CN114478289A - Ester compound, preparation method and application thereof, and antioxidant composition - Google Patents

Abstract

在式(I)中，至少存在一个A基团选自式(II)所示的1价基团；

其中各基团的定义见说明书。本发明的酯类化合物具有优良的抗氧化、抗腐蚀性能，能够显著提高润滑油特别是酯基润滑油的高温抗腐蚀抗氧化性能、安定性。The invention provides an ester compound, a preparation method and application thereof. Ester compound of the present invention, its structure is shown in formula (I):

In formula (I), at least one A group is selected from the monovalent group represented by formula (II);

The definition of each group is shown in the specification. The ester compound of the present invention has excellent anti-oxidation and anti-corrosion properties, and can significantly improve the high-temperature anti-corrosion, anti-oxidation properties and stability of lubricating oil, especially ester-based lubricating oil.

Description

Ester compound and its preparation method, use and antioxidant composition

technical field

The present invention relates to an ester compound, in particular to an ester compound which can be used in aviation synthetic ester lubricating oil and has high temperature anti-oxidation and anti-corrosion properties.

Background technique

The high-temperature corrosion and oxidation stability of aero-engine lubricating oil is an important manifestation of the high-temperature oxidation resistance of aero-engine oil. Under the induction of high temperature oxygen and metal catalysis for a long time, the lubricating oil undergoes a series of chemical changes, resulting in a large number of deposits such as sludge, which seriously affects the normal operation of the aero-engine. It is of great significance to improve the high temperature corrosion and oxidation stability of aero-engine oil to improve the working efficiency and service life of lubricating system equipment.

With the development of the aviation industry and the increase of the flight speed of the aircraft, the main body temperature of the turbojet engine lubricating oil has increased from 80 ℃ in the early stage to the current 220 ℃. When the outlet temperature of the aero-engine oil is above 200 ℃, the oxidation of ordinary engine lubricating oil Velocities are multiplied, resulting in increased lubricant viscosity, increased total acid number, high corrosiveness, and large deposits. In order to effectively alleviate these problems, it is necessary to improve the high-temperature corrosion and oxidation stability of aero-engine lubricants.

The high-temperature corrosion and oxidation stability of aero-engine oils are closely related to the structure and high-temperature properties of base oils and antioxidants. Therefore, to effectively improve the high-temperature corrosion and oxidation stability of aero-engine oil, it is necessary to synthesize a high-temperature antioxidant and anti-corrosion agent with excellent chemical structure and high-temperature antioxidant properties, which can effectively alleviate the deterioration and deposition of aero-engine lubricating oil under high temperature conditions.

In the internationally renowned aviation lubricant specification MIL-PRF-7808L, the 100 ℃ kinematic viscosity grade of four centistokes (4mm ² /s) aero-engine lubricants requires both good high temperature oxidation resistance and low temperature flow. Therefore, it can ensure the fast flight of the aircraft under high temperature, high speed and high load, and ensure that the aircraft can take off quickly, maneuver flexibly, cruise at high speed and land safely in alpine regions. It is necessary to synthesize a high-temperature antioxidant with excellent chemical structure and high-temperature antioxidant properties, which can effectively protect the base oil, reduce the generation of oxidation products, reduce deposits, and effectively alleviate the problem of high-temperature oil deterioration and deposition of aero-engine oil, so as to ensure aero-engine oil. High temperature safe and stable work. At the same time, it keeps the lubricating oil composition with smaller kinematic viscosity at low temperature and better low temperature fluidity, which meets the requirements of MIL-PRF-7808L specification for kinematic viscosity at -51℃≤20000 (mm ² /s), and more It is beneficial to the low temperature lubrication service of lubricating oil, and it is beneficial to the safe and quick start of the flight of the aircraft in the low temperature environment.

SUMMARY OF THE INVENTION

The present invention provides an ester compound and its preparation method and application, including the following aspects.

In a first aspect, the present invention provides an ester compound.

Ester compound of the present invention, its structure is shown in formula (I):

In formula (I), n is an integer between 1 and 10, preferably an integer between 1 and 5, more preferably an integer between 1 and 3; R ₀ is selected from n-valent C _1-30 straight chain or Branched alkyl, C _2-30 linear or branched heteroalkyl, preferably selected from n-valent C _1-20 linear or branched alkyl, C _2-20 linear or branched heteroalkyl, more It is preferably selected from n-valent C _1-10 linear or branched chain alkyl, C _2-10 linear or branched heteroalkyl; each R' group is independently selected from C _1-10 linear or branched chain Alkylene, preferably selected from C _1-5 linear or branched alkylene, more preferably selected from C _1-3 linear or branched alkylene; each R" group is independently selected from C _{1- 30} straight-chain or branched-chain alkyl groups, preferably selected from C _1-20 straight-chain or branched-chain alkyl groups, more preferably C _1-10 straight-chain or branched-chain alkyl groups; each R"' group is independently selected From C _1-30 straight-chain or branched alkyl, preferably from C _1-20 straight or branched alkyl, more preferably from C _1-10 straight or branched alkyl; each A group is selected from The group represented by formula (II), H, C _1-20 linear or branched alkyl, preferably selected from the group represented by formula (II), H, C _1-10 linear or branched alkyl , more preferably selected from the group represented by formula (II), H, C _1-5 linear or branched alkyl, and at least one A group in formula (I) is selected from the group represented by formula (II) A monovalent group, the monovalent group represented by the formula (II) is bonded to the formula (I) through the R ₀ ' group, and the R ₀ ' group is selected from C _1-6 straight or branched chain alkylene;

Formula (II) is a monovalent group formed by the bonding of m structural units represented by formula (III) through R ₀ ' groups, wherein the R ₀ ' groups present are independently selected from C _{1～ 6} linear or branched alkylene, preferably selected from C _1-4 linear or branched alkylene, more preferably selected from C _1-3 linear or branched alkylene;

In formula (II), m is an integer between 1 and 10, preferably an integer between 1 and 5, more preferably an integer between 1 and 3; each R _I group is independently selected from H, C _{1 ~10} linear or branched alkyl, preferably selected from H, C _1-5 linear or branched alkyl, more preferably selected from H, C _1-3 linear or branched alkyl; each x is independently is selected from an integer between 0 and 4, preferably an integer between 0 and 2, more preferably 0 or 1; each R _II group is independently selected from H, C _1-10 straight or branched chain alkyl, preferably is selected from H, C _1-5 linear or branched chain alkyl, more preferably selected from H, C _1-3 linear or branched alkyl; each y is independently selected from an integer between 0 and 4, preferably An integer between 0 and 2, more preferably 0 or 1; each R _III group is independently selected from H, C _1-10 linear or branched alkyl, preferably H, C _1-5 linear or Branched alkyl, more preferably selected from H, C _1-3 straight or branched alkyl; each z is independently selected from an integer between 0 and 4, preferably an integer between 0 and 2, more preferably 0 or 1;

Each of L _I , L _II , and L _III in formula (II) is each independently H, C _1-10 alkyl, and is bonded to L _I , L _II or L _III in different structural units through a R ₀ ' group The binding end, the binding end bound to the formula (I) through the R ₀ ' group, the monovalent group represented by the formula (IV) (preferably H, C _1-4 alkyl, and different structural units) L _I , L _II or L _III are bonded through the R ₀ ' group, the bonding end is bonded to the formula (I) through the R ₀ ' group, the monovalent group represented by the formula (IV)); Each R ₀ ' group present therein is independently selected from C _1-6 straight-chain or branched alkylene, preferably from C _1-4 straight or branched alkylene, more preferably from C _{1- 3} straight or branched chain alkylene;

In formula (II), only one L _I , L _II or L _III is bonded to formula (I) through a R ₀ ' group, and one end of the R ₀ ' group is bonded to the naphthalene ring in the structural unit where it is located combined, the other end is bonded with formula (I);

