CN115960650A - Lubricating oil composition for air compressor and preparation method thereof - Google Patents

Abstract

The invention provides an air compressor lubricating oil composition, which comprises, by mass, 0.1-10% of an organic boron compound, 0.01-5% of an antioxidant, 0.01-5% of an extreme pressure antiwear agent, 0.001-1% of a defoaming agent and a main amount of ester lubricating base oil, wherein the organic boron compound has a structure shown in formula (I):

Description

Air compressor lubricating oil composition and preparation method thereof

Technical Field

The invention relates to a lubricating oil, in particular to an air compressor lubricating oil composition and a preparation method thereof.

Background Art

Air compressor is a general-purpose mechanical equipment that can provide power and process gas and is widely used in the industry. With the development of air compressor technology, higher requirements are placed on the performance of air compressor lubricants. For recycled air compressor lubricants, it is necessary to have stronger resistance to high temperature oxidation and extreme pressure and anti-wear properties. Compared with mineral air compressor lubricants, synthetic air compressor oils have the advantages of good high and low temperature performance, long service life, high cost performance, improved compressor operation safety factor, less environmental pollution, etc., and can better adapt to the use and needs of new compressors, but there are also problems such as short oil change cycle and poor resistance to high temperature oxidation.

In air compressor lubricating oil, the antioxidants used mainly include phenol type, amine type, phenol ester type, thioester type, phosphite type, etc., among which hindered phenol type antioxidants are widely used. For example, CN 113088368, CN 92102699, CN 99811367, USP 5124057, USP 6207623, USP 6410490, etc. all use hindered phenol type antioxidants as one of their antioxidant components, but it is difficult to meet the requirements of long life by using general hindered phenol type antioxidants. Therefore, the prior art still needs an air compressor lubricating oil composition with long life and excellent oxidation stability and anti-wear performance.

Summary of the invention

The invention provides an air compressor lubricating oil composition and a preparation method thereof. The air compressor lubricating oil composition has excellent high-temperature anti-oxidation performance and anti-wear performance.

The air compressor lubricating oil composition of the present invention comprises, by mass percentage, 0.1% to 10% of an organic boron compound, 0.01% to 5% of an antioxidant, 0.01% to 5% of an extreme pressure anti-wear agent, 0.001% to 1% of a defoaming agent, and a major amount of an ester lubricating base oil, wherein the structure of the organic boron compound is as shown in formula (I):

In formula (I), there are a repeating unit L and b boron-containing groups, a is an integer between 1 and 10 (preferably an integer between 1 and 5), b is an integer between 1 and 5 (preferably an integer between 1 and 3), and a L groups are the same or different and are independently selected from the group represented by formula (II);

式(III)所示的基团和式(IV)所示的基团，In formula (II), HO is bonded to the benzene ring (HO is preferably located at the meta position of the chain where R ₁ is located on the benzene ring); y R groups are bonded to the benzene ring; y is selected from an integer between 0 and 4 (preferably an integer between 1 and 3); the R groups are each independently selected from H and C _1-20 straight or branched alkyl (preferably each independently selected from H and C _1-4 straight or branched alkyl, more preferably tert-butyl); n is an integer between 1 and 10 (preferably an integer between 1 and 3); R ₁ is each independently selected from a single bond and a C _1-20 straight or branched alkylene (preferably selected from a single bond and a C _1-4 straight or branched alkylene); R ₂ in the n repeating units are the same or different from each other and are each independently selected from a single bond and a C _1-20 straight or branched alkylene (preferably each independently selected from a single bond and a C _1-4 straight or branched alkylene); R ₃ is selected from H and a C _1-20 straight or branched alkyl (preferably selected from H and C _1-4 straight or branched alkyl groups); the A groups in the n repeating units are the same or different from each other and are independently selected from a single bond,

The group represented by formula (III) and the group represented by formula (IV),

The _R4 groups are each independently selected from H and _C1-20 straight or branched alkyl (preferably selected from H and _C1-4 straight or branched alkyl);

m is an integer between 0 and 10 (preferably an integer between 1 and 5);

The R ₅ groups are each independently selected from a trivalent C _1-20 straight chain or branched chain alkyl group (preferably each independently selected from a trivalent C _1-4 straight chain or branched chain alkyl group);

