JPH08283233A - Lubricating oil composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a sulfur-containing compound useful as a base fluid of a lubricating oil and obtain a lubricating oil composition therefrom.

SOLUTION: This compound is represented by the formula {A is H or a 1-30C alkyl; B is a 1-30C alkyl, CO₂, W, Y-CO₂-Z or the like; W and Z are each an alkyl; Y is an alkylene; R' and R'' are each independently H, an alkyl, CH₂ or the like; (p) is 0-40; X is CO₂, a 1-30C alkyl or the like; (n) is 1-12, except for a compound represented by S(CH₂CH₂CO₂R)₂ or the like}, e.g. hexyl 9(10)-(hexyloxycarbonylmethylthio)octadecanoate. The compound of the formula is obtained by reacting an olefinic unsaturated compound with a sulfur- containing compound (e.g. hydrogen sulfide), and as necessary, esterifying the reaction product. The compound has at least 440 molecular weight. The lubricating composition contains the compound of the formula, preferably in an amount of 5-25 wt.% based on the total base fluid and contains a base derived from a mineral oil or synthetic oil in the remainder.

COPYRIGHT: (C)1996,JPO

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to sulfur-containing compounds and their use as base fluids in lubricating oil compositions.

[0002]

BACKGROUND OF THE INVENTION The need for oxidative stability of engine lubricants has led to increased oil spill intervals, localized increases in operating temperature and increased engine cleanliness in some applications. It continues to increase, coupled with the need to keep vehicle emissions performance low. In addition, the demand for low-viscosity engine oil is increasing due to the demand for improving the economy of automobile fuels.
Further, there is a demand for a base fluid having both low viscosity and low volatility. Also, if the viscosity index of the base fluid can be increased, the desired viscosity and volatility can be achieved.

Oxidation resistance can be improved by the use of antioxidants in the lubricant composition, the use of inherently more stable lubricant base fluids, or a combination of these methods. The compounds of the present invention have other physical fluid properties (viscosity, viscosity index, pour point and volatility) required for lubricating oil blending.
While maintaining the above, a lubricating oil composition containing these compounds as a base fluid is provided with excellent oxidation resistance by incorporating an antioxidant function into the compound molecule. Some currently used antioxidants have the practical drawback of being solid or of relatively high volatility for lubricating oil applications. Such drawbacks are
Solved by the compound of the present invention.

Magne et al., J. Am. Oil Chem. Soc. 19
75, 52, pages 494-497 describe a number of fatty acid esters as lubricants and lubricant additives, which are particularly responsible for antiwear and extreme pressure performance. Sample 3 of that document
6 is 2- (2-ethoxyethoxy) -ethyl-9 (1
0)-(carbobutoxymethylthio) stearate. However, as described below, the compound has been found to be unacceptable in terms of compatibility with elastomer seals.

GB-A-863339 discloses extreme pressure agents containing small amounts of oil-soluble aliphatic compounds, which compounds contain as substituents at least one oxygen-containing group Y and 1 to 4 groups. formula _{-S- (CH 2) n -X (} Y is an alcohol, ether, carboxylic acid or ester radical, n
Is 1 to 4, X is -OR or -COOR (R is
Is a hydrogen atom or a C ₁ -C ₄ alkyl group. ). ), Wherein at least one of the --S-(CH ₂ ) _n --X groups is separated from the group Y by a chain of at least 7 carbon atoms. Of the GB-A-863339 examples, only Example II discloses the ester in composition E and is tested only for its extreme pressure properties (Table I).
I).

Commercially available antioxidants containing one sulfide bond and two carboxylic acid ester groups are of formula S
Examples thereof include thiodipropionate of (CH ₂ CH ₂ CO ₂ R) _2. Examples thereof include “Irganox” manufactured by Ciba-Gaigy.
There are PS800 "(R is n-dodecyl) and" DTDTDP "from Akcros (R is n-tridecyl). However, the former of the above compounds is a solid and is therefore totally unsuitable as a base fluid for lubricants. The latter of the above compounds is a liquid, but is commercially available as a polymer stabilizer, ie for applications which have nothing to do with what is intended by the present invention.

[0007]

According to the present invention, the following formula:

[0008]

[Chemical 4]

[Wherein A is a hydrogen atom or an alkyl group; B is an alkyl group, or a group of the formula CO ₂ -W (W is an alkyl group), or a formula of Y-CO ₂ -Z (Y Is an alkylene group and Z is an alkyl group),
Or a group of the formula CH ₂ CH (CO ₂ D) CH ₂ CO ₂ E (D and E are each independently an alkyl group); R ′ and R ″ are each independently a hydrogen atom, alkyl Group or CH ₂ CO ₂ F (F is an alkyl group.)
Or p is 0 to 40; X is a group of CO ₂ G (G is a C _1-30 alkyl group) or (CH ₂ ) _n
CO ₂ J (J is a C _1-10 alkyl group, n is 1 to 12)
Is. A compound of formula S (CH ₂ C) having a molecular weight of at least 440.
H ₂ CO ₂ R) ₂ or S (CH ₂ CO ₂ R) ₂ (R is an alkyl group) compound of formula CH ₃ (CH ₂ ) ₈ —
_{CH (SCH 2 CO 2 L)} - (CH 2) 7 -CO 2 K
(Wherein K and L are each an octyl group, or K is a butyl group and L is an ethyl group), and a compound of the formula MO ₂ C-
_{CH 2 -CH (SN) -CO 2} M (M is a decyl group, N represents a dodecyl group) provides a compound characterized by excluding.

