CN114479988A

CN114479988A - Antioxidant composition and preparation method thereof

Info

Publication number: CN114479988A
Application number: CN202111207952.7A
Authority: CN
Inventors: 唐红金; 梁宇翔; 尹开吉; 贺景坚; 刘辉; 王玉睿涵
Original assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Current assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Priority date: 2020-10-27
Filing date: 2021-10-18
Publication date: 2022-05-13
Anticipated expiration: 2041-10-18

Abstract

The invention provides an antioxidant composition, a preparation method thereof and a lubricating oil composition containing the antioxidant composition. The antioxidant composition comprises an ester compound, a multifunctional oiliness agent and an optional amine compound, wherein the structure of the ester compound is shown as the formula (I):

in formula (I), at least one A group is selected from 1-valent groups shown in formula (II);

Description

Antioxidant composition and preparation method thereof

Technical Field

The invention relates to an antioxidant composition, in particular to an antioxidant composition which can be used in aviation synthetic ester lubricating oil and has high-temperature oxidation and corrosion resistance.

Background

The high-temperature corrosion and oxidation stability of the aircraft engine lubricating oil are important manifestations of the high-temperature oxidation resistance of the aircraft engine oil. The lubricating oil is subjected to a series of chemical changes under the action of high-temperature oxygen induction and metal catalysis for a long time, so that a large amount of sediments such as oil sludge and the like are generated, and the normal working operation of the aero-engine is seriously influenced. The improvement of the high-temperature corrosion and oxidation stability of the aircraft engine oil has important significance for improving the working efficiency and the service life of lubricating system equipment.

With the development of the aviation industry and the improvement of the flying speed of airplanes, the use temperature of a main body of the turbojet engine lubricating oil is increased from 80 ℃ in the early stage to 220 ℃ at present, when the outlet temperature of the aero engine oil is more than 200 ℃, the oxidation speed of the common engine lubricating oil is multiplied, so that the viscosity of the lubricating oil is increased, the total acid value is increased, the corrosivity is strong, and a large amount of sediments are generated. To effectively alleviate these problems, it is necessary to improve the high temperature corrosion and oxidation stability of aircraft engine lubricating oils.

The high-temperature corrosion and oxidation stability of the aircraft engine oil are closely related to the structures and high-temperature properties of the base oil and the antioxidant. Therefore, the high-temperature corrosion and oxidation stability of the aircraft engine oil is effectively improved, and a high-temperature oxidation and corrosion inhibitor with excellent chemical structure and high-temperature oxidation resistance needs to be synthesized, so that the problems of oil quality deterioration and deposition of the aircraft engine lubricating oil under the high-temperature condition are effectively solved.

Four centistokes (4 mm) with a kinematic viscosity rating of four centistokes at 100 ℃ in the international famous aviation lubricant specification MIL-PRF-7808L specification²And/s) the aircraft engine lubricating oil simultaneously requires good high-temperature oxidation resistance and low-temperature fluidity, thereby ensuring the rapid flight of the aircraft under high temperature, high rotating speed and high load, and ensuring the rapid take-off, flexible maneuvering, high-speed cruising and safe landing of the aircraft in alpine regions. The high-temperature antioxidant with excellent chemical structure and high-temperature antioxidant performance needs to be synthesized, so that the base oil can be effectively protected, the generation of oxidation products is reduced, the sediment is reduced, the deterioration and the sediment problems of the high-temperature oil of the aircraft engine oil are effectively relieved, and the high-temperature safe and stable operation of the aircraft engine is ensured. Meanwhile, the lubricating oil composition has lower kinematic viscosity and better low-temperature fluidity at low temperature, and the kinematic viscosity is less than or equal to 20000 (mm) at the temperature of-51 ℃ in accordance with the MIL-PRF-7808L specification²The index requirement of/s) is more favorable for the low-temperature lubrication service of lubricating oil and the safe and quick start and flight of the aviation aircraft in a low-temperature environment.

Disclosure of Invention

The invention provides an antioxidant composition, a preparation method thereof and a lubricating oil composition containing the antioxidant composition, which comprises the following aspects.

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

The antioxidant composition comprises an ester compound, a multifunctional oiliness agent and an optional amine compound.

According to the invention, the structure of the ester compound is shown as the formula (I):

in the formula (I), n is an integer between 1 and 10, preferably an integer between 1 and 5, and more preferably an integer between 1 and 3; r₀Selected from the group consisting of n-valent C_1～30Straight or branched alkyl, C_2～30Straight-chain or branched heteroalkyl, preferably selected from the group consisting of n-valent C_1～20Straight or branched alkyl, C_2～20A linear or branched heteroalkyl radical, more preferably selected from the group consisting of n-valent C_1～10Straight or branched alkyl, C_2～10A linear or branched heteroalkyl group; each R' group is independently selected from C_1～10Straight-chain or branched alkylene, preferably selected from C_1～5Straight or branched alkylene, more preferably selected from C_1～3A linear or branched alkylene group; each R' group is independently selected from C_1～30Straight or branched alkyl, preferably selected from C_1～20Straight or branched alkyl, more preferably selected from C_1～10A linear or branched alkyl group; each R' "group is independently selected from C_1～30Straight or branched alkyl, preferably selected from C_1～20Straight or branched alkyl, more preferably selected from C_1～10A linear or branched alkyl group; each A group is selected from the group represented by formula (II), H, C_1～20A linear or branched alkyl group, preferably selected from the group represented by formula (II), H, C_1～10A linear or branched alkyl group, more preferably selected from the group represented by the formula (II), H, C_1～5A linear or branched alkyl group, and at least one A group in formula (I) is selected from the group consisting of 1-valent group represented by formula (II) wherein the 1-valent group represented by formula (II) is represented by R₀' group is bonded to formula (I), R₀' group is selected from C_1～6A linear or branched alkylene group;

the formula (II) is that m structural units shown as the formula (III) mutually pass through R₀' group bonding to form a 1-valent radical, wherein R is present₀' the groups are each independently selected from C_1～6Straight-chain or branched alkylene, preferably selected from C_1～4Straight or branched alkylene, more preferably selected from C_1～3A linear or branched alkylene group;

in the formula (II), m is an integer between 1 and 10, preferably an integer between 1 and 5, and more preferably an integer between 1 and 3; each R is_IEach independently selected from H, C_1～10Straight or branched chain alkyl, preferably selected from H, C_1～5Straight or branched chain alkyl, more preferably selected from H, C_1～3A linear or branched alkyl group; 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 is_IIEach independently selected from H, C_1～10Straight or branched chain alkyl, preferably selected from H, C_1～5Straight or branched chain alkyl, more preferably selected from H, C_1～3A linear or branched alkyl group; 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 is_IIIEach independently selected from H, C_1～10Straight or branched chain alkyl, preferably selected from H, C_1～5Straight or branched chain alkyl, more preferably selected from H, C_1～3A linear or branched alkyl group; 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 L in the formula (II)_I、L_II、L_IIIEach independently is H, C_1～10Alkyl, and L in different structural units_I、L_IIOr L_IIIBy R₀' bonding end of group bonding, through R₀' bonding end of group to formula (I), 1-valent group represented by formula (IV) (preferably H, C)_1～4Alkyl, and L in different structural units_I、L_IIOr L_IIIBy R₀' bonding end of group bonding, through R₀' bonding end of group bonded to formula (I), represented by formula (IV)A 1-valent group of (1); in which each R present₀' the groups are each independently selected from C_1～6Straight-chain or branched alkylene, preferably selected from C_1～4Straight or branched alkylene, more preferably selected from C_1～3A linear or branched alkylene group;