* in the monovalent group represented by the formula (IV) represents a binding end bonded to L _I , L _II or L _III ;

In formula (IV), n is an integer between 1 and 10, preferably an integer between 1 and 5, more preferably an integer between 1 and 3; R ₀ is selected from n-valent C _1-30 straight chain or Branched alkyl, C _2-30 linear or branched heteroalkyl, preferably selected from n-valent C _1-20 linear or branched alkyl, C _2-20 linear or branched heteroalkyl, more It is preferably selected from n-valent C _1-10 linear or branched alkyl, C _2-10 linear or branched heteroalkyl; each R ₀ ' group is independently selected from C _1-6 linear or branched Chain alkylene, preferably selected from C _1-4 linear or branched alkylene, more preferably selected from C _1-3 linear or branched alkylene; each R' group is independently selected from C _{1 ~10} linear or branched alkylene, preferably selected from C _1-5 linear or branched alkylene, more preferably selected from C _1-3 linear or branched alkylene; each R" group is independently Independently selected from C _1-30 straight-chain or branched alkyl, preferably from C _1-20 straight or branched alkyl, more preferably from C _1-10 straight or branched alkyl; each R" The ' groups are each independently selected from C _1-30 straight-chain or branched-chain alkyl groups, preferably from C _1-20 straight-chain or branched-chain alkyl groups, more preferably from C _1-10 straight-chain or branched-chain alkyl groups .

According to the present invention, preferably, in formula (II), L _I , L _II and L _III in the same structural unit are not bonded to each other through R ₀ ' groups.

According to the present invention, in formula (II), when m=1, one of L _I , L _II , and L _III is the binding end bonded to formula (I) through the R ₀ ' group, and the other two are each is independently H, a C _1-4 alkyl group or a monovalent group represented by formula (IV), one end of the R ₀ ' group is bonded to the naphthalene ring in the structural unit where it is located, and the other end is bound to the naphthalene ring of the formula (I )Bond.

According to the present invention, in formula (II), when m=2, there are two structural units as shown in formula (III), L _I , L _II and L _III in different structural units (when they are all the same as When L _I , L _II or L _III in different structural units are bonded to each other through the R ₀ ' group, they can be bonded to each other through the R ₀ ' group. Each of L _I , L _II or L _III is bonded to each other via a R ₀ ' group, that is, the two structural units are bonded to each other via only one R ₀ ' group.

According to the present invention, in formula (II), when m is greater than 2, there are m structural units as shown in formula (III), L _I , L _II , L _III (when they are all of the m structural units) When L _I , L _II or L _III in different structural units are bonded to each other through the R ₀ ' group, they can be bonded to each other through the R ₀ ' group, and further optionally, the m structural units are One end structural unit, (m-2) intermediate structural units and another one end structural unit are sequentially bonded through the R ₀ ' group, and there is only one L in each end structural unit _I , L _II or L _III and L _I , L _II or L _III in the adjacent intermediate structural unit are bonded through R ₀ ' group, and there are 2 L _I , L in each intermediate structural unit _II or L _III are respectively bonded to L _I , L _II or L _III in the adjacent structural units through R ₀ ' groups, that is, only one R ₀ ' group is used between every two connected different structural units group bonding.

According to the present invention, examples of the group represented by formula (II) include:

wherein * represents the binding end bonded to the formula (I) through the R ₀ ' group.

According to the present invention, examples of the ester compound include:

In the molecular structural formulas of the ester compounds P-1, P-2, and P-3, the group AN represents the (II) group, and the specific molecular structure of the (II) group is shown above. Taking (II-1) as an example, the molecular structural formula of the ester compound formed by it is as follows:

The ester compound of the present invention has excellent anti-oxidation and anti-corrosion properties, can significantly improve the high-temperature anti-corrosion, anti-oxidative stability of lubricating oil, especially ester-based lubricating oil, and can significantly improve the aromatic amine anti-oxidant additive in the ester base. Solubility and stability in oil, significantly improve the solubility and dispersibility of consumed additive residues in base oil, reduce the formation of deposits of ester oils in high temperature environments, and enable ester lubricating oils Maintain good low temperature fluidity and low temperature viscosity.

In a second aspect, the present invention provides an antioxidant composition.

The antioxidant composition of the present invention comprises the ester compound described in any one of the preceding aspects and the compound represented by formula (II');

Formula (II') is a compound in which m structural units represented by formula (III') are bonded to each other through R ₀ ' groups,

In formula (II'), m is an integer between 1 and 10, preferably an integer between 1 and 5, more preferably an integer between 1 and 3; each R _I group is independently selected from H, C _1-10 straight-chain or branched-chain alkyl groups, preferably selected from H, C _1-5 straight-chain or branched-chain alkyl groups, more preferably selected from H, C _1-3 straight-chain or branched-chain alkyl groups; each x is independently is independently selected from an integer between 0 and 4, preferably an integer between 0 and 2, more preferably 0 or 1; each R _II group is independently selected from H, C _1-10 straight or branched chain alkyl, It is preferably selected from H, C _1-5 linear or branched chain alkyl, more preferably selected from H, C _1-3 linear or branched alkyl; each y is independently selected from an integer between 0 and 4, An integer between 0 and 2 is preferred, and 0 or 1 is more preferred; each R _III group is independently selected from H, C _1-10 linear or branched alkyl, preferably H, C _1-5 linear or branched alkyl, more preferably selected from H, C _1-3 straight or branched alkyl; each z is independently selected from an integer between 0 and 4, preferably an integer between 0 and 2, more preferably 0 or 1;

Each of L _I ', L _II ', and L _III ' in the formula (II') is independently H, C _1-4 alkyl, and passes through L _I ', L _II ', and L _III ' in different structural units. The binding end to which the R ₀ ' group is bonded.

According to the present invention, preferably, in formula (II'), L _I ', L _II ', and L _III ' in the same structural unit are not bonded to each other through R ₀ ' groups.

According to the present invention, in formula (II'), when m=1, L _I ', L _II ', and L _III ' are each independently H or C _1-4 alkyl.

According to the present invention, in formula (II'), when m=2, there are two structural units as shown in formula (III'), L _I ', L _II ', L _III ' ( When they are both binding ends bonded to L _I ', L _II ', and L _III ' in different structural units through the R ₀ ' group), they can bond with each other, preferably, between two structural units Only one L _I ', L _II ' or L _III ' in each case is bonded to each other via a R ₀ ' group, ie only one R ₀ ' group is bonded between 2 different structural units.

According to the present invention, in formula (II'), when m is greater than 2, there are m structural units as shown in formula (III'), and L _I ', L _II ', L _III ' ( When they are all binding ends bonded to L _I ', L _II ', and L _III ' in different structural units through the R ₀ ' group) they can be bonded to each other through the R ₀ ' group, further optional Ground, m structural units are 1 end structural unit, (m-2) middle structural unit and another 1 end structural unit bonded sequentially through the R ₀ ' group, and the structural unit of each end There is only one L _I ', L _II ' or L _III ' in the structural unit and the L _I ', L _II ' or L _III ' in the adjacent intermediate structural unit are bonded through the R ₀ ' group, and the middle There are 2 L _I ', L _II ' or L _III ' in each structural unit of , which are respectively bonded to L _I ', L _II ' or L _III ' in the adjacent structural unit through the R ₀ ' group , that is, only one R ₀ ' group is bonded between every two connected different structural units.

According to the present invention, examples of the compound represented by formula (II') include:

According to the present invention, preferably, the mass ratio between the ester compound described in any one of the preceding aspects and the compound represented by formula (II') is 1:0.1-5, more preferably 1:0.3-3.

