High-vinyl zinc-oxide-free tire tread rubber composition and preparation method thereof

Abstract

The invention relates to the technical field of tire rubber manufacturing, and discloses a high-vinyl zinc-oxide-free tire tread rubber composition and a preparation method thereof.The high-vinyl zinc-oxide-free tire tread rubber composition is prepared from, by weight, 60-90 parts of solution polymerized styrene-butadiene rubber, 10-40 parts of natural rubber, 0.1-0.6 part of a white carbon black dispersing agent DST-100, 0.1-0.6 part of an anti-aging agent, 0.1-0.6 part of an anti-aging agent, 0.1-0.6 part of an anti-aging agent, 0.1-0.6 part of an anti-aging agent, 0.1-0.6 part of an anti-aging agent, 0.1-0.6 part of The composition comprises the following components in parts by weight: 1.0-2.0 parts of a silane coupling agent, 0.05-0.25 part of a scorch retarder, 1.0-2.0 parts of sulfur, 1.0-4.0 parts of an accelerant and 2.0-10.0 parts of a silane coupling agent. The rubber composition adopts a high-vinyl zinc-oxide-free rubber reaction system, in the system, the vinyl content of solution polymerized styrene-butadiene rubber is greater than or equal to 55wt%, and a white carbon black dispersing agent DST-100 contains 5-15wt% of zinc element. According to the system, the white carbon black dispersing agent DST-100 is adopted to replace zinc oxide, dependence on Zn < 2 + > is remarkably reduced, release of Zn < 2 + > in tread particles is reduced, and economic benefits are improved.

Description

Technical Field

[0001] The invention relates to the technical field of tire rubber manufacturing, in particular to a high-vinyl zinc oxide-free tire tread rubber composition and a preparation method thereof. Background Art

[0002] The "activation system" composed of zinc oxide and stearic acid is a common system in tire rubber vulcanization. This "activation system" is one of the core technologies of the rubber vulcanization process, especially in tire tread rubber, which plays a decisive role in improving the vulcanization efficiency and the overall performance of the rubber compound. The synergistic effect of zinc oxide and stearic acid is essentially to generate a highly active intermediate (zinc stearate) through chemical modification, thereby accelerating the decomposition of sulfur, promoting the reaction of sulfur free radicals with rubber, and optimizing the cross-linking network structure. Zinc stearate is an organic metal salt with better dispersibility in the rubber matrix, and the zinc ion (Zn 2+ ) has a stronger ability to bind with sulfur (S), providing active centers for subsequent vulcanization reactions. 17 H 35 COO)2] is made of zinc oxide (ZnO, basic oxide) and stearic acid (C 17 H 35 COOH, fatty acid) is obtained by neutralization reaction.

[0003] In the traditional vulcanization system, sulfur needs to be decomposed into active sulfur free radicals (such as S8→8S·) before it can react with the rubber molecular chain, but the activation energy of this process is high. Zinc stearate can react with the rubber molecular chain through coordination (Zn 2+ The formation of coordination compounds with sulfur molecules weakens the bond energy of SS bonds and promotes the decomposition of sulfur into active sulfur free radicals) and polar effects (the polar groups of zinc stearate interact with sulfur molecules, changing their molecular arrangement and making them easier to break) reduce the reaction energy barrier of the process. In addition, zinc stearate as a Lewis acid (Zn 2+ Provide empty orbitals), can form temporary coordination with the double bonds in the rubber molecular chain (such as C=C bonds of styrene-butadiene rubber and natural rubber), reduce the electron cloud density of the double bonds, make it easier to react with sulfur free radicals, and accelerate the formation of a cross-linked network.

