Phenolic anti-aging styrene-butadiene rubber and preparation method thereof

Abstract

The invention discloses phenolic anti-aging styrene-butadiene rubber and a preparation method thereof, and relates to the technical field of rubber functional modification.The preparation method of the phenolic anti-aging styrene-butadiene rubber comprises the steps that firstly, epoxidation reaction is conducted on styrene-butadiene rubber through metachloroperbenzoic acid, then epoxy group ring-opening reaction is conducted on the styrene-butadiene rubber and hydrochloric acid, and the phenolic anti-aging styrene-butadiene rubber is obtained. And finally, carrying out esterification reaction with a phenolic anti-aging agent to prepare the phenolic anti-aging styrene-butadiene rubber. According to the invention, a phenol-containing anti-aging functional side chain is grafted in a styrene-butadiene rubber molecular chain through an epoxy-ring opening-esterification three-step reaction, so that the thermal oxidation resistance and ozone aging resistance of the styrene-butadiene rubber are improved, and meanwhile, the problem that a micromolecular anti-aging agent is easy to migrate in a rubber matrix due to relatively poor compatibility is solved.

Description

Technical Field

[0001] The invention relates to the technical field of rubber functional modification, and more particularly to a phenolic anti-aging styrene-butadiene rubber and a preparation method thereof. Background Art

[0002] Commonly used rubber materials, such as natural rubber (NR), styrene-butadiene rubber (SBR), butadiene rubber (BR), nitrile rubber (NBR) and other diene rubbers, are prone to aging under conditions such as oxygen, ozone, light, and heat due to the large number of isolated unsaturated carbon-carbon double bonds and active allylic hydrogen structures on the main chain. Thermal oxygen aging and ozone aging, as the most common types of rubber aging, can significantly damage the physical or chemical properties of rubber materials, causing rubber products to fail prematurely, which not only causes a waste of precious rubber resources, but also seriously threatens people's life safety. Adding antioxidants to the rubber matrix is ​​the most convenient and effective method to inhibit the aging of rubber materials. However, these antioxidants are usually easy to migrate out of the rubber matrix under low pressure, liquid, high temperature and other use conditions due to their low molecular weight, thereby reducing the protective effect of the antioxidant. In addition, the migrated antioxidants will cause surface defects of rubber products, and may even have toxic effects on the environment and even the human body.

[0003] At present, amine antioxidants, especially p-phenylenediamine antioxidants, are widely used in various rubber products due to their good comprehensive protective effect, wide variety and low price. Although p-phenylenediamine antioxidants have excellent resistance to thermal oxidation and ozone aging, they are low in safety, highly harmful and easy to dye. The EU has listed them as restricted compounds. Studies have shown that 6PPD-quinone substances, the transformation product of p-phenylenediamine antioxidant 6PPD in tire wear particles, are chemicals that cause urban silver salmon runoff mortality syndrome. These substances have adverse effects on environmental protection and human health. Compared with amine antioxidants, phenolic antioxidants are more applicable in polymer materials due to their non-discoloration and non-polluting characteristics, but their comprehensive protective effect is not as good as that of amine antioxidants, which limits the application of phenolic antioxidants. Summary of the invention

[0004] In order to solve the problems existing in the prior art, the present invention provides a phenolic anti-aging styrene-butadiene rubber and a preparation method thereof. The present invention grafts a phenolic anti-aging functionalized side chain into the styrene-butadiene rubber molecular chain through a three-step reaction of epoxy-ring opening-esterification to improve the heat oxygen and ozone aging resistance of the styrene-butadiene rubber, and at the same time solves the problem that small molecule antioxidants are easy to migrate in the rubber matrix due to poor compatibility.

[0005] One of the objects of the present invention is to provide a phenolic anti-aging styrene-butadiene rubber, wherein the phenolic anti-aging styrene-butadiene rubber has the structural formula:

[0006]

[0007] Wherein, a, b, c, d, e, f correspond to the molar content percentage of each repeating unit in the phenolic anti-aging styrene-butadiene rubber, and its value depends on the molecular chain structure of the selected styrene-butadiene rubber, a: 15-35 mol%, b: 40-80 mol%, c: 5-35 mol%, d: 0.5-10 mol%, e: 0.5-10 mol%, f: 0.5-10 mol%, preferably a: 20-30 mol%; b: 30-45 mol%; c: 10-20 mol%; d: 1-5 mol%; e: 1-5 mol%; f: 1-5 mol%;

[0008] The phenolic side chain content (ie the molar percentage of the repeating unit f) of the phenolic anti-aging styrene-butadiene rubber is 0.5 to 10 mol %, preferably 1 to 5 mol %.

[0009] A second object of the present invention is to provide a method for preparing a phenolic anti-aging styrene-butadiene rubber, the method comprising:

[0010] Firstly, epoxidation reaction is carried out on styrene butadiene rubber by using meta-chloroperoxybenzoic acid, then epoxy ring-opening reaction is carried out with hydrochloric acid, and finally esterification reaction is carried out with a phenolic antioxidant to prepare the phenolic anti-aging styrene butadiene rubber.

[0011] Preferably,

[0012] The method comprises:

[0013] (1) adding a m-chloroperbenzoic acid solution dropwise into a styrene-butadiene rubber solution to carry out an epoxidation reaction, and after the reaction is completed, post-treating to obtain an epoxidized styrene-butadiene rubber;

[0014] (2) adding a hydrochloric acid solution dropwise to a solution of the epoxidized styrene butadiene rubber dissolved in solvent A to carry out an epoxy ring-opening reaction, and after the reaction is completed, post-treating to obtain a hydroxylated styrene butadiene rubber;

[0015] (3) adding a phenolic antioxidant and an acylation catalyst to a solution of the hydroxylated styrene butadiene rubber dissolved in solvent B for activation reaction, then adding a di-electron affinity condensing agent for esterification reaction, and after the reaction is completed, post-treating to obtain the phenolic anti-aging styrene butadiene rubber.