[0010]

Suitable electron withdrawing groups include esters, ketos, nitros, nitrites, halogens, aryl ethers, alkoxy thiyl, (thyl), hydroxy, alkenes, alkynes, acid anhydrides and aryl (acyl-acyl- Or alkyl-substituted aryl). Preferably, the electron withdrawing group is a carbonyl group.
Most preferably, the electron withdrawing group is an ester carbonyl group.

In the compounds of formula I above, preferably
A is hydrogen atom or a C _1-30 alkyl group, more preferably a hydrogen atom or a C _1-16 alkyl group; B is C _1-30 alkyl groups, more preferably C _1-16 alkyl group or C,
O ₂ -W (W is a C _1-30 alkyl group, more preferably C
_{It is a 3-12} alkyl group. ) Group, or Y—CO ₂ —Z
(Y is a C _1-30 alkylene group, more preferably a C _1-15 alkylene group, Z is a C _1-30 alkyl group, more preferably a C _4-12 alkyl group) or CH ₂ CH
(CO ₂ D) CH ₂ CO ₂ E (D and E are each independently a C _3-15 alkyl group, more preferably a C _7-9 alkyl group); R ′ and R ″ are Each is independently a hydrogen atom, or a C _1-10 alkyl group, more preferably a butyl group, or CH ₂ CO ₂ F (F is a C _3-15 alkyl group, more preferably a C _7-9 alkyl group. ); P is 1 or 2; X is CO ₂ G (G is C
_{It is a 1-12} alkyl group. ) Group or (CH ₂ ) _n CO
₂ J (J is a hexyl group and n is 7 to 8).

According to the invention, there is also provided a process for the preparation of the compounds of the invention, which process comprises reacting an olefinically unsaturated compound with a sulfur-containing compound and, if necessary, esterifying the compound thus obtained. Including that.

In the method of the present invention, the sulfur-containing compound is preferably hydrogen sulfide, thiol, thiophenol or thiol acid.

According to the present invention, the base fluid further has the following formula:

[0015]

Embedded image

[Wherein A is a hydrogen atom or an alkyl group; B is an alkyl group, or a group of the formula CO ₂ -W (W is an alkyl group), or a formula Y-CO ₂ -Z (Y Is an alkylene group and Z is an alkyl group),
Or a group of the formula CH ₂ CH (CO ₂ D) CH ₂ CO ₂ E (D and E are each independently an alkyl group); R ′ and R ″ are each independently a hydrogen atom, alkyl Group or CH ₂ CO ₂ F (F is an alkyl group.)
Or p is 0 to 40; X is a group of CO ₂ G (G is a C _1-30 alkyl group) or (CH ₂ ) _n
CO ₂ J (J is C _1-10 alkyl group, n 12
Is. ), Provided that the formula S (CH ₂ CH ₂ CO
₂ R) ₂ or S (CH ₂ CO ₂ R) ₂ (R is an alkyl group), a compound of formula CH ₃ (CH ₂ ) ₈ —CH
_{(SCH 2 CO 2 L) -} (CH 2) a compound of ₇ -CO ₂ K (K and L are each an octyl group), and wherein M
_{O 2 C-CH 2 -CH (} SN) -CO 2 M (M is a decyl group, N represents a dodecyl group) The compound except, to include compounds having a molecular weight of at least 440 Provided is a lubricating oil composition containing the characteristic lubricating oil composition as a base fluid.

In the lubricating oil composition of the present invention, the compound is preferably present in an amount of 2 to 100% by weight, more preferably 5 to 25% by weight, based on the total base fluid.

Further, in the lubricating oil composition of the present invention,
The balance of the total base fluid is base oil, preferably derived from mineral or synthetic oils.

According to the present invention, as the base fluid in the lubricating oil composition, the following formula:

[0020]

[Chemical 6]

[Wherein A is a hydrogen atom or an alkyl group; B is an alkyl group, or a group of the formula CO ₂ -W (W is an alkyl group), or a formula of Y-CO ₂ -Z (Y Is an alkylene group and Z is an alkyl group),
Or a group of the formula CH ₂ CH (CO ₂ D) CH ₂ CO ₂ E (D and E are each independently an alkyl group); R ′ and R ″ are each independently a hydrogen atom, alkyl Group or CH ₂ CO ₂ F (F is an alkyl group.)
Or p is 0 to 40; X is a group of CO ₂ G (G is a C _1-30 alkyl group) or (CH ₂ ) _n
CO ₂ J (J is C _1-10 alkyl group, n 12
Is. The use of a compound according to [1] is also provided.

Suitable olefinically unsaturated starting materials used for the production of sulfur-containing compounds include (a) α-olefins; internal olefins obtained by partial isomerization of α-olefins (unsaturation is in principle β
-C = C bond, but is not limited thereto. ); Α-
Internal olefins obtained by complete isomerization of olefins (C = C bonds are randomly distributed over all possible positions of the hydrocarbon chain); internal C-C bonds are at specific positions of the hydrocarbon chain, for example in the middle Olefins; olefins obtained by the oligomerization of propene or butene; olefins obtained by the dimerization or higher oligomerization of α-olefins higher than C ₄ or internal olefins (eg C ₈ , C ₁₀ or C ₁₂ olefins); Olefin obtained by cracking a substance having a high molecular weight, such as wax, (the carbon number of the olefin is C _8-1000 , preferably C _10-100 , most preferably C _16-40 . The olefin is a straight chain or a branched chain. Or cyclic, and may be further substituted with another group such as an aryl group.); ) Vegetable oils, such as soybean oil, sunflower oil, corn oil, high erucic acid rapeseed oil, low erucic acid rapeseed oil, olive oil, tall oil, of triglycerides (at least 60% by weight of the constituent fatty acids have at least one C = C bond). , Groundnut oil, castor oil, vernonia
ia) oil and the like; derivatives of the vegetable oil, such as oleic acid, linoleic acid, linolenic acid, erucic acid, ricinoleic acid, docosenoic acid, which are the constituent fatty acids of the vegetable oil; or esters of the fatty acid, such as methyl oleate and linole methyl acid, glycerol trioleate; (c) at least one C = organic acid having C bond, preferably an alkyl of alkenoic acids R-C = C-Y- CO 2 H (R is 1 to 100 carbon atoms , Aryl or acyl, and Y is an alkylene group having 1 to 30 carbon atoms.).