The antioxidant composition of the present invention can well improve the oxidation stability, high temperature corrosion resistance, low temperature viscosity and low temperature fluidity of lubricating oil (especially synthetic lubricating oil), and is especially suitable for aviation synthetic lubricating oil (especially suitable for Four centistoke aviation lubricating oil), can effectively protect the base oil, reduce the generation of oxidation products, reduce deposits, effectively alleviate the high temperature oil deterioration and deposition problems of aircraft engine oil.

In the third aspect, the present invention proposes the use of the ester compound and the antioxidant composition described in any one of the preceding aspects.

The ester compounds described in any of the preceding aspects can be used as high-temperature antioxidants, which can significantly improve the high-temperature anti-corrosion, anti-oxidative stability of lubricating oils, especially ester-based lubricating oils, and at the same time significantly improve the dissolution of additives in ester-based base oils. It can significantly improve the solubility and dispersion performance of the consumed additive residues in the base oil, significantly reduce the formation of deposits of ester oils in high temperature environments, and can keep ester lubricants better low temperature fluidity and low temperature viscosity.

The antioxidant composition described in any one of the preceding aspects can be used as a high-temperature antioxidant and a free radical scavenger, and can significantly improve the high-temperature oxidation resistance and thermal degradation resistance of lubricating oils, especially ester base oils, and significantly reduce lubricating oils. The change rate of kinematic viscosity before and after oxidation, the change of total acid value, the formation of deposits, the quality change of metal test pieces before and after oxidation, prolong the use time of ester oil and reduce the frequency of oil change.

In a fourth aspect, the present invention provides a lubricating oil composition.

The lubricating oil composition of the present invention includes a lubricating base oil, the ester compound or the antioxidant composition described in any one of the preceding aspects. The ester compound or antioxidant composition described in any one of the preceding aspects accounts for 0.5% to 10% of the total mass of the lubricating oil composition, preferably 1.5% to 8% of the total mass of the lubricating oil composition. The lubricating base oils are preferably synthetic hydrocarbons and/or synthetic esters. The lubricating oil composition of the present invention may also add other kinds of additives, such as viscosity index improvers, antiwear agents, pour point depressants, rust inhibitors and the like.

The lubricating oil composition of the present invention has excellent oxidation stability and high temperature corrosion resistance. The preferred lubricating oil composition of the present invention maintains excellent low-temperature viscosity and low-temperature fluidity at -51°C, and can ensure safe and stable operation of the aero-engine at high temperature and safe and rapid start at low temperature.

In a fifth aspect, the present invention provides a method for preparing an ester compound.

The preparation method of the ester compound of the present invention comprises the step of reacting the compound represented by the formula (X), the compound represented by the formula (Y), the compound represented by the formula (Z) and/or a multimer thereof;

In formula (X), n is an integer between 1 and 10, preferably an integer between 1 and 5, more preferably an integer between 1 and 3; R ₀ is selected from n-valent C _1-30 straight chain or Branched alkyl, C _2-30 linear or branched heteroalkyl, preferably selected from n-valent C _1-20 linear or branched alkyl, C _2-20 linear or branched heteroalkyl, more It is preferably selected from n-valent C _1-10 linear or branched chain alkyl, C _2-10 linear or branched heteroalkyl; each R' group is independently selected from C _1-10 linear or branched chain Alkylene, preferably selected from C _1-5 linear or branched alkylene, more preferably selected from C _1-3 linear or branched alkylene; each R" group is independently selected from C _{1- 30} straight-chain or branched-chain alkyl groups, preferably selected from C _1-20 straight-chain or branched-chain alkyl groups, more preferably C _1-10 straight-chain or branched-chain alkyl groups; each R"' group is independently selected From C _1-30 straight-chain or branched alkyl, preferably from C _1-20 straight or branched alkyl, more preferably from C _1-10 straight or branched alkyl;

In formula (Y), each R _I group is independently selected from H, C _1-10 linear or branched alkyl, preferably H, C _1-5 linear or branched alkyl, more preferably selected from H, C _1-3 straight or branched chain alkyl; each x is independently selected from an integer between 0 and 4, preferably an integer between 0 and 2, more preferably 0 or 1; each R _II group Each group is independently selected from H, C _1-10 linear or branched chain alkyl, preferably selected from H, C _1-5 linear or branched alkyl, more preferably selected from H, C _1-3 linear or branched chain alkyl; each y is independently selected from an integer between 0 and 4, preferably an integer between 0 and 2, more preferably 0 or 1; each R _III group is independently selected from H, C _{1~ 10} Linear or branched alkyl, preferably selected from H, C _1-5 linear or branched alkyl, more preferably selected from H, C _1-3 linear or branched alkyl; each z is independently selected An integer from 0 to 4, preferably an integer from 0 to 2, more preferably 0 or 1;

In formula (Z), R ₀ " groups are each independently selected from H, C _1-5 straight-chain or branched alkylene, preferably H, C _1-3 straight or branched alkylene, More preferably selected from H and C _1-2 alkylene.

According to the preparation method of the present invention, the compound represented by the formula (X) is preferably selected from the esterification products of C _1-18 monohydric alcohols and/or polyhydric alcohols and C _3-20 fatty acids, the C _1-18 polyhydric alcohols Including one or more of ethylene glycol, trimethylolpropane, pentaerythritol, dipentaerythritol and tripentaerythritol, and the fatty acids of C _3-20 include valeric acid, isovaleric acid, caproic acid, heptanoic acid, caprylic acid, One or more of isooctanoic acid, 2-ethylhexanoic acid, nonanoic acid, 3,5,5-trimethylhexanoic acid, capric acid, lauric acid, palmitic acid and oleic acid. The compound represented by the formula (X) is more preferably the esterification product of one or more of trimethylolpropane, pentaerythritol, and dipentaerythritol with saturated fatty acids of C _3-20 , and further preferably the kinematic viscosity at 100°C is (3.6 -4.2) mm ² /s of one or more of trimethylolpropane ester, pentaerythritol ester and dipentaerythritol ester.

According to the preparation method of the present invention, examples of the compound represented by the formula (X) include one or more of the following structural compounds:

According to the preparation method of the present invention, the mass ratio between the compound represented by the formula (X) and the compound represented by the formula (Y) is preferably 1:0.1-5, more preferably 1:0.3-3;

According to the preparation method of the present invention, the molar ratio between the compound represented by the formula (Y), the compound represented by the formula (Z) and/or its multimer is preferably 1:0.3-2.0, more preferably 1:0.75-1.5 ; The temperature at which the compound represented by the formula (X), the compound represented by the formula (Y), the compound represented by the formula (Z) and/or its multimers react is preferably 60 to 120°C, more preferably 70 to 110°C; The absolute pressure under which the compound represented by the formula (X), the compound represented by the formula (Y), the compound represented by the formula (Z) and/or its polymer react is not particularly limited, and is generally preferably 0.01MPa to 0.12MPa, More preferably, it is 0.01 MPa to 0.10 MPa.

According to the preparation method of the present invention, the time for the reaction of the compound represented by the formula (X), the compound represented by the formula (Y), the compound represented by the formula (Z) and/or its multimer is suitable for the reaction to proceed smoothly, Usually, the longer the better, generally preferably 1 to 10 hours, more preferably 2 to 6 hours.

According to the preparation method of the present invention, preferably, in the compound represented by formula (Y), the 4 and 6 positions of the naphthalene ring to which the amine group is connected are hydrogen atoms.

According to the preparation method of the present invention, preferably, the compound represented by the formula (X) can be selected from one or more of the following compounds: trimethylolpropane saturated acid ester, pentaerythritol saturated acid ester, dipentaerythritol saturated acid ester , Isooctyl di-n-decanoate.

According to the preparation method of the present invention, preferably, the compound represented by formula (Y) can be selected from one or more of the following compounds: N-(p-tert-butylphenyl)-1-naphthylamine, N- (p-tert-octylphenyl)-1-naphthylamine, N-(p-phenethylphenyl)-1-naphthylamine, N-phenyl-1-naphthylamine.