[0016] Preferably,

[0017] In step (1):

[0018] The styrene butadiene rubber is a styrene butadiene rubber commonly used in the art, including but not limited to SBR1502;

[0019] The solvent of the meta-chloroperbenzoic acid solution is tetrahydrofuran, which is a polar solvent that can dissolve meta-chloroperbenzoic acid and can be miscible with the solvent that dissolves styrene-butadiene rubber to form a homogeneous reaction system; and / or,

[0020] The solvent of the styrene-butadiene rubber solution is at least one of cyclohexane, toluene, xylene, tetrahydrofuran, n-hexane and dichloromethane.

[0021] Preferably,

[0022] In step (1):

[0023] The concentration of the meta-chloroperbenzoic acid solution is 20wt% to 50wt%; and / or,

[0024] The concentration of the styrene-butadiene rubber solution is 5wt% to 15wt%; and / or,

[0025] The molar ratio of the meta-chloroperbenzoic acid to the carbon-carbon double bonds in the styrene-butadiene rubber is (0.10-0.20):1, preferably (0.12-0.15):1.

[0026] Preferably,

[0027] In step (1):

[0028] The epoxidation reaction is carried out at a temperature of 25°C to 45°C and for a time of 1 to 4 hours; and / or,

[0029] The post-processing includes:

[0030] Adding alkaline solution to the reaction solution to adjust the pH value to 7-8, flocculating in a flocculant, and drying to obtain the epoxidized styrene-butadiene rubber;

[0031] Preferably,

[0032] The alkali solution is at least one of sodium hydroxide solution, sodium bicarbonate solution and ammonia water; and / or,

[0033] The flocculant is at least one of anhydrous ethanol and anhydrous methanol.

[0034] Preferably,

[0035] In step (2):

[0036] The solvent A is at least one of tetrahydrofuran, toluene, xylene and dichloromethane; and / or,

[0037] The concentration of the hydrochloric acid solution is 20wt% to 36.5wt%; and / or,

[0038] The concentration of the epoxidized styrene-butadiene rubber dissolved in solvent A is 5wt% to 15wt%; and / or,

[0039] The molar ratio of the hydrochloric acid to the epoxy group in the epoxidized styrene-butadiene rubber is (0.5-3):1, preferably (1-1.5):1.

[0040] Preferably,

[0041] In step (2):

[0042] The temperature of the epoxy ring-opening reaction is 15°C to 35°C and the time is 2 to 4 hours; and / or,

[0043] The post-processing includes:

[0044] After flocculating the reaction solution in a flocculant, drying is performed to obtain the hydroxylated styrene-butadiene rubber;

[0045] Preferably,

[0046] The flocculant is at least one of anhydrous ethanol and anhydrous methanol.

[0047] Preferably,

[0048] In step (3):

[0049] The solvent B is at least one of dichloromethane, chloroform, ether, carbon tetrachloride and toluene; and / or,

[0050] The concentration of the solution of the hydroxylated styrene-butadiene rubber dissolved in the solvent B is 5 to 15 wt %; and / or,

[0051] The phenolic antioxidant is a phenolic antioxidant containing a carboxyl group;

[0052] Preferably,

[0053] The carboxyl-containing phenolic antioxidant is at least one of 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid, 3,5-di-tert-butyl-4-hydroxybenzoic acid, 3,5-di-tert-butyl-4-hydroxyphenylacetic acid, 3,5-di-tert-butyl salicylic acid, and 3,4,5-trihydroxybenzoic acid (gallic acid); and / or

[0054] The molar ratio of the phenolic antioxidant to the hydroxyl group in the hydroxylated styrene-butadiene rubber is (1-3):1, preferably (1.2-1.5):1; and / or,

[0055] The acylation catalyst is at least one of 4-dimethylaminopyridine (DMAP), 4-pyrrolidinylpyridine (4-PPY), 1-hydroxybenzotriazole, and N-hydroxy-7-azabenzotriazole. The unstable intermediate generated during the activation reaction can be converted into the corresponding active ester or active amide by the acylation catalyst to prevent itself from forming urea; and / or,

[0056] The molar ratio of the acylation catalyst to the hydroxyl group in the hydroxylated styrene-butadiene rubber is (0.2-1):1, preferably (0.4-0.6):1; and / or,

[0057] The di-electron affinity condensing agent is a carbodiimide condensing agent;

[0058] Preferably,

[0059] The carbodiimide condensing agent is at least one of 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDCI), dicyclohexylcarbodiimide, and diisopropylcarbodiimide, which forms an amide or acyl ion intermediate with carboxylic acid, and the intermediate can undergo an acylation reaction; and / or,

[0060] The molar ratio of the di-electron affinity condensing agent to the hydroxyl group in the hydroxylated styrene-butadiene rubber is (1-3):1, preferably (1.5-1.8):1.

[0061] Preferably,

[0062] In step (3):

[0063] The activation reaction time is 1 to 4 hours, and the temperature is 20° C. to 35° C.; and / or,

[0064] The esterification reaction time is 12 to 48 hours, and the temperature is 20° C. to 35° C.; and / or,

[0065] During the esterification reaction, a protective gas is introduced;

[0066] Preferably,

[0067] The protective gas is at least one of nitrogen and inert gas;

[0068] More preferably,

[0069] The inert gas is argon, which can prevent the rubber and reagents from being oxidized during the reaction; and / or,

[0070] The post-processing includes:

[0071] After the reaction solution is co-precipitated in solvent C, it is washed and dried to obtain the phenolic anti-aging styrene-butadiene rubber;

[0072] Preferably,

[0073] The solvent C is at least one of ethanol and methanol.