Alternatively, the compounds of this invention can be synthesized by the reaction of an olefinically unsaturated acid anhydride, such as maleic anhydride.

The compounds of the present invention may be prepared by known methods, eg, one of the above olefinically unsaturated materials of a suitable sulfur-containing compound (eg hydrogen sulfide, thiol, thiophenol or thiolic acid (eg mercaptoacetic acid)).
It can be synthesized by electrophilic, nucleophilic or free radical addition with olefins or olefinically unsaturated acids (such as oleic acid). Suitable free radical initiators include organic peroxides such as lauroyl peroxide. The obtained intermediate may contain one or more carboxylic acid groups, and the carboxylic acid groups may be converted into an acid such as sulfuric acid, 4-toluenesulfonic acid or methanesulfonic acid, or a metal alkoxide such as titanium isopropoxide. Alternatively, it can be esterified by reaction with an alcohol or a mixture of alcohols in the presence of a catalyst due to the acid sites of the ion exchange resin, or in the absence of a catalyst. If the intermediate already contains ester (eg methyl ester) groups, these ester groups may be transesterified by acid-catalyzed reaction with another alcohol or alcohol mixture using the acid catalysts listed above. it can.
Suitable alcohols include straight chain primary alcohols, such as straight chain primary C _3-20 alcohols, preferably straight chain primary C
_5-10 alcohols; or branched chain alcohols with the same carbon number range, eg having one or more methyl or ethyl substituents.

Suitable additives for use in the engine oils with the compounds of the present invention may include one or more extreme pressure / antiwear agents, for example zinc salts such as dialkyl phosphorus dithionate or diaryl zinc. (0 in lubricant
˜0.15% by weight phosphorus); one or more overbased metal-containing detergents (such as calcium or magnesium salts of alkylsalicylic acid or alkylarylsulphonates, 0-2% by weight in the lubricant). Present in total detersive metal concentration); one or more ashless dispersants such as reaction products of polyisobutenyl succinic anhydride with amines or esters (present in lubricants at 0-10 wt% total dispersed actives concentration). Optionally one or more major antioxidants, such as hindered phenols or amines (0 to 0 in the lubricant)
Present at a concentration of 5% by weight). Other auxiliary additives, such as rust inhibitors or friction modifiers, may optionally be present. Viscosity index improving polymers can also be present, if desired, at polymer concentrations of 0-10% by weight. Pour point depressants can also be present, if desired, in concentrations of 0-5% by weight.

The remaining base oil in the lubricant may be a base oil derived from mineral oils or synthetic oils. Examples of the base oil derived from mineral oil include mineral oil obtained by solvent refining or hydrotreating. The base oil derived from synthetic oil is
It is typically a mixture of _C10-50 hydrocarbon polymers, such as liquid polymers of alpha-olefins. It may also be a normal ester, for example a polyol ester.
The base oil may also be a mixture of these oils.
A preferred base oil is Royal Dutch under the name "HVI".
/ Base oil derived from mineral oil marketed by Shell Group of Companies, most preferably "XHV
Royal Dutch / Shell Group of "I" (trademark)
It is a synthetic hydrocarbon base oil marketed by Companies.

[0027]

EXAMPLES The preparation of the compounds of the present invention is described in the following Examples 1-15.
This will be described below.

Example 1 9 (10)-(hexyloxycarbonylmethylthio)
Synthesis of hexyl octadecanoate 70% oleic acid (12 kg, 42.49 mol), freshly distilled mercaptoacetic acid (5.9 kg, 64.05)
Mol) and lauroyl peroxide (0.1 kg) were stirred under a nitrogen atmosphere and heated to 60 ° C. Furthermore, 0.1 kg of peroxide is added every 3 hours for a total reaction time of 45 hours.
Was added. The mixture was heated at 90 ° C. for a further 2 hours, then cooled to room temperature and diluted with toluene (17 l). The toluene solution was washed with water (5 x 8 liters), dehydrated by azeotropic distillation and n-hexanol (14 liters) and methanesulfonic acid (0.32 kg) were added. Warm the reaction,
Reflux until the steam temperature rises to 110 ° C, then
Distillation was continued for another 4 hours. After cooling to room temperature, the solution was washed with water (4 l) and aqueous sodium bicarbonate solution (4 l), dried (Na ₂ SO ₄ ) and filtered. The filtrate was continuously stirred overnight with pre-activated "Amberlite A-26" ion exchange resin (2 x 1 kg, 1 x 2 kg), filtered and the solvent evaporated. 140 ° C / 1m
22.5 kg when the wiped film is evaporated at a bar of about 750 ml / hour.
When the residue was subjected to redistillation at 185 ° C./1 mbar and a passage rate of about 750 ml / hour, 9 (10)-
Hexyl (hexyloxycarbonylmethylthio) octadecanoate (20.2 kg) was obtained as an orange / brown oil.

