CN112608465B

CN112608465B - Antioxidant and preparation method thereof

Info

Publication number: CN112608465B
Application number: CN202011363432.0A
Authority: CN
Inventors: 程亮; 谢颖; 张�杰
Original assignee: Guangdong University of Petrochemical Technology
Current assignee: Guangdong University of Petrochemical Technology
Priority date: 2020-11-27
Filing date: 2020-11-27
Publication date: 2023-04-28
Anticipated expiration: 2040-11-27
Also published as: CN112608465A

Abstract

The invention discloses an antioxidant and a preparation method thereof, wherein the antioxidant is as follows:

Description

Antioxidant and preparation method thereof

Technical Field

The invention belongs to the field of additives, relates to an antioxidant for industries such as lubricating oil, engineering plastics and the like, and particularly relates to an antioxidant and a preparation method thereof.

Background

Oxidation reactions occur everywhere in our daily lives. Such as lubricating oil oxidation, plastic oxidation, glove oxidation, wire oxidation, metal oxidation, etc., which occur to cause deterioration of the product and shorten its life, resulting in a certain loss. Therefore, when developing these products, it is often necessary to add antioxidants to enhance the antioxidant capacity, thereby extending the useful life.

In either field, the antioxidant reaction mechanism can be divided into three types, radical scavenging, hydroperoxide decomposition and antioxidant synergism. Antioxidants can thus be divided into: phenolic/amine antioxidants, carbamate antioxidants, molybdate antioxidants that do not contain phosphorothioate. However, the antioxidant commonly used in the market has a narrow application range and a single function.

Disclosure of Invention

The invention aims to solve the technical problem of providing an antioxidant which has wide application range and excellent antioxidant effect.

The technical scheme adopted for solving the technical problems is as follows:

an antioxidant which is a compound of the following structure:

wherein m=0 to 100, n=0 to 100, and m and n are not zero at the same time;

R ₁ is C ₁ ～C ₁₅ Is an alkane of (a);

R ₂ is that

Wherein R is ₄ Is hydrogen or C ₁ ～C ₄ Alkane of R ₄ Is preferably C ₁ ～C ₂ Is an alkane of (a);

R ₃ is that

Wherein R is ₄ Is hydrogen or C ₁ ～C ₄ R is any integer from 1 to 20;

wherein R is ₄ Preferably C ₁ ～C ₂ R is an integer of 1 to 10.

R is

Or a combination thereof; wherein R is ₅ Is hydrogen or C ₁ ～C ₂₀ Is an alkane of (a); x is S or O; r is R ₆ 、R ₇ 、R ₈ Is hydrogen or C ₁ ～C ₅ Is an alkane of (a).

Further, among the antioxidants, R is preferable ₁ Selected from C ₁ ～C ₁₀ Is an alkane of (a).

Further, among the antioxidants, R is preferable ₂ Is benzotriazole or its derivative

Wherein R is ₄ Selected from C ₁ ～C ₂ Is an alkane of (a).

Further, among the antioxidants, R is preferable ₃ Is benzotriazole or its derivative

Wherein R is ₄ Selected from C ₁ ～C ₂ R is an integer of 1 to 10.

Further, among the antioxidants, R is preferable ₅ Selected from hydrogen or C ₁ ～C ₅ Is an alkane of (a).

Further, in the antioxidant, R is preferably selected from

The preparation method of the antioxidant comprises the following steps:

A. the raw materials are selected as follows: 40-50 parts of chloralkylene oxide, catalyst and C ₁ ～C ₁₅ 40-50 parts of alkyl alcohol compounds, benzotriazole or derivatives thereof and 40-50 parts of isocyanate compounds; 0.5-3 parts of diluent;

B. adding a catalyst into a dry reaction kettle with inert gas protection, wherein the addition amount of the catalyst is 20-100 ppm (mass ratio) of the prepared product, and then adding an initiator C ₁ ～C ₁₅ Wherein the molar ratio of the initiator to the chloroalkylene oxide is (0.1:1) - (1:5), heating the reaction kettle to 30-100 ℃, keeping the pressure below 1.5MPa, and when the temperature starts to rise and the pressure starts to fall, adopting two chloroalkylene oxides, and when the other chloroalkylene oxide is adoptedContinuously adding chlorinated alkylene oxide into a reaction kettle at the rate of 0.5-3 mL/min, continuously aging for 1-3 hours, stopping heating, cooling the reaction kettle to room temperature, and filtering to obtain polyether;

C. heating a reaction container with polyether to 50-80 ℃, slowly adding benzotriazole or a derivative thereof into the container, heating and keeping the reaction temperature at 100-120 ℃, and reacting for 1-12 hours to obtain a compound 1 with hydroxyl at one end and benzotriazole in the main chain after the reaction is finished.

