19 long) serves as a shaft and is positioned by 2 bearings which are fixedly set in the'outer steel tubing, one near the top and one near the lower (threaded) end thereof. Several holes are drilled just above and just below the lower hearing. The holesabove the bearing facilitate cleaning the apparatus, while the holes below the bearing enable the circulation of oil through the corrosion chamber. The drill rod holder is connected to the shaft by a self-aligning yoke and pin coupling. This assures instantaneous and continuous alignment of the drill rod bearing member against the bearing surface at all times. A pulley is fitted to the top of the steel shaft and the shaft is connected therethrough to a power source. The shaft is rotated at about 6'75 R; P. M. and the weight of the shaft and attached members is about 600 grams, which is the gravitational force which represents the thrust on the bearing. The air lift from the air inlet pumps the oil through the chamber containing the test piece and out through the holes in the steel tubing.

The ratios of surface active metals to the volume of oil in an internal combustion test engine are nearly quantitatively duplicated in the test equipment. The temperature used is approximately that of the bearing surface. The rate of air flow per volume of oil is adjusted to the same as the average for a. test engine in operation. Of the catalytic effects, those due to soluble iron are the most important. They are empirically duplicated by the addition of a soluble iron salt. Those due to lead-bromide are duplicated by its addition.

The test was correlated with a slightly modified version of the L-4 Chevrolet test. This modification comprised reducing the oil additions from the 4 quarts in the usual procedure to 2 quarts, by reducing the usual 1 pint oil additions which are made at 4 hour intervals to pint additions. This modification increases the severity of the test in its corrosion and detergency components, particularly in the case of border line oils.

For each test, the glass parts are cleaned by the usual chromic acid method, rinsed and dried. The metal parts are washed with chloroform and carbon disulfide and polished with No. 925 emery cloth or steel wool. A new copper-lead test piece is used for every test. The test piece is polished before use, on a surface grinder to give it a smooth finish. The test piece is weighed before and after the test on an analytical balance t evaluate the corrosion. After placing the oil and corrosion test unit in the tube, and bringing the assembly up to temperature in the thermostat, soluble catalyst is added and the air flow is started. Lead bromide catalyst is added immediately after starting the air, and timing of the test is begun.

The laboratory test conditions which were found to correlate with the modified Chevrolet procedure 36-hour test are the following:

At the close of the test period, the extent of corrosion is determined by reweighing the corrosion test piece and determining the change in weight due to the test.

A sufficient volume of used oil is obtained from the test for determination of the usual used oil properties, such as pentane insolubles, viscosity increase, and neutralization number.

The data in the followin tables typify the results obtained in 10-hour Sohio corrosion tests on conventional solvent extracted Mid-Continent lubricating oil base stock (SAE 30) and blends thereof compounded in accordance with the invention.

Additive of Example No None VII VIII IX. X XI Concentration of Additive in Percent by Weight (of I oil) 1.0 1.0 1.0 L 1.0 Corrosion of Cu-Pb mgms. weight loss of)- 3. 1 3; 9 5.0 13.4 8. 4 3. 2 Viscosity Increase (SUE). 426 88 146 410 131 162 Pentane Insolubles (in pe cent by weight) 0. 54 0.06 0. 78' 0.65 0. 60 0'; 28 Acid Number 3. 3 0. 93 0. 54 2. 40 0. 78 1.35

TABLE E Additive of Example No None XII XIII XIV XV Concentration of Additive in Percent by Weight (of oil) 0 1.0 1.0 1.0 1.0 Corrosion Cu-Pb (in milligrams weight loss of) 23.1 2. 9 .3 4. 3 2. 3 Viscosity Increase (SUS) 426 175 92 80 108 Weight Percent Pentane Insolubles (in percent by weight) 0. 54 1. 81 0. 08 0.63 0. 34 Acid Number 3. 3 0. 98 1.30 0. 54 0. 90

pentasulfide with degras, or with polybutene 0 polymer, or with mixtures of degras and polybutene polymer, at 300 F. for two hours, using proportions of reactants and obtaining products which analyze as follows:

Example No "1 Parts of Beactants:

Dcgras 100 Polybutene of 780 molecular weight 100 Polybutene of 940 molecular weight i 36 P235 Product Analysis:

' Per Cent P 1 Per Cent S X Example No XVI XIX XVII XVIII Parts of Reactants:

Degras Polybutene of 780 molecular weight Polybutene of 940 molecular weight Piss Product Analysis.