Activation of ion exchange resin: "Amberlite A-26" ion exchange resin (2 kg) was added to concentrated hydrochloric acid (30 kg).
0 ml) in methanol (2.7 l) and the mixture was stirred for 15 minutes. The resin was loaded onto the column and washed with deionized water until the wash was neutral (required about 20 l). After eluting with 2 M aqueous sodium hydroxide solution (3 l), the resin was washed again with deionized water until the wash was neutral (required about 12 l). Finally, the column was analyzed by Karl-Fisher analysis with a water content of <1% in the eluent
Washed with methanol (requires about 10 l).

Example 2 9 (10)-(dodecyloxycarbonylmethylthio)
Synthesis of dodecyl octadecanoate 90% oleic acid (400 g, 1.42 mol) and freshly distilled mercaptoacetic acid (196.2 g, 2.1
3 mol) was stirred under a nitrogen atmosphere and heated to 60 ° C.
Lauroyl peroxide (3g) was added and heating continued. Furthermore, lauroyl peroxide was added to the total reaction time of 30 hours for 3 hours.
3 g was added every hour. The mixture was cooled, diluted with diethyl ether (500 ml) and water (2 × 75 m).
It was washed with 1) and dehydrated (Na ₂ SO ₄ ). The solvent was evaporated, yielding intermediate C (606g).

Intermediate C (300 g, 0.8 mol), n-
Dodecanol (447.2 g, 2.4 mol) and methanesulfonic acid (7.5 g) were dissolved in toluene, heated and refluxed with a 30-stage splitting column. Steam temperature is 110
After reaching ° C, distillation was continued for about 2 hours. Cool the solution,
It was washed with water (2 × 250 ml) and saturated aqueous sodium bicarbonate solution (250 ml) and dried (MgSO ₄ ).
The filtrate was continuously stirred overnight with activated “Amberlite A-26” ion exchange resin (2 × 30 g, 2 × 50 g), filtered and the solvent was evaporated. Wipe film distillation of volatile impurities (185 ° C / 0.8 mbar
When removed by r), dodecyl 9 (10)-(dodecyloxycarbonylmethylthio) octadecanoate (44
4 g) was obtained as an oil.

Example 3 11- (Hexyloxycarbonylmethylthio) unde
Synthesis of Hexyl Cyanate 10-Undecanoic acid (180 g, 0.98 mol) and freshly distilled mercaptoacetic acid (135 g, 1.47 mol) were stirred together and the temperature was raised to 100 ° C. The mixture was heated at 110 ° C. for 2 hours and cooled to 60 ° C. Carbon tetrachloride (300 ml) was added and the solution was crystallized. The resulting white solid was filtered, washed with carbon tetrachloride and hexane, and dried under vacuum at 40 ° C. to give 11- (carboxymethylthio) undecanoic acid (279.9 g) (Compound E).

A solution of compound E (276 g, 1 mol), n-hexanol (276 g, 2.7 mol) and methanesulfonic acid (5.5 g) in toluene (2 l) was warmed to 3
The mixture was refluxed by a 0-stage splitting column. After the temperature of the steam reached 110 ° C., the distillation was continued for about 3 hours. The solution was cooled and water (2
× 75 ml) and washed with saturated aqueous sodium bicarbonate, dried (MgSO _4). The filtrate was continuously stirred overnight with “Amberlite A-26” resin (2 × 100 g, 2 × 25 g), filtered and subjected to wipe film distillation (140 ° C./0.1 mbar) 298.
1 l of crude product was obtained as a yellow oil. Redistillation of 223 g of the material at 150 ° C./0.5 mbar yielded 133.7 g of hexyl 11- (hexyloxycarbonylmethylthio) undecanoate.

Example 4 13 (14)-(hexyloxycarbonylmethylthio)
E) Synthesis of hexyl docosanoate Docosanoic acid (50 g, 0.15 mol) and freshly distilled mercaptoacetic acid (20.7 g, 0.23 mol) were warmed to 60 ° C under a nitrogen atmosphere. Lauroyl peroxide (0.
4 g) was added and stirring was continued. Furthermore, 0.4 g of lauroyl peroxide was added every 3 hours until the total reaction time of 55 hours.
Was added. The mixture was cooled and diethyl ether (1
It was diluted with 50 ml), washed with water (2 × 25 ml) and dried (MgSO ₄ ). Upon evaporation of the solvent, intermediate F
(72.0 g) was obtained as an oil. The intermediate was synthesized twice.

Intermediate F (150 g, 0.35 mol), n
-Hexanol (96.1 g, 0.94 mol) and methanesulphonic acid (2.5 g) were dissolved in toluene (1 l), warmed and refluxed in a 30 stage split column. After the temperature of the steam reached 110 ° C., the distillation was continued for about 2 hours. The solution was cooled, washed with water (2 × 100 ml) and saturated aqueous sodium bicarbonate (100 ml), dried (MgSO ₄₎
did. The filtrate was activated with "Amberlite A-26".
Stir overnight with resin (2 x 100g) overnight,
Filter and evaporate the solvent. Volatile impurities were removed by wipe film distillation (180 ° C./0.1 mbar) to give hexyl 13 (14)-(hexyloxycarbonylmethylthio) docosanoate (134.7 g) as an oil.

