Low-resistance high-wear-resistance tire rubber composition as well as preparation method and application thereof

Abstract

The invention discloses a low-resistance and high-wear-resistance tire rubber composition as well as a preparation method and application thereof, and belongs to the technical field of rubber materials. The tire rubber composition comprises the following raw materials in parts by weight: 50-70 parts of natural rubber NR, 30-50 parts of solution polymerized styrene-butadiene rubber SSBR, 40-60 parts of modified white carbon black, 3-5 parts of zinc oxide, 1-2 parts of stearic acid, 1-3 parts of an anti-aging agent 6PPD and 2.5-3.5 parts of a vulcanization system. The prepared tire rubber material has the advantages that the rolling resistance is obviously reduced, the wear resistance is improved, the energy consumption is effectively reduced, and the requirements of new energy automobiles on high-performance tires are met. Through three-step modification treatment, the white carbon black is uniformly dispersed in a rubber matrix, and the interface bonding is firm, so that the prepared tire can reduce the rolling resistance of the tire using the tread rubber, and the tread rubber has higher wear resistance, tensile strength and elongation at break, and accords with the development direction of new energy automobiles in the future.

Description

Technical Field

[0001] The invention belongs to the technical field of rubber materials, and in particular relates to a low-resistance and high-wear-resistant tire rubber composition, a preparation method and an application thereof. Background Art

[0002] With the rapid development of China's highways and heavy industry, the requirements for tire quality are increasing. New energy vehicles have higher requirements for tire performance, including low rolling resistance (to improve endurance), high wet skid resistance (to ensure safety) and wear resistance (to extend life). New energy vehicle tires must meet the requirements of high inflation pressure, low noise and lightweight, while the sidewall strength of traditional tires in existing technologies is insufficient, the rolling resistance ratio is high, and the increase in vehicle body mass will accelerate tire wear.

[0003] The base material of tire rubber is rubber, but rubber material has large free volume, small intermolecular force, low glass transition temperature and amorphous high elastic state, so most rubber cannot be used without filler reinforcement. As a reinforcing filler, white carbon black can improve the anti-skid performance of tires and effectively reduce their rolling resistance, but white carbon black is very easy to agglomerate, and the interface between white carbon black and rubber matrix is ​​weak, so the reinforcement effect is not very ideal.

[0004] In the prior art, in order to improve the dispersibility of silica and enhance the compatibility of silica with the base material, the added silica is often modified by a silane coupling agent or a surfactant, or a silane coupling agent and a silica dispersant are added at the same time as the silica in the rubber refining process.

[0005] CN113929978B discloses a solid aircraft tire tread rubber and a preparation method thereof, wherein the raw material components include: natural rubber, white carbon black, silane coupling agent, white carbon black dispersant, N660 carbon black, etc. In the invention, white carbon black, silane coupling agent, and white carbon black dispersant are directly added in the mixing step. The silane coupling agent and the white carbon black dispersant can improve the dispersibility of white carbon black in the rubber matrix, but the directly added silane coupling agent has an unsatisfactory dispersing effect, resulting in poor dispersion stability of white carbon black and easy re-agglomeration, which cannot effectively improve the anti-skid performance of the tire using the tread rubber, nor can it effectively reduce its rolling resistance.

[0006] CN113502135B discloses a self-repairing rubber composition for tires and its preparation method, which uses a variety of materials such as reverse vulcanized rubber prepolymer, liquid isoprene, modified white carbon black, tackifying resin, etc. The modified white carbon black in the invention is hydrated silicon dioxide with the following groups modified on the surface: vinyl-triethoxysilane, dimethyldichlorosilane, polyethylene glycol-6000. The invention uses silane coupling agent or surfactant to modify white carbon black. Although this method improves the compatibility of white carbon black with the rubber matrix, it will cause the vulcanization of the rubber material to be delayed, resulting in a decrease in the tensile strength, elongation at break and wear resistance of the tread rubber.

[0007] Therefore, how to achieve effective dispersion of fillers in the rubber matrix is ​​a technical problem that needs to be solved urgently. Summary of the invention

[0008] In view of the problems existing in the prior art, the present invention provides a new tire rubber formula and a preparation method thereof, which significantly improves the uniform distribution of fillers in the rubber matrix and effectively reduces rolling resistance while maintaining excellent wear resistance and mechanical properties, thereby solving the problems of uneven dispersion and performance degradation in the prior art.

[0009] In order to achieve the above technical objectives, the technical solution adopted by the present invention is: A low-resistance and high-wear-resistant tire rubber composition comprises the following raw materials in parts by weight: 50-70 parts of natural rubber NR, 30-50 parts of solution-polymerized styrene-butadiene rubber SSBR, 40-60 parts of modified white carbon black, 3-5 parts of zinc oxide, 1-2 parts of stearic acid, 1-3 parts of antioxidant 6PPD, and 2.5-3.5 parts of a vulcanization system.

[0010] Furthermore, the vulcanization system includes 2.0-2.8 parts of sulfur and 0.5-0.7 parts of an accelerator; the accelerator is one or more of tetramethylthiuram disulfide TMTD or N-cyclohexyl-2-benzothiazole sulfenamide CBS.

