JP7356462B2 - Gas phase corrosion prevention - Google Patents

Description

The disclosed technology relates to corrosion protection of electrically conductive components that have been exposed to, but not immersed in, an automotive lubricant composition, or in other words, vapor phase corrosion protection. This technology relates more specifically to the use of azole compounds that can prevent corrosion of electrically conductive components in the vapor space above an automotive lubricant composition, and often also in the liquid phase of the lubricant composition. .

Corrosion is becoming increasingly relevant in the automotive industry due to the electrification of vehicle drivelines, whether fully electric, hybrid, or even internal combustion engines. Although transmission lubricants are designed to protect the surfaces of metals (most often copper or iron) that are immersed in the oil from corrosion, some lubricants can still be corrosive. be. Additionally, problems arise due to corrosion of parts that are not immersed in oil. For example, the evolution of transmissions has led to the increased use of sensors that are not immersed in lubricant, but are exposed to corrosive species in the vapor space. Because such electronic devices are typically not submerged in lubricant, these electronic devices are unprotected. Corrosion protection performance for non-immersion electronics is not currently included in vehicle lubricant specifications, but vapor-phase corrosion performance is becoming increasingly important, especially for sensitive electronics where even the slightest corrosion can interfere with the functionality of the electronics. expected to become important. Corrosion has been studied in the gas phase, but the corrosion phenomena described so far are mainly due to atmospheric corrosion (e.g. based on humidity, oxidation, and salts), whereas Corrosion associated with electronics in the upper headspace has a significantly different set of environmental factors (eg, low humidity, low oxygen, volatile lubricants, and lubricant degradation products).

A need exists to provide corrosion protection to electrically conductive components of a motor vehicle that have not been immersed in a protective lubricant composition. Thus, a need exists for vapor phase corrosion protection for electrically conductive components of vehicles.

It has been found that certain azole compounds that have vapor pressures high enough to escape the liquid phase of the lubricant composition can provide vapor phase corrosion protection above the lubricant composition.

Accordingly, the disclosed technology provides lubricant compositions containing azole compounds and methods of using the same that can prevent corrosion of electrically conductive components in the vapor space above the lubricant composition. Solving the problem of vapor phase corrosion of conductive components in vehicles.

The lubricant composition can include an oil of lubricating viscosity and an azole compound that can escape the lubricant composition and prevent corrosion in the vapor space above the lubricant composition.

In one embodiment, the azole compound can be a low molecular weight triazole or low molecular weight tetrazole compound. In some embodiments, the azole compound can be an N-substituted azole compound that decomposes to a low molecular weight triazole or low molecular weight tetrazole compound under automotive equipment operating conditions. In further embodiments, the azole compound can be an N-substituted azole compound that decomposes in the presence of a compound that reacts with the N-substituted azole compound to yield a low molecular weight triazole or low molecular weight tetrazole compound.

The lubricant composition can further include a compound that reacts with the N-substituted azole compound to produce a low molecular weight triazole or low molecular weight tetrazole compound.

In embodiments, the composition can further contain volatile compounds that are corrosive to electrically conductive components.

A method of lubricating a motor vehicle device having electrically conductive components is also provided. The method includes providing an automotive device having an electrically conductive component, a portion of which is dry, and then applying a lubricant composition as described above to the automotive device. and operating motor vehicle equipment.

Conductive components can include, for example, electrical wires, electrical sensors, printed circuit boards, or electric motors.

The electrically conductive component can contain, for example, copper or a copper alloy.

In embodiments, this method can be applied when the motor vehicle device contains a transmission, such as a dual clutch transmission, or a transmission driven by an electric motor.

In a further embodiment, the method can be applied when the motor vehicle device contains an axle. In some embodiments, the axle can be driven by an electric motor.

Various preferred features and embodiments are described below by way of non-limiting example.

One aspect of the present technology includes preventing corrosion of electrically conductive components in 1) oil of lubricating viscosity and 2) both in the liquid phase of the lubricant composition and in the vapor space above the lubricant composition. and 3) volatile compounds that are corrosive to conductive components.

Oil of Lubricating Viscosity One component of the disclosed technology is an oil of lubricating viscosity, also referred to as base oil. The base oil may be selected from any of the base oils of Groups IV of the American Petroleum Institute (API) Base Oil Compatibility Guidelines (2011), i.e.:

Groups I, II, and III are mineral oil based resources. Other commonly recognized categories of base oils may be used even if not officially identified by the API. Group II+ refers to Group II materials with a viscosity index of 110-119 and lower volatility than other Group II oils, and Group III+ refers to Group III materials with a viscosity index of 130 or higher. Oils of lubricating viscosity may include natural or synthetic oils and mixtures thereof. Mixtures of mineral oils and synthetic oils, such as polyalphaolefin oils and/or polyester oils, may also be used.

In one embodiment, the oil of lubricating viscosity is 2 to 7.5, or 10, or 3 to 6, or 3.25 to 6, or 3.5 to 5 mm ² /sec, or 2 to 7, or 3 to It has a kinematic viscosity at 100° C. according to ASTM D445 of 6, or 3 to 5. In one embodiment, the oil of lubricating viscosity comprises a polyalphaolefin having a kinematic viscosity at 100° C. according to ASTM D445 of 2 to 7.5, or any of the other aforementioned ranges.

Azole Compounds The lubricant composition also contains an azole compound that can prevent corrosion of electrically conductive components in the space above the lubricant composition.

