Sidewall rubber with four-composite rubber material structure

Abstract

The invention relates to the technical field of tire manufacturing, and discloses a sidewall rubber with a four-compound rubber structure, the sidewall rubber comprises a sidewall pad rubber, a sidewall main rubber, a sidewall outer protective rubber and a sidewall reinforcing rubber, the sidewall pad rubber is located above the sidewall main rubber and is connected with a tire shoulder, the sidewall outer protective rubber is located below the sidewall main rubber, and the sidewall reinforcing rubber is connected with the sidewall pad rubber. And the sidewall reinforcing rubber is positioned on the inner side of the sidewall outer protective rubber. The invention provides the sidewall rubber with a four-composite rubber material structure, breaks through the traditional sidewall rubber with a two-composite rubber material structure, reduces the heat generation and deformation of the tire shoulder part, effectively reduces the deformation of the bead seam allowance part, enables the deformation of the tire to be concentrated at the middle tire sidewall part, and improves the safety of the tire. Therefore, stress deformation and energy loss of the tire during running are reduced, and rolling resistance is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of tire manufacturing, and more specifically, to a sidewall-type rubber compound with a four-composite rubber structure. Background Art

[0002] As the only component in direct contact with the ground, the structure and mechanical properties of tires directly affect many performance aspects of automobiles, such as handling stability, riding comfort, and fuel economy. Rolling resistance is the resistance generated when a tire contacts the road surface during vehicle driving, and it is one of the main components of vehicle driving resistance. Reducing the rolling resistance of tires is an important way to improve vehicle fuel efficiency and reduce emissions. To improve the average utilization rate and efficiency of tires, Japan, the European Union, and the United States have successively introduced relevant regulations, requiring tire manufacturers to provide information such as rolling resistance. Tires sold in Europe must meet the ECER117 regulation. The new ECE R117 regulation has tightened the indicators for rolling resistance and wet grip. The rolling resistance requirement must be based on the specification with the minimum load index as the worst specification for standard tires for certification. In this regulation adjustment, the performance indicators have been tightened significantly, and it is difficult to improve. The new regulation requires that for tire specifications with a load index less than 87, the rolling resistance coefficient should not be greater than 10.

[0003] As is well known, the rolling resistance of tires is closely related to patterns, profiles, materials, structures, road surfaces, driving conditions, etc. Among them, driving conditions and road surfaces are uncontrollable factors, and patterns, profiles, structures, and materials are the main entry points for reducing rolling resistance. Currently, for a series of 155 / 65R13 73T tires with a certain pattern in the applicant's production, the rolling resistance value > 10. If the rolling resistance coefficient is to be reduced below 10, on the premise of saving costs without reprocessing the mold, the applicant makes adjustments in terms of structure and materials to reduce the rolling resistance, so as to meet the requirements of the new ECE R117 regulation.

[0004] The calculation of rolling resistance usually involves the rolling resistance coefficient (Cr or RR), which is a parameter to measure the friction force between the tire and the road surface and determines the magnitude of the rolling resistance.

[0005] The tire rolling resistance Fr is the energy loss or energy consumption per unit driving distance, Fr = Cr × W, where Fr is the rolling resistance, W is the tire test load (or the weight of the vehicle), and Cr is the rolling resistance coefficient. The smaller Cr is, the better the fuel economy of the vehicle.

[0006] The rolling resistance coefficient RR can be defined and expressed as: RR = Σεσε • tanδ • dV, where RR is the rolling resistance coefficient, Σεσε is the total strain energy, dV is the volume of each tire component, and tanδ(60°C) is the loss of the rubber compound. The three parameters affecting rolling resistance are: namely, strain energy, volume, and tanδ. The rolling resistance coefficient decreases as these three values decrease, but it is difficult to decrease these three values simultaneously.

[0007] The energy loss caused by the cyclic deformation of tire materials is the main reason for the rolling energy consumption of tires, accounting for about 80% - 95% of the rolling energy consumption of tires. The cyclic contact deformation between the tire and the road is mainly divided into compression, shear and bending deformations. The rolling resistance of tires is mainly caused by the energy loss of the rubber material and reinforcing material inside the tire due to periodic deformation. To reduce the rolling resistance of tires, the most important method is to reduce tire deformation and energy loss. The tire as a whole can be divided into the tread part, the sidewall part and the bead part. When the tire rolls, three main deformations occur, namely the bending of the tread, sidewall and bead regions, and the sidewall part is the part with the largest tire deformation. Therefore, it is necessary to reduce the sidewall strain near the tread region and the bead region, so that the strain is mainly concentrated in the middle region of the sidewall part, making the distribution of energy loss more uniform.

[0008] Chinese invention patent (Publication No.: CN114874510A, Publication Date: August 9, 2022) discloses a tread-type rubber with a five-composite rubber structure. The tread-type rubber includes an upper tread rubber, a lower tread rubber, a base rubber, a shoulder rubber and a conductive rubber. The upper tread rubber, the lower tread rubber and the base rubber are sequentially arranged from outside to inside to form a tread layer. The upper tread rubber adopts a low rolling resistance and low heat generation rubber composition, and the lower tread rubber adopts a low rolling resistance, good handling, low wear and tear resistance and tear resistance rubber composition; the shoulder rubber is arranged on the transverse sides of the tread layer, and the conductive rubber is located on one side of the center of the tread layer. The conductive rubber penetrates the upper tread rubber, the lower tread rubber and the base rubber from outside to inside. This tread-type rubber controls the rolling resistance and handling through two different combinations of upper and lower tread rubbers. After vulcanization, it can provide a tire with low rolling resistance, high wet grip and good handling performance.