According to the preparation method of the present invention, preferably, the compound represented by formula (Z) can be selected from one or more of the following compounds: one or more of formaldehyde, paraformaldehyde, acetaldehyde, benzaldehyde and parabenzaldehyde one or more.

According to the preparation method of the present invention, a catalyst may or may not be added to the reaction of the compound represented by the formula (X), the compound represented by the formula (Y), the compound represented by the formula (Z) and/or a polymer thereof , preferably adding a catalyst. The catalyst is preferably an acidic catalyst. _{The acidic catalyst can be one or more of glacial acetic acid, acetic acid, sulfuric acid, hydrochloric acid, phosphoric acid, SO and P 2 O 5 or an} aqueous solution of these substances and mixtures thereof, preferably sulfuric acid and/or glacial acetic acid or their mixtures. Aqueous solution, most preferably glacial acetic acid or acetic acid solution with a mass percentage of 60% to 100%. The added amount of the catalyst is preferably 3% to 20% of the mass of the compound represented by the formula (X). The catalyst can be removed by distillation under reduced pressure, alkali washing and water washing.

According to the preparation method of the present invention, the reaction of the compound represented by the formula (X), the compound represented by the formula (Y), the compound represented by the formula (Z) and/or the polymer thereof is preferably carried out under the protection of an inert gas. The gas is preferably nitrogen.

According to the preparation method of the present invention, a solvent may or may not be added to the reaction of the compound represented by the formula (X), the compound represented by the formula (Y), the compound represented by the formula (Z) and/or a polymer thereof . The solvent is preferably C ₆ -C ₂₀ alkane, most preferably C ₆ -C ₁₀ alkane, such as n-decane, n-heptane, cyclohexane. The solvent can be removed by conventional methods such as distillation or extraction, and is not particularly limited.

According to the preparation method of the present invention, the reaction product of the compound represented by formula (X), the compound represented by formula (Y), the compound represented by formula (Z) and/or its multimer can be a single ester compound, It can also be a mixture of multiple ester compounds, can also be a mixture of one or more ester compounds and the compound represented by the formula (II') described in the second aspect, and can also be one or more esters A mixture of the compound, the compound represented by the formula (II') and the compound represented by the formula (X) in the second aspect.

According to the preparation method of the present invention, the reaction product of the compound represented by formula (X), the compound represented by formula (Y), the compound represented by formula (Z) and/or its multimer can be a single ester compound, It can also be a mixture composed of multiple ester compounds, these reaction products are all expected by the present invention, and the difference in their existing forms does not affect the realization of the effects of the present invention. Therefore, in the context of this specification, these reaction products are collectively referred to as the ester 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 isolate an ester compound of a specific structure from the reaction product. Of course, this purification or separation is preferred for further improvement of the intended effect of the present invention, but is not necessary for the present invention. However, as the purification or separation method, for example, the reaction product can be purified and separated by a method such as column chromatography or preparative chromatography.

According to the preparation method of the present invention, the reaction product of the compound represented by the formula (X), the compound represented by the formula (Y), the compound represented by the formula (Z) and/or its multimer can be one or more ester compounds The mixture with the compound represented by the formula (II') described in the second aspect, the mixture is the antioxidant composition described in the second aspect of the present invention. In addition to reacting with the compound represented by the formula (X), the compound represented by the formula (Y) can also undergo a coupling reaction between its own molecules in the reaction process, and the coupling product between its own molecules is the formula (II') Compounds in which m is greater than 1 are shown. Therefore, the compound represented by the formula (II') includes the unreacted compound represented by the formula (Y) (that is, the compound represented by the formula (II') in which m is equal to 1) and the compound represented by the formula (Y) Coupling product between self-molecules (that is, the compound in which m is greater than 1 in the compound represented by the formula (II')).

According to the preparation method of the present invention, when the reaction product of the compound represented by the formula (X), the compound represented by the formula (Y), the compound represented by the formula (Z) and/or its multimer is one or more ester compounds When it is mixed with the compound represented by the formula (II') described in the second aspect, the compound represented by the formula (II') described in the second aspect may be separated; The compound represented by the formula (II') is isolated and used directly as the antioxidant composition of the present invention.

According to the preparation method of the present invention, the reaction product of the compound represented by the formula (X), the compound represented by the formula (Y), the compound represented by the formula (Z) and/or its multimer can be one or more ester compounds A mixture with the compound represented by the formula (II') and the compound represented by the formula (X) in the second aspect. The reaction product may contain the compound represented by the formula (X), that is, the unreacted compound represented by the formula (X).

According to the preparation method of the present invention, when the reaction product of the compound represented by the formula (X), the compound represented by the formula (Y), the compound represented by the formula (Z) and/or its multimer is one or more ester compounds When it is mixed with the compound represented by the formula (II') and the compound represented by the formula (X) described in the second aspect, the compound represented by the formula (X) can be separated; the compound represented by the formula (X) can also not be separated. is isolated and the compound of formula (X) is used as an additional component. Because the compound represented by the formula (X) itself is an ester compound, it can be used as a lubricating base oil or an antiwear agent, a friction modifier, and can be used as an additional component.

According to the preparation method of the present invention, unreacted formula (Z) may be present in the reaction product of the compound represented by formula (X), the compound represented by formula (Y), the compound represented by formula (Z) and/or its multimer The compound and/or its multipolymer, the unreacted compound represented by the formula (Z) and/or its multipolymer can be removed by conventional methods such as distillation or extraction, and are not particularly limited.

According to the preparation method of the present invention, the reaction product can be purified to improve the purity of the reaction product. Examples of the purification operation method include washing, recrystallization and the like, and are not particularly limited.

According to the preparation method of the present invention, in the reaction of the compound represented by the formula (X), the compound represented by the formula (Y), the compound represented by the formula (Z) and/or a polymer thereof, the reaction product can be purified. to improve the purity of the reaction product. Examples of the purification operation method include washing, recrystallization and the like, and are not particularly limited.

In a sixth aspect, the present invention also provides a method for improving the antioxidant and anticorrosion properties of a lubricating oil composition, the method comprising adding the ester antioxidant compound composition described in any one of the preceding aspects into a lubricating oil.

Description of drawings

Fig. 1 is the high performance liquid chromatography mass spectrogram of the physical mixing system of reaction raw material N-(P-tert-octylphenyl)-1-naphthylamine (L06) and ester.

Fig. 2 is the high performance liquid chromatography mass spectrogram of the synthetic product A1 (namely N-(P-tert-octylphenyl)-1-naphthylamine-ester-formaldehyde polycondensate).

Detailed ways

In the context of this specification, the expression "number + valence + group" or similar terms refers to removing the number represented by the number from the base structure (such as a chain, ring, or combination thereof, etc.) to which the group corresponds. The group obtained after the number of hydrogen atoms, preferably refers to the 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 group. For example, "3-valent linear or branched alkyl" refers to a linear or branched alkane (ie, the base chain to which the linear or branched alkyl group corresponds) by removing 3 hydrogen atoms group, and "2-valent straight-chain or branched heteroalkyl" refers to a straight or branched chain heteroalkane (preferably from the carbon atoms contained in the heteroalkane, or further, from a non-same carbon atom ) by removing 2 hydrogen atoms.

