Wear-resistant and high-temperature-resistant tread rubber composition and mixing method thereof

Abstract

The invention relates to the technical field of tire rubber manufacturing, and discloses a wear-resistant and high-temperature-resistant tread rubber composition and a mixing method thereof.The rubber composition is prepared from, by weight, 65-80 parts of rubber, 40-60 parts of filler A, 3-6 parts of an activating agent, 2-4 parts of a vulcanizing agent, 2-5 parts of an anti-aging agent and 0.5-1.5 parts of tear-resistant resin through mixing, 15-45 parts of a nano reinforced composite material and 0.5-2 parts of microcrystalline wax; the nano reinforced composite material is prepared by mixing butadiene rubber, a filler B, organic sulfide and dihydrazide. Through non-homogeneous distribution of the filler, the nano reinforced composite material can absorb a large amount of energy in the stretching process, and the high temperature resistance and wear resistance of the tread rubber composition can be obviously improved.

Description

Technical Field

[0001] The invention relates to the technical field of tire rubber manufacturing, in particular to a wear-resistant and high-temperature-resistant tread rubber composition and a mixing method thereof. Background Art

[0002] The tread rubber is located on the outermost layer of the tire and is in direct contact with the road surface. It is related to the driving safety and performance of the vehicle. The main function of the tread rubber is to provide good grip and wear resistance to ensure the safe driving of the vehicle under various road conditions. The design and material selection of the tread rubber are directly related to the vehicle's handling, braking performance and fuel efficiency.

[0003] The Chinese invention patent applied by the applicant (publication number: CN115572416B, publication date: 2023-09-08) is a high-temperature resistant tire tread rubber composed of the following materials by weight: 40% to 60% natural rubber, 6% to 18% polybutadiene, 25% to 33% filler, 1% to 7% activator, 0.2% to 2% microcrystalline wax, 1% to 4% antioxidant, 0.3% to 1.2% vulcanizer, 0.3% to 2% accelerator, and 0% to 0.2% anti-scorch agent. The prepared tread rubber composition has a high storage modulus E' at low strain, and the modulus at high temperature is significantly improved, the wear resistance is improved, and the rolling resistance is reduced, thereby increasing the service life and mileage of the tire.

[0004] The wear resistance and other properties of tires are closely related to the tread rubber composition, and wear resistance is also an important property of tires. The tire is driven at a high temperature of 60-80°C. As the temperature rises to 60°C, the mechanical properties of the tread rubber composition decrease by more than 30%, resulting in a decrease in the wear resistance of the tread rubber and an increase in heat generation. Therefore, how to optimize the formula of the rubber composition and prepare a wear-resistant and high-temperature resistant tire is an urgent problem to be solved by those skilled in the art. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present invention provides a wear-resistant and high-temperature resistant tread rubber composition and a mixing method thereof, which improves the modulus and mechanical properties of the rubber composition at high temperatures by using a nano-reinforced wear-resistant composite material through the inhomogeneous distribution of fillers, thereby further improving the wear resistance of the rubber composition.

[0006] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions: A wear-resistant and high-temperature-resistant tread rubber composition, wherein the rubber composition is prepared by mixing the following raw materials in parts by weight: Rubber A 65-80 parts, Filler A 40-60 parts, Activator 3.0-6.0 parts, 2.0-4.0 parts of vulcanizing agent, Anti-aging agent 2.0-5.0 parts, 15-45 parts of nano-reinforced composite materials, The rubber is natural rubber and / or synthetic isoprene rubber, and the filler A is carbon black and / or white carbon black; The nano-reinforced composite material is prepared by mixing the following raw materials in parts by weight: Rubber B 20-40 parts, Filler B 1.0-10 parts, 1.0-4.0 parts of organosilicon polysulfide compounds, 0.4-2.0 parts of dihydrazide compound; The rubber B is butadiene rubber; the total weight of the rubber A + the rubber B is 100 parts by weight, and the filler B is one or more of carbon nanotubes, graphene, and carbon black.