[0011] Furthermore, the preparation method of the modified silica is: (1) adding white carbon black to anhydrous ethanol at a solid-liquid ratio of 1:5, ultrasonically treating for 60 minutes, transferring to a vacuum drying oven, and dehydrating at 60° C. to a moisture content of less than 0.3%, thereby obtaining pretreated white carbon black; (2) mixing an aluminate coupling agent with anhydrous ethanol at a mass ratio of 1:4, stirring at 50° C. for 30 minutes to obtain an aluminate coupling agent hydrolyzate; mixing a silane coupling agent Si75 with an ethanol solution having a mass concentration of 90% at a mass ratio of 1:9, adjusting the pH to 4.5, and hydrolyzing at 40° C. for 1 hour to obtain a silane coupling agent Si75 hydrolyzate; (3) First-stage modification: put the pretreated silica into a stirred reactor, heat it to 80 °C, add 1-butyl-3-methylimidazolium tetrafluoroborate at 10% of the mass of silica, and stir at 2000 rpm for 30 minutes; (4) Second stage modification: Maintain the temperature at 80°C, slowly add aluminate coupling agent hydrolyzate, the amount of aluminate coupling agent hydrolyzate is 10% of the mass of white carbon black, and continue stirring to react for 1 hour; (5) Three-stage modification: the temperature was raised to 100 °C, and the hydrolyzate of silane coupling agent Si75 was added. The amount of silane coupling agent Si75 hydrolyzate was 10% of the mass of white carbon black. The mixture was stirred at 1500 rpm for 45 minutes to complete the condensation reaction. (6) Post-treatment and drying: The three-stage modified slurry is treated by a spray dryer and ground to obtain modified silica.

[0012] Furthermore, in step (1), the ultrasonic treatment power was 800 W and the frequency was 40 kHz.

[0013] Furthermore, nitrogen protection is introduced during steps (3-5) to avoid moisture interference.

[0014] Furthermore, the spray drying temperature in step (6) does not exceed 150°C.

[0015] Furthermore, the model of the aluminate coupling agent is DL-411, which was purchased from Dinghai Plastic Chemical Co., Ltd.

[0016] A method for preparing a low-resistance and high-wear-resistant tire rubber composition comprises the following preparation steps: A. Preparation of modified silica; B. Pre-mixing stage: put natural rubber NR and solution polystyrene butadiene rubber SSBR into the internal mixer according to the proportion, control the initial temperature at 80-90℃, and plasticize for 4-6 minutes until the roller is wrapped; add modified white carbon black, zinc oxide, stearic acid and antioxidant 6PPD in sequence, open the cooling water system of the internal mixer, control the mixing temperature at 110-120℃, mix for 8-10 minutes to form a homogeneous rubber compound; discharge the material when the torque curve fluctuation amplitude is ≤5%, and let it stand for 24 hours to release the internal stress; C. Final mixing stage: put the static rubber back into the internal mixer, reduce the temperature to 60-70℃, add sulfur and accelerator, mix for 3-4 minutes to ensure that the vulcanizer is evenly dispersed; D. Vulcanization molding: Put the mixed rubber into the mold, heat it to 150-160℃, maintain the pressure for 1 hour to complete the vulcanization reaction, take it out and cool it to room temperature to obtain the finished tire rubber.

[0017] A low-resistance and high-wear-resistant tire rubber composition is suitable for new energy vehicle tires. The composition significantly improves the rolling resistance and wear resistance of the tire by optimizing filler dispersion and interface bonding, prolongs the service life, reduces energy consumption, and meets the requirements of new energy vehicles for high-performance tires.

[0018] At present, the existing technology has poor dispersion of silica in the rubber matrix and weak interface bonding, which makes it difficult to balance rolling resistance and wear resistance. Therefore, how to change the traditional modification method to achieve efficient dispersion and strong interface bonding of silica has become the key to improving tire performance.

[0019] Therefore, in the present invention, through three-step staged treatment (ionic liquid physical coating→aluminate coupling agent chemical bonding→silane reinforcement cross-linking), gradient functionalization can be achieved to meet the performance requirements of tire rubber for white carbon black.

[0020] First, the present invention disperses white carbon black in anhydrous ethanol to break the hard agglomerates of white carbon black and expose the surface hydroxyl groups. The aluminate coupling agent is pre-hydrolyzed and partially hydrolyzed to generate active Al-OH groups to enhance the reactivity with white carbon black. The silane coupling agent Si75 generates silanol (-Si-OH) to prepare for the condensation reaction.

[0021] Secondly, the silica was modified in three stages. In the first stage, ionic liquid (1-butyl-3-methylimidazolium tetrafluoroborate) was added for intercalation modification. The imidazolium cation was embedded in the silica interlayer, and the anion BF 4 - Adsorbed on the surface to inhibit agglomeration. In the second stage, aluminate coupling agent is added, and Al-OH bonds with the surface hydroxyl group of silica to form a strong interface bond. In the third stage, silane coupling agent Si75 is introduced, and silanol condenses with silica to form a three-dimensional cross-linked network, which significantly improves the filler dispersion and interfacial bonding strength. Ionic liquid physical coating → aluminate coupling agent chemical bonding → silane reinforcement cross-linking, the synergistic effect of the three makes silica uniformly dispersed in the rubber matrix, the interface bonding is firm, effectively reducing rolling resistance, improving wear resistance, extending tire service life, meeting the stringent requirements of new energy vehicles for high-performance tires, and promoting green travel.