D. 40 to 50 parts of isocyanate compound is dissolved in 0.5 to 3 parts of diluent, the temperature is kept between 40 and 50 ℃, and the mixture is stirred for 20 to 40 minutes to prepare solution 1;

E. and (3) dropwise adding the solution 1 into 40-50 parts of the compound 1, heating to 50-90 ℃ after the dropwise adding, and aging for 1.5-2 hours to obtain the antioxidant.

In the method for preparing the antioxidant, preferably, the catalyst is a Zn-Co bimetallic catalyst or an alkaline catalyst.

Further, in the preparation method of the antioxidant, preferably, the diluent comprises a solvent A: the solvent B is prepared from (1-5) in a mass ratio of (10-20); the solvent A is selected from dichloromethane, chloroform and tetrachloromethane, and the solvent B is selected from tetrahydrofuran, furan, pyridine, pyrazine and pyrrole.

The antioxidant is prepared from raw materials such as chloralkylene oxide, benzotriazole derivatives, an initiator, a capping reagent and the like, and is prepared by modifying polyether to enable the polyether to have groups such as ether bond, amide bond, triazole and the like, so that the generation of free radicals and hydroperoxides can be prevented, oxidation reaction of compounds is prevented, and the antioxidant has better performance compared with the antioxidant in the prior art. Compared with the traditional antioxidant in lubricating oil, the antioxidant disclosed by the invention has good solubility in base oil and very excellent oxidation resistance.

Furthermore, the antioxidant has good detergency and rust resistance on the basis of good oxidation resistance.

In addition, the antioxidant can be adsorbed on the surface of metal, so that oxidation corrosion of the metal is prevented, and the antioxidant can be used as a metal passivating agent or a preservative.

The antioxidant disclosed by the invention is simple in preparation process, environment-friendly and easy to realize industrialization.

Detailed Description

Specific embodiments of the present invention will now be described in detail for a clearer understanding of the technical features, objects and effects of the present invention.

An antioxidant which is a compound of the following structure:

wherein m=0 to 100, n=0 to 100, and m and n are not zero at the same time; r is R ₁ Is C ₁ ～C ₁₅ Is an alkane of (a); r is R ₁ Preferably C ₁ ～C ₁₀ Is an alkane of (a).

R ₂ Is that

R ₃ Is->

Wherein R is ₄ Is hydrogen or C ₁ ～C ₄ R is any integer from 1 to 20; />

R is

Wherein R is ₅ Is hydrogen or C ₁ ～C ₂₀ Is an alkane of (a); r is R ₅ Preferably hydrogen or C ₁ ～C ₅ Is an alkane of (a). X is S or O; r is R ₆ 、R ₇ 、R ₈ Is hydrogen or C ₁ ～C ₅ Is an alkane of (a).

The preparation method of the antioxidant comprises the following steps:

A. the raw materials are selected as follows: 40-50 parts of chloralkylene oxide, catalyst and C ₁ ～C ₁₅ 40-50 parts of alkyl alcohol compounds, benzotriazole or derivatives thereof and 40-50 parts of isocyanate compounds; 0.5 to 3 parts of diluent, wherein the diluent comprises solvent A: the solvent B is selected from dichloromethane, trichloromethane and tetrachloromethane according to the mass ratio of (10-20) (1-5), and the solvent B is selected from tetrahydrofuran, furan, pyridine, pyrazine and pyrrole; the catalyst is selected from Zn-Co bimetallic catalysts or alkaline catalysts, for example: sodium hydroxide, potassium hydroxide, cesium hydroxide, calcium hydroxide.