in formula (II) there is only one L_I、L_IIOr L_IIIThrough reaction with R₀' A group is bonded to formula (I), R₀One end of the group is bonded to the naphthalene ring in the structural unit in which it is located, and the other end is bonded to formula (I);

in the 1-valent group represented by the formula (IV), represents and L_I、L_IIOr L_IIIA bonded bonding end;

in the formula (IV), n is an integer between 1 and 10, preferably an integer between 1 and 5, and more preferably an integer between 1 and 3; r₀Selected from the group consisting of n-valent C_1～30Straight or branched alkyl, C_2～30Straight-chain or branched heteroalkyl, preferably selected from the group consisting of n-valent C_1～20Straight or branched alkyl, C_2～20A linear or branched heteroalkyl radical, more preferably selected from the group consisting of n-valent C_1～10Straight or branched alkyl, C_2～10A linear or branched heteroalkyl group; each R is₀' the groups are each independently selected from C_1～6Straight or branched alkylene, preferably selected from C_1～4Straight or branched alkylene, more preferably selected from C_1～3A linear or branched alkylene group; each R' group is independently selected from C_1～10Straight-chain or branched alkylene, preferably selected from C_1～5Straight or branched alkylene, more preferably selected from C_1～3A linear or branched alkylene group; each R' group is independently selected from C_1～30Straight or branched alkyl, preferably selected from C_1～20Straight or branched alkyl, more preferably selected from C_1～10A linear or branched alkyl group; each R' "group is independently selected from C_1～30Straight or branched alkyl, preferably selected from C_1～20Straight or branched chain alkyl, morePreferably selected from C_1～10Straight or branched chain alkyl.

According to the invention, preferably, in formula (II), L in the same structural unit_I、L_II、L_IIIAre not mutually passed through R₀' group bonding.

According to the invention, in formula (II), when m is 1, L_I、L_II、L_IIIIs through R₀' the bonding end of the group to which the formula (I) is bonded, the other two being each independently H, C_1～4Alkyl or a 1-valent group of the formula (IV)₀' one end of the group is bonded to the naphthalene ring in the structural unit in which it is located, and the other end is bonded to formula (I).

According to the invention, in formula (II), when m is 2, there are 2 structural units as shown in formula (III), L among the different structural units_I、L_II、L_III(when they are all L in different structural units_I、L_IIOr L_IIIBy R₀'bonding end of group bonding)' capable of mutually passing through R₀' group bonding, optionally, there is only one L each between 2 building blocks_I、L_IIOr L_IIIThrough each other by R₀' group bonding, i.e. by only one R between 2 building blocks₀' group bonding.

According to the invention, in formula (II), when m is greater than 2, there are m structural units represented by formula (III), L of the m structural units_I、L_II、L_III(when they are all L in different structural units_I、L_IIOr L_IIIBy R₀'bonding end of group bonding)' capable of mutually passing through R₀' group bonding, further alternatively, m building blocks are sequentially R₀' group-bonded 1 terminal structural unit, (m-2) intermediate structural units and the other 1 terminal structural unit, only one L being present in each terminal structural unit_I、L_IIOr L_IIIAnd L in the intermediate structural unit adjacent thereto_I、L_IIOr L_IIIBy R₀' group bonding, 2L in each structural unit in the middle_I、L_IIOr L_IIIL in the structural units adjacent to each other_I、L_IIOr L_IIIBy R₀' radical bonding, i.e. by only one R between two different structural units which are connected₀' group bonding.

According to the invention, examples which may be mentioned of the radicals of the formula (II) include:

5 wherein₀' the bonding end of the group to which formula (I) is bonded.

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 a group (II), and the specific molecular structure of the group (II) is shown as above. Taking (II-1) as an example, the molecular structural formula of the formed ester compound is shown as follows:

according to the invention, the multifunctional oily agent is a reaction product of alkyl benzene triazole and/or benzene triazole and mixed alkyl primary amine under the action of an acid catalyst.

According to the invention, the preparation method of the multifunctional oily agent comprises the following steps: under the existence of inert gas, the alkylbenzene triazole and/or the benzotriazole and alkyl primary amine react under the action of an acid catalyst, and a product is collected.

According to the invention, the structure of the alkylbenzene triazole and/or the benzene triazole is as follows:

in the formula R₁' selected from H, C₁～C₁₂Straight or branched alkyl, preferably C₁～C₈Straight or branched chain alkyl, most preferably methyl.

According to the invention, the primary alkylamine is C₁₆～C₂₂The primary alkyl amine of the formula R₂’CH₂NH₂Wherein R is₂' is C₁₅～C₂₁Linear or branched alkyl.

According to the invention, the primary alkylamine is preferably C₁₆～C₂₂The mixed primary alkyl amine of (1), which is a mixture of a linear primary amine and a branched primary amine.

According to the invention, based on the total mole number of the mixed alkyl primary amine, the alkyl is divided into the following components in mole percentage: said C₁₆～C₂₂The mixed alkyl primary amine of (1) contains 55 to 90 percent of C₁₆～C₂₂Linear alkyl primary amine and 10-45% of C₁₆～C₂₂Preferably contains 55% to 80% of C₁₆～C₂₂Linear alkyl primary amine and 20-45% of C₁₆～C₂₂Branched primary alkyl amines of (1).

According to the invention, based on the total mole number of the mixed alkyl primary amine, the carbon-containing fraction is as follows in mole percentage: said C₁₆～C₂₂Mixed primary alkyl amines of (1)₁₆～C₁₈The content of alkyl primary amine is 45-85 percent, C₁₉～C₂₂The content of the primary alkylamine of (2) is 15% to 55%, preferably C₁₆～C₁₈The content of alkyl primary amine is 55-75 percent, C₁₉～C₂₂The content of alkyl primary amine is 25-45%.

According to the inventionAnd (2) taking the total mole number of the mixed alkyl primary amine as a reference, and dividing the total mole number into the following components in percentage by mole: in said C₁₆～C₂₂In the mixed alkyl primary amines of (1), C₁₆～C₁₈The content of the linear primary amine is 40 to 70 percent, C₁₉～C₂₂The content of the linear primary amine is 15-40%, C₁₆～C₁₈The content of branched primary amine is 5-35 percent, C₁₉～C₂₂The content of the branched primary amine is 5 to 30 percent; preferably C₁₆～C₁₈The content of the linear primary amine is 45 to 60 percent, C₁₉～C₂₂The content of the linear primary amine is 20 to 35 percent, C₁₆～C₁₈The content of branched primary amine is 5-25%, C₁₉～C₂₂The content of the branched primary amine is 5 to 30 percent.

According to the invention, the acidic catalyst is preferably glacial acetic acid, sulfuric acid, hydrochloric acid, phosphoric acid, SO₃And P₂O₅Preferably sulfuric acid and/or glacial acetic acid or an aqueous solution thereof, most preferably glacial acetic acid or acetic acid in a mass percentage of 60% to 100%.

According to the invention, the molar ratio between the alkylbenzotriazole and/or benzotriazole and the primary alkylamine is 1: 0.5 to 1, preferably 1: 0.8 to 1.

