Aging-resistant, flex fatigue-resistant tire side rubber and method of making same

Abstract

This invention belongs to the field of rubber, and specifically relates to an aging-resistant and flexural-resistant tire sidewall rubber and its preparation method. Specifically, this invention relates to a composition for preparing rubber and a method for preparing rubber. The rubber obtained by this invention can guarantee both the aging resistance and the flexural crack resistance and fatigue resistance of the tire sidewall rubber. The materials required for its preparation are inexpensive and readily available, the preparation process is simple, and it exhibits outstanding resistance to flexural cracking and excellent aging resistance.

Description

Technical Field

[0001] This invention belongs to the field of rubber, and specifically relates to a composition for preparing rubber and a method for preparing rubber. This invention also relates to rubber prepared by said composition or method. Background Technology

[0002] Because the tire sidewall is constantly undergoing cyclic compression and deformation during vehicle operation, it is continuously damaged by the reaction of ozone and ultraviolet rays, and is also subjected to external mechanical forces. Therefore, the sidewall rubber compound is typically required to possess excellent resistance to aging, abrasion, tearing, radial and circumferential cracking, and good fatigue life. Furthermore, the performance of the tire sidewall is also crucial from the perspective of appearance and durability. The sidewall is the part of the tire subjected to extremely frequent flexural deformation and should have excellent resistance to flexural cracking.

[0003] Currently, most tire sidewall rubber systems are made of pure natural rubber (NR) or a blend of natural rubber and butadiene rubber (NR / BR). NR has excellent resistance to flexural crack propagation, while BR has excellent resistance to flexural crack initiation. However, these blends still have drawbacks such as poor resistance to flexural cracking and poor resistance to heat and oxygen aging. Compared to other parts of the tire, the sidewall is more susceptible to aging and cracking due to sunlight, heat, oxygen, and ozone. Therefore, the sidewall has higher requirements for aging resistance. At the same time, the sidewall is the part of the tire subjected to extremely frequent flexural deformation, and should have excellent resistance to flexural cracking. Therefore, developing high-performance, low-cost, aging-resistant, and flexural-resistant rubber materials is essential and can generate significant economic and social benefits. Summary of the Invention

[0004] This invention aims to improve the aging resistance and flexural strength of tire sidewall rubber while reducing production costs. It employs a compound of natural rubber and butadiene rubber, modified with a self-made aging-resistant and flexural-strength elastomer, carbon black, silica, cellulose, high-temperature insoluble sulfur, anti-reversion agent, environmentally friendly aromatic oil, microcrystalline wax HG75, accelerator, nano zinc oxide, stearic acid, and antioxidants. This modification ensures both the aging resistance and flexural crack resistance of the tire sidewall rubber, as well as good fatigue resistance. The required materials are inexpensive and readily available, the preparation process is simple, and the resulting product exhibits outstanding flexural crack resistance and excellent aging resistance.

[0005] In one aspect, this application provides a composition for preparing rubber, comprising, by weight: 100 parts raw rubber, 5-15 parts (e.g., 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 parts) of a self-made aging-resistant and flexural-resistant elastomer, 20-30 parts (e.g., 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30 parts) of carbon black, 6-9 parts (e.g., 6, 7, 8, or 9 parts) of silica, 3 parts of cellulose, 1.5-2 parts (e.g., 1.5, 1.6, 1.7, 1.8, 1.9, or 2 parts) of high-temperature insoluble sulfur HDOT-20, 1-2 parts (e.g., 1, 1.5, or 2 parts) of an anti-reversion agent, 4-8 parts (e.g., 4, 5, 6, 7, or 8 parts) of environmentally friendly aromatic oil V500, and HG75 microcrystalline wax. 2 parts, 1.5 to 2.5 parts of accelerator (e.g., 1.5, 2 or 2.5 parts), 2 to 4 parts of nano zinc oxide (e.g., 2, 3 or 4 parts), 2 to 3 parts of stearic acid (e.g., 2, 2.5 or 3 parts), and 3 to 4 parts of antioxidant (e.g., 3, 3.5 or 4 parts).