Among the above raw materials, one kind of chloroalkylene oxide can be selected, two different kinds of chloroalkylene oxide can also be selected, the addition amount of the two kinds of chloroalkylene oxide and the proportion between the two kinds of chloroalkylene oxide can be determined according to different specific reaction requirements, required products, chain lengths and the like, wherein the first kind of chloroalkylene oxide is proportional to the use amount of the initiator: the molar ratio of initiator to the chloroalkylene oxide is (0.1:1) - (1:5). The amount of the second chloroalkylene oxide to be used depends on the values of m and n in the molecular chain of the final compound, i.e., the amount of the second chloroalkylene oxide to be used is determined according to the desired chain length, and the ratio of the two is not limited. That is, the total amount of the chloralkylene oxide is assumed to be constant, the dosage of each chloralkylene oxide is judged according to the chemical structure, that is, the dosage of each chloralkylene oxide finally determines the values of m and n, and the initiator and the total chloralkylene oxide are in a certain proportion relation.

B. Adding a catalyst into a dry reaction kettle with inert gas protection, wherein the addition amount of the catalyst is 20-100 ppm (mass ratio) of the prepared product, and then adding an initiator C ₁ ～C ₁₅ Wherein the molar ratio of the initiator to the chloroalkylene oxide is (0.1:1) - (1:5), heating the reaction kettle to 30-100 ℃, keeping the pressure below 1.5MPa, and when the temperature starts to rise and the pressure starts to fall, adopting two chloroalkylene oxides, and when the other chloroalkylene oxide is adopted, the other chloroalkylene oxide is used at 0.5-3 mL/minContinuously adding the mixture into a reaction kettle at a speed, continuously aging for 1-3 hours, stopping heating, cooling the reaction kettle to room temperature, and filtering to obtain polyether;

Specific examples are described in detail below.

Example 1, an antioxidant, is a compound of the structure:

the antioxidant is prepared by the following steps:

A. weighing the raw materials: chlorocyclohexane and chlorocyclopropane 40 parts (chlorocyclohexane: chlorocyclopropane molar ratio 1:6), bimetallic catalyst (Zn-Co bimetallic catalyst) 20ppm, methanol 0.1 part, benzotriazole 40 parts, and diluent 0.5 part, wherein the diluent is prepared from methylene dichloride: tetrahydrofuran in a mass ratio of 10:1, the composition is as follows; isocyanate compound

40 parts;

B. adding a catalyst into a dry reaction kettle with inert gas protection, adding an initiator methanol and chloroethylene, heating the reaction kettle to 30 ℃, keeping the pressure below 1.5MPa, when the temperature starts to rise and the pressure starts to fall, indicating that the reaction is started, continuously adding chlorocyclopropane into the reaction kettle at the rate of 0.5 mL/min, continuing aging for 1 hour, stopping heating, cooling the reaction kettle to room temperature, and filtering to obtain polyether;

C. heating a reaction container with polyether to 50 ℃, slowly adding benzotriazole into the container, heating and keeping the reaction temperature at 100 ℃, and reacting for 1 hour to obtain the compound 1 with hydroxyl at one end and benzotriazole in the main chain.

D. Dissolving an isocyanate compound in a diluent to form a solution 1, dropwise adding the solution 1 into a container containing the compound 1 at a rate of 0.1 mL/min at a temperature of 50 ℃, and continuously stirring for 20 minutes after the completion of dropwise adding;

E. the reaction vessel was heated to 60℃and aged for 1 hour to give the product of example 1.

The isocyanate Compound of this example is R in addition to the above raw materials ₅ Can also take hydrogen or C at will ₁ ～C ₂₀ The process for preparing the same as in this example is not repeated here.

Example 2, an antioxidant, is a compound of the structure:

the antioxidant is prepared by the following steps:

A. weighing the raw materials: 50 parts of chlorocyclohexane, 100ppm of bimetallic catalyst (Zn-Co bimetallic catalyst), 10 parts of n-hexanol and 50 parts of methylbenzotriazole (chlorocyclohexane: chlorocyclopropane molar ratio is 1:2); 1 part of a diluent, which consists of methylene dichloride: furan in mass ratio 10:3, composing; isocyanate compound

40 parts;

B. adding a catalyst into a dry reaction kettle with inert gas protection, and then adding an initiator n-hexylene alcohol and chlorocyclohexane, wherein the molar ratio of the initiator to the chlorocyclohexane is 0.1:1 to 1:5, heating the reaction kettle to 30-100 ℃, keeping the pressure below 1.5MPa, continuously adding chlorocyclopropane into the reaction kettle at the rate of 0.5-3 mL/min when the temperature starts to rise and the pressure starts to fall, continuously aging for 3 hours, stopping heating, cooling the reaction kettle to room temperature, and filtering to obtain polyether;

C. heating a reaction container with polyether to 80 ℃, slowly adding the methylbenzotriazole into the container, heating and keeping the reaction temperature at 120 ℃, and reacting for 12 hours to obtain the compound 1 with hydroxyl at one end and benzotriazole in the main chain.