According to the invention, the mass ratio of the acidic catalyst to the alkylbenzene triazole and/or the benzene triazole is 1: 0.5 to 5, preferably 1: 0.8 to 4.

According to the invention, the reaction temperature of the alkyl benzene triazole and/or the benzene triazole and the alkyl primary amine under the action of the acid catalyst is 60-100 ℃, preferably 80-100 ℃, and the reaction time is usually better as long as possible, generally 2-8 h, preferably 3-6 h.

According to the invention, in the antioxidant composition, the mass ratio of the ester compound to the multifunctional oily agent is 10-60: 1, preferably 15 to 50: 1.

according to the invention, the antioxidant composition optionally comprises an amine compound selected from compounds represented by formula (II'):

the formula (II ') is m structural units shown as the formula (III') mutually pass through R₀' the compound formed by bonding the groups,

in formula (II'), m is an integer of 1 to 10, preferably an integer of 1 to 5, more preferably an integer of 1 to 3; each R is_IEach independently selected from H, C_1～10Straight or branched chain alkyl, preferably selected from H, C_1～5Straight or branched chain alkyl, more preferably selected from H, C_1～3A linear or branched alkyl group; 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 is_IIEach independently selected from H, C_1～10Straight or branched chain alkyl, preferably selected from H, C_1～5Straight or branched chain alkyl, more preferably selected from H, C_1～3A linear or branched alkyl group; 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 is_IIIEach independently selected from H, C_1～10Straight or branched chain alkyl, preferably selected from H, C_1～5Straight or branched chain alkyl, more preferably selected from H, C_1～3A linear or branched alkyl group; 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 L in the formula (II')_I’、L_II’、L_III' independently of each other is H, C_1～4Alkyl, and L in different structural units_I’、L_II’、L_IIIBy R₀' bonding end of group linkage.

According to the invention, preferably, in formula (II'), L in said same structural unit_I’、L_II’、L_III' do not pass through R each other₀' group bonding.

According to the invention, in formula (II'), when m ═ 1, L_I’、L_II’、L_III' each independently is H or C_1～4An alkyl group.

According to the invention, in formula (II '), when m is 2, there are 2 structural units as shown in formula (III'), L among the different structural units_I’、L_II’、L_III' (when they are all L in different structural units_I’、L_II’、L_IIIBy R₀' when the bonding end of the group bonds) can be bonded to each other, preferably, only one L is present between each of the 2 structural units_I’、L_II' or L_III' mutually through R₀' radical bonding, i.e. the bonding between 2 different structural units via only one R₀' group bonding.

According to the invention, in formula (II '), when m is greater than 2, there are m structural units represented by formula (III'), L in different structural units_I’、L_II’、L_III' (when they are all L in different structural units_I’、L_II’、L_IIIBy R₀'bonding end of group bonding)' capable of mutually passing through R₀' group bonding, further alternatively, m building blocks are sequentially R₀' group-bonded 1 terminal structural unit, (m-2) intermediate structural units and the other 1 terminal structural unit, only one L being present in each terminal structural unit_I’、L_II' or L_III' and L in the intermediate structural unit adjacent thereto_I’、L_II' or L_IIIBy R₀' group bonding, 2L in each structural unit in the middle_I’、L_II' or L_III' L in the respective structural units adjacent thereto_I’、L_II' or L_IIIBy R₀' radical bonding, i.e. by only one R between two different structural units which are connected₀' baseAnd (4) bonding the clusters.

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

according to the present invention, preferably, the mass ratio between the ester compound and the optional amine compound is 1: 0.1 to 5, more preferably 1: 0.3 to 3.

The antioxidant composition can obviously improve the oxidation stability and high-temperature corrosion resistance of lubricating oil, particularly synthetic lubricating oil, and is particularly suitable for aviation synthetic ester lubricating oil.

According to the present invention, the method for preparing the ester compound comprises 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 the formula (X), n is an integer between 1 and 10, preferably an integer between 1 and 5, and more preferably an integer between 1 and 3; r₀Selected from the group consisting of n-valent C_1～30Straight or branched alkyl, C_2～30Straight-chain or branched heteroalkyl, preferably selected from the group consisting of n-valent C_1～20Straight or branched alkyl, C_2～20A linear or branched heteroalkyl radical, more preferably selected from the group consisting of n-valent C_1～10Straight or branched alkyl, C_2～10A linear or branched heteroalkyl group; each R' group is independently selected from C_1～10Straight-chain or branched alkylene, preferably selected from C_1～5Straight or branched alkylene, more preferably selected from C_1～3A linear or branched alkylene group; each R' group is independently selected from C_1～30Straight or branched alkyl, preferably selected from C_1～20Straight or branched alkyl, more preferably selected from C_1～10A linear or branched alkyl group; each R' "group is independently selected from C_1～30Straight or branched alkyl, preferably selected from C_1～20Straight or branched alkyl, more preferably selected from C_1～10A linear or branched alkyl group;

in the formula (Y), each R_IEach independently selected from H, C_1～10Straight or branched chain alkyl, preferably selected from H, C_1～5Straight or branched chain alkyl, more preferably selected from H, C_1～3A linear or branched alkyl group; 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 is_IIEach independently selected from H, C_1～10Straight or branched chain alkyl, preferably selected from H, C_1～5Straight or branched chain alkyl, more preferably selected from H, C_1～3A linear or branched alkyl group; 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 is_IIIEach independently selected from H, C_1～10Straight or branched chain alkyl, preferably selected from H, C_1～5Straight or branched chain alkyl, more preferably selected from H, C_1～3A linear or branched alkyl group; each z is independently selected from an integer between 0 and 4, preferably an integer between 0 and 2, more preferably 0 or 1;

in the formula (Z), R₀Each "group is independently selected from H, C_1～5Linear or branched alkylene, preferably selected from H, C_1～3Straight or branched alkylene, more preferably selected from H, C_1～2An alkylene group.

According to the invention, the compound of formula (X) is preferably selected from C_1～18With C_3～20Esterification products of fatty acids, said C_1～18The polyhydric alcohol of (A) comprises one or more of ethylene glycol, trimethylolpropane, pentaerythritol, dipentaerythritol and tripentaerythritol, and the C is_3～20The fatty acid of (a) includes one or more of valeric acid, isovaleric acid, caproic acid, enanthic acid, caprylic acid, isooctanoic acid, 2-ethylhexanoic acid, pelargonic 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 one or more of trimethylolpropane, pentaerythritol and dipentaerythritol and C_3～20Further preferably 100 ℃ of the esterification product of saturated fatty acidThe dynamic viscosity is (3.6-4.2) mm²One or more of trimethylolpropane ester, pentaerythritol ester and dipentaerythritol ester per second.

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

according to 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 to 5, more preferably 1: 0.3 to 3;

according to the invention, the molar ratio between the compound of formula (Y), the compound of formula (Z) and/or the polymers thereof is preferably 1: 0.3 to 2.0, more preferably 1: 0.75 to 1.5; the temperature 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 the polymer thereof is preferably 60-120 ℃, and more preferably 70-110 ℃; the absolute pressure 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 the polymer thereof are reacted is not particularly limited, but is preferably 0.01MPa to 0.12MPa, more preferably 0.01MPa to 0.10 MPa.

According to 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 the polymer thereof is preferably as long as the reaction proceeds smoothly, and is usually preferably from 1 to 10 hours, more preferably from 2 to 6 hours.