[0004] In terms of optimizing the cross-linked network structure of rubber, zinc stearate can regulate the cross-linking bond type and improve the uniformity of cross-linking density. Specifically, zinc stearate can reduce the polysulfide bonds (-S nThe generation of polythio groups (n≥4) promotes the formation of single sulfur bonds (-S-) and double sulfur bonds (-S2-). The bond energy of single sulfur bonds and double sulfur bonds is higher and the stability is stronger, which can improve the heat resistance and aging resistance of vulcanized rubber. However, the polythio bond is easy to break, which can cause the rubber to harden or crack. Secondly, as a vulcanization activation center, zinc stearate can make the vulcanization reaction more uniformly in the rubber matrix, avoiding local crosslinking density being too high or too low, thereby improving the mechanical properties (such as tensile strength and elasticity) of the vulcanized rubber.

[0005] However, life cycle assessment studies have shown that tire wear is an important source of zinc in the environment. Zinc is released into the environment in the form of free particles with tire wear, and European Union studies have shown that tire wear contributes 30-50% of the zinc concentration in urban surface water. Excessive zinc can potentially harm soil microbial communities, aquatic organisms, and other organisms, affecting the balance and function of the ecosystem. For example, for aquatic organisms, high concentrations of zinc can interfere with their physiological processes such as respiration and reproduction, posing a threat to their survival and reproduction. Therefore, the European Union limits Zn≤0.95kg / t tread.

[0006] A green and environmentally friendly tread rubber disclosed in Chinese invention patent (publication number: CN111218038A, publication date: June 2, 2020) includes the following weight parts of raw materials: 40-60 parts of tobacco sheet rubber, 30-40 parts of butadiene rubber, 20-30 parts of solution polymerized butadiene rubber, 5-6 parts of tread rubber powder are put into an open mill to obtain plasticized rubber; the plasticized rubber is mixed with 20-30 parts of carbon black, 10-15 parts of white carbon black, 0.5-1.0 parts of white carbon black dispersant, 1.5-2.0 parts of silane coupling agent, 8-12 parts of titanium white powder, 1.0-1.5 parts of stearic acid, 0.2-0.3 parts of anti-scorching agent, 2-3 parts of antioxidant, 1.5-2.0 parts of microcrystalline wax, 0.1-0.5 parts of anti-reversion agent, 1.5-2.0 parts of polyvinyl alcohol, and 1.0-3.0 parts of triisopropanolamine are put into a mixing machine for mixing; insoluble sulfur is added, and the rubber is discharged after 10 minutes of continuous mixing. The formula provided by the invention does not add zinc oxide, but the addition of stearic acid alone cannot form a complete activation effect. The lack of effective activators can significantly reduce the vulcanization efficiency, mechanical properties, filler dispersion, and thermal stability. Nano-zinc oxide or organic zinc salt has high unit price and poor batch dispersity; the shell of coated zinc oxide has large melting point difference, poor scorching repeatability, and still releases zinc in the form of zinc oxide, with limited environmental benefits. Therefore, it is urgent to find a suitable material to replace zinc oxide to meet the environmental requirements of the European Union. SUMMARY

[0007] The present application provides a high ethylene-based zinc-free tire tread rubber composition and a preparation method thereof to overcome the shortcomings of the prior art. The system uses white carbon black dispersant DST-100 instead of zinc oxide, and the Zn 2+The dependence on Zn in tread particles is significantly reduced. 2+ and improve economic benefits.

[0008] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions:

[0009] A high-vinyl zinc oxide-free tire tread rubber composition is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber:

[0010] 60-90 parts by weight of solution-polymerized styrene-butadiene rubber,

[0011] 10 to 40 parts by weight of natural rubber,

[0012] 0.1 to 0.6 parts by weight of white carbon black dispersant DST-100,

[0013] 0.05 to 0.25 parts by weight of scorch retarder,

[0014] 1.0 to 2.0 parts by weight of sulfur,

[0015] 1.0 to 4.0 parts by weight of accelerator,

[0016] 2.0-10.0 parts by weight of silane coupling agent;

[0017] The vinyl content of the solution-polymerized styrene-butadiene rubber is ≥55wt%;

[0018] The white carbon black dispersant DST-100 contains 5 to 15 wt% of zinc.

