LUBRICATING COMPOSITIONS

Abstract

A liquid composition for providing enhanced lubrication and wear protection, particularly under high-performance and/or extreme-pressure conditions. The composition comprises components that are solubilized, liquified, liquefacted, or sub-micronized, and are formulated to result in a stable, color-tunable composition that can be stored or implemented over extended periods of time without separation of solid components from the liquid. A composition can be a lubricant in which the solubilized, liquified, liquefacted, and/or sub-micronized components are comprised within a base oil, or an additive composition in which the components are formulated to be later added to a base oil. Suitable base oils are industrial, automotive, or open gear oils such as those used in the oil and gas industry, sugar mills, or in rock crushers; rock drill, pneumatic, and air tool oils; anti-seize compounds; cutting, gun, engine, air compressor, or bearing oils; slideway lubricants; and oven, kiln, foundry, metalworking, metalforming, or aerospace lubricants.

Claims

1. A liquid composition formulated to provide enhanced lubrication and anti-wear properties under extreme pressure conditions, the composition comprising: from about 0.25% by weight and up to about 6% by weight of one or more transition metal lubricants, the transition metal lubricants selected from the group consisting of liquefacted tungsten disulfide, liquefacted molybdenum disulfide, a liquid molybdenum complex, and any combination thereof, wherein the liquid molybdenum complex comprises an oil-soluble molybdenum salt selected from the group consisting of molybdenum alkyl dithiophosphate, molybdenum alkyl dithiocarbamate, and any combination thereof; and up to about 5% by weight of liquefacted boron nitride, the liquefacted boron nitride prepared from the solvation of exfoliated solid boron nitride within a liquid carrier, wherein the composition is homogeneous and has no visible suspended or settled particles, and wherein the balance is a base oil.

2. The composition according to claim 1, wherein the composition further comprises up to about 10% by weight of a surface treatment mixture, wherein the surface treatment mixture comprises at least one hydrogenated paraffinic or naphthenic petroleum distillate.

3. The composition according to claim 2, wherein the composition further comprises up to about 0.5% by weight of an inorganic fluoride salt selected from the group consisting of: calcium fluoride; lithium fluoride; magnesium fluoride; and any combination thereof.

4. The composition according to claim 3, wherein the inorganic fluoride salt is solubilized within a mixture of one or more oil-soluble weak organic acids and one or more oil-soluble strong organic acids, forming an inorganic fluoride salt composition, wherein the composition further comprises up to about 5% by weight of the inorganic fluoride salt composition, wherein the one or more oil-soluble weak organic acids are selected from the group consisting of: an alkyl carboxylic acid; an aryl carboxylic acid; a Lewis acid having a pKa greater than about 4.0; and any combination thereof, and wherein the one or more oil-soluble strong acids are selected from the group consisting of: an alkyl sulfonate; an aryl sulfonate; a phosphate acid having a pKa lower than about 4.0; and any combination thereof.

5. The composition according to claim 3, wherein the transition metal lubricant comprises a liquid molybdenum complex.

6. The composition according to claim 5, wherein the composition further comprises up to about 10% by weight of a molybdenum activator, wherein the molybdenum activator comprises two or more sulfurized lubricant additive compounds, the two or more sulfurized lubricant additive compounds selected from the group consisting of: a sulfurized methyl ether; a sulfurized fat; a sulfurized olefin; an alkyl dithiocarbamate; an alkyl dithiophosphate; an alkyl dimercaptothiadiazole; and any combination thereof.

7. The composition according to claim 5, wherein the composition further comprises up to about 5% by weight of a polymeric dispersant, the polymeric dispersant comprising one or more oil-soluble copolymers of olefins having a polymeric amine core.

8. The composition according to claim 7, wherein the composition further comprises up to about 15% by weight of a viscosity modifier.

9. The composition according to claim 8, wherein the composition further comprises up to about 2% by weight of a colorant.

10. The composition according to claim 5, wherein the composition further comprises up to about 15% by weight of a viscosity modifier.

11. The composition according to claim 5, wherein the composition further comprises up to about 2% by weight of a colorant.

12. The composition according to claim 2, wherein the composition further comprises up to about 5% by weight of a polymeric dispersant, the polymeric dispersant comprising one or more oil-soluble copolymers of olefins having a polymeric amine core.

13. The composition according to claim 12, wherein the composition further comprises up to about 15% by weight of a viscosity modifier.

14. The composition according to claim 13, wherein the composition further comprises up to about 2% by weight of a colorant.

15. The composition according to claim 2, wherein the composition further comprises up to about 15% by weight of a viscosity modifier.

16. The composition according to claim 15, wherein the composition further comprises up to about 2% by weight of a colorant.

17. The composition according to claim 1, wherein the composition further comprises up to about 0.5% by weight of an inorganic fluoride salt selected from the group consisting of: calcium fluoride; lithium fluoride; magnesium fluoride; and any combination thereof.

18. The composition according to claim 17, wherein the inorganic fluoride salt is solubilized within a mixture of one or more oil-soluble weak organic acids and one or more oil-soluble strong organic acids, forming an inorganic fluoride salt composition, wherein the composition further comprises up to about 5% by weight of the inorganic fluoride salt composition, wherein the one or more oil-soluble weak organic acids are selected from the group consisting of: an alkyl carboxylic acid; an aryl carboxylic acid; a Lewis acid having a pKa greater than about 4.0; and any combination thereof, and wherein the one or more oil-soluble strong acids are selected from the group consisting of: an alkyl sulfonate; an aryl sulfonate; a phosphate acid having a pKa lower than about 4.0; and any combination thereof.

