A low noise, low rolling resistance tire tread and method of making the same

Abstract

The application discloses a low-noise and low-rolling-resistance tire tread and a preparation method thereof, and relates to the technical field of tire production. The tire tread comprises a supporting layer and a multi-phase composite tread rubber. The multi-phase composite tread rubber comprises a continuous phase matrix, a two-phase structure white carbon black, functionalized multi-walled carbon nanotubes, a double silane coupling agent, dynamic crosslinking thermoplastic elastomer microparticles, zinc oxide, stearic acid, an antioxidant, an accelerator and sulfur. The tire tread can significantly reduce tire rolling resistance and driving noise while maintaining good wear resistance and mechanical strength.

Description

Technical Field

[0001] This invention relates to the field of tire manufacturing technology, specifically to a low-noise, low-rolling-resistance tire tread and its preparation method. Background Technology

[0002] With the development of the automotive industry and increasingly stringent environmental regulations, the market has placed higher demands on tire performance, especially low rolling resistance (which reduces fuel consumption and carbon emissions) and low noise (which improves driving comfort), which have become key indicators for high-performance tires. However, there is often a mutually restrictive relationship between tire performance characteristics such as rolling resistance, noise, and wear resistance (i.e., the "devil's triangle"), and traditional compounds and structures cannot simultaneously achieve optimization in multiple aspects.

[0003] In existing technologies, rolling resistance is usually reduced by using highly dispersed silica, solution-polymerized styrene-butadiene rubber, etc., or by changing the pattern design and adding elastomers to reduce noise. However, the effect of a single method is limited and often comes at the cost of sacrificing other properties. Summary of the Invention

[0004] The first technical problem to be solved by the present invention is to provide a tire tread with low noise and low rolling resistance, which significantly reduces tire rolling resistance and driving noise while maintaining good wear resistance and mechanical strength.

[0005] To solve the first technical problem mentioned above, the technical solution of the present invention is:

[0006] A low-noise, low-rolling-resistance tire tread, comprising a support layer and a multiphase composite tread compound;

[0007] The multiphase composite tread compound includes a continuous phase matrix, biphase silica, functionalized multi-walled carbon nanotubes, bissilane coupling agent, dynamically crosslinked thermoplastic elastomer microparticles, zinc oxide, stearic acid, antioxidant, accelerator, and sulfur.

[0008] Preferably, the weight ratio of the continuous phase matrix, biphase silica, functionalized multi-walled carbon nanotubes, dynamically cross-linked thermoplastic elastomer microparticles, zinc oxide, stearic acid, antioxidant, accelerator and sulfur in the multiphase composite tread rubber is 100:50-70:1-3:5-15:1.5-3.0:1-2:2-5:1.5-3.5:0.8-1.8;

[0009] The amount of bissilane coupling agent added is 6-10% w / w of the total weight of the two-phase silica.

[0010] Preferably, the continuous phase matrix comprises solution-polymerized styrene-butadiene rubber and neodymium-based cis-butadiene rubber, wherein the weight ratio of solution-polymerized styrene-butadiene rubber to neodymium-based cis-butadiene rubber is 60-80:20-40.

[0011] Preferably, the specific surface area of ​​the high-structure silica in the dual-phase silica is ≥175m² / g, the specific surface area of ​​the low-structure silica is ≤125m² / g, and the mass ratio of high-structure silica to low-structure silica is 7:3.

[0012] In the bissilane coupling agent, sulfur-containing silanes account for 70-85% w / w of the total silane content, and flexible long-chain silanes account for 15-30% w / w of the total silane content.

[0013] The dynamically cross-linked thermoplastic elastomer microparticles are EPDM / PP based and have a particle size of 1-5 μm;

[0014] The antioxidants include p-phenylenediamine antioxidants and quinoline antioxidants, with a weight ratio of p-phenylenediamine antioxidants to quinoline antioxidants of 1.5-3:0.5-2.

[0015] The accelerator includes a sulfenamide primary accelerator and a guanidine or thiuram secondary accelerator, with the weight ratio of the primary accelerator to the secondary accelerator being 1-2:0.5-1.5.