[0022] Beneficial effects: The tire rubber prepared by the present invention not only significantly reduces rolling resistance, improves wear resistance, and effectively reduces energy consumption, but also meets the demand of new energy vehicles for high-performance tires. Through the three-step modification treatment, white carbon black is evenly dispersed in the rubber matrix, and the interface bonding is firm. The prepared tire can reduce the rolling resistance of the tire using the tread rubber, and make the tread rubber have higher wear resistance, tensile strength and elongation at break, which meets the development direction of future new energy vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is an AFM photo of the rubber compound of Example 1 of the present invention; Figure 2 AFM photograph comparison of the rubber materials of Comparative Examples 1-5 and Example 1. DETAILED DESCRIPTION

[0024] The technical solution of the present invention is further described below in conjunction with specific embodiments, but is not limited thereto.

[0025] Example 1 A low-resistance and high-wear-resistant tire rubber composition comprises the following raw materials in parts by weight: 50 parts of natural rubber NR, 50 parts of solution-polymerized styrene-butadiene rubber SSBR, 40 parts of modified white carbon black, 3 parts of zinc oxide, 1 part of stearic acid, 1 part of antioxidant 6PPD, and 2.5 parts of a vulcanization system.

[0026] The vulcanization system includes 2.0 parts of sulfur and 0.5 parts of an accelerator; the accelerator is tetramethylthiuram disulfide TMTD.

[0027] The preparation method of the modified white carbon black is: (1) adding white carbon black to anhydrous ethanol at a solid-liquid ratio of 1:5, ultrasonically treating for 60 minutes, transferring to a vacuum drying oven, and dehydrating at 60° C. to a moisture content of less than 0.3%, thereby obtaining pretreated white carbon black; (2) mixing an aluminate coupling agent with anhydrous ethanol at a mass ratio of 1:4, stirring at 50° C. for 30 minutes to obtain an aluminate coupling agent hydrolyzate; mixing a silane coupling agent Si75 with an ethanol solution having a mass concentration of 90% at a mass ratio of 1:9, adjusting the pH to 4.5, and hydrolyzing at 40° C. for 1 hour to obtain a silane coupling agent Si75 hydrolyzate; (3) First-stage modification: put the pretreated silica into a stirred reactor, heat it to 80 °C, add 1-butyl-3-methylimidazolium tetrafluoroborate at 10% of the mass of silica, and stir at 2000 rpm for 30 minutes; (4) Second stage modification: Maintain the temperature at 80°C, slowly add aluminate coupling agent hydrolyzate, the amount of aluminate coupling agent hydrolyzate is 10% of the mass of white carbon black, and continue stirring to react for 1 hour; (5) Three-stage modification: the temperature was raised to 100 °C, and the hydrolyzate of silane coupling agent Si75 was added. The amount of silane coupling agent Si75 hydrolyzate was 10% of the mass of white carbon black. The mixture was stirred at 1500 rpm for 45 minutes to complete the condensation reaction. (6) Post-treatment and drying: The three-stage modified slurry is treated by a spray dryer and ground to obtain modified silica.

[0028] Step (1) Ultrasonic treatment power 800 W, frequency 40 kHz.

[0029] During steps (3-5), nitrogen gas was introduced to protect the system and avoid moisture interference.

[0030] The spray drying temperature in step (6) does not exceed 150°C.

[0031] A method for preparing a low-resistance and high-wear-resistant tire rubber composition comprises the following preparation steps: A. Preparation of modified silica; B. Pre-mixing stage: put natural rubber NR and solution polystyrene butadiene rubber SSBR into the internal mixer according to the proportion, control the initial temperature at 80-90℃, and plasticize for 4-6 minutes until the roller is wrapped; add modified white carbon black, zinc oxide, stearic acid and antioxidant 6PPD in sequence, open the cooling water system of the internal mixer, control the mixing temperature at 110-120℃, mix for 8-10 minutes to form a homogeneous rubber compound; discharge the material when the torque curve fluctuation amplitude is ≤5%, and let it stand for 24 hours to release the internal stress; C. Final mixing stage: put the static rubber back into the internal mixer, reduce the temperature to 60-70℃, add sulfur and accelerator, mix for 3-4 minutes to ensure that the vulcanizer is evenly dispersed; D. Vulcanization molding: Put the mixed rubber into the mold, heat it to 150-160℃, maintain the pressure for 1 hour to complete the vulcanization reaction, take it out and cool it to room temperature to obtain the finished tire rubber.

[0032] Example 2 A low-resistance and high-wear-resistant tire rubber composition comprises the following raw materials in parts by weight: 60 parts of natural rubber NR, 35 parts of solution-polymerized styrene-butadiene rubber SSBR, 50 parts of modified white carbon black, 3 parts of zinc oxide, 1 part of stearic acid, 2 parts of antioxidant 6PPD, and 2.5 parts of a vulcanization system.

[0033] The vulcanization system includes 2.0 parts of sulfur and 0.5 parts of an accelerator; the accelerator is N-cyclohexyl-2-benzothiazole sulfenamide CBS.

[0034] The preparation method of the modified white carbon black is: (1) adding white carbon black to anhydrous ethanol at a solid-liquid ratio of 1:5, ultrasonically treating for 60 minutes, transferring to a vacuum drying oven, and dehydrating at 60° C. to a moisture content of less than 0.3%, thereby obtaining pretreated white carbon black; (2) mixing an aluminate coupling agent with anhydrous ethanol at a mass ratio of 1:4, stirring at 50° C. for 30 minutes to obtain an aluminate coupling agent hydrolyzate; mixing a silane coupling agent Si75 with an ethanol solution having a mass concentration of 90% at a mass ratio of 1:9, adjusting the pH to 4.5, and hydrolyzing at 40° C. for 1 hour to obtain a silane coupling agent Si75 hydrolyzate; (3) First-stage modification: put the pretreated silica into a stirred reactor, heat it to 80 °C, add 1-butyl-3-methylimidazolium tetrafluoroborate at 10% of the mass of silica, and stir at 2000 rpm for 30 minutes; (4) Second stage modification: Maintain the temperature at 80°C, slowly add aluminate coupling agent hydrolyzate, the amount of aluminate coupling agent hydrolyzate is 10% of the mass of white carbon black, and continue stirring to react for 1 hour; (5) Three-stage modification: the temperature was raised to 100 °C, and the hydrolyzate of silane coupling agent Si75 was added. The amount of silane coupling agent Si75 hydrolyzate was 10% of the mass of white carbon black. The mixture was stirred at 1500 rpm for 45 minutes to complete the condensation reaction. (6) Post-treatment and drying: The three-stage modified slurry is treated by a spray dryer and ground to obtain modified silica.