19. The composition according to claim 1, wherein the composition further comprises up to about 5% by weight of a polymeric dispersant, the polymeric dispersant comprising one or more oil-soluble copolymers of olefins having a polymeric amine core.

20. The composition according to claim 1, wherein the composition further comprises up to about 15% by weight of a viscosity modifier.

Description

DETAILED DESCRIPTION OF THE INVENTION

Definitions

[0062] Unless otherwise provided, the terms listed herein have the meaning provided below.

[0063] Other than in any operating examples, or where otherwise indicated, all numbers expressing quantities of composition components, reaction conditions, and the like that are used in the specification and claims are understood as being modified in all instances by the term, about. Accordingly, the term about is used to describe approximations of numerical parameters set forth in the specification and claims that may vary depending upon the desired properties to be obtained by the present invention. At the very least, and not an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed relative to the number of reported significant digits and by applying ordinary rounding techniques.

[0064] The terms acid value and acid number are interchangeably used to describe the amount of carboxylic acid groups present within an inorganic fluoride salt composition to solubilize an inorganic fluoride salt, and are typically expressed as milligrams of potassium hydroxide required to titrate a 1-gram sample to a specified endpoint. Methods for determining acid values are well-known in the art, and are defined, for example, according to ISO 2114-2000 and ASTM D974-04 (Standard Test Method for Acid and Base Number by Color-Indicator Titration).

[0065] The terms hydroxyl number, hydroxyl value, base value, and base number are all interchangeably used to describe the ability of a lubricant or additive composition to neutralize acids formed during engine operation, are typically expressed as milligrams of potassium hydroxide required to titrate a 1-gram sample to a specified endpoint. In some embodiments, the base number can be adjusted upon the addition of a polymeric dispersant and/or viscosity modifier to the composition. Methods for determining base values are well-known in the art, and are defined, for example, according to ISO 4629-1978 and ASTM D1957-86 (Standard Test Method for Hydroxyl Value of Fatty Oils and Acids), or ISO 2114-2000 and ASTM D974-04 (Standard Test Method for Acid and Base Number by Color-Indicator Titration).

[0066] The term, group is used to describe a chemical substituent, and includes the unsubstituted group and that group with O, N, Si, or S atoms, for example, in the chain (as in an alkoxy group) as well as carbonyl groups or other conventional substitution. As a non-limiting example, the phrase alkyl group is intended to include not only pure open chain saturated hydrocarbon alkyl substituents, such as methyl, ethyl, propyl, t-butyl, and the like, but also alkyl substituents bearing further substituents known in the art, such as hydroxy, alkoxy, alkylsulfonyl, halogen atoms, cyano, nitro, amino, carboxyl, etc. Thus, alkyl group includes ether groups, haloalkyls, nitroalkyls, carboxyalkyls, hydroxyalkyls, sulfoalkyls, etc. As used herein, the term group is intended to be a recitation of both a particular moiety, as well as a recitation of the broader class of substituted and unsubstituted structures that includes the moiety.

[0067] The term, moiety is used to describe a chemical compound or substituent, only an unsubstituted chemical material is intended to be included. As a non-limiting example, the phrase alkyl moiety can be limited to the inclusion of only pure open chain saturated hydrocarbon alkyl substituents, such as methyl, ethyl, propyl, t-butyl, and the like.

[0068] The term number average molecular weight (M.sub.n) is used to describe a method of reporting the average molecular weight of polymers in a mixture, calculated by dividing the total weight of all of the polymers in the sample divided by the number of polymers in a sample, using the equation,

[00001]${\stackrel{\_}{M}}_N=\frac{{.Math.}_i{N}_i{M}_i}{{.Math.}_i{N}_i},$

wherein N.sub.i is the number of polymers of molecular mass M.sub.i.

[0069] The term polymer includes both homopolymers and copolymers (i.e., polymers of two or more different monomers). Similarly, unless otherwise indicated, the use of a term designating a polymer class such as, for example, polyester is intended to include both homopolymers and copolymers (e.g., polyester-urethane polymers).

[0070] The terms preferred and preferably refer to embodiments of the invention that may afford certain benefits, under certain circumstances. However, other embodiments may also be preferred, under the same or other circumstances. Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, and is not intended to exclude other embodiments from the scope of the invention.

[0071] The term wear scar refers to a metric used to determine the quality of oils and their lubricity, based on evaluating the anti-wear properties of fluid lubricants in sliding contact. Methods for evaluating the anti-wear properties by measuring wear scar diameters are well-known in the art. As a non-limiting example, the wear properties of lubricating oils and greases can be determined according to the ASTM D2255 or D4172 four-ball wear test methods, in which three steel balls are clamped together and covered with a lubricant oil or grease, and a fourth steel ball is pressed into the other steel balls at a selected force. After some time, the wear scars on the steel balls are measured, typically on a millimeter scale, and average wear scars can be compared across multiple lubricant formulations. As another non-limiting example, the wear properties of lubricating oils and greases under extreme pressure conditions can be determined according to the ASTM D2596 or D2783 extreme pressure (EP) four-ball wear test methods, which are measured similarly to ASTM D2255 or D4172 four-ball wear test methods but under higher force loads.

[0072] The term, load wear index (LWI) refers to a weighted average of wear scars measured for force loads prior to welding, in which higher values indicate increased extreme-pressure lubricant performance.

[0073] The term coefficient of friction refers to a dimensionless number that is defined as the ratio between friction force and normal force. Generally, compositions having a lower coefficient of friction relative to others are considered more lubricious, and in some embodiments, compositions of the present invention can have coefficient-of-friction (COF) values less than 0.3, 0.25, 0.2, 0.15, or 0.1, down to less 0.05. Methods for determining a composition's COF are well-known in the art. As a non-limiting example, ASTM D1894-14 is a widely-used method for COF measurement. However, and in some embodiments, equipment used to evaluate in ASTM methods D2255, D2596, D2783, or D4172 can also be adapted to measure the COF as well as wear-scar diameter.