[0016] The supporting layer is composed of functionalized solution-polymerized styrene-butadiene rubber, high-vinyl solution-polymerized styrene-butadiene rubber, liquid isoprene rubber, graphene-coated hollow glass microspheres, chopped aramid fibers, carbon nanotube-grafted silica hybrid filler, dynamic covalent crosslinking agent, zinc oxide nanorods, 4,4'-bis(α,α-dimethylbenzyl)diphenylamine, 2-mercapto-4-methylbenzimidazole zinc salt, tetrabenzylthiuram disulfide, accelerator Si-69, and sulfur in a weight ratio of 40-50:30-40:10-15:15-25:5-10:10-15:1-3:3-5:1-1.5:0.5-1:0.3-0.6:1-2:0.8-1.2.

[0017] It also includes silane coupling agents, which are added at 5-8% w / w of the total weight of graphene-coated hollow glass microspheres and carbon nanotube-grafted silica hybrid fillers.

[0018] The method for preparing the support layer includes the following steps:

[0019] S1. Filler predispersion and functionalization

[0020] S1-1. Graphene-coated hollow glass microspheres and 1 / 2 of the amount of silane coupling agent are dry-mixed in a high-speed mixer at 80-100℃ and 1500-2000r / min for 10min to obtain pretreated graphene-coated hollow glass microspheres.

[0021] S1-2. The carbon nanotube-grafted silica hybrid filler and the remaining silane coupling agent were ultrasonically treated in an ethanol solution for 30 min, and then the solvent was evaporated to obtain the pretreated carbon nanotube-grafted silica hybrid filler.

[0022] S2. Segmented mixing of masterbatch

[0023] S2-1. First stage mixing: Functionalized solution-polymerized styrene-butadiene rubber, high-vinyl solution-polymerized styrene-butadiene rubber, and liquid isoprene rubber are added to an internal mixer and plasticized at 60-70℃ for 1 min. Pretreated graphene-coated hollow glass microspheres, pretreated carbon nanotube-grafted silica hybrid filler, zinc oxide nanorods, and 4,4'-bis(α,α-dimethylbenzyl)diphenylamine and 2-mercapto-4-methylbenzimidazole zinc salt are added and mixed at 130-145℃ for 4-5 min to ensure that the filler is fully dispersed and wetted. The first stage masterbatch is obtained by debinding.

[0024] S2-2. Two-stage mixing: Put the first-stage masterbatch back into the internal mixer, add the pretreated short-cut aramid fibers, mix at 100-110℃ and low rotor speed for 2-3 minutes, and then discharge the glue.

[0025] S3. Final Refining and Sulfurization

[0026] The rubber compound obtained from S2 was cooled to below 70°C on a two-roll mill. Then, dynamic covalent crosslinking agent, tetrabenzylthiuram disulfide, accelerator Si-69 and sulfur were added in sequence and mixed evenly within 5 minutes.

[0027] S4. Directional Extrusion and Molding

[0028] The material in S3 is extruded using an extruder to obtain the support layer film.

[0029] The second technical problem to be solved by the present invention is to provide a method for preparing a tire tread with low noise and low rolling resistance, which addresses the shortcomings of the existing technology. The tire prepared by this invention significantly reduces tire rolling resistance and driving noise while maintaining good wear resistance and mechanical strength.

[0030] To solve the second technical problem mentioned above, the technical solution of the present invention is:

[0031] A method for preparing a low-noise, low-rolling-resistance tire tread includes the following steps:

[0032] Ⅰ. In an internal mixer, add the continuous phase matrix, then add stearic acid, 2 / 3 of the two-phase structure silica, all the functionalized multi-walled carbon nanotubes and all the bissilane coupling agent, mix at 145-150℃ for 3-5 minutes, discharge the glue and cool to obtain masterbatch A.

[0033] II. Put Masterbatch A back into the internal mixer, add the remaining 1 / 3 of the duplex silica, zinc oxide, and antioxidant, and mix at 120-135℃ for 2-4 minutes. Discharge and cool to obtain Masterbatch B.

[0034] III. In a two-roll mill, add masterbatch B, then add dynamic cross-linked thermoplastic elastomer microparticles and accelerator, and finally add sulfur. Mix for 3-5 minutes, then sheet and cool to obtain a multiphase composite tread rubber.