According to the present invention, it is preferable that in the compound represented by the formula (Y), the 4, 6-positions of the naphthalene ring to which the amine group is attached are hydrogen atoms.

According to the present invention, preferably, the compound represented by formula (X) may be selected from one or more of the following compounds: trimethylolpropane saturated acid ester, pentaerythritol saturated acid ester, dipentaerythritol saturated acid ester and di-n-decanoic acid isooctyl ester.

According to the present invention, preferably, the compound represented by formula (Y) may be selected from one or more of the following compounds: n-p-tert-butyl-phenyl-1-naphthylamine, N- (p-tert-octylphenyl) -1-naphthylamine, N-p-phenethyl-phenyl-1-naphthylamine, N-phenyl-1-naphthylamine.

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

According to the present invention, a catalyst may or may not be added, preferably a catalyst is 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 the polymer thereof. The catalyst is preferably an acidic catalyst. The acidic catalyst can be glacial acetic acid, sulfuric acid, hydrochloric acid, phosphoric acid, SO₃And P₂O₅Preferably sulfuric acid and/or glacial acetic acid or an aqueous solution thereof, most preferably glacial acetic acid or an acetic acid solution with a mass percentage of 60% to 100%. The amount of the catalyst added is preferably 3 to 20% of the amount of the compound represented by the formula (X). The catalyst can be removed by vacuum distillation and alkali washing and water washing.

According to the invention, the reaction of the compound of formula (X), the compound of formula (Y), the compound of formula (Z) and/or polymers thereof is preferably carried out under a blanket of an inert gas, preferably nitrogen.

According to 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 the polymer thereof. The solvent is preferably C₆～C₂₀Alkanes, most preferably C₆～C₁₀Alkanes, such as n-decane, n-heptane, cyclohexane. The solvent may be removed by a conventional method such as distillation or extraction, and is not particularly limited.

According to the invention, the reaction product of the compound shown in the formula (X), the compound shown in the formula (Y), the compound shown in the formula (Z) and/or the polymer thereof can be a single ester compound, can also be a mixture formed by a plurality of ester compounds, can also be a mixture of one or more ester compounds and one or more amine compounds, and can also be a mixture of one or more ester compounds and one or more amine compounds and the compound shown in the formula (X).

According to 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 the polymer thereof may be a single ester compound or a mixture of a plurality of ester compounds, which are all contemplated by the present invention, and the difference in the form does not affect the achievement of the effect of the present invention. Therefore, the reaction products are referred to collectively as the ester compounds without distinction in the context of the present specification. 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 ester compound of a specific structure from the reaction product. Of course, such purification or isolation is preferable for further improvement of the intended effect of the present invention, but is not essential to the present invention. As the purification or separation method, for example, the reaction product may be purified or separated by a column chromatography method, a preparative chromatography method or the like.

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 the polymer thereof may be a mixture of one or more ester compounds and one or more amine compounds. In the reaction process, the compound shown in the formula (Y) can react with the compound shown in the formula (X) and also can perform self intermolecular coupling reaction, and the self intermolecular coupling product is the compound with m larger than 1 in the compound shown in the formula (II'). The compound of formula (II ') thus includes the coupling product between the unreacted compound of formula (Y) (i.e., the compound of formula (II ') wherein m is equal to 1) and the compound of formula (Y) itself (i.e., the compound of formula (II ') wherein m is greater than 1).

According to the preparation method of the invention, when the reaction product of the compound shown in the formula (X), the compound shown in the formula (Y), the compound shown in the formula (Z) and/or the polymer thereof is a mixture of one or more ester compounds and one or more amine compounds, the amine compounds can be separated; it is also possible to use the amine compounds as a component of the antioxidant composition of the invention without isolating them.

According to the preparation method of the 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 the polymer thereof can be a mixture of one or more ester compounds and one or more amine compounds and compounds represented by the formula (X). The reaction product may contain a compound represented by the formula (X), that is, an 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 the polymer thereof is a mixture of one or more ester compounds and one or more of the amine compound and the compound represented by the formula (X), the compound represented by the formula (X) may be separated; it is also possible to use the compound of the formula (X) as an additional component without isolating the compound of the formula (X). Since the compound represented by the formula (X) is an ester compound itself, it can be used as a lubricating base oil or an antiwear agent, a friction modifier, and therefore can be used as an additional component.

According to the production method of the present invention, there may be unreacted compound of formula (Z) and/or polymer thereof in the reaction product of compound of formula (X), compound of formula (Y), compound of formula (Z) and/or polymer thereof, and the unreacted compound of formula (Z) and/or polymer thereof may be removed by a conventional method such as distillation or extraction, and is not particularly limited.

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

According to the production 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 may be subjected to a purification operation to increase the purity of the reaction product. Examples of the purification method include washing, recrystallization, and the like, and are not particularly limited.

In a second aspect, the invention provides a method for preparing the antioxidant composition.

The preparation method of the antioxidant composition comprises the step of mixing the ester compound, the multifunctional oily agent and the optional amine compound.

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

The lubricating oil composition of the invention comprises a lubricating base oil and the antioxidant composition of any one of the preceding aspects. The antioxidant composition of any one of the preceding aspects accounts for 1-20% of the total mass of the lubricating oil composition, preferably 3-15% of the total mass of the lubricating oil composition. The lubricating base oil is preferably a synthetic hydrocarbon and/or synthetic ester, more preferably C_1～10Polyol with C_3～20Esters of fatty acids of (a), C_1～10Examples of the polyhydric alcohol of (b) include one or more of trimethylolpropane, pentaerythritol, dipentaerythritol and tripentaerythritol, and (C) is_3～20Examples of the fatty acid of (2) include one or more of valeric acid, isovaleric acid, caproic acid, heptanoic acid, caprylic acid, isooctanoic acid, 2-ethylhexanoic acid, nonanoic acid, 3,5, 5-trimethylhexanoic acid, decanoic acid, and lauric acid. More preferably, the lubricating base oil is one or more of trimethylolpropane, pentaerythritol and dipentaerythritol with C_3～20The esterification product of saturated fatty acid (b) is more preferably an esterification product having a kinematic viscosity of (3 to 12) mm at 100 ℃²One or more of trimethylolpropane ester, pentaerythritol ester and dipentaerythritol ester per second. Other types of additives may also be added to the lubricating oil compositions of the present invention, such as viscosity index improvers, anti-wear agents, pour point depressants, rust inhibitors, and the like.

The lubricating oil composition has excellent oxidation stability and high-temperature corrosion resistance.

In a fourth aspect, the present invention also provides a method of improving the antioxidant and corrosion resistance of a lubricating oil composition, which comprises adding to a lubricating base oil an antioxidant composition as defined in any one of the preceding aspects.

Drawings

FIG. 1 is a high performance liquid chromatography mass spectrum of a physical mixed system of reaction raw material N- (P-tert-octylphenyl) -1-naphthylamine and ester.

FIG. 2 is a high performance liquid chromatography mass spectrum of a synthesized product A1 (i.e., N- (P-tert-octylphenyl) -1-naphthylamine-ester formaldehyde polycondensate).

FIG. 3 is an infrared spectrum of reaction product B1 (i.e., liquid alkylbenzene triazole fatty amine salt).

FIG. 4 is a nuclear magnetic spectrum of reaction product B1 (i.e., liquid alkylbenzene triazole fatty amine salt).