[0074] The following solutions can be adopted:

[0075] It includes three steps: epoxidation-ring opening-esterification:

[0076] (1) Add styrene butadiene rubber to a three-necked flask filled with a solvent and stir at a certain speed until it is completely dissolved, and the concentration of the rubber solution is 5wt% to 15wt%; then, dissolve meta-chloroperoxybenzoic acid (m-CPBA) in tetrahydrofuran, and add it to a constant pressure dropping funnel for use after it is completely dissolved; the reaction temperature is 25°C to 45°C, open the constant pressure dropping funnel, slowly add the m-CPBA solution, and react for 1 to 4 hours; after the reaction is completed, add an alkaline solution to wash until the pH is 7 to 8, then flocculate the product in a flocculant, and dissolve it in THF and flocculate it, repeating three times to remove the generated meta-chlorobenzoic acid; finally, dry the obtained product in a 60°C forced air drying oven to constant weight to obtain epoxidized styrene butadiene rubber (e-ESBR);

[0077] (2) adding the product e-ESBR obtained in step (1) into a three-necked flask filled with tetrahydrofuran, stirring at a speed of 200 r / min until completely dissolved, and the concentration of the rubber solution is 5wt% to 15wt%; then, adding a certain amount of HCl solution dropwise into the three-necked flask, and reacting at 15°C to 35°C for 2 to 4h; after the reaction, flocculating the product in a flocculant, and dissolving it in THF and then flocculating, repeating the process three times to remove excess HCl; finally, drying the obtained product in a blast drying oven at 40°C to constant weight, to obtain hydroxylated styrene butadiene rubber (HO-ESBR);

[0078] (3) The product HO-ESBR obtained in step (2) is dissolved in a dried solvent B, and then a phenolic antioxidant and an acylation catalyst are added to the solution and stirred for activation for 1 to 4 hours. Then, a di-electron affinity condensing agent is added to the mixed solution, and a protective gas is introduced under stirring at room temperature. After reacting for 24 to 48 hours, the rubber solution is co-precipitated in an excess of solvent C, washed, and dried in a forced air oven at 55° C. to obtain a phenolic anti-aging styrene-butadiene rubber (ESBR-g-BHTA).

[0079] Because styrene-butadiene rubber is prone to aging under conditions such as oxygen, ozone, light, heat, etc., its aging resistance is often improved by the method of adding antioxidant, the commonly used antioxidant of styrene-butadiene rubber is a small molecule p-phenylenediamine antioxidant such as antioxidant 4010, antioxidant 4020, etc., which has poor compatibility with rubber, and under low pressure, liquid, high temperature and other conditions of use, it is easy to migrate out from the rubber matrix, thereby reducing the protective effect of the antioxidant. Secondly, p-phenylenediamine antioxidant and its aging product have biological toxicity, which can produce toxic effects on the environment and human body. The protective effect of phenolic antioxidant is poor, and the protective effect often cannot reach the required protective effect within a certain dosage range, which limits the application of phenolic antioxidant in rubber.

[0080] The present invention improves the aging resistance of styrene-butadiene rubber by introducing phenolic functionalized side chains on the styrene-butadiene rubber molecular chain, and solves the problem that small molecule antioxidants are easily migrated out in the rubber matrix due to poor compatibility. Since the phenolic antioxidants cannot directly react with the styrene-butadiene rubber, the present invention first epoxidizes the styrene-butadiene rubber with meta-chloroperbenzoic acid to introduce high-activity reaction sites of epoxy groups into the rubber molecular chain, and then ring-opens the epoxy groups with hydrochloric acid, successfully introducing hydroxyl groups that can react with the phenolic antioxidants on the molecular chain, and finally successfully synthesizes the phenolic anti-aging styrene-butadiene rubber through the esterification reaction of hydroxyl groups and carboxyl groups, which has good thermal oxygen and ozone aging resistance, and solves the problems that styrene-butadiene rubber is easy to age during storage and use, small molecule antioxidants are easy to migrate in the rubber matrix, and the protective effect of phenolic antioxidants is not good. BRIEF DESCRIPTION OF THE DRAWINGS

[0081] Figure 1 The H NMR spectra of commercially available styrene butadiene rubber 1502, the epoxidized styrene butadiene rubber and the hydroxylated styrene butadiene rubber prepared in Example 1, and the phenolic anti-aging styrene butadiene rubber prepared in Examples 1, 7, 26, 27, and 29;

[0082] As can be seen from the figure, the characteristic signal peaks representing the trans and cis epoxy group methine protons appear at 2.98~2.92ppm and 2.75~2.63ppm, respectively, indicating that the epoxidized emulsion polybutadiene rubber is successfully synthesized; after the epoxidized styrene butadiene rubber is opened with HCl, the peak of the epoxy group disappears completely, 3.97 and 3.89ppm correspond to the proton absorption peaks connected to the carbon on Cl, and 3.72 and 3.61ppm correspond to the proton absorption peaks connected to the carbon on OH. After the ring opening, since the polybutadiene unit in the epoxidized styrene butadiene rubber has both cis and trans structures, there are two peaks representing the OH structure, one high and one low. This is because the polarity of the cis and trans structures is different, the coupling constants are different, and therefore the chemical shifts are different, indicating that the hydroxylated styrene butadiene rubber is successfully synthesized; through the activation reaction and esterification reaction to graft phenolic antioxidants, 7.04ppm, 5.12 The proton peaks on the benzene ring of 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid, the phenolic hydroxyl proton peak, the methylene proton peak and the methyl proton peak appeared at 2.92ppm, 2.69ppm and 1.47ppm, respectively. In addition, there were proton absorption peaks on the carbon connected to the chlorine atom at 3.95ppm and 3.85ppm, and proton absorption peaks on the remaining hydroxyl carbon at 3.72ppm and 3.62ppm, respectively, proving that the phenolic anti-aging styrene-butadiene rubber was successfully synthesized, and with the increase of the amount of phenolic anti-aging functional side chains, the peak intensities of the proton peaks on the benzene ring of 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid, the phenolic hydroxyl proton peak, the methylene proton peak and the methyl proton peak increased at 7.04ppm, 5.12ppm, 2.92ppm, 2.69ppm and 1.47ppm, respectively.

