阅读说明：本技术 一种酯类化合物及其制备方法、用途 (Ester compound and preparation method and application thereof ) 是由 张耀 段庆华 鱼鲲 李勇 于 2019-10-24 设计创作，主要内容包括：本发明提供了一种酯类化合物及其制备方法、用途。本发明的酯类化合物的结构为：其中各基团的定义见说明书。本发明的酯类化合物具有优异的黏温、低温、抗氧化、减摩性能。(The invention provides an ester compound and a preparation method and application thereof. The structure of the ester compound of the invention is as follows:)

1. An ester compound having the structure:

wherein each L is₁Each independently selected from the group consisting of H atom and a group represented by formula (II), and at least one L₁The group is selected from the group shown in the formula (II),

in the formula (II), m is an integer of 1 to 10 (preferably an integer of 1 to 6, more preferably an integer of 1 to 5); m + 1R groups, equal to or different from each other, are each independently selected from the group consisting of a single bond, C_1-10Alkylene (preferably C)_1-5Straight or branched alkylene, more preferably C_1-3Linear or branched alkylene); r₀The radicals, equal to or different from each other, are each independently selected from H, C_1-10Hydrocarbyl (preferably C)_1-5Straight or branched alkyl, more preferably C_1-3Straight or branched chain alkyl); m a groups, equal to or different from each other, are each independently selected from the group represented by formula (III), -C ═ C-, methylene, and ethylene, and at least one a group is selected from the group represented by formula (III);

in formula (III), the R' group is selected from C_1-17Hydrocarbyl (preferably C)_1-15Straight or branched alkyl, more preferably C_1-11Straight or branched chain alkyl);

L₂the radicals being selected from C_1-10A hydrocarbon group and a group (preferably selected from those represented by the formula (IV))From C_1-6Straight or branched chain alkyl and a group of formula (IV),

-R₁-O-L₁ (IV)

in the formula (IV), R₁The radicals being selected from C_1-10Alkylene (preferably C)_1-5Straight or branched alkylene, more preferably C_1-3Linear or branched alkylene); l is₁The group is selected from a H atom and a group represented by the formula (II) (the A group in the group represented by the formula (II) is selected from a group represented by the formula (III)).

2. An ester compound as claimed in claim 1, wherein the ester compound comprises one or more of the following compounds:

3. a preparation method of ester compounds comprises the step of reacting compounds shown as a formula (alpha) with compounds shown as a formula (beta),

in the formula (. alpha.), L₂The group being selected from C_1-10Hydrocarbyl or-R₁-OH (preferably selected from C)_1-6Straight or branched alkyl or-R₁-OH) wherein R is₁The radicals being selected from C_1-10Alkylene (preferably C)_1-5Straight or branched alkylene, more preferably C_1-3Linear or branched alkylene);

in the formula (β), m is an integer of 1 to 10 (preferably an integer of 1 to 6, more preferably an integer of 1 to 5); m + 1R groups, equal to or different from each other, are each independently selected from the group consisting of a single bond, C_1-10Alkylene (preferably C)_1-5Straight or branched alkylene, more preferably C_1-3Linear or branched alkylene); r₀The radicals, equal to or different from each other, are each independently selected from H, C_1-10Hydrocarbyl (preferably C)_1-5Straight or branched alkyl, more preferably C_1-3Straight or branched chain alkyl); the Y group is selected from H, F, Cl, Br and I; m A groups eachThe same or different, are each independently selected from groups of formula (γ), -C ═ C-, methylene, ethylene, and at least one a group is selected from groups of formula (γ);

in the formula (. gamma.), R₀The group being selected from C_1-17Hydrocarbyl (preferably C)_1-15Straight or branched alkyl, more preferably C_1-11Straight or branched chain alkyl).

4. A method according to claim 3, wherein the compound of formula (α) is one or more of the following specific compounds: trimethylolpropane, pentaerythritol.

