Tread base rubber material, preparation method and all-steel-wire truck radial tire

Abstract

The invention relates to a tread base rubber material, a preparation method and an all-steel-wire truck radial tire, and belongs to the technical field of tire rubber materials. The rubber material comprises 100 parts of natural rubber, 10-25 parts of high abrasion furnace black, 10-25 parts of bio-based white carbon black, 10-20 parts of white carbon black, 2-5 parts of a silane coupling agent, 0.5-1.5 parts of a modified itaconic acid aid, 3-5 parts of zinc oxide and 1-3 parts of stearic acid; 2-4 parts of an anti-aging agent; 0.5-2 parts of tear-resistant resin and 1-3 parts of an accelerant; 0.5 to 1.5 parts of sulfur powder; and 0.5 to 1.5 parts of a zinc dithiophosphate cross-linking agent. Bio-based white carbon black is used for partially replacing high-abrasion-resistance furnace black, a cross-linking agent AP9 is used for overcoming the defects that stress at definite elongation and elongation are reduced, and a modified itaconic acid auxiliary is used for reducing the Pearn effect of a filling system, so that dynamic heat generation of the rubber material is obviously reduced, the anti-fatigue performance of the rubber material is improved, and the service life of a tire is prolonged.

Description

Technical Field

[0001] This invention belongs to the field of tire rubber material technology, specifically relating to a tread base rubber compound and its preparation method, and an all-steel radial truck tire. Background Technology

[0002] The information disclosed in this background technology section is only intended to enhance understanding of the overall background of the invention and should not necessarily be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to those skilled in the art.

[0003] The tread base rubber refers to the inner part of the top rubber of the tire crown, which, together with the sidewall rubber, is used to secure the top rubber of the crown, which is in direct contact with the road surface. During tire use, especially during long-distance driving, the tread undergoes periodic deformation. The interaction between the internal materials of the rubber compound leads to internal friction, converting kinetic energy into heat energy. The continuous accumulation of heat energy can cause a decrease in interlayer adhesion and local delamination. Under conditions of relatively short transport distance, heavy load, and poor road conditions, the friction between the internal materials of the tire and the friction between the tire and the road surface both result in greater rolling resistance, greater tread deformation, and higher heat generation, making tread delamination more likely.

[0004] With increasing environmental awareness within the industry, sustainable materials are being used in tire design to replace traditional materials, reducing reliance on fossil fuels such as petroleum and mitigating the adverse environmental impact of tire production. How to maintain or even improve tire performance while employing sustainable materials is a crucial technical challenge that needs to be addressed by those skilled in the art. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a tread base compound and its preparation method, as well as an all-steel radial truck tire. It incorporates bio-based silica as a sustainable material, along with modified itaconic acid additives and zinc dithiophosphate crosslinking agents to compensate for the decrease in modulus performance caused by bio-based silica. This significantly reduces the compound's loss factor (TanD) and dynamic heat generation, thereby mitigating delamination and crown detachment problems caused by heat generation.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows: In a first aspect, a tread base compound comprises the following components in parts by weight: 100 parts natural rubber, 10-25 parts high abrasion furnace black, 10-25 parts bio-based silica, 10-20 parts silica, 2-5 parts silane coupling agent, 0.5-1.5 parts modified itaconic acid additive, 3-5 parts zinc oxide, 1-3 parts stearic acid; 2-4 parts antioxidant; 0.5-2 parts tear-resistant resin, 1-3 parts accelerator; 0.5-1.5 parts sulfur powder; and 0.5-1.5 parts zinc dithiophosphate crosslinking agent.

[0007] Secondly, the preparation method of the above-mentioned tread base rubber compound includes the following steps: S1. Mix natural rubber, high abrasion-resistant furnace black, bio-based silica, modified itaconic acid additive, zinc oxide, stearic acid, antioxidant and tear-resistant resin, and knead at 115~165℃ to obtain a first-stage masterbatch. S2. Mix the first-stage masterbatch, silica and silane coupling agent, and knead at 115~158℃ to obtain the second-stage masterbatch. S3. Mix the second-stage masterbatch, accelerator, sulfur powder and zinc dithiophosphate crosslinking agent, and knead at 98~105℃ to obtain the tread base compound.