[0083] Figure 2 The cracking conditions of the phenolic anti-aging styrene-butadiene rubber prepared in Example 1, Example 7 and Example 18, the commercial styrene-butadiene rubber 1502 in Comparative Example 1, and the styrene-butadiene rubber added with the commercial antioxidant BHT in Comparative Example 2 after ozone aging for 72 hours in a static tensile test;

[0084] The phenolic anti-aging styrene-butadiene rubber prepared in Example 1, Example 7 and Example 18, the commercial styrene-butadiene rubber 1502 in Comparative Example 1, and the styrene-butadiene rubber added with commercial antioxidant BHT in Comparative Example 2 were ozone aged for 72 hours, and then tested for ozone cracking resistance static tensile test according to GB / T7762-1987;

[0085] from Figure 2 It can be seen that the phenolic anti-aging styrene-butadiene rubber prepared in Example 1, Example 7 and Example 18 only showed fine cracks but no breakage, while the commercially available styrene-butadiene rubber 1502 (Comparison 1) and the styrene-butadiene rubber with added commercial antioxidant BHT (Comparison Example 2) showed large cracks and breakage, indicating that the phenolic anti-aging styrene-butadiene rubber of the present invention has good ozone aging resistance. DETAILED DESCRIPTION

[0086] The present invention is described in detail below in conjunction with specific drawings and embodiments. It is necessary to point out that the following embodiments are only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made to the present invention by those skilled in the art based on the content of the present invention still fall within the scope of protection of the present invention.

[0087] The raw materials used in the examples of the present invention are all commercially available products, and their specific information is shown in Table 1:

[0088] Table 1

[0089]

[0090] Example 1

[0091] (1) 100g of styrene butadiene rubber 1502 (the butadiene content of styrene butadiene rubber 1502 is 76.5%) is added to a three-necked flask filled with cyclohexane and stirred at a certain speed until it is completely dissolved. The concentration of the rubber solution is 10wt%. Then, 34.5g of m-chloroperoxybenzoic acid (m-CPBA) (purity is 85%) (the molar ratio of m-CPBA to carbon-carbon double bonds in styrene butadiene rubber is 0.12:1) is dissolved in tetrahydrofuran at a concentration of 35wt%. After it is completely dissolved, it is added to a constant pressure dropping funnel for use. The styrene butadiene rubber solution is raised to 35°C, the constant pressure dropping funnel is opened, and the m-CPBA solution is slowly added and reacted for 1h. After the reaction is completed, 10% NaOH solution is added to wash until the pH is 7-8, and then the product is flocculated in anhydrous ethanol and dissolved in THF and flocculated. This is repeated three times to remove the generated m-chlorobenzoic acid. Finally, the obtained product was dried in a blast drying oven at 60° C. to constant weight to obtain epoxidized styrene-butadiene rubber e-ESBR with an epoxidation degree of 10% (epoxidation degree = (A 2.98-2.85 +A 2.77-2.64 ) / (A 5.50-5.10 +A 5.07-4.78 +A 2.77-2.64 +A 2.98-2.85 )×100%, the epoxy degree is based on the integral area A of the epoxy group in the H-NMR spectrum 2.98-2.85 (trans structure) and A 2.77-2.64 (cis structure); double bond integrated area A 5.50-5.10 (1,4 addition) and A 5.07-4.78 (1,2 addition) calculated).

[0092] (2) Add 100g of the above-obtained product, epoxidized styrene butadiene rubber e-ESBR (the content of epoxy groups in e-ESBR is 109mmol), into a three-necked flask filled with tetrahydrofuran and stir at a speed of 200r / min until completely dissolved. The concentration of the rubber solution is 10wt%. Then, 10.9g of 36.5% HCl solution (the molar ratio of HCl to epoxy groups in epoxidized styrene butadiene rubber is 1:1) is added dropwise into the three-necked flask and reacted at 35°C for 2h. After the reaction is completed, the product is flocculated in anhydrous ethanol and dissolved in THF and then flocculated. This process is repeated three times to remove excess HCl. Finally, the obtained product is dried in a 40°C forced air drying oven to constant weight to obtain hydroxylated styrene butadiene rubber HO-ESBR. The degree of hydroxylation is 6% (degree of hydroxylation = double bond content × epoxy degree × ring opening rate, where ring opening rate = A 3.70-3.50 / [A 3.70-3.50 +(A 2.98-2.85 +A 2.77-2.64 ) / 2]×100%, the ring opening rate is based on the integral area A of the hydroxyl structure repeating unit in the H NMR spectrum 3.70-3.50 , the integral area of ​​the epoxy structure repeating unit A 2.98-2.85 and A2.77-2.64 Calculation shows that the ring opening rate is 80% and the double bond content in styrene-butadiene rubber 1502 is 76.5 wt%).

[0093] (3) 100 g of the product HO-ESBR (the hydroxyl group in HO-ESBR is 56 mmol) was dissolved in dried dichloromethane to a concentration of 10 wt %, and then 19.4 g of 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid (BHTA) (the molar ratio of 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid to the hydroxyl group in the hydroxylated styrene-butadiene rubber is 1.2:1) and 3.4 g of 4-dimethylaminopyridine (DMAP) (the molar ratio of 4-dimethylaminopyridine to the hydroxyl group in the hydroxylated styrene-butadiene rubber is 0.5:1) were added to the solution and stirred for activation for 1 h. Then 16.5 g of DMAP was added to the mixed solution. 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDCI) (the molar ratio of 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride to the hydroxyl group in the hydroxylated styrene-butadiene rubber is 1.5:1) is subjected to esterification reaction, and nitrogen is introduced under stirring at room temperature. After reacting for 24 hours, the rubber solution is co-precipitated in excess ethanol, washed, and dried in a forced air oven at 55°C to obtain a phenolic anti-aging styrene-butadiene rubber (structural formula is as follows).

[0094]

[0095] By using the integral area calculation of the corresponding structure in the H-NMR spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 57 mol%, 12 mol%, 1.5 mol%, 4.8 mol%, and 1.2 mol%, respectively, that is, the content of phenolic side chains was 1.2 mol%.

[0096] Example 2

[0097] The preparation method is basically the same as that of Example 1, except that in step (1), the solvent type and the concentration of the styrene-butadiene rubber solution in the epoxidation reaction are n-hexane and the concentration of the styrene-butadiene rubber solution is 15 wt %.

[0098] By using the integral area calculation of the corresponding structure in the H-NMR spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 58 mol%, 12 mol%, 1.4 mol%, 4.0 mol%, and 1.1 mol%, respectively, that is, the content of phenolic side chains was 1.1 mol%.