[0007] Preferably, the rubber composition is prepared by mixing the following raw materials in parts by weight: Rubber A 70-80 parts, Filler A 50-60 parts, Activator 4.0-6.0 parts, 2.0-3.0 parts of vulcanizing agent, Anti-aging agent 2.0-4.0 parts, 25-40 parts of nano-reinforced composite materials, The nano-reinforced composite material is prepared by mixing the following raw materials by weight: Rubber B 20-35 parts, Filler B 2.0-5.0 parts, 1.0-2.5 parts of organosilicon polysulfide compounds, 0.5-1.5 parts of dihydrazide compound.

[0008] Preferably, the carbon black in the filler A is one or two of N375, N330, N339, N347, and N326.

[0009] Preferably, the carbon nanotubes in the filler B are in array form, the carbon black is N375, N330, N339, N347 or N326, and the graphene is 2-10 layers of graphene oxide.

[0010] Preferably, the organosilicon polysulfide is selected from one or more of γ-mercaptopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, bis(3-mercaptopropyl)tetrasulfide, bis(3-mercaptopropyl)disulfide, mercaptoethyltriethoxysilane, mercaptopropylsiloxane copolymer, methylmercaptosilane, dimercaptoethylsilane, tetra(mercaptopropyl)silane and bis(γ-triethoxysilylpropyl)sulfide.

[0011] Preferably, the activator is selected from one or more of zinc oxide, stearic acid, and zinc stearate; and / or, the antioxidant is selected from one or more of antioxidant 4010, antioxidant 4020, antioxidant RD, 2-mercaptobenzothiazole, and antioxidant TMQ; And / or, the vulcanizing agent is selected from one or more of sulfur, dicumyl peroxide, vulcanization accelerator NS, vulcanization accelerator CZ, and tetramethylthiuram disulfide.

[0012] Preferably, the mixing raw materials of the rubber composition further include 0.5-1.5 parts of tear-resistant resin and 0.5-2 parts of microcrystalline wax.

[0013] Preferably, the tear-resistant resin is one or more of polycyclopentadiene resin, C5 modified resin and C9 modified resin.

[0014] Preferably, the preparation method of the nano-reinforced wear-resistant composite material comprises the following steps: starting an internal mixer, setting the speed to 30-45 rpm, adding butadiene rubber, filler and organosilicon polysulfide compound, mixing for 25-40 seconds, adding dihydrazide compound, continuing mixing for 1-2.5 minutes, debonding, and obtaining the nano-reinforced composite material.

[0015] Furthermore, the present invention also provides a method for preparing the rubber composition, comprising the following steps: 1) First stage mixing: start the internal mixer, set the speed to 45-55 rpm, add rubber, filler A, activator, antioxidant, tear-resistant resin, microcrystalline wax, mix for 30-50 seconds, remove the plug and mix for 20-30 seconds, remove the plug and mix until the temperature reaches 150-165°C to discharge the rubber, and obtain masterbatch 1; 2) Second stage mixing: Start the internal mixer, set the speed to 25-35 rpm, add masterbatch 1 and nano-reinforced composite material, mix for 30-50 seconds, remove the plug and mix for 20-30 seconds, remove the plug and mix until the temperature reaches 135-145°C to discharge the glue, and obtain masterbatch 2; 3) Vulcanization: Start the internal mixer, set the speed to 25-35 rpm, first add masterbatch 2 and vulcanizer, mix for 30-50 seconds, remove the bolt and mix for 20-30 seconds, remove the bolt and mix until the temperature reaches 105-115°C to discharge the rubber, and obtain a wear-resistant and high-temperature resistant rubber composition.

[0016] The present invention adopts the above technical solution, and through the inhomogeneous distribution of fillers, the nano-reinforced composite material can absorb a large amount of energy during the stretching process, which can significantly improve the high temperature resistance and wear resistance of the tread rubber composition. The following significant technical effects are shown: 1. Significantly improved wear resistance: The present invention optimizes the distribution characteristics of fillers in the rubber matrix by introducing nano-reinforced composite materials. During the stretching process, the nano-fillers can effectively absorb strain energy and significantly improve the anti-destruction ability of the rubber material, thereby enhancing the wear resistance of the tread rubber and extending the service life of the tire.