[0008] Thirdly, a heavy-duty all-steel radial tire, wherein the tread base rubber uses the aforementioned tread base rubber compound.

[0009] The beneficial effects of this invention are as follows: This invention uses bio-based silica to partially or completely replace high-abrasion-resistant furnace black, which leads to a decrease in tensile stress and elongation at break. The crosslinking agent AP9 can compensate for this decrease, improving processing safety. Modified itaconic acid additives effectively improve the dispersibility of the rubber compound filler system, reduce the Payne effect, effectively increase the tensile strength and elongation at break, and improve the fatigue resistance of the rubber compound. Through these formulation adjustments, the Mooney viscosity of the tread base compound is effectively reduced, lowering production energy consumption; dynamic heat generation of the rubber compound is significantly reduced, improving fatigue resistance; stress relaxation is improved, ensuring dimensional stability during semi-finished product production, improving tire uniformity, and extending tire lifespan. Detailed Implementation

[0010] It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present invention belongs.

[0011] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0012] One or more embodiments of the present invention provide a tread base compound comprising the following components in parts by weight: 100 parts natural rubber, 10-25 parts high abrasion furnace black, 10-25 parts bio-based silica, 10-20 parts silica, 2-5 parts silane coupling agent, 0.5-1.5 parts modified itaconic acid additive, 3-5 parts zinc oxide, 1-3 parts stearic acid; 2-4 parts antioxidant; 0.5-2 parts tear-resistant resin, 1-3 parts accelerator; 0.5-1.5 parts sulfur powder; and 0.5-1.5 parts zinc dithiophosphate crosslinking agent.

[0013] Optionally, the natural rubber includes one or more of STR20, SMR20, and SVR3L; it includes composite rubber or plasticized rubber obtained by processing natural rubber.

[0014] Optionally, the high abrasion-resistant carbon black includes one or more of N330 and N326, which gives the tread base compound the set mechanical properties.

[0015] Optionally, the bio-based silica includes easily dispersible bio-based silica made from marine diatomaceous earth as raw material; natural diatomaceous earth is the silicate remains of single-celled algae, mainly composed of hydrated amorphous SiO2, accounting for more than 70%, with other components being iron oxide, calcium oxide, magnesium oxide, and other organic matter; to meet the needs of photosynthesis, its surface has a well-developed porous structure; its particle size is between nanometers and micrometers, and the organic matter on the particle surface provides hydroxyl groups and hydrogen bonds, which can be well dispersed in rubber, providing certain reinforcing properties to rubber, with low hysteresis loss, low dynamic heat generation, and small compression set; when used in rubber, it has good processing performance, is easy to disperse, has low energy consumption, is safe to process, and can bring a low rolling resistance loss factor, preferably easily dispersible bio-based silica LH-3.

[0016] Optionally, the silica includes one or more of precipitated silica and hydrated silica; its function is to improve the tear resistance and reduce the heat generation of rubber materials.

[0017] Optionally, the silane coupling agent includes one or more of Si-69, SCA-S75X, and SCA-MS89E; its function is to improve the surface activity of silica, reduce silica agglomeration, and improve silica dispersibility in rubber.

[0018] Modified itaconic acid additives are obtained by surface modification of itaconic acid. Itaconic acid is a white crystalline substance produced from agricultural byproducts such as starch, sucrose, molasses, sawdust, and rice straw through fermentation, filtration, concentration, decolorization, crystallization, and drying. Its specific component is methylene succinic acid. By modifying the surface of itaconic acid, the linear length and flexibility of alkyl molecular chains can be effectively increased, the dispersibility of rubber filler systems can be effectively improved, and the Payne effect of filler systems can be reduced. Its molecular chains have unsaturated methylene groups, which can participate in the vulcanization reaction during vulcanization, improve the tensile strength of rubber, thereby effectively reducing the dynamic heat generation of the rubber compound, increasing the tensile strength and elongation at break of the rubber compound, and effectively improving the fatigue resistance of the rubber compound.

[0019] Zinc dithiophosphate crosslinking agent (AP9) is a rubber crosslinking agent with excellent anti-scorching properties and fast vulcanization speed. The vulcanized rubber has good flatness, high modulus, tensile strength, and improved dynamic fatigue resistance of the rubber compound. At the same time, it makes up for the low modulus defect caused by the use of diatomaceous earth in rubber.