[0019] Preferably, the rubber composition is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber:

[0020] 70-90 parts by weight of solution-polymerized styrene-butadiene rubber,

[0021] 10 to 30 parts by weight of natural rubber,

[0022] 50 to 80 parts by weight of white carbon black,

[0023] 0.5 to 10 parts by weight of carbon black,

[0024] 0.2 to 0.6 parts by weight of white carbon black dispersant DST-100,

[0025] 0.05-0.25 parts by weight of scorch retarder PVI,

[0026] 1.0 to 3.0 parts by weight of stearic acid,

[0027] 1.0 to 2.0 parts by weight of sulfur,

[0028] Accelerator CBS 1.0-2.0 parts by weight,

[0029] Accelerator TBzTD 0.2-0.6 parts by weight,

[0030] 1.0 to 5.0 parts by weight of antioxidant,

[0031] 4.0 to 8.0 parts by weight of silane coupling agent

[0032] Preferably, the vinyl content of the solution-polymerized styrene-butadiene rubber is 58-65 wt%.

[0033] Preferably, the silane coupling agent is Si-69.

[0034] Preferably, the antioxidant is 6PPD.

[0035] Preferably, the sulfur-extended oil is 5 to 15 wt%.

[0036] Furthermore, the present invention also provides a method for preparing a high-vinyl zinc oxide-free tire tread rubber composition, comprising the following steps:

[0037] 1) Mixing stage: using an internal mixer to pre-mix solution-polymerized styrene-butadiene rubber, natural rubber, white carbon black, carbon black, and chemical additives, wherein the chemical additives do not include antioxidants, scorch retarders, sulfur, and accelerators, and mixing at 150-160° C. to obtain a masterbatch A;

[0038] 2) Mixing stage 2: Use an internal mixer to mix the masterbatch A, and exhaust at 120-130°C for 20-40 seconds to obtain masterbatch B;

[0039] 3) Final mixing stage: using an internal mixer to mix the masterbatch B, antioxidant, anti-scorch agent, sulfur and accelerator at a mixing temperature of 90-100°C, discharging the sheet at 80-90°C, and standing for 24 hours to obtain a tread rubber composition.

[0040] Preferably, the tread rubber composition has a vulcanization temperature of 150-170° C. and a vulcanization time of 10-20 minutes.

[0041] Preferably, the tread rubber composition has a vulcanization temperature of 160° C. and a vulcanization time of 15 minutes.

[0042] The present invention provides a high vinyl zinc oxide-free tire tread rubber composition. The rubber composition adopts a high vinyl zinc oxide-free rubber reaction system. In the system, the vinyl (Vinyl, -CH=CH2) content of the solution-polymerized styrene-butadiene rubber must reach a level of ≥55wt%. When the vinyl content in the rubber molecular chain is ≥55wt%, the addition reaction of sulfur radicals to its double bonds becomes the dominant vulcanization path, making the system more sensitive to Zn2+ The dependence on the reaction of vinyl double bonds (-CH=CH2) is significantly reduced. This is because the reaction activity of vinyl double bonds (-CH=CH2) is higher than that of ordinary carbon-carbon double bonds (such as the double bonds in the rubber main chain). The vinyl groups on the rubber molecular chain in the high vinyl system form dense reaction sites. The sulfur free radicals can be directly and quickly added to the vinyl groups. The activation energy of this reaction is lower, and the rate constant is 1 to 2 orders of magnitude higher than that of the traditional path. It becomes the dominant reaction of vulcanization, thereby reducing the dependence on Zn 2+ However, completely removing Zn 2+ It will cause the rubber to burn too quickly (ts2<2min) and the modulus loss is serious (>25%). Therefore, the present invention uses white carbon black dispersant DST-100 (containing 5~15wt% of zinc element) to replace zinc oxide. Zinc is "locked" on the surface of SiO2, and only a trace amount of Zn 2+ The silica dispersant DST-100 provides both Zn 2+ , ensuring Zn ≤ 0.95kg / t tread; it also helps disperse silica in the rubber matrix, preventing agglomeration and significantly reducing the performance of the rubber composition. From an economic perspective, DST-100 offers cost advantages. A rough estimate shows that using DST-100 instead of zinc oxide saves 25-40 yuan per ton of rubber. DETAILED DESCRIPTION

[0043] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts are within the scope of protection of the present invention.