[0099] Example 3

[0100] The preparation method is basically the same as that of Example 1, except that in step (1), the solvent type and the concentration of the styrene-butadiene rubber solution in the epoxidation reaction are xylene and the concentration of the styrene-butadiene rubber solution is 5 wt %.

[0101] By using the integral area calculation of the corresponding structure in the H-NMR spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 57 mol%, 12 mol%, 1.5 mol%, 4.8 mol%, and 1.2 mol%, respectively, that is, the content of phenolic side chains was 1.2 mol%.

[0102] Example 4

[0103] The preparation method is basically the same as that of Example 1, except that the reaction time and reaction temperature of the epoxidation reaction in step (1) are 2 h and 45 °C.

[0104] By using the integral area calculation of the corresponding structure in the H-NMR spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 57 mol%, 12 mol%, 1.5 mol%, 4.8 mol%, and 1.2 mol%, respectively, that is, the content of phenolic side chains was 1.2 mol%.

[0105] Example 5

[0106] The preparation method is basically the same as that of Example 1, except that the reaction time and reaction temperature of the epoxidation reaction in step (1) are 4 h and 25 °C.

[0107] By using the integral area calculation of the corresponding structure in the H-NMR spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 57 mol%, 12 mol%, 1.5 mol%, 4.8 mol%, and 1.2 mol%, respectively, that is, the content of phenolic side chains was 1.2 mol%.

[0108] Example 6

[0109] The preparation method is basically the same as that of Example 1, except that the amount of m-chloroperbenzoic acid used in the epoxidation reaction in step (1) is 28.8 g, that is, the molar ratio of m-chloroperbenzoic acid to the carbon-carbon double bond in styrene-butadiene rubber is 0.10:1.

[0110] By using the integral area calculation of the corresponding structure in the hydrogen nuclear magnetic spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 59 mol%, 12 mol%, 1.0 mol%, 3.5 mol%, and 1.0 mol%, respectively, that is, the phenolic side chain content was 1.0 mol%.

[0111] Example 7

[0112] The preparation method is basically the same as that of Example 1, except that the amount of m-chloroperbenzoic acid used in the epoxidation reaction in step (1) is 57.5 g, that is, the molar ratio of m-chloroperbenzoic acid to the carbon-carbon double bond in styrene-butadiene rubber is 0.20:1.

[0113] By using the integral area calculation of the corresponding structure in the hydrogen nuclear magnetic spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 50 mol%, 12 mol%, 3.1 mol%, 9.2 mol%, and 2.2 mol%, respectively, that is, the content of phenolic side chains was 2.2 mol%.

[0114] Example 8

[0115] The preparation method is basically the same as that of Example 1, except that the amount of hydrochloric acid used in the epoxy ring-opening reaction in step (2) is 5.5 g, and the molar ratio of hydrochloric acid to epoxy is 0.5:1.

[0116] By using the integral area calculation of the corresponding structure in the hydrogen nuclear magnetic spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 57 mol%, 12 mol%, 2.7 mol%, 3.8 mol%, and 1.0 mol%, respectively, that is, the phenolic side chain content was 1.0 mol%.

[0117] Example 9

[0118] The preparation method is basically the same as that of Example 1, except that the amount of hydrochloric acid used in the epoxy ring-opening reaction in step (2) is 32.7 g, that is, the molar ratio of hydrochloric acid to epoxy is 3:1.

[0119] By using the integral area calculation of the corresponding structure in the hydrogen nuclear magnetic spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 57 mol%, 12 mol%, 0.8 mol%, 4.9 mol%, and 1.8 mol%, respectively, that is, the content of phenolic side chains was 1.8 mol%.

[0120] Example 10

[0121] The preparation method is basically the same as that of Example 1, except that the concentration of hydrochloric acid used in the epoxy ring-opening reaction in step (2) is 20%, and the amount used is 19.9 g, that is, the molar ratio of hydrochloric acid to epoxy is 1:1.

[0122] By using the integral area calculation of the corresponding structure in the hydrogen nuclear magnetic spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 57 mol%, 12 mol%, 2.7 mol%, 3.8 mol%, and 1.0 mol%, respectively, that is, the phenolic side chain content was 1.0 mol%.

[0123] Embodiment 11

[0124] The preparation method is basically the same as that of Example 1, except that the concentration of hydrochloric acid used in the epoxy ring-opening reaction in step (2) is 30%, and the amount used is 13.3 g, that is, the molar ratio of hydrochloric acid to epoxy is 1:1.

[0125] By using the integral area calculation of the corresponding structure in the hydrogen nuclear magnetic spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 57 mol%, 12 mol%, 2.4 mol%, 4.0 mol%, and 1.1 mol%, respectively, that is, the content of phenolic side chains was 1.1 mol%.

[0126] Example 12

[0127] The preparation method is basically the same as that of Example 1, except that the solvent A and the concentration of the glue used in the epoxy ring-opening reaction in step (2) are toluene and 5 wt % of the glue.

[0128] By using the integral area calculation of the corresponding structure in the H-NMR spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 57 mol%, 12 mol%, 2.0 mol%, 4.5 mol%, and 1.0 mol%, respectively, that is, the phenolic side chain content was 1.0 mol%.

[0129] Embodiment 13

[0130] The preparation method is basically the same as that of Example 1, except that the solvent A and the concentration of the glue used in the epoxy ring-opening reaction in step (2) are dichloromethane and the concentration of the glue is 15 wt %.

[0131] By using the integral area calculation of the corresponding structure in the hydrogen nuclear magnetic spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 57 mol%, 12 mol%, 2.2 mol%, 4.2 mol%, and 1.1 mol%, respectively, that is, the phenolic side chain content was 1.0 mol%.

[0132] Embodiment 14

[0133] The preparation method is basically the same as that of Example 1, except that the reaction time and reaction temperature of the epoxy ring-opening reaction in step (2) are 3 h and 35 °C.

[0134] By using the integral area calculation of the corresponding structure in the H-NMR spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 57 mol%, 12 mol%, 1.5 mol%, 4.8 mol%, and 1.2 mol%, respectively, that is, the content of phenolic side chains was 1.2 mol%.