[0017] 2. Optimized high-temperature performance: Nano-reinforced composite materials provide excellent modulus retention under high-temperature conditions, ensuring that the tread rubber has good mechanical properties in an operating environment of 60-80°C. The drop in the material's tear strength and dynamic modulus at high temperatures is more than 30% less than that of traditional materials, greatly improving the high-temperature stability and safety of the tire.

[0018] 3. Enhanced dynamic fatigue performance: Through the inhomogeneous distribution design of fillers, the rubber composition of the present invention effectively reduces the heat generation during dynamic driving and significantly delays the aging process of rubber. The anti-fatigue performance of rubber under dynamic compression deformation (>10 Hz) is enhanced, which is particularly suitable for high-speed driving scenarios.

[0019] 4. Balance of mechanical properties: Through the chemical modification of dihydrazide compounds, the interfacial bonding force between the nanofiller and the rubber matrix is ​​enhanced, while the activity of the terminal groups of the rubber is optimized, further improving the strength and flexibility of the rubber, while taking into account the balance between tensile strength, wear resistance and dynamic properties.

[0020] 5. Significantly reduced heat generation: The dihydrazide compound can react chemically with the aldehyde, carboxyl and carbonyl groups at the end of the rubber, effectively reducing the activity of the free radical end, and reducing the internal friction and heat generation of the rubber during dynamic deformation. Compared with traditional rubber compositions, the temperature rise of the material of the present invention is reduced by 20%-30%, further improving the durability of the tire.

[0021] 6. Synergistic improvement of multiple performances: The present invention not only improves wear resistance and high temperature resistance, but also successfully solves the contradiction between grip and rolling resistance in traditional rubber formulas. The tire prepared using the rubber composition of the present invention not only has higher driving safety, but also significantly reduces rolling resistance and improves fuel efficiency.

[0022] In summary, the present invention not only significantly improves the wear resistance, high temperature resistance and dynamic fatigue performance of the tire through material innovation and process optimization, but also achieves the synergistic improvement of multiple performances, providing a new solution for the preparation of tire rubber. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of a SEM scanning electron microscope of the rubber composition of Example 1, and the black part in the figure is a nano-reinforced composite material.

[0024] Figure 2 This is a schematic diagram of the SEM scanning electron microscope of the rubber composition of Comparative Example 1. DETAILED DESCRIPTION

[0025] 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 described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] The formulations of the embodiments and comparative examples are shown in Table 1.

[0027] Table 1

[0028] The formula of nano-reinforced composite materials is shown in Table 2.

[0029] Table 2

[0030] Note: 1. Natural rubber, Thailand No. 20 standard rubber; 2. Butadiene rubber, neodymium butadiene BR-544 NP from Nizhnekamsk, Russia; 3. Multi-walled carbon nanotubes, a product of Shandong Dazhan Nanomaterials Co., Ltd.; 4. Sebacic acid dihydrazide compound, provided by Harbin Quaker New Materials Co., Ltd.; 5. Organosilicon polysulfide, bis-[γ-(triethoxysilyl)propyl] tetrasulfide produced by Jiangxi Hongbai New Materials Co., Ltd.; 6. Other additives are commercially available products.

[0031] The preparation method of the nano-reinforced composite material is as follows: The internal mixer was started and the speed was set to 40 rpm. Butadiene rubber, filler B and organosilicon polysulfide were first added and mixed for 30 seconds. The dihydrazide compound was added and mixed for 1.5 minutes. The mixture was discharged to obtain a nano-reinforced composite material.