Per Cent P Per Cent S Example No XX XXI XXII XXIII Parts of reactants: A

Degras "-1 50 50 25 25 Polybutene of7780 molecular weight 50 50 75 75 28L 15 25 20 Product Analys Percent 1. 61 3. 5 2. 52. 4. Percent. S 7. 41 12. 9 7. 72 14 Example No XXIV XXV XXVI XXVII Parts ofReactants:

Degras 50 50 25 25 Polybutene of 940 molecular weight 50 50 75 75 Pass 2O 25 20 25 Product Analysis:

Percent P 2. 6 2.84 2. 7 3. 41 Percent S 10. 12. 80 10. 9 12.0

procedure. The results given in the following Tables F, G, H and I are typical.

TABLE I (GO-HOURS) Additive of Example No. and

Concentration thereof in 2%, 3 Percent by Weight Piston Skirt Rating 7. 0 1. 5 a. 0 1. 0

Viscosity Increase (S 276 110 211 106 Demerit Rating- 3.13 0. 72 2. 48, O. 58

Corrosion of Cu bearing mctaldn mgms. wt. loss per hearinghali-shell) 104. 1 70. 0 96. 0 62. 5

The blank oil (without additive) had a demerit rating of 18.56.

TABLE G (GO-HOURS) Additive of Example No. and 1 Concentration thereof in per- 3% 055% 3% cent by Weight 1.5% F XVIII 2.25% F XIX Piston Skirt Rating 4. 0 1. 5 4. 0 1.0

Viscosity Increase (SUS) 143 253 Acid Number 1.75 1. 25 2. 5 1. 00'

Pentane Insolubles (111 percent by weight) 1. 5 O. 35 3. 5 0. 30

Demerit Rating l. 45 0. 68 2. l 0. 5G

Corrosion oi Cu-Pb bearing metal (in mgms. wt. loss per bearing hall-Shell) 143. 2 64. 0 14-5. 2 78. 3

These Tables F and G data also show the marked superiority of acid treated base lubricating oil containing the additives of the invention, as compared to the same oil containing about the same total amount of the separately reacted materials C and one of D, E or F (the latter mixtures may beregarded as the sum of the separate effects of the two added agents). In. each combination, 1. e., XVI compared to C+D in corresponding proportions, XVII compared to C-l-E in corresponding proportions, XVIII compared to 6+5 in corresponding proportions, and XIX compared to C-I-F in corresponding proportions, both corrosion and demerit rating are greatly improved.

TABLE H (60 HOURS) 3% by Weight of Additive of Example N o XX XXI XXII XXIII Piston Skirt Rating 3. 5 2.0 2.0 3.0 Viscosity Increase (SUS) 64 110 54 97 Acid Number l. 50 1.75 2.0 2.0 Pentane Insolubles (in percent by Weight) 0.80 2.0 0. 80 4. Demerit Rating 1. 07 1. 0. 8S 1. 67 Corrosion of Cu-Pb bearing metal (in mgms. wt. loss per bearing hall-shell) 216 216 81. 3 192. 4

These Table H data show that additives of the type of the above discussed XVI and XVII, but made with different proportions of phosphorus pentasulfide, are advantageous.

TABLE I (60-HOURS) These Table I data show that additives of the type of the above discussed XVII and XIX, but made with different proportions of phosphorus pentasulfide, are advantageous.

Example XXVIII Following the procedure of Example XVI, an additive is prepared by reacting a mixture of 50 parts of reduced motor polymer and 50 parts of degras with 44 parts of P285. An 89.69% yield of the product is obtained.

To illustrate the value of the products of the invention as additives for extreme pressure lubricants, an SAE 90 gear oil blend, consisting of 55 parts of a Mid-Continent acid treated lubricating oil base stock (#300 red oil) and 40 parts by weight of Mid-Continent bright stock (#1), and compounded blends thereof containing 5% by weight of an additive were submitted to the standard Timken extreme pressure test. The following results are typical.