In the context of this specification, said heteroalkyl means that the carbon chain structure of an alkyl group is separated by one or more (such as 1 to 5, 1 to 4, 1 to 3, 1 to 2, or 1 ) is selected from -Sx-, -O- and -NR""- in the group obtained by interrupting the hetero group, wherein x is an integer between 1-5 (preferably an integer between 1-4, more 1, 2 or 3) are preferred. From the viewpoint of structural stability, preferably, when there are multiple hetero groups, any two of the hetero groups are not directly bonded. Obviously, the hetero group is not at the end of the carbon chain of the hydrocarbyl group. For the convenience of expression, the number of carbon atoms of the alkyl group before the interruption is still used to refer to the number of carbon atoms of the heteroalkyl group after the interruption. As a specific example, C ₄ linear alkyl (CH ₃ -CH ₂ -CH ₂ -CH ₂ -) is interrupted by a hetero group -O- to obtain CH ₃ -O-CH ₂ -CH ₂ -CH ₂ -, CH ₃ -CH ₂ -O-CH ₂ -CH ₂ - or CH ₃ -CH ₂ -CH ₂ -O-CH ₂ - etc. C ₄ straight chain heteroalkyl, interrupted by two hetero groups -S- Afterwards, _CH3 -S- _CH2 -S- _CH2 -CH2-, _CH3 - _CH2 -S- _CH2 -S-CH2- or _{CH3 -} S- _CH2 - _{CH2 -} S- CH ₂ - etc. C ₄ straight chain heteroalkyl, which can be interrupted by three hetero groups -S- to obtain CH ₃ -S-CH ₂ -S-CH ₂ -S-CH ₂ - etc. C ₄ straight chain heteroalkane base.

The percentages and ratios mentioned below are all mass percentages or mass ratios unless otherwise stated.

The main raw materials used are as follows:

Antioxidant L-06, p-tert-octylphenyl-1-naphthylamine, BASF-Ciba Fine Products Co., Ltd., chemically pure antioxidant PNA, n-phenyl-1-naphthylamine, Academy of Petrochemical Engineering Research Institute Xingpu Company, chemically pure

Antioxidant AO-150, American King's Chemical Co., Ltd., mixed alkyl diphenylamine

Rust inhibitor 5-methylbenzenetriazole, Shanghai Chemical Plant, chemically pure

VANLUBE9317, a mixture of p-tert-octylphenyl-1-naphthylamine, 4,4'-diisooctyl-diphenylamine and pentaerythritol esters, Vanderbilt, USA

VANLUBEV81, 4,4'-diisooctyl-diphenylamine, Vanderbilt, USA

VANLUBENA, a mixture of 4,4'-diisooctyl-diphenylamine and pentaerythritol esters, Vanderbilt, USA

Four centiStokes trimethylolpropane saturated fatty acid ester, 100 ℃ kinematic viscosity = 3.8mm ² /s, Shandong Ruijie Chemical Co., Ltd., >98%

Pentaerythritol ester, Zhejiang Quzhou Chemical Co., Ltd., 100℃ kinematic viscosity=5.02mm ² /s, >98%

Seven centistokes dipentaerythritol ester, Shandong Ruijie Chemical Co., Ltd., 100℃ kinematic viscosity=7mm ² /s, >98%

Trimethylolpropane oleate, Shandong Ruijie Chemical Co., Ltd., 100℃ kinematic viscosity=8.5mm ² /s, >97%

Five centistein trimethylolpropane ester, Sinopec Great Wall Lubricant Chongqing Branch, commodity code is Great Wall 5101 high temperature synthetic lubricating oil, 100 ℃ kinematic viscosity = 5.05mm ² /s, > 98%

Example 1

66.2g of N-(p-tert-octylphenyl)-1-naphthylamine was added to 72.2g of trimethylolpropane saturated fatty acid ester with 100°C kinematic viscosity=3.8mm ² /s, and added to the mixed system. 7.2g of paraformaldehyde was added; the mixed reaction system was heated, stirred and dissolved in a nitrogen atmosphere, maintained at 80°C, and 18g of reaction catalyst glacial acetic acid was added to the reaction system; the reaction was carried out at 100°C for 3 hours, and the mixing The reaction system is subjected to vacuum distillation for 60mins at 110°C and vacuum degree < 500Pa, and continues to carry out sufficient vacuum distillation for 30mins to 180mins at not higher than 160°C and vacuum degree < 500Pa to obtain 142g of reaction product A1; Compounds comprising structural formula P-1, structural formula P-2, structural formula P-3, and a smaller amount of compounds of structural formula II'-1, structural formula II'-2, structural formula II'-3, and a small amount of the three compounds in this example. Methylolpropane saturated fatty acid ester. The physical mixture system of reaction raw material N-(P-tert-octylphenyl)-1-naphthylamine (L06) and trimethylolpropane saturated fatty acid ester and reaction product A1 were analyzed by high performance liquid chromatography and mass spectrometry respectively.

Fig. 1 is the high performance liquid chromatography mass spectrogram of the physical mixing system of reaction raw material N-(P-tert-octylphenyl)-1-naphthylamine (L06) and ester.

Fig. 2 is the high performance liquid chromatography mass spectrogram of the synthetic product A1 (namely N-(P-tert-octylphenyl)-1-naphthylamine-ester-formaldehyde polycondensate).

Through comparative analysis, it can be seen that in the HPLC mass spectrum of the physical mixing system of the reaction raw materials in Figure 1, it can be seen that 330.9 is the mass-to-charge ratio peak of the reaction raw material N-(P-tert-octylphenyl)-1-naphthylamine ; 523.8 and 551.3 are the mass-to-charge ratio peaks of some polyol esters in the polyol ester solvent oil; in the HPLC mass spectrum of the reaction product A1 in Figure 2, it can be seen that 895 and 916 are ester-arylamine low The charge ratio peaks of the polymeric substances, 675/1019/1225, are the bimolecular polycondensates of aromatic amines, the trimolecular polycondensates of aromatic amines, and the polycondensation polymers of bimolecular polycondensates of aromatic amines and esters, respectively. In addition, there are more mass-to-charge ratio peaks of other polycondensation polymer molecules in Fig. 2, which well illustrates that the formaldehyde polycondensation reaction occurs between the reaction raw materials, resulting in the new polycondensation polymer composition of the present invention.

The mass-to-charge ratios of some synthesized aromatic amine formaldehyde polycondensate molecules are as follows:

(331.4+550.5+14-2+1)/1=895.6; (331.4+572.2+14-2+1)/1=916.2;

(331.4*2+14-2+1)/1=675.8; (331.4*3+28-4+1)/1=1019.2;

(331.4*2+523+28-4+1)/1=1225.2…

Example 2

99g of N-(p-tert-octylphenyl)-1-naphthylamine was added to 108g of mixed polyol saturated fatty acid esters (wherein trimethylolpropane ester 81g, dipentaerythritol ester 27g), in the mixed system 12g of paraformaldehyde was added; the mixed reaction system was heated, stirred, and dissolved in a nitrogen atmosphere, and the mixed system was maintained at about 90 °C, and 22 g of glacial acetic acid, a reaction catalyst, was added to the reaction system; the reaction was carried out at 90 °C for 4 hours, and the mixed reaction system was Under the condition of 110℃, vacuum degree <500Pa vacuum distillation for 60mins, continue to carry out sufficient vacuum distillation under 160℃, vacuum degree<500Pa for 30mins～180mins to obtain 210g reaction product A2; the reaction product A2 mainly contains and Compounds with similar structures of structural formula P-1, structural formula P-2, and structural formula P-3 (the difference is that the ester group is the ester group of the mixed polyol saturated fatty acid ester used in this example). At the same time, a smaller amount of compounds of structural formula II'-1, structural formula II'-2, structural formula II'-3, and a small amount of the mixed polyol saturated fatty acid ester in this example are included.