[0032] The preparation method of the embodiment is as follows: 1) First stage mixing: start the internal mixer, set the speed to 50 rpm, add natural rubber, filler A, activator, antioxidant, tear-resistant resin, microcrystalline wax, mix for 40 seconds, remove the plug and mix for 25 seconds, remove the plug and mix until the temperature reaches 160°C to discharge the rubber, and obtain masterbatch 1; 2) Second stage mixing: Start the internal mixer, set the speed to 30 rpm, add masterbatch 1 and nano-reinforced composite material, mix for 35 seconds, remove the plug and mix for 20 seconds, remove the plug and mix until the glue is discharged at 140°C to obtain masterbatch 2; 3) Adding vulcanization: start the internal mixer, set the speed to 25 rpm, add masterbatch 2 and vulcanizer, mix for 35 seconds, mix for 30 seconds with the bolt raised and the bolt pressed, mix until the temperature reaches 112°C for rubber discharge, and obtain a wear-resistant and high-temperature resistant rubber composition.

[0033] The preparation method of the comparative example is as follows: 1) First-stage mixing: start the internal mixer, set the speed to 50 rpm, add all materials except the vulcanizing agent, dihydrazide compound and organic vulcanizing agent, mix for 40 seconds, remove the plug and mix for 25 seconds, remove the plug and mix until the temperature reaches 160°C to discharge the glue, and obtain masterbatch 1; 2) Second stage mixing: Start the internal mixer, set the speed to 30 rpm, add masterbatch 1, dihydrazide compound and organic vulcanizing agent, mix for 35 seconds, mix for 20 seconds with the plug lifted, and mix until the temperature reaches 140°C to discharge the glue, to obtain masterbatch 2; 3) Vulcanization: start the internal mixer, set the speed to 25 rpm, add masterbatch 2 and vulcanizer, mix for 35 seconds, mix for 30 seconds with the bolt raised and the bolt pressed, mix until the temperature reaches 112°C for rubber discharge, and obtain a rubber composition.

[0034] The rubber compositions obtained in the examples and comparative examples were subjected to performance tests, and the test results are shown in Table 3.

[0035] Table 3

[0036] From the above examples 1 and 2 and comparative examples 1 and 2, it can be seen that the use of nano-reinforced composite materials can significantly improve the high temperature resistance of the tread rubber composition. Under high temperature 100°C stretching, M300 is increased by 29.4% and 26.7%; E' at 60°C is increased by 19.3% and 16.4% respectively; and wear resistance is increased by 41% and 47.5% respectively. It can be seen that the tread rubber composition prepared by the present invention has wear resistance and high temperature resistance.

[0037] The above is a description of the embodiments of the present invention. Through the above description of the disclosed embodiments, professionals and technicians in the field can implement or use the present invention. Various modifications to these embodiments will be apparent to professionals and technicians 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 these embodiments shown in this article, but will conform to the widest range consistent with the principles and novelties disclosed herein.

Claims

1. A wear-resistant and high-temperature resistant tread rubber composition, characterized in that: The rubber composition is prepared by mixing the following raw materials in parts by weight: Rubber A 65-80 parts, Filler A 40-60 parts, Activator 3.0-6.0 parts, 2.0-4.0 parts of vulcanizing agent, Anti-aging agent 2.0-5.0 parts, 15-45 parts of nano-reinforced composite materials, The rubber is natural rubber and / or synthetic isoprene rubber, and the filler A is carbon black and / or white carbon black; The nano-reinforced composite material is prepared by mixing the following raw materials by weight: Rubber B 20-40 parts, Filler B 1.0-10 parts, 1.0-4.0 parts of organosilicon polysulfide compounds, 0.4-2.0 parts of dihydrazide compound; The rubber B is butadiene rubber; the total weight of the rubber A + the rubber B is 100 parts by weight, and the filler B is one or more of carbon nanotubes, graphene, and carbon black.

2. The wear-resistant and high-temperature-resistant tread rubber composition according to claim 1, characterized in that: The rubber composition is prepared by mixing the following raw materials in parts by weight: Rubber A 70-80 parts, Filler A 50-60 parts, Activator 4.0-6.0 parts, 2.0-3.0 parts of vulcanizing agent, Anti-aging agent 2.0-4.0 parts, Nano-reinforced composites 25-40, The nano-reinforced composite material is prepared by mixing the following raw materials by weight: Rubber B 20-35 parts, Filler B 2.0-5.0 parts, 1.0-2.5 parts of organosilicon polysulfide compounds, 0.5-1.5 parts of dihydrazide compound.