The term "conductive component" is used to refer to a component in an automobile engine or driveline that conducts electricity, such as, for example, electrical wires, electrical sensors, printed circuit boards, electric motors, and the like. Although such components are generally kept "dry," meaning that they are not immersed in a lubricant composition, the components are often , in close proximity to and exposed to the lubricant composition. Such conductive components may be made of copper or other conductive materials, such as copper alloys (brass, bronze), silver, aluminum, gold, platinum, tin, and alloys of any of the foregoing, or other similar Can be prepared from electrically conductive materials.

Many azole compounds exhibit corrosion protection in the liquid phase of lubricant compositions. However, not all azole compounds exhibit corrosion protection in the vapor space above the lubricant composition. To exhibit such vapor phase corrosion protection, the azole compound must first have a sufficiently high vapor pressure to vaporize, that is, to escape from the liquid phase of the lubricant composition and enter the gas phase. Must be. The azole compound must not only escape from the liquid phase, but must also be able to coat the conductive components in order to protect them from other volatile compounds present in the gas phase. Otherwise, these other volatile compounds become corrosive to conductive components.

Without wishing to be bound by theory, the coating of the conductive component is based on the fact that the azole compound contains more nitrogen than the bicyclic ring and is available on the azole ring to interact with the metal of the conductive component. This can occur if it has protons. Thus, azole compounds that can prevent corrosion of electrically conductive components in the vapor space above the lubricant composition can include low molecular weight triazoles and low molecular weight tetrazoles. By low molecular weight is meant a compound having a molecular weight of about 50 to 350 Daltons, or about 55 to 250 Daltons, or about 60 to 150 or 200 Daltons. Such compounds include, for example, compounds of Formula I or Formula II.
R ₁ and R ₂ can individually be H or a C ₁ -C ₉ alkyl group.

Examples of azole compounds of Formula I can include, for example, 1,2,4-triazole, 3-methyl-1, and 2,4-triazole. Examples of Formula II can include, for example, 1H-tetrazole, 5-methyltetrazole, and the like.

Azole compounds capable of preventing corrosion of electrically conductive components can also include N-substituted azole compounds. N-substituted azole compounds may provide gas phase corrosion protection by themselves or may decompose under automotive equipment operating conditions to lower molecular weight triazole or lower molecular weight tetrazole compounds, or N-substituted The azole compound may decompose into a low molecular weight triazole or low molecular weight tetrazole in the presence of a compound that reacts with the compound (a "reactive compound"), resulting in the release or formation of a low molecular weight triazole or low molecular weight tetrazole compound.

Formula I and Formula II may be reacted with alkyl (meth)acrylates to obtain compounds with alkyl (meth)acrylate substituents on the ring nitrogen. For example, a formula may be reacted to obtain a formula with an amine substituent on the ring nitrogen by reacting with formaldehyde and the desired amine.

Exemplary N-substituted azole compounds with amine substituents can include 1,2,4 triazoles of Formula III:
Here, R ₃ and R ₄ are independently C ₁ -C ₂₂ , or C ₂ -C ₂₀ , or C ₃ -C ₁₈ , or C ₃ -C ₁₆ , or C ₁₂ , linear or branched. The two ends of any hydrocarbon group, phenyl group, or hydrocarbon chain forming a cyclic structure can be, or at least one of R ₃ and R ₄ can be H.

In some embodiments, the N-substituted azole compound can be an N-branched substituted 1,2,4 triazole, such as that of Formula III, where R ₃ and R ₄ are independently , C ₁ -C ₂₂ , or C ₂ -C ₂₀ , or C ₃ -C ₁₈ , or C ₃ -C ₁₆ , or C ₁₂ can be a branched hydrocarbon group, or two of the hydrocarbon chains The ends form a cyclic structure. Examples of structures of Formula III can include:

In some embodiments, the N-substituted azole compound can be an N-linear substituted 1,2,4 triazole, such as that of Formula III, where R ₃ and R ₄ are independently may be a straight chain C ₁ -C ₂₂ , or C ₂ -C ₂₀ , or C ₃ -C ₁₈ , or C ₃ -C ₁₆ , or C ₁₂ hydrocarbon group (including carbonyl group or acrylamide basis); can. Examples of structures of Formula III can include:

In other embodiments, the N-substituted azole compound can be an N-singly substituted 1,2,4 triazole, such as, for example, that of formula III, where R ₃ and R ₄ are independently can be a C ₁ -C ₂₂ , or C ₂ -C ₂₀ , or C ₃ -C ₁₈ , or C ₃ -C ₁₆ or C ₁₂ , straight chain or branched hydrocarbon group, or The two ends of the hydrocarbon chain form a cyclic structure, and at least one of R ₃ and R ₄ is H. Examples of structures of Formula III can include:

Azole compounds can also include N-substituted 1,2,4 triazoles, where the N substituent is in the 4-position, as in Formula IV:
where R ₃ and R ₄ are defined above. The compound of Formula IV may, in some embodiments, be naturally occurring impurities or minor isomers formed during the preparation of the compound of Formula III.

Other N-substituted azole compounds can include 1,2,3 triazoles of formula V.
R ₅ is independently C ₁ -C ₂₂ , or C ₂ -C ₂₀ , or C ₃ -C ₁₈ , or C ₃ -C ₁₆ , or C ₁₂ , a linear or branched hydrocarbon group, or a phenyl group. or the two ends of the hydrocarbon chain form a cyclic structure, and R ₆ and R ₇ are C ₁ -C ₄ , or C ₁ -C ₃ , or C _{1 -C2} , or at least one of _R5 , _R6 and _R7 can be H, or both _R6 and _R7 are H, or At least one of R ₅ , R ₆ and R ₇ can contain a carbonyl or acrylamide group, such as methyl propionate or ethylhexyl propionate, which can convert the azole compound into an acrylate, acrylic acid, acrylamide, or It may also be formed by contacting with a combination of these.