5. A process according to claim 3, wherein the compound of formula (. beta.) is obtained by reacting a compound of formula (. delta.) with a compound of formula (. epsilon.),

R′₀-COOH (ε)

in the formula (δ), m is an integer of 1 to 10 (preferably an integer of 1 to 6, more preferably an integer of 1 to 5); m + 1R groups, equal to or different from each other, are each independently selected from the group consisting of a single bond, C_1-10Alkylene (preferably C)_1-5Straight or branched alkylene, more preferably C_1-3Linear or branched alkylene); r₀The radicals, equal to or different from each other, are each independently selected from H, C_1-10Hydrocarbyl (preferably C)_1-5Straight or branched alkyl, more preferably C_1-3Straight or branched chain alkyl); the Y group is selected from H, F, Cl, Br and I; m a 'groups, equal to or different from each other, are each independently selected from the formula-C ═ C-, methylene, ethylene, and at least one a' group is-C ═ C-;

in the formula (. epsilon.), R₀The group being selected from C_1-17Hydrocarbyl (preferably C)_1-15Straight or branched alkyl, more preferably C_1-11Straight or branched chain alkyl).

6. The method according to claim 5, wherein the equivalent ratio of the reaction between the compound represented by the formula (δ) (in-C ═ C-) and the compound represented by the formula (ε) (in the carboxyl group) is 0.05 to 20: 1 (preferably 0.1-10: 1); the reaction temperature is 0-200 ℃ (preferably 50-160 ℃); the reaction time is 0.5 to 72 hours (preferably 3 to 48 hours).

7. A process according to claim 5, wherein a catalyst is added to the reaction of the compound of formula (δ) with the compound of formula (ε) (the catalyst may be one or more of an inorganic acid, an organic acid, a solid acid, a heteropolyacid, an acidic ionic liquid, an acidic resin, an acidic molecular sieve, a metal chloride and a metal oxide, for example sulphuric acid, perchloric acid, AlCl may be used₃One or more of tin chloride, n-butyl tin oxide, dibutyl tin oxide, p-toluenesulfonic acid, acidic resins, phosphotungstic heteropoly acids, acidic ionic liquids, and acidic molecular sieves).

8. The method according to claim 5, wherein the compound represented by the formula (δ) is selected from one or more of the following compounds: eicosenoic acid, oleic acid, linoleic acid, linolenic acid, hexadecenoic acid, tetradecenoic acid, dodecenoic acid, undecenoic acid, decenoic acid, octenoic acid.

9. The method according to claim 5, wherein the compound of formula (ε) is selected from one or more of the following compounds: formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, pelargonic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, eicosenoic acid, oleic acid, linoleic acid, linolenic acid, hexadecenoic acid, arachidonic acid, dodecenoic acid, undecylenic acid, decenoic acid, octenoic acid.

10. A process according to claim 3, wherein the equivalent ratio of the reaction between the compound of formula (α) (in OH) and the compound of formula (β) (in Y) is from 0.1 to 10: 1 (preferably 0.2-5: 1); the reaction temperature is 70-250 ℃ (preferably 90-200 ℃); the reaction time is 0.5 to 24 hours (preferably 2 to 15 hours).

11. A process according to claim 3, wherein a catalyst is added to the reaction of the compound of formula (α) with the compound of formula (β) (the catalyst may be one or more of an inorganic acid, an organic acid, a solid acid, a heteropolyacid, an acidic ionic liquid, an acidic resin, an acidic molecular sieve, a metal chloride and a metal oxide, for example, sulphuric acid, perchloric acid, AlCl may be used₃One or more of tin chloride, n-butyl tin oxide, dibutyl tin oxide, p-toluenesulfonic acid, acidic resins, phosphotungstic heteropoly acids, acidic ionic liquids, and acidic molecular sieves, preferably one or more of sulfuric acid, tin chloride, n-butyl tin oxide, p-toluenesulfonic acid, acidic resins, and phosphotungstic heteropoly acids).

12. A lubricating oil composition comprising the ester compound of claim 1 or 2 or the ester compound prepared by the method of any one of claims 3 to 11, and a lubricating oil base oil.

13. Use of the ester compound of claim 1 or 2 or the ester compound prepared by the method of any one of claims 3 to 11 as one or more of a lubricating oil base oil, a lubricating oil viscosity index improver and a lubricating oil friction improver.

Technical Field

The invention relates to an ester compound, in particular to an ester compound which can be used as a lubricating oil additive or a lubricating oil base oil.

Background

Lubricating oil is an indispensable component in the operation of machinery, plays roles in reducing friction and wear, protecting machinery, cooling, cleaning, sealing, prolonging service life and the like, but because the factors such as lubricating oil leakage, overflow, evaporation or improper treatment and the like cause serious harm to the natural environment, higher requirements on the environmental friendliness of the lubricating oil are put forward. In the prior art, base oil and additives which form lubricating oil are mostly from petroleum raw materials, are difficult to regenerate under the specific time condition of the nature at the present stage, and the components are mostly isoparaffin, cycloparaffin, aromatic hydrocarbon and trace metal substances, which causes poor biodegradability.