[0135] Embodiment 15

[0136] The preparation method is basically the same as that of Example 1, except that the reaction time and reaction temperature of the epoxy ring-opening reaction in step (2) are 4 h and 15 °C.

[0137] By using the integral area calculation of the corresponding structure in the H-NMR spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 57 mol%, 12 mol%, 1.4 mol%, 4.8 mol%, and 1.3 mol%, respectively, that is, the content of phenolic side chains was 1.3 mol%.

[0138] Example 16

[0139] The preparation method is basically the same as that of Example 1, except for the type of solvent B and the concentration of the glue solution used in the activation reaction in step (3). Solvent B is chloroform and the concentration of the glue solution is 15 wt %.

[0140] By using the integral area calculation of the corresponding structure in the H-NMR spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 57 mol%, 12 mol%, 1.5 mol%, 4.8 mol%, and 1.2 mol%, respectively, that is, the content of phenolic side chains was 1.2 mol%.

[0141] Embodiment 17

[0142] The preparation method is basically the same as that of Example 1, except for the type of solvent B and the concentration of the glue solution used in the activation reaction in step (3). Solvent B is toluene and the concentration of the glue solution is 5 wt %.

[0143] By using the integral area calculation of the corresponding structure in the H-NMR spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 57 mol%, 12 mol%, 1.5 mol%, 4.9 mol%, and 1.1 mol%, respectively, that is, the content of phenolic side chains was 1.1 mol%.

[0144] Embodiment 18

[0145] The preparation method is basically the same as that of Example 1, except that the amount of the phenolic antioxidant 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid (BHTA) used in the esterification reaction in step (3) is 16.2 g, that is, the molar ratio of the phenolic antioxidant to the hydroxyl group in the hydroxylated styrene-butadiene rubber is 1:1.

[0146] By using the integral area calculation of the corresponding structure in the hydrogen nuclear magnetic spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 57 mol%, 12 mol%, 1.5 mol%, 5.0 mol%, and 1.0 mol%, respectively, that is, the phenolic side chain content was 1.0 mol%.

[0147] Embodiment 19

[0148] The preparation method is basically the same as that of Example 1, except that the amount of phenolic antioxidant 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid used in the esterification reaction in step (3) is 48.5 g, that is, the molar ratio of the phenolic antioxidant to the hydroxyl group in the hydroxylated styrene-butadiene rubber is 3:1.

[0149] By using the integral area calculation of the corresponding structure in the H-NMR spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 57 mol%, 12 mol%, 1.5 mol%, 4.2 mol%, and 1.8 mol%, respectively, that is, the content of phenolic side chains was 1.8 mol%.

[0150] Embodiment 20

[0151] The preparation method is basically the same as that of Example 1, except that the acylation catalyst used in the activation reaction in step (3) is 4-pyrrolidinopyridine in an amount of 4.3 g, that is, the molar ratio of the acylation catalyst to the hydroxyl group in the hydroxylated styrene-butadiene rubber is 0.5:1.

[0152] By using the integral area calculation of the corresponding structure in the hydrogen nuclear magnetic spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 57 mol%, 12 mol%, 1.5 mol%, 2.4 mol%, and 3.6 mol%, respectively, that is, the phenolic side chain content was 3.6 mol%.

[0153] Embodiment 21

[0154] The preparation method is basically the same as that of Example 1, except that the acylation catalyst used in the activation reaction in step (3) is 1-hydroxybenzotriazole, and the amount used is 3.8 g, that is, the molar ratio of the acylation catalyst to the hydroxyl group in the hydroxylated styrene-butadiene rubber is 0.5:1.

[0155] By using the integral area calculation of the corresponding structure in the hydrogen nuclear magnetic spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 57 mol%, 12 mol%, 1.5 mol%, 4.7 mol%, and 1.3 mol%, respectively, that is, the content of phenolic side chains was 1.3 mol%.

[0156] Embodiment 22

[0157] The preparation method is basically the same as that of Example 18, except that the amount of the acylation catalyst 4-pyrrolidinopyridine (4-PPY) used in the activation reaction in step (3) is 1.7 g, that is, the molar ratio of 4-pyrrolidinopyridine to the hydroxyl group in the hydroxylated styrene-butadiene rubber is 0.2:1.

[0158] By using the integral area calculation of the corresponding structure in the hydrogen nuclear magnetic spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 57 mol%, 12 mol%, 1.5 mol%, 4.0 mol%, and 2.0 mol%, respectively, that is, the phenolic side chain content was 2.0 mol%.

[0159] Embodiment 23

[0160] The preparation method is basically the same as that of Example 18, except that the amount of acylation catalyst 4-pyrrolidinopyridine (4-PPY) used in the activation reaction in step (3) is 8.6 g, that is, the molar ratio of 4-pyrrolidinopyridine to the hydroxyl group in the hydroxylated styrene-butadiene rubber is 1:1.

[0161] By using the integral area calculation of the corresponding structure in the hydrogen nuclear magnetic spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 57 mol%, 12 mol%, 1.5 mol%, 2.2 mol%, and 3.8 mol%, respectively, that is, the phenolic side chain content was 3.8 mol%.

[0162] Embodiment 24

[0163] The preparation method is basically the same as that of Example 18, except that the di-electron affinity condensing agent used in the esterification reaction in step (3) is dicyclohexylcarbodiimide, and its amount is 17.6 g, that is, the molar ratio of the di-electron affinity condensing agent to the hydroxyl group in the hydroxylated styrene-butadiene rubber is 1.5:1.

[0164] By using the integral area calculation of the corresponding structure in the hydrogen nuclear magnetic spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 57 mol%, 12 mol%, 1.5 mol%, 4.5 mol%, and 1.5 mol%, respectively, that is, the content of phenolic side chains was 1.5 mol%.

[0165] Embodiment 25

[0166] The preparation method is basically the same as that of Example 18, except that the di-electron affinity condensing agent used in the esterification reaction in step (3) is diisopropylcarbodiimide, and its amount is 10.8 g, that is, the molar ratio of the di-electron affinity condensing agent to the hydroxyl group in the hydroxylated styrene-butadiene rubber is 1.5:1.

