A Lightweight, High-Strength and Low-Rolling-Resistance Tire for New Energy Vehicles and Its Preparation Method

Abstract

The present invention provides a lightweight, high-strength and low-rolling-resistance tire for new energy vehicles and a preparation method thereof, relating to the technical field of tires. The lightweight, high-strength and low-rolling-resistance tire for new energy vehicles of the present invention comprises a tread and a sidewall; wherein, both the tread and the sidewall are composed of tread rubber containing the following components: low-epoxy-degree epoxidized solution-polymerized styrene-butadiene rubber with an epoxy degree of 6.5-8.4%, high-epoxy-degree epoxidized solution-polymerized styrene-butadiene rubber with an epoxy degree of 21.2-23.7%, natural rubber, carbon black, silica and rubber additives. By optimizing the formula of the tread rubber, the present invention not only realizes the lightweight of the tire, effectively reduces the rolling resistance of the tire, but also improves the strength and anti-aging performance of the tire, and prolongs the service life of the tire.

Description

Technical Field

[0001] The present invention relates to the technical field of tires, and particularly to a lightweight, high-strength and low-rolling-resistance tire for new energy vehicles and a preparation method thereof. Background Art

[0002] In recent years, the development of new energy vehicles has been increasingly rapid. People have paid more and more attention to the driving safety, energy conservation, comfort, etc. of vehicles. As the only component of a vehicle that contacts the ground, tires are required to have the following specific characteristics: lightweight, low rolling resistance, low noise, high wet grip and high load-bearing performance, low rolling resistance, high wear resistance, etc.

[0003] When a vehicle is driving, various driving resistances will be generated, and a part of them is rolling resistance. The energy consumption required for the rolling resistance of vehicle tires accounts for about 20% of the fuel consumption of the whole vehicle. Reducing the rolling resistance of tires can significantly reduce fuel consumption. In order to reduce the rolling resistance of tires, lightweight tires have been developed. At present, the main method to make tires lightweight is to change the tread and sidewall rubber compounds of the tires. For example, the amount of rubber used in the rubber compound can be reduced, but reducing the amount of rubber used will affect the durability of the tires, and the rigidity and handling stability of the tires will also decrease; it can also be achieved by reducing the use of reinforcing fillers such as carbon black. Adding reinforcing fillers such as carbon black to rubber can improve the strength, wear resistance, etc. of rubber, but it will increase the mass of the tires, and the large friction between carbon blacks and between carbon black and rubber will also cause the rolling resistance to increase. Therefore, reducing the use of carbon black can significantly reduce the rolling resistance, but it will cause the strength, wear resistance, etc. of rubber to decline. In addition, the rolling resistance of tires can also be reduced by increasing the amount of sulfur used, but increasing the amount of sulfur used will also cause the decline of aging resistance performance.

[0004] Therefore, it is necessary to provide a new energy vehicle tire with lightweight, high strength and low rolling resistance. Summary of the Invention

[0005] Aiming at the deficiencies of the prior art, the present invention provides a lightweight, high-strength and low-rolling-resistance tire for new energy vehicles and a preparation method thereof.

[0006] To achieve the above object, the technical solutions adopted by the present invention are as follows:

[0007] A lightweight, high-strength and low-rolling-resistance tire for new energy vehicles, including a tread and a sidewall; wherein,

[0008] Both the tread and the sidewall are composed of a tread rubber containing the following components: low-epoxy epoxidized solution-polymerized styrene-butadiene rubber with an epoxy degree of 6.5-8.4%, high-epoxy epoxidized solution-polymerized styrene-butadiene rubber with an epoxy degree of 21.2-23.7%, natural rubber, carbon black, silica and rubber additives.

[0009] Further, the epoxidation degree of the high-epoxidation-degree epoxidized solution-polymerized styrene-butadiene rubber is 22.4%; the epoxidation degree of the low-epoxidation-degree epoxidized solution-polymerized styrene-butadiene rubber is 7.1%.

[0010] Further, the mass ratio of the low-epoxidation-degree epoxidized solution-polymerized styrene-butadiene rubber to the high-epoxidation-degree epoxidized solution-polymerized styrene-butadiene rubber is (50-70):(10-20); preferably, the mass ratio of the low-epoxidation-degree epoxidized solution-polymerized styrene-butadiene rubber to the high-epoxidation-degree epoxidized solution-polymerized styrene-butadiene rubber is 60:18.