The environmentally friendly lubricating oil means a lubricating oil having excellent biodegradability, renewability, and no toxicity or low toxicity. The degradation rate of environmentally friendly lubricating oils is typically more than two times higher than that of petroleum base oils.

The vegetable oil has the advantages of good lubricating property, wide raw material source, lower production cost, good biodegradability (the biodegradation rate can reach 70% -100%), and the like, is suitable for boundary lubrication, can be used for hydrodynamic lubrication, and can be applied to most lubrication working conditions. Compared with mineral oil, the vegetable oil has better lubricating property and viscosity-temperature property, the viscosity change of the vegetable oil is smaller in a wide temperature range, the friction can be better reduced, and the mechanical energy loss can be reduced by 5-15% compared with the mineral oil. The vegetable oil also has higher flash point and lower evaporation loss, can obviously reduce the overflow of organic gas under the high-temperature working condition, and is safer to use in the open environment. However, unsaturated double bonds in vegetable oil molecules are easily oxidized, so that the problems of viscosity increase, acid corrosion and the like are caused.

For this reason, many base oils and additives of ester structure have been developed in the prior art.

US 6051539 reports that the improvement of antioxidant and low temperature properties of vegetable oils is achieved by modifying the fatty side chain structure in the triglyceride structure of vegetable oils, comprising a two-step reaction: (1) carrying out esterification reaction on isomeric fatty acid (such as 2-ethyl hexanoic acid) and methanol or polyol containing branched chain to generate branched chain fatty acid methyl ester or polyol ester; (2) the branched fatty acid methyl ester or polyol ester and triglyceride are subjected to transesterification reaction under the action of a catalyst to generate triglyceride partially substituted by branched fatty acid and polyol ester partially substituted by long-chain fatty acid.

Although the existing ester base oil and additives can improve the environmental friendliness of the lubricating oil, there is a great room for improvement. With the development of environment-friendly lubricating oil, higher requirements are also put forward on the performance of ester base oil and additives. In view of this, there is still a need in the art for more excellent environmentally friendly base oils and additives.

Disclosure of Invention

The invention provides an ester compound and a preparation method and application thereof.

The structure of the ester compound of the invention is as follows:

wherein each L is₁Each independently selected from the group consisting of H atom and a group represented by formula (II), and at least one L₁The group is selected from the group shown in the formula (II),

in the formula (II), m is an integer of 1 to 10 (preferably an integer of 1 to 6, more preferably an integer of 1 to 5); m + 1R groups, equal to or different from each other, are each independently selected from the group consisting of a single bond, C_1-10Alkylene (preferably C)_1-5Straight or branched alkylene, more preferably C_1-3Linear or branched alkylene); r₀The radicals, equal to or different from each other, are each independently selected from H, C_1-10Hydrocarbyl (preferably C)_1-5Straight or branched alkyl, more preferably C_1-3Straight or branched chain alkyl); m A groups being mutually phase(III) each independently is selected from the group represented by formula (III), -C ═ C-, methylene, and ethylene, and at least one a group is selected from the group represented by formula (III);

in the formula (III), R₀The group being selected from C_1-17Hydrocarbyl (preferably C)_1-15Straight or branched alkyl, more preferably C_1-11Straight or branched chain alkyl);

L₂the radicals being selected from C_1-10A hydrocarbon group and a group of the formula (IV) (preferably selected from C)_1-6Straight or branched chain alkyl and a group of formula (IV),

-R₁-O-L₁ (IV)

in the formula (IV), R₁The radicals being selected from C_1-10Alkylene (preferably C)_1-5Straight or branched alkylene, more preferably C_1-3Linear or branched alkylene); l is₁The group is selected from a H atom and a group represented by the formula (II) (the A group in the group represented by the formula (II) is selected from a group represented by the formula (III)).