Example 5 9 (10)-(Butoxycarbonylmethylthio) octa
Synthesis of butyl dodecanoate 70% oleic acid (2.4 kg, 8.5 mol), freshly distilled mercaptoacetic acid (1.17 kg, 12.75)
Mol) and lauroyl peroxide (24 g) were stirred under a nitrogen atmosphere and heated to 60 ° C. Add 4 more peroxides
24 g was added every 3 hours up to a total reaction time of 5 hours. The mixture was heated at 90 ° C. for a further 2 hours then cooled to room temperature and diluted with toluene (11 l). The toluene solution was washed with water twice and dehydrated (MgSO ₄ ) to give intermediate G
A solution of was obtained, which was not isolated. The solution was divided into two solutions in equal volumes.

One solution of the intermediate G, n-butanol (1.66 kg, 22.4 mol) and methanesulfonic acid (34 g) were put in toluene (6 l), which was warmed and refluxed by a 30-stage splitting column. . After the temperature of the steam reached 110 ° C., the distillation was continued for about 2 hours. The solution was cooled to room temperature, washed with water (500 ml) and saturated aqueous sodium bicarbonate solution (200 ml), dried (MgSO ₄ ) and filtered. The filtrate was treated with activated "Amberlite A-2.
Continuously stirred with 6 "resin (3 x 300 g) overnight, filtered and the solvent evaporated. 1.71k when subjected to wipe film distillation (160 ° C / 1.4 mbar)
g residue was obtained. Redistillation at 180 ° C./1.1 mbar gave butyl 9 (10)-(butoxycarbonylmethylthio) octadecanoate (1.54 kg) as an orange-brown oil.

Example 6 9 (10)-(alkoxycarbonylmethylthio) octyl
Alkyl tadecanoate (alkyl = heptyl, octyl,
Nonyl mixture; alkoxy = heptyloxy, octyl
Oxy, other solution of intermediate G of Example 5 of the mixing nonyloxy), C ₇ -C ₉ straight chain primary alcohols (Shell made "LINEVOL 79" (trade mark)
A mixture of (1.62 kg, about 12.7 mol) and methanesulfonic acid (34 g) was put in toluene (5 l), which was warmed and refluxed by a 30-stage splitting column. After the temperature of the steam reached 110 ° C., the distillation was continued for about 2 hours. The solution was cooled to room temperature, washed with water (500 ml) and dehydrated (MgS
O ₄ ) and filtered. The filtrate was continuously stirred overnight with activated "Amberlite A-26" resin (3 x 300 g), filtered and the solvent was evaporated. When subjected to wipe film distillation (160 ° C / 1.3 mbar),
A 2.45 kg residue was obtained. 180 ° C / 1.0mb
Redistillation with ar yields an alkyl 9 (10)-(alkoxycarbonylmethylthio) octadecanoate (2.22k
g) was obtained as an orange-brown oil (alkyl = heptyl, octyl, nonyl; alkoxy = heptyloxy, octyloxy, nonyloxy).

Example 7 Mixture (1-9)-(alkoxycarbonylmethylthio)
Octadecane (alkoxy = heptyloxy, octyl
Oxy, nonyloxy) Fully isomerized mixture of C ₁₈ olefins (161.6
g, 0.64 mol), mercaptoacetic acid (88.4 g,
0.96 mol) and lauroyl peroxide (1 g) 62
After heating at 0 ° C. for 6 hours, an additional 0.5 g of lauroyl peroxide was added over a further 12 hours. The mixture was cooled, diluted with pentane (100 ml) and washed with water,
It was dehydrated (Na ₂ SO ₄ ). After evaporation of the solvent, the intermediate was mixed with a 2: 1 molar excess of mixed linear primary C ₇ , C ₈ and C
_It was mixed with ₉ alcohol ("Linevol 79" (TM) from Shell) and 0.15 ml titanium isopropoxide.
After heating the mixture to 200 ° C. for 4 hours, excess alcohol was removed by vacuum distillation. The product was dissolved in hexane, passed through silica gel (20-45 μm) to remove catalyst residue, and hexane was evaporated in vacuo to give 225 g of product.

Example 8 Mixed 9- (alkoxycarbonylmethylthio) octade
Can (alkoxy = heptyloxy, octyloxy,
Synthesis of nonyloxy) 9-octadecene (162 g, 0.64 mol), mercaptoacetic acid (82.9 g, 0.90 mol) and lauroyl peroxide (1 g) were heated to 80 ° C. and lauroyl peroxide was added for 26 hours. 3 hours and 8 for total reaction time
1 g each was added over the time. The mixture was cooled, added the same amount of toluene and washed 6 times with water. Intermediate acid, p
-Toluenesulfonic acid (1% by weight with respect to alcohol)
As a catalyst, an excess of 20% by mole of mixed linear primary C ₇ , C
Esterified with ₈ and C ₉ alcohols ("Linevol 79" (TM) from Shell). After reacting for 4 hours, the mixture is washed with water until the pH of the aqueous phase is neutral and the solvent and unreacted alcohol and olefin are removed by vacuum distillation to give mixed 9- (alkoxycarbonylmethylthio) octadecane. Was obtained.

Example 9 Mixed 11- (alkoxycarbonylmethylthio) docosa
(Alkoxy = heptyloxy, octyloxy, no
Synthesis of nyloxy) 11-dococene (308.6 g, 1.0 mol) was reacted with mercaptoacetic acid (138.2 g, 1.0 mol) and the intermediate was treated under the conditions described in Example 8. Mixed straight chain primary C ₇ , C ₈ and C ₉ alcohols (Shell's "Linevo
l 79 "(trademark)). Wipe film evaporation of residual olefin and alcohol (180 ° C / 0.2m
Removal by bar) gave mixed 11- (alkoxycarbonylmethylthio) docosane.