[0006] The raw rubber is 70-80 parts of natural rubber (e.g., 70, 71, 72, 73, 74, 75, 76, 77, 78, 79 or 80 parts) and 20-30 parts of butadiene rubber (e.g., 20, 21, 22, 23, 24, 25, 26, 27, 28, 29 or 30 parts);

[0007] The self-made aging-resistant and flexural-resistant elastomer is a blend of trans-butadiene rubber grafted with maleic anhydride (TBIR-g-MAH) and styrene-butadiene-styrene block copolymer (SBS).

[0008] The aging-resistant and flexural-resistant elastomer is prepared by a method comprising the following steps:

[0009] (1) Weigh 85 to 90 parts (e.g., 85, 86, 87, 88, 89 or 90 parts) of trans-butyl pentadiene rubber (TBIR), 3 to 4 parts of benzoyl peroxide (BPO), and 5 to 10 parts (e.g., 5, 6, 7, 8, 9 or 10 parts) of maleic anhydride (MAH);

[0010] (2) Trans-butadiene rubber and xylene are added to a flask, stirred and heated to 70°C to 110°C (e.g., 100°C) to fully dissolve the trans-butadiene rubber in the solvent; in some embodiments, the mass ratio of trans-butadiene rubber to xylene is 1:5 or more, for example 1:5 to 1:6.

[0011] (3) Add the maleic anhydride monomer and benzoyl peroxide to the flask in proportion and stir thoroughly;

[0012] (4) After the reaction is complete, precipitate the product with acetone, then filter it with a funnel and dry it.

[0013] (5) The dried product is extracted in acetone for 2-4 hours (e.g., 3 hours) using an extractor to purify it and remove unreacted monomers and initiators.

[0014] (6) The purified product is vacuum dried at 55-65°C (e.g., 60°C) to constant weight for later use, to obtain the trans-butadiene rubber grafted maleic anhydride product.

[0015] (7) Weigh 80 to 100 parts (e.g., 80, 85, 90, 95 or 100 parts) of trans-butadiene-capital rubber grafted with maleic anhydride (TBIR-g-MAH) and 80 to 100 parts (e.g., 80, 85, 90, 95 or 100 parts) of styrene-butadiene-styrene block copolymer (SBS). Set the temperature of the torque rheometer to 100℃ to 125℃ (e.g., 110℃) and the rotor speed to 40 rpm to 70 rpm (e.g., 50 rpm). Add SBS and TBIR-g-MAH in sequence, mix for 10 min to 15 min, and take out the self-made aging-resistant and flexural-resistant elastomer.

[0016] The trans-butadiene-isoprene rubber used in this invention refers to trans-1,4-butadiene-isoprene copolymer rubber (TBIR), which is a multi-block copolymer composed of isoprene and butadiene structural units with high trans-1,4-structure.

[0017] The anti-sulfurization reversion agent is selected from HTS, PK-900, or a combination thereof;

[0018] The antioxidant is selected from RD, 4020, 4030, 4010NA, DFC-34 or any combination thereof;

[0019] The accelerator is selected from DPG, CZ, TBBS-80 or any combination thereof;

[0020] The carbon black is selected from N375, N330, N234 or any combination thereof.

[0021] In this article, HTS and PK-900 are anti-sulfurization reversion agent brands; RD, 4020, 4030, 4010NA, and DFC-34 are antioxidant brands; DPG, CZ, and TBBS-80 are accelerator brands; HDOT-20 is a brand of insoluble sulfur; N375, N330, and N234 are carbon black brands; V500 is a brand of environmentally friendly aromatic oil; and HG75 is a brand of microcrystalline wax. All the above reagents are commercially available products. The names and CAS numbers of some reagents are as follows:

[0022]

[0023]

[0024] In one aspect, this application provides a method for preparing rubber, comprising using the composition of the present invention as a raw material; the method includes the following steps:

[0025] Step 1:

[0026] Adjust the rotor speed of the internal mixer (e.g., GK400 type internal mixer) to 50-55 r / min. -1 (e.g., 52r·min) -1 Add raw rubber, homemade aging-resistant and flexural elastomer, nano zinc oxide and stearic acid, press for 34-36s (e.g. 35s) → add carbon black, white carbon black and cellulose, mix until the temperature reaches 119-121℃ (e.g. 120℃) → add environmentally friendly aromatic oil, mix until the temperature reaches (150±5)℃ → discharge the rubber to obtain a first-stage compound;

[0027] Step Two:

[0028] Adjust the rotor speed of the internal mixer to 41-43 r / min. -1 (e.g. 42r·min) -1 Add a first-stage compound, microcrystalline wax and antioxidant, press for 29-31 seconds (e.g., 30 seconds) → mix until the temperature reaches (135±5)℃ → discharge the compound to obtain a second-stage compound.

[0029] Step 3:

[0030] Adjust the rotor speed of the internal mixer (e.g., the GK255 type internal mixer) to 19–21 r / min. -1 (e.g., 20 r·min) -1 Add three-stage compound rubber, sulfur, accelerator and anti-reversion agent, press for 34-36 seconds (e.g. 35 seconds), mix until the temperature reaches 102-104℃ (e.g. 103℃) → discharge the rubber.

[0031] In one aspect, this application provides a rubber obtained from the above-described composition or preparation method.

[0032] In some embodiments, the rubber of the present invention has one or more of the following characteristics:

[0033] (1) Tensile strength: 23-25 ​​MPa;

[0034] (2) 300% constant tensile stress: 15-17 MPa;

[0035] (3) Bending cycles: 3 million cycles without cracking;

[0036] (4) Ozone aging test (ozone concentration 50ppm, relative humidity 60%, temperature 40℃, elongation 20%): no cracking after 240h;

[0037] (5) Elongation at break / %: 550~575.

[0038] The above parameters can be measured by conventional methods in the art, such as those described in GB / T 528-2009, GB / T13934-2006 or GB / T 7726-2014.

[0039] In one aspect, this application provides the use of the rubber of the present invention in the manufacture of tires. In some embodiments, the rubber is used as the sidewall compound of a tire.

[0040] In one aspect, this application provides a product comprising, or made from, the rubber of the present invention. In some embodiments, the product is selected from tires, rubber tracks, conveyor belts, and shock absorbers.

[0041] This application also provides a vehicle or construction machinery that includes the tire of the present invention.

[0042] Beneficial effects of the invention

[0043] This invention improves the existing sidewall rubber formulation for engineering machinery tires, and the new formulation has the following advantages:

[0044] (1) The rubber compound prepared by the formulation components proposed in this invention has excellent aging resistance and flexural strength, especially excellent ozone aging resistance, which greatly improves the anti-cracking performance of rubber.

[0045] (2) A self-made aging-resistant and flexural-resistant elastomer that is perfectly compatible with the raw rubber system was added, which improved the aging resistance and flexural resistance while maintaining the strength.

[0046] (3) The prototype tire has improved 300% constant elongation stress and aging resistance, excellent flexural strength, and improved tire service life. Detailed Implementation

[0047] The embodiments of the present invention will be described in detail below with reference to examples. However, those skilled in the art will understand that the following examples are for illustrative purposes only and should not be considered as limiting the scope of the invention. Unless otherwise specified in the examples, conventional conditions or conditions recommended by the manufacturer are followed. Reagents or instruments whose manufacturers are not specified are all commercially available conventional products.

[0048] Example 1

[0049] A tire sidewall rubber with anti-aging and anti-flexural properties, characterized by: 80 parts natural rubber, 20 parts butadiene rubber, 8 parts self-made anti-aging and anti-flexural elastomer, 20 parts carbon black, 6 parts silica, 3 parts cellulose; 2 parts high-temperature insoluble sulfur, 1 part anti-reversion agent HTS, 1 part anti-reversion agent PK-900, 4 parts environmentally friendly aromatic oil V500, 2 parts microcrystalline wax HG75, 2.5 parts accelerator CZ, 2 parts nano zinc oxide, 2 parts stearic acid, and 4 parts antioxidant RD.

[0050] Step 1:

[0051] The mixing was carried out in a GK400 type internal mixer. The mixing rotor speed was 52 r / min. -1 Prepare raw rubber, homemade anti-aging and flexural elastomer, nano zinc oxide, stearic acid, press with a roller (35s) ​​→ add carbon black, white carbon black, cellulose, mix until the temperature reaches 120℃ → add environmentally friendly aromatic oil, mix until the temperature reaches (150±5)℃ → discharge the rubber.

[0052] Step Two:

[0053] The rotor speed for the two-stage mixing process is 42 r / min. -1 The mixing process is as follows: first stage of mixing rubber, microcrystalline wax and antioxidant, pressing with a roller (30s) → discharging rubber (135±5)℃;

[0054] Step 3:

[0055] The operation was carried out in a GK255 type internal mixer at a rotor speed of 20 r·min. -1 The mixing process is as follows: three-stage mixing of rubber, sulfur, accelerator, and anti-sulfurization reversion agent, pressing with a roller (35s), mixing until the temperature reaches 103℃ → discharging the rubber.

[0056] An aging-resistant and flexurally resistant elastomer is prepared by a method comprising the following steps:

[0057] (1) Weigh out 85 parts of trans-butadiene rubber (TBIR), 4 parts of benzoyl peroxide (BPO), and 6 parts of maleic anhydride (MAH);

[0058] (2) Trans-butadiene rubber and xylene are added to a flask at a mass ratio of 1:6. The mixture is stirred and heated to 100°C to fully dissolve the trans-butadiene rubber in the solvent.

[0059] (3) Add the maleic anhydride monomer and benzoyl peroxide to the flask in proportion and stir thoroughly;

[0060] (4) After the reaction is complete, precipitate the product with acetone, then filter it with a funnel and dry it.

[0061] (5) The dried product was extracted in acetone for 3 hours using an extractor to purify it and remove unreacted monomers and initiators.

[0062] (6) The purified product is vacuum dried at 60°C to constant weight for later use to obtain the trans-butadiene rubber grafted maleic anhydride product.

[0063] (7) Weigh 100 parts of trans-butadiene-pentylene rubber grafted maleic anhydride (TBIR-g-MAH) and 100 parts of styrene-butadiene-styrene block copolymer (SBS). Set the temperature of the torque rheometer to 110℃ and the rotor speed to 50rpm. Add SBS and TBIR-g-MAH sequentially.

[0064] Mix for 15 minutes, then remove to obtain a self-made aging-resistant and flexural-resistant elastomer.

[0065] Example 2

[0066] A tire sidewall rubber with anti-aging and anti-flexural properties, characterized by: 80 parts natural rubber, 20 parts butadiene rubber, 10 parts self-made anti-aging and anti-flexural elastomer, 25 parts carbon black, 7 parts silica, 3 parts cellulose; 2 parts high-temperature insoluble sulfur HDOT-20, 2 parts anti-sulfurization reversion agent HTS, 6 parts environmentally friendly aromatic oil V500, 2 parts microcrystalline wax HG75, 2 parts accelerator CZ, 3 parts nano zinc oxide, 3 parts stearic acid, and 4 parts anti-aging agent 4020.

[0067] Step 1:

[0068] The mixing was carried out in a GK400 type internal mixer. The mixing rotor speed was 52 r / min. -1 Prepare raw rubber, homemade anti-aging and flexural elastomer, nano zinc oxide, stearic acid, press with a roller (35s) ​​→ add carbon black, white carbon black, cellulose, mix until the temperature reaches 120℃ → add environmentally friendly aromatic oil, mix until the temperature reaches (150±5)℃ → discharge the rubber.

[0069] Step Two:

[0070] The rotor speed for the two-stage mixing process is 42 r / min. -1 The mixing process is as follows: first stage of mixing rubber, microcrystalline wax and antioxidant, pressing with a roller (30s) → discharging rubber (135±5)℃;

[0071] Step 3:

[0072] The operation was carried out in a GK255 type internal mixer at a rotor speed of 20 r·min. -1 The mixing process is as follows: three-stage mixing of rubber, sulfur, accelerator, and anti-sulfurization reversion agent, pressing with a roller (35s), mixing until the temperature reaches 103℃ → discharging the rubber.

[0073] An aging-resistant and flexurally resistant elastomer is prepared by a method comprising the following steps:

[0074] (1) Weigh out 85 parts of trans-butadiene rubber (TBIR), 4 parts of benzoyl peroxide (BPO), and 6 parts of maleic anhydride (MAH);

[0075] (2) Trans-butadiene rubber and xylene are added to a flask at a mass ratio of 1:6. The mixture is stirred and heated to 100°C to fully dissolve the trans-butadiene rubber in the solvent.

[0076] (3) Add the maleic anhydride monomer and benzoyl peroxide to the flask in proportion and stir thoroughly;

[0077] (4) After the reaction is complete, precipitate the product with acetone, then filter it with a funnel and dry it.

[0078] (5) The dried product was extracted in acetone for 3 hours using an extractor to purify it and remove unreacted monomers and initiators.

[0079] (6) The purified product is vacuum dried at 60°C to constant weight for later use to obtain the trans-butadiene rubber grafted maleic anhydride product.

[0080] (7) Weigh 100 parts of trans-butadiene-pentylene rubber grafted maleic anhydride (TBIR-g-MAH) and 100 parts of styrene-butadiene-styrene block copolymer (SBS). Set the temperature of the torque rheometer to 110℃ and the rotor speed to 50rpm. Add SBS and TBIR-g-MAH in sequence, mix for 15min, and take out the self-made aging-resistant and flexural-resistant elastomer.

[0081] Example 3

[0082] A tire sidewall rubber with anti-aging and anti-flexural properties, characterized by: 80 parts natural rubber, 20 parts butadiene rubber, 15 parts self-made anti-aging and anti-flexural elastomer, 30 parts carbon black, 9 parts silica, 3 parts cellulose; 2 parts high-temperature insoluble sulfur HDOT-20, 1 part anti-reversion agent HTS, 1 part anti-reversion agent PK-900, 6 parts environmentally friendly aromatic oil V500, 2 parts microcrystalline wax HG75, 2 parts accelerator CZ, 3 parts nano zinc oxide, 3 parts stearic acid, and 3 parts anti-aging agent 4020.

[0083] Step 1:

[0084] The mixing was carried out in a GK400 type internal mixer. The mixing rotor speed was 52 r / min. -1Prepare raw rubber, homemade anti-aging and flexural elastomer, nano zinc oxide, stearic acid, press with a roller (35s) ​​→ add carbon black, white carbon black, cellulose, mix until the temperature reaches 120℃ → add environmentally friendly aromatic oil, mix until the temperature reaches (150±5)℃ → discharge the rubber.

[0085] Step Two:

[0086] The rotor speed for the two-stage mixing process is 42 r / min. -1 The mixing process is as follows: first stage of mixing rubber, microcrystalline wax and antioxidant, pressing with a roller (30s) → discharging rubber (135±5)℃;

[0087] Step 3:

[0088] The operation was carried out in a GK255 type internal mixer at a rotor speed of 20 r·min. -1 The mixing process is as follows: three-stage mixing of rubber, sulfur, accelerator, and anti-sulfurization reversion agent, pressing with a roller (35s), mixing until the temperature reaches 103℃ → discharging the rubber.

[0089] An aging-resistant and flexurally resistant elastomer is prepared by a method comprising the following steps:

[0090] (1) Weigh out 85 parts of trans-butadiene rubber (TBIR), 4 parts of benzoyl peroxide (BPO), and 6 parts of maleic anhydride (MAH);

[0091] (2) Trans-butadiene rubber and xylene are added to a flask at a mass ratio of 1:6. The mixture is stirred and heated to 100°C to fully dissolve the trans-butadiene rubber in the solvent.

[0092] (3) Add the maleic anhydride monomer and benzoyl peroxide to the flask in proportion and stir thoroughly;

[0093] (4) After the reaction is complete, precipitate the product with acetone, then filter it with a funnel and dry it.

[0094] (5) The dried product was extracted in acetone for 3 hours using an extractor to purify it and remove unreacted monomers and initiators.

[0095] (6) The purified product is vacuum dried at 60°C to constant weight for later use to obtain the trans-butadiene rubber grafted maleic anhydride product.

[0096] (7) Weigh 100 parts of trans-butadiene-pentylene rubber grafted maleic anhydride (TBIR-g-MAH) and 100 parts of styrene-butadiene-styrene block copolymer (SBS). Set the temperature of the torque rheometer to 110℃ and the rotor speed to 50rpm. Add SBS and TBIR-g-MAH in sequence, mix for 15min, and take out the self-made aging-resistant and flexural-resistant elastomer.

[0097] Comparative Example 1

[0098] This comparative ratio is made from the following raw materials in parts by weight: 80 parts natural rubber, 20 parts butadiene rubber, 25 parts carbon black, 7 parts silica, 2 parts sulfur, 6 parts environmentally friendly aromatic oil V500, 2 parts microcrystalline wax HG75, 2 parts accelerator CZ, 3 parts zinc oxide, 3 parts stearic acid, and 4 parts anti-aging agent 4020.

[0099] Raw rubber is placed in an open mixing mill and plasticized for 2 minutes. After the raw rubber wraps around the rollers, antioxidant, zinc oxide, stearic acid, microcrystalline wax, carbon black, silica, and environmentally friendly aromatic oil are added sequentially and mixed. After the rubber has absorbed the powder, it is repeatedly rolled in a triangular pattern. Finally, sulfur and accelerator are added, and the roller gap is adjusted to 2 mm before sheeting. After the sheet rests for 12 hours, it is placed in a mold and vulcanized in a flat vulcanizing machine at 155℃ for 10 minutes.

[0100] The performance test results of several embodiments are shown in Table 1.

[0101] Table 1 Results of rubber performance tests

[0102]

[0103] Although specific embodiments of the invention have been described in detail, those skilled in the art will understand that various modifications and variations can be made to the details based on all the teachings disclosed, and all such changes are within the scope of protection of the invention. The full scope of the invention is given by the appended claims and any equivalents thereof.

Claims

1. A composition for preparing rubber, comprising, by weight: 100 parts raw rubber, 5-15 parts self-made aging-resistant and flexural-resistant elastomer, 20-30 parts carbon black, 6-9 parts silica, 3 parts cellulose, 1.5-2 parts high-temperature insoluble sulfur HDOT-20, 1-2 parts anti-reversion agent, 4-8 parts environmentally friendly aromatic oil V500, 2 parts microcrystalline wax HG75, 1.5-2.5 parts accelerator, 2-4 parts nano zinc oxide, 2-3 parts stearic acid, and 3-4 parts antioxidant; The raw rubber is composed of 70-80 parts of natural rubber and 20-30 parts of butadiene rubber. The self-made aging-resistant and flexural-resistant elastomer is a blend of trans-butadiene rubber grafted with maleic anhydride and styrene-butadiene-styrene block copolymer. The aging-resistant and flexural-resistant elastomer is prepared by a method comprising the following steps: (1) Weigh 85-90 parts of trans-butadiene rubber, 3-4 parts of benzoyl peroxide, and 5-10 parts of maleic anhydride; (2) Add trans-butadiene rubber and xylene to the flask, stir and heat to 70℃~110℃ to fully dissolve the trans-butadiene rubber in the solvent; (3) Add maleic anhydride monomer and benzoyl peroxide to the flask in proportion and stir thoroughly; (4) After the reaction is complete, precipitate the product with acetone, then filter it through a funnel and dry it. (5) Extract the dried product in acetone for 2-4 hours using an extractor to purify it and remove unreacted monomers and initiators; (6) The purified product was vacuum dried at 55-65℃ to constant weight for later use to obtain trans-butadiene rubber grafted with maleic anhydride. (7) Weigh 80-100 parts of trans-butadiene-pentadiene rubber grafted with maleic anhydride and 80-100 parts of styrene-butadiene-styrene block copolymer. Set the temperature of the torque rheometer to 100℃-125℃ and the rotor speed to 40rpm-70rpm. Add SBS and TBIR-g-MAH in sequence, mix for 10min-15min, and take out the self-made aging-resistant and flexural-resistant elastomer. The anti-sulfurization reversion agent is selected from HTS, PK-900, or a combination thereof; The antioxidant is selected from RD, 4020, 4030, 4010NA, DFC-34 or any combination thereof; The accelerator is selected from DPG, CZ, TBBS-80 or any combination thereof; The carbon black is selected from N375, N330, N234 or any combination thereof.

2. The composition according to claim 1, step (5) is: extracting the dried product in acetone for 3 hours using an extractor to purify it and remove unreacted monomers and initiators.

3. The composition according to claim 1 or 2, step (6) is: the purified product is vacuum dried at 60°C to constant weight for later use, to obtain the trans-butadiene rubber grafted maleic anhydride product.

4. A method for preparing rubber, comprising using the composition according to any one of claims 1-3 as a raw material; the method comprising the following steps: Step 1: Adjust the rotor speed of the internal mixer to 50~55 r·min -1 Add raw rubber, homemade anti-aging and flexural elastomer, nano zinc oxide and stearic acid, press for 34~36 s → add carbon black, white carbon black and cellulose, mix until the temperature reaches 119~121℃ → add environmentally friendly aromatic oil, mix until the temperature reaches 150±5℃ → discharge the rubber to obtain a first-stage compound rubber. Step Two: Adjust the rotor speed of the internal mixer to 41~43 r·min -1 Add a first-stage compound, microcrystalline wax and antioxidant, press with a roller for 29~31 s → mix until the temperature reaches 135±5℃ → discharge the glue to obtain a second-stage compound; Step 3: Adjust the rotor speed of the internal mixer to 19~21 r·min -1 Add the three-stage compound rubber, sulfur, accelerator and anti-reversion agent, press the roller for 34~36 s, and mix until the temperature reaches 102~104 ℃ → discharge the rubber.

5. The method according to claim 4, wherein step three is: adjusting the rotor speed of the internal mixer to 20 r·min. -1 Add the three-stage compound rubber, sulfur, accelerator and anti-reversion agent, press the roller for 34~36 s, and mix until the temperature reaches 102~104 ℃ → discharge the rubber.

6. A rubber obtained by the composition of any one of claims 1-3 or the method of claim 4 or 5.

7. The rubber according to claim 6, wherein it has one or more of the following characteristics: (1) Tensile strength: 23~25MPa; (2) 300% constant elongation stress: 15~17MPa; (3) Bending cycles: 3 million cycles without cracking; (4) Ozone aging test: ozone concentration 50ppm, relative humidity 60%, temperature 40℃, elongation 20%, no cracking after 240h; (5) Elongation at break / %: 550~575.

8. Use of the rubber of claim 6 or 7 in the manufacture of tires.

9. The use according to claim 8, wherein the rubber is used as a sidewall compound for a tire.

10. A product comprising, or made from, the rubber of claim 6 or 7.

11. The product according to claim 10, wherein the product is selected from tires, rubber tracks, conveyor belts, and shock absorbers.

12. A vehicle or construction machinery comprising the tire as described in claim 11.

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