[0011] Further, the rubber additive includes aromatic oil, stearic acid, zinc oxide, sulfur, accelerator, antioxidant and scorch retarder.

[0012] Further, the tread rubber comprises the following components in parts by weight: 70-80 parts of low-epoxidation-degree epoxidized solution-polymerized styrene-butadiene rubber and high-epoxidation-degree epoxidized solution-polymerized styrene-butadiene rubber, 20-30 parts of natural rubber, 25-40 parts of carbon black, 15-25 parts of white carbon black, 1-10 parts of aromatic oil, 0.5-6 parts of stearic acid, 0.5-8 parts of zinc oxide, 0.2-6 parts of sulfur, 0.3-5 parts of accelerator, 0.5-8 parts of antioxidant and 0.5-6 parts of scorch retarder.

[0013] Preferably, the tread rubber comprises the following components in parts by weight: 78 parts of low-epoxidation-degree epoxidized solution-polymerized styrene-butadiene rubber and high-epoxidation-degree epoxidized solution-polymerized styrene-butadiene rubber, 22 parts of natural rubber, 30 parts of carbon black, 20 parts of white carbon black, 5 parts of aromatic oil, 3 parts of stearic acid, 5 parts of zinc oxide, 3 parts of sulfur, 2 parts of accelerator, 5 parts of antioxidant and 3 parts of scorch retarder.

[0014] Further, there are 5 tread blocks and 4 longitudinal grooves provided on the tread; the 5 tread blocks are respectively a first shoulder tread block, a first inner tread block, a central tread block, a second inner tread block and a second shoulder tread block; a longitudinal groove I is formed between the first shoulder tread block and the first inner tread block, a longitudinal groove II is formed between the first inner tread block and the central tread block, a longitudinal groove III is formed between the central tread block and the second inner tread block, and a longitudinal groove IV is formed between the second inner tread block and the second shoulder tread block.

[0015] Preferably, the widths of the central tread block, the first inner tread block and the second inner tread block are respectively 13±1.5% of the ground contact width TDW, 12±1.5% of the ground contact width TDW, and 12.5±1.5% of the ground contact width TDW; the widths of the first shoulder tread block and the second shoulder tread block are respectively 20±2% of the ground contact width TDW, 20±2% of the ground contact width TDW.

[0016] Preferably, the widths of the 4 longitudinal grooves are all 5%±1 of the ground contact width TDW.

[0017] Preferably, central steel sheet transverse grooves and central steel sheets which are arranged at intervals and have the same inclination direction are provided on the central tread block; both ends of each central steel sheet transverse groove are respectively communicated with the longitudinal grooves II and III on both sides, one end of each central steel sheet is communicated with the longitudinal groove II, and the other end extends to the vicinity of the tread center line; the included angle between the arrangement direction of the central steel sheet transverse groove and the tread center line is 65±3°.

[0018] Preferably, first inner steel sheet transverse grooves, first inner steel sheets and second inner steel sheets which are arranged at intervals and have the same inclination direction are provided on the first inner tread block; both ends of each first inner steel sheet transverse groove are respectively communicated with the longitudinal grooves I and II on both sides, the outer side of each first inner steel sheet is communicated with the longitudinal groove I, the other side extends to the vicinity of the center line of the first inner tread block, the inner end of each second inner steel sheet is communicated with the longitudinal groove II7, and the other end extends to the vicinity of the center line of the first inner tread block; the included angle between the arrangement direction of the first inner steel sheet transverse groove and the tread center line is 68±5°.

[0019] Preferably, the second inner tread block is arranged in a central symmetry arrangement with respect to the first inner tread block.

[0020] Preferably, first shoulder steel sheet transverse grooves and first shoulder steel sheets which are arranged at intervals and have the same inclination direction are provided on the first shoulder tread block; each first shoulder steel sheet penetrates through the first shoulder tread block, only the inner end of each first shoulder steel sheet is communicated with the longitudinal groove I, and the length of each first shoulder steel sheet is less than that of the first shoulder steel sheet transverse groove; the included angle between the arrangement direction of the first shoulder steel sheet transverse groove and the tread center line is 85±3°.

[0021] Preferably, the second shoulder tread block is arranged in a central symmetry arrangement with respect to the first shoulder tread block.