[0035] IV. The multiphase composite tread compound and the support layer rubber sheet are combined and molded into a complete tire tread blank through thermal bonding or co-extrusion process. Then, the blank is vulcanized in a tire vulcanization mold at 145-160℃ and 15-25MPa pressure for 10-30 minutes to obtain the low-noise, low-rolling-resistance tire tread.

[0036] Due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0037] 1. Solution-polymerized styrene-butadiene rubber in the continuous phase matrix provides excellent wet grip and low heat generation, while neodymium-based cis-butadiene rubber contributes high elasticity and low rolling resistance. Optimization of their ratio achieves complementary performance. In the bissilane coupling agent, sulfur-containing silanes and flexible long-chain silanes work synergistically to ensure strong interfacial bonding between silica and rubber, while also introducing a flexible interfacial layer, significantly reducing the hysteresis loss of the filler network.

[0038] 2. A multi-scale filler / particle system is formed by dual-phase silica (high / low specific surface area blend), functionalized multi-walled carbon nanotubes, and dynamically cross-linked thermoplastic elastomer microparticles. Carbon nanotubes and silica form a mixed conductive / reinforcing network, with the dynamically cross-linked thermoplastic elastomer microparticles acting as uniformly dispersed "elastic buffer spheres." This not only enhances the material's stiffness and strength but, more importantly, the dynamically cross-linked thermoplastic elastomer microparticles and flexible interfaces effectively dissipate and dampen high-frequency vibration energy during driving, which is crucial for reducing tire noise (especially cavity resonance and road noise). The graphene-coated hollow glass microspheres (lightweight and sound-insulating) and the carbon nanotube-grafted silica hybrid filler (high strength and high thermal conductivity) in the support layer further form a synergistic network of "lightweight sound insulation - high-strength support - rapid thermal conduction."

[0039] 3. The multiphase composite tread layer, serving as the ground contact layer, focuses on providing low rolling resistance, excellent wet grip, abrasion resistance, and noise damping, with the core objective of reducing hysteresis heat generation and dissipating vibrations. The support layer, on the other hand, emphasizes high stiffness, high toughness, good deformation resistance, and additional sound insulation and vibration damping functions. Specifically, functionalized solution-polymerized styrene-butadiene rubber and high-vinyl solution-polymerized styrene-butadiene rubber provide a high-strength and low-heat matrix; liquid isoprene rubber, as a plasticizer and reactive component, improves processability and compatibility; chopped aramid fibers provide significant reinforcement and tear resistance; graphene-coated hollow glass microspheres reduce weight while their hollow structure and graphene coating effectively scatter and absorb sound waves; carbon nanotube-grafted silica hybrid filler imparts excellent mechanical properties and thermal conductivity, facilitating rapid heat dissipation; and the introduction of a dynamic covalent crosslinking agent enables the support layer to undergo reversible bond breakage and recombination under large deformations, dissipating energy and improving fatigue resistance and vibration damping. The two layers are tightly bonded together through co-vulcanization. The flexibility and damping properties of the multiphase composite tread layer effectively absorb and isolate high-frequency vibrations generated by road surface excitation, while the high stiffness and dynamic cross-linking network of the support layer suppress low-frequency large deformation and structural vibrations. Together, they achieve effective suppression of noise across the entire frequency band and a significant reduction in rolling resistance, breaking through the performance bottleneck of traditional single-layer treads. Detailed Implementation

[0040] The present invention will be further illustrated below with reference to the embodiments. Example 1

[0041] A method for preparing a low-noise, low-rolling-resistance tire tread includes the following steps:

[0042] A. In an internal mixer, add a continuous phase matrix, then add stearic acid, 2 / 3 of the biphase structure silica, all functionalized multi-walled carbon nanotubes and all of the bissilane coupling agent, mix at 145-150℃ for 3-5 minutes, discharge the glue and cool to obtain masterbatch A.

[0043] B. Put Masterbatch A back into the internal mixer, add the remaining 1 / 3 of the duplex silica, zinc oxide, and antioxidant, and mix at 120-135℃ for 2-4 minutes. Discharge and cool to obtain Masterbatch B.

[0044] C. Add masterbatch B to the open mill, then add dynamic cross-linked thermoplastic elastomer microparticles and accelerator, and finally add sulfur. Mix for 3-5 minutes, then sheet and cool to obtain multiphase composite tread rubber.