Detailed Description

In the context of the present specification, the expression "number + valence + group" or the like refers to a group obtained by removing the number of hydrogen atoms represented by the number from the basic structure (such as a chain, a ring, a combination thereof, or the like) to which the group corresponds, and preferably refers to a group obtained by removing the number of hydrogen atoms represented by the number from a carbon atom (preferably a saturated carbon atom and/or a non-identical carbon atom) contained in the structure. For example, "3-valent straight or branched alkyl" refers to a group obtained by removing 3 hydrogen atoms from a straight or branched alkane (i.e., the base chain to which the straight or branched alkyl corresponds), and "2-valent straight or branched heteroalkyl" refers to a group obtained by removing 2 hydrogen atoms from a straight or branched heteroalkane (preferably from a carbon atom contained in the heteroalkane, or further, from a non-identical carbon atom).

In the context of the present specification, the heteroalkyl group refers to a group obtained by interrupting the carbon chain structure of an alkyl group with one or more (e.g., 1 to 5, 1 to 4, 1 to 3, 1 to 2, or 1) hetero groups selected from the group consisting of-Sx-, -O-, and-NR "", wherein x is an integer between 1 and 5 (preferably an integer between 1 and 4, more preferably 1, 2, or 3). From the viewpoint of structural stability, it is preferable that, when a plurality of hetero groups are present, any two of the hetero groups are not directly bonded to each other. It is apparent that the hetero group is not at the end of the carbon chain of the hydrocarbyl group. For the sake of convenience of the description,the number of carbon atoms of the alkyl group prior to the interruption is still used to refer to the number of carbon atoms of the heteroalkyl group after the interruption. For example, C₄Straight chain alkyl (CH)₃-CH₂-CH₂-CH₂-) interrupted by a hetero-group-O-to obtain CH₃-O-CH₂-CH₂-CH₂-、CH₃-CH₂-O-CH₂-CH₂-or CH₃-CH₂-CH₂-O-CH₂-equal C₄The straight-chain heteroalkyl, interrupted by two hetero groups-S-, giving CH₃-S-CH₂-S-CH₂-CH₂-、CH₃-CH₂-S-CH₂-S-CH₂-or CH₃-S-CH₂-CH₂-S-CH₂-equal C₄The straight-chain heteroalkyl, interrupted by three hetero groups-S-, giving CH₃-S-CH₂-S-CH₂-S-CH₂-equal C₄A linear heteroalkyl group.

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

The main raw materials used are as follows:

antioxidant L-06, N- (p-tert-octylphenyl) -1-naphthylamine, basf-Ciba Fine Ltd, chemical purity

Antioxidant PNA, N-phenyl-1-naphthylamine, institute of petrochemical institute, Xinpu corporation, chemical purity

Antioxidant AO-150, chemical Limited of King chemical, Mixed alkyl Diphenylamine

5-Methylphenyltriazole, Shanghai chemical plant, chemical purity

C₁₆～C₂₂Alkyl primary amine monomer, purity>97% from chemical institute of Chinese academy

VANLUBEV81, 4, 4' -diisooctyl diphenylamine, Van der Bill Ltd

VANLUBENA, a mixture of 4, 4' -diisooctyl diphenylamine and pentaerythritol ester, Van der Bill

Saturated fatty acid ester of trimethylolpropane in a viscosity of 3.8mm at 100 deg.C²(s) Shadong RuijieA chemical industry co, ltd,>98％

pentaerythritol ester, Zhejiang Quzhou chemical Co., Ltd., kinematic viscosity at 100 ℃ of 5.02mm²/s，>98％

Heptalis dipentaerythritol ester, shariki chemical limited of Shandong, kinematic viscosity at 100 ═ 7mm²/s，>98％

Trimethylolpropane oleate, Shanto Ruijie chemical Co., Ltd., kinematic viscosity at 100 ℃ of 8.5mm²/s，>97％

Penricus trimethylolpropane ester, Chongqing Brand of China petrochemical great wall lubricating oil, great wall 5101 high temperature synthetic lubricating oil with kinematic viscosity of 5.05mm at 100 ℃²/s，>98％

Example 1

66.2g of N- (p-tert-octylphenyl) -1-naphthylamine are added to 72.2g of 3.8mm kinematic viscosity at 100 ℃²Adding 7.2g of paraformaldehyde into the mixed system in/s trimethylolpropane saturated fatty acid ester; heating, stirring and dissolving the mixed reaction system in a nitrogen environment, maintaining the mixed system within the range of 80 ℃, and adding 18g of reaction catalyst glacial acetic acid into the reaction system; carrying out reaction at 100 ℃ for 3h, carrying out reduced pressure distillation on the mixed reaction system at 110 ℃ and the vacuum degree of less than 500Pa for 60mins, and continuously carrying out full reduced pressure distillation at the temperature of no more than 160 ℃ and the vacuum degree of less than 500Pa for 30 mins-180 mins to obtain 142g of a reaction product A1; the reaction product A1 mainly contains the compounds of the structural formula P-1, the structural formula P-2 and the structural formula P-3, and also contains a small amount of the compounds of the structural formula II ' -1, the structural formula II ' -2 and the structural formula II ' -3, and a small amount of trimethylolpropane saturated fatty acid ester in the example.

Glacial acetic acid solution with the mass concentration of 90% is prepared. 0.3mol (35.7g) of methylbenzotriazole and 0.2mol (64.6g) of primary alkylamine were successively charged into a three-necked flask, and heated with stirring, wherein the primary alkylamine had a composition of: based on the total molar amount of the alkyl primary amine, C₁₆～C₁₈The molar percentage of primary amine is 65% in total, C₁₉～C₂₀The mole percentage of primary amine is 35 percent in total, wherein C₁₆～C₁₈、C₁₉～C₂₀The mole percentage of the linear chain primary amine is 50 percent, 20 percent in sequence, C₁₆～C₁₈、C₁₉～C₂₀The mole percentage content of the branched primary amine is 15 percent and 15 percent in sequence. When the temperature of the reaction mixture reaches 85 ℃, 20g of 90% acetic acid solution is dripped into the three-neck flask for 15min, and the reaction is carried out at 80-85 ℃ for 5 h. And after the reaction is finished, washing the upper liquid of the liquid reaction product with distilled water at the temperature of 80 ℃ to be neutral, shaking the mixed solution uniformly, standing, cooling and layering, and then carrying out temperature-controlled reduced pressure vacuum distillation on the obtained upper liquid to obtain 80g of a completely bright orange liquid reaction product, namely the multifunctional oily agent B1.

And (3) uniformly stirring the reaction product A1 and the reaction product B1 at a mass ratio of 25:1 and 40:1 respectively at a temperature of below 80 ℃, and preparing an antioxidant composition C1 and an antioxidant composition C2.

Respectively carrying out high performance liquid chromatography mass spectrometry on a physical mixed system of a reaction raw material N- (p-tert-octylphenyl) -1-naphthylamine (L06) and ester and a reaction product A1.

FIG. 1 is a high performance liquid chromatography mass spectrum of a physical mixed system of reaction raw material N- (p-tert-octylphenyl) -1-naphthylamine (L06) and ester.