[0044] The tire tread rubber of the present application avoids the classic system of rubber vulcanization: the combination of zinc oxide and stearic acid. The materials in the formula are not particularly limited and are commonly available materials.

[0045] There are no particular limitations on carbon black, and commonly used carbon blacks can be used. Examples include furnace black, thermal black, acetylene black, and Ketjen black, but pyrolysis black is not considered. Of these, furnace black is preferred from the perspective of further improving the mechanical strength of the rubber composition. These can be used alone or in combination of two or more. Furthermore, to further enhance compatibility with the rubber component, the surface may be subjected to an organic treatment.

[0046] As white carbon black, it means a silica-silicic acid filling material, and does not only mean silica in a narrow sense. It is not particularly limited and can be appropriately selected from existing materials used as reinforcing filling materials. For example, wet silica (hydrous silicic acid), dry silica (anhydrous silica) and the like can be cited. Among these, wet silica is preferred from the viewpoint of further improving processability, wet-slip resistance and wear resistance. These can be used alone or in combination of two or more. In addition, in order to further improve the affinity with the rubber component, a treatment layer formed by a surface treatment agent is preferably formed on the surface.

[0047] The antioxidant is not particularly limited and commonly used antioxidants can be used, including amines, phenols, and heterocyclic antioxidants, which can be used alone or in combination of two or more.

[0048] Examples of amine antioxidants include N-phenyl-N'-isopropyl-p-phenylenediamine (4010NA), N-phenyl-N'-sec-butyl-p-phenylenediamine (4020), N-1,3-dimethylbutyl-N'-phenyl-p-phenylenediamine (6PPD), N-cyclohexyl-N'-phenyl-p-phenylenediamine (CPPD), a condensate of p-phenylenediamine and diphenylamine (H-8), a condensate of p-phenylenediamine and acetone (AP), 4-aminodiphenylamine (RT Base), N-(1-methylheptyl)-N'-phenyl-p-phenylenediamine (7PPD), N-(1-methylheptyl)-N'-(4-chlorophenyl)-p-phenylenediamine (7PCPD), and N-(1-methylheptyl)-N'-(3-chlorophenyl)-p-phenylenediamine (7MCPD).

[0049] Examples of phenolic antioxidants include 2,6-di-tert-butyl-4-methylphenol (BHT), pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (1010), tris[2,4-di-tert-butylphenyl]phosphite (168), 2-(2-hydroxy-5-methylphenyl)benzotriazole (UV-P), and 2-(2-hydroxy-4-methoxyphenyl)benzotriazole (UV-9).

[0050] Examples of heterocyclic antioxidants include 2-mercaptobenzimidazole (MBI), 2-mercaptobenzimidazole zinc salt (MBZ), 2-(2-hydroxyphenyl)benzimidazole (HPBI), 2-(2-aminophenyl)benzimidazole (APBI), 2-(2-methoxyphenyl)benzimidazole (MPBI), 2-(2-dodecyloxyphenyl)benzimidazole (DDPI), 2-(2-benzyloxyphenyl)benzimidazole (BOPI), and 2-(2-phenoxyphenyl)benzimidazole (POPI).

[0051] Among them, the antioxidant 6PPD is preferred.

[0052] The silane coupling agent is not particularly limited, and examples thereof include sulfide-based, polysulfide-based, thioester-based, thiol-based, olefin-based, epoxy-based, amino-based, and alkyl-based silane coupling agents. These may be used alone or in combination of two or more. Among these, sulfide-based and amino-based silane coupling agents are preferred.