[0167] By using the integral area calculation of the corresponding structure in the hydrogen nuclear magnetic spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 57 mol%, 12 mol%, 1.5 mol%, 3.8 mol%, and 2.2 mol%, respectively, that is, the content of phenolic side chains was 2.2 mol%.

[0168] Embodiment 26

[0169] The preparation method is basically the same as that of Example 18, except that the amount of the double electron affinity condensing agent 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride used in the esterification reaction in step (3) is 11.1 g, that is, the molar ratio of 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride to the hydroxyl group in the hydroxylated styrene-butadiene rubber is 1:1.

[0170] By using the integral area calculation of the corresponding structure in the hydrogen nuclear magnetic spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 57 mol%, 12 mol%, 1.5 mol%, 3.2 mol%, and 2.8 mol%, respectively, that is, the phenolic side chain content was 2.8 mol%.

[0171] Embodiment 27

[0172] The preparation method is basically the same as that of Example 18, except that the amount of the double electron affinity condensing agent 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride used in the esterification reaction in step (3) is 33.3 g, that is, the molar ratio of 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride to the hydroxyl group in the hydroxylated styrene-butadiene rubber is 3:1.

[0173] By using the integral area calculation of the corresponding structure in the hydrogen nuclear magnetic spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 57 mol%, 12 mol%, 1.5 mol%, 2.1 mol%, and 3.9 mol%, respectively, that is, the phenolic side chain content was 3.9 mol%.

[0174] Embodiment 28

[0175] The preparation method is basically the same as that of Example 18, except that in step (3), the activation reaction time is 4 h, the activation reaction temperature is 20°C, the esterification reaction time is 48 h, and the esterification reaction temperature is 20°C.

[0176] By using the integral area calculation of the corresponding structure in the hydrogen nuclear magnetic spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 57 mol%, 12 mol%, 1.5 mol%, 2.2 mol%, and 3.8 mol%, respectively, that is, the phenolic side chain content was 3.8 mol%.

[0177] Embodiment 29

[0178] The preparation method is basically the same as that of Example 18, except that in step (3), the activation reaction time is 2 h, the activation reaction temperature is 35°C, the esterification reaction time is 12 h, and the esterification reaction temperature is 35°C.

[0179] By using the integral area calculation of the corresponding structure in the hydrogen nuclear magnetic spectrum, it was found that the content percentages of the repeating units a, b, c, d, e, and f in the phenolic anti-aging styrene-butadiene rubber were 23.5 mol%, 57 mol%, 12 mol%, 1.5 mol%, 2.7 mol%, and 3.3 mol%, respectively, that is, the phenolic side chain content was 3.3 mol%.

[0180] Comparative Example 1

[0181] Commercial latex styrene butadiene rubber 1502.

[0182] Comparative Example 2

[0183] Styrene-butadiene rubber with added commercial antioxidant BHT: Plasticize 100g of styrene-butadiene rubber 1502 on a double-roller mixing mill, thinly pass it 1-2 times, appropriately widen the roller distance after it is evenly rolled, add 3g of commercial antioxidant BHT and thinly pass it 3 times, mix evenly, make triangle packages 3 times, roll it 3 times, adjust the roller distance to 2-3mm, and produce the sheet.

[0184] The phenolic anti-aging styrene-butadiene rubber prepared in the embodiment, the commercial emulsion-polymerized styrene-butadiene rubber 1502 (Comparative Example 1) and the styrene-butadiene rubber with commercial antioxidant BHT added (Comparative Example 2) were compared in terms of properties: after the mechanical properties were tested according to GB / T5282009, the same batch of specimens were placed in a hot oxygen aging oven at 100°C for 72 hours, the mechanical properties after aging were tested according to GB / T5282009, and the tensile product aging coefficient was calculated, the tensile product aging coefficient = (tensile strength after aging × elongation at break after aging) / (tensile strength before aging × elongation at break before aging) × 100%, and the test results are shown in Table 2 below:

[0185] Table 2

[0186]

[0187] As can be seen from Table 2, the polarity of the rubber is further enhanced after the introduction of phenolic side chains into the rubber molecular chains of Examples 1-29 before thermal oxidative aging, and the tensile strength of the rubber is enhanced as the content of phenolic side chains increases; at the same time, the increase in the number of large side chains increases the spacing between the molecular chains, playing a certain role as a plasticizer, and increasing the elongation at break; after thermal oxidative aging, the tensile strength of Examples 1-29 increases and the elongation at break decreases, while the tensile strength and elongation at break of commercial styrene-butadiene rubber 1502 and styrene-butadiene rubber with commercial antioxidant BHT added are reduced. The thermal oxidative aging process of styrene-butadiene rubber is mainly cross-linked, the rubber becomes hard and brittle, and the elongation at break decreases; since phenolic anti-aging styrene-butadiene rubber contains chlorine atoms, when aged at 100°C, zinc oxide and chloride ions undergo ionic cross-linking, which increases the tensile strength and reduces the elongation at break; commercial styrene-butadiene rubber 1502 and styrene-butadiene rubber with commercial antioxidant BHT do not have such ionic cross-linking, and the tensile strength decreases after aging.

[0188] The tensile product aging coefficient can characterize the performance change of rubber before and after aging. Compared with commercial styrene butadiene rubber 1502 and styrene butadiene rubber added with commercial antioxidant BHT, Examples 1-29 have a higher tensile product aging coefficient, indicating that they have better resistance to heat and oxygen aging.

Claims

1. A phenolic anti-aging styrene-butadiene rubber, characterized in that The phenolic anti-aging styrene-butadiene rubber structural formula is: In the formula, a: 15-35 mol%, b: 40-80 mol%, c: 5-35 mol%, d: 0.5-10 mol%, e: 0.5-10 mol%, f: 0.5-10 mol%, preferably a: 20-30 mol%, b: 30-45 mol%, c: 10-20 mol%, d: 1-5 mol%, e: 1-5 mol%, f: 1-5 mol%.