Each _G2 group is independently selected from the group bonded to the _G4 group present in the other L group other than the L group in which it is located, a _C1-10 straight or branched alkyl group, _-R6G3 , _and H; each _G3 group is independently selected from _-OG1 , a _C1-10 straight or branched alkyl group, and H (preferably, independently selected from _-OG1 , a _C1-4 straight or branched alkyl group, OH, and H);

The R ₆ groups are selected from C _1-20 straight or branched alkylene groups (preferably each independently selected from C _1-4 straight or branched alkylene groups);

The _G1 group is selected from the binding end bonded to the boron-containing group, H;

The _G4 group is selected from the binding end bonded to the _G2 group present in other L groups other than the L group in which it is located, H;

Among a L groups, at least one A group is selected from the group represented by formula (III), and at least one _G1 group is selected from the binding end bonded to the boron element in the boron-containing group;

Each A' group in the b boron-containing groups is independently selected from the binding end bonded to the _G1 group present in the L group, the group represented by formula (V), -OR', and the R' group is H or a C _1-20 straight or branched alkyl group (preferably H or a C _1-4 straight or branched alkyl group);

In formula (V), m is an integer between 0 and 10 (preferably an integer between 1 and 5);

The R ₀ groups are each independently selected from C _1-10 straight or branched alkyl, -R ₆ G ₅ , H (preferably each independently selected from C _1-4 straight or branched alkyl, -R ₆ G ₅ , H);

The R ₅ groups are each independently selected from a trivalent C _1-20 straight chain or branched chain alkyl group (preferably each independently selected from a trivalent C _1-4 straight chain or branched chain alkyl group);

The _G6 group is selected from _{-R6G5 , C1-4} straight or branched alkyl, H;

The R ₆ groups are selected from C _1-20 straight or branched alkylene groups (preferably each independently selected from C _1-4 straight or branched alkylene groups);

Each G ₅ group is independently selected from -OG ₁ , C _1-4 straight or branched alkyl, OH, H, wherein the G ₁ group is selected from the binding end bonded to the boron element in the boron-containing group, C _1-4 straight or branched alkyl, H;

In the group represented by formula (V), there is at least one _G1 group selected from the binding end bonded to the boron element in the boron-containing group;

Among the b said boron-containing groups, at least one A' group is selected from the binding end bonded to the _G1 group present in the L group;

Each group in the organic boron compound complies with the bonding rules.

According to the present invention, the two binding ends in formula (III) or formula (IV) that are bonded to formula (II) can be bonded to the groups in formula (II) in any manner, for example, they can be bonded to formula (II) in one direction or in the opposite direction.

According to the present invention, examples of the organoboron compound include one or more of the following structural compounds:

The R group is H or a C ₁ -C ₂₀ straight or branched chain alkyl group.

According to the present invention, the method for preparing the organic boron compound comprises the following steps:

(1) reacting a compound represented by formula (X) with a peroxide;

其中所述的R₄基团各自独立地选自H和C_1-20直链或支链烷基(优选选自H和C_1-4直链或支链烷基)；在式(X)中至少存在一个A”为

In formula (X), HO is bonded to the benzene ring (HO is preferably located at the meta position of the chain where R ₁ is located on the benzene ring); y R groups are bonded to the benzene ring; y is selected from an integer between 0 and 4 (preferably an integer between 1 and 3); the R groups are each independently selected from H and C _1-20 straight or branched alkyl (preferably each independently selected from H and C _1-4 straight or branched alkyl, more preferably selected from tert-butyl); n is an integer between 1 and 10 (preferably an integer between 1 and 3); R ₁ is each independently selected from a single bond and a C _1-20 straight or branched alkylene (preferably selected from a single bond and a C _1-4 straight or branched alkylene); R ₂ in the n repeating units are the same or different from each other and are each independently selected from a single bond and a C _1-20 straight or branched alkylene (preferably each independently selected from a single bond and a C _1-4 straight or branched alkylene); R ₃ is selected from H and C _1-20 straight or branched chain alkyl groups (preferably selected from H and C _1-4 straight or branched chain alkyl groups); A" in the n repeating units are the same or different from each other and are independently selected from single bonds,

wherein the _R4 groups are independently selected from H and _C1-20 straight chain or branched alkyl (preferably selected from H and _C1-4 straight chain or branched alkyl); in formula (X), at least one A" is

(2) reacting the reaction product of step (1) with a compound represented by formula (Y);

In formula (Y), m is an integer between 0 and 10 (preferably an integer between 1 and 5);