[0074] In describing features herein as pertaining to any of the various embodiments or in various embodiments, the described feature should be understood to be capable of being combined with any other features and embodiments described within the description, unless such combination or use would be clearly unreasonable or contradict the usefulness or purpose of the described feature.

[0075] As used herein, a, an, the, at least one, and one or more are used interchangeably. Thus, for example, a coating composition that comprises an additive can be interpreted to mean that the coating composition includes one or more additives.

[0076] Also herein, the recitations of numerical ranges by endpoints include all numbers subsumed within that range (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, 5, etc.). Furthermore, disclosure of a range includes disclosure of all sub-ranges included within the broader range (e.g., 1 to 5 discloses 1 to 4, 1.5 to 4.5, 1 to 2, etc.). It will be understood that the total sum of any quantities expressed herein as percentages cannot (allowing for rounding errors) exceed 100%.

Exemplary Embodiments of the Present Invention

[0077] The compositions of the invention are formulated to provide increased protection over present lubricants, oils, and greases, particularly when operating under high-performance, high-temperature, and/or extreme-pressure conditions. In particular, the compositions are formulated to prevent the fallout of dispersed insoluble particles that is common in many lubricant formulations, such as those described in U.S. Pat. No. 9,206,377, which is herein incorporated by reference in its entirety. In some embodiments, the compositions can comprise all liquid, liquefacted, and/or sub-micronized components, such that where particles are present, they remain dispersed homogeneously throughout the composition with no fallout. Without being limited by a particular theory, it is believed that the sub-micronizing, liquefacting, and/or liquifying otherwise insoluble components, particularly molybdenum-containing components, the color of the composition can be controlled and maintained for extended periods of time, either in storage or on the lubricated surface itself.

[0078] The following working and prophetic examples illustrate the embodiments of the invention that are presently best known. However, it is to be understood that the following are only exemplary or illustrative of the application of the principles of the present invention. Numerous modifications and alternative compositions, methods, and systems may be devised by those skilled in the art without departing from the spirit and scope of the present invention. Thus, while the present invention has been described above with particularity, the following examples provide further details in connection with both practical and preferred embodiments of the invention.

Product Formulation

[0079] Several of the lubricant and additive compositions indicated in the examples below were prepared according to the following procedure. Without being limited by a particular theory, it is believed that a person of ordinary skill in the art could prepare compositions within any of the prophetic examples below using the same procedure, or a similar procedure modified without undue experimentation.

[0080] Lubricant compositions of the present invention were prepared by adding each of the individual components to a base oil in a mixing kettle with constant mixing. Components were typically added in order from components having the highest viscosity to the lowest viscosity. Each component was stirred for fifteen to twenty minutes to ensure full mixing, prior to adding the next component. Mixing generally was performed at 60 C., but can alternatively be performed at 40 C. or ambient temperature. Once all components have been added, composition are cooled to ambient temperature, prior to filtering and packaging into a drum, tote, bottle, bulk tanker, or other receptacle.

[0081] Additive compositions of the present invention can be prepared similarly to the lubricant compositions regarding order of addition, mixing time, mixing speed, and/or cooling steps.

Composition Components

[0082] Generally, each of the components listed and described below are commercially available and can directly be added and mixed into any of the compositions described herein without having to be chemically or physically modified. However, instances where a commercially-obtained product is modified prior to formulation are indicated.

Inorganic Lubricants

[0083] Transition metal compounds such as molybdenum disulfide, tungsten carbide, and tungsten disulfide, as well as other inorganic compounds such as boron nitride and graphite, are commonly-known additives for reducing friction. Each of the compounds is most commonly available with mean particle sizes of about one to thirty microns, which makes them well-suited for dispersion within a liquid carrier when formulating lubricant compositions. Of the inorganic compounds above, molybdenum disulfide is often selected because of its cost, availability, high operating temperature capability and overall long-term performance. A non-limiting example of commercially-available molybdenum disulfide is Bonderite S-AD 1286 Acheson solid lubricant additive (also known as SLA 1286), sold by Henkel Corporation.

[0084] In many instances, molybdenum disulfide is provided as a mixture with graphite, where the ratio of molybdenum disulfide to graphite is in a range from about 3:7, up to about 7:3. A non-limiting example of commercially-available micron-sized graphite is Bonderite L-GP OILDAG. However, as described above, compositions containing inorganic compounds in solid form are prone to fallout, wherein over time, the compositions can separate into multiple layers which either require additional processing to re-disperse the particles into a liquid layer, or cannot be recovered at all.

[0085] Therefore, and in some embodiments, organic molybdenum can be utilized within any of the compositions described herein as a substitute for molybdenum disulfide. Typical organic molybdenum are Molybdenum dithiocarbamates (MoDTC), molybdenum dialkyl dithiophosphate (MoDTP), molybdenum dialkyldithiophosphate (MoDDP) and molybdenum amide. Without being limited by a particular theory, it is believed that the tribo-chemical decomposition of organic molybdenum can generate molybdenum disulfide in situ, reducing the coefficient of friction between the two or more surfaces.

[0086] Advantageously, many organic molybdenum compounds, including MoDTC, MoDTP, MoDDP and molybdenum amide are soluble on oil, and can be included in a lubricant or additive composition without exhibiting fallout. Additional discussion of organic molybdenum can be found, for example, in Wang, W, et al., (2021) Tribological performance of organic molybdenum in the presence of organic modifier PLoS ONE 16(6):e0252203, the disclosure of which is herein incorporated by reference in its entirety. One non-limiting example of a commercially-available organic molybdenum is Molyvan 3000, which is a MoDTC friction reducer that is soluble at low-or ambient temperatures in a variety of base oils, including passenger motor oils, greases, industrial oils, and heavy-duty diesel engine oil, and is available from Vanderbilt Chemicals.