Example 10 Mixed (1-9)-(alkoxycarbonylmethylthio)
Heptadecane, (1-9)-(alkoxycarbonylmeth)
Tylthio) octadecane and (1-10)-(arco
Xycarbonylmethylthio) nonadecane (alkoxy =
Heptyloxy, octyloxy, nonyloxy)
Formation: For 2-position substituent C _17, C ₁₈ and C ₁₉ mixture of internal olefins (500
g, 2.0 mol) was reacted with mercaptoacetic acid (276 g, 3.0 mol) at 80 ° C. for 24 hours. During this time, lauroyl peroxide (3.0 g) was added stepwise as an initiator. The product was diluted with toluene and washed with water to give a 20 mol% excess of alcohol and p-toluenesulfonic acid (PTSA) (PTSA: alcohol molar ratio = 1: 1).
00) esterified with a first C ₇ -C ₉ alcohol mixtures linear using as catalyst (Shell made "LINEVOL 79" (trade mark)), and washed, distilled in the same manner as in Example 13.

Example 11 3-alkoxycarbonyl-4 (5)-(alkoxycarboxyl)
Rubonylmethylthio) nonanoic acid mixed alkyl (alkyl
= Heptyl, octyl and nonyl; alkoxy = hep
Tyloxy, octyloxy and nonyloxy)
Formed The product was obtained analogously to the method of Example 12,
Hexenyl succinate was used instead of maleic anhydride. The intermediate diester was not separated. After free radical addition of mercaptoacetic acid, the added acid groups were further esterified with "Linevol 79" (TM) from Shell.

Example 12 2- (Alkoxycarbonylmethylthio) succinic acid mixture
Dialkyl (alkyl = heptyl, octyl and noni
Alkoxy = heptyloxy, octyloxy and
And nonyloxy) maleic anhydride (0.5 mol) is mixed with 1.6 mol of mixed linear primary C ₇ -C until the theoretical amount of water is removed azeotropically.
₉ Reacted with alcohol ("Linevol 79" (TM) from Shell). Excess alcohol was distilled off. The diester obtained was reacted with a 50 mol% excess of mercaptoacetic acid. The majority of the reaction was complete within 4 hours, while the reaction lasted a total of 24 hours, during which time a total of 3.0 g lauroyl peroxide was added in stages. The mixture was purified by passing through a silica gel column, eluting with hexane, then dichloromethane and finally dimethyl ketone.
Dimethyl ketone was removed from the eluent by evaporation and the resulting residue was esterified with "Linevol 79" ™ from Shell to give the title material.

Example 13 Mixture 11 (12)-(2-alkoxycarbonylethyl)
Thio) docosane (alkoxy = heptyloxy, octy
Synthesis of 11-dococene (388 g, 1.26 mol) at 80 ° C.
At room temperature for 26 hours with a 50 mol% excess of 3-mercaptopropionic acid. During this time, lauroyl peroxide was added stepwise as a free radical initiator. 3.0g in total
Of lauroyl peroxide was added. The obtained intermediate was diluted with the same amount of toluene and washed with water 6 times. Intermediate, p
-Toluenesulfonic acid (1% by weight with respect to alcohol)
With 20 mol% excess of mixed linear first C ₇ -C as a catalyst
₉ Esterified with alcohol ("Linevol 79" (TM) from Shell). The reaction was complete after 4 hours, the product was washed with a slight excess of aqueous sodium hydroxide solution and then repeatedly with water until the pH of the aqueous phase was neutral. Toluene, excess alcohol and unreacted olefin were removed by vacuum distillation.

Example 14 9 (10)-(2-hexyloxycarbonylethylthio)
E) Synthesis of hexyl octadecanoate Oleic acid (28.3 g, 0.10 mol) and 3-mercaptopropionic acid (16.0 g, 0.15 mol) were reacted at 60 ° C. under nitrogen for 32 hours. 6
g of lauroyl peroxide were added in stages. The mixture was heated at 60 ° C for a further 16 hours, then at
Heat for hours, cool, and remove diethyl ether (100 m
diluted with l), washed with water and dried (MgSO _4), and removal of the solvent, 9 (10) - (carboxyethylthio) octadecanoic acid was obtained as an orange oil. Hexanol (31.4 g, 0.31 mol), methanesulfonic acid (0.84 g, 9 mmol) and toluene (1
50 ml) was added and the mixture was refluxed to remove water.
The mixture was cooled, washed with water, treated with calcium hydroxide (8.5 g) and water (1 ml), then MgS.
It was dehydrated with O ₄ . The solvent was removed on a rotary evaporator to give an oil (91.5g). It was re-treated with calcium hydroxide and water, filtered, treated with anhydrous sodium carbonate and water and filtered. The product was vacuum distilled on a rotary evaporator followed by a wipe film evaporator to yield 36.8 g of 9 (1
0)-(2-hexyloxycarbonylethylthio) hexyl octadecanoate was obtained.

Example 15 Hexyl 9 (10)-(octylthio) octadecanoate
Was synthesis in the same manner as in Synthesis Example 14, oleic acid (2
8.4 g, 0.10 mol), octane thiol (23.
5 g, 0.16 mol) and lauroyl peroxide (3.6
g) was used. After esterification, treatment with calcium hydroxide (twice) and sodium carbonate, followed by wipe film evaporation gave 30.0 g of 9 (10)-.
Hexyl (octylthio) octadecanoate was obtained.

Table 1 shows the physical properties of the compounds of the present invention.

[0049]

[Table 1]

(A) Abnormal behavior * Noack method (Test method CEC-L-40-T-8
7) measures loss due to evaporation from oil held at 250 ° C.