TABLE I 800 R. P. M. E. P. Lubricant Timken Test Oil alone l5# Oil plus 5% A 251; Oil plus 5% C 30# Oil plus 2.5% A, 2.5% C 2t# Oil plus 5% XXVIII 50?? These Table J data show the marked superiority of gear oil containing a typical additive of the invention XXVIII, as compared to the same oil containing about the same total amount of the separately reacted materials A and C (the latter mixture may be regarded as the sum of the separate effects of the two added agents), and also as compared to the same amount .of either A or C. The compounded blend of the invention shows a more than 3-fold improvement. over the oil blend alone. s

The above working examples and specific embodiments are for illustrative purposes only, and are not intended as limitations of the invention. In View of the foregoing disclosures, the art will clearly understand the invention in its broad aspects, including variations and modifications thereof.

If desired, the additives of the invention may be used together with other oil addition agents, e. g.,"pour point depressants or film strength agents. In some instances, it is desirable to include in a lubricating oil containing the additive an agent for improving the clarity of the oil, e. g., lecithin, lauryl alcohol, and the like, which are known to the art. In order to prevent foaming of the oil containing a small proportion of the additive, it is desirable in some cases to add a very small amount of tetra-amyl silicate, an alkyl ortho carbonate, ortho formate or ortho acetate, or a polyalkylsilicone oil, for preventing foaming upon bubbling of air through oil containing a few percent of the additive.

It is intended to claim the invention broadly, except as limited by the following claims.

I claim:

1. A reaction product of about 15 to about 44 parts by weight of phosphorus pentasulfide, about 25 to about parts by weight of an ester selected from the group consisting of hydrogenated sperm oil, babassu oil and degras, and about 25 to about 75 parts by weight of a polyolefin selected from the group consisting of polypropenes and polybutenes having a molecular weight within the range from about to about 940, and mixtures thereof, reacted together simultaneously at a temperature in the range of about 250 to about 350 F. to produce an oil-dispersible material suitable for improving the characteristics of a mineral lubricating oil.

2. A reaction product in accordance with claim 1 in which the polyolefin is reduced motor polymer.

3. A reaction product in accordance with claim 1 in which the ester is degras.

4. A reaction product in accordance with claim 1 in which the ester is hydrogenated sperm oil.

JOHN M. MUSSELMAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,063,629 Salzberg Dec. 8, 1936 2,316,082 Loane Apr. 6, 1943 2,343,831 Osborne Mar. 7, 1944 2,365,938 Cook et al. Dec. 26, 1944 2,373,094 Berger et al Apr. 10, 1945 2,381,377 Angel et al Apr. 10, 1945 2,411,153 Fuller Nov. 19, 1946 2,415,837 Musselman Feb. 18, 1947 2,422,206 Musselman June 17, 1947 2,461,961 Buckman et a1 Feb. 15, 1949 2,483,571 Brennan Oct. 4, 1949 OTHER REFERENCES Lubricating Oil Additives-G. G. Pritzker- Reprinted from Technical Sec.-Natl. Petroleum NewsOct., Nov., and Dec, 1945-pgs. 17-23.

Claims (1)

1. A REACTION PRODUCT OF ABOUT 15 TO ABOUT 44 PARTS BY WEIGHT OF PHOSPHORUS PENTASULFIDE, ABOUT 25 TO ABOUT 75 PARTS BY WEIGHT OF AN ESTER SELECTED FROM THE GROUP CONSISTING OF HYDROGENATED SPERM OIL, BABASSU OIL AND DEGRAS, AND ABOUT 25 TO ABOUT 75 PARTS BY WEIGHT OF A POLYOLEFIN SELECTED FROM THE GROUP CONSISTING OF POLYPROPENES AND POLYBUTENES HAVING A MOLECULAR WEIGHT WITHIN THE RANGE FROM ABOUT 145 TO ABOUT 940, AND MIXTURES THEREOF, REACTED TOGETHER SIMULTANEOUSLY AT A TEMPERATURE IN THE RANGE OF ABOUT 250 TO ABOUT 350* F. TO PRODUCE AN OIL-DISPERSIBLE MATERIAL SUITABLE FOR IMPROVING THE CHARACTERISTICS OF A MINERAL LUBRICATING OIL.