[0035] Step (1) Ultrasonic treatment power 800 W, frequency 40 kHz.

[0036] During steps (3-5), nitrogen gas was introduced to protect the system and avoid moisture interference.

[0037] The spray drying temperature in step (6) does not exceed 150°C.

[0038] A method for preparing a low-resistance and high-wear-resistant tire rubber composition comprises the following preparation steps: A. Preparation of modified silica; B. Pre-mixing stage: put natural rubber NR and solution polystyrene butadiene rubber SSBR into the internal mixer according to the proportion, control the initial temperature at 80-90℃, and plasticize for 4-6 minutes until the roller is wrapped; add modified white carbon black, zinc oxide, stearic acid and antioxidant 6PPD in sequence, open the cooling water system of the internal mixer, control the mixing temperature at 110-120℃, mix for 8-10 minutes to form a homogeneous rubber compound; discharge the material when the torque curve fluctuation amplitude is ≤5%, and let it stand for 24 hours to release the internal stress; C. Final mixing stage: put the static rubber back into the internal mixer, reduce the temperature to 60-70℃, add sulfur and accelerator, mix for 3-4 minutes to ensure that the vulcanizer is evenly dispersed; D. Vulcanization molding: Put the mixed rubber into the mold, heat it to 150-160℃, maintain the pressure for 1 hour to complete the vulcanization reaction, take it out and cool it to room temperature to obtain the finished tire rubber.

[0039] Example 3 A low-resistance and high-wear-resistant tire rubber composition comprises the following raw materials in parts by weight: 65 parts of natural rubber NR, 45 parts of solution-polymerized styrene-butadiene rubber SSBR, 45 parts of modified white carbon black, 5 parts of zinc oxide, 2 parts of stearic acid, 1 part of antioxidant 6PPD, and 3 parts of vulcanization system.

[0040] The vulcanization system includes 2.5 parts of sulfur and 0.5 parts of an accelerator; the accelerator is tetramethylthiuram disulfide TMTD or N-cyclohexyl-2-benzothiazole sulfenamide CBS mixed in a mass ratio of 1:1.

[0041] The preparation method of the modified white carbon black is: (1) adding white carbon black to anhydrous ethanol at a solid-liquid ratio of 1:5, ultrasonically treating for 60 minutes, transferring to a vacuum drying oven, and dehydrating at 60° C. to a moisture content of less than 0.3%, thereby obtaining pretreated white carbon black; (2) mixing an aluminate coupling agent with anhydrous ethanol at a mass ratio of 1:4, stirring at 50° C. for 30 minutes to obtain an aluminate coupling agent hydrolyzate; mixing a silane coupling agent Si75 with an ethanol solution having a mass concentration of 90% at a mass ratio of 1:9, adjusting the pH to 4.5, and hydrolyzing at 40° C. for 1 hour to obtain a silane coupling agent Si75 hydrolyzate; (3) First-stage modification: put the pretreated silica into a stirred reactor, heat it to 80 °C, add 1-butyl-3-methylimidazolium tetrafluoroborate at 10% of the mass of silica, and stir at 2000 rpm for 30 minutes; (4) Second stage modification: Maintain the temperature at 80°C, slowly add aluminate coupling agent hydrolyzate, the amount of aluminate coupling agent hydrolyzate is 10% of the mass of white carbon black, and continue stirring to react for 1 hour; (5) Three-stage modification: the temperature was raised to 100 °C, and the hydrolyzate of silane coupling agent Si75 was added. The amount of silane coupling agent Si75 hydrolyzate was 10% of the mass of white carbon black. The mixture was stirred at 1500 rpm for 45 minutes to complete the condensation reaction. (6) Post-treatment and drying: The three-stage modified slurry is treated by a spray dryer and ground to obtain modified silica.

[0042] Step (1) Ultrasonic treatment power 800 W, frequency 40 kHz.

[0043] During steps (3-5), nitrogen gas was introduced to protect the system and avoid moisture interference.

[0044] The spray drying temperature in step (6) does not exceed 150°C.

[0045] A method for preparing a low-resistance and high-wear-resistant tire rubber composition comprises the following preparation steps: A. Preparation of modified silica; B. Pre-mixing stage: put natural rubber NR and solution polystyrene butadiene rubber SSBR into the internal mixer according to the proportion, control the initial temperature at 80-90℃, and plasticize for 4-6 minutes until the roller is wrapped; add modified white carbon black, zinc oxide, stearic acid and antioxidant 6PPD in sequence, open the cooling water system of the internal mixer, control the mixing temperature at 110-120℃, mix for 8-10 minutes to form a homogeneous rubber compound; discharge the material when the torque curve fluctuation amplitude is ≤5%, and let it stand for 24 hours to release the internal stress; C. Final mixing stage: put the static rubber back into the internal mixer, reduce the temperature to 60-70℃, add sulfur and accelerator, mix for 3-4 minutes to ensure that the vulcanizer is evenly dispersed; D. Vulcanization molding: Put the mixed rubber into the mold, heat it to 150-160℃, maintain the pressure for 1 hour to complete the vulcanization reaction, take it out and cool it to room temperature to obtain the finished tire rubber.