** TGA is test method IP 393/91. Weight loss up to 262 ° C from 40 ° C to 550
Measured from the recording of the mass loss as a function of temperature in a suitable thermogravimetric analyzer experiment at a constant heating rate of 10.degree. This measurement has been found to give an indication of the results expected by the Noack method (based on the use of limited correlation).

Since these compounds have a high viscosity index and a low pour point, the product viscosity is in a suitable range as a lubricant, particularly as an engine lubricant.

The stability of the oil against oxidation was evaluated by a differential scanning calorimeter (DSC). DSC measures the differential heat flow (sample vs control) when a sample oil in a small pan and a control (empty pan) are heated in a closed cell under an atmosphere of oxygen or air. Suitable devices are commercially available from various vendors. Since oil oxidation is exothermic, DSC can be used to monitor the oil oxidation rate. Typically, 2 mg of sample oil is used in an open aluminum dish. Two types of experiments were conducted.

(A) In a temperature programmed (dynamic) experiment, the test temperature was 40 ° C to 400 ° C at 20 ° C / min.
A linear gradient of ° C was applied. The cell was filled with an oxygen atmosphere of 2 bar and the gas flow rate was 60 ml standard / min. The rapid onset of oxidation is evident from the rapid increase in exotherm. The extrapolated generated temperature is defined by the intercept of the tangent line at the steepest part of the increasing heat generation and the extrapolated baseline from the lower temperature in the plot of heat generation power vs. temperature.

(B) In isothermal experiments, the temperature is kept constant at a selected temperature, for example 220 ° C. 30 in the cell
Oxygen atmosphere of bar and flow rate of gas 60ml standard /
Minutes If the oil contains a first antioxidant, the induction phase (the rate of oxidation is regulated by the antioxidant, so that most of the heat is generated before the rapid oxidation shown by the rapidly increasing exotherm) occurs. There is a period (not allowed). The induction period is defined in the plot of exothermic power versus time by the intercept of the tangent at the most abrupt part of the increasing exotherm and the baseline extrapolated from earlier times.

Table 2 shows the extrapolated temperatures of the compound of the present invention, the polyol ester of Comparative Example (Comparative Example A) and the synthetic hydrocarbon of Comparative Example (Comparative Example B).

[0057]

[Table 2]

It can be seen that the compounds of the present invention have a much higher extrapolated temperature than polyol ester or synthetic hydrocarbon fluids.

Table 3 lists the engine lubricants containing the compounds of the present invention, as well as other hydrocarbon base oils and zinc dithiophosphates, overbased metal detergents, ashless dispersants and auxiliary primary antioxidants. 220 of a lubricant composition (compositions B-H) containing an additive package (package A) suitable for the application.
Shows the induction period measured by isothermal DSC at ° C. For comparison, Table 3 shows that the polyol esters currently used in lubricating oils (Comparative Example A) and Comparative Example C (2,2′-thiodiethanoic acid mixed dialkyl S (C)
H ₂ CO ₂ R) ₂ ; R = mixture of branched C _14-18 alkyls) is also included.

[0060]

[Table 3]

[0061]

[Table 4]

Polyol esters are known to increase oxidative stability compared to hydrocarbon-based fluids. However, when used in admixture with a hydrocarbon-based fluid, little or no oxidative stability of the mixture was observed at low ester concentrations, for example below 50% by weight of the mixture. Composition J was prepared by mixing Comparative Example A at a concentration of 5 to 50% by weight. The compound of the present invention is different from Comparative Example A in the oxidation test such as DSC.
Low concentration of fluid in mixture (eg 5-20% by weight)
It gives a considerable oxidative stability effect in the mixture.

On the contrary, the compound of Comparative Example C having no hydrogen atom at the β-position with respect to the sulfur atom, when mixed as the composition K, gave almost no effect in this concentration range.

The fluid of Example 1 was added to the additive package A,
A lubricant composition containing a pour point depressant and a viscosity index improving polymer (Composition M) was mixed at 17% by weight. The remaining components to make the mixture 100% consisted of a hydrocarbon-based fluid. Table 4 shows the test results of this lubricant composition in the engine test (Sequence 3E test). The test (ASTM STP 315H Pt
II) was used to determine oxidation resistance as measured by viscosity increase, among other aspects of lubricant performance.

[0065]

[Table 5]

The results of this engine test on a lubricant composition containing the same concentrations of additive package A, pour point depressant and viscosity index improving polymer but mixed in a hydrocarbon basestock only (Composition L) were obtained. Included for comparison.

From the test results, it was found that the lubricant composition containing the compound of Example 1 significantly improved the oxidative stability in engine tests, as compared to a similar lubricant composition to which the compound of the invention was not added. I understand. The lubricant composition without the compound did not give satisfactory results in both tests, whereas the lubricant composition with the compound
There was little change in viscosity during the test.

The compounds of the present invention are polarised, for example by the carboxyester functionality. Among other aspects of lubricant performance, the polarity of the base fluid affects the behavior of elastomer seals in engines and machines. The compound of Example 1 containing two ester groups per molecule was esterified with an ethoxylated alcohol, thus changing the polarity of the molecule, Comparative Example D (2-
A comparison was made with a fluid of (2-ethoxyethoxy) ethyl-9 (10)-(carbobutoxymethylthio) stearate). Tests were performed using nitrile- and fluoro-elastomer rubbers in high performance gasoline engine lubricants CE
Performed according to CL-39-T-87. It should be noted that the fluid base in question was mixed at two different levels, namely 5% and 17% by weight. The results are shown in Table 5.