The ester compound with a specific structure comprises one or more of the following compounds:

the invention also provides a preparation method of the ester compound, which comprises the step of reacting the compound shown in the formula (alpha) with the compound shown in the formula (beta),

in the formula (. alpha.), L₂The group being selected from C_1-10Hydrocarbyl or-R₁-OH (preferably selected from C)_1-6Straight or branched alkyl or-R₁-OH) wherein R is₁The radicals being selected from C_1-10Alkylene (preferably C)_1-5Straight or branched alkylene, more preferably C_1-3Linear or branched alkylene);

in the formula (β), m is an integer of 1 to 10 (preferably an integer of 1 to 6, more preferably an integer of 1 to 5); m + 1R groups, equal to or different from each other, are each independently selected from the group consisting of a single bond, C_1-10Alkylene (preferably C)_1-5Straight or branched alkylene, more preferably C_1-3Linear or branched alkylene); r₀The radicals, equal to or different from each other, are each independently selected from H, C_1-10Hydrocarbyl (preferably C)_1-5Straight or branched alkyl, more preferably C_1-3Straight or branched chain alkyl); the Y group is selected from H, F, Cl, Br and I; m a groups, equal to or different from each other, are each independently selected from the group represented by formula (γ), -C ═ C-, methylene, ethylene, and at least one a group is selected from the group represented by formula (γ);

in the formula (. gamma.), R₀The group being selected from C_1-17Hydrocarbyl (preferably C)_1-15Straight or branched alkyl, more preferably C_1-11Straight or branched chain alkyl).

According to the invention, the compound of formula (α) may be selected from one or more of the following specific compounds: trimethylolpropane, pentaerythritol.

According to the invention, alternatively, the compound represented by the formula (. beta.) can be obtained by reacting a compound represented by the formula (. delta.) with a compound represented by the formula (. epsilon.),

in the formula (δ), m is an integer of 1 to 10 (preferably an integer of 1 to 6, more preferably an integer of 1 to 5); m + 1R groups, equal to or different from each other, are each independently selected from the group consisting of a single bond, C_1-10Alkylene (preferably C)_1-5Straight or branched alkylene, more preferably C_1-3Linear or branched alkylene); r₀The radicals, equal to or different from each other, are each independently selected from H, C_1-10Hydrocarbyl (preferably C)_1-5Straight or branched alkyl, more preferably C_1-3Straight or branched chain alkyl); the Y group is selected from H, F, Cl, Br and I; m A' groups, equal to or different from each other, each independentlyIs selected from the formula-C ═ C-, methylene, ethylene, and at least one a' group is-C ═ C-; in the formula (. epsilon.), R₀The group being selected from C_1-17Hydrocarbyl (preferably C)_1-15Straight or branched alkyl, more preferably C_1-11Straight or branched chain alkyl).

According to the present invention, the reaction equivalent ratio between the compound represented by the formula (δ) (in terms of-C ═ C-) and the compound represented by the formula (∈) (in terms of carboxyl groups) is preferably 0.05 to 20: 1, more preferably 0.1 to 10: 1; the reaction temperature is preferably 0-200 ℃, and more preferably 50-160 ℃; the reaction time is preferably 0.5 to 72 hours, more preferably 3 to 48 hours.

According to the present invention, a solvent may or may not be added, preferably a solvent is added, in the reaction of the compound represented by the formula (δ) and the compound represented by the formula (ε). The solvent is preferably a hydrocarbon solvent, preferably one or more of alkane, aromatic hydrocarbon and ether, more preferably an alkane solvent, and for example, one or more of hexane, heptane, octane, nonane, decane, cyclohexane, cycloheptane, cyclooctane, cyclononane, cyclodecane, benzene, toluene, xylene, ethylbenzene, propylbenzene, diethyl ether, propyl ether, isopropyl ether and dibutyl ether may be used. The amount of the solvent to be added is not particularly limited, as long as the reaction is promoted to proceed smoothly.

According to the present invention, a catalyst may or may not be added to the reaction of the compound represented by the formula (δ) with the compound represented by the formula (ε). The catalyst can be one or more of inorganic acid, organic acid, solid acid, heteropoly acid, acidic ionic liquid, acidic resin, acidic molecular sieve, metal chloride and metal oxide, for example, sulfuric acid, perchloric acid, AlCl can be selected₃One or more of stannic chloride, n-butyl stannic oxide, dibutyl stannic oxide, p-toluenesulfonic acid, acidic resins, phosphotungstic heteropoly acids, acidic ionic liquids and acidic molecular sieves, preferably one or more of perchloric acid, stannic chloride, n-butyl stannic oxide, p-toluenesulfonic acid, acidic resins and phosphotungstic heteropoly acids. The amount of the catalyst to be added is preferably 0.1 to 10% by mass based on the compound represented by the formula (δ).