[0053] Examples of the sulfide-based silane coupling agent include bis(3-triethoxysilylpropyl)tetrasulfide, bis(3-trimethoxysilylpropyl)tetrasulfide, bis(3-methyldimethoxysilylpropyl)tetrasulfide, bis(2-triethoxysilylethyl)tetrasulfide, bis(3-triethoxysilylpropyl)disulfide, bis(3-trimethoxysilylpropyl)disulfide, bis(3-methyldimethoxysilylpropyl)disulfide, bis(2-triethoxysilylethyl)disulfide, bis(3-triethoxysilylpropyl)trisulfide, bis(3-trimethoxysilylpropyl)trisulfide, bis(3-methyldimethoxysilylpropyl)trisulfide, Bis(3-monoethoxydimethylsilylpropyl)trisulfide, bis(2-triethoxysilylethyl)trisulfide, bis(3-monoethoxydimethylsilylpropyl)tetrasulfide, bis(3-monoethoxydimethylsilylpropyl)trisulfide, bis(3-monoethoxydimethylsilylpropyl)disulfide, bis(3-monomethoxydimethylsilylpropyl)tetrasulfide, bis(3-monomethoxydimethylsilylpropyl)trisulfide, bis(3-monomethoxydimethylsilylpropyl)disulfide, bis(2-monoethoxydimethylsilylethyl)tetrasulfide, bis(2-monoethoxydimethylsilylethyl)trisulfide, bis(2-monoethoxydimethylsilylethyl)disulfide, etc. Among these, bis(3-triethoxysilylpropyl)tetrasulfide is preferred.

[0054] Examples of the thioester-based silane coupling agent include 3-hexanoylthiopropyltriethoxysilane, 3-octanoylthiopropyltriethoxysilane, 3-decanoylthiopropyltriethoxysilane, 3-lauroylthiopropyltriethoxysilane, 2-hexanoylthioethyltriethoxysilane, 2-octanoylthioethyltriethoxysilane, 2-decanoylthioethyltriethoxysilane, 2-lauroylthioethyl ... 3-Hexanoylthiopropyltrimethoxysilane, 3-octanoylthiopropyltrimethoxysilane, 3-decanoylthiopropyltrimethoxysilane, 3-lauroylthiopropyltrimethoxysilane, 2-hexanoylthioethyltrimethoxysilane, 2-octanoylthioethyltrimethoxysilane, 2-decanoylthioethyltrimethoxysilane, 2-lauroylthioethyltrimethoxysilane, etc.

[0055] Examples of the thiol-based silane coupling agent include 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, and 3-mercaptopropylmethyldimethoxysilane.

[0056] Examples of the olefin-based silane coupling agent include dimethoxymethylvinylsilane, vinyltrimethoxysilane, dimethylethoxyvinylsilane, diethoxymethylvinylsilane, triethoxyvinylsilane, vinyltri(2-methoxyethoxy)silane, allyltrimethoxysilane, allyltriethoxysilane, p-styryltrimethoxysilane, 3-(methoxydimethoxydimethylsilyl)propyl acrylate, 3-(trimethoxysilyl)propyl acrylate, 3-[dimethoxy(methyl)silyl]propyl methacrylate, 3-(trimethoxysilyl)propyl methacrylate, 3-[dimethoxy(methyl)silyl]propyl methacrylate, 3-(triethoxysilyl)propyl methacrylate, and 3-[tris(trimethylsiloxy)silyl]propyl methacrylate.

[0057] Examples of epoxy-based silane coupling agents include 3-glycidoxypropyl(dimethoxy)methylsilane, 3-glycidoxypropyltrimethoxysilane, diethoxy(3-glycidoxypropyl)methylsilane, triethoxy(3-glycidoxypropyl)silane, and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane.