The R ₀ 'groups are each independently selected from C _1-10 straight or branched alkyl, -R ₆ OH, H (preferably each independently selected from C _1-4 straight or branched alkyl, -R ₆ OH, H); the R ₅ groups are each independently selected from trivalent C _1-20 straight or branched alkyl (preferably each independently selected from trivalent C _1-4 straight or branched alkyl); each G ₅ 'group is each independently selected from C _1-4 straight or branched alkyl, OH, H; the G ₆ 'group is selected from C _1-10 straight or branched alkyl, -R ₆ OH, H; the R ₆ groups are each independently selected from C _1-20 straight or branched alkylene (preferably each independently selected from C _1-4 straight or branched alkylene);

In formula (Y), there is at least one G ₅ 'group selected from OH or at least one G ₆ 'group or R ₀ 'group selected from -R ₆ OH, and at least one R ₀ 'group or G ₆ 'group is H;

(3) reacting the reaction product of step (2) with an inorganic boron compound and collecting the product.

According to the present invention, in step (1), the compound represented by formula (X) can be selected from cardanol and alkylated cardanol. The alkylated cardanol can be obtained by reacting cardanol with an alkylating agent, for example, tert-butyl cardanol can be obtained by reacting cardanol with tert-butyl chloride.

According to the present invention, in step (1), the peroxide is preferably one or more of hydrogen peroxide, performic acid, peracetic acid, persulfonic acid, m-chloroperbenzoic acid, tert-butyl hydroperoxide, tert-butyl peracetate, methyl ethyl ketone peroxide, dibenzoyl peroxide and cyclohexanone peroxide, more preferably one or more of hydrogen peroxide, formic acid peroxide, peracetic acid and persulfonic acid.

According to the present invention, in step (2), the compound represented by formula (Y) can be selected from one or more of aliphatic amines, polyene polyamines, aliphatic amines substituted with one or more hydroxy groups, polyene polyamines substituted with one or more hydroxy groups, for example, one or more of ethanolamine, diethanolamine, hydroxyethylethylenediamine (i.e., N-(2-hydroxyethyl)ethylenediamine), diethylenetriamine, triethylenetetramine, tetraethylenepentamine and pentaethylenehexamine can be selected.

According to the present invention, in step (3), the inorganic boron compound is preferably selected from one or more of boric acid, boric oxide and boric acid half ester. The boric acid half ester can be selected from monoalkyl borate or dialkyl borate, wherein the alkyl group is a C ₁ -C ₂₀ straight chain or branched chain alkyl group.

According to the present invention, the equivalent ratio of the compound represented by formula (X) to the peroxide, the compound represented by formula (Y), and the inorganic boron compound is preferably 1:0.5-10:0.5-10:0.5-5, and more preferably 1:2-3:2-3:1-2.

According to the present invention, the reaction temperature of step (1) is preferably 0-100°C, more preferably 20-80°C; the reaction temperature of step (2) is preferably 50-150°C, more preferably 60-100°C; the reaction temperature of step (3) is preferably 80-200°C, more preferably 110-150°C.

According to the present invention, the reaction time of step (1), step (2) and step (3) is usually as long as possible. Generally speaking, the reaction time of step (1) is preferably 1 to 10 hours, more preferably 3 to 5 hours; the reaction time of step (2) is preferably 1 to 10 hours, more preferably 2 to 4 hours; the reaction time of step (3) is preferably 1 to 10 hours, more preferably 3 to 5 hours.

According to the present invention, in the reaction of step (3), a compound represented by formula (Y) may also be added, and the equivalent ratio between the compound represented by formula (Y) and the inorganic boron compound is preferably 1:0.5-5, more preferably 1:0.8-3.

According to the present invention, the reaction steps (1), (2) or (3) may be carried out in the presence of a diluent and/or a solvent, or may be carried out without using a diluent and/or a solvent.

According to the present invention, the diluent can be selected from one or more of API I, II, III, IV and V base oils. Common products or brands include 150SN, 200SN, 350SN, 500SN, 650SN, 150BS, HVI-100, HVI-150, HVI-200, HVI-350, HVI-400, HVI-500, HVI-150BS, PAO4, PAO6, PAO8, PAO10, alkylbenzene, alkylnaphthalene, etc.