Additional N-substituted azole compounds include tetrazoles of formula VI:
Here, R ₈ and R ₉ are independently C ₁ -C ₂₂ , or C ₂ -C ₂₀ , or C ₃ -C ₁₈ , or C ₃ -C ₁₆ , or C ₁₂ , linear or branched. It can be either a hydrocarbon group, a phenyl group, or the two ends of the hydrocarbon chain form a cyclic structure, or at least one of R ₈ and R ₉ is H. can.

The azole compound is incorporated into the lubricant composition at a level sufficient to provide suitable corrosion protection in the gas phase during use. Generally, a level of about 30 ppm to 5% by weight of azole compound is suitable for most applications. In some embodiments, the azole compound is present at a level of from about 50 ppm to 4%, or from about 250 ppm to 3%, or from 500 ppm to 2%, or from 1000 ppm to 1000 ppm, based on the total weight of the lubricant composition. It can be incorporated at a level of 1% by weight. In some embodiments, the azole compound can be incorporated at a level of about 100 ppm to 5000 ppm, or 250 ppm to 2500 ppm, or 500 to 2000 ppm.

Azole Decomposition The azole compounds described above may be decomposed to provide low molecular weight azole compounds. Decomposition can occur, for example, due to temperatures occurring during operation of motor vehicle equipment.

Decomposition can also be caused by the presence of a compound (a "reactive compound") that reacts with the N-substituted azole compound resulting in the release or formation of a low molecular weight triazole or low molecular weight tetrazole compound. Accordingly, the lubricant composition can further include a compound that reacts with the N-substituted azole compound resulting in decomposition to a low molecular weight triazole or low molecular weight tetrazole compound.

In some embodiments, the reactive compound can be an electrophile, a nucleophile, or a combination thereof. Thus, the lubricant composition can also include a compound that is electrophilic to the azole compound and/or a compound that is nucleophilic to a substituent on the azole compound, or a combination thereof.

Electrophilic compounds may include, for example, Lewis acids and Bronsted acids. Examples of electrophilic compounds are, for example, hydrogen (whether by itself or as an "onium" compound such as _NH4 ⁺ or _H3O ⁺ ), Li+, Cu(I/II) , metal cations such as Ti(IV), Fe(II/III), trigonal planar species such as _BF3 , polar molecules such as α,β-unsaturated carbonyls, and carbon dioxide. Such compounds can originate in lubricants from other additives in the lubricant, such as detergent bases and antiwear additives and their decomposition products.

Nucleophilic compounds can include Lewis bases. Examples of nucleophiles can include iodine, alcohols such as methanol, ethanol or higher alcohols, ammonia, or amines such as those obtained from the head groups of dispersants or surfactants. Again, such compounds can arise in the lubricant from other additives in the lubricant, such as friction modifiers and their decomposition products.

Liquid Phase Corrosion Inhibitor The lubricant composition can also include a corrosion inhibitor that operates in the liquid to prevent corrosion in the liquid phase. An example of such a liquid phase corrosion inhibitor can include substituted thiadiazoles, such as, for example, dimercaptothiadiazole (DMTD) derivatives. DMTD derivatives may be used to prevent corrosion of copper. Dimercaptothiadiazole derivatives are typically soluble forms or derivatives of DMTD. Possible starting materials for the preparation of oil-soluble derivatives containing a dimercaptothiadiazole nucleus include 2,5-dimercapto-[1,3,4]-thiadiazole, 3,5-dimercapto-[1,2, 4]-thiadiazole, 3,4-dimercapto-[1,2,5]-thiadiazole, and 4,-5-dimercapto-[1,2,3]-thiadiazole. Of these, the most readily available is 2,5-dimercapto-[1,3,4]-thiadiazole. Various 2,5-bis-(hydrocarbondithio)-1,3,4-thiadiazoles and 2-hydrocarbyldithio-5-mercapto-[1,3,4]-thiadiazoles may be used. Hydrocarbon groups may be cyclic, cycloaliphatic, aliphatic or aromatic, including aralkyl, aryl and alkaryl. Similarly, the condensation product of an α-halogenated aliphatic monocarboxylic acid with DMTD, or by reacting DMTD with an aldehyde and a diarylamine in a molar ratio of from about 1:1:1 to about 1:4:4. Similar to the resulting products, carboxylic acid esters of DMTD are known and can be used. DMTD materials may also exist as salts, such as amine salts. In other embodiments, the DMTD compound may be the reaction product of an alkylphenol and an aldehyde, such as formaldehyde, and dimercaptothiadiazole. Another useful DMTD derivative is obtained by reacting DMTD with an oil-soluble dispersant such as a succinimide dispersant or a succinate ester dispersant.

When present, the amount of DMTD compound may range from 0.01 to 5 percent by weight of the composition, such as from 0.01 to 1 percent, or from 0.02 to 0.5 percent, depending in part on the identity of the particular compound. 4, or 0.03 to 0.1 weight percent. Alternatively, if DMTD is reacted with a nitrogen-containing dispersant, the total weight of the combined product can be significantly higher to impart the same active DMTD chemistry, e.g., 0.1 to 5 weight percent, or 0.2-2 or 0.3-1 or 0.4-0.6 weight percent.

In some embodiments, the substituted thiadiazole is substantially free or free of reactants that can react with the substituted thiadiazole to form a volatile corrosive thiol, such as, for example, disodium hydrogen phosphite. may be present in the formulation.