[0087] Nonetheless, and in other embodiments, micron-scale inorganic compounds can also be utilized in any of the lubricant or additive compositions described herein, upon physically processing the compounds until they have sub-micron particle sizes, particularly below 100 nm. One non-limiting example of a process for sub-micronizing inorganic compounds is mechanical exfoliation. In some embodiments, any one or more of tungsten disulfide, tungsten carbide, molybdenum disulfide, boron nitride, and graphite can be mechanically exfoliated by using a ball mill or similar apparatus to apply a mechanical shear to the particles, which are then combined into a composition by suspending them in a carrier in liquid phase, solid phase, or a mixture of solid and liquid phases. Non-limiting examples of liquid carriers are aqueous suspensions, organic solvents, organic liquids, oils, molten polymers, silicones, molten salts, and other low-melting point systems. Non-limiting examples of solid carriers are powders comprising organic compounds, polymer powders, or pellets below their glass transition temperature, at the glass transition temperature, and/or above the glass transition temperature, and inorganic powders such as ceramic and glass powders, metals, etc.

[0088] In various embodiments, sub-micronized inorganic compounds can be liquefacted into a liquid phase or a liquid-like phase that behaves like a fluid. One non-limiting example for liquefacting sub-micronized particles is chemical exfoliation, in which the particles are dispersed directly within a solvent, to facilitate later reconstitution as a film with one or more additional materials to form hybrids or composites useful in the electronics and energy industries (see, e.g., Coleman, J. N., et al., (2011) Science 331:568-571, the disclosure of which is herein incorporated by reference in its entirety). Particularly, the authors reported that sonication of boron nitride within isopropyl alcohol formed a solution that was translucent and stable for several hundred hours, with less than 20% of the boron nitride precipitating out of solution after one week.

[0089] In contrast, and in various embodiments, combination of liquefacted boron nitride with one or more additional liquid components described below can result in a stable lubricant composition having no suspended or settled particles, that can be utilized and/or stored for non-limiting exemplary periods of up to 1 month, 3 months, 6 months, 9 months, 1 year, 2 years, or 5 years with no fallout. In a further embodiment, lubricant compositions containing liquefacted boron nitride can be stored indefinitely with no particle fallout.

[0090] More details regarding mechanical exfoliation, as well as chemical exfoliation, are described in U.S. Patent Pub. No. 2016/0325994, the disclosure of which is herein incorporated by reference in its entirety.

[0091] Boron nitride can be obtained commercially in an already liquid-exfoliated form, a non-limiting example of which is Functional Ceramax Fluid, sold by Functional Products Inc, and which is provided within a mixture of aromatic hydrocarbons and esters at a boron nitride concentration of about 25% by weight. A non-limiting example of a micron-sized boron nitride that can be further exfoliated to form sub-micronized or liquefacted boron nitride is Bonderite S-AD 1720. In some embodiments, exfoliated boron nitride can be prepared as a liquid within any mixture of synthetic or petroleum hydrocarbons and dispersants. Such boron nitride-containing compositions are generally clear, low color, and stable.

Molybdenum Activator

[0092] In some embodiments, a molybdenum activator can be used in combination with organic molybdenum to enhance the extreme-pressure loading characteristics and achieve comparable extreme-pressure performance to molybdenum disulfide while retaining the excellent wear and friction reduction of organic molybdenum. In some embodiments, a molybdenum activator is a specific and balanced blend of two to four components from different families of sulfurized lubricant additives: sulfurized methyl esters, fats, or olefins; alkyl derivatives of dithiocarbamate, dithiophosphate; and/or alkyl dimercaptothiadiazole. A non-limiting example of a commercially-available molybdenum activator is Functional EP-203, sold by Functional Products Inc. Other commercially-available brands include Lanxess Additin RC 2400 and 2500 series, Dover EP portfolio, Seqens Sulfad portfolio, and Dailube GS and IS series.

Surface Treatment Mixture

[0093] In some embodiments, a surface treatment mixture can be added to the composition to improve metal surface characteristics by creating a stable, chemical corrosion-controlled boundary film. In some embodiments, the surface treatment mixture can comprise one or more petroleum distillates, which can be obtained by treating petroleum fractions with hydrogen to form a variety of low-or no-sulfur saturated hydrocarbon products. Depending on the reaction conditions (temperature, pressure, catalyst activity) and weight fraction of the starting material, a wide variety of short-, medium- and long-chain paraffinic distillates can be generated, including n-alkanes, isoalkanes, and naphthenes. Typically, the paraffinic distillates are produced as complex mixtures containing thousands of homologs and isomers. In some embodiments, paraffinic distillate products can be processed further in the presence of chloring gas under UV light to form chlorinated paraffinic distillates, which may further enhance the metal surface characteristics. Two non-limiting examples of commercially-available surface treatment mixtures comprising hydrotreated paraffinic and/or naphthenic petroleum distillates are Muscle Hybrid Engine Treatment and Metal Treatment MT-10, both of which are sold by Muscle Products Corp.

Inorganic Salt Solubilizer

[0094] Many inorganic salts, examples of which include but are not limited to inorganic sodium, calcium, and lithium salts, are insoluble in oil-based systems. As described above, such salts, particularly inorganic fluoride salts, can be solubilized in specially-designed solubilizing compositions. Without being limited by a particular theory, it is believed that the reaction of the inorganic salt is promoted by the combination of a catalyst, heating, and mixing for a prescribed amount of time. The resulting dispersion can then be added directly into the lubricant or additive composition production batch, and can remained dispersed and stable once diluted.