[0020] Optionally, the tear-resistant resin includes one or more of petroleum resin SL6905L, RT260, and terpene phenolic resin; its function is to enhance the tear resistance and fatigue resistance of the rubber.

[0021] Optionally, the accelerator includes one or more of accelerators NS, CZ, and DM; its function is to improve the vulcanization efficiency of rubber and shorten the vulcanization time.

[0022] One or more embodiments of the present invention provide a method for preparing the above-mentioned tread base rubber compound, comprising the steps of: S1. Mix natural rubber, high abrasion-resistant furnace black, bio-based silica, modified itaconic acid additive, zinc oxide, stearic acid, antioxidant and tear-resistant resin, and knead at 115~165℃ to obtain a first-stage masterbatch. S2. Mix the first-stage masterbatch, silica and silane coupling agent, and knead at 115~158℃ to obtain the second-stage masterbatch. S3. Mix the second-stage masterbatch, accelerator, sulfur powder and zinc dithiophosphate crosslinking agent, and knead at 98~105℃ to obtain the tread base compound.

[0023] Optionally, in S1, the mixing time is 30-40 seconds at a speed of 40-50 rpm until the rubber temperature reaches 115-125℃; the top bolt is pressed on a second time, and the mixing time is 15-25 seconds at a speed of 35-45 rpm until the rubber temperature reaches 140-150℃; the top bolt is pressed on a third time, and the mixing time is 35-45 rpm until the rubber temperature reaches 155-165℃, and then the rubber is discharged.

[0024] Optionally, in S2, the mixture is stirred at 35-45 rpm for 20-25 seconds until the rubber compound temperature reaches 115-125℃; the top bolt is pressed on a second time, and the mixture is stirred at 35-45 rpm for 15-25 seconds until the rubber compound temperature reaches 140-150℃; the top bolt is pressed on a third time, and the mixture is stirred at 30-35 rpm for 15-25 seconds until the rubber compound temperature reaches 153-158℃, and then the rubber is discharged.

[0025] Optionally, in S3, the mixture is mixed at a speed of 15~25 rpm for 25~35 seconds; then mixed for 15~25 seconds under the top bolt for a second time, and mixed for 20~30 seconds under the top bolt for a third time until the rubber compound temperature reaches 98~105℃, and then discharged.

[0026] One or more embodiments of the present invention provide a heavy-duty all-steel radial tire, wherein the tread base rubber uses the above-mentioned tread base rubber compound.

[0027] Heavy-duty all-steel radial tires are commonly used in complex heavy-duty road conditions such as mines, construction sites, national highways, and expressways. Their performance challenges are concentrated on wear resistance, impact resistance, and handling stability. Rolling resistance and tread deformation are particularly prominent issues in their application scenarios. Using the aforementioned tread base compound can effectively leverage the performance advantages of the tread base compound, reduce fatigue heat generation, and improve tire life. It can also be applied to other tires with similar performance requirements.

[0028] The present invention will be further described below with reference to the embodiments.

[0029] Example 1: Method for determining the amount of bio-based silica in the tread base compound The basic formulation includes the following components by weight: 100 parts STR20 natural rubber, 32 parts N330 high abrasion-resistant furnace black, 15 parts 175MP silica, 3 parts Si-69 silane coupling agent, 3.5 parts zinc oxide, 2 parts stearic acid, 2.75 parts antioxidant, 1 part SL6905L tear-resistant resin, 1.9 parts accelerator NS, and 1 part sulfur S.

[0030] Formula A comprises the following components in parts by weight: 100 parts STR20 natural rubber, 21.4 parts N330 high abrasion-resistant furnace black, 10.6 parts LH-3 easily dispersible bio-based silica, 15 parts 175MP silica, 3 parts Si-69 silane coupling agent, 3.5 parts zinc oxide, 2 parts stearic acid, 2.75 parts antioxidant, 1 part SL6905L tear-resistant resin, 1.9 parts accelerator NS, and 1 part sulfur S.

[0031] Formula B comprises the following components in parts by weight: 100 parts STR20 natural rubber, 11 parts N330 high abrasion-resistant furnace black, 21 parts LH-3 easily dispersible bio-based silica, 15 parts 175MP silica, 3 parts Si-69 silane coupling agent, 3.5 parts zinc oxide, 2 parts stearic acid, 2.75 parts antioxidant, 1 part SL6905L tear-resistant resin, 1.9 parts accelerator NS, and 1 part sulfur S.