Volatile Corrosive Compounds The lubricant composition also includes volatile compounds that are corrosive to electrically conductive components, or "volatile corrosive compounds" for short, depending on the description of the problem. Volatile substances related to volatile corrosive compounds have the same meaning as azole compounds. That is, the volatile corrosive compound must have a vapor pressure high enough to vaporize, ie, escape from and enter the gas phase of the lubricant composition under vehicle operating conditions.

Volatile corrosive compounds can be compounds added to lubricant compositions intended for, for example, bulk phase rust protection, friction modification, or other bulk fluid purposes such as wear and oxidation protection. . Volatile corrosive compounds can also be generated in situ, for example, as natural decomposition products of components of a lubricant composition or from the reaction of two or more components in a lubricant composition.

In one embodiment, the volatile corrosive compound can be a volatile sulfur-containing compound, such as a thiol. Other sulfur-containing compounds that can cause corrosion include, for example, sulfurized olefins, disulfides, sulfurized esters, mercaptans, thioethers, dialkyldithiophosphoric acids and their salts, and dithiocarbamates.

Volatile corrosive compounds can also include hydrogen sulfide resulting from the decomposition or hydrolysis of any sulfur-containing compounds. Similarly, volatile corrosive compounds can be low molecular weight mercaptans resulting from the decomposition of sulfurized olefins, or sulfur dioxide compounds resulting from the thermal decomposition of sulfonates or sulfones. In one embodiment, the volatile corrosive compound can be the reaction product of a substituted thiadiazole and hydrogen phosphite.

Methods of Vapor Phase Corrosion Prevention Further aspects of the present technology include methods of lubricating automotive equipment having electrically conductive components. The method includes providing a motor vehicle device including a conductive component in which a portion of the conductive component is dry (ie, not immersed in a lubricant composition). A lubricant composition as disclosed above can be supplied to a motor vehicle device and the motor vehicle device is operated.

The automotive device, in one embodiment, is a driveline device. The driveline device can be, for example, a gear, an axle, a driveshaft, an automatic or manual transmission, or the driveline of an off-highway vehicle (such as a farm tractor). Such driveline equipment is lubricated by gear oil, axle oil, driveshaft oil, traction oil, manual transmission oil, automatic transmission oil, or off-highway oil (such as farm tractor oil).

In one embodiment, a method is provided for lubricating a manual transmission that may or may not include a synchronizer system. In one embodiment, a method of lubricating an automatic transmission is provided. In one embodiment, the invention provides a method of lubricating an axle.

Automatic transmissions that may be encompassed by the disclosed method include, for example, continuously variable transmissions (CVTs), infinitely variable transmissions (IVTs), toroidal transmissions, continuously slipping torque converter clutches (CSTCCs), stepped automatic transmissions, or Includes dual clutch transmission (DCT).

Automatic transmissions may include a continuous slipping torque converter clutch (CSTCC), a wet start, and a shift clutch, and may optionally contain a metal or composite synchronizer. Dual clutch transmissions or automatic transmissions may incorporate an electric motor unit.

With respect to axles and gears, the method includes applying gear oil or axle oil in planetary hub reduction axles, mechanical steering and transfer gearboxes in utility vehicles, synchromesh gearboxes, power take-off gears, limited slip axles, and planetary hub reduction gearboxes. This may include hiring. The axle may incorporate an electric motor unit. The motor may be placed, for example, "in-wheel" or on the front or rear axle. Electric motors may also be integrated into the drive shaft.

The amounts of each chemical component listed are stated on an active chemical basis, exclusive of any solvents or diluent oils that may normally be present in commercially available materials, unless otherwise indicated. However, unless otherwise indicated, each chemical entity or composition referred to herein contains isomers, by-products, derivatives, and other such materials commonly understood to be present in commercial grade. It should be construed to be commercial grade material.

It is known that some of the above substances may interact in the final formulation, so the ingredients of the final formulation may differ from those initially added. For example, metal ions may be transferred to other acidic or anionic sites on other molecules. Products formed thereby, including those formed by employing the compositions of the present invention in their intended applications, may not be easily described. Nevertheless, all such modifications and reaction products are included within the scope of this invention, which encompasses compositions prepared by mixing the components described above.

As used herein, the term "about" means that the value of a given quantity is within ±20% of the stated value. In other embodiments, the value is within ±15% of the stated value. In other embodiments, the value is within ±10% of the stated value. In other embodiments, the value is within ±5% of the stated value. In other embodiments, the value is within ±2.5% of the stated value. In other embodiments, the value is within ±1% of the stated value.

The invention herein is useful in preventing corrosion of non-submerged conductive components in lubricated driveline equipment, which can be better understood with reference to the following examples.

Sample Preparation - General procedure for coupling an azole to an alkylamine with paraformaldehyde: 1.0 mole of azole is combined with 1.0 mole of alkylamine or dialkylamine and the mixture is heated to 60-80°C with stirring. do. Then 0.94 to 1.0 equivalents of paraformaldehyde are added. For low molecular weight amines, the paraformaldehyde charge is split into two equal parts and the second part is not charged until the reaction exotherm from ^{the first charge} has subsided. The equivalent weight of paraformaldehyde is calculated as follows.
Eq wt=30.0264/(wt% _CH2 =O in paraformaldehyde)
Once the exotherm due to paraformaldehyde addition has subsided, continue heating until all solids are dissolved. A vacuum is then applied to the reaction mixture to remove by-product water produced by the reaction. There is no need for further purification of the product. A sample prepared using this method is shown below.

Sample 1: A commercial sample of 1,2,4-triazole was purchased from Okyo Chemical Industry Company. Obtained from Ltd.