D. Dissolving an isocyanate compound in a diluent to form a solution 1, dropwise adding the solution 1 into a container containing the compound 1 at a rate of 2 mL/min at a temperature of 60 ℃, and continuously stirring for 20 minutes after the completion of dropwise adding;

E. the reaction vessel was warmed to 90℃and aged for 2 hours to give the product of example 2.

Example 3, an antioxidant, is a compound of the structure:

the antioxidant is prepared by the following steps:

A. weighing the raw materials: 50 parts of chlorocyclohexane and chlorocyclopropane (the mol ratio of chlorocyclohexane to chlorocyclopropane is 100:71), 30ppm of potassium hydroxide catalyst, 1 part of n-hexanol and 50 parts of benzotriazole; 10 parts of isopropanol, 2 parts of a diluent, and the diluent is prepared from chloroform: furan in mass ratio 15:5 composition, isocyanate compound

40 parts;

B. adding a potassium hydroxide catalyst into a dry reaction kettle with inert gas protection, adding n-hexylene alcohol and chloroethylene, heating the reaction kettle to 50 ℃, keeping the pressure below 1.5MPa, when the temperature starts to rise and the pressure starts to fall, indicating that the reaction is started, continuously adding chlorocyclopropane into the reaction kettle at the rate of 2.5 mL/min, continuing aging for 3 hours, stopping heating, cooling the reaction kettle to room temperature, and filtering to obtain polyether;

C. heating a reaction container with polyether to 70 ℃, slowly adding benzotriazole into the container, heating and keeping the reaction temperature at 110 ℃, and reacting for 10 hours to obtain the compound 1 with hydroxyl at one end and benzotriazole in the main chain.

D. Dissolving an isocyanate compound in a diluent to form a solution 1, dropwise adding the solution 1 into a container containing the compound 1 at a rate of 1.5 mL/min at a temperature of 55 ℃, and continuously stirring for 30 minutes after the completion of dropwise adding;

E. the reaction vessel was warmed to 70℃and aged for 1.5 hours to give the product of example 3.

Example 4, an antioxidant, is a compound of the structure:

A. weighing the raw materials: 50 parts of chlorocyclohexane, 7 parts of nonyl-3-ol, 50 parts of benzotriazole, and the total of 50 parts of chlorocyclohexane and chlorocyclooctane (the molar ratio of chlorocyclohexane to chlorocyclopropane is 20:48); 3 parts of a diluent consisting of tetrachloromethane: pyridine is prepared from the following components in percentage by mass: 5 composition, isocyanate compound

40 parts;

B. adding a sodium hydroxide catalyst into a dry reaction kettle with inert gas protection, adding nonyl-3-alcohol and chlorocyclohexane, heating the reaction kettle to 60 ℃, keeping the pressure below 1.5MPa, when the temperature starts to rise and the pressure starts to fall, indicating that the reaction is started, continuously adding chlorocyclooctane into the reaction kettle at the rate of 1 mL/min, continuing aging for 1.5 hours, stopping heating, cooling the reaction kettle to room temperature, and filtering to obtain polyether;

C. heating a reaction container with polyether to 60 ℃, slowly adding benzotriazole into the container, heating and keeping the reaction temperature at 110 ℃, and reacting for 6 hours to obtain the compound 1 with hydroxyl at one end and benzotriazole in the main chain.

E. the reaction vessel was heated to 80℃and aged for 1 hour to give the product of example 4.

The isocyanate Compound of this example is R in addition to the above raw materials ₅ Can also take hydrogen or C at will ₁ ～C ₂₀ The process for preparing the alkanes of (a) to form novel compounds is the same as in this example and will not be described in detail herein

Example 5, an antioxidant, is a compound of the structure:

the antioxidant preparation procedure of this example is the same as in example 1, with the raw materials selected: 45 parts of chlorocyclohexane and chlorocyclopropane (mol ratio of chlorocyclohexane to chlorocyclopropane is 30:71), 60ppm of sodium hydroxide catalyst, 7 parts of decyl-4-alcohol, 45 parts of benzotriazole and 2 parts of diluent, wherein the diluent is prepared from tetrachloromethane: pyrazine in mass ratio of 20:3, composing; isocyanate compound

45 parts.