[0022] Preferably, the tread pattern pitch is 25-35 cm.

[0023] In a further embodiment, sepiolite fiber modified is used to replace silica in the tread rubber, and the addition amount of the sepiolite fiber modified is 5-9% of the total weight of the rubber components (the rubber components are low-epoxy epoxidized solution styrene butadiene rubber, high-epoxy epoxidized solution styrene butadiene rubber and natural rubber), and the sepiolite fiber modified is obtained by modifying sepiolite fiber with a secondary amino group-containing silane coupling agent. The sepiolite fiber modified is specifically prepared by the following method:

[0024] The sepiolite fiber is soaked in an acid solution and soaked at 60-70°C for 6-8 h. After soaking, suction filtration is carried out, and after drying, it is dispersed in DMF, a secondary amino group-containing silane coupling agent is added, and the reaction is carried out at 70-80°C for 2-3 h. Then suction filtration is carried out, and it is washed with absolute ethanol and deionized water and dried to obtain the sepiolite fiber modified.

[0025] Preferably, the acid solution is at least one of sulfuric acid, hydrochloric acid, and nitric acid, and the mass fraction of the acid solution is 10-15%.

[0026] Preferably, the secondary amino group-containing silane coupling agent is bis(3-trimethoxysilylpropyl)amine and / or bis(3-triethoxysilylpropyl)amine.

[0027] Preferably, the dosage of the secondary amino group-containing silane coupling agent is 5-8.5% of the pretreated sepiolite fiber.

[0028] The present invention also provides a preparation method of a lightweight, high-strength and low-rolling resistance tire for new energy vehicles, comprising the following steps:

[0029] After the above tread rubber is kneaded, a kneaded rubber is obtained, and then a tread and a tire side are made according to the tread pattern setting, and a lightweight, high-strength and low-rolling resistance tire for new energy vehicles is prepared.

[0030] Further, the preparation steps of the kneaded rubber include:

[0031] (1) Add low-epoxy epoxidized solution-polymerized styrene-butadiene rubber, high-epoxy epoxidized solution-polymerized styrene-butadiene rubber, and natural rubber into a mixer, and knead at a temperature of 135-160 °C to obtain a first-stage masterbatch;

[0032] (2) Add zinc oxide, stearic acid, paraffin wax, and antioxidant, and knead at a temperature of 120-155 °C to obtain a second-stage masterbatch;

[0033] (3) Add the second-stage masterbatch, sulfur, accelerator, and scorch retarder, and knead at a temperature of 140-150 °C to obtain the kneaded rubber.

[0034] Preferably, the preparation steps of the kneaded rubber include:

[0035] (1) Add low-epoxy epoxidized solution-polymerized styrene-butadiene rubber, high-epoxy epoxidized solution-polymerized styrene-butadiene rubber, and natural rubber into a mixer, press the upper plug for 30-40 s, raise the upper plug and then press for 10-20 s, raise the upper plug and add carbon black and white carbon black under pressure for 15-25 s at 135-145 °C, raise the upper plug and then press for 10-18 s, raise the upper plug at a temperature of 150-160 °C, and open the discharge door to obtain a first-stage masterbatch;

[0036] (2) Add zinc oxide, stearic acid, paraffin wax, and antioxidant into the mixer, press the upper plug for 25-35 s, raise the upper plug and then press for 18-25 s at 120-130 °C, raise the upper plug and then press for 10-20 s, raise the upper plug at 145-155 °C, and open the discharge door to obtain a second-stage masterbatch;

[0037] (3) Add sulfur, accelerator, and scorch retarder into the internal mixer, apply the upper plug for 20 - 30 s, raise the upper plug and then apply pressure for 15 - 25 s, raise the upper plug again and apply pressure for 10 - 20 s, raise the upper plug at 145 - 155 °C, open the discharge, and the mixed rubber is obtained.

[0038] Compared with the prior art, the present invention has the following beneficial effects:

[0039] 1. The light-weight, high-strength and low-rolling-resistance tire for new energy vehicles provided by the present invention, by optimizing the tread pattern and tread rubber formula, not only realizes the light-weight of the tire, effectively reduces the rolling resistance of the tire, but also improves the strength and anti-aging performance of the tire, and extends the service life of the tire.