According to the invention, the compound represented by the formula (δ) may be selected from one or more of the following specific compounds: eicosenoic acid, oleic acid, linoleic acid, linolenic acid, hexadecenoic acid, tetradecenoic acid, dodecenoic acid, undecenoic acid, decenoic acid, octenoic acid.

According to the invention, the compound of formula (ε) may be selected from one or more of the following specific compounds: formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, pelargonic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, eicosenoic acid, oleic acid, linoleic acid, linolenic acid, hexadecenoic acid, arachidonic acid, dodecenoic acid, undecylenic acid, decenoic acid, octenoic acid.

According to the invention, the reaction equivalent ratio between the compound represented by the formula (alpha) (calculated as OH) and the compound represented by the formula (beta) (calculated as Y) is preferably 0.1-10: 1, more preferably 0.2 to 5: 1; the reaction temperature is preferably 70-250 ℃, and more preferably 90-200 ℃; the reaction time is preferably 0.5 to 24 hours, more preferably 2 to 15 hours.

According to the present invention, a solvent may be added or may not be added, preferably a solvent is added in the reaction of the compound represented by the formula (α) and the compound represented by the formula (β). The solvent is preferably a hydrocarbon solvent, preferably one or more of alkane, aromatic hydrocarbon and ether, more preferably an alkane solvent, and for example, one or more of hexane, heptane, octane, nonane, decane, cyclohexane, cycloheptane, cyclooctane, cyclononane, cyclodecane, benzene, toluene, xylene, ethylbenzene, propylbenzene, diethyl ether, propyl ether, isopropyl ether and dibutyl ether may be used. The amount of the solvent to be added is not particularly limited, as long as the reaction is promoted to proceed smoothly. The solvent can also play a role of a water carrying agent so as to promote the smooth proceeding of the reaction.

According to the present invention, a catalyst may or may not be added in the reaction of the compound represented by the formula (α) and the compound represented by the formula (β). The catalyst can be one or more of inorganic acid, organic acid, solid acid, heteropoly acid, acidic ionic liquid, acidic resin, acidic molecular sieve, metal chloride and metal oxide, and can be selected from sulfuric acid, perchloric acid, etc,AlCl₃One or more of tin chloride, n-butyl tin oxide, dibutyl tin oxide, p-toluenesulfonic acid, acidic resins, phosphotungstic heteropoly acids, acidic ionic liquids and acidic molecular sieves, preferably one or more of sulfuric acid, tin chloride, n-butyl tin oxide, p-toluenesulfonic acid, acidic resins and phosphotungstic heteropoly acids. The amount of the catalyst to be added is preferably 0.1 to 10% by mass based on the compound represented by the formula (. beta.). The catalyst may be removed by a method known in the art (e.g., a method of alkali washing and water washing), and is not particularly limited.

According to the present invention, in the reaction of the compound represented by the formula (α) and the compound represented by the formula (β), the reaction product is preferably washed and purified with a solvent, and the solvent which can be washed is preferably a hydrocarbon solvent. The solvent may be removed by conventional techniques such as drying, evaporation, distillation, and the like.

According to the present invention, the reaction of the compound represented by the formula (. alpha.) with the compound represented by the formula (. beta.) may be carried out in a continuous or batch reaction apparatus such as a reaction vessel, a fixed bed, a fluidized bed, a microchannel reactor, etc.

The invention also provides a lubricating oil composition which comprises the ester compound or the ester compound prepared by the method and lubricating oil base oil. Wherein the mass fraction of the ester compound in the lubricating oil composition is 0.1-100%, preferably 0.1-90%, more preferably 1-50%, further optionally 2-30%, 0.5-5%.

According to the present invention, the lubricating oil composition may further comprise other components. Examples of the other components include various additives which are allowed to be added to the lubricating oil composition in the art, and specific examples thereof include phenol type, amine type or sulfur phosphorus type antioxidants, carboxylate, sulfonate or alkylphenate detergents, succinimide type ashless dispersants, polyester, polyolefin or alkylnaphthalene type pour point depressants, methacrylate ester copolymers, ethylene-propylene copolymers, polyisobutylene, hydrogenated styrene/butadiene copolymer type viscosity index improvers, sulfur/phosphorus type friction modifiers, sulfur/phosphorus and boric acid type extreme pressure agents, and silicon type or non-silicon type antifoaming agents. The kind and amount of these additives are well known to those skilled in the art and will not be described herein. These additives may be used singly or in combination in any ratio.