[0045] D. Graphene-coated hollow glass microspheres and 1 / 2 of the amount of silane coupling agent are dry-mixed in a high-speed mixer at 80-100℃ and 1500-2000r / min for 10min to obtain pretreated graphene-coated hollow glass microspheres.

[0046] E. The carbon nanotube-grafted silica hybrid filler and the remaining silane coupling agent were ultrasonically treated in an ethanol solution for 30 min, and then the solvent was evaporated to obtain the pretreated carbon nanotube-grafted silica hybrid filler.

[0047] F. First stage mixing: Add epoxy-functionalized solution-polymerized styrene-butadiene rubber, high-vinyl solution-polymerized styrene-butadiene rubber, and liquid isoprene rubber to a mixer and plasticize at 60-70℃ for 1 min. Add pretreated graphene-coated hollow glass microspheres, pretreated carbon nanotube-grafted silica hybrid filler, zinc oxide nanorods, and 4,4'-bis(α,α-dimethylbenzyl)diphenylamine and 2-mercapto-4-methylbenzimidazole zinc salt. Mix at 130-145℃ for 4-5 min to ensure that the filler is fully dispersed and wetted. Discharge the rubber to obtain the first stage masterbatch.

[0048] G. Second stage mixing: Put the first stage masterbatch back into the internal mixer, add chopped aramid fibers, and mix at 100-110℃ and low rotor speed for 2-3 minutes, then discharge the glue;

[0049] H. Heat the rubber compound obtained from G to below 70°C on a two-roll mill, and then add the dynamic covalent crosslinking agent, tetrabenzylthiuram disulfide, accelerator Si-69 and sulfur in sequence, and mix them evenly within 5 minutes.

[0050] I. The material in H is extruded using an extruder to obtain the support layer film;

[0051] J. The multiphase composite tread rubber in C and the support layer rubber in I are combined and molded into a complete tire tread blank through a hot bonding or co-extrusion process. Then, in a tire vulcanization mold, it is vulcanized at 145-160℃ and 15-25MPa pressure for 10-30 minutes to obtain the low-noise, low-rolling-resistance tire tread. Example 2

[0052] Multiphase composite tread rubber and support layer film were prepared according to the method in Example 1, wherein:

[0053] Multiphase composite tread compound formulation (parts by weight, based on the total mass of rubber).

[0054] 100 parts of continuous phase matrix (60 parts of solution-polymerized styrene-butadiene rubber and 40 parts of neodymium-based cis-butadiene rubber), 50 parts of biphase silica (high-structure silica with a specific surface area ≥175 m² / g, accounting for 70% w / w, and low-structure silica with a specific surface area ≤125 m² / g, accounting for 30% w / w), 1 part of carboxyl-functionalized multi-walled carbon nanotubes (MWCNTS-COOH), 5 parts of dynamically cross-linked thermoplastic elastomer microparticles (rubber phase is EPDM rubber, plastic phase is polypropylene, the mass ratio of rubber phase to plastic phase is 60:40, and the particle size is 1 μm), 1.5 parts of zinc oxide, 1 part of stearic acid, 2 parts of antioxidant (1.5 parts of p-phenylenediamine 4010NA and 0.5 parts of quinoline TMQ), and 1 part of accelerator (1 part of sulfenamide DZ and guanidine DPG). 0.5 parts) 1.5 parts, sulfur 0.8 parts; the amount of bis-silane coupling agent (bis-(3-triethoxysilylpropyl)-tetrasulfide accounting for 70% w / w, dodecyltrimethoxysilane accounting for 30% w / w) added is 6% of the total weight of the dual-phase structure silica.

[0055] Support layer formulation (parts by weight)

[0056] Functionalized solution-polymerized styrene-butadiene rubber (SSBR 72612F) 40 parts, high-vinyl solution-polymerized styrene-butadiene rubber (vinyl content not less than 40% w / w, where the vinyl content of the high-vinyl solution-polymerized styrene-butadiene rubber refers to the proportion of vinyl content in the polymer to the total mass of 1,3-butadiene polymerized), liquid isoprene rubber 10 parts, graphene-coated hollow glass microspheres (prepared by the method of preparing graphene oxide-coated hollow glass microspheres in CN107540239A), chopped aramid fibers 5 parts, carbon nanotube-grafted silica hybrid filler (multi-walled carbon nanotubes are acidified, and silica is treated with aminosilane). The process involves chemical treatment followed by amidation of carboxylated carbon nanotubes and aminoized silica in the presence of the condensing agent dicyclohexylcarbodiimide. The resulting product is obtained after washing and drying. The composition includes: 10 parts carbon nanotubes (1:5 weight ratio of carbon nanotubes to silica); 1 part dynamic covalent crosslinking agent (generated by the reaction of furan methacrylate and maleimide propyltriethoxysilane); 3 parts zinc oxide nanorods; 1 part 4,4'-bis(α,α-dimethylbenzyl)diphenylamine; 0.5 parts 2-mercapto-4-methylbenzimidazole zinc salt; 0.3 parts tetrabenzylthiuram disulfide; 1 part accelerator Si-69; and 0.8 parts sulfur. The amount of silane coupling agent (aminosilane) added is 5% of the total weight of the graphene-coated hollow glass microspheres and carbon nanotube-grafted silica hybrid filler.

[0057] Multiphase composite tread rubber and support layer rubber are combined and molded into a complete tire tread blank through a thermal bonding process. Then, it is vulcanized in a tire vulcanization mold at 145°C and 15MPa pressure for 30 minutes to obtain the low-noise, low-rolling-resistance tire tread. Example 3

[0058] Multiphase composite tread rubber and support layer film were prepared according to the method in Example 1, wherein:

[0059] Multiphase composite tread compound formulation (parts by weight)

[0060] 100 parts of continuous phase matrix (70 parts of solution-polymerized styrene-butadiene rubber and 30 parts of neodymium-based cis-butadiene rubber), 60 parts of biphase silica (high-structure silica with a specific surface area ≥175 m² / g, accounting for 70% w / w, and low-structure silica with a specific surface area ≤125 m² / g, accounting for 30% w / w), 2 parts of carboxyl-functionalized multi-walled carbon nanotubes (MWCNTS-COOH), 10 parts of dynamically cross-linked thermoplastic elastomer microparticles (rubber phase is EPDM rubber, plastic phase is polypropylene, the mass ratio of rubber phase to plastic phase is 60:40, and the particle size is 3 μm), 2.2 parts of zinc oxide, 1.5 parts of stearic acid, 3.5 parts of antioxidant (2.2 parts of p-phenylenediamine 4010NA and 1.3 parts of quinoline TMQ), and 1.5 parts of accelerator (1.5 parts of sulfenamide DZ and 1.5 parts of thiuram TBTD). 1 part) 2.5 parts, sulfur 1.3 parts; the amount of bis-silane coupling agent (bis-(3-triethoxysilylpropyl)-tetrasulfide accounting for 78% w / w, dodecyltrimethoxysilane accounting for 22% w / w) added is 8% of the total weight of the dual-phase structure silica.

[0061] Support layer formulation (parts by weight)

[0062] Functionalized solution-polymerized styrene-butadiene rubber (SSBR 72612F) 45 parts, high-vinyl solution-polymerized styrene-butadiene rubber (vinyl content not less than 40% w / w, where the vinyl content of the high-vinyl solution-polymerized styrene-butadiene rubber refers to the proportion of vinyl content in the polymer to the total mass of 1,3-butadiene polymerized), liquid isoprene rubber 12 parts, graphene-coated hollow glass microspheres (prepared by the method of preparing graphene oxide-coated hollow glass microspheres in CN107540239A), chopped aramid fibers 8 parts, carbon nanotube-grafted silica hybrid filler (multi-walled carbon nanotubes are acidified, and silica is simultaneously aminosilanized). The process involves treating the carbon nanotubes and then, in the presence of the condensing agent dicyclohexylcarbodiimide, subjecting the carboxylated carbon nanotubes to an amidation reaction with the aminated silica. The resulting product is obtained after washing and drying. The composition includes: 12 parts carbon nanotubes (1:5 weight ratio) of silica; 2 parts dynamic covalent crosslinking agent (generated by the reaction of furan methacrylate and maleimide propyltriethoxysilane); 4 parts zinc oxide nanorods; 1.2 parts 4,4'-bis(α,α-dimethylbenzyl)diphenylamine; 0.8 parts 2-mercapto-4-methylbenzimidazole zinc salt; 0.45 parts tetrabenzylthiuram disulfide; 1.5 parts accelerator Si-69; and 1 part sulfur. The amount of silane coupling agent (vinylsilane) added is 6.5% of the total weight of the graphene-coated hollow glass microspheres and carbon nanotube-grafted silica hybrid filler.