The isocyanate Compound of this example is R in addition to the above raw materials ₈ Can also take hydrogen or C at will ₁ ～C ₅ The process for preparing the alkanes of (a) to form novel compounds is the same as in this example and will not be described in detail herein

Example 6, an antioxidant, is a compound of the structure:

the antioxidant preparation procedure of this example is the same as in example 1, with the raw materials selected: 50 parts of chlorocyclododecane, 70ppm of Zn-Co bimetallic catalyst, 8 parts of n-hexadecanol and 50 parts of methylbenzotriazole; 1 part of a diluent, which consists of methylene dichloride: pyrrole in mass ratio of 20:1, isocyanate compound

50 parts.

Example 7, an antioxidant, is a compound of the structure:

the antioxidant preparation procedure of this example is the same as that of example 2, and the raw materials are selected: 50 parts of chlorocyclohexane, namely chlorocyclobehenate (chlorocyclohexane, namely chlorocyclobehenate, the mol ratio of which is 10:51), 100ppm of a bimetallic catalyst (Zn-Co bimetallic catalyst), 8 parts of n-heptanol and 50 parts of butylbenzotriazol; 1 part of a diluent, which consists of methylene dichloride: pyrrole in mass ratio of 20:1, isocyanate compound

50 parts.

The isocyanate Compound of this example is R in addition to the above raw materials ₅ Can also take hydrogen or C at will ₁ ～C ₂₀ The alkane of (2) may have a heteroatom to form a novel compound, and the preparation method is the same as that of the present example, and will not be described herein.

Example 8, an antioxidant, is a compound of the structure:

the antioxidant preparation procedure of this example is the same as that of example 3, and the raw materials are selected: 60 parts of chlorocyclohexane, 60 parts of chlorocycloheptane (molar ratio of chlorocyclohexane to chlorocycloheptane is 50:21), 60ppm of a bimetallic catalyst, 7 parts of isopropanol and 60 parts of ethylbenzotriazol; 2 parts of diluent (methylene dichloride: pyrrole in a mass ratio of 20:2), isocyanate compound

50 parts.

Example 9, an antioxidant, is a compound of the structure:

the antioxidant preparation procedure of this example is the same as that of example 3, and the raw materials are selected: 60 parts of chlorocyclohexane, namely chlorocycloundecane (mol ratio of chlorocyclohexane to chlorocycloundecane is 15:81), 60ppm of sodium hydroxide catalyst, 8 parts of heptyl-2-alcohol and 50 parts of methylbenzotriazole; 3 parts of diluent (chloroform: furan in a mass ratio of 20:6), isocyanate compound

60 parts.

Example 10, an antioxidant, is a compound of the structure:

the antioxidant preparation procedure of this example is the same as that of example 3, and the raw materials are selected: 60 parts of chlorocyclohexane, 1 part of decyl-3-alcohol and 60 parts of methylbenzotriazole, wherein the molar ratio of chlorocyclohexane to chlorocyclobutane is 5:26, and the catalyst of sodium hydroxide is 50 ppm; 0.5 part of diluent (tetrachloromethane: furan in a mass ratio of 15:6), isocyanate compound

60 parts. />

Example 11, an antioxidant, is a compound of the structure:

the antioxidant preparation procedure of this example is the same as that of example 3, and the raw materials are selected: 60 parts of chlorocyclohexane, namely chlorocycloundecane (mol ratio of chlorocyclohexane to chlorocycloundecane is 15:81), 60ppm of sodium hydroxide catalyst, 8 parts of heptyl-2-alcohol and 50 parts of methylbenzotriazole; diluent (chloroform: furan in mass ratio 20:6) 3Parts, isocyanate compound

60 parts.

Comparison experiment:

the existing common antioxidant is selected: zinc dialkyldithiophosphate (ZDDP), dialkyldithiocarbamate (ADTC), dialkyldithiophosphate (ADDP) as a comparative antioxidant.

1. Pressure differential calorimeter scan (PDSC) experiments; the determination is made according to ASTM D6186-1998 using the standard test method for measuring the oxidation induction time of lubricating oils by differential scanning calorimetry (PDSC). A sample of 3.0mg was used at a pressure of 3.5MPa and 210 ℃.

2. Rotary pressurized vessel oxidation experiment: the antioxidant property of the compound and the existing antioxidant is examined according to the measurement of the national standard ASTM D2272-2009 'method for measuring the oxidation stability of lubricating oil', and the longer the time is, the better the antioxidant effect is.