3. A wear-resistant and high temperature resistant tread rubber composition according to claim 1 or 2, characterized in that: The carbon black in the filler A is one or two of N375, N330, N339, N347, and N326; And / or, the carbon nanotubes in the filler B are in array form, the carbon black is N375, N330, N339, N347 or N326, and the graphene is 2-10 layers of graphene oxide.

4. A wear-resistant and high temperature resistant tread rubber composition according to claim 1 or 2, characterized in that: The organosilicon polysulfide is selected from one or more of γ-mercaptopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, bis(3-mercaptopropyl)tetrasulfide, bis(3-mercaptopropyl)disulfide, mercaptoethyltriethoxysilane, mercaptopropylsiloxane copolymer, methylmercaptosilane, dimercaptoethylsilane, tetra(mercaptopropyl)silane and bis(γ-triethoxysilylpropyl)sulfide.

5. A wear-resistant and high temperature resistant tread rubber composition according to claim 1 or 2, characterized in that: The activator is selected from one or more of zinc oxide, stearic acid, and zinc stearate; and / or, the antioxidant is selected from one or more of antioxidant 4010, antioxidant 4020, antioxidant RD, 2-mercaptobenzothiazole, and antioxidant TMQ; And / or, the vulcanizing agent is selected from one or more of sulfur, dicumyl peroxide, vulcanization accelerator NS, vulcanization accelerator CZ, and tetramethylthiuram disulfide.

6. A wear-resistant and high temperature resistant tread rubber composition according to claim 1 or 2, characterized in that: The mixed raw materials of the rubber composition also include 0.5-1.5 parts of tear-resistant resin and 0.5-2 parts of microcrystalline wax.

7. The wear-resistant and high-temperature-resistant tread rubber composition according to claim 6, characterized in that: The tear-resistant resin is one or more of polycyclopentadiene resin, C5 modified resin and C9 modified resin.

8. The wear-resistant and high-temperature-resistant tread rubber composition according to claim 1 or 2, characterized in that: The preparation method of the nano-enhanced wear-resistant composite material comprises the following steps: starting an internal mixer, setting the speed to 30-45 revolutions, adding natural rubber, filler and organosilicon polysulfide, mixing for 25-40 seconds, adding a dihydrazide compound, continuing mixing for 1-2.5 minutes, and removing the binder to obtain the nano-enhanced composite material.

9. A mixing method for a wear-resistant and high-temperature resistant tread rubber composition according to any one of claims 1 to 8, characterized in that: The following steps are involved: 1) First stage mixing: start the internal mixer, set the speed to 45-55 rpm, add rubber, filler A, activator, antioxidant, tear-resistant resin, microcrystalline wax, mix for 30-50 seconds, remove the plug and mix for 20-30 seconds, remove the plug and mix until the temperature reaches 150-165°C to discharge the rubber, and obtain masterbatch 1; 2) Second stage mixing: Start the internal mixer, set the speed to 25-35 rpm, add masterbatch 1 and nano-reinforced composite material, mix for 30-50 seconds, remove the plug and mix for 20-30 seconds, remove the plug and mix until the temperature reaches 135-145°C to discharge the glue, and obtain masterbatch 2; 3) Vulcanization: Start the internal mixer, set the speed to 25-35 rpm, add masterbatch 2 and vulcanizer, mix for 30-50 seconds, remove the bolt and mix for 20-30 seconds, remove the bolt and mix until the temperature reaches 105-115°C to discharge the rubber, and obtain a wear-resistant and high-temperature resistant rubber composition.

10. A wear-resistant and high-temperature resistant tire, characterized in that: The tread of the tire is prepared by vulcanizing the rubber composition obtained according to any one of claims 1 to 8.

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