2. A method for preparing phenolic anti-aging styrene-butadiene rubber as claimed in claim 1, characterized in that The method comprises: Firstly, epoxidation reaction is carried out on styrene butadiene rubber by using meta-chloroperoxybenzoic acid, then epoxy ring-opening reaction is carried out with hydrochloric acid, and finally esterification reaction is carried out with a phenolic antioxidant to prepare the phenolic anti-aging styrene butadiene rubber.

3. The method for preparing the phenolic anti-aging styrene-butadiene rubber according to claim 2, characterized in that The method comprises: (1) adding a m-chloroperbenzoic acid solution dropwise into a styrene-butadiene rubber solution to carry out an epoxidation reaction, and after the reaction is completed, post-treating to obtain an epoxidized styrene-butadiene rubber; (2) adding a hydrochloric acid solution dropwise to a solution of the epoxidized styrene butadiene rubber dissolved in solvent A to carry out an epoxy ring-opening reaction, and after the reaction is completed, post-treating to obtain a hydroxylated styrene butadiene rubber; (3) adding a phenolic antioxidant and an acylation catalyst to a solution of the hydroxylated styrene butadiene rubber dissolved in solvent B for activation reaction, then adding a di-electron affinity condensing agent for esterification reaction, and after the reaction is completed, post-treating to obtain the phenolic anti-aging styrene butadiene rubber.

4. The method for preparing phenolic anti-aging styrene-butadiene rubber according to claim 3, characterized in that: In step (1): The solvent of the meta-chloroperbenzoic acid solution is tetrahydrofuran; and / or, The solvent of the styrene-butadiene rubber solution is at least one of cyclohexane, toluene, xylene, tetrahydrofuran, n-hexane and dichloromethane.

5. The method for preparing the phenolic anti-aging styrene-butadiene rubber according to claim 3, characterized in that: In step (1): The concentration of the meta-chloroperbenzoic acid solution is 20wt% to 50wt%; and / or, The concentration of the styrene-butadiene rubber solution is 5wt% to 15wt%; and / or, The molar ratio of the meta-chloroperbenzoic acid to the carbon-carbon double bonds in the styrene-butadiene rubber is (0.10-0.20):1, preferably (0.12-0.15):

1.

6. The method for preparing the phenolic anti-aging styrene-butadiene rubber according to claim 3, characterized in that: In step (1): The epoxidation reaction is carried out at a temperature of 25°C to 45°C and for a time of 1 to 4 hours; and / or, The post-processing includes: Adding alkaline solution to the reaction solution to adjust the pH value to 7-8, flocculating in a flocculant, and drying to obtain the epoxidized styrene-butadiene rubber; Preferably, The alkali solution is at least one of sodium hydroxide solution, sodium bicarbonate solution and ammonia water; and / or, The flocculant is at least one of anhydrous ethanol and anhydrous methanol.

7. The method for preparing the phenolic anti-aging styrene-butadiene rubber according to claim 3, characterized in that: In step (2): The solvent A is at least one of tetrahydrofuran, toluene, xylene and dichloromethane; and / or, The concentration of the hydrochloric acid solution is 20wt% to 36.5wt%; and / or, The concentration of the epoxidized styrene-butadiene rubber dissolved in solvent A is 5wt% to 15wt%; and / or, The molar ratio of the hydrochloric acid to the epoxy group in the epoxidized styrene-butadiene rubber is (0.5-3):1, preferably (1-1.5):

1.

8. The method for preparing phenolic anti-aging styrene-butadiene rubber according to claim 3, characterized in that: In step (2): The temperature of the epoxy ring-opening reaction is 15°C to 35°C and the time is 2 to 4 hours; and / or, The post-processing includes: After flocculating the reaction solution in a flocculant, drying is performed to obtain the hydroxylated styrene-butadiene rubber; Preferably, The flocculant is at least one of anhydrous ethanol and anhydrous methanol.

9. The method for preparing phenolic anti-aging styrene-butadiene rubber according to claim 3, characterized in that: In step (3): The solvent B is at least one of dichloromethane, chloroform, ether, carbon tetrachloride and toluene; and / or, The concentration of the solution of the hydroxylated styrene-butadiene rubber dissolved in the solvent B is 5wt% to 15wt%; and / or, The phenolic antioxidant is a phenolic antioxidant containing a carboxyl group; Preferably, The carboxyl-containing phenolic antioxidant is at least one of 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid, 3,5-di-tert-butyl-4-hydroxybenzoic acid, 3,5-di-tert-butyl-4-hydroxyphenylacetic acid, 3,5-di-tert-butyl salicylic acid, and 3,4,5-trihydroxybenzoic acid (gallic acid); and / or The molar ratio of the phenolic antioxidant to the hydroxyl group in the hydroxylated styrene-butadiene rubber is (1-3):1, preferably (1.2-1.5):1; and / or, The acylation catalyst is at least one of 4-dimethylaminopyridine, 4-pyrrolidinylpyridine, 1-hydroxybenzotriazole, and N-hydroxy-7-azabenzotriazole; and / or, The molar ratio of the acylation catalyst to the hydroxyl group in the hydroxylated styrene-butadiene rubber is (0.2-1):1, preferably (0.4-0.6):1; and / or, The di-electron affinity condensing agent is a carbodiimide condensing agent; Preferably, The carbodiimide condensing agent is at least one of 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride, dicyclohexylcarbodiimide, and diisopropylcarbodiimide; and / or, The molar ratio of the di-electron affinity condensing agent to the hydroxyl group in the hydroxylated styrene-butadiene rubber is (1-3):1, preferably (1.5-1.8):

1.

10. The method for preparing phenolic anti-aging styrene-butadiene rubber according to claim 3, characterized in that: In step (3): The activation reaction time is 1 to 4 hours, and the temperature is 20° C. to 35° C.; and / or, The esterification reaction time is 12 to 48 hours, and the temperature is 20° C. to 35° C.; and / or, During the esterification reaction, a protective gas is introduced; Preferably, The protective gas is at least one of nitrogen and inert gas; More preferably, The inert gas is argon; and / or, The post-processing includes: After the reaction solution is co-precipitated in solvent C, it is washed and dried to obtain the phenolic anti-aging styrene-butadiene rubber; Preferably, The solvent C is at least one of ethanol and methanol.

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