[0095] One non-limiting example of an inorganic salt solubilizer is Functional SD-38, sold by Functional Products Inc., and which contains a synergistic mixture of at least one weak oil-soluble organic acid and one strong oil-soluble organic acid to form an inorganic salt composition. Non-limiting examples of suitable weak organic acids are alkyl or aryl carboxylic acids, boric acid, and Lewis acids with pKa>4. Non-limiting examples of suitable strong organic acids are alkyl or aryl sulfonates, phosphates with pKa<4.

[0096] To form the inorganic fluoride salt compositions indicated below, 8.5 parts by weight of the Functional SD-38 were combined with one part calcium fluoride and 0.5 parts of water. The batch was heated to 60 C. and mixed for four hours, as needed, until a color change to yellow, tan, or orange indicated that the solubilization was complete.

Polymeric Dispersant

[0097] Polymeric dispersants utilized in the production of the compositions in the examples below were composed of oil soluble copolymers of olefins (ethylene, propylene, butylene, etc.) with a polymeric amine core. This material is typical of ashless engine oil dispersants. Where present, the polymeric dispersant was used to adjust the total base number (TBN) of the finished lubricant as needed for the application, typically to meet regulatory guidelines. However, without being limited by a particular theory, it is believed that some polymeric dispersants are multi-functional additives and can provide other key benefits like corrosion inhibition, sludge/varnish control, and metal passivation. A non-limiting example of a commercially-available polymeric dispersant is Functional SD-55, which is sold by Functional Products Inc., and comprises an oil-soluble succinimide polyamine dispersant in a polyalphaolefin synthetic base fluid that is compatible with detergents, rust inhibitors, paraffin oils, and other typical industrial lubricant additives.

Viscosity Modifier

[0098] Viscosity index modifiers may be used to control the final viscosity of a lubricant formulation in several applications, non-limiting examples of which include multi-grade engine oils, industrial fluids, crankcase additives. Some viscosity modifiers can be formulated to offer high thickening efficiency, shear stability, demulsibility, and pour point depressancy. Non-limiting examples of commercially-available polymeric dispersants are Functional V-159 and Functional MH-2000, both of which are sold by Functional Products Inc.

[0099] Unless otherwise indicated, the following components were utilized in the examples below: the liquid molybdenum complex was Molyvan 3000; the boron nitride was Functional Ceramax Fluid, in which liquefacted boron nitride within a mixture of aromatic hydrocarbons and esters at a boron nitride concentration of about 25% by weight; the molybdenum activator was Functional EP-203; the surface treatment mixture was Muscle Hybrid Engine Treatment; the liquid calcium fluoride was calcium fluoride solubilized within Functional SD-38; the polymeric dispersant was Functional SD-55, and the viscosity modifier was either Functional V-159 or Functional MH-2000. Additionally, the concentration values of each of the compositions below are given as percent by weight, unless indicated otherwise.

Example 1: Preliminary Optimization for Automotive Gear Oils

[0100] Several compositions were generated to optimize coefficient of friction (COF), wear scar size, and load wear index. Preliminary work began with top treating a conventional 75W-90 oil with liquid molybdenum complex and molybdenum activator to produce high extreme pressure loads (Table 1). The baseline for the conventional 75W-90 with the surface treatment mixture was 500 kgf weld load with 3.88 mm scar and 0.497 COF at 400 kgf on ASTM D2783 4-ball extreme pressure test. Formula A3 and its specific ratio of liquid molybdenum complex and molybdenum activator were the best in terms of relatively low COF.

TABLE-US-00001 TABLE 1 Formula A0 A1 A2 A3 A4 A5 A6 A7 75W-90 Conventional Base Balance Surface Treatment Mixture 6.0 6.0 6.0 6.0 6.0 6.0 6.0 6.0 Liquid Molybdenum Complex 0.0 4.0 3.0 2.0 1.0 2.0 2.0 0.0 Molybdenum Activator 0.0 3.0 3.0 3.0 3.0 4.0 2.0 4.0 ASTM D2783, 620 kg Wear Scar, mm WELD WELD 2.9 3.0 3.5 3.1 3.0 WELD Coefficient of Friction >0.35 >0.35 >0.35 0.32 >0.35 >0.35 >0.35 >0.35

[0101] Preliminary work on determining the ratio of boron nitride and calcium fluoride indicated 0.5 wt % was an optimal concentration of boron nitride (Table 2).

TABLE-US-00002 TABLE 2 Formula A3 B1 B2 B3 B4 75W-90 Conventional Base Surface Treatment Mixture 6.0 6.0 6.0 6.0 6.0 Liquid Molybdenum Complex 2.0 2.0 2.0 2.0 2.0 Molybdenum Activator 3.0 3.0 3.0 3.0 3.0 Sub-micronized Boron Nitride 0.0 0.125 0.25 0.5 0.75 Liquid Calcium Fluoride 0.0 0.0 0.0 0.0 0.0 ASTM D2783, 620 kg Wear Scar, mm 3.0 WELD 3.6 2.9 3.0 Coefficient of Friction 0.32 >0.35 0.095 0.088 >0.3

[0102] As illustrated in Table 3, 0.5 wt % liquid calcium fluoride to 0.5 wt % boron nitride was found to be best ratio for wear. Lesser amounts of calcium fluoride (0.125-0.25 wt %) were antagonistic to wear scar performance. In both Table 2 and Table 3, it is shown that <1% of the boron nitride or calcium fluoride can have drastic effects on extreme-pressure properties. Without being limited by a particular theory, it is believed that the utility of these additives may not obvious as it would be very easy for formulators to undertreat and see negative effects on performance. Formula C3 was found to be the best optimization of boron nitride and calcium fluoride for the given 75W-90 conventional base formula and molybdenum complex/activator top treat.