Sample 2: 1,2,4-triazole (0.81 mol) was reacted with piperidine (0.81 mol) and 91% paraformaldehyde (0.761 eq) according to the general procedure to give 131.66 g ( A clear, slightly yellow liquid was obtained (98% yield). The liquid froze upon cooling. The melting point of the product, 1-((1H-1,2,4-triazol-1-yl)methyl)piperidine, was 61-63°C. ¹ H and ¹³ C NMR of the product showed it to be very pure.

Sample 3: 1,2,4-triazole (0.746 mol) was reacted with diisopropylamine (0.738 mol) and 91% paraformaldehyde (0.701 eq) according to the general procedure to give 105.13 g A clear, faintly yellow liquid was obtained (77% yield). ¹ H and ¹³ C NMR of the product showed it to be impure. The primary impurity was di(1H-1,2,4-triazol-1-yl)methane, the product of unreacted 1,2,4-triazole and 2 moles of triazole coupled with formaldehyde. Ta.

Sample 4: 1,2,4-triazole (0.653 mol) was reacted with dibutylamine (0.654 mol) and 91% paraformaldehyde (0.614 eq) according to the general procedure to give 131.64 g A clear colorless liquid was obtained (96% yield). The product, N,N-dibutyl-1H-1,2,4-triazole-1-methanamine, was essentially pure by ¹ H and ¹³ C NMR.

Sample 5: 1,2,4,-triazole (0.654 mol) was reacted with diisobutylamine (0.654 mol) and 91% paraformaldehyde (0.615 eq.) according to the general procedure to give 131. 68 g (96% yield) of a colorless, low-melting crystalline solid, N,N-diisobutyl-1H-1,2,4-triazole-1-methanamine, with a melting point of <45° C., was obtained. The product was essentially pure by ¹ H and ¹³ C NMR, with the only impurities being traces of triazole and triazole binding compounds.

Sample 6: 1,2,4-triazole (0.653 mol) was reacted with 2-ethylhexylamine (0.654 mol) and 91% paraformaldehyde (0.615 eq) according to the general procedure, 131. 48 g (96% yield) of a clear, nearly colorless liquid was obtained. However, ¹ H and ¹³ C NMR spectra indicate that the desired product, N-((1H-1,2,4-triazol-1-yl)methyl)-2-ethylhexan-1-amine, is in high purity. showed that it was not obtained. The NMR spectrum shows that the product obtained contained a mixture of at least three compounds in addition to the desired compound.

Sample 7: 1,2,4-triazole (0.534 mol) was reacted with dicyclohexylamine (0.533 mol) and 91% paraformaldehyde (0.501 eq.) according to the general procedure to give 139.07 g ( An almost colorless crystalline solid, N,N-dicyclohexyl-1H-1,2,4-triazole-1-methanamine, with a melting point of >65° C. was obtained in a yield of 99.5%. The product showed good purity by ¹ H and ¹³ C NMR. The only impurities were trace amounts of triazole and triazole bonding compounds and unreacted triazole.

Sample 8a: BASF Corporation's commercially available corrosion inhibitor Irgamet® 30, CAS number 91273-04-0, is a formaldehyde combined product of 1,2,4-triazole and bis(2-ethylhexyl)amine. ¹ H and ¹³ C NMR spectra of this sample show that it is very pure.

Sample 8b: A product similar to Irgamet30 was prepared using the general procedure. 1,2,4-triazole (0.439 mol) was reacted with bis(2-ethylhexyl)amine (0.440 mol) and 91% paraformaldehyde (0.411 eq.) to give 142.71 g (100% ) A clear colorless liquid product was obtained. 1H and 13C NMR spectra of this material showed purity comparable to the commercial product of Sample 8a.

Sample 9: 1,2,4-triazole (0.404 mol) was reacted with oleylamine (0.404 mol) and 91% paraformaldehyde (0.403 eq) according to the general procedure to give 141.79 g ( A waxy product with a yield of 99.8% was obtained. ¹ H and ¹³ C NMR spectra showed the product to be a mixture of several compounds.

Sample 10: 1,2,4-triazole (0.313 mol) was reacted with ditridecylamine (0.312 mol) and 95% paraformaldehyde (0.313 eq.) according to the general procedure, giving 144.26 g (100% yield) of a clear, almost colorless liquid product was obtained. Ditridecylamine used in this sample was obtained from BASF. It is a complex mixture of isomers. ¹ H and ¹³ C NMR spectra confirm that the product is a complex mixture.

Sample 11: 1,2,4-triazole (0.315 mol) was reacted with dicocoamine (0.316 mol) and 95% paraformaldehyde (0.314 eq) according to the general procedure to give 142.15 g ( A clear, light amber liquid product was obtained (98.9% yield). The alkyl groups on dicocoamine are primarily a mixture of saturated C ₁₂ -C ₁₄ straight hydrocarbon chains. ¹ H and ¹³ C NMR show that the product is very pure.

Sample 12: A commercial sample of 5-methyltetrazole is available from Tokyo Chemical Industry Company. Obtained from Ltd.

Sample 13: 5-methyltetrazole (0.490 mol) and bis(2-ethylhexyl)amine (0.494 mol) combined with 91% paraformaldehyde (0.458 mol) using the general procedure This gave 165.75 g (99.4%) of a clear, nearly colorless liquid product. ¹ H NMR spectrum shows that the product is very pure. However, because there is no direct hydrogen atom on the azole ring, it could not be definitively said whether the formaldehyde-bonded substituent was attached to N1 or N2 of the ring. However, NMR shows a single ring of methyl groups, indicating that only one of the two possible substitution isomers was formed.