As can be seen from comparative analysis, 330.9 is the mass-to-charge ratio peak of the reaction raw material N- (p-tert-octylphenyl) -1-naphthylamine in the mass spectrum of the high performance liquid chromatography of the physical mixed system of the reaction raw materials in FIG. 1; 523.8 and 551.3 are mass-to-charge ratio peaks of partial polyol ester in the polyol ester solvent oil; in the HPLC mass spectrum of reaction product A1 in FIG. 2, 895 and 916 are mass-to-charge ratio peaks of ester-aromatic amine oligomer, and 675, 1019 and 1225 are aromatic amine bimolecular polycondensate, aromatic amine trimolecular polycondensate and aromatic amine bimolecular polycondensate and ester polycondensate, respectively. In addition, there are many other mass-to-charge ratio peaks of the polycondensate molecules in FIG. 2, which well illustrates the formaldehyde polycondensation reaction between the reaction raw materials to form the novel polycondensate composition of the present invention.

The mass to charge ratios for some of the new molecules of the synthesized aromatic amine formaldehyde polycondensates are exemplified 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……

a sample of reaction product B1 was taken for infrared analysis and characterization and the infrared spectrum was shown in FIG. 3.

As can be seen from FIG. 3, 1624.59cm^-1Is a typical delta_as(NH₃ ⁺) Characteristic absorption peak at 1546.05cm^-1Is a typical delta_s(NH₃ ⁺) Characteristic absorption peak of 2959.96-2871.79 cm^-1Is typically v_NH(NH₃ ⁺) Broad and strong absorption band, especially 2959cm^-1、2871cm^-1Nearby has v_NH(NH₃ ⁺) The absorption is obvious, and the spectrogram proves that the reaction product contains a large amount of primary amine salt; 1595.28cm^-1、1463.19cm^-1V is_C＝CThe presence of a benzene ring can be judged from the characteristic absorption peak of (1); 1280.79cm^-1Is a typical aromatic primary amine v_C-NA characteristic absorption peak; and at 3500cm^-1Nearby without hydrogen v on the 1-nitrogen of benzotriazole_N-HThe spectrogram proves that no primary amine exists in the liquid product, which indicates that the benzotriazole reacts to generate the liquid alkylbenzene triazole fatty amine salt.

Sampling reaction product B1 was carried out¹HNMR nuclear magnetic analysis, the nuclear magnetic spectrum is shown in figure 4.

As can be seen from FIG. 4, the benzotriazole fatty amine salt is a liquid product¹The HNMR spectrogram has a brand-new hydrogen proton chemical shift signal peak at delta 3.198, and the benzotriazole¹HNMR spectrogram and alkyl fatty acid ammonium¹The HNMR spectrogram does not have the signal peak, the signal peak is generated after the chemical shift of alpha-H on methylene adjacent to the primary amine salt is shifted, and the reaction product contains primary amine salt with hydrogen protons according to the judgment.¹In HNMR spectrogramThe delta 1.152-delta 1.245 and the delta 0.977-delta 1.108 respectively represent chemical shift signal peaks of methyl and methylene hydrogen protons on the alkyl chain of the reaction product. Delta 7.859-delta 7.370 are chemical shifts of hydrogen protons on benzene rings of the benzotriazole.

Nuclear magnetic hydrogen spectrum of liquid alkylbenzene triazole fatty amine salt¹The HNMR spectrogram can find that chemical shift bands delta 12-delta 15 (delta 13.859) on the spectrogram disappear, which indicates that active hydrogen proton chemical shift signals on benzotriazole-NH-disappear, and active hydrogen on the 1-site nitrogen of the benzotriazole generates chemical reaction, thereby generating the liquid benzotriazole aliphatic amine salt.

Example 2

Adding 99g of N- (p-tert-octylphenyl) -1-naphthylamine into 108g of mixed polyol saturated fatty acid ester (wherein, the weight of trimethylolpropane ester is 81g, and the weight of dipentaerythritol ester is 27g), and adding 12g of paraformaldehyde into the mixed system; heating, stirring and dissolving the mixed reaction system in a nitrogen environment, maintaining the mixed system at about 90 ℃, and adding 22g of reaction catalyst glacial acetic acid into the reaction system; carrying out reaction at 90 ℃ for 4h, carrying out reduced pressure distillation on the mixed reaction system at 110 ℃ and the vacuum degree of less than 500Pa for 60mins, and continuously carrying out full reduced pressure distillation at the temperature of not more than 160 ℃ and the vacuum degree of less than 500Pa for 30 mins-180 mins to obtain 210g of a reaction product A2; the reaction product A2 mainly contains compounds with similar structures to those of the structural formula P-1, the structural formula P-2 and the structural formula P-3 (except that the ester group is the ester group of the mixed polyol saturated fatty acid ester used in the present example), and also contains a smaller amount of the compounds of the structural formula II ' -1, the structural formula II ' -2 and the structural formula II ' -3, and a small amount of the mixed polyol saturated fatty acid ester in the present example.

Glacial acetic acid solution with the mass concentration of 90% is prepared. 0.3mol (35.7g) of methylbenzotriazole and 0.1mol (64.6g) of primary alkylamine were successively charged into a three-necked flask, and heated with stirring, wherein the primary alkylamine had a composition of: based on the total molar amount of the alkyl primary amine, C₁₆～C₁₈The molar percentage of primary amine is 65% in total, C₁₉～C₂₀The mole percentage of primary amine is 35 percent in total, wherein C₁₆～C₁₈、C₁₉～C₂₀The mole percentage content of the linear chain primary amine is 45 percent and 25 percent in sequence; c₁₆～C₁₈、C₁₉～C₂₀The mole percentage content of the branched primary amine is 20 percent and 10 percent in sequence. When the temperature of the reaction mixture reaches 85 ℃, 20g of 90% acetic acid solution is dripped into the three-neck flask for 20min, and the reaction is carried out at 80-85 ℃ for 5 h. After the reaction is finished, washing the upper liquid of the liquid reaction product with distilled water at the temperature of 80 ℃ to be neutral, standing and layering the mixed solution, and then carrying out temperature-controlled reduced-pressure vacuum distillation on the obtained upper liquid to obtain 77.5g of a completely transparent bright orange liquid reaction product, namely the multifunctional oiliness agent B2;

and (3) uniformly stirring the reaction product A2 and the reaction product B2 at a mass ratio of 25:1 and 40:1 respectively at a temperature of below 80 ℃, and preparing an antioxidant composition C3 and an antioxidant composition C4.

Example 3

Adding 132g of N- (p-tert-octylphenyl) -1-naphthylamine into 156g of tetra centistokes polyol saturated fatty acid ester (wherein the mass ratio of the trimethylolpropane ester to the pentaerythritol ester to the fatty acid ester is 1:1), and adding 30g of paraformaldehyde into the mixed system; heating, stirring and dissolving the mixed reaction system in a nitrogen environment, maintaining the mixed system at about 100 ℃, and adding 30g of reaction catalyst glacial acetic acid into the reaction system; carrying out reaction at 100 ℃ for 3h, carrying out reduced pressure distillation on the mixed reaction system at 110 ℃ and the vacuum degree of less than 500Pa for 60mins, and continuously carrying out full reduced pressure distillation at the temperature of no more than 160 ℃ and the vacuum degree of less than 500Pa for 30 mins-180 mins to obtain 153.5g of a reaction product A3; the reaction product A3 contains a compound mainly comprising a structure similar to the structure of formula P-1, formula P-2, formula P-3 (except that the ester group is the ester group of the polyol saturated fatty acid ester used in this example), and also contains a smaller amount of the compound of formula II ' -1, formula II ' -2, formula II ' -3, and a smaller amount of the polyol saturated fatty acid ester used in this example.