[0063] Multiphase composite tread rubber and support layer rubber are compounded and formed into a complete tire tread blank through thermal bonding or co-extrusion process. Then, it is vulcanized in a tire vulcanization mold at 150°C and 20MPa pressure for 20 minutes to obtain the low-noise, low-rolling-resistance tire tread. Example 4

[0064] Multiphase composite tread rubber and support layer film were prepared according to the method in Example 1, wherein:

[0065] Multiphase composite tread compound formulation (parts by weight)

[0066] 100 parts of continuous phase matrix (80 parts of solution-polymerized styrene-butadiene rubber and 20 parts of neodymium-based cis-butadiene rubber), 70 parts of biphase silica (high-structure silica with a specific surface area ≥175 m² / g, accounting for 70% w / w, and low-structure silica with a specific surface area ≤125 m² / g, accounting for 30% w / w), 3 parts of carboxyl-functionalized multi-walled carbon nanotubes (MWCNTS-COOH), and dynamically crosslinked thermoplastic elastomer microparticles (rubber phase is EPDM rubber, plastic phase is polypropylene, and rubber phase and... The mass ratio of the plastic phase is 60:40, with a particle size of 5 μm. The composition includes 15 parts of plastic phase, 3.0 parts of zinc oxide, 2 parts of stearic acid, 5 parts of antioxidant (3 parts of p-phenylenediamine and 2 parts of quinoline), 3.5 parts of accelerator (2 parts of sulfenamide and 1.5 parts of thiuram), and 1.8 parts of sulfur. The amount of bis-silane coupling agent (85% w / w of bis-(3-triethoxysilylpropyl)-tetrasulfide and 15% w / w of dodecyltrimethoxysilane) added is 10% of the total weight of the dual-phase silica.

[0067] Support layer formulation (parts by weight)

[0068] Functionalized solution-polymerized styrene-butadiene rubber (SSBR 72612F) 50 parts, high-vinyl solution-polymerized styrene-butadiene rubber (vinyl content not less than 40% w / w, where the vinyl content of the high-vinyl solution-polymerized styrene-butadiene rubber refers to the proportion of vinyl content in the polymer to the total mass of 1,3-butadiene polymerized), liquid isoprene rubber 15 parts, graphene-coated hollow glass microspheres (prepared by the method of preparing graphene oxide-coated hollow glass microspheres in CN107540239A), chopped aramid fibers 10 parts, carbon nanotube-grafted silica hybrid filler (multi-walled carbon nanotubes are acidified, and silica is treated with aminosilicone). The mixture undergoes alkylation treatment, followed by amidation reaction of carboxylated carbon nanotubes and aminated silica in the presence of the condensing agent dicyclohexylcarbodiimide. After washing and drying, the resulting product is as follows: 15 parts of carbon nanotubes to silica (weight ratio 1:5), 3 parts of dynamic covalent crosslinking agent (generated by the reaction of furan methacrylate and maleimide propyltriethoxysilane), 5 parts of zinc oxide nanorods, 1.5 parts of 4,4'-bis(α,α-dimethylbenzyl)diphenylamine, 1 part of 2-mercapto-4-methylbenzimidazole zinc salt, 0.6 parts of tetrabenzylthiuram disulfide, 2 parts of accelerator Si-69, and 1.2 parts of sulfur. The amount of silane coupling agent (vinylsilane) added is 8% of the total weight of the graphene-coated hollow glass microspheres and carbon nanotube-grafted silica hybrid filler.