[0058] Examples of amino-based silane coupling agents include N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-ethoxysilyl-N-(1,3-dimethylbutylene)propylamine, N-phenyl-3-aminopropyltrimethoxysilane, and N-(vinylbenzyl)-2-aminoethyl-3-aminopropyltrimethoxysilane. Among these, 3-aminopropyltriethoxysilane is preferred.

[0059] Examples of the alkyl-based silane coupling agent include methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, n-propyltrimethoxysilane, isobutyltrimethoxysilane, isobutyltriethoxysilane, n-hexyltrimethoxysilane, n-hexyltriethoxysilane, cyclohexylmethyldimethoxysilane, n-octyltriethoxysilane, and n-decyltrimethoxysilane.

[0060] Among them, bis-(γ-triethoxysilylpropyl)tetrasulfide is preferred.

[0061] The formulations of the embodiments and comparative examples are shown in Table 1.

[0062] Table 1

[0063]

[0064]

[0065] The footnotes to Table 1 are as follows:

[0066] *1: Solution polymerized styrene butadiene rubber HPR355, styrene accounts for 25% of the total polymer weight, and vinyl accounts for 57% of the total butadiene weight. Product of JSR Corporation of Japan

[0067] *2: Solution styrene butadiene rubber SL553, styrene accounts for 10% of the total polymer weight, vinyl accounts for 40% of the total butadiene weight, product of JSR Corporation

[0068] *3: Zinc-containing silica dispersant DST-100, a product of Wuxi Dongcai Technology

[0069] *4: Does not contain zinc silica dispersant SPA, Weihai Long Yinda Chemical products

[0070] All reagents in the formula are commercially available, and the two solution-polymerized styrene-butadiene rubbers can also be of other brands.

[0071] Tread rubber composition mixing method steps:

[0072] 1) Mixing stage: using an internal mixer to pre-mix solution-polymerized styrene-butadiene rubber, natural rubber, white carbon black, carbon black, and chemical additives, wherein the chemical additives do not include antioxidants, scorch retarder, sulfur, and accelerators, and mixing at 150-155° C. to obtain a masterbatch A;

[0073] 2) Mixing stage 2: Use internal mixer to mix, continue mixing masterbatch A, exhaust at 125℃ for 30s to obtain masterbatch B;

[0074] 3) Final mixing stage: Use an internal mixer to mix the masterbatch B, antioxidant, anti-scorch agent, sulfur, and accelerator at a mixing temperature of 95°C to 85°C, and let it stand for 24 hours to obtain a tread rubber composition.

[0075] The tread rubber composition was vulcanized at a temperature of 160° C. for 15 minutes.

[0076] The tread rubber compositions of the embodiments and comparative examples were subjected to performance tests using the following test methods:

[0077] 1) ts2: See ISO 6502MDR, 160°C x 15 min;

[0078] 2) M100, M300, TS (tensile strength): See ISO 37-2023, using standard ring specimens.

[0079] 3) Tear strength: Refer to ISO 34-1 (Die C), tested at room temperature.

[0080] 4) Dynamic loss tanδ: ARESDMA test was used. Test conditions: 10 Hz, -20 to 80°C, with the 60°C point being used.

[0081] 5) Free zinc precipitation: XRF-SEM on wear particles.

[0082] The test results are shown in Table 1.

[0083] Observing Table 1, it can be seen that the examples all use zinc-containing white carbon black dispersant DST-100 instead of zinc oxide in the high vinyl rubber system, and the ts2 of the obtained rubber composition is ≥3min. Although the performance has declined, it is acceptable; and Example 3 is the best example, and the performance loss of the rubber composition obtained by this formula is negligible. It can be seen from Example 1 and Comparative Example 2 that when zinc stearate is used in equal amounts to replace zinc oxide, although the free zinc content is close to the standard index, the performance of the rubber composition is seriously reduced and burns too quickly. It can be seen from Example 1 and Comparative Example 3 that complete removal of zinc will cause too fast burning and a serious decline in the performance of the rubber composition. It can be seen from Example 1 and Comparative Example 4 that if the vinyl content in the rubber is less than 55wt%, it will cause too fast burning and a serious decline in the performance of the rubber composition. ,