According to the present invention, the solvent can be selected from C _6-20 aromatic hydrocarbons (such as benzene, toluene, xylene and isopropylbenzene), C _6-10 alkanes (such as n-hexane, cyclohexane and petroleum ether), solvent gasoline, etc. These solvents can be used alone or in combination of two or more. After the reaction is completed, the solvent can be removed by a method known to those skilled in the art, such as distilling the solvent under normal pressure or reduced pressure.

According to a particular embodiment of the present invention, the diluent and/or solvent may be added at any stage of the reaction step according to conventional amounts in the art, without particular limitation.

According to the present invention, it is obvious that the reaction step is generally carried out under the protection of an inert gas atmosphere. Examples of the inert gas include nitrogen and argon, etc., without particular limitation.

According to the present invention, in step (3), a promoter may be added to promote the completion of the reaction. Common promoters include water, ethanol, propanol, butanol, ammonia, etc. If a promoter is added, it can be removed after the reaction by a method known to those skilled in the art, such as distillation under normal pressure or reduced pressure.

According to the present invention, by the aforementioned method for preparing an organoboron compound, as a reaction product, a single organoboron compound can be produced, a mixture consisting of a plurality of organoboron compounds can also be produced, or a mixture consisting of one or more of the organoboron compounds and the aforementioned diluent (if used). These reaction products are all expected by the present invention, and the difference in their existence forms does not affect the realization of the effect of the present invention. Therefore, in the context of this specification, these reaction products are all collectively referred to as organoboron compounds without distinction. In view of this, according to the present invention, there is no absolute necessity to further purify the reaction product, or to further separate an organoboron compound of a certain structure from the reaction product. Of course, the purification or separation is preferred for further improvement of the expected effect of the present invention, but is not necessary for the present invention. Nevertheless, as the purification or separation method, for example, the reaction product can be purified or separated by a column chromatography method or a preparative chromatography method.

The organic boron compound of the invention has excellent antioxidant performance and anti-wear and friction-reducing performance.

According to the present invention, the antioxidant is preferably selected from phenolic antioxidants, for example, one or more of 2,6-di-tert-butyl-p-cresol, 2,6-di-tert-butyl mixed esters, 4,4-methylenebis(2,6-di-tert-butylphenol) and 2,6-di-tert-butyl-α-dimethylamino-p-cresol can be selected. Common trade names include T501, T512, BHT, etc.

According to the present invention, the extreme pressure anti-wear agent is preferably selected from one or more of thiophosphoric acid nitrogen-containing derivatives, phosphates, phosphites, thiophosphoric acid amine salts, sulfided olefins and dialkyl dithiocarbamates. For example, one or more of thiophosphoric acid nitrogen-containing derivatives, di-n-butyl phosphite, tricresyl phosphate, triethyl phosphate, thiophosphoric acid amine salts, sulfided isobutylene and zinc dibutyl dithiocarbamate can be selected. Common trade names include T304, T305, T306, T307, T321, etc.

According to the present invention, the defoaming agent is preferably selected from one or more of a copolymer of acrylic acid and ether, methyl silicone oil and ethyl silicone oil. Common trade names include T911, T912, T901 and the like.

According to the present invention, the ester lubricating base oil is preferably a diester lubricating base oil, for example, diisooctyl sebacate, diisooctyl adipate, etc. may be selected.

According to the present invention, preferably, the air compressor lubricating oil composition comprises, by mass percentage, 0.2% to 5% of an organic boron compound, 0.01% to 3% of an antioxidant, 0.01% to 3% of an extreme pressure anti-wear agent, 0.001% to 0.5% of a defoaming agent and a major amount of an ester lubricating base oil.

The method for preparing the air compressor lubricant composition of the present invention comprises the step of mixing the additives in the air compressor lubricant composition and the lubricant base oil. The mixing temperature is preferably 40° C. to 90° C., and the mixing time is preferably 1 hour to 6 hours.

The air compressor lubricating oil composition of the present invention has excellent high-temperature anti-oxidation performance and anti-wear performance, and can meet the requirements of a long-life air compressor lubricating oil composition.

DETAILED DESCRIPTION

In this specification, the term "single bond" is sometimes used in the definition of a group. The so-called "single bond" means that the group does not exist. For example, assuming the structural formula -CH ₂ -A-CH ₃ , where the group A is defined as being selected from a single bond and a methyl group. In view of this, if A is a single bond, it means that the group A does not exist, and the structural formula is correspondingly simplified to -CH ₂ -CH ₃ .