[0069] Multiphase composite tread rubber and support layer rubber are compounded and formed into a complete tire tread blank through thermal bonding or co-extrusion process. Then, it is vulcanized in a tire vulcanization mold at 160°C and 25MPa pressure for 10 minutes to obtain the low-noise, low-rolling-resistance tire tread. Comparative Example 1

[0070] The multiphase composite tread compound omits the functionalized multi-walled carbon nanotubes, but otherwise remains identical to Example 3. Comparative Example 2

[0071] In the multiphase composite tread compound, the biphase structure silica was replaced with an equal amount of high-structure silica, and the rest was exactly the same as in Example 3. Comparative Example 3

[0072] The dynamic cross-linked thermoplastic elastomer microparticles are omitted from the multiphase composite tread compound, but the rest is exactly the same as in Example 3. Comparative Example 4

[0073] The graphene-coated hollow glass microspheres in the support layer are omitted, but otherwise they are exactly the same as in Example 3. Comparative Example 5

[0074] The support layer is removed, and only the multiphase composite tread rubber (single-layer structure) is retained. Comparative Example 6

[0075] In the multiphase composite tread compound, the bissilane coupling agent was replaced with an equal amount of a single sulfur-containing silane, and the rest was exactly the same as in Example 3.

[0076] The following results were obtained through the examples and comparative examples:

[0077] Table 1

[0078]

[0079] Based on the above data, we can conclude that:

[0080] Functionalized multi-walled carbon nanotubes (Comparative Example 1) can be used to construct a reinforcing network. When these networks are missing, rolling resistance increases and strength and fatigue resistance decrease significantly.

[0081] The compound system of dual-phase silica (Comparative Example 2) can reduce hysteresis loss, while single high-structure silica will lead to a significant increase in rolling resistance and noise.

[0082] Dynamically cross-linked thermoplastic elastomer microparticles (Comparative Example 3) are the core of noise reduction; their absence increases the noise level by more than 12 dB.

[0083] Graphene-coated hollow glass microspheres (Comparative Example 4) can enhance sound insulation; after removal, both noise and rolling resistance increase.

[0084] The double-layer structure (comparative example 5) is the key to breaking through the "devil's triangle", while the performance of a single-layer tread is completely degraded;

[0085] The synergistic effect of bissilane coupling agents (Comparative Example 6) can optimize interfacial bonding, while a single sulfur-containing silane will increase hysteresis heat generation, leading to increased rolling resistance.

[0086] This invention achieves the core objectives of low rolling resistance and low noise, while maintaining excellent wear resistance and mechanical strength.

[0087] It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

Claims

1. A low-noise, low-rolling-resistance tire tread, characterized in that: Includes the support layer and multiphase composite tread compound; The multiphase composite tread compound includes a continuous phase matrix, a two-phase structured silica, functionalized multi-walled carbon nanotubes, a bissilane coupling agent, dynamically cross-linked thermoplastic elastomer microparticles, zinc oxide, stearic acid, antioxidants, accelerators, and sulfur. The weight ratio of the continuous phase matrix, biphase silica, functionalized multi-walled carbon nanotubes, dynamically cross-linked thermoplastic elastomer microparticles, zinc oxide, stearic acid, antioxidant, accelerator, and sulfur in the multiphase composite tread compound is 100:50-70:1-3:5-15:1.5-3.0:1-2:2-5:1.5-3.5:0.8-1.

8. The amount of bissilane coupling agent added is 6-10% w / w of the total weight of the dual-phase silica; The continuous phase matrix comprises solution-polymerized styrene-butadiene rubber and neodymium-based cis-butadiene rubber, wherein the weight ratio of solution-polymerized styrene-butadiene rubber to neodymium-based cis-butadiene rubber is 60-80:20-40; The specific surface area of ​​the high-structure silica in the dual-phase silica is ≥175m² / g, and the specific surface area of ​​the low-structure silica is ≤125m² / g. The mass ratio of high-structure silica to low-structure silica is 7:

3. In the bissilane coupling agent, sulfur-containing silanes account for 70-85% w / w of the total silane content, and flexible long-chain silanes account for 15-30% w / w of the total silane content; The supporting layer is composed of functionalized solution-polymerized styrene-butadiene rubber, high-vinyl solution-polymerized styrene-butadiene rubber, liquid isoprene rubber, graphene-coated hollow glass microspheres, chopped aramid fibers, carbon nanotube-grafted silica hybrid filler, dynamic covalent crosslinking agent, zinc oxide nanorods, 4,4'-bis(α,α-dimethylbenzyl)diphenylamine, 2-mercapto-4-methylbenzimidazole zinc salt, tetrabenzylthiuram disulfide, accelerator Si-69, and sulfur in a weight ratio of 40-50:30-40:10-15:15-25:5-10:10-15:1-3:3-5:1-1.5:0.5-1:0.3-0.6:1-2:0.8-1.