3. Copper corrosion experiment: the corrosion resistance of the compound and the existing antioxidant is examined according to GB 5096-2017 test method for corrosion test of liquefied Petroleum gas copper sheets. The smaller the number of the copper corrosion test result is, the better the corrosion resistance is represented.

4. Detergency test: the results were measured according to SH/T0269-1992, method for determining detergency of lubricating oil for internal Combustion Engine, and were classified into seven classes from No. 0 to No. 6. No. 0 is cleanest, the color is lightest, no. 6 is dirtiest, the color is darkest, the smaller the number is, and the better the detergency is.

Detection result

As can be seen from the table, the antioxidant of the compound of the present invention is superior to the conventional antioxidant, and the antioxidant of the present invention has excellent antioxidant effect. Meanwhile, the paint has better corrosion resistance and cleaning performance.

Claims

1. An antioxidant, characterized by being a compound of the structure:

wherein m=0 to 100, n=0 to 100, and m and n are not zero at the same time;

R ₁ is C ₁ ～C ₁₅ Alkyl of (a);

R ₂ is that

R ₃ Is->

Wherein R is ₄ Is hydrogen or C ₁ ～C ₄ R is an integer of 1 to 20;

r is

Or a combination thereof; wherein R is ₅ Is hydrogen or C ₁ ～C ₂₀ Alkyl of (a); x is S or O; r is R ₆ 、R ₇ 、R ₈ Is hydrogen or C ₁ ～C ₅ Is a hydrocarbon group.

2. The antioxidant of claim 1, wherein R is ₁ Selected from C ₁ ～C ₁₀ Is a hydrocarbon group.

3. The antioxidant of claim 1, wherein R is ₂ Is benzotriazole or its derivative

Wherein R is ₄ Selected from C ₁ ～C ₂ Is a hydrocarbon group.

4. The antioxidant of claim 1, wherein R is ₃ Is benzotriazole or its derivative

Wherein R is ₄ Selected from C ₁ ～C ₂ R is an integer of 1 to 10.

5. The antioxidant of claim 1, wherein R is ₅ Selected from hydrogen or C ₁ ～C ₅ Is a hydrocarbon group.

6. The antioxidant of claim 1, wherein R is selected from the group consisting of

7. The preparation method of the antioxidant is characterized by comprising the following steps of:

A. the raw materials are selected as follows: 40-50 parts of chloralkylene oxide, catalyst and C ₁ ～C ₁₅ Alkyl alcohol compound, benzotriazole and derivative thereof

Wherein R is ₄ Selected from C ₁ ～C ₂ 40 to 50 parts of alkyl, r is any integer from 1 to 10, and 40 to 50 parts of isocyanate compound; 0.5-3 parts of diluent;

B. adding a catalyst into a dry reaction kettle with inert gas protection, wherein the adding amount of the catalyst is 20-100 ppm of the prepared product by weight, and then adding an initiator C ₁ ～C ₁₅ The molar ratio of the initiator to the chloroalkylene oxide is (0.1:1) - (1:5), the reaction kettle is heated to 30-100 ℃, the pressure is kept to be less than 1.5MPa, when the temperature starts to rise and the pressure starts to fall, when two chloroalkylene oxides are adopted, the other chloroalkylene oxide is continuously added into the reaction kettle at the rate of 0.5-3 mL/min, the aging is continued for 1-3 hours, the heating is stopped, the reaction kettle is cooled to room temperature, and the polyether is obtained after filtration;

C. heating the reaction vessel with polyether to 50-80 ℃, and slowly adding benzotriazole and its derivative into the vessel

Wherein R is ₄ Selected from C ₁ ～C ₂ The alkyl of (2) is an arbitrary integer of 1-10, the temperature is raised and kept at 100-120 ℃, the reaction is carried out for 1-12 hours, and the compound 1 with hydroxyl at one end and benzotriazole in the main chain is obtained after the reaction is finished;

8. The method for producing an antioxidant according to claim 7, wherein the catalyst is a Zn-Co type bimetallic catalyst or an alkaline catalyst.

9. The method for preparing the antioxidant according to claim 7, wherein the diluent comprises solvent a: the solvent B is prepared from (1-5) in a mass ratio of (10-20); the solvent A is selected from dichloromethane, chloroform and tetrachloromethane, and the solvent B is selected from tetrahydrofuran, furan, pyridine, pyrazine and pyrrole.