TABLE-US-00003 TABLE 3 Formula B3 C1 C2 C3 75W-90 Conventional Base Surface Treatment Mixture 6.0 6.0 6.0 6.0 Liquid Molybdenum Complex 2.0 2.0 2.0 2.0 Molybdenum Activator 3.0 3.0 3.0 3.0 Sub-micronized Boron Nitride 0.5 0.5 0.5 0.5 Liquid Calcium Fluoride 0.0 0.125 0.25 0.5 ASTM D2783, 620 kg Wear Scar, mm 2.9 WELD 3.6 2.0 Coefficient of Friction 0.088 >0.3 >0.3 >0.3

[0103] As shown above in Table 3, the wear scar decreased in Formula C3 relative to B3, even though the COF itself increased. Without being limited by a particular theory, it is believed that an increased COF and a smaller wear scar may be an advantage in applications such as in railway lubricants, where the COF provides traction to move the train, and is more favorable for power transmission. It is also believed that a lower COF and larger wear scar can be advantageous when lubricating smaller equipment that can overheat easily, such as a saw, or when startup torque is required in heavily loaded gears in order to reduce the energy required to get the system moving.

Example 2: Formula Optimization for Heavy-Synthetic Gear Oils

[0104] Several compositions were generated to determine whether a different gear oil base formula (SAE 250) may affect the optimal ratio of the molybdenum complex and the molybdenum activator relative to each other.

[0105] As illustrated below in Table 4, when top treating an SAE 250 synthetic product, the optimal ratio of the liquid molybdenum complex to molybdenum activator was approximately 1:1. To optimize the COF under EP conditions it became important to also consider the scarring at 620 kg but also a lower value. 400 kgf was selected because that value is equivalent to the typical failure point of standard automotive gear oils, enabling optimization beyond wear other gear oils typically fail.

TABLE-US-00004 TABLE 4 Formula A0 A1 A2 A3 A4 A5 A6 A7 SAE 250 synthetic base balance Surface Treatment Mixture 6.0 6.0 6.0 6.0 6.0 6.0 6.0 6.0 Liquid Molybdenum Complex 0.0 2.0 3.9 6.0 2.0 3.9 3.9 6.0 Molybdenum Activator 0.0 0.0 0.0 0.0 2.5 2.5 3.0 2.5 Sub-micronized Boron Nitride 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Liquid Calcium Fluoride 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Weld Load, ASTM D2783 315 315 315 315 620 620 800 620 Wear Scar, mm @ 400 kgf n/a n/a n/a n/a 0.0859 0.0819 0.0733 0.0874 COF @ 400 kgf n/a n/a n/a n/a 1.114 1.023 0.940 1.142

[0106] As indicated in Table 4 above, Formula A6 produced the highest extreme-pressure weld load with the lowest COF and wear at lower extreme-pressure loading. Accordingly, not only can weld load and peak extreme-pressure be optimized, but the friction and wear at lower pressure-load levels can also be optimized to ensure performance across a wide range of extreme-pressure conditions.

Example 3: Optimization of Component Addition

[0107] Several compositions were generated to determine whether adding the surface treatment mixture last, instead of first, may be a key factor in allowing the liquid ceramic chemistry enough time to properly activate before metal-metal contact can begin. The relative concentrations of liquid molybdenum complex, molybdenum activator, boron nitride, and liquid calcium fluoride were optimized first (Tables 5-7, below).

TABLE-US-00005 TABLE 5 A1 A2 A3 A4 A5 A6 A7 A8 75W-90 Synthetic Gear Oil Base balance Liquid Molybdenum Complex 2.0 2.4 2.8 2.5 3.5 3.35 2.0 2.3 Molybdenum Activator 3.0 3.6 4.2 2.5 3.5 3.35 4.0 4.7 Sub-micronized Boron Nitride 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Liquid Calcium Fluoride 0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 ASTM D2783, 4-ball EP Wear Scar @ 400 kgf 1.75 1.58 1.46 1.73 1.48 1.46 COF @ 400 kgf 0.0893 0.0882 0.0841 0.0943 0.0815 0.0863 Wear Scar @ 620 kg 3.1 >4.0 1.8 2.0 COF @ 620 kg 0.0862 >0.35 0.0643 0.0685

[0108] Beginning from A7, the levels were boron and fluoride were checked and adjusted for optimal ratio (Table 6). A 1:1 ratio was again found to be most favorable for balancing extreme-pressure wear and COF in Formula B2.

TABLE-US-00006 TABLE 6 A7 B1 B2 B3 B4 75W-90 Synthetic Gear Oil Base balance Liquid Molybdenum Complex 2.0 2.0 2.0 2.0 2.0 Molybdenum Activator 4.0 4.0 4.0 4.0 4.0 Sub-micronized Boron Nitride 0.5 0.25 0.5 0.5 0.75 Liquid Calcium Fluoride 0.25 0.13 0.5 0.75 0.38 ASTM D2783, 4-ball EP Wear Scar @ 400 kgf 1.46 1.48 1.25 1.46 COF @, 400 kgf 0.0863 0.08726 0.0808 0.0819 Wear Scar @ 620 kg 1.8 WELD 1.6 2.1 1.94 COF @ 620 kg 0.0643 >0.35 0.0649 0.0661 0.0685

[0109] Formula B2 produced good ASTM D4172 wear scars and great ASTM D2783 EP performance. However, COF at lower wear levels like 200 kgf were increased while COF at very high EP loads 400+ were low, producing a skewed, bell curve-like performance profile (Table 7).