In the context of this specification, the expression "number + valence + group" or similar expressions 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 or a combination thereof) corresponding to the group, preferably refers to a group obtained by removing the number of hydrogen atoms represented by the number from the carbon atoms (preferably saturated carbon atoms and/or non-identical carbon atoms) contained in the structure. For example, "trivalent straight or branched alkyl" refers to a group obtained by removing 3 hydrogen atoms from a straight or branched alkane (i.e., the basic chain corresponding to the straight or branched alkyl).

The present invention is further described below by way of examples, but they are not intended to limit the present invention.

The main raw materials used are as follows:

Cardanol, Shanghai Wujing Chemical Technology Co., Ltd., industrial products

Zinc chloride, concentrated sulfuric acid, hydrogen peroxide (30%), formic acid, boric acid, diethanolamine, diethylenetriamine, ethanolamine, N-(2-hydroxyethyl)ethylenediamine, tert-butyl chloride, and hexadecanol were all purchased from Sinopharm Chemical Reagent Co., Ltd. and were of analytical grade.

Example 1 Preparation of tert-butylated epoxy cardanol

Take 100g of cardanol, 8g of formic acid, 0.3g of sulfuric acid, and 200g of hydrogen peroxide, add them to a three-necked flask with mechanical stirring, reflux condenser and temperature control, start stirring and heating. Maintain the reaction temperature at 70°C and react for 3 hours. After the reaction is completed, cool down to obtain a brown-red transparent liquid. Filter the reaction product and wash it with 5% KOH solution, then wash it with distilled water until neutral, and distill the organic phase under reduced pressure at 100Pa and 150°C for 1h to remove moisture and unreacted raw materials to obtain an orange-red transparent liquid epoxidized cardanol.

Dissolve 35g of epoxidized cardanol in 100ml of acetone, put it into a 250ml three-necked reaction flask after dissolving, add 0.9g of zinc chloride catalyst, start stirring and heating. Maintain the reaction temperature at 60°C, slowly drop 9.5g of tert-butyl chloride into the reaction flask, and continue the reaction for 3 hours after the addition is complete. After the reaction is completed, cool down to obtain a brown-red transparent liquid. Filter the reaction product and wash it with 5% KOH solution, then wash it with distilled water until it is neutral, and distill it under reduced pressure at 1000Pa and 120°C for 1h to remove the solvent, moisture and unreacted raw materials to obtain a brown-red viscous liquid tert-butylated epoxidized cardanol.

An exemplary reaction formula of the above reaction is shown below.

Example 2

22g of tert-butylated epoxy cardanol prepared in Example 1, 5g of N-(2-hydroxyethyl)ethylenediamine and 90g of toluene were added to a 250mL three-necked flask, heated under stirring, and reacted at 90°C for 3h. After the reaction was completed, the solvent and unreacted raw materials were removed by vacuum distillation for 1h to obtain dark brown viscous liquid tert-butylated amino cardanol, and then 3g of boric acid, 10g of N-(2-hydroxyethyl)ethylenediamine and 90g of cyclohexane were added to the reaction container, stirred, heated, dehydrated, reacted at 120°C for 3h, and finally filtered and evaporated to remove the solvent and unreacted N-(2-hydroxyethyl)ethylenediamine to obtain organic boron compound W-01.

An example reaction formula of the reaction is shown below, where R is H.

The product prepared in Example 2 was subjected to infrared spectroscopy analysis. The analysis results are shown in Table 1.

Table 1 Infrared analysis results of products

Table 1 shows that the product has characteristic peaks such as C-OH stretching vibration peak, C-NH stretching vibration peak, benzene ring skeleton stretching vibration peak, N-C stretching vibration peak, O-C stretching vibration peak and B-O stretching vibration peak, which can indicate that the synthesized product is the target compound.

Example 3

36g of tert-butylated epoxy cardanol prepared in Example 1, 10g of diethanolamine and 90g of toluene were added to a 250mL three-necked flask, heated under stirring, and reacted at 100°C for 4h. After the reaction was completed, the solvent and unreacted raw materials were removed by vacuum distillation for 1h to obtain a dark brown viscous liquid tert-butylated amino cardanol, and then 6g of boric acid, 20g of diethanolamine and 90g of cyclohexane were added to the reaction vessel, stirred, heated, dehydrated, reacted at 150°C for 4h, and finally filtered and evaporated to remove the solvent and unreacted diethanolamine to prepare the organic boron compound W-02.