[0040] 2. The light-weight, high-strength and low-rolling-resistance tire for new energy vehicles provided by the present invention, by reasonably designing the transverse grooves and steel sheets in the tread pattern blocks, enhances the overall rigidity of the tire pattern and effectively reduces the rolling resistance of the tire.

[0041] 3. The light-weight, high-strength and low-rolling-resistance tire for new energy vehicles provided by the present invention, by using epoxidized solution-polymerized styrene-butadiene rubber with two different degrees of epoxidation to replace solution-polymerized styrene-butadiene rubber, helps to enhance the interaction between the rubber and fillers such as carbon black and silica, increases the dispersion of the fillers in the matrix, reduces the use of fillers, that is, still achieves excellent reinforcement effect under the premise of reducing the use of fillers, realizes light-weight while improving the strength of the tire, and effectively reduces the rolling resistance of the tire. By controlling the ratio and degree of epoxidation of the two epoxidized solution-polymerized styrene-butadiene rubbers, it also helps to improve the anti-aging performance and wet skid resistance of the tire.

[0042] 4. The light-weight, high-strength and low-rolling-resistance tire for new energy vehicles provided by the present invention, by using modified sepiolite fiber to replace silica in the tread rubber, the compatibility between the modified sepiolite fiber and the rubber matrix is improved, which can further reduce the resistance of the tire, and can reduce the usage amount of silica, reduce the tire quality, and also helps to further improve the anti-aging performance of the tire and extend the service life of the tire. Description of the Drawings

[0043] Figure 1 is a schematic diagram of the tread pattern of the light-weight, high-strength and low-rolling-resistance tire for new energy vehicles of the present invention;

[0044] In the figure, the first shoulder pattern block - 1, the first inner pattern block - 2, the central pattern block - 3, the second inner pattern block - 4, the second shoulder pattern block - 5, longitudinal groove I - 6, longitudinal groove II - 7, longitudinal groove III - 8, longitudinal groove IV - 9, the first pattern transverse groove - 11, the first steel sheet fine groove - 12, the second pattern transverse groove - 21, the second steel sheet fine groove - 22, the third pattern transverse groove - 31, the third fine groove - 32. Detailed Implementation Modes

[0045] The following non - restrictive examples can enable those of ordinary skill in the art to understand the present invention more comprehensively, but do not limit the present invention in any way. The following content is merely an exemplary illustration of the scope claimed by the present invention. Those skilled in the art can make various changes and modifications to the invention according to the disclosed content, and it should also fall within the scope claimed by the present invention.

[0046] In the present invention, the accelerator, antioxidant, and scorch retarder can be common accelerators in the art without special limitations. For example, they can be one or more of guanidine accelerators and sulfonamide accelerators; the antioxidant can be one or more of amine antioxidants, diaryl secondary amine antioxidants, or keto - amine antioxidants; the scorch retarder can be one or more of organic acid types, nitroso compounds, and sulfenamides.

[0047] In the present invention, the epoxidized solution - polymerized styrene - butadiene rubber can be directly purchased from the market or prepared from solution - polymerized styrene - butadiene rubber by existing technologies. For example, it can be prepared by epoxidizing with hydrogen peroxide and formic acid without special limitations; and the solution - polymerized styrene - butadiene rubber can be one or more of high - styrene - based solution - polymerized styrene - butadiene rubber, medium - styrene - based solution - polymerized styrene - butadiene rubber, and high - vinyl solution - polymerized styrene - butadiene rubber, also without special limitations.

[0048] The present invention will be further described below by way of specific examples. All chemical reagents used in the examples of the present invention are obtained through conventional commercial channels unless otherwise specified.

[0049] Examples 1 - 5

[0050] A lightweight, high - strength and low - rolling - resistance tire for new energy vehicles includes a tread and a sidewall; wherein,

[0051] Both the tread and the sidewall are composed of tread rubber containing the components described in Table 1 below (each component in the table is in parts by weight).