2. The support layer also includes a silane coupling agent, which is added at 5-8% w / w of the total weight of the graphene-coated hollow glass microspheres and carbon nanotube-grafted silica hybrid filler.

2. The low-noise, low-rolling-resistance tire tread as described in claim 1, characterized in that: The dynamically cross-linked thermoplastic elastomer microparticles are EPDM / PP based and have a particle size of 1-5 μm; The antioxidants include p-phenylenediamine antioxidants and quinoline antioxidants, with a weight ratio of p-phenylenediamine antioxidants to quinoline antioxidants of 1.5-3:0.5-2.

3. The low-noise, low-rolling-resistance tire tread as described in claim 1, characterized in that: The accelerator includes a sulfenamide primary accelerator and a guanidine or thiuram secondary accelerator, with the weight ratio of the primary accelerator to the secondary accelerator being 1-2:0.5-1.

5.

4. The low-noise, low-rolling-resistance tire tread as described in claim 1, characterized in that, The method for preparing the support layer includes the following steps: S1. Filler predispersion and functionalization S1-1. Graphene-coated hollow glass microspheres and 1 / 2 of the amount of silane coupling agent are dry-mixed in a high-speed mixer at 80-100℃ and 1500-2000r / min for 10min to obtain pretreated graphene-coated hollow glass microspheres. S1-2. The carbon nanotube-grafted silica hybrid filler and the remaining silane coupling agent were ultrasonically treated in an ethanol solution for 30 min, and then the solvent was evaporated to obtain the pretreated carbon nanotube-grafted silica hybrid filler. S2. Segmented mixing of masterbatch S2-1. First stage mixing: Functionalized solution-polymerized styrene-butadiene rubber, high-vinyl solution-polymerized styrene-butadiene rubber, and liquid isoprene rubber are added to an internal mixer and plasticized at 60-70℃ for 1 min. Pretreated graphene-coated hollow glass microspheres, pretreated carbon nanotube-grafted silica hybrid filler, zinc oxide nanorods, and 4,4'-bis(α,α-dimethylbenzyl)diphenylamine and 2-mercapto-4-methylbenzimidazole zinc salt are added and mixed at 130-145℃ for 4-5 min to ensure that the filler is fully dispersed and wetted. The first stage masterbatch is obtained by debinding. S2-2. Two-stage mixing: Put the first-stage masterbatch back into the internal mixer, add chopped aramid fibers, and mix at 100-110℃ and a low rotor speed for 2-3 minutes, then discharge the glue. S3. Final Refining and Sulfurization The rubber compound obtained from S2 was cooled to below 70°C on a two-roll mill. Then, dynamic covalent crosslinking agent, tetrabenzylthiuram disulfide, accelerator Si-69 and sulfur were added in sequence and mixed evenly within 5 minutes. S4. Directional Extrusion and Molding The material in S3 is extruded using an extruder to obtain the support layer film.

5. The method for preparing a low-noise, low-rolling-resistance tire tread as described in any one of claims 1-4, characterized in that, Includes the following steps: Ⅰ. In an internal mixer, add the continuous phase matrix, then add stearic acid, 2 / 3 of the two-phase structure silica, all the functionalized multi-walled carbon nanotubes and all the bissilane coupling agent, mix at 145-150℃ for 3-5 minutes, discharge the glue and cool to obtain masterbatch A. II. Put Masterbatch A back into the internal mixer, add the remaining 1 / 3 of the duplex silica, zinc oxide, and antioxidant, and mix at 120-135℃ for 2-4 minutes. Discharge and cool to obtain Masterbatch B. III. In a two-roll mill, add masterbatch B, then add dynamic cross-linked thermoplastic elastomer microparticles and accelerator, and finally add sulfur. Mix for 3-5 minutes, then sheet and cool to obtain a multiphase composite tread rubber. IV. The multiphase composite tread compound and the support layer rubber sheet are combined and molded into a complete tire tread blank through thermal bonding or co-extrusion process. Then, the blank is vulcanized in a tire vulcanization mold at 145-160℃ and 15-25MPa pressure for 10-30 minutes to obtain the low-noise, low-rolling-resistance tire tread.

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