[0046] Example 4 A low-resistance and high-wear-resistant tire rubber composition comprises the following raw materials in parts by weight: 55 parts of natural rubber NR, 40 parts of solution-polymerized styrene-butadiene rubber SSBR, 55 parts of modified white carbon black, 4 parts of zinc oxide, 1 part of stearic acid, 2 parts of antioxidant 6PPD, and 3 parts of vulcanization system.

[0047] The vulcanization system includes 2.4 parts of sulfur and 0.6 parts of an accelerator; the accelerator is tetramethylthiuram disulfide TMTD or N-cyclohexyl-2-benzothiazole sulfenamide CBS mixed in a mass ratio of 1:2.

[0048] The preparation method of the modified white carbon black is: (1) adding white carbon black to anhydrous ethanol at a solid-liquid ratio of 1:5, ultrasonically treating for 60 minutes, transferring to a vacuum drying oven, and dehydrating at 60° C. to a moisture content of less than 0.3%, thereby obtaining pretreated white carbon black; (2) mixing an aluminate coupling agent with anhydrous ethanol at a mass ratio of 1:4, stirring at 50° C. for 30 minutes to obtain an aluminate coupling agent hydrolyzate; mixing a silane coupling agent Si75 with an ethanol solution having a mass concentration of 90% at a mass ratio of 1:9, adjusting the pH to 4.5, and hydrolyzing at 40° C. for 1 hour to obtain a silane coupling agent Si75 hydrolyzate; (3) First-stage modification: put the pretreated silica into a stirred reactor, heat it to 80 °C, add 1-butyl-3-methylimidazolium tetrafluoroborate at 10% of the mass of silica, and stir at 2000 rpm for 30 minutes; (4) Second stage modification: Maintain the temperature at 80°C, slowly add aluminate coupling agent hydrolyzate, the amount of aluminate coupling agent hydrolyzate is 10% of the mass of white carbon black, and continue stirring to react for 1 hour; (5) Three-stage modification: the temperature was raised to 100 °C, and the hydrolyzate of silane coupling agent Si75 was added. The amount of silane coupling agent Si75 hydrolyzate was 10% of the mass of white carbon black. The mixture was stirred at 1500 rpm for 45 minutes to complete the condensation reaction. (6) Post-treatment and drying: The three-stage modified slurry is treated by a spray dryer and ground to obtain modified silica.

[0049] Step (1) Ultrasonic treatment power 800 W, frequency 40 kHz.

[0050] During steps (3-5), nitrogen gas was introduced to protect the system and avoid moisture interference.

[0051] The spray drying temperature in step (6) does not exceed 150°C.

[0052] A method for preparing a low-resistance and high-wear-resistant tire rubber composition comprises the following preparation steps: A. Preparation of modified silica; B. Pre-mixing stage: put natural rubber NR and solution polystyrene butadiene rubber SSBR into the internal mixer according to the proportion, control the initial temperature at 80-90℃, and plasticize for 4-6 minutes until the roller is wrapped; add modified white carbon black, zinc oxide, stearic acid and antioxidant 6PPD in sequence, open the cooling water system of the internal mixer, control the mixing temperature at 110-120℃, mix for 8-10 minutes to form a homogeneous rubber compound; discharge the material when the torque curve fluctuation amplitude is ≤5%, and let it stand for 24 hours to release the internal stress; C. Final mixing stage: put the static rubber back into the internal mixer, reduce the temperature to 60-70℃, add sulfur and accelerator, mix for 3-4 minutes to ensure that the vulcanizer is evenly dispersed; D. Vulcanization molding: Put the mixed rubber into the mold, heat it to 150-160℃, maintain the pressure for 1 hour to complete the vulcanization reaction, take it out and cool it to room temperature to obtain the finished tire rubber.

[0053] Example 5 A low-resistance and high-wear-resistant tire rubber composition comprises the following raw materials in parts by weight: 70 parts of natural rubber NR, 30 parts of solution-polymerized styrene-butadiene rubber SSBR, 60 parts of modified white carbon black, 5 parts of zinc oxide, 2 parts of stearic acid, 3 parts of antioxidant 6PPD, and 3.5 parts of a vulcanization system.

[0054] The vulcanization system includes 2.8 parts of sulfur and 0.7 parts of an accelerator; the accelerator is tetramethylthiuram disulfide TMTD.