[0052] Table 1. Composition of tread rubber (parts by weight)

[0053]

[0054]

[0055] The preparation method of the above - mentioned lightweight, high - strength and low - rolling - resistance tire for new energy vehicles includes the following steps:

[0056] S1. Prepare the mixed rubber:

[0057] Preferably, the step of segmented mixing includes:

[0058] Add low-epoxy epoxidized solution-polymerized styrene-butadiene rubber, high-epoxy epoxidized solution-polymerized styrene-butadiene rubber, and natural rubber into a Banbury mixer, press the upper ram for 30 s, raise the upper ram and then press for another 10 s. At 135 °C, raise the upper ram, add carbon black and silica, and press for 15 s. Raise the upper ram and then press for another 10 s. At 150 °C, raise the upper ram, open the discharge door to obtain the first-stage masterbatch;

[0059] (2) Add zinc oxide, stearic acid, paraffin wax, and antioxidant into the Banbury mixer, press the upper ram for 25 s. At 120 °C, raise the upper ram and then press for another 18 s. Raise the upper ram and then press for another 10 s. At 145 °C, raise the upper ram, open the discharge door to obtain the second-stage masterbatch;

[0060] (3) Add sulfur, accelerator, and scorch retarder into the Banbury mixer, press the upper ram for 20 s, raise the upper ram and then press for another 15 s. Raise the upper ram and then press for another 10 s. At 145 °C, raise the upper ram, open the discharge door to obtain the mixed rubber, and let it stand at room temperature for standby;

[0061] S2. Then, make the tread and the sidewall according to the tread pattern setting to prepare a lightweight, high-strength and low-rolling-resistance tire for new energy vehicles.

[0062] The tread of the above-mentioned lightweight, high-strength and low-rolling-resistance tire for new energy vehicles adopts the pattern structure as Figure 1 shown. There are 5 tread blocks and 4 longitudinal grooves on the tread. The 5 tread blocks are the first shoulder tread block 1, the first inner tread block 2, the central tread block 3, the second inner tread block 4, and the second shoulder tread block 5 respectively; a longitudinal groove I6 is formed between the first shoulder tread block 1 and the first inner tread block 2, a longitudinal groove II7 is formed between the first inner tread block 2 and the central tread block 3, a longitudinal groove III8 is formed between the central tread block 3 and the second inner tread block 4, and a longitudinal groove IV9 is formed between the second inner tread block D and the second shoulder tread block E.

[0063] Specifically, the widths of the central tread block 3, the first inner tread block 2, and the second inner tread block 4 are 13 ± 1.5% of the contact ground width TDW, 12 ± 1.5% of TDW, and 12.5 ± 1.5% of TDW respectively; the widths of the first shoulder tread block 1 and the second shoulder tread block 5 are 20 ± 2% of TDW and 20 ± 2% of TDW respectively. Specifically, the widths of the 4 longitudinal grooves are all 5% ± 1 of TDW. By reasonably designing the widths of the tread blocks and the longitudinal grooves, the stress area of the tire can be guaranteed, the overall grounding stability of the tire tread can be ensured, and the use of rubber compound can be reduced, thereby reducing the rolling resistance.

[0064] Specifically, central steel sheet transverse grooves 31 and central steel sheets 32 are arranged at intervals and in the same inclined direction on the central tread block 3; both ends of the central steel sheet transverse groove 31 communicate with the longitudinal grooves II 7 and III 8 on both sides respectively, one end of the central steel sheet 32 communicates with the longitudinal groove II 7, and the other end extends near the tread center line; the included angle c between the arrangement direction of the central steel sheet transverse groove 31 and the tread center line is 65 ± 3°.

[0065] Specifically, first inner steel sheet transverse grooves 21, first inner steel sheets 22 and second inner steel sheets 23 are arranged at intervals and in the same inclined direction on the first inner tread block 2; both ends of the first inner steel sheet transverse groove 21 communicate with the longitudinal grooves I 6 and II 7 on both sides respectively, the outer end of the first inner steel sheet 22 communicates with the longitudinal groove I 6, and the other end extends near the center line of the first inner tread block 2, the inner end (i.e., the end close to the longitudinal groove II 7) of the second inner steel sheet 23 communicates with the longitudinal groove II 7, and the other end extends near the center line of the first inner tread block 2; the included angle b between the arrangement direction of the first inner steel sheet transverse groove 21 and the tread center line is 68 ± 5°.

[0066] Specifically, the second inner tread block 3 is arranged in a centrally symmetric manner with respect to the first inner tread block 2.

[0067] Specifically, first shoulder steel sheet transverse grooves 11 and first shoulder steel sheets 12 are arranged at intervals and in the same inclined direction on the first shoulder tread block 1; the first shoulder steel sheet transverse groove 11 penetrates through the first shoulder tread block 1, only the inner end of the first shoulder steel sheet 12 communicates with the longitudinal groove I 6, and the length of the first shoulder steel sheet 12 is less than that of the first shoulder steel sheet transverse groove 11; the included angle a between the arrangement direction of the first shoulder steel sheet transverse groove 11 and the tread center line is 85 ± 3°.