Example 4

21.5g of tert-butylated epoxy cardanol prepared in Example 1, 6g of diethylenetriamine and 90g of toluene were added to a 250mL three-necked flask, heated under stirring, and reacted at 95°C for 2h. After the reaction was completed, the solvent and unreacted raw materials were removed by vacuum distillation for 1h to obtain a dark brown viscous liquid tert-butylated amino cardanol, and then 6g of boric acid, 8g of hexadecanol, 10.5g of diethylenetriamine and 90g of cyclohexane were added to the reaction vessel, stirred, heated, dehydrated, reacted at 145°C for 5h, and finally filtered and evaporated to remove the solvent and unreacted diethylenetriamine to prepare the organic boron compound W-03.

Comparative Example 1

36.3 g of hexadecanol, 18.3 g of ethanolamine, 6.2 g of boric acid and 90 g of toluene solvent were added into a reaction container, stirred, heated, and reacted at 145° C. for 6 hours. Finally, the solvent and unreacted ethanolamine were filtered and evaporated to obtain comparative organic boron compound V-01.

Examples 5-7 and Comparative Examples 2-3 of Air Compressor Lubricant Compositions

According to the formula composition in Table 2, Examples 5-7 and Comparative Examples 2-3 of the air compressor lubricant oil compositions were prepared, wherein the main additives and lubricant base oils used were from the following sources:

Antioxidant T501, Petrochemical Research Institute Xingpu Company, Industrial Products

Sulfur phosphoric acid nitrogen derivative T305, Shenyang Hualun Lubricant Additives Co., Ltd., industrial products

Copolymer of acrylic acid and ether T911, Shenyang Juxin Tiancheng Chemical Co., Ltd., Industrial products

Diisooctyl sebacate, Beijing Chemical Plant No. 3, industrial products

Table 2 Examples and Comparative Examples of Air Compressor Lubricant Compositions

The high temperature oxidation resistance and oxidation induction period of the air compressor lubricating oil compositions of the above-mentioned embodiments and comparative examples were evaluated respectively. The determination method was SH/T 0719, the testing instrument was a TA5000 DSC instrument of TA Company of the United States, and the testing conditions were: 190°C, oxygen pressure 0.5MPa, and heating rate 10°C/min.

The anti-wear performance of the air compressor lubricating oil compositions of the above-mentioned embodiments and comparative examples was measured respectively, the measuring method was the four-ball method SH/T 0189, the testing instrument was the K93190 four-ball testing machine produced by Koehler Company of the United States, and the testing conditions were 1200rpm, 75℃, 392N, 60min.

The evaluation results of high temperature oxidation resistance and wear resistance are shown in Table 3.

Table 3

sample Oxidation induction period/min Wear spot diameter/mm Example 5 19.8 0.52 Example 6 18.5 0.58 Example 7 17.6 0.63 Comparative Example 2 10.2 0.77 Comparative Example 3 14.7 0.70

Claims (10)

1. An air compressor lubricant composition, comprising, by mass percentage, 0.1% to 10% of an organic boron compound, 0.01% to 5% of an antioxidant, 0.01% to 5% of an extreme pressure anti-wear agent, 0.001% to 1% of a defoaming agent, and a major amount of an ester lubricating base oil, wherein the structure of the organic boron compound is as shown in formula (I):

In formula (I), there are a repeating unit L and b boron-containing groups, a is an integer between 1 and 10 (preferably an integer between 1 and 5), b is an integer between 1 and 5 (preferably an integer between 1 and 3), and a L groups are the same or different and are independently selected from the group represented by formula (II);

In formula (II), HO is bonded to the benzene ring (HO is preferably located at the meta position of the chain where R ₁ is located on the benzene ring); y R groups are bonded to the benzene ring; y is selected from an integer between 0 and 4 (preferably an integer between 1 and 3); the R groups are each independently selected from H and C _1-20 straight or branched alkyl (preferably each independently selected from H and C _1-4 straight or branched alkyl, more preferably tert-butyl); n is an integer between 1 and 10 (preferably an integer between 1 and 3); R ₁ is each independently selected from a single bond and a C _1-20 straight or branched alkylene (preferably selected from a single bond and a C _1-4 straight or branched alkylene); R ₂ in the n repeating units are the same or different from each other and are each independently selected from a single bond and a C _1-20 straight or branched alkylene (preferably each independently selected from a single bond and a C _1-4 straight or branched alkylene); R ₃ is selected from H and a C _1-20 straight or branched alkyl (preferably selected from H and C _1-4 straight or branched alkyl groups); the A groups in the n repeating units are the same or different from each other and are independently selected from a single bond,