[0055] The preparation method of the modified white carbon black is: (1) adding white carbon black to anhydrous ethanol at a solid-liquid ratio of 1:5, ultrasonically treating for 60 minutes, transferring to a vacuum drying oven, and dehydrating at 60° C. to a moisture content of less than 0.3%, thereby obtaining pretreated white carbon black; (2) mixing an aluminate coupling agent with anhydrous ethanol at a mass ratio of 1:4, stirring at 50° C. for 30 minutes to obtain an aluminate coupling agent hydrolyzate; mixing a silane coupling agent Si75 with an ethanol solution having a mass concentration of 90% at a mass ratio of 1:9, adjusting the pH to 4.5, and hydrolyzing at 40° C. for 1 hour to obtain a silane coupling agent Si75 hydrolyzate; (3) First-stage modification: put the pretreated silica into a stirred reactor, heat it to 80 °C, add 1-butyl-3-methylimidazolium tetrafluoroborate at 10% of the mass of silica, and stir at 2000 rpm for 30 minutes; (4) Second stage modification: Maintain the temperature at 80°C, slowly add aluminate coupling agent hydrolyzate, the amount of aluminate coupling agent hydrolyzate is 10% of the mass of white carbon black, and continue stirring to react for 1 hour; (5) Three-stage modification: the temperature was raised to 100 °C, and the hydrolyzate of silane coupling agent Si75 was added. The amount of silane coupling agent Si75 hydrolyzate was 10% of the mass of white carbon black. The mixture was stirred at 1500 rpm for 45 minutes to complete the condensation reaction. (6) Post-treatment and drying: The three-stage modified slurry is treated by a spray dryer and ground to obtain modified silica.

[0056] Step (1) Ultrasonic treatment power 800 W, frequency 40 kHz.

[0057] During steps (3-5), nitrogen gas was introduced to protect the system and avoid moisture interference.

[0058] The spray drying temperature in step (6) does not exceed 150°C.

[0059] A method for preparing a low-resistance and high-wear-resistant tire rubber composition comprises the following preparation steps: A. Preparation of modified silica; B. Pre-mixing stage: put natural rubber NR and solution polystyrene butadiene rubber SSBR into the internal mixer according to the proportion, control the initial temperature at 80-90℃, and plasticize for 4-6 minutes until the roller is wrapped; add modified white carbon black, zinc oxide, stearic acid and antioxidant 6PPD in sequence, open the cooling water system of the internal mixer, control the mixing temperature at 110-120℃, mix for 8-10 minutes to form a homogeneous rubber compound; discharge the material when the torque curve fluctuation amplitude is ≤5%, and let it stand for 24 hours to release the internal stress; C. Final mixing stage: put the static rubber back into the internal mixer, reduce the temperature to 60-70℃, add sulfur and accelerator, mix for 3-4 minutes to ensure that the vulcanizer is evenly dispersed; D. Vulcanization molding: Put the mixed rubber into the mold, heat it to 150-160℃, maintain the pressure for 1 hour to complete the vulcanization reaction, take it out and cool it to room temperature to obtain the finished tire rubber.

[0060] Comparative Example 1 In this comparative example, except that the white carbon black is not modified with the ionic liquid (1-butyl-3-methylimidazolium tetrafluoroborate), the other raw materials and preparation process are the same as those in Example 1. That is: A low-resistance and high-wear-resistant tire rubber composition comprises the following raw materials in parts by weight: 50 parts of natural rubber NR, 50 parts of solution-polymerized styrene-butadiene rubber SSBR, 40 parts of modified white carbon black, 3 parts of zinc oxide, 1 part of stearic acid, 1 part of antioxidant 6PPD, and 2.5 parts of a vulcanization system.

[0061] The preparation method of the modified white carbon black is: (1) adding white carbon black to anhydrous ethanol at a solid-liquid ratio of 1:5, ultrasonically treating for 60 minutes, transferring to a vacuum drying oven, and dehydrating at 60° C. to a moisture content of less than 0.3%, thereby obtaining pretreated white carbon black; (2) mixing an aluminate coupling agent with anhydrous ethanol at a mass ratio of 1:4, stirring at 50° C. for 30 minutes to obtain an aluminate coupling agent hydrolyzate; mixing a silane coupling agent Si75 with an ethanol solution having a mass concentration of 90% at a mass ratio of 1:9, adjusting the pH to 4.5, and hydrolyzing at 40° C. for 1 hour to obtain a silane coupling agent Si75 hydrolyzate; (3) First-stage treatment: put the pretreated white carbon black into a stirred reactor, heat it to 80 °C, and stir it at 2000 rpm for 30 minutes; (4) Second stage modification: Maintain the temperature at 80°C, slowly add aluminate coupling agent hydrolyzate, the amount of aluminate coupling agent hydrolyzate is 10% of the mass of white carbon black, and continue stirring to react for 1 hour; (5) Three-stage modification: the temperature was raised to 100 °C, and the hydrolyzate of silane coupling agent Si75 was added. The amount of silane coupling agent Si75 hydrolyzate was 10% of the mass of white carbon black. The mixture was stirred at 1500 rpm for 45 minutes to complete the condensation reaction. (6) Post-treatment and drying: The three-stage modified slurry is treated by a spray dryer and ground to obtain modified silica.

[0062] Comparative Example 2 In this comparative example, except that the white carbon black is not modified with an aluminate coupling agent, the other raw materials and preparation process are the same as those in Example 1. That is: A low-resistance and high-wear-resistant tire rubber composition comprises the following raw materials in parts by weight: 50 parts of natural rubber NR, 50 parts of solution-polymerized styrene-butadiene rubber SSBR, 40 parts of modified white carbon black, 3 parts of zinc oxide, 1 part of stearic acid, 1 part of antioxidant 6PPD, and 2.5 parts of a vulcanization system.