[0068] Specifically, the second shoulder tread block 5 is arranged in a centrally symmetric manner with respect to the first shoulder tread block 1.

[0069] Specifically, the tread pitch is 28 cm.

[0070] Through the multi-angle tread groove design and multi-angle steel sheet design, the space formed by the contact between the tread and the ground is reduced, the area of the grooves is increased, the rolling resistance can be effectively reduced, and the drainage capacity and grip ability are increased.

[0071] Examples 6 - 9

[0072] The difference from Example 2 is that the epoxy degrees of the low-epoxy-degree epoxidized solution-polymerized styrene-butadiene rubber and the high-epoxy-degree epoxidized solution-polymerized styrene-butadiene rubber are different, as shown in Table 2 below:

[0073] Table 2. Epoxy Degrees of Epoxidized Solution-Polymerized Styrene-Butadiene Rubber

[0074] Group Example 6 Example 7 Example 8 Example 9 High-epoxy-degree epoxidized solution-polymerized styrene-butadiene rubber 20.3％ 21.2％ 23.7％ 25.5％ Low-epoxy-degree epoxidized solution-polymerized styrene-butadiene rubber 6.1％ 6.5％ 8.4％ 8.6％

[0075] Example 10

[0076] It is different from Example 2 in that the silica white is replaced by 9 parts by weight of modified sepiolite fibers, and the modified sepiolite fibers are prepared by the following method:

[0077] The sepiolite fibers are soaked in a nitric acid solution with a mass fraction of 10%, soaked at 60 °C for 6 h. After soaking, suction filtration is carried out. After drying, they are dispersed in DMF, and bis(3-trimethoxysilylpropyl)amine (the dosage is 8.5% of the weight of the pretreated sepiolite fibers) is added, and the reaction is carried out at 70 °C for 3 h. Then suction filtration is carried out, and they are washed with absolute ethanol and deionized water and dried to obtain the modified sepiolite fibers.

[0078] Example 11

[0079] It is different from Example 10 in that bis(3-trimethoxysilylpropyl)amine is replaced by an equal amount of γ-aminopropyltrimethoxysilane.

[0080] Example 12

[0081] It is different from Example 11 in that the modified sepiolite fibers are replaced by unmodified sepiolite fibers, and the dosage remains unchanged.

[0082] Comparative Example 1

[0083] It is different from Example 2 in that the epoxidized solution-polymerized styrene-butadiene rubber is only the low-epoxy-degree epoxidized solution-polymerized styrene-butadiene rubber, and the total amount of the epoxidized solution-polymerized styrene-butadiene rubber remains unchanged.

[0084] Comparative Example 2

[0085] It is different from Example 2 in that the epoxidized solution-polymerized styrene-butadiene rubber is only the high-epoxy-degree epoxidized solution-polymerized styrene-butadiene rubber, and the total amount of the epoxidized solution-polymerized styrene-butadiene rubber remains unchanged.

[0086] Comparative Example 3

[0087] It is different from Example 2 in that the low-epoxy-degree epoxidized solution-polymerized styrene-butadiene rubber and the high-epoxy-degree epoxidized solution-polymerized styrene-butadiene rubber are replaced by an equal amount of solution-polymerized styrene-butadiene rubber.

[0088] Test Example 1

[0089] 1. Mechanical properties

[0090] The above-mentioned compounded rubbers obtained from the examples and comparative examples are vulcanized at 161 °C for 20 min, and then tested with reference to the standard GB / T528-2009. The results are shown in Table 3 below. Then, with reference to the standard GB / T3512-2014, the mechanical properties are tested after thermal oxygen aging at 100 °C for 72 h. The results are shown in Table 4 below.

[0091] 2. DMA test of tanδ-T curve scanning: The sample size is 80×10×2 mm, the vibration frequency is 10 Hz, the heating rate is 3℃ / min, the dynamic strain is 2.5%, and the scanning temperature range is -100~100℃. The results are shown in Table 5 below.