The invention also provides one or more applications of the ester compound as lubricating oil base oil, lubricating oil viscosity index improver and lubricating oil friction improver.

The ester compound has excellent viscosity temperature, low temperature, oxidation resistance and antifriction performance.

The ester compound disclosed by the invention has excellent viscosity-temperature performance and low-temperature performance as base oil, has excellent viscosity-temperature performance and low-temperature performance as a viscosity index improver, can be used as an antiwear agent to obviously reduce the wear-scar diameter of the base oil, and can be used as a friction improver to obviously reduce the friction coefficient of the base oil.

Detailed Description

In the context of the present specification, the term "single bond" is sometimes used in the definition of a group. By "single bond", it is meant that the group is absent. For example, assume the formula-CH₂-A-CH₃Wherein the group a is defined as being selected from the group consisting of a single bond and a methyl group. In this respect, if A is a single bond, this means that the group A is absent, in which case the formula is correspondingly simplified to-CH₂-CH₃。

In the context of the present specification, the expression "number + valence + group" or the like refers to a group obtained by removing the number of hydrogen atoms represented by the number from the basic structure (such as a chain, a ring, a combination thereof, or the like) to which the group corresponds, and preferably refers to a group obtained by removing the number of hydrogen atoms represented by the number from a carbon atom (preferably a saturated carbon atom and/or a non-identical carbon atom) contained in the structure. For example, "3-valent straight or branched alkyl" refers to a group obtained by removing 3 hydrogen atoms from a straight or branched alkane (i.e., the base chain to which the straight or branched alkyl corresponds), and "2-valent straight or branched heteroalkyl" refers to a group obtained from a straight or branched heteroalkane (preferably from the carbon atoms contained in the heteroalkane,or further, from a non-identical carbon atom) by removing 2 hydrogen atoms. For example, the 2-valent propyl group may be-CH₂-CH₂-CH₂-*、The 3-valent propyl group may beThe 4-valent propyl group may beWherein represents a binding end in the group that may be bonded to other groups.

Example 1: preparation of isomerate A

The reaction was carried out in a high pressure autoclave equipped with a vent, stirrer and thermocouple. 565g of oleic acid was gradually pumped into a reaction vessel containing 1200g of acetic acid and 10g of 70% perchloric acid, reacted at 70 ℃ for 24 hours, heating was stopped, the reaction was completed, the remaining acetic acid was removed by distillation, the reaction vessel was cooled to room temperature, washed with alkali, washed with water and the organic phase with potassium dihydrogen phosphate having a pH of 3.7 three times, dried over anhydrous sodium sulfate, filtered, etc., and unreacted oleic acid was removed by molecular distillation to obtain an acetic acid-oleic acid adduct, i.e., an isomerized acid a, whose structure is shown below.

Example 2: preparation of ester Compound A-1

Adding 171g of isoacid A, 22g of trimethylolpropane, 1.8g of p-toluenesulfonic acid catalyst and water carrying agent (petroleum ether at 90-120 ℃) into a 500mL three-neck glass flask, heating to reflux temperature, and collecting H generated in the reaction process by using a water separator₂And O, stopping the reaction until the actual water yield is the same as the theoretical value. And (3) washing the crude product with alkali to remove the catalyst, washing with water to neutrality, and removing the reaction solvent to obtain the ester compound A-1.

Example 3: preparation of ester Compound A-2

Adding 171g of isoacid A, 17g of pentaerythritol, 1.8g of p-toluenesulfonic acid catalyst and water carrying agent (petroleum ether at 90-120 ℃) into a 500mL three-neck glass flask, heating to reflux temperature, and collecting H generated in the reaction process by using a water separator₂And O, stopping the reaction until the actual water yield is the same as the theoretical value. And (3) washing the crude product with alkali to remove the catalyst, washing with water to neutrality, and removing the reaction solvent to obtain the ester compound A-2.