Example 3

The N-(p-tert-octyl phenyl)-1-naphthylamine of 132g is added to 156g four centistokes polyol saturated fatty acid ester (wherein trimethylolpropane ester 78g, pentaerythritol ester 78g, the two mass ratios are 1:1), add 30g of paraformaldehyde to the mixed system; under nitrogen environment, heat, stir and dissolve the mixed reaction system, maintain the mixed system at about 100°C, and start adding 30 g of reaction catalyst glacial acetic acid to the reaction system; At 100°C for 3h, the mixed reaction system was subjected to vacuum distillation at 110°C and vacuum degree <500Pa for 60mins, and continued to be fully vacuum distilled at not higher than 160°C and vacuum degree <500Pa for 30mins ~ 180mins to obtain 153.5g Reaction product A3; The reaction product A3 mainly contains compounds with similar structures as structural formula P-1, structural formula P-2, and structural formula P-3 (the difference is that the ester group therein is the polyol saturated fatty acid ester used in this example. ester group). At the same time, smaller amounts of compounds of structural formula II'-1, structural formula II'-2, structural formula II'-3 and a small amount of polyol saturated fatty acid ester in this example are included.

Example 4

132g of N-(p-tert-octylphenyl)-1-naphthylamine was added to 156g of seven centistos bis-pentaerythritol saturated fatty acid ester, and 30g of paraformaldehyde was added to the mixed system; Heating, stirring and dissolving, maintaining the mixed system at about 100 °C, began to add 30 g of reaction catalyst glacial acetic acid to the reaction system; the reaction was carried out at 100 °C for 3 hours, and the mixed reaction system was subjected to vacuum distillation at 110 °C, vacuum degree < 500Pa for 60mins , continue to carry out sufficient vacuum distillation for 30mins～180mins at not higher than 160°C and vacuum degree <500Pa to obtain 153.5g reaction product A4; the reaction product A4 mainly contains structural formula II'-1, structural formula II'-2, structural formula The compounds of II'-3, and a small amount of dipentaerythritol saturated fatty acid esters in this example, also contain compounds with similar structures to those of structural formula P-1, structural formula P-2, and structural formula P-3 (the difference is the ester group in them) is the ester group of dipentaerythritol saturated fatty acid ester). At the same time, smaller amounts of compounds of structural formula II'-1, structural formula II'-2, structural formula II'-3 and a small amount of dipentaerythritol saturated fatty acid ester in this example are included.

Example 5

132g of N-(p-tert-octylphenyl)-1-naphthylamine was added to 156g of seven centistokes trimethylolpropane oleate, and 30g of paraformaldehyde was added to the mixed system; The reaction system was heated, stirred and dissolved, and the mixed system was maintained at about 100 °C, and 30 g of the reaction catalyst glacial acetic acid was added to the reaction system; the reaction was carried out at 100 °C for 3 hours, and the mixed reaction system was decompressed at 110 °C with a vacuum degree of <500Pa Distillation for 60mins, continue to carry out sufficient vacuum distillation for 30mins～180mins under not higher than 160 ℃, vacuum degree <500Pa, to obtain 150g reaction product A5, the reaction product A5 mainly comprises structural formula II'-1, structural formula II'-2, The compounds of structural formula II'-3, and a small amount of trimethylolpropane oleate used in this example, also include compounds with structures similar to those of structural formula P-1, structural formula P-2, and structural formula P-3 (the difference is in which The ester group is the ester group of trimethylolpropane oleate). Also included are smaller amounts of compounds of formula II'-1, formula II'-2, and formula II'-3, as well as minor amounts of trimethylolpropane oleate in this example.

Contrast Antioxidants

The commonly used antioxidants V81, L-06, phenyl-1-naphthylamine T531, Thiazanthraquinone, Vanlube9317, and VanlubeNA were used as comparative antioxidants.

High temperature corrosion resistance and oxidation stability evaluation

The reaction product of the present invention, the comparative antioxidant and tricresol phosphate (TCP) were respectively added to the saturated fatty acid ester of four centistoke polyols, and added and stirred at 80° C. to prepare the embodiments 6-10 and 10 of the lubricating oil composition. Comparative Examples 1-6, wherein the mass percentage of tricresol phosphate is 1%. The formulation ratios of antioxidants in Examples 6-10 and Comparative Examples 1-6 of the lubricating oil compositions are shown in Table 1.

Table 1 Examples 6-10 and Comparative Examples 1-6 of lubricating oil compositions

All the lubricating oil compositions corresponding to Examples 6-10 and Comparative Examples 1-6 in Table 1 were measured for low temperature kinematic viscosity at -51°C, and all lubricating oil compositions in Table 1 were subjected to high temperature corrosion and oxidation stability Experiment, to evaluate the high temperature oxidation resistance and anti-deposition performance, the evaluation method used is ASTM D4636 corrosion and oxidation stability determination method specified in MIL-PRF-7808L specification for high temperature corrosion and oxidation stability evaluation of aviation lubricating oil, test conditions It is: the temperature is 220°C, the time is 40h, the air flow is 50mL/min, and the oil sample consumption is 100mL.

The evaluation indexes of this method are: change of total acid value before and after oxidation of oil sample (△TAN/mgKOH·g ^-1 ); change rate of viscosity at 40℃ (△Viscosity%); amount of sediment formation in 100 mL test oil sample (Deposit/mg·g -1 ) (100mL) ^-1 ); mass change per unit area of metallic copper, steel, silver, aluminum, titanium and other metal test pieces. In the present invention, the test results are illustrated by the quality change data of the copper sheet.

The above test results are shown in Tables 2 and 3.

Table 2 High temperature corrosion and oxidation stability evaluation test results

Comparing the MIL-PRF-7808L specification requirements with the results of the corrosion and oxidation stability evaluation data in Tables 2 and 3, it can be seen that the 4 cSt lubricating oil composition Examples 6-9 before and after oxidation with the reaction product of the present invention are added. Compared with the lubricating oil compositions of Comparative Examples 1-4, the quality of metal flakes, the total acid value, the viscosity change rate, and the amount of deposits formed have significant advantages, and its high-temperature oxidation resistance is significantly better than that of the single lubricating oil compositions in Comparative Examples 1-4. Aromatic amine antioxidants. The ester compound of the invention can better control the change of the total acid value of the oil product before and after the oxidation of the lubricating oil, the rate of change of viscosity and the amount of deposit formation, and well meets the requirements of the MIL-PRF-7808L index corrosion and oxidation stability index. The -51°C low temperature viscosity of the lubricating oil composition of Example 10 was greater than the standard value. The data of Example 9 shows that the ester compound synthesized by adopting the 7-centiStokes dipentaerythritol saturated ester base oil also has good high-temperature oxidation resistance and anti-sedimentation performance, but it is different from the 4-centistes polyol saturated organic acid ester. The compounded lubricating oil composition has a kinematic viscosity of ≥25000 (mm ² /s) at -51°C, which also does not meet the requirements of MIL-PRF-7808L for a kinematic viscosity of ≤20000 (mm ² /s) at -51°C.

The kinematic viscosity at -51°C of the compositions of Examples 6-8 is less than or equal to 19000 (mm ² /s) and meets the requirements of MIL-PRF-7808L, that is, the kinematic viscosity at -51°C is less than or equal to -20000 (mm ² /s); Comparative Examples 5-6 The kinematic viscosity at -51°C of the corresponding 4 centistoke lubricating oil composition is ≥21000 (mm ² /s), which does not meet the requirements of MIL-PRF-7808L and the kinematic viscosity at -51°C is less than or equal to 20000 (mm ² /s).

Table 3 High temperature corrosion and oxidation stability evaluation test results

The lubricating oil composition prepared by blending the ester compounds of the present invention exhibits better high-temperature oxidation resistance and anti-sedimentation performance, and its high-temperature oxidation resistance is obviously better than that of monomeric aromatic amine antioxidants. At the same time, the lubricating oil composition of 4 centistokes grade of the present invention has smaller kinematic viscosity at low temperature, better low temperature fluidity, and conforms to MIL-PRF-7808L specification at -51°C kinematic viscosity≤20000 (mm ² /s ) index requirements, which is more conducive to the low temperature lubrication service of lubricating oil, and is conducive to the rapid start of the engine at low temperature.