[0092] Table 3

[0093]

[0094]

[0095] As can be seen from the above table, in the tread compound of the present invention, epoxidized solution-polymerized styrene-butadiene rubber is used to replace solution-polymerized styrene-butadiene rubber, and its mechanical properties are significantly improved. Moreover, the silica in the tread compound is replaced by modified sepiolite fiber, and its mechanical properties are improved, and the dosage of modified sepiolite fiber is significantly lower than that of silica, further realizing the lightweight of the tire.

[0096] Table 4

[0097] Group Tensile strength (Mpa) Elongation at break (%) 300% modulus at specified elongation (Mpa) 100% modulus at specified elongation (Mpa) Example 1 23.10 515.84 15.23 4.93 Example 2 24.69 544.67 15.60 5.59 Example 3 23.99 523.56 15.62 5.61 Example 4 20.02 442.51 17.64 5.93 Example 5 20.84 478.52 17.23 4.98 Example 6 19.90 494.64 17.21 5.07 Example 7 23.59 529.58 15.74 5.62 Example 8 24.16 526.02 16.27 5.53 Example 9 19.86 454.11 16.23 4.38 Example 10 26.93 574.00 15.40 5.37 Example 11 25.42 524.47 16.23 5.75 Example 12 22.60 503.13 16.10 6.01 Comparative Example 1 18.29 435.65 18.09 3.90 Comparative Example 2 15.55 335.59 16.65 4.77 Comparative Example 3 16.23 366.27 17.61 3.42

[0098] As can be seen from the above table, after 72 hours of thermal-oxidative aging of the tread compound of the present invention, its tensile strength and elongation at break slightly decrease, and the 300% modulus at 100% modulus slightly increase, but the change range is small, indicating that the tread compound has excellent anti-aging performance. In addition, in the tread compound of the present invention, high-epoxy epoxidized solution-polymerized styrene-butadiene rubber and low-epoxy epoxidized solution-polymerized styrene-butadiene rubber are used to replace unepoxidized solution-polymerized styrene-butadiene rubber, which not only improves the strength but also helps to improve the anti-thermal-oxidative aging performance.

[0099] Table 5

[0100] Group tanδ@60°C tanδ@0°C Example 1 0.070 0.581 Example 2 0.063 0.610 Example 3 0.068 0.602 Example 4 0.087 0.471 Example 5 0.096 0.455 Example 6 0.094 0.463 Example 7 0.063 0.567 Example 8 0.069 0.575 Example 9 0.102 0.511 Example 10 0.051 0.688 Example 11 0.067 0.617 Example 12 0.109 0.501 Comparative Example 1 0.117 0.458 Comparative Example 2 0.128 0.419 Comparative Example 3 0.136 0.446

[0101] The tire specifications obtained in the above examples and comparative examples are all 225 / 55R17 97W. As shown in the table, compared with Comparative Examples 1-3, the tanδ@60℃ of the tires obtained in the examples is significantly reduced, that is, the rolling resistance is decreased. It can be seen that adding two kinds of solution-polymerized styrene-butadiene rubbers with different epoxy degrees to the tread compound of the present invention helps to reduce the rolling resistance of the tire. It can also be seen that the tanδ@60℃ of the tires obtained in the examples is higher than that of the comparative examples, indicating that replacing solution-polymerized styrene-butadiene rubber with two kinds of epoxidized solution-polymerized styrene-butadiene rubbers with different epoxy degrees in the tread compound can not only reduce the rolling resistance but also help to improve the wet skid resistance of the tire.

[0102] The above description of the embodiments is provided to enable those of ordinary skill in the art to understand and use the invention. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative efforts. Therefore, the present invention is not limited to the above embodiments, and all improvements and modifications made by those skilled in the art without departing from the scope of the present invention according to the disclosure of the present invention should be within the protection scope of the present invention.