[0032] Formula C comprises the following components in parts by weight: 100 parts STR20 natural rubber, 32 parts LH-3 easily dispersible bio-based silica, 15 parts 175MP silica, 3 parts Si-69 silane coupling agent, 3.5 parts zinc oxide, 2 parts stearic acid, 2.75 parts antioxidant, 1 part SL6905L tear-resistant resin, 1.9 parts accelerator NS, and 1 part sulfur S.

[0033] Preparation methods include: S1. A shear-type internal mixer GK400 is used to produce the first-stage masterbatch. The top jack pressure is set to 0.5 MPa, and the water temperature in the three zones of the internal mixer is set to 35±5℃. STR20 natural rubber, N330 high abrasion-resistant furnace black, LH-3 easily dispersible bio-based silica, zinc oxide, stearic acid, antioxidant, and SL6905L tear-resistant resin are added to the internal mixer in one batch. The rotor speed is set to 50 rpm, and the mixture is mixed for 40 seconds until the rubber compound temperature reaches 120±5℃. A second top jack pressure is applied: the rotor speed is set to 45 rpm, and the mixture is mixed for 25 seconds until the rubber compound temperature reaches 145±5℃. A third top jack pressure is applied: the rotor speed is set to 35 rpm, and the mixture is mixed for 25 seconds until the rubber compound temperature reaches 160±5℃ before discharge, obtaining the first-stage masterbatch. S2. The second-stage masterbatch is prepared using a shear-type internal mixer GK400. The top jack pressure is set to 0.5 MPa, and the water temperature in the third zone of the internal mixer is set to 35±5℃. The first-stage masterbatch, 175 MPa silica, and Si-69 silane coupling agent are added at once. The rotor speed is set to 40 rpm, and the mixture is mixed for 40 seconds until the rubber compound temperature reaches 120±5℃. The top jack is then cleaned and pressed again: the rotor speed is set to 35 rpm, and the mixture is mixed for 20 seconds until the rubber compound temperature reaches 145±5℃. The top jack is raised and held for 10 seconds, and then the top jack is pressed again: the rotor speed is set to 30 rpm. The mixture is then mixed until the rubber compound temperature reaches 155±5℃, and the rubber compound is discharged to obtain the second-stage masterbatch. S3. Use a shear-type internal mixer GK255 to produce the three-stage final compound. Set the top jack pressure to 0.45MPa and the water temperature in the three zones of the internal mixer to 30±5℃. Add the second-stage masterbatch, accelerator NS and sulfur S at once, and mix for 30s with the top jack pressed once. Then mix for 30s with the top jack pressed twice. Then mix for another 30s until the compound temperature reaches 100±5℃ and then discharge the compound.

[0034] The properties of the rubber compounds prepared according to the basic formulation, formulation A, formulation B, and formulation C were tested: The tensile stress-stress properties of vulcanized rubber compounds were tested according to GB / T 528 standard. The international hardness properties of vulcanized rubber were tested according to GB / T 6031 standard. The right-angle tear resistance (without nick) of vulcanized rubber was tested according to GB / T 529 standard. The density properties of vulcanized rubber were tested according to standard GB / T 533. The Mooney viscosity of uncured rubber shall be tested according to GB / T 1232.1; The Mooney stress relaxation properties of uncured rubber were tested according to GB / T 1232.4 standard.

[0035] Rubber vulcanization properties (MDR) were tested according to GB / T 9869 standard. According to GB / T 9870[1].1, the dynamic performance loss tangent angle (RPA(TanD)) of vulcanized rubber was tested. According to GB / T 1687.3, the temperature rise and fatigue resistance of vulcanized rubber in the flexural test are tested (using the constant strain compression test method therein). The performance of vulcanized rubber in hot air aging and heat resistance tests was tested according to GB / T 3512 standard. The results are shown in Table 1.

[0036] Table 1

[0037] In the table, “ML(1+4)100℃” refers to Mooney viscosity. The test method includes: using a large rotor at 100℃, preheating for 1 minute, and then testing within a time range of 4 minutes.