TABLE-US-00007 TABLE 7 Wear Scar, mm COF ASTM D4172 @ 15 kg 0.304 0.0561 ASTM D4172 @ 40 kg 0.441 0.0693 ASTM D2783 EP @ 200 kg 0.984 0.146 ASTM D2783 EP @ 400 kg 1.06 0.0856 ASTM D2783 EP @ 620 kg 3.08 0.0868 ASTM D2783 EP @ 800 kg WELD >0.35

[0110] 1-8% Surface Treatment Mixture was added to Formula B3, and the wear scar and coefficient of friction were evaluated under 200 kg load (Table 8).

TABLE-US-00008 TABLE 8 Surface Treatment Wear Scar COF Mixture (w/w) @ 200 kg 200 kg 0% 0.984 0.146 1% 1.001 0.157 2% 0.987 0.161 4% 0.991 0.166 6% 0.961 0.156 8% 0.913 0.157

[0111] It was determined that adding the surface treatment mixture last had little effect on the extreme-pressure properties at a relatively low 200 kgf extreme-pressure load. 6 wt % was found to be optimal if any surface treatment mixture were to be added which improved the 40 kgf ASTM D4172 wear scar and COF to 0.393 mm and 0.0689, respectively. Without being limited by a particular theory, it is believed that though no major effects were found in ASTM D2783 EP testing, it may be preferable to include the surface treatment mixture which is active in other EP/scuffing tests like Timken OK ASTM D2782. Formula B3, with 6% surface treatment mixture included, results in an ASTM D2783 EP load vs. wear scar profile that produces a load wear index of 140 (Table 9), which is approximately two times higher than the industry leader in 75W-90 full synthetic GL-5 gear oil (72), identified in a 2007 Amsoil Automotive Gear Oil Study.

TABLE-US-00009 TABLE 9 Load, kgf 126 160 200 250 315 400 500 620 Wear Scar, mm 0.396 0.841 0.961 0.991 0.989 1.035 1.142 WELD COF 0.0656 0.166 0.156 0.136 0.111 0.0890 0.0782 n/a

Example 4: Optimization for 15W-40 and 10W-30 Engine Oils

[0112] Several compositions were generated to determine optimized concentration values for components within a lubricant composition in which the base oil is a 15W-40 Heavy Duty Diesel Engine Oil. Primary formulation began with the liquid molybdenum and surface treatment mixture additives at 1-5wt % using a 22 grid of different treat rates (Table 10). Molybdenum activator was excluded to limit the sulfur content, which is tightly controlled by most engine-oil regulating bodies.

TABLE-US-00010 TABLE 10 Components by wt % A0 A1 A2 A3 A4 A5 15W-40 Base Formula 100 95.6 92.6 94.2 91.2 92.8 Liquid Molybdenum Complex 0.0 1.4 1.4 2.8 2.8 4.2 Surface treatment mixture 0.0 3.0 6.0 3.0 6.0 3.0 ASTM D4172 Wear at 40 kg Wear Scar Diameter, mm 0.309 0.371 0.341 0.314 0.337 0.259 Coefficient of Friction 0.0862 0.0979 0.0734 0.0940 0.0994 0.0757

[0113] Formula A5 demonstrated significant anti-wear and COF improvement and served as the foundation for building the ceramic formulation. Fine adjustment was made on Formula A5 using the boron nitride and liquid calcium fluoride at a fixed total wt % of about 1-1.1% (Table 11).

TABLE-US-00011 TABLE 11 Components by wt % A5 B1 B2 B3 15W-40 Base 92.8 91.7 91.7 91.8 Formula Liquid 4.2 4.2 4.2 4.2 Molybdenum Complex Surface treatment 3.0 3.0 3.0 3.0 mixture Sub-micronized 0.0 0.2 0.9 0.5 Boron Nitride Liquid Calcium 0.0 0.9 0.2 0.5 Fluoride ASTM D4172 Wear at 40 kg Wear Scar 0.259 0.285 0.334 0.291 Diameter, mm Coefficient of 0.0757 0.0819 0.1010 0.0685 Friction

[0114] Surprisingly, a different optimal ratio of boron nitride to calcium fluoride was found versus result reported in U.S. Pat. No. 9,206,377, incorporated by reference above in its entirety. A 1:1 ratio of the boron nitride to liquid calcium fluoride corresponds to an approximately 2:1 BN/CaF.sub.2 ratio by weight, which is opposite the 1:2 BN/CaF.sub.2 ratio preferred in U.S. Pat. No. 9,206,377. Also surprisingly, this 1:1 ratio for the boron nitride to liquid calcium fluoride is the same optimal ratio observed in Examples 1-3 above. Of the formulas in Table 11, Formula B3 was deemed best due to the lowest COF with wear below 0.30 mm.

[0115] The total base number (TBN) and kinematic viscosity of Formula B3 was adjusted using polymeric dispersant and viscosity modifier, to reestablish the original TBN and viscosity of the base 15W-40 product, illustrated by Formula C1 in Table 12, below. Without being limited by a particular theory, it is believed that the use of polymeric dispersant and viscosity modifier also provides an extra safety factor to prevent any potential long-term fallout that could occur in storage (in addition to all the additives being liquid and oil-soluble), and that the polymeric dispersant also helps neutralize any residual acids (TAN) from the liquid calcium fluoride solubilizer.