[0063] The preparation method of the modified white carbon black is: (1) adding white carbon black to anhydrous ethanol at a solid-liquid ratio of 1:5, ultrasonically treating for 60 minutes, transferring to a vacuum drying oven, and dehydrating at 60° C. to a moisture content of less than 0.3%, thereby obtaining pretreated white carbon black; (2) mixing the silane coupling agent Si75 with an ethanol solution having a mass concentration of 90% in a mass ratio of 1:9, adjusting the pH to 4.5, and hydrolyzing at 40° C. for 1 hour to obtain a silane coupling agent Si75 hydrolyzate; (3) First-stage modification: put the pretreated silica into a stirred reactor, heat it to 80 °C, add 1-butyl-3-methylimidazolium tetrafluoroborate at 10% of the mass of silica, and stir at 2000 rpm for 30 minutes; (4) Second stage modification: the temperature was raised to 100 °C, and the hydrolyzate of silane coupling agent Si75 was added. The amount of silane coupling agent Si75 hydrolyzate was 10% of the mass of white carbon black. The mixture was stirred at 1500 rpm for 45 minutes to complete the condensation reaction. (5) Post-treatment and drying: The slurry is treated by a spray dryer and ground to obtain modified silica.

[0064] Comparative Example 3 In this comparative example, except that the white carbon black is not modified with the silane coupling agent Si75, the other raw materials and preparation process are the same as those in Example 1. That is: A low-resistance and high-wear-resistant tire rubber composition comprises the following raw materials in parts by weight: 50 parts of natural rubber NR, 50 parts of solution-polymerized styrene-butadiene rubber SSBR, 40 parts of modified white carbon black, 3 parts of zinc oxide, 1 part of stearic acid, 1 part of antioxidant 6PPD, and 2.5 parts of a vulcanization system.

[0065] The preparation method of the modified white carbon black is: (1) adding white carbon black to anhydrous ethanol at a solid-liquid ratio of 1:5, ultrasonically treating for 60 minutes, transferring to a vacuum drying oven, and dehydrating at 60° C. to a moisture content of less than 0.3%, thereby obtaining pretreated white carbon black; (2) mixing an aluminate coupling agent and anhydrous ethanol in a mass ratio of 1:4, stirring at 50° C. for 30 minutes to obtain an aluminate coupling agent hydrolyzate; (3) First-stage modification: put the pretreated silica into a stirred reactor, heat it to 80 °C, add 1-butyl-3-methylimidazolium tetrafluoroborate at 10% of the mass of silica, and stir at 2000 rpm for 30 minutes; (4) Second stage modification: Maintain the temperature at 80°C, slowly add aluminate coupling agent hydrolyzate solution, the amount of aluminate coupling agent hydrolyzate solution is 10% of the mass of silica, and continue stirring to react for 1 hour.

[0066] (5) Post-treatment and drying: The slurry is treated by a spray dryer and ground to obtain modified silica.

[0067] Comparative Example 4 In this comparative example, in addition to changing the modification steps of modified silica, that is, not modifying in steps, a blending modification method is adopted, namely: The preparation method of the modified white carbon black is: (1) adding white carbon black to anhydrous ethanol at a solid-liquid ratio of 1:5, ultrasonically treating for 60 minutes, transferring to a vacuum drying oven, and dehydrating at 60° C. to a moisture content of less than 0.3%, thereby obtaining pretreated white carbon black; (2) mixing an aluminate coupling agent with anhydrous ethanol at a mass ratio of 1:4, stirring at 50° C. for 30 minutes to obtain an aluminate coupling agent hydrolyzate; mixing a silane coupling agent Si75 with an ethanol solution having a mass concentration of 90% at a mass ratio of 1:9, adjusting the pH to 4.5, and hydrolyzing at 40° C. for 1 hour to obtain a silane coupling agent Si75 hydrolyzate; (3) Modification treatment: put the pretreated white carbon black into a stirred reactor, heat it to 80-100°C, add 1-butyl-3-methylimidazolium tetrafluoroborate, aluminate coupling agent hydrolyzate and silane coupling agent Si75 hydrolyzate at 10% of the mass of white carbon black, and stir at 2000 rpm for 135 minutes; (4) Post-treatment and drying: The slurry is treated by a spray dryer and ground to obtain modified silica.

[0068] Comparative Example 5 The tire rubber is prepared according to the prior art CN113929978B.

[0069] Performance Testing The performance tests were conducted on the rubber materials obtained in Examples 1 to 5 of the present invention and Comparative Examples 1 to 5. Five samples were set for each group of experiments, and the results were averaged.

[0070] Tear strength: According to GB / T 529-2008.

[0071] Wear resistance: GB / T1689-2014 Determination of wear resistance of vulcanized rubber (Akron abrasion machine test).

[0072] The dispersibility of white carbon black in the rubber mix is ​​tested using a carbon black dispersometer according to GB / T18251-2000 (where the X value represents the degree of carbon black dispersion, and the Y value represents the dispersion index of large carbon black aggregates in the rubber compound; the larger the X and Y values, the better the carbon black dispersion).

[0073] AFM analysis: The tire rubber sample with a flat surface cut was measured in tapping mode (repulsion), and the dispersion of silica in the tire rubber was analyzed by phase diagram.

[0074] Shore A hardness is tested according to GB / T531-2008.

[0075] The dynamic mechanical properties of the tread rubber were tested by dynamic mechanical thermal analysis (DMTA) with a temperature sweep range of ‑10°C to 70°C, a heating rate of 5°C / min, a frequency of 10 Hz, and a strain of 0.20%.