Claims (20)

1. Ester compound, its structure is shown in formula (I):

In formula (I), n is an integer between 1 and 10, preferably an integer between 1 and 5, more preferably an integer between 1 and 3; R ₀ is selected from n-valent C _1-30 straight chain or Branched alkyl, C _2-30 linear or branched heteroalkyl, preferably selected from n-valent C _1-20 linear or branched alkyl, C _2-20 linear or branched heteroalkyl, more It is preferably selected from n-valent C _1-10 linear or branched chain alkyl, C _2-10 linear or branched heteroalkyl; each R' group is independently selected from C _1-10 linear or branched chain Alkylene, preferably selected from C _1-5 linear or branched alkylene, more preferably selected from C _1-3 linear or branched alkylene; each R" group is independently selected from C _{1- 30} straight-chain or branched-chain alkyl groups, preferably selected from C _1-20 straight-chain or branched-chain alkyl groups, more preferably C _1-10 straight-chain or branched-chain alkyl groups; each R"' group is independently selected From C _1-30 straight-chain or branched alkyl, preferably from C _1-20 straight or branched alkyl, more preferably from C _1-10 straight or branched alkyl; each A group is selected from The group represented by formula (II), H, C _1-20 linear or branched alkyl, preferably selected from the group represented by formula (II), H, C _1-10 linear or branched alkyl , more preferably selected from the group represented by formula (II), H, C _1-5 linear or branched alkyl, and at least one A group in formula (I) is selected from the group represented by formula (II) A monovalent group, the monovalent group represented by the formula (II) is bonded to the formula (I) through the R ₀ ' group, and the R ₀ ' group is selected from C _1-6 straight or branched chain alkylene;

Formula (II) is a monovalent group formed by the bonding of m structural units represented by formula (III) through R ₀ ' groups, wherein the R ₀ ' groups present are independently selected from C _{1～ 6} linear or branched alkylene, preferably selected from C _1-4 linear or branched alkylene, more preferably selected from C _1-3 linear or branched alkylene;

In formula (II), m is an integer between 1 and 10, preferably an integer between 1 and 5, more preferably an integer between 1 and 3; each R _I group is independently selected from H, C _{1 ~10} linear or branched alkyl, preferably selected from H, C _1-5 linear or branched alkyl, more preferably selected from H, C _1-3 linear or branched alkyl; each x is independently is selected from an integer between 0 and 4, preferably an integer between 0 and 2, more preferably 0 or 1; each R _II group is independently selected from H, C _1-10 straight or branched chain alkyl, preferably is selected from H, C _1-5 linear or branched chain alkyl, more preferably selected from H, C _1-3 linear or branched alkyl; each y is independently selected from an integer between 0 and 4, preferably An integer between 0 and 2, more preferably 0 or 1; each R _III group is independently selected from H, C _1-10 linear or branched alkyl, preferably H, C _1-5 linear or Branched alkyl, more preferably selected from H, C _1-3 straight or branched alkyl; each z is independently selected from an integer between 0 and 4, preferably an integer between 0 and 2, more preferably 0 or 1; Each of L _I , L _II , and L _III in formula (II) is each independently H, C _1-10 alkyl, and is bonded to L _I , L _II or L _III in different structural units through a R ₀ ' group The binding end, the binding end bound to the formula (I) through the R ₀ ' group, the monovalent group represented by the formula (IV) (preferably H, C _1-4 alkyl, and different structural units) L _I , L _II or L _III is bonded to the terminal through the R ₀ ' group, the terminal is bonded to the formula (I) through the R ₀ ' group, the monovalent group represented by the formula (IV)); Each R ₀ ' group present therein is independently selected from C _1-6 straight-chain or branched alkylene, preferably from C _1-4 straight or branched alkylene, more preferably from C _{1- 3} straight or branched chain alkylene; In formula (II), only one L _I , L _II or L _III is bonded to formula (I) through a R ₀ ' group, and one end of the R ₀ ' group is bonded to the naphthalene ring in the structural unit where it is located combined, the other end is bonded with formula (I);

* in the monovalent group represented by the formula (IV) represents a binding end bonded to L _I , L _II or L _III ; In formula (IV), n is an integer between 1 and 10, preferably an integer between 1 and 5, more preferably an integer between 1 and 3; R ₀ is selected from n-valent C _1-30 straight chain or Branched alkyl, C _2-30 linear or branched heteroalkyl, preferably selected from n-valent C _1-20 linear or branched alkyl, C _2-20 linear or branched heteroalkyl, more It is preferably selected from n-valent C _1-10 linear or branched alkyl, C _2-10 linear or branched heteroalkyl; each R ₀ ' group is independently selected from C _1-6 linear or branched Chain alkylene, preferably selected from C _1-4 linear or branched alkylene, more preferably selected from C _1-3 linear or branched alkylene; each R' group is independently selected from C _{1 ~10} linear or branched alkylene, preferably selected from C _1-5 linear or branched alkylene, more preferably selected from C _1-3 linear or branched alkylene; each R" group is independently Independently selected from C _1-30 straight-chain or branched alkyl, preferably from C _1-20 straight or branched alkyl, more preferably from C _1-10 straight or branched alkyl; each R" The ' groups are each independently selected from C _1-30 straight-chain or branched-chain alkyl groups, preferably from C _1-20 straight-chain or branched-chain alkyl groups, more preferably from C _1-10 straight-chain or branched-chain alkyl groups . 2. ester compound according to claim 1, is characterized in that, In formula (II), when m=1, one of L _I , L _II , and L _III is a binding end bonded to formula (I) through a R ₀ ' group, and the other two are each independently H , C _1-4 alkyl or a monovalent group represented by formula (IV), one end of the R ₀ ' group is bonded to the naphthalene ring in the structural unit where it is located, and the other end is bonded to formula (I); In formula (II), when m=2, there are two structural units as shown in formula (III), and only one L _I , L _II or L _III exists between the two structural units through each other through R ₀ ' group bonding; In formula (II), when m is greater than 2, there are m structural units as shown in formula (III), and m structural units are structural units at one end that are sequentially bonded through R ₀ ' groups, (m-2) middle structural units and another end structural unit, and only one L _I , L _II or L _III and the adjacent middle structural unit exists in each end structural unit The L _I , L _II or L _III are bonded through the R ₀ ' group, and there are 2 L _I , L _II or L _III in each structural unit in the middle and L _I , L II or L III in the adjacent structural unit respectively. L _II or L _III is bonded through the R ₀ ' group. 3. ester compound according to claim 1 is characterized in that, the group shown in formula (II) comprises:

wherein * represents the binding end bonded to the formula (I) through the R ₀ ' group. 4. The ester compound according to claim 1, wherein the ester compound comprises:

wherein the group AN represents a group of formula (II). 5. An antioxidant composition, comprising the ester compound described in one of claims 1 to 4 and the compound represented by formula (II');

Formula (II') is a compound in which m structural units represented by formula (III') are bonded to each other through R ₀ ' groups,