The glacial acetic acid solution with the mass concentration of 70% is prepared. 0.15mol (17.85g) of methylbenzotriazole and 0.1mol (32.3g) of an alkyl primary amine were successively charged into a three-necked flask, and the mixture was stirredHeat, wherein the composition of the primary alkyl amine is: based on the total molar amount of the alkyl primary amine, C₁₆～C₁₈、C₁₉～C₂₀The mole percentage content of the linear chain primary amine is 40 percent and 25 percent in sequence; c₁₆～C₁₈、C₁₉～C₂₀The mole percentage content of the branched primary amine is 25 percent and 10 percent in sequence. When the temperature of the reaction mixture reaches 75 ℃, 20g of 90% acetic acid solution is dripped into the three-neck flask for 15min, and the reaction is carried out at 70-75 ℃ for 5 h. After the reaction is finished, washing the upper liquid of the liquid reaction product with distilled water at 70 ℃ to be neutral, standing and layering the mixed solution, and then carrying out temperature-controlled reduced pressure vacuum distillation on the obtained upper liquid to obtain 36.27g of a completely transparent bright orange liquid reaction product, namely the multifunctional oiliness agent B3;

and (3) uniformly stirring the reaction product A3 and the reaction product B3 at a mass ratio of 25:1 and 40:1 respectively at a temperature of below 80 ℃, and preparing an antioxidant composition C5 and an antioxidant composition C6.

Comparative antioxidant

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

Evaluation of high temperature Corrosion resistance and Oxidation stability

Respectively adding the antioxidant composition C1-C6 or the comparative antioxidants V81, L-06, phenyl-1-naphthylamine T531, thiazanthrene and tricresyl phosphate (TCP) into the mixture with the kinematic viscosity of 5.02mm at 100 DEG C²Examples 7 to 12 and comparative examples 1 to 4, in which the tricresyl phosphate was 2% by mass, were prepared by heating and stirring a pentaerythritol saturated acid ester lubricating base oil to give lubricating oil compositions. The formulation compositions of examples 7-12 and comparative examples 1-4 of lubricating oil compositions of the present invention are shown in Table 1.

The lubricating oil compositions of Table 1 were separately tested for corrosion and oxidation stability evaluation using the test method FEDSTD-791-5308 as specified in International oil Specification MIL-PRF-23699G. The experimental conditions were: introducing dry air at the constant temperature of 204 ℃ for oxidation for 72 h; the oxygen flow is 50-83 mL/min; the metal test piece is steel, silver, titanium (copper) aluminum and titanium (magnesium) with specific specifications, and the change of 25 ℃ total acid value of lubricating oil, the change of 40 ℃ viscosity and the formation amount of 100mL oil deposit before and after oxidation are examined.

The evaluation indexes of the method are as follows: the change of total acid value (delta TAN/mgKOH. g) before and after oil sample oxidation^-1) (ii) a Viscosity change at 40 ℃ (Δ Viscosity%); 100mL test oil sample Deposit formation (Deposit/mg (100mL)^-1) (ii) a The mass per unit area of the metal test piece such as copper, steel, silver, aluminum, titanium and the like. The invention evaluates the experimental result by the quality change data of the copper sheet. The test results are shown in Table 2.

TABLE 1 examples 7-12 and comparative examples 1-4 of lubricating oil compositions

Comparing the technical index requirements of the MIL-PRF-5308 evaluation method with the results of the corrosion and oxidation stability evaluation data in Table 2, it can be seen that the lubricating oil compositions of examples 7-12 of 5 centistokes grade added with the antioxidant composition of the present invention have significant advantages over the lubricating oil compositions of comparative examples in terms of sheet metal mass change, total acid value change, viscosity change rate, and deposit formation, and the high temperature oxidation resistance is significantly superior to that of comparative examples 1-4. The antioxidant composition can better control the change of the total acid value of oil products, the viscosity change rate and the generation amount of sediments before and after the oxidation of lubricating oil, and well meets the index requirements of MIL-PRF-5308 corrosion and oxidation stability.

TABLE 2 evaluation test results of high temperature corrosion and oxidation stability

The antioxidant composition has excellent high-temperature oxidation resistance and sediment formation resistance, is obviously superior to a monomer arylamine antioxidant, and cannot meet the technical index of corrosion and oxidation stability specified by the latest aviation engine oil specification MIL-PRF-23699G, namely the technical index of an MIL-PRF-5308 evaluation method.

Claims

1. An antioxidant composition comprising an ester compound, a multifunctional oily agent and optionally an amine compound; the structure of the ester compound is shown as the formula (I):

each L in the formula (II)_I、L_II、L_IIIEach independently is H, C_1～10Alkyl, and L in different structural units_I、L_IIOr L_IIIBy R₀' bonding end of group bonding, through R₀' bonding end of group to formula (I), 1-valent group represented by formula (IV) (preferably H, C)_1～4Alkyl, and L in different structural units_I、L_IIOr L_IIIBy R₀' bonding end of group bonding, through R₀' the bonding end of the group bonded to formula (I), a 1-valent group represented by formula (IV); in which each R present₀' the groups are each independently selected from C_1～6Straight or branched alkylene, preferably selected from C_1～4Straight or branched alkylene, more preferably selected from C_1～3A linear or branched alkylene group;

in the formula (IV), n is an integer between 1 and 10, preferably an integer between 1 and 5, and more preferably an integer between 1 and 3; r₀Selected from the group consisting of n-valent C_1～30Straight or branched alkyl, C_2～30Straight-chain or branched heteroalkyl, preferably selected from the group consisting of n-valent C_1～20Straight or branched alkyl, C_2～20A linear or branched heteroalkyl radical, more preferably selected from the group consisting of n-valent C_1～10Straight or branched alkyl, C_2～10A linear or branched heteroalkyl group; each R is₀' the groups are each independently selected from C_1～6Straight-chain or branched alkylene, preferably selected from C_1～4Straight or branched alkylene, more preferably selected from C_1～3A linear or branched alkylene group; each R' group is independently selected from C_1～10Straight-chain or branched alkylene, preferably selected from C_1～5Straight or branched alkylene, more preferably selected from C_1～3A linear or branched alkylene group; each R' groupEach independently selected from C_1～30Straight or branched alkyl, preferably selected from C_1～20Straight or branched alkyl, more preferably selected from C_1～10A linear or branched alkyl group; each R' "group is independently selected from C_1～30Straight or branched alkyl, preferably selected from C_1～20Straight or branched alkyl, more preferably selected from C_1～10Straight or branched chain alkyl.

2. The antioxidant composition as claimed in claim 1, wherein, in the formula (II), when m is 1, L is_I、L_II、L_IIIIs through R₀' the bonding end of the group to which the formula (I) is bonded, the other two being each independently H, C_1～4Alkyl or a 1-valent group of the formula (IV)₀One end of the group is bonded to the naphthalene ring in the structural unit in which it is located, and the other end is bonded to formula (I); in formula (II), when m is 2, there are 2 structural units represented by formula (III), and only one L exists between each of the 2 structural units_I、L_IIOr L_IIIThrough each other R₀' group bonding; in the formula (II), when m is more than 2, m structural units shown as the formula (III) exist, and the m structural units are sequentially arranged through R₀' group-bonded 1 terminal structural unit, (m-2) intermediate structural units and the other 1 terminal structural unit, only one L being present in each terminal structural unit_I、L_IIOr L_IIIAnd L in the intermediate structural unit adjacent thereto_I、L_IIOr L_IIIBy R₀' group bonding, 2L in each structural unit in the middle_I、L_IIOr L_IIIL in the structural units adjacent to each other_I、L_IIOr L_IIIBy R₀' group bonding.