Sample 14: 5-phenyltetrazole (0.358 mol) and bis(2-ethylhexyl)amine (0.359 mol) were combined with 91% paraformaldehyde (0.336 mol) using the general procedure. , 142.81 g (99.2%) of a clear, almost colorless liquid product was obtained. ¹ H NMR spectrum shows that the product is very pure. The position of the formaldehyde-bonded substituent on the ring is not critical, but a single positional isomer is observed in the spectrum.

Sample 15: A commercial sample of 1,2-dimethylimidazole was obtained from Alfa Aesar.

Sample 16: A commercial sample of 2,4-dimethylimidazole was obtained from Alfa Aesar.

Sample 17: A commercial sample of 1-butylimidazole was obtained from Alfa Aesar.

Sample 18: A commercial sample of 1-methyl-1,2,4-triazole was obtained from Alfa Aesar.

Sample 19: Skosanor KSP-93, a commercially available oil-soluble corrosion inhibitor, was obtained from Lubrizol Corporation. This product is the reaction product of tolyltriazole, bis(2-ethylhexyl)amine, and paraformaldehyde, as shown below.

Formulation A for Testing Gas Phase Corrosion: The formulation shown below, representative of a typical automotive transmission fluid, has two known copper corrosion inhibitors (indicated by an asterisk "*"). Nevertheless, severe vapor phase corrosion of copper occurs within a few days at 65°C. In some of the tests described below, Formulation A without tolyltriazole is used.

Semi-immersion test: Formulation A is top treated with the sample vapor phase corrosion inhibitor above at the reported processing rate. The freshly polished copper strips are half immersed in the top treated fluid in a 4 ounce jar that is capped and placed in a temperature controlled oven. Corrosion of both the immersion and vapor space portions of the coupon is evaluated following the ASTM D130 rating scale after a specified period of time. In each test, a blank (Formulation A without top treatment) is used as a standard.

Example 1: Several sample corrosion inhibitors were incorporated into Formulation A without tolyltriazole at a level of 500 ppm (listed as "Baseline" in Table 1). A semi-immersion test was conducted for each of these fluids at 65° C. for 7 days. The ASTM D130 ratings for both the liquid and vapor space portions of each coupon are shown in Table 1 below.

Example 2: The performance of three sample corrosion inhibitors in a semi-immersion test for the treatment level of Formulation A without tolyltriazole is shown in Table 2. The semi-immersion test was conducted at 80°C for 7 days. ASTM D130 ratings are listed for both liquid and vapor spaces (front side only).

Example 3: Sample corrosion inhibitor performance was demonstrated in both low and high viscosity fluids. All three formulations contained additives with the same performance as Formulation A, except for the base oil and viscosity modifier. The base oil of Example 3a was a 2 cSt polyalphaolefin, the base oil of Example 3b was a low viscosity petroleum alkylate, and the base oil of Example 3c was an 8 cSt polyalphaolefin. None of these formulations contained polymeric viscosity modifiers.

Example 4: The performance of the sample corrosion inhibitor was also demonstrated in alternative fluids. Formulation B is a gear oil formulation containing the additives listed below.

Formulation B was top-treated with 500 ppm Sample 8a in one example and 500 ppm Sample 19 in another example. These top treated gear oil formulations were subjected to a 7 day semi-soak test at 80°C. The results are listed in Table 4.

Example 5: This semi-soak test is a short term comparison of several low molecular weight azoles in Formulation A without tolyltriazole. The test was conducted at 80°C for 24 hours. Each sample was added to Formulation A as a 1000 ppm top treatment.

Example 6: A 4 ounce uncovered jar of Formulation A was placed into a 1/2 gallon wide mouth jar. A freshly polished copper coupon was placed on top of a small jar to avoid contact with the liquid. The large outer jar was capped and the entire assembly was placed in an 80°C oven for 2 days. The coupon turned black (4C rating). This test demonstrated that the corrosive species from Formulation A were acting by volatilization of the corrosive species into the vapor space, rather than by a mechanism in which the corrosive species rose up the surface of the coupon from the liquid phase. There is.

Example 7: Two 4 ounce uncovered jars of Formulation A, topped with 1000 ppm of Sample 8, were placed inside a 1/2 gallon wide mouth jar. A freshly polished copper coupon was placed on top of a small jar to avoid contact with the liquid. The large outer jar was capped and the entire assembly was placed in an 80°C oven for 2 days. The coupon remained in its original condition (1A rating). This test, related to Example 6, demonstrated that the vapor space inhibiting species from top-treated Formulation A acted by volatilization into the vapor space rather than by a mechanism in which the inhibiting species rose up the surface of the coupon from the liquid phase. It proves that there is. This test also excludes mechanisms where the corrosion-inhibiting species reacts with or neutralizes the corrosive species in the liquid phase before it can volatilize.

Example 8: One 4 oz uncovered jar of Formulation A and a second 4 oz uncovered jar of 4 cSt Group III oil top treated with 1000 ppm Sample 8 were added to 1/4 oz. Placed in a 2 gallon wide mouth jar. Anhydrous calcium sulfate pellets were also scattered on the bottom of the 1/2 gallon jar to maintain an anhydrous environment inside the jar. A freshly polished copper coupon was placed on top of a small jar to avoid contact with the liquid. The outer large jar was purged with nitrogen, then capped and the entire assembly placed in an 80° C. oven for 6 days. The coupon slowly turned black (4 rating). This test in conjunction with Examples 6 and 7 demonstrates that Sample 8 is essentially unable to provide vapor space corrosion protection.

Example 9: Performance of the sample corrosion inhibitor was also demonstrated in alternative fluids. Formulation C represents the baseline manual transmission fluid.