TABLE-US-00012 TABLE 12 Components by wt % B3 C1 15W-40 Base Formula 91.8 91.8 Liquid Molybdenum Complex 4.2 4.2 Surface treatment mixture 3.0 3.0 Sub-micronized Boron Nitride 0.5 0.5 Liquid Calcium Fluoride 0.5 0.5 Polymeric Dispersant 0.0 4.0 Viscosity Modifier 0.0 2.0 ASTM D4172 Wear at 40 kg Wear Scar Diameter, mm 0.291 0.258 Coefficient of Friction 0.0685 0.0649

[0116] The same combination of components was also tested to a 10W-30 passenger car oil. A comparison of the formulas with the different base oils is illustrated in Table 13, below.

TABLE-US-00013 TABLE 13 Components by wt % C1 (15W-40) D1 (10W-30) 15W-40 Base Formula 91.7 0.0 10W-30 Base Formula 0.0 91.7 Liquid Molybdenum Complex 4.2 4.2 Surface treatment mixture 3.0 3.0 Sub-micronized Boron Nitride 0.5 0.5 Liquid Calcium Fluoride 0.5 0.5 Polymeric Dispersant 4.0 4.0 Viscosity Modifier 2.0 2.0 ASTM D4172 Wear at 40 kg Wear Scar Diameter, mm 0.258 0.270 Coefficient of Friction 0.0649 0.0755

[0117] As shown in Table 13, Formula C1 and Formula DI exhibit very similar wear scar diameter and COG results, within the apparent batch-to-batch variation. Without being limited by a particular theory, it is believed that for engine oils, the combination of components appears to act independently of the natural components of the 10W-30 and 15W-40 base oils, and the apparently optimized 1:1 ratio for the boron nitride to liquid calcium fluoride is also maintained across both engine base oils.

Example 5: Optimization for Hydraulic Oils

[0118] Without being limited by a particular theory, it is believed that industrial fluids like hydraulic oil have a well-known need for lower wear and friction which results in higher efficiencies in both the rate of work and fuel savings. Accordingly, a hydraulic fluid was prepared using a base ISO 46 rust and oxidation (R&O) inhibited oil (Table 14, below). Due to the lower operating temperatures and lack of extreme-pressure conditions the molybdenum activator was removed. Calcium fluoride was also excluded to evaluate the performance of only chlorine, molybdenum, and boron components.

TABLE-US-00014 TABLE 14 Components by wt % A0 A1 A2 A3 A4 A5 A6 A7 ISO 46 R&O oil 100 99 98 97 97 95 97.5 96 Liquid Molybdenum Complex 0.75 1.5 2.25 0.75 0.75 1.5 1.5 Sub-micronized Boron Nitride 0.25 0.5 0.75 0.25 0.25 0.5 0.5 Surface treatment mixture 0 0 0 0 2 4 0.5 2 ASTM D4172, @ 40 kg Wear Scar Diameter, mm 0.468 0.453 0.372 0.359 0.376 0.412 0.287 0.428 Coefficient of Friction 0.0647 0.0575 0.0726 0.0683 0.0679 0.0736 0.0691 0.0604

[0119] As illustrated in Table 14, Formula A6 offers exceptional performance in terms of wear and COF reduction at <0.3 mm wear scar by ASTM D4172 at 40 kgf load. However, and without being limited by a particular theory, it is believed that any formulation with <0.4 mm wear could potentially be a candidate for further development with hydraulic fluid base oils.

[0120] Further investigation was made into balancing the ratio of liquid molybdenum complex to boron nitride at a fixed 1wt % (Table 15, below). Without being limited by a particular theory, it is believed that Formula B3 exhibited an ideal ratio of 3:1 liquid molybdenum complex to boron nitride for greatly reducing friction. Wear scar diameter appeared to exhibit two regimes of behavior with moderate wear scar diameters (<0.5 mm) at >0.5wt % liquid molybdenum and high wear scar diameters (>0.5 mm) at <0.5wt % liquid molybdenum.

TABLE-US-00015 TABLE 15 Components by wt % B0 B1 B2 B3 B4 B5 B6 B7 ISO 46 R&O Oil 100 99 99 99 99 99 99 99 Liquid Molybdenum Complex 1.0 0.875 0.75 0.6 0.5 0.4 0.25 Sub-micronized Boron Nitride 0.0 0.125 0.25 0.4 0.5 0.6 0.75 ASTM D4172, 40 kgf Wear Scar Diameter, mm 0.468 0.429 0.449 0.453 0.462 0.635 0.833 0.599 Coefficient of Friction 0.0647 0.0645 0.0725 0.0575 0.0876 0.0769 0.1042 0.0882

[0121] While particular embodiments of the invention have been described, the invention can be further modified within the spirit and scope of this disclosure. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, numerous equivalents to the specific procedures, embodiments, claims, and examples described herein. As such, such equivalents are considered to be within the scope of the invention, and this application is therefore intended to cover any variations, uses or adaptations of the invention using its general principles. Further, the invention is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the appended claims.

[0122] It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination or as suitable in any other described embodiment of the invention. Certain features described in the context of various embodiments are not to be considered essential features of those embodiments, unless the embodiment is inoperative without those elements.

[0123] The contents of U.S. Patent Nos. cited in this application are hereby incorporated by reference, and shall not be construed as an admission that such reference is available as prior art to the present invention. All of the incorporated publications and patent applications in this specification are indicative of the level of ordinary skill in the art to which this invention pertains, and are incorporated to the same extent as if each individual publication or patent application was specifically indicated and individually indicated by reference.

[0124] Because the instant application is a continuation or divisional application, to the extent any amendments, characterizations, or other assertions previously made (in any related patent applications or patents, including any parent, sibling, or child) with respect to any art, prior or otherwise, could be construed as a disclaimer of any subject matter supported by the present disclosure of this application, Applicant hereby rescinds and retracts such disclaimer. Applicant also respectfully submits that any prior art previously considered in any related patent applications or patents, including any parent, sibling, or child, may need to be re-visited.