3. The antioxidant composition of claim 1, wherein the ester compound comprises:

wherein the group AN represents a group of formula (II).

4. The antioxidant composition as claimed in claim 1, wherein the multifunctional oily agent is a reaction product of alkylbenzotriazole and/or benzotriazole, mixed alkyl primary amine under the action of an acidic catalyst.

5. The antioxidant composition as claimed in claim 4, wherein the multifunctional oily agent is prepared by the method comprising: under the existence of inert gas, the alkylbenzene triazole and/or the benzotriazole and alkyl primary amine react under the action of an acid catalyst, and a product is collected.

6. The antioxidant composition of claim 4 or 5, wherein the alkylbenzotriazole and/or benzotriazole has the structure:

in the formula R₁' selected from H, C₁～C₁₂Straight or branched alkyl, preferably C₁～C₈Straight or branched chain alkyl, most preferably methyl;

the alkyl primary amine is C₁₆～C₂₂The primary alkyl amine of the formula R₂’CH₂NH₂Wherein R is₂' is C₁₅～C₂₁Linear or branched alkyl of (a); the acidic catalyst is glacial acetic acid, sulfuric acid, hydrochloric acid, phosphoric acid, SO₃And P₂O₅Or an aqueous solution of one or more of these substances and mixtures thereof.

7. The antioxidant composition as claimed in claim 4 or 5, wherein the primary alkylamine is C₁₆～C₂₂Mixed alkyl of (2)Primary amines.

8. The antioxidant composition as claimed in claim 7, wherein the molar percentage based on the total moles of the mixed alkyl primary amine is: said C₁₆～C₂₂The mixed alkyl primary amine of (1) contains 55 to 90 percent of C₁₆～C₂₂Linear alkyl primary amine and 10-45% of C₁₆～C₂₂Preferably contains 55% to 80% of C₁₆～C₂₂Linear alkyl primary amine and 20-45% of C₁₆～C₂₂Branched primary alkyl amines of (a); or, based on the total mole number of the mixed alkyl primary amine, in mole percentage, the carbon-containing ratio is as follows: said C₁₆～C₂₂Mixed primary alkyl amines of (1)₁₆～C₁₈The content of alkyl primary amine is 45-85 percent, C₁₉～C₂₂The content of the primary alkylamine of (2) is 15% to 55%, preferably C₁₆～C₁₈The content of alkyl primary amine is 55-75 percent, C₁₉～C₂₂The content of alkyl primary amine is 25 to 45 percent; or, based on the total moles of the mixed alkyl primary amine, in terms of mole percentage, according to the type of the alkyl group containing carbon number: in said C₁₆～C₂₂In the mixed alkyl primary amines of (1), C₁₆～C₁₈The content of the linear primary amine is 40 to 70 percent, C₁₉～C₂₂The content of the linear primary amine is 15-40%, C₁₆～C₁₈The content of branched primary amine is 5-35 percent, C₁₉～C₂₂The content of the branched primary amine is 5 to 30 percent; preferably C₁₆～C₁₈The content of the linear primary amine is 45 to 60 percent, C₁₉～C₂₂The content of the linear primary amine is 20 to 35 percent, C₁₆～C₁₈The content of branched primary amine is 5-25%, C₁₉～C₂₂The content of the branched primary amine is 5 to 30 percent.

9. The antioxidant composition as claimed in claim 4 or 5, wherein the molar ratio between the alkylbenzotriazole and/or benzotriazole and the primary alkylamine is 1: 0.5 to 1, preferably 1: 0.8 to 1; the mass ratio of the acidic catalyst to the alkylbenzene triazole and/or the benzene triazole is 1: 0.5 to 5, preferably 1: 0.8 to 4; the reaction temperature of the alkyl benzene triazole and/or the benzene triazole and the alkyl primary amine under the action of the acid catalyst is 60-100 ℃, and preferably 80-100 ℃.

10. The antioxidant composition as claimed in any one of claims 1 to 9, wherein the mass ratio of the ester compound to the multifunctional oily agent is 10 to 60: 1, preferably 15 to 50: 1.

11. antioxidant composition according to any of claims 1 to 9, characterized in that the optional amine compound is selected from the group consisting of compounds of formula (II');

in formula (II'), m is an integer of 1 to 10, preferably an integer of 1 to 5, more preferably an integer of 1 to 3; each R is_IEach independently selected from H, C_1～10Straight or branched chain alkyl, preferably selected from H, C_1～5Straight or branched chain alkyl, more preferably selected from H, C_1～3A linear or branched alkyl group; 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 is_IIEach independently selected from H, C_1～10Straight or branched chain alkyl, preferably selected from H, C_1～5Straight or branched chain alkyl, more preferably selected from H, C_1～3A linear or branched alkyl group; each y isIndependently selected from integers between 0 and 4, preferably integers between 0 and 2, more preferably 0 or 1; each R is_IIIEach independently selected from H, C_1～10Straight or branched chain alkyl, preferably selected from H, C_1～5Straight or branched chain alkyl, more preferably selected from H, C_1～3A linear or branched alkyl group; 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 L in the formula (II')_I’、L_II’、L_III' independently of each other is H, C_1～4Alkyl, and L in different structural units_I’、L_II’、L_III' by R₀' bonding end of group linkage.

12. Antioxidant composition according to claim 11, characterized in that, in formula (II'), when m is 1, L_I’、L_II’、L_III' each independently is H or C_1～4An alkyl group; in formula (II '), when m is 2, there are 2 structural units represented by formula (III'), and only one L exists between each of the 2 structural units_I’、L_II' or L_III' mutually through R₀' group bonding; in formula (II '), when m is greater than 2, m structural units represented by formula (III') are present, and m structural units are sequentially arranged through R₀' group-bonded 1 terminal structural unit, (m-2) intermediate structural units and the other 1 terminal structural unit, only one L being present in each terminal structural unit_I’、L_II' or L_III' and L in the intermediate structural unit adjacent thereto_I’、L_II' or L_IIIBy R₀' group bonding, 2L in each structural unit in the middle_I’、L_II' or L_III' L in the respective structural units adjacent thereto_I’、L_II' or L_IIIBy R₀' group bonding.

13. An antioxidant composition as claimed in claim 11, characterized in that the mass ratio between said ester compound and said amine compound is 1: 0.1 to 5.

14. The antioxidant composition as claimed in any one of claims 1 to 13, wherein the ester compound is prepared by a method comprising the step of reacting a compound represented by the formula (X), a compound represented by the formula (Y), a compound represented by the formula (Z) and/or a polymer thereof;

15. The method for preparing the antioxidant composition as claimed in any one of claims 1 to 14, comprising the step of mixing the ester compound, the multifunctional oily agent and optionally the amine compound.

16. A lubricating oil composition comprising a lubricating base oil, preferably a synthetic hydrocarbon and/or a synthetic ester, more preferably C, and the antioxidant composition of any one of claims 1 to 14_1～10Polyol with C_3～20Esters resulting from the reaction of fatty acids of (a).

17. A method of improving the oxidation and corrosion resistance of a lubricating oil composition comprising adding the antioxidant composition of any one of claims 1 to 14 to a lubricating base oil.