[0076] Table 1 Performance test results From the data in the table, we can see that compared with the comparative example and the prior art, the tire tread rubber in the embodiment shows better comprehensive performance. The Shore A hardness of Examples 1 to 5 is moderate, while the tensile strength and elongation at break are excellent, showing good mechanical properties. The carbon black dispersibility in the embodiments is higher than that in the comparative example. The increase in the X value and the Y value proves that the carbon black is more evenly dispersed in the rubber compound. The Akron abrasion data also shows that the wear resistance of the embodiment is significantly better than that of the comparative example, which is of great significance for extending the service life of the tire. For Comparative Examples 1-4, in which the carbon black modification method is changed, the three-stage modification effect of ionic liquid physical coating → aluminate coupling agent chemical bonding → silane reinforcement cross-linking is weakened, so the dispersion effect of white carbon black decreases, which is externalized as a decrease in the comprehensive performance of the tire rubber. From the AFM phase diagram ( Figure 1 ) It can also be seen that different colors indicate differences in modulus. The dispersibility of silica can be determined based on the differences in modulus of silica, rubber and other raw materials. Figure 1 It can be seen that the carbon black dispersion distribution of the embodiment of the present invention is more uniform, showing excellent dispersion performance, and the dispersion effect of the comparative example is significantly improved. In summary, the optimization of the tire tread rubber formula in the embodiment brings about significant performance improvement, which is not only reflected in mechanical properties, but also includes the reduction of rolling resistance. It is very beneficial to the use demand of new energy vehicle tires and has broad market application prospects.

[0077] It should be noted that the above embodiments are only partial embodiments of the preferred methods of implementing the present invention, rather than all embodiments. Obviously, based on the above embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

Claims

1. A low resistance and high wear resistant tire rubber composition, characterized in that: The invention comprises the following raw materials in parts by weight: 50-70 parts of natural rubber NR, 30-50 parts of solution-polymerized styrene-butadiene rubber SSBR, 40-60 parts of modified white carbon black, 3-5 parts of zinc oxide, 1-2 parts of stearic acid, 1-3 parts of antioxidant 6PPD and 2.5-3.5 parts of vulcanization system.

2. The low resistance and high wear resistant tire rubber composition according to claim 1, characterized in that: The vulcanization system comprises 2.0-2.8 parts of sulfur and 0.5-0.7 parts of an accelerator; the accelerator is one or more of tetramethylthiuram disulfide TMTD or N-cyclohexyl-2-benzothiazole sulfenamide CBS.

3. The low resistance and high wear resistant tire rubber composition according to claim 1, characterized in that: The preparation method of the modified white carbon black is: (1) adding white carbon black to anhydrous ethanol at a solid-liquid ratio of 1:5, ultrasonically treating for 60 minutes, transferring to a vacuum drying oven, and dehydrating at 60° C. to a moisture content of less than 0.3%, thereby obtaining pretreated white carbon black; (2) mixing an aluminate coupling agent with anhydrous ethanol at a mass ratio of 1:4, stirring at 50° C. for 30 minutes to obtain an aluminate coupling agent hydrolyzate; mixing a silane coupling agent Si75 with an ethanol solution having a mass concentration of 90% at a mass ratio of 1:9, adjusting the pH to 4.5, and hydrolyzing at 40° C. for 1 hour to obtain a silane coupling agent Si75 hydrolyzate; (3) First-stage modification: put the pretreated silica into a stirred reactor, heat it to 80 °C, add 1-butyl-3-methylimidazolium tetrafluoroborate at 10% of the mass of silica, and stir at 2000 rpm for 30 minutes; (4) Second stage modification: Maintain the temperature at 80°C, slowly add aluminate coupling agent hydrolyzate, the amount of aluminate coupling agent hydrolyzate is 10% of the mass of white carbon black, and continue stirring to react for 1 hour; (5) Three-stage modification: raise the temperature to 100°C, add silane coupling agent Si75 hydrolyzate, the amount of silane coupling agent Si75 hydrolyzate is 10% of the mass of white carbon black, stir at 1500 rpm for 45 minutes to complete the condensation reaction; (6) Post-treatment and drying: The three-stage modified slurry is treated by a spray dryer and ground to obtain modified silica.

4. The low resistance and high wear resistant tire rubber composition according to claim 3, characterized in that: Step (1) Ultrasonic treatment power 800 W, frequency 40 kHz.

5. The low resistance and high wear resistant tire rubber composition according to claim 3, characterized in that: The spray drying temperature in step (6) does not exceed 150°C.

6. A method for preparing the low resistance and high wear resistant tire rubber composition according to any one of claims 1 to 5, characterized in that: The method comprises the following preparation steps: A. Preparation of modified silica; B. Pre-mixing stage: put natural rubber NR and solution polystyrene butadiene rubber SSBR into the internal mixer according to the proportion, control the initial temperature at 80-90℃, and plasticize for 4-6 minutes until the roller is wrapped; add modified white carbon black, zinc oxide, stearic acid and antioxidant 6PPD in sequence, open the cooling water system of the internal mixer, control the mixing temperature at 110-120℃, mix for 8-10 minutes to form a homogeneous rubber compound; discharge the material when the torque curve fluctuation amplitude is ≤5%, and let it stand for 24 hours to release the internal stress; C. Final mixing stage: put the static rubber back into the internal mixer, reduce the temperature to 60-70℃, add sulfur and accelerator, mix for 3-4 minutes to ensure that the vulcanizer is evenly dispersed; D. Vulcanization molding: Put the mixed rubber into the mold, heat it to 150-160℃, maintain the pressure for 1 hour to complete the vulcanization reaction, take it out and cool it to room temperature to obtain the finished tire rubber.

7. A low resistance and high wear resistant tire rubber composition according to any one of claims 1 to 5, characterized in that: The composition is suitable for new energy vehicle tires.

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