[0069]

[Table 6]

* Out of Specification The composition containing the compound of Example 1 passed all criteria for fluoro and nitrile seals at both concentrations of the compound, while the composition containing Comparative Example D contained 17% by weight of the compound. Hardness of fluoroelastomer containing 17
The criteria were not met in volume change and hardness for the nitrile elastomer with wt% compound and tensile strength for the nitrile elastomer with 5 wt% compound.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication location // C10N 30:10 40:25 (72) Inventor Harold Monklyev Gillespiet, Chester Sea, England・ H ・ 4 ・ 7 ・ R ・ Kyu ・ Vincent ・ Driving ・ 7 (72) Inventor Frederick William Haewtsd South Wilal El 64 ・ 1 ・ Tay Davryu, Uhrain, Laurel ・Drive 26 (72) Inventor Eugene Theraard Matsukenna Brighton 3186, Victoria, Australia, Dejurant Street 62

Claims (10)

[Claims] 1. The following formula: [In the formula, A is a hydrogen atom or an alkyl group; B is an alkyl group, a group of the formula CO ₂ -W (W is an alkyl group), or a formula Y-CO ₂ -Z (Y is an alkylene group. And Z is an alkyl group) or the formula C
H ₂ CH (CO ₂ D) CH ₂ CO ₂ E (D and E are each independently an alkyl group); R ′ and R ″ are each independently a hydrogen atom, an alkyl group, or C
H ₂ CO ₂ F (F is an alkyl group) group;
p is 0 to 40; X is a group of CO ₂ G (G is a C _1-30 alkyl group) or (CH ₂ ) _n CO ₂ J (J
Is C _1-10 alkyl group, n is 1 to 12. ), Provided that the formula S (CH ₂ CH ₂ CO ₂ R) ₂ or S (CH ₂ CO ₂ R) ₂ (R is an alkyl group).
Compounds of the formula _{CH 3 (CH 2) 8 -CH} (SCH 2 CO
_{2 L) - (CH 2)} 7 -CO 2 or K (K and L are each an octyl group, K is at L ethyl butyl group) of the compound, and the formula MO ₂ C-CH ₂ -CH (S
N) -CO ₂ M (M is a decyl group, N represents a compound of excluding dodecyl)], at least 440
A compound having a molecular weight of. 2. The compound according to claim 1, wherein A is a hydrogen atom or a C _1-30 alkyl group. 3. B is a C _1-30 alkyl group, or CO ₂ W
(W is a C _1-30 alkyl group.) Or Y-C
O ₂ —Z (Y is a C _1-30 alkylene group, Z is C _1-30
An alkyl group) or CH ₂ CH (CO
₂ D) CH ₂ CO ₂ E (D and E are each independently C
_{It is a 3-15} alkyl group. 3. The compound according to claim 1 or 2, which is a group of). 4. R ′ and R ″ are each independently a hydrogen atom, a C _1-10 alkyl group, or CH ₂ CO ₂ F.
(F is a _C3-15 alkyl group.) The compound of Claim 1, 2 or 3 characterized by the above-mentioned. 5. A compound according to claim 1, which comprises reacting an olefinically unsaturated compound with a sulfur-containing compound and, if necessary, esterifying the compound thus obtained. Manufacturing method. 6. The sulfur-containing compound is hydrogen sulfide, thiol,
The method according to claim 5, wherein the method is thiophenol or thiol acid. 7. A base fluid having the following formula: [In the formula, A is a hydrogen atom or an alkyl group; B is an alkyl group, a group of the formula CO ₂ -W (W is an alkyl group), or a formula Y-CO ₂ -Z (Y is an alkylene group. And Z is an alkyl group) or the formula C
H ₂ CH (CO ₂ D) CH ₂ CO ₂ E (D and E are each independently an alkyl group); R ′ and R ″ are each independently a hydrogen atom, an alkyl group, or C
H ₂ CO ₂ F (F is an alkyl group) group;
p is 0 to 40; X is a group of CO ₂ G (G is a C _1-30 alkyl group) or (CH ₂ ) _n CO ₂ J (J
Is C _1-10 alkyl group, n is 1 to 12. ), Provided that the formula S (CH ₂ CH ₂ CO ₂ R) ₂ or S (CH ₂ CO ₂ R) ₂ (R is an alkyl group).
Compounds of the formula _{CH 3 (CH 2) 8 -CH} (SCH 2 CO
₂ L) - (CH ₂₎ a compound of ₇ -CO ₂ K (K and L are each an octyl group), and the formula MO ₂ C-CH ₂
-CH (SN) -CO ₂ M (M is a decyl group and N is a dodecyl group)], and a compound having a molecular weight of at least 440 is included. Stuff. 8. The compound is 2-100 of the total base fluid.
The lubricating oil composition of claim 7, wherein the lubricating oil composition is present in an amount of weight percent. 9. The lubricating oil composition according to claim 8, wherein the balance of the total base fluid is a base oil derived from a mineral oil or a synthetic oil. 10. The following formula as a base fluid in a lubricating oil composition: [In the formula, A is a hydrogen atom or an alkyl group; B is an alkyl group, a group of the formula CO ₂ -W (W is an alkyl group), or a formula Y-CO ₂ -Z (Y is an alkylene group. And Z is an alkyl group) or the formula C
H ₂ CH (CO ₂ D) CH ₂ CO ₂ E (D and E are each independently an alkyl group); R ′ and R ″ are each independently a hydrogen atom, an alkyl group, or C
H ₂ CO ₂ F (F is an alkyl group) group;
p is 0 to 40; X is a group of CO ₂ G (G is a C _1-30 alkyl group) or (CH ₂ ) _n CO ₂ J (J
Is C _1-10 alkyl group, n is 1 to 12. Is a group of)).