The group represented by formula (III) and the group represented by formula (IV),

The _R4 groups are each independently selected from H and _C1-20 straight or branched alkyl (preferably selected from H and _C1-4 straight or branched alkyl); m is an integer between 0 and 10 (preferably an integer between 1 and 5); The R ₅ groups are each independently selected from a trivalent C _1-20 straight chain or branched chain alkyl group (preferably each independently selected from a trivalent C _1-4 straight chain or branched chain alkyl group); Each _G2 group is independently selected from the group bonded to the _G4 group present in the other L group other than the L group in which it is located, a _C1-10 straight or branched alkyl group, _-R6G3 , _and H; each _G3 group is independently selected from _-OG1 , a _C1-10 straight or branched alkyl group, and H (preferably, independently selected from _-OG1 , a _C1-4 straight or branched alkyl group, OH, and H); The R ₆ groups are selected from C _1-20 straight or branched alkylene groups (preferably each independently selected from C _1-4 straight or branched alkylene groups); The _G1 group is selected from the binding end bonded to the boron-containing group, H; The _G4 group is selected from the binding end bonded to the _G2 group present in other L groups other than the L group in which it is located, H; Among a L groups, at least one A group is selected from the group represented by formula (III), and at least one _G1 group is selected from the binding end bonded to the boron element in the boron-containing group; Each A' group in the b boron-containing groups is independently selected from the binding end bonded to the _G1 group present in the L group, the group represented by formula (V), -OR', and the R' group is H or a C _1-20 straight or branched alkyl group (preferably H or a C _1-4 straight or branched alkyl group);

In formula (V), m is an integer between 0 and 10 (preferably an integer between 1 and 5); The R ₀ groups are each independently selected from C _1-10 straight or branched alkyl, -R ₆ G ₅ , H (preferably each independently selected from C _1-4 straight or branched alkyl, -R ₆ G ₅ , H); The R ₅ groups are each independently selected from a trivalent C _1-20 straight chain or branched chain alkyl group (preferably each independently selected from a trivalent C _1-4 straight chain or branched chain alkyl group); The _G6 group is selected from _{-R6G5 , C1-4} straight or branched alkyl, H; The R ₆ groups are selected from C _1-20 straight or branched alkylene groups (preferably each independently selected from C _1-4 straight or branched alkylene groups); Each G ₅ group is independently selected from -OG ₁ , C _1-4 straight or branched alkyl, OH, H, wherein the G ₁ group is selected from the binding end bonded to the boron element in the boron-containing group, C _1-4 straight or branched alkyl, H; In the group represented by formula (V), there is at least one _G1 group selected from the binding end bonded to the boron element in the boron-containing group; Among the b said boron-containing groups, at least one A' group is selected from the binding end bonded to the _G1 group present in the L group; Each group in the organic boron compound complies with the bonding rules. 2. The lubricating oil composition according to claim 1, characterized in that the organic boron compound comprises one or more of the following structural compounds:

The R group is H or a C ₁ -C ₂₀ straight or branched chain alkyl group. 3. The lubricating oil composition according to claim 1, characterized in that the preparation method of the organic boron compound comprises the following steps: (1) reacting a compound represented by formula (X) with a peroxide;

In formula (X), HO is bonded to the benzene ring (HO is preferably located at the meta position of the chain where R ₁ is located on the benzene ring); y R groups are bonded to the benzene ring; y is selected from an integer between 0 and 4 (preferably an integer between 1 and 3); the R groups are each independently selected from H and C _1-20 straight or branched alkyl (preferably each independently selected from H and C _1-4 straight or branched alkyl, more preferably selected from tert-butyl); n is an integer between 1 and 10 (preferably an integer between 1 and 3); R ₁ is each independently selected from a single bond and a C _1-20 straight or branched alkylene (preferably selected from a single bond and a C _1-4 straight or branched alkylene); R ₂ in the n repeating units are the same or different from each other and are each independently selected from a single bond and a C _1-20 straight or branched alkylene (preferably each independently selected from a single bond and a C _1-4 straight or branched alkylene); R ₃ is selected from H and C _1-20 straight or branched chain alkyl groups (preferably selected from H and C _1-4 straight or branched chain alkyl groups); A" in the n repeating units are the same or different from each other and are independently selected from single bonds,

wherein the _R4 groups are independently selected from H and _C1-20 straight chain or branched alkyl (preferably selected from H and _C1-4 straight chain or branched alkyl); in formula (X), at least one A" is