Fluids EK were produced by adding thiadiazole corrosion inhibitor and/or sample 8b of the invention to Formulation C. Each fluid was tested and evaluated according to ASTM D130 at 121°C and 150°C for 3 hours, and underwent a half-immersion test at 80°C for 168 hours. The results are shown below.

Each of the documents mentioned above is herein incorporated by reference, including any prior applications from which priority is claimed, whether or not specifically listed above. Reference to any document is not an admission that such document qualifies as prior art or constitutes the general knowledge of those skilled in the art in any capacity. Except in the Examples or unless otherwise expressly indicated, all quantities in this description specifying amounts of materials, reaction conditions, molecular weight, number of carbon atoms, etc. are modified by the word "about." I want to be understood as something that is done. It is to be understood that the upper and lower amount, range, and ratio limits set forth herein can be independently combined. Similarly, the ranges and amounts for each element of the invention can be used in conjunction with the ranges or amounts for any of the other elements.

As used herein, the transitional term "comprising" is synonymous with "including," "containing," or "characterized by." , is inclusive or unlimited and does not exclude additional, unlisted elements or method steps. However, in each recitation of "comprising" herein, the term also includes, as alternative embodiments, the phrases "consisting essentially of" and "consisting of." is intended to include, where "consisting of" excludes any element or step not specified, and "consisting essentially of" means excluding any element or step not specified. It is permissible to include additional unlisted elements or steps that do not substantially affect the essential or fundamental and novel characteristics of the composition or method being described.

Although certain representative embodiments and details have been shown for the purpose of illustrating the subject invention, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the scope of the subject invention. Will. In this regard, the scope of the invention is intended to be limited only by the following claims.
The present invention provides, for example, the following items.
(Item 1)
1. A method of lubricating a motor vehicle device having electrically conductive components, the method comprising:
a. Provided is an automotive device including an electrically conductive component, a portion of the component being dry;
b. In the automobile device,
i. oil of lubricating viscosity,
ii. providing the lubricant composition comprising an azole compound capable of preventing corrosion of the electrically conductive components in the vapor space above the lubricant composition;
c. driving the motor vehicle device.
(Item 2)
2. The method of item 1, wherein the electrically conductive component includes an electrical wire, an electrical sensor, a printed circuit board, an electric motor.
(Item 3)
3. A method according to item 1 or 2, wherein the electrically conductive component comprises copper or a copper alloy.
(Item 4)
The azole compound may be a low molecular weight triazole or low molecular weight tetrazole compound; an N-substituted azole compound that decomposes under the operating conditions of the automotive device into a low molecular weight triazole or low molecular weight tetrazole compound; or The method according to item 1 or 2 or 3, comprising an N-substituted azole compound that decomposes in the presence of a compound that decomposes into a low molecular weight triazole or low molecular weight tetrazole compound.
(Item 5)
The azole compound is an N-substituted 1,2,4 triazole

including;
Here, R ₁ and R ₂ are either linear or branched, or a C3-C22 hydrocarbon group in which the two ends of the hydrocarbon chain form a cyclic structure, or R 1 _or R ₂ The method according to item 1 or 2 or 3 or 4, wherein one of is H.
(Item 6)
as described in item 1 or 2 or 3 or 4 or 5, wherein the N-substituted 1,2,4 triazole comprises N,N-bis(2-ethylhexyl)-1H-1,2,4 triazole-1-methanamine the method of.
(Item 7)
The azole compound includes an azole-acrylic adduct formed by contacting an azole compound with an acrylate ester, acrylic acid, acrylamide, or a combination thereof, wherein the adduct contains at least one acyl group. 5. A method according to item 1 or 2 or 3 or 4, having two nitrogen-alkyl groups.
(Item 8)
8. The method of item 1 or 2 or 3 or 4 or 5 or 6 or 7, wherein the lubricant composition further comprises a volatile compound corrosive to the electrically conductive component.
(Item 9)
9. The method of item 8, wherein the volatile compound corrosive to the electrically conductive component comprises a volatile sulfur-containing compound.
(Item 10)
9. The method of item 8, wherein the source of volatile sulfur comprises a thiol or a reaction product of a substituted thiadiazole and hydrogen phosphite.
(Item 11)
11. The method of item 1 or 2 or 3 or 4 or 5 or 6 or 7 or 8 or 9 or 10, wherein the motor vehicle device includes a transmission.
(Item 12)
12. The method of item 11, wherein the transmission is a dual clutch transmission.
(Item 13)
12. The method of item 11, wherein the transmission is driven by an electric motor.
(Item 14)
11. The method of item 1 or 2 or 3 or 4 or 5 or 6 or 7 or 8 or 9 or 10, wherein the motor vehicle device comprises an axle.
(Item 15)
15. The method of item 14, wherein the axle is driven by an electric motor.
(Item 16)
16. The method of any of items 1-15, further comprising a thiadiazole corrosion inhibitor in the absence of phosphite.
(Item 17)
A lubricant composition comprising:
a. oil of lubricating viscosity;
b. an azole compound capable of escaping the lubricant composition and preventing corrosion in the space above the lubricant composition.
(Item 18)
The azole compound may be a low molecular weight triazole or low molecular weight tetrazole compound; an N-substituted azole compound that decomposes to a low molecular weight triazole or low molecular weight tetrazole compound under the operating conditions of automotive equipment; or 18. The composition of item 17, comprising an N-substituted azole compound that decomposes in the presence of a compound that decomposes to a low molecular weight triazole or low molecular weight tetrazole compound.
(Item 19)
The azole compound is an N-substituted 1,2,4 triazole,