Example 4: preparation of ester Compound A-3

Adding 67g of trimethylolpropane, 0.5g of p-toluenesulfonic acid catalyst and toluene serving as a water carrying agent into a 500mL three-neck glass flask, heating to reflux temperature, gradually dropwise adding 85g of isoacid A into the three-neck glass flask within 3H, and collecting H generated in the reaction process by using a water separator₂And O, stopping the reaction when the actual water yield is the same as the theoretical value, and distilling to remove the excessive trimethylolpropane. And (3) washing the crude product with alkali to remove the catalyst, washing with water to neutrality, and removing the reaction solvent to obtain the ester compound A-3.

Comparative example 1: preparation of ester Compound D-1

D-1 was prepared in the same manner as A-1 except that the isomeric acid A was replaced with an equimolar amount of oleic acid.

Comparative example 2: preparation of ester Compound D-2

D-2 was prepared in the same manner as A-1 except that trimethylolpropane was replaced with an equimolar amount of glycerol.

Example 5: preparation of isomeric acid B

The reaction was carried out in a high pressure autoclave equipped with a vent, stirrer and thermocouple. 560g of linoleic acid are pumped into a reaction kettle containing 1800g of acetic acid and 10g of 70% perchloric acid, reacted at 70 ℃ for 18 hours, heating is stopped, the reaction is ended, the residual acetic acid is removed by distillation, the reaction kettle is cooled to room temperature, washed by alkali, washed by water and washed by organic phase three times by potassium dihydrogen phosphate with Ph of 3.7, dried by anhydrous sodium sulfate and filtered, and unreacted linoleic acid is removed by molecular distillation, thus obtaining an addition product, namely, an isoacid B of acetic acid and linoleic acid, the structure of which is shown below.

Example 6: preparation of ester Compound B-1

Adding 201g of isoacid B, 22g of trimethylolpropane, 3.2g of p-toluenesulfonic acid catalyst and water carrying agent (petroleum ether at 90-120 ℃) into a 500mL three-neck glass flask, heating to reflux temperature, and collecting H generated in the reaction process by using a water separator₂And O, stopping the reaction until the actual water yield is the same as the theoretical value. And (3) washing the crude product with alkali to remove the catalyst, washing with water to neutrality, and removing the reaction solvent to obtain the ester compound B-1.

Example 7: preparation of ester Compound B-2

Adding 121g of isoacid B, 10g of pentaerythritol, 2.5g of p-toluenesulfonic acid catalyst and water carrying agent (petroleum ether at 90-120 ℃) into a 250mL three-neck glass flask, heating to reflux temperature, and collecting H generated in the reaction process by using a water separator₂And O, stopping the reaction until the actual water yield is the same as the theoretical value. And (3) washing the crude product with alkali to remove the catalyst, washing with water to neutrality, and removing the reaction solvent to obtain the ester compound B-2.

Example 8: preparation of ester Compound B-3

134g of trimethylolpropane, 2g of p-toluenesulfonic acid catalyst and toluene as a water carrying agent are added into a 500mL three-neck glass flask, the flask is heated to the reflux temperature, 201g of isoacid B is gradually dripped into the three-neck flask within 5H, and H generated in the reaction process is collected by a water separator₂And O, stopping the reaction when the actual water yield is the same as the theoretical value, and distilling to remove the excessive trimethylolpropane. And (3) washing the crude product with alkali to remove the catalyst, washing with water to neutrality, and removing the reaction solvent to obtain the ester compound B-3.

Comparative example 3: preparation of ester compound DM-1

The preparation method of DM-1 is the same as B-1 except that trimethylolpropane is replaced by ethanol with the same mole, and the ester compound DM-1 is obtained.

The physical and chemical properties of the ester compounds of examples A-1 to A-3, B-1 to B-2, D-1 and D-2 were examined by GB/T265 petroleum product kinematic viscosity determination method and dynamic viscometer algorithm, GB/T1995 petroleum product viscosity index calculation method, GB/T3535 petroleum product pour point determination method, SH/T0074 gasoline engine oil thin layer oxygen absorption oxidation stability test method, and the results are shown in Table 1.

TABLE 1

The ester compounds of examples A-3, B-3 and DM-1 were examined for their anti-wear properties by the SH/T0762 method for measuring the friction coefficient of lubricating oil (four-ball method), the results of which are shown in Table 2.

TABLE 2

Sample (I)	Steel ball grinding spot diameter/mum
		A-3	331
B-3	285
		DM-1	585

The above embodiments are only used to illustrate the technical solutions of the embodiments of the present disclosure, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present disclosure.