(2) reacting the reaction product of step (1) with a compound represented by formula (Y);

In formula (Y), m is an integer between 0 and 10 (preferably an integer between 1 and 5); The R ₀ 'groups are each independently selected from C _1-10 straight or branched alkyl, -R ₆ OH, H (preferably each independently selected from C _1-4 straight or branched alkyl, -R ₆ OH, H); the R ₅ groups are each independently selected from trivalent C _1-20 straight or branched alkyl (preferably each independently selected from trivalent C _1-4 straight or branched alkyl); each G ₅ 'group is each independently selected from C _1-4 straight or branched alkyl, OH, H; the G ₆ 'group is selected from C _1-10 straight or branched alkyl, -R ₆ OH, H; the R ₆ groups are each independently selected from C _1-20 straight or branched alkylene (preferably each independently selected from C _1-4 straight or branched alkylene); In formula (Y), there is at least one G ₅ 'group selected from OH or at least one G ₆ 'group or R ₀ 'group selected from -R ₆ OH, and at least one R ₀ 'group or G ₆ 'group is H; (3) reacting the reaction product of step (2) with an inorganic boron compound and collecting the product. 4. The lubricating oil composition according to claim 3, characterized in that In step (1), the compound represented by formula (X) is selected from cardanol and alkylated cardanol; and/or the peroxide is selected from one or more of hydrogen peroxide, performic acid, peracetic acid, persulfonic acid, m-chloroperbenzoic acid, tert-butyl hydroperoxide, tert-butyl peracetate, methyl ethyl ketone peroxide, dibenzoyl peroxide and cyclohexanone peroxide; And/or, in step (2), the compound represented by formula (Y) is selected from one or more of aliphatic amines, polyene polyamines, aliphatic amines substituted with one or more hydroxy groups, and polyene polyamines substituted with one or more hydroxy groups; And/or, in step (3), the inorganic boron compound is selected from one or more of boric acid, boric oxide and boric acid half ester. 5. The lubricating oil composition according to claim 3, characterized in that the equivalent ratio between the compound represented by formula (X), the peroxide, the compound represented by formula (Y), and the inorganic boron compound is 1:0.5-10:0.5-10:0.5-5 (preferably 1:2-3:2-3:1-2). 6. The lubricating oil composition according to claim 3, characterized in that the reaction temperature of step (1) is 0-100°C (preferably 20-80°C); the reaction temperature of step (2) is 50-150°C (preferably 60-100°C); and the reaction temperature of step (3) is 80-200°C (preferably 110-150°C). 7. The lubricating oil composition according to claim 3, characterized in that the reaction time of step (1) is 1 to 10 hours (preferably 3 to 5 hours); the reaction time of step (2) is 1 to 10 hours (preferably 2 to 4 hours); and the reaction time of step (3) is 1 to 10 hours (preferably 3 to 5 hours). 8. The lubricating oil composition according to any one of claims 1 to 7, characterized in that the antioxidant is selected from phenolic antioxidants; the extreme pressure anti-wear agent is selected from one or more of sulfuric acid nitrogen derivatives, phosphates, phosphites, thiophosphate amine salts, sulfided olefins and dialkyl dithiocarbamates; the defoaming agent is selected from one or more of copolymers of acrylic acid and ether, methyl silicone oil and ethyl silicone oil; the ester lubricating base oil is a diester lubricating base oil. 9. The lubricating oil composition according to any one of claims 1 to 7, characterized in that the air compressor lubricating oil composition comprises, by mass percentage, 0.2% to 5% of an organic boron compound, 0.01% to 3% of an antioxidant, 0.01% to 3% of an extreme pressure anti-wear agent, 0.001% to 0.5% of a defoaming agent and a major amount of an ester lubricating base oil. 10. The method for preparing the air compressor lubricant oil composition according to any one of claims 1 to 9, comprising the step of mixing the additive in the air compressor lubricant oil composition with a lubricating base oil.