[0084] The above is a description of the embodiments of the present invention. The above description of the disclosed embodiments will enable professionals in the field to implement or use the present invention. Various modifications to these embodiments will be apparent to professionals in the field. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but should conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A high vinyl zinc oxide-free tire tread rubber composition, characterized in that: The rubber composition is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber: 60-90 parts by weight of solution-polymerized styrene-butadiene rubber, 10-40 parts by weight of natural rubber, 0.1~0.6 parts by weight of white carbon black dispersant DST-100, 0.05-0.25 parts by weight of scorch retarder PVI, 1.0-2.0 parts by weight of sulfur, Accelerator CBS 1.0~2.0 parts by weight, Accelerator TBzTD 0.2~1.0 parts by weight, 2.0-10.0 parts by weight of silane coupling agent; The vinyl content of the solution-polymerized styrene-butadiene rubber is ≥55wt%; The white carbon black dispersant DST-100 contains 5 to 15 wt % of zinc.

2. The high vinyl zinc oxide-free tire tread rubber composition according to claim 1, characterized in that: The rubber composition is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber: 70-90 parts by weight of solution-polymerized styrene-butadiene rubber, 10-30 parts by weight of natural rubber, 50-80 parts by weight of white carbon black, 0.5-10 parts by weight of carbon black, 0.2~0.6 parts by weight of white carbon black dispersant DST-100, 0.5-0.25 parts by weight of scorch retarder PVI, 1.0 to 3.0 parts by weight of stearic acid, 0.3-0.8 parts by weight of zinc stearate, 1.0-2.0 parts by weight of sulfur, Accelerator CBS 1.0~2.0 parts by weight, Accelerator TBzTD 0.2~0.6 parts by weight, 1.0~5.0 parts by weight of antioxidant, 4.0-8.0 parts by weight of silane coupling agent 3. A high vinyl zinc oxide-free tire tread rubber composition according to claim 1 or 2, characterized in that: The solution-polymerized styrene-butadiene rubber has a vinyl content of 58-65 wt %.

4. A high vinyl zinc oxide-free tire tread rubber composition according to claim 1 or 2, characterized in that: The silane coupling agent is Si-69.

5. A high vinyl zinc oxide-free tire tread rubber composition according to claim 1 or 2, characterized in that: The sulfur-extended oil is 5-15 wt%.

6. A high vinyl zinc oxide-free tire tread rubber composition according to claim 1 or 2, characterized in that: The antioxidant is 6PPD.

7. The method for preparing a high-vinyl zinc oxide-free tire tread rubber composition according to any one of claims 1 to 6, characterized in that: The following steps are involved: 1) Mixing stage: using an internal mixer to pre-mix solution-polymerized styrene-butadiene rubber, natural rubber, white carbon black, carbon black, and chemical additives. The chemical additives here do not include antioxidants, sulfur, and accelerators. The mixing temperature is 125-155°C and the mixing time is 1-4 minutes to obtain a masterbatch. 2) Final mixing stage: an internal mixer is used to mix the masterbatch, antioxidant, sulfur and accelerator at a mixing temperature of 90-100°C, a mixing time of 1-2 minutes and a discharge temperature of 80-90°C to obtain a tread rubber composition.

8. The method for preparing a high-vinyl zinc oxide-free tire tread rubber composition according to claim 7, characterized in that: The vulcanization temperature of the tread rubber composition is 150-170° C., and the vulcanization time is 10-20 minutes.

9. The method for preparing a high vinyl zinc oxide-free tire tread rubber composition according to claim 7, characterized in that: The tread rubber composition has a vulcanization temperature of 160° C. and a vulcanization time of 15 minutes.

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