Claims

1. A lightweight, high-strength and low rolling resistance tire for new energy vehicles, characterized in that: The invention comprises a tread and a sidewall; wherein the tread and the sidewall are both composed of a tread rubber comprising the following components: 70-80 parts of low-epoxy epoxidized solution-polymerized styrene-butadiene rubber and high-epoxy epoxidized solution-polymerized styrene-butadiene rubber, 20-30 parts of natural rubber, 25-40 parts of carbon black, 1-10 parts of aromatic oil, 0.5-6 parts of stearic acid, 0.5-8 parts of zinc oxide, 0.2-6 parts of sulfur, 0.3-5 parts of accelerator, 0.5-8 parts of antioxidant, 0.5-6 parts of scorch retarder, and 15-25 parts of white carbon black or modified sepiolite fiber, wherein the modified sepiolite fiber is added in an amount of 5-9% of the total weight of the rubber component; The epoxy degree of low-epoxy epoxidized solution-polymerized styrene-butadiene rubber is 6.5-8.4%, and the epoxy degree of high-epoxy epoxidized solution-polymerized styrene-butadiene rubber is 21.2-23.7%. The mass ratio of the low-epoxidation-degree epoxidized solution-polymerized styrene-butadiene rubber to the high-epoxidation-degree epoxidized solution-polymerized styrene-butadiene rubber is (50-70):(10-20); The modified sepiolite fiber is specifically prepared by the following method: The sepiolite fiber is soaked in acid solution at 60-70°C for 6-8 hours. After soaking, it is filtered, dried and dispersed in DMF. A secondary amino silane coupling agent is added, and the reaction is carried out at 70-80°C for 2-3 hours. The fiber is filtered, washed with anhydrous ethanol and deionized water, and dried to obtain the modified sepiolite fiber.

2. A lightweight, high-strength and low rolling resistance tire for new energy vehicles according to claim 1, characterized in that: The mass ratio of the low-epoxidation-degree epoxidized solution-polymerized styrene-butadiene rubber to the high-epoxidation-degree epoxidized solution-polymerized styrene-butadiene rubber is 60:

18.

3. A lightweight, high-strength and low rolling resistance tire for new energy vehicles according to claim 1 or 2, characterized in that: The tread is provided with 5 pattern blocks and 4 longitudinal grooves; the 5 pattern blocks are respectively a first shoulder pattern block, a first inner pattern block, a central pattern block, a second inner pattern block, and a second shoulder pattern block; a longitudinal groove I is formed between the first shoulder pattern block and the first inner pattern block, a longitudinal groove II is formed between the first inner pattern block and the central pattern block, a longitudinal groove III is formed between the central pattern block and the second inner pattern block, and a longitudinal groove IV is formed between the second inner pattern block and the second shoulder pattern block.

4. A lightweight, high-strength and low rolling resistance tire for new energy vehicles according to claim 3, characterized in that: The widths of the central pattern block, the first inner pattern block and the second inner pattern block are 13±1.5%, 12±1.5% and 12.5±1.5% of the ground contact surface width TDW respectively; the widths of the first shoulder pattern block and the second shoulder pattern block are 20±2% and 20±2% of TDW respectively.

5. A lightweight, high-strength and low rolling resistance tire for new energy vehicles according to claim 3, characterized in that: The central pattern block is provided with central steel sheet transverse grooves and central steel sheets arranged at intervals and having the same inclination direction; The first inner steel sheet transverse grooves, the first inner steel sheet and the second inner steel sheet are arranged at intervals and have the same inclination direction on the first inner pattern block; The first shoulder pattern block is provided with first shoulder steel sheet transverse grooves and first shoulder steel sheets which are arranged at intervals and have the same inclination direction.

6. A lightweight, high-strength and low rolling resistance tire for new energy vehicles according to claim 5, characterized in that: The second inner pattern block is arranged in a centrally symmetrical manner with the first inner pattern block; and the second shoulder pattern block is arranged in a centrally symmetrical manner with the first shoulder pattern block.

7. A method for preparing a lightweight, high-strength and low rolling resistance tire for new energy vehicles according to any one of claims 1 to 6, characterized in that: The following steps are involved: The tread rubber is mixed to obtain a mixed rubber, and then the tread and sidewall are made according to the tread pattern setting to prepare a lightweight, high-strength and low rolling resistance tire for new energy vehicles.

8. The preparation method according to claim 7, characterized in that: The preparation steps of the rubber compound include: (1) adding low-epoxidation epoxidized solution-polymerized styrene-butadiene rubber, high-epoxidation epoxidized solution-polymerized styrene-butadiene rubber, and natural rubber into an internal mixer, and mixing at 135-160° C. to obtain a masterbatch; (2) adding zinc oxide, stearic acid, paraffin wax, and antioxidant, and kneading at 120-155° C. to obtain a second-stage masterbatch; (3) Add the second-stage masterbatch, sulfur, accelerator and scorch retarder, and mix at 140-150°C to obtain the mixed rubber.

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