In formula (II'), m is an integer between 1 and 10, preferably an integer between 1 and 5, more preferably an integer between 1 and 3; each R _I group is independently selected from H, C _1-10 linear or branched alkyl, preferably selected from H, C _1-5 linear or branched alkyl, more preferably selected from H, C _1-3 linear or branched alkyl; each x is independently is independently selected from an integer between 0 and 4, preferably an integer between 0 and 2, more preferably 0 or 1; each R _II group is independently selected from H, C _1-10 straight or branched chain alkyl, It is preferably selected from H, C _1-5 linear or branched chain alkyl, more preferably selected from H, C _1-3 linear or branched alkyl; each y is independently selected from an integer between 0 and 4, An integer between 0 and 2 is preferred, and 0 or 1 is more preferred; each R _III group is independently selected from H, C _1-10 linear or branched alkyl, preferably H, C _1-5 linear or branched alkyl, more preferably selected from H, C _1-3 straight or branched alkyl; each z is independently selected from an integer between 0 and 4, preferably an integer between 0 and 2, more preferably 0 or 1; Each of L _I ', L _II ', and L _III ' in the formula (II') is independently H, C _1-4 alkyl, and passes through L _I ', L _II ', and L _III ' in different structural units. The binding end to which the R ₀ ' group is bonded. According to the present invention, preferably, in formula (II'), L _I ', L _II ', and L _III ' in the same structural unit are not bonded to each other through R ₀ ' groups. 6. The antioxidant composition according to claim 5, characterized in that: In formula (II'), when m=1, L _I ', L _II ', L _III ' are each independently H or C _1-4 alkyl; In formula (II'), when m=2, there are two structural units as shown in formula (III'), and only one L _I ', L _II ' or L _III ' exists between the two structural units bonded to each other through the R ₀ 'group; In the formula (II'), when m is greater than 2, there are m structural units as shown in the formula (III'), and the m structural units are the structure of one end that is sequentially bonded through the R ₀ ' group unit, (m-2) intermediate structural units and another end structural unit, each end structural unit has only one L _I ', L _II ' or L _III ' and its adjacent L _I ', L _II ' or L _III ' in the middle structural unit is bonded through the R ₀ ' group, and there are 2 L _I ', L _II ' or L _III ' in each middle structural unit, respectively and with L _I ', L _II ' or L _III ' in the adjacent structural units are bonded through the R ₀ ' group. 7. The antioxidant composition according to claim 5, wherein the compound represented by formula (II') comprises:

8. The antioxidant composition according to claim 5, wherein the mass ratio between the ester compound and the compound represented by formula (II') is 1:0.1-5. 9. Use of the ester compound according to any one of claims 1 to 4 as a high temperature antioxidant. 10. Use of the antioxidant composition according to any one of claims 5 to 8 as a high temperature antioxidant or a free radical scavenger. 11. A lubricating oil composition comprising a lubricating base oil, the ester compound of any one of claims 1-4, or the antioxidant composition of any one of claims 5-8. 12. The preparation method of an ester compound, comprising the step of reacting a compound represented by formula (X), a compound represented by formula (Y), a compound represented by formula (Z) and/or a polymer thereof;

In formula (X), n is an integer between 1 and 10, preferably an integer between 1 and 5, more preferably an integer between 1 and 3; R ₀ is selected from n-valent C _1-30 straight chain or Branched alkyl, C _2-30 linear or branched heteroalkyl, preferably selected from n-valent C _1-20 linear or branched alkyl, C _2-20 linear or branched heteroalkyl, more It is preferably selected from n-valent C _1-10 linear or branched chain alkyl, C _2-10 linear or branched heteroalkyl; each R' group is independently selected from C _1-10 linear or branched chain Alkylene, preferably selected from C _1-5 linear or branched alkylene, more preferably selected from C _1-3 linear or branched alkylene; each R" group is independently selected from C _{1- 30} straight-chain or branched-chain alkyl groups, preferably selected from C _1-20 straight-chain or branched-chain alkyl groups, more preferably C _1-10 straight-chain or branched-chain alkyl groups; each R"' group is independently selected From C _1-30 straight-chain or branched alkyl, preferably from C _1-20 straight or branched alkyl, more preferably from C _1-10 straight or branched alkyl; In formula (Y), each R _I group is independently selected from H, C _1-10 linear or branched alkyl, preferably H, C _1-5 linear or branched alkyl, more preferably selected from H, C _1-3 straight or branched chain alkyl; each x is independently selected from an integer between 0 and 4, preferably an integer between 0 and 2, more preferably 0 or 1; each R _II group Each group is independently selected from H, C _1-10 linear or branched chain alkyl, preferably selected from H, C _1-5 linear or branched alkyl, more preferably selected from H, C _1-3 linear or branched chain alkyl; each y is independently selected from an integer between 0 and 4, preferably an integer between 0 and 2, more preferably 0 or 1; each R _III group is independently selected from H, C _{1~ 10} Linear or branched alkyl, preferably selected from H, C _1-5 linear or branched alkyl, more preferably selected from H, C _1-3 linear or branched alkyl; each z is independently selected An integer from 0 to 4, preferably an integer from 0 to 2, more preferably 0 or 1; In formula (Z), R ₀ " groups are each independently selected from H, C _1-5 straight-chain or branched alkylene, preferably H, C _1-3 straight or branched alkylene, More preferably selected from H and C _1-2 alkylene. 13 . The method according to claim 12 , wherein the compound represented by the formula (X) is selected from the esterification products of monohydric alcohols and/or polyhydric alcohols of C _1～18 and fatty acids of C _{3～20 . 13} . C _1-18 polyols include one or more of ethylene glycol, trimethylolpropane, pentaerythritol, dipentaerythritol and tripentaerythritol, and the C _3-20 fatty acids include valeric acid, isovaleric acid, hexamethylene One or more of acid, heptanoic acid, octanoic acid, isooctanoic acid, 2-ethylhexanoic acid, nonanoic acid, 3,5,5-trimethylhexanoic acid, capric acid, lauric acid, palmitic acid and oleic acid . 14. The method according to claim 12, wherein the compound shown in the formula (X) is one or more of trimethylolpropane, pentaerythritol, dipentaerythritol and saturated fatty acid of C _3～20 The esterification product (preferably one or more of trimethylolpropane ester, pentaerythritol ester and dipentaerythritol ester with kinematic viscosity at 100°C of (3.6-4.2) mm ² /s). 15. The method according to claim 12, characterized in that, the mass ratio between the compound represented by formula (X) and the compound represented by formula (Y) is 1:0.1-5; represented by formula (Y) The molar ratio between the compound, the compound represented by the formula (Z) and/or its multipolymer is 1:0.3-2.0; the compound represented by the formula (X), the compound represented by the formula (Y), the compound represented by the formula (Z) The temperature at which the compound and/or its polymer react is 60-120°C. 16 . The method according to claim 12 , wherein, in the compound represented by formula (Y), the 4 and 6 positions of the naphthalene ring to which the amine group is connected are hydrogen atoms. 17 . 17. The method according to claim 12, wherein the compound represented by the formula (X) is selected from one or more of the following compounds: trimethylolpropane saturated ester, pentaerythritol saturated ester, bis Pentaerythritol saturated ester, isooctyl di-n-decanoate; and/or, The compound represented by formula (Y) is selected from one or more of the following compounds: N-(p-tert-butylphenyl)-1-naphthylamine, N-(p-tert-octylphenyl)-1 -naphthylamine, N-(p-phenethylphenyl)-1-naphthylamine, N-phenyl-1-naphthylamine; and/or, the compound represented by formula (Z) is selected from one of the following compounds One or more: one or more of formaldehyde, paraformaldehyde, acetaldehyde, benzaldehyde and parabenzaldehyde. 18. according to the described method of claim 12, it is characterized in that, add catalyst in the reaction of compound shown in (X), compound shown in formula (Y), compound shown in formula (Z) and/or its multipolymer (The catalyst is preferably an acidic catalyst, more preferably one or more of glacial acetic acid, acetic acid, sulfuric acid, hydrochloric acid, phosphoric acid, SO ₃ and P ₂ O ₅ or an aqueous solution of these substances and mixtures thereof). 19. according to the described method of claim 12, it is characterized in that, the reaction of compound shown in formula (X), compound shown in formula (Y), compound shown in formula (Z) and/or its polymer is in inert gas. under protection. 20. A method for improving the antioxidative and anticorrosion properties of a lubricating oil composition, comprising mixing the ester compound according to one of claims 1 to 4 or the ester compound prepared according to one of claims 12 to 19 or the ester compound according to one of claims 5 to 5 The antioxidant composition of one of 8 was added to the lubricating base oil.

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