including;
Here, R ₁ and R ₂ are either linear or branched, or are C3-C22 hydrocarbon groups in which the two ends of the hydrocarbon chain form a cyclic structure, or R 1 _or R ₂ The composition according to item 17 or 18, wherein one of the is H.
(Item 20)
The composition according to item 17 or 18 or 19, wherein the N-substituted 1,2,4 triazole comprises N,N-bis(2-ethylhexyl)-1H-1,2,4-triazole-1-methanamine .
(Item 21)
The azole compound includes an azole-acrylic adduct formed by contacting an azole compound with an acrylate, acrylic acid, acrylamide, or a combination thereof, the adduct containing at least one acyl group. Composition according to item 17 or 18, having a nitrogen-alkyl group.
(Item 22)
The composition according to item 17 or 18 or 19 or 20 or 21, further comprising a compound that is electrophilic towards the azole compound.
(Item 23)
The composition according to item 17 or 18 or 19 or 20 or 21 or 22, further comprising a compound that is nucleophilic to the substituent in the azole compound.
(Item 24)
The composition according to item 17 or 18 or 19 or 20 or 21 or 22 or 23, further comprising a volatile compound corrosive to the electrically conductive component.
(Item 25)
25. The composition of item 24, wherein the volatile compound corrosive to the electrically conductive component comprises a volatile sulfur-containing compound.
(Item 26)
26. The composition of item 24 or 25, wherein the source of volatile sulfur comprises a sulfurized olefin, a thiol, such as one formed from the reaction product of a substituted thiadiazole and hydrogen phosphite, or a combination thereof.
(Item 27)
27. The composition according to any of items 17-26, further comprising a thiadiazole corrosion inhibitor in the absence of phosphites.

Claims (18)

A method for preventing corrosion of electrically conductive components in a vapor space above a lubricant composition, the method comprising:
a. providing an automotive device including the electrically conductive component, a portion of the component being dry;
b. In the automobile device,
i. oil of lubricating viscosity,
ii. an azole compound capable of preventing corrosion of the electrically conductive components in the vapor space above the lubricant composition, the azole compound comprising:
1. N-substituted 1,2,4 triazole
(wherein R ₁ and R ₂ are either linear or branched, or a C3-C22 hydrocarbon group in which the two ends of the hydrocarbon chain form a cyclic structure, or R ₁ or R one of ₂ is H), or 2. including azole-acrylic adducts formed by contacting an azole compound with an acrylate ester, acrylic acid, acrylamide, or a combination thereof, wherein the adduct has at least one nitrogen-alkyl group containing at least one acyl group. has,
providing the lubricant composition comprising an azole compound;
c. driving the motor vehicle device. 2. The method of claim 1, wherein the electrically conductive component includes an electrical wire, an electrical sensor, a printed circuit board, or an electric motor. 3. A method according to claim 1 or 2, wherein the electrically conductive component comprises copper or a copper alloy. 4. The method of claim 1 or 2 or 3, wherein the N-substituted 1,2,4 triazole comprises N,N-bis(2-ethylhexyl)-1H-1,2,4-triazole-1-methanamine. . 4. The method of claim 1 or 2 or 3, wherein the lubricant composition further comprises a volatile compound corrosive to the electrically conductive component. 6. The method of claim 5, wherein the volatile compound corrosive to the electrically conductive component comprises a volatile sulfur-containing compound. 6. The method of claim 5, wherein the source of volatile sulfur comprises a thiol or a reaction product of a substituted thiadiazole and hydrogen phosphite. 8. The method of claim 1 or 2 or 3 or 4 or 5 or 6 or 7, wherein the motor vehicle device comprises a transmission. 9. The method of claim 8, wherein the transmission is a dual clutch transmission. 9. The method of claim 8, wherein the transmission is driven by an electric motor. 8. The method of claim 1 or 2 or 3 or 4 or 5 or 6 or 7, wherein the motor vehicle device comprises an axle. 12. The method of claim 11, wherein the axle is driven by an electric motor. A method according to any of claims 1 to 12, further comprising a thiadiazole corrosion inhibitor in the absence of phosphite. A lubricant composition comprising:
a. oil of lubricating viscosity;
b. an azole compound capable of escaping the lubricant composition and preventing corrosion in the space above the lubricant composition, the azole compound comprising :
N -substituted 1,2,4 triazole,
1. N,N-bis(1-methylethyl)-1H-1,2,4-triazole-1-methanamine; N,N-diisobutyl-1H-1,2,4-triazole-1-methanamine; N,N- Dicyclohexyl-1H-1,2,4-triazole-1-methanamine; 1-((1H-1,2,4-triazol-1-yl)methyl)piperidine; and N,N-bis(tridecyl)-1H- N-branched substituted 1,2,4 triazoles selected from mixed branched isomers of 1,2,4-triazole-1-methanamine;
2. N-linear substituted 1,2,4 triazole,
3. N-single substituted 1,2,4 triazole,
4. N-substituted 1,2,4 triazoles selected from N-substituted 1,2,4 triazoles in which the N-substituent is in the 4-position
an azole compound containing ;
c. and at least one of a Lewis acid, a Brønsted acid, or a Lewis base. 15. The composition of claim 14, further comprising a volatile compound corrosive to electrically conductive components. 16. The composition of claim 15, wherein the volatile compound corrosive to electrically conductive components comprises a volatile sulfur-containing compound. 17. The composition of claim 15 or 16, wherein the source of volatile sulfur comprises a sulfurized olefin, a thiol, such as one formed from the reaction product of a substituted thiadiazole and hydrogen phosphite, or a combination thereof. A composition according to any of claims 14 to 17, further comprising a thiadiazole corrosion inhibitor in the absence of phosphites.