[0038] It can be seen that, compared with the first basic formulation, formulations A through C, by partially or completely replacing the high abrasion-resistant furnace black with a set amount of LH-3 easily dispersible bio-based silica, increase the tensile strength and elongation at break of the rubber compound by about 5%; reduce the tensile stress at a given elongation by about 10%; slightly reduce the tear strength; significantly reduce compression heat by about 20%; reduce compression set by about 43%; reduce Mooney viscosity by about 5%; improve Mooney scorch by 10%; and reduce the loss factor TanD by 30%. By using LH-3 easily dispersible bio-based silica, the compression fatigue heat and permanent deformation of the rubber compound are significantly improved, and the rolling resistance is improved; the Mooney viscosity is reduced, the mixing time is shortened, and the production energy consumption is reduced. Bio-based silica LH-3 can replace up to 20 parts of high abrasion-resistant furnace black, effectively reducing fatigue heat generation while ensuring the overall performance of the rubber compound.

[0039] Example 2: Method for determining the composition of the base rubber compound in the tread. Formula D is defined as comprising the following components in parts by weight: 100 parts of STR20 natural rubber, 21.4 parts of N330 high abrasion-resistant furnace black, 10.6 parts of LH-3 easily dispersible bio-based silica, 15 parts of 175MP silica, 3 parts of Si-69 silane coupling agent, 3.5 parts of zinc oxide, 2 parts of stearic acid, 2.75 parts of antioxidant, 1 part of SL6905L tear-resistant resin, 1.9 parts of accelerator NS, 1 part of sulfur S, and 0.5 parts of zinc dithiophosphate crosslinking agent (AP9).

[0040] Formula E is defined as comprising the following components in parts by weight: 100 parts of STR20 natural rubber, 11 parts of N330 high abrasion-resistant furnace black, 21 parts of LH-3 easily dispersible bio-based silica, 15 parts of 175MP silica, 3 parts of Si-69 silane coupling agent, 3.5 parts of zinc oxide, 2 parts of stearic acid, 2.75 parts of antioxidant, 1 part of SL6905L tear-resistant resin, 1.9 parts of accelerator NS, 1 part of sulfur S, and 0.5 parts of zinc dithiophosphate crosslinking agent (AP9).

[0041] Formula F is defined as the following components in parts by weight: 100 parts of STR20 natural rubber, 21.4 parts of N330 high abrasion-resistant furnace black, 10.6 parts of LH-3 easily dispersible bio-based silica, 15 parts of 175MP silica, 3 parts of Si-69 silane coupling agent, 1 part of modified itaconic acid additive (kinge200 multifunctional additive), 3.5 parts of zinc oxide, 2 parts of stearic acid, 2.75 parts of antioxidant, 1 part of SL6905L tear-resistant resin, 1.9 parts of accelerator NS, 1 part of sulfur S, and 0.5 parts of zinc dithiophosphate crosslinking agent (AP9).

[0042] Formula G is defined as comprising the following components in parts by weight: 100 parts of STR20 natural rubber, 11 parts of N330 high abrasion-resistant furnace black, 21 parts of LH-3 easily dispersible bio-based silica, 15 parts of 175MP silica, 3 parts of Si-69 silane coupling agent, 1 part of modified itaconic acid additive (kinge200 multifunctional additive), 3.5 parts of zinc oxide, 2 parts of stearic acid, 2.75 parts of antioxidant, 1 part of SL6905L tear-resistant resin, 1.9 parts of accelerator NS, 1 part of sulfur S, and 0.5 parts of zinc dithiophosphate crosslinking agent (AP9).

[0043] The preparation method differs from that in Example 1 in that a modified itaconic acid additive is added in S1, and a zinc dithiophosphate crosslinking agent (AP9) is added in S3; the other steps of the preparation method are the same as those in Example 1.

[0044] The performance of the rubber compounds prepared by the basic formulation, formulation D, formulation E, formulation F and formulation G was tested according to the method of Example 1. The results are shown in Table 2. The basic formulation in Table 2 was tested in the same batch as the other formulations in Table 2. The results deviated due to the different testing time and batch compared with the basic formulation in Table 1.