[0009] Chinese invention patent (Publication No.: CN118769767A, Publication Date: October 15, 2024) discloses a tread-type rubber with a five-composite tread different-rubber structure and its tire. The tread-type rubber includes a tread rubber, a base rubber, a conductive rubber and a shoulder rubber. The tread rubber and the base rubber are sequentially arranged from outside to inside to form a tread layer. The tread rubber includes a middle tread rubber and a shoulder tread rubber. The shoulder tread rubber is arranged on the transverse sides of the middle tread rubber. The middle tread rubber adopts a low rolling resistance rubber composition. The shoulder rubber is arranged on the transverse sides of the tread layer, and the conductive rubber is located at the center of the tread layer. The conductive rubber penetrates the middle tread rubber and the base rubber from outside to inside. By controlling the rolling resistance, wear resistance, braking and handling through two different combinations of inner and outer tread rubbers, after vulcanization, it can provide a tire with low rolling resistance, high wear resistance, good braking performance and good handling performance, which can effectively reduce the hysteresis loss of the tire shoulder while taking into account the wet grip performance of the tire. Summary of the Invention

[0010] In view of the deficiencies of the prior art, the present invention provides a sidewall-type rubber with a four-composite rubber structure.

[0011] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions: A sidewall rubber with a four-composite rubber structure, the sidewall rubber comprising a sidewall cushion rubber (1), a sidewall main rubber (2), a sidewall outer rubber (3) and a sidewall reinforcing rubber (4), the sidewall cushion rubber (1) being located above the sidewall main rubber (2) and supporting the tire shoulder, the sidewall outer rubber (3) being located below the sidewall main rubber (2), and the sidewall reinforcing rubber (4) being located on the inner side of the sidewall outer rubber (3); The sidewall rubber (1) is a rubber composition with low heat generation, high modulus and high hardness, with a Shore hardness of 64-68 and a composite modulus E * The main rubber (2) of the sidewall adopts a low modulus rubber composition with a Shore hardness of 54-58 and a composite modulus E * The sidewall outer rubber (3) adopts a high modulus rubber composition C, with a Shore hardness of 68-72 and a composite modulus E * is 16.0-20.0mPa, tanδ is 0.14-0.18; the sidewall reinforcing rubber (4) adopts a high modulus rubber composition, Shore hardness is 80-90, and the composite modulus E * ≥20.0mPa, tanδ is 0.10-0.16; The sidewall cushion rubber (1) is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber: 60-90 parts of natural rubber, 10-40 parts of butadiene rubber, 10-30 parts of white carbon black, 25-45 parts of low heat build-up carbon black, 2-3.5 parts of silane coupling agent TESPT, 1.0-3.0 parts of adhesive resin, 0.5-1.5 parts of adhesion promoter HMT, and 1-3 parts of antioxidant; The sidewall main rubber (2) is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber: 30-50 parts of natural rubber, 50-70 parts of butadiene rubber, 25-45 parts of carbon black, 3-10 parts of environmentally friendly oil, 2-5 parts of p-phenylenediamine antioxidant, 2-4 parts of quinoline antioxidant, and 1-2.5 parts of microcrystalline wax; The sidewall outer rubber (3) is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber: 30-60 parts of natural rubber, 30-50 parts of butadiene rubber, 10-25 parts of styrene-butadiene rubber, 65-80 parts of carbon black, 3-8 parts of environmentally friendly oil, 1-3 parts of p-phenylenediamine antioxidant, 1-2 parts of quinoline antioxidant, 1-2 parts of microcrystalline wax, 2-4 parts of leveling agent, and 2-4 parts of tackifying resin; The sidewall reinforcing rubber (4) is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber: 70-90 parts of natural rubber, 10-30 parts of high-cis polybutadiene rubber, 5-10 parts of liquid reclaimed rubber, 50-70 parts of carbon black, 8-20 parts of reinforcing resin, 1-5 parts of methyl donor. The methyl donor forms a resin network during vulcanization with the reinforcing resin, and 1-3 parts of p-phenylenediamine antioxidant.

[0012] Preferably, the sidewall cushion rubber (1) is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber: 70-80 parts of natural rubber, 20-30 parts of polybutadiene rubber, 15-25 parts of white carbon black, 30-40 parts of low heat build-up carbon black, 2-3.5 parts of silane coupling agent TESPT, 1.0-3.0 parts of bonding resin, 0.5-1.5 parts of bonding accelerator HMT, 1-3 parts of antioxidant, 2-4 parts of zinc oxide, 1-2 parts of stearic acid, 2.0-5.0 parts of vulcanizing agent, 0.5-1.5 parts of accelerator; The sidewall main rubber (2) is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber: 35-45 parts of natural rubber, 55-65 parts of polybutadiene rubber, 30-40 parts of carbon black, 6-8 parts of environmental protection oil, 2-5 parts of p-phenylenediamine antioxidant, 2-4 parts of quinoline antioxidant, 1-2.5 parts of microcrystalline wax, 2-4 parts of zinc oxide, 1-2 parts of stