JPH0245679B2 - HIDOROKARUBIRUKOHAKUSANMATAHAMUSUIBUTSUTOCHIOBISUARUKANOORUTONOESUTERUOYOBISONOKINZOKUENOGANJUSURUJIDOHENSOKUKIEKI - Google Patents

Description

[Detailed description of the invention]

The present invention provides automatic transmission fluids (ATFs) containing mono- and/or diesters of thiobisalkanols and hydrocarbyl-substituted succinic acids or anhydrides or metal salts thereof as friction modifiers, corrosion inhibitors and oxidation inhibitors. Regarding. The prior art discloses various compounds useful for friction modification in lubricating oils and ATF. As representative disclosures, U.S. Pat. No. 3,933,659 discloses fatty acid esters and amides as friction modifiers for functional fluids, and U.S. Pat. No. 4,176,074 discloses polyisobutenylsuccinic anhydride-aminoalkanols as friction modifiers. and US Pat. No. 4,105,571 discloses glycerol esters of dimerized fatty acids as friction modifiers in lubricating oils. US Patent No. 2,561,232 discloses diesters of monohydric alcohols (including those with sulfur bridges) esterified with _C3 - _C24 alkenylsuccinic acids. The diester disclosed herein is
It is said to be useful as a synthetic lubricant liquid.
U.S. Pat. No. 3,198,737 and U.S. Pat. No. 3,278,566 disclose fatty acid esters of thioglycols and other diols useful as intermediates in the production of polysulfoxyl esters that have use as extreme pressure additives. U.S. Pat. No. 2,540,570 discloses glycol esters of rosin or other fatty acids with thioglycols and states that the compounds are useful as extreme pressure additives. U.S. Pat. Nos. 3,045,042 and 3,117,091 disclose that partial esters of alkenyl succinic anhydrides, such as octadecenyl, with various polyhydric alcohols, including 2,2'-thiodiethanol, can be used in various applications, including mineral lubricating oils. The present invention discloses that it is useful as a rust-inhibiting compound for petroleum products. The term "rust" is used in reference to damage to metal caused by water. The prior art is known to reduce friction in ATF or hydraulic fluids, and at the same time to act as a corrosion inhibitor, particularly as a copper and brass corrosion inhibitor in ATF, and as a solder joint corrosion inhibitor in ATF cooling systems. , does not teach the use of mono- or diesters of alkenylsuccinic anhydrides and thiobisalkanols. According to the invention, mineral oil of lubricating viscosity and the formula [In the formula, R ₁ is hydrogen and

0.05 to 2 weights of a mono- or diester friction modifier selected from the group consisting of the formula: wherein x is a number 1 or 2 and R is octadecyl or octadecenyl or a mixture of said esters. % is provided. Such a substance has the formula (a) [wherein R and R' may each independently be hydrogen, methyl or ethyl, x may be 1 to 4, and a, b, c and d may each independently be 1 to 3; and (b) 1 to 1 mole of the thiobisalkanol.
can be formed by reaction with 2 moles of aliphatic hydrocarbon-substituted succinic acid or anhydride or mixtures thereof, where the aliphatic hydrocarbon group contains from 12 to 50 carbon atoms. . The term "monoester" or "half ester" as used herein means a product made from equimolar proportions of thiobisalkanol and succinic acid or anhydride, i.e. one free hydroxyl group remains. In contrast, the term "diester" refers to such products in which each hydroxyl group of a thiobisalkanol is esterified with a hydrocarbyl-substituted or polyolefin-substituted succinic acid or anhydride. In either case, the succinic moiety, the -C(O)OH group, remains, but this can be neutralized with metals or amines as described below to form useful salt derivatives. be able to. Hydrocarbylsuccinic acids or anhydrides per se are known in the art, and commonly used anhydrides have the formula [wherein R'' is a _C12 - _C50 aliphatic hydrocarbon group such as an alkyl, alkenyl, isoalkyl, isoalkenyl or cycloalkylhydrocarbyl group].As an aliphatic hydrocarbyl group, , oligomers containing from 12 to 50 carbon atoms, such as isobutene
Oligomers of _C2 - _C5 monoolefins are also suitable. The aliphatic hydrocarbyl group may be an unsubstituted hydrocarbon group or it may contain substituents such as chlorine, bromine, sulfur, phosphorus, nitrogen or oxygen that do not affect the utility of the final mono- or diester product. You can also do that. A preferred substituent is sulfur as exemplified by 2-octadecylthiosuccinic anhydride. These compounds can be prepared by the reaction of maleic anhydride with olefins, polyolefin oligomers or chlorinated derivatives thereof using techniques known in the art. Succinic acid is easily prepared by hydrolysis of the corresponding anhydride. Particularly preferred in preparing the mono- and diester compounds are _C18 - _C22 alkenyl succinic anhydrides, such as octadecenyl succinic anhydride. The term "thiobisalkanol" as used herein refers to the formula [wherein R and R' may each independently be hydrogen, methyl or ethyl, x may be 1 to 4, and a, b, c and d may each independently be 1 to 3; represents an ester-forming diol compound. If b or d is greater than 1, the formula represents an ethoxylated derivative of such alcohol. Preferred specific examples include a, b, c in the above formula.
and d are each 1 or 2 and R is H or CH ₃ . Specific compounds include 2,2'-dithiodiethanol, 2,2'-thiodiethanol, di(2
-hydroxypropyl) disulfide and 3,
3'-thiodipropanol is mentioned. The production of mono- and diesters is accomplished by reacting predetermined amounts of anhydride (or acid) and thiobisalkanol in the presence or absence of an inert organic solvent diluent and converting the mixture to the ester of the anhydride at about 50-150°C. The reaction proceeds by heating and stirring until completion. Equimolar amounts of each reactant provide primarily mono-(or half-)esters;
The reaction of two moles of hydrocarbon substituted succinic acid or anhydride per mole of thiobisalkanol then provides the diester material. In terms of yield, the reaction of equimolar ratios of thiobisalkanol and hydrocarbon succinic anhydride yields
A product containing about 80% monoester and about 20% diester is provided. When the molar ratio of succinic anhydride to thiobisalkanol is 2:1, diesters are produced in somewhat higher yields, ie, about 90% of the product is diester and about 10% monoester. Diester compounds are particularly preferred and generally exhibit good thermal and oxidative stability and provide good friction reducing properties. In the case of diester compounds, it is preferable to use succinic anhydride with hydrocarbon substituents smaller than C _{12, as long as the total number of carbon atoms of the hydrocarbon substituents on the succinic part of the ester compound is at least C 12 .} suitable. This is because the oil solubility of the final compound is an important property. The invention thus encompasses the use of symmetric diesters based on e.g. 2 moles of decenylsuccinic anhydride or asymmetric diesters based on 1 mole of _C3 hydrocarbon-substituted succinic anhydride and _C16 hydrocarbon-substituted succinic anhydride. do. Still other embodiments of the invention include boronated derivatives of monoester compounds and either mono- or diesters formed by reaction with free succinic acid moieties present on either the mono- or diester. A composition containing a metal and an amine salt. Boronated derivatives are based on the reaction of monoesters with free hydroxyl groups, and boronation processing techniques are known in the art, for example, about 1 to 3% by weight based on the weight of the monoester. By adding boron oxide, boron halide, boric acid or borate ester to the monoester as a slurry in mineral oil and heating with stirring at 135-165°C, then stripping and filtering the product with nitrogen. Implemented. The boronated product is generally approximately
It contains 0.1-2.0% by weight, preferably 0.2-0.8% by weight of boron. Metal salts of mono- and esters can be prepared by simply reacting the free succinic acid group of the mono- or diester with a suitable metal such as zinc acetate, nickel, copper or molybdenum in the presence of xylene and azeotropic acetic acid. Preference is given to the zinc, nickel, copper and molybdenum salts formed. Other suitable metals from which useful derivatives can be formed are calcium, barium and magnesium, which are commonly used in the production of antiwear additives and corrosion inhibitors. Ammonium salts are also suitable. Amine salts can generally be based on amino or polyamino compounds that are reactive towards free succinic acid moieties. Suitable amines are primary, secondary or tertiary hydrocarbyl and aliphatic hydrocarbyl mono- or polyamines having about 1 to 30 carbon atoms, such as methyl and ethylamine, aniline, diethanolamine, dipropylamine, ethylenediamine, morpholine, Includes phenylene and naphthalene diamines and the like. The products have been found to be useful as friction modifiers and corrosion inhibitors in automatic transmission fluids and similar functional fluids based on mineral oils, such as hydraulic fluids.
These range from about 0.05 to 2, based on the total weight of the composition.
Typical amounts are used, preferably 0.1 to 0.5% by weight. ATF compositions contain a number of conventional additives that perform their intended functions, which are typically mixed into the mineral oil base within the following ranges: Component concentration range (vol.%) VI improver 1-15 Corrosion inhibitor 0.01-1 Oxidation inhibitor 0.01-1 Dispersant 0.5-10 Pour point depressant 0.01-1 Demulsifier 0.001-0.1 Defoamer 0.001-0.1 Anti-wear additives 0.001-1 Seal lubricants 0.1-5 Friction modifiers 0.01-1 Mineral oil base Balance Typical base oils for automatic transmission fluids include:
Various light hydrocarbon mineral oils having a viscosity range of about 34 to 45 SUS (Saybold Universal Seconds) at 38 DEG C. may be mentioned, such as naphthenic base oils, paraffinic base oils, and hybrid base oils thereof. The present invention also relates to metal salt compounds derived from hydrocarbon-substituted succinic acids or anhydrides and useful as antioxidants, friction reducers, and corrosion inhibitors for automatic transmission fluids and similar functional fluids. More specifically, the present invention provides nickel mono- and diesters of thiobisalkanols and alkenylsuccinic acids or anhydrides that are particularly effective in providing oxidatively stable compositions in such automatic transmission fluids. or ATF compositions containing zinc salt derivatives. Zinc or nickel metal salts of mono- and diesters can be prepared by simply reacting the free acid groups of the mono- or diester with the metal, e.g. using zinc or nickel acetate in the presence of xylene and azeotropic acetic acid. This is the salt that is formed. It has been found that these should be used in amounts such that there is 0.5 mole of zinc or nickel per mole of monoester or diester to provide a suitable antioxidant. Compositions of the invention include automatic transmission fluids containing the metal salts described above and similar functional fluids, such as hydraulic fluids, based on mineral oils. These are used in typical amounts such as about 0.01 to 1% by weight, based on the total weight of the composition. The ATF compositions used in each of the examples below were formulated according to the ingredients and concentrations listed above;
This is called the base liquid. This base liquid contained conventional amine additives with or without zinc and nickel salts. Production 1 2-octadecenylsuccinic acid 6-hydroxy-
3,4-dithiahexyl ester (OSA-
Preparation of DBE) 0.2 mol (70 g) of 2-octadecenylsuccinic anhydride and 0.2 mol (30.8 g) of 2,2-dithiodiethanol are brought together and gradually heated to 140°C.
heated to. The mixture was stirred at this temperature until IR analysis showed the absence of anhydride carbonyl absorption. Elemental analysis showed 12.2% S. The theoretical value for the monoester is 12.7% S. Production 2 2-octadecenylsuccinic anhydride and 2,2'-
Preparation of diester with dithiobisethanol 150 g (0.43 mol) of 2-octadecenyl succinic anhydride was mixed with 140 g of 2-octadecenyl succinic anhydride while stirring under nitrogen atmosphere.
heated to ℃. Then 33 g (0.215 mol) of 2,
2'-dithio-bisethanol was added dropwise over 10 minutes. The mixture was stirred at this temperature until IR analysis showed the absence of anhydride carbonyl absorption. Elemental analysis showed 8.1% sulfur. The theoretical value for the bishemiesters is 7.5% S. Production 3 2-octadecenylsuccinic anhydride and 2,2'-
Preparation of monoester with thiobisethanol 0.4 mol (140 g) of 2-octadecenylsuccinic anhydride and 0.4 mol (48.8 g) of 2,2'-thiobisethanol were combined and slowly heated to 150°C. . The mixture was stirred at this temperature for about half an hour. Infrared analysis showed the absence of anhydride carbonyl absorption bands. Elemental analysis is 66.17% C,
It showed 10.33% H and 6.79% S, while the theoretical value of the monoester was 66.05% C, 10.23% H and
It is 6.78% S. Production 4 2-octadecenylsuccinic anhydride and 2,2'-
Preparation of diesters with thiobisethanol 636 g (1.81 mol) of 2-octadecenylsuccinic anhydride are heated to 150°C and 111 g (0.91
mol) of 2,2'-thiobisethanol was added dropwise over half an hour. The mixture was stirred at this temperature for an additional half hour or until IR analysis showed the absence of the anhydride carbonyl band. Production 5 2-octadecylthiosuccinic anhydride and 2,
Preparation with 2'-dithiodiethanol 57 g (0.15 mol) of 2-octadecylthiosuccinic anhydride (by addition of 1-octadecylmercaptan to maleic anhydride or by addition of mercaptosuccinic acid to 1-octadecene) (manufactured using
It was then combined with 11.6 g (0.075 mol) of 2,2'-dithiodiethanol. The THF solution was heated gradually and the THF was distilled off. The residue was heated to 140°C and kept at this temperature for half an hour. Infrared analysis showed the absence of anhydride carbonyl absorption bands. Production 6 2-octadecenylsuccinic anhydride and 2,2'-
Preparation of boronated derivatives of monoesters with dithiodiethanol 2-octadecenylsuccinic anhydride and 2,2-
0.1 mole (101.2 g) of a half-ester (monoester) with dithiodiethanol was combined with 0.1 mole (6.1 g) of boric acid in 100 ml of xylene.
The reaction mixture was heated to 140° C. for 4 hours until water evolution ceased. The xylene was distilled off and an oily residue was obtained. Infrared spectrum of the residue showed it to be the desired boronated ester. Production 7 Production of zinc, copper and nickel salts of the diester of octadecenylsuccinic anhydride and 2,2'-dithiobisethanol (a) 0.1 mol (85.4 g) of the diester of Production 2,
0.05 mol (10.98
g) with zinc acetate dihydrate. This mixture was heated to 140°C for 2 hours. The xylene was distilled off and the residue was further heated at 150°C under nitrogen for one more time.
heated for an hour. The residue solidified when cooled to room temperature. IR of the solid state showed carbonyl absorption bands characteristic of the desired zinc carboxylate salt. Elemental analysis showed 3.72% zinc. (b) Repeated the procedure in Production 7(a), but with the exception that 100 ml
0.05 mole (10.0 g) of cupric acetate in xylene was used. The residue likewise solidified upon cooling to room temperature and the IR spectral absorption band corresponded to the desired copper carboxylate.
Elemental analysis showed 3.59% copper. (c) Repeated the operation in (a) above, but with the exception of 100ml
0.05 mole (10.0 g) of nickel acetate in xylene was used. The residue likewise solidified upon cooling to room temperature, and the IR spectrum showed an absorption band corresponding to the desired nickel carboxylate. Elemental analysis showed 3.59% nickel. Example 1 (a) OSA of Preparation 1 containing conventional dispersants, antioxidants and seal swellers.
- Automatic transmission fluid containing 0.3% by weight of DBE was evaluated according to the Chevrolet Turbo Handramatic Oxidation Test (THM350) published by General Motors Corporation, Detroit, Michigan, USA. (July 1978, 2nd edition, appendix page 9, Standard G,
6137-M). The results and test criteria are shown below.
Test conditions were 300 hours at 325° (this test evaluates fluids in specially modified transmissions under specific conditions). THM350 Test Production 1 Liquid - Result Standard (Pass) TAN (Total Acid Number) ASTM D-664 Increase 5.09
Increased IR Carbonyl Absorption of 7 or less 0.442 Increase of 0.8 or less Transmission Components - Clean Clean Cooler Corrosion - Pass Pass (b) When the same formulation is evaluated for its wear reducing properties using the SAEN No. 2 friction machine, this It turned out to be effective. This test requires 100 hours of satisfactory operation without abnormal clutch plate wear or flaking of the composition facing plates.
After 24 hours of initial operation, dynamic torque is 115-175Nm
(Newton meter), and the static torque exceeds the dynamic torque by 14Nm.
Should not be exceeded more than. Clutch engagement time must remain between 0.45 and 0.75 seconds. (c) The same formulation was evaluated for corrosion inhibition using the Falex Pin corrosion test and the results are reported in the table below. The Farex Laboratory Friction Tester uses two "V" shaped blocks clamped against a rotating shaft.
This test is based on "Lubricant Testing" by E.G. Ellis, published by Scientific Publications Limited (1953, pp. 150-154).
It is described in. Load = occurrence of scoring 795Kg Pin wear = 10mg (227Kg load for 30 minutes) Block wear = 0.1mg (d) A 7.6 x 1.3 x 0.4cm copper and brass specimen calculated to 0.1mg was placed in 40cc of ATF from Example 1. A corrosion test was performed consisting of immersion in water and holding at 300°C for 65 hours. The specimens were then washed in hexane, rubbed to remove any loose deposits, and reweighed. The result is a copper loss of 10
mg and brass loss was 0 mg. Example 2 (comparative example) (a) “Improved Fuel
Report No. entitled “Economy Via Engine Oils”.
OSA-DBE of Preparation 1 was evaluated for friction reduction properties in a lubricating oil in the "Ball-On-Cylinder Test" reported in 780599. In this test, a steel ball (1.3 cm diameter) rubs against a 4.6 cm diameter steel cylinder at 0.26 rpm.
Both the ball and cylinder are SAE52100 medium alloy steel except the ball is hardened. The cylinder is moistened with 30 ml of test oil in a bath heated to 104°C. The test period is 60 minutes (16 rotations). The loads applied are 4Kg and 2Kg weights and a 2:1 arm ratio is used. ASTM High Reference Oil
A formulated lubricating oil composition was prepared according to the Specifications. It contained conventional amounts of anti-wear additives, overbased metal detergents and oil soluble dispersants and the base stock was a mineral paraffin oil having a viscosity of 31 cS at 37.8°C. this
The ASTM High Reference Oil blended oil is designated as Formulation A. Formulation B is the OSA-
Same mixture containing 1.0% by weight DBE.
The results of the comparative evaluation are shown below, which shows significant cylinder wear track data from the ball-on-cylinder test. This data shows that the coefficient of friction decreased without increasing cylinder wear scars.

[Table] (b) Next, the compounds of Preparations 2 and 4 were
Slow-Four Ball Test
Test)” (which is a measure of the frictional modification of additives in lubricating oils under more stringent conditions than the ball-on-cylinder test). The following results were obtained: Coefficient of Friction Reference Oil 0.23 Production 2 0.21 Production 4 0.24 Conventional Friction Modifier 0.09 All tests were carried out in
wt% additive concentrations were carried out. Example 3 (a) 2-octadecenylsuccinic anhydride (OSA)
and 2,2'-thiobisethanol (Preparation 4) was evaluated in the Allison _C3 Friction Test.
This test is a measure of the friction reduction that can be obtained with ATF. The following results were obtained.

Table: Thus, the product of Preparation 4 passed the friction modification test for ATF. (b) Oxidation inhibition of the product of Preparation 4 was evaluated in a turbo-hydramatic transmission cycling test. The acid value results are as follows. Acid value Production 4 1.7 Conventional antioxidant (C ₁₈ alkenyl succinic acid)
11.4 Maximum Acceptable Pass Value 6.0 Thus, the product of Preparation 4 passed the oxidation inhibition test used for evaluating ATF additives. Example 4 (Comparative) The product of Preparation 4 was then evaluated for friction modification in lubricating oil using the ball-on-cylinder test described above. The results are as follows.

Table: Thus, the product of Preparation 4 did not pass the test requirements for use as a friction reducer in lubricating oils, but did pass the friction modification requirements of the ATF test (if clutch pack is present). . Example 5 0.35% by weight of the zinc salt from production (7a) and the nickel salt from production (7c) were added to a fully formulated automatic machine fluid (base fluid). The fluids were evaluated in the LMOT (Laboratory Multistage Oxidation Test) and compared with the same fluids without zinc and nickel salts. In this LMOT test, a 50% solution containing 5 ml of copper naphthenate oxidation catalyst to which 2.0 g of iron filings was added was used.
ml of test solution is heated to 300㎓ and per minute
23 ml of air was bubbled through the sample. A sample is taken daily and the sample blotter spot is observed on the sludge. The number of days it takes for visible sludge to appear is the measure of antioxidant effectiveness. A score of 10-11 days is considered “passing.”
The results are shown below. LMOT result base solution 7 days Base solution + Zinc salt 15/16 days Base solution + Nickel salt 11 days

Claims (1)

[Claims] 1. Mineral oil of lubricating viscosity and formula A mono- or diester friction modifier represented by 0.05 wherein R ₁ is selected from the group consisting of hydrogen and An automatic transmission fluid composition comprising ~2% by weight. 2. The composition according to claim 1, wherein the ester is a monoester. 3. The composition according to claim 1, wherein the ester is a diester. 4. The composition according to claim 1, wherein x is 1. 5. The composition according to claim 1, wherein the ester is boronated. 6 Mineral oil of lubricating viscosity, and formula Zinc, copper or nickel of the compound represented by: wherein R ₁ is selected from the group consisting of hydrogen and An automatic transmission fluid composition containing 0.05 to 2% by weight of salt.