[0045] Table 2

[0046] It can be seen that, with the addition of bio-based silica, the crosslinking agent AP9 can effectively improve the tensile stress at a given elongation, tensile strength, prolong Mooney scorch, and improve Mooney stress relaxation. Kinge200 multifunctional additive can improve the dispersibility of the rubber compound filler system, significantly increase the tensile strength and elongation at break, and significantly improve compression heat generation and compression set. When applied to the tread base compound of heavy-duty all-steel radial tires, higher Mooney stress relaxation α and k values ​​indicate better compound flow properties and better dimensional stability of the extruded semi-finished product; lower compound loss factor TanD values ​​indicate lower compound flow resistance coefficients and better fatigue resistance.

[0047] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A tread base compound, characterized in that it comprises: The following components are present in parts by weight: 100 parts natural rubber, 10-25 parts high abrasion furnace black, 10-25 parts bio-based silica, 10-20 parts silica, 2-5 parts silane coupling agent, 0.5-1.5 parts modified itaconic acid additive, 3-5 parts zinc oxide, 1-3 parts stearic acid; 2-4 parts antioxidant; 0.5-2 parts tear-resistant resin, 1-3 parts accelerator; 0.5-1.5 parts sulfur powder; 0.5-1.5 parts zinc dithiophosphate crosslinking agent.

2. The tread base rubber compound as described in claim 1, characterized in that, The natural rubber includes one or more of STR20, SMR20 and SVR3L.

3. The tread base rubber compound as described in claim 1, characterized in that, The high abrasion-resistant carbon black includes one or more of N330 and N326; Alternatively, the bio-based silica may include easily dispersible bio-based silica made from marine diatomaceous earth; Alternatively, the silica may include one or more of precipitated silica, hydrated water, and silica.

4. The tread base rubber compound as described in claim 3, characterized in that, The silane coupling agent includes one or more of Si-69, SCA-S75X and SCA-MS89E; Alternatively, modified itaconic acid additives are prepared by surface modification of itaconic acid.

5. The tread base rubber compound as described in claim 1, characterized in that, The tear-resistant resin includes one or more of petroleum resin SL6905L, RT260, and terpene phenolic resin; Alternatively, the accelerator may include one or more of accelerators NS, CZ, and DM.

6. A method for preparing the tread base compound as described in any one of claims 1-5, characterized in that, Including the following steps: S1. Natural rubber, high abrasion-resistant furnace black, bio-based silica, modified itaconic acid additive, zinc oxide, stearic acid, antioxidant and tear-resistant resin are mixed and compounded at 115~165℃ to obtain a first-stage masterbatch. S2. Mix the first-stage masterbatch, silica and silane coupling agent, and knead at 115~158℃ to obtain the second-stage masterbatch. S3. Mix the second-stage masterbatch, accelerator, sulfur powder and zinc dithiophosphate crosslinking agent, and knead at 98-105℃ to obtain the tread base compound.

7. The method for preparing the tread base compound as described in claim 6, characterized in that, In S1, the mixture is stirred at 40-50 rpm for 30-40 seconds until the rubber compound temperature reaches 115-125℃; then the top bolt is pressed on for the second time, and the mixture is stirred at 35-45 rpm for 15-25 seconds until the rubber compound temperature reaches 140-150℃; finally, the top bolt is pressed on for the third time, and the mixture is stirred at 35-45 rpm for 15-25 seconds until the rubber compound temperature reaches 155-165℃, and then the rubber is discharged.

8. The method for preparing the tire tread rubber composition according to claim 6, characterized in that, in S2, the mixing time is 20-25s at a speed of 35-45 rpm until the rubber compound temperature is 115-125℃; the top plug is pressed on a second time, and the mixing time is 15-25s at a speed of 35-45 rpm until the rubber compound temperature is 140-150℃; the top plug is pressed on a third time, and the mixing time is 30-35 rpm until the rubber compound temperature is 153-158℃, and the rubber is discharged.

9. The method for preparing the tire tread rubber composition according to claim 6, characterized in that, in S3, the rubber is mixed at a speed of 15~25 rpm for 25~35 s; mixed again under the top plug for 25~35 s; mixed again under the top plug for 20~30 s until the rubber temperature is 98~105℃, and then discharged.

10. A heavy-duty all-steel radial tire, characterized in that, The tread base rubber uses the tread base rubber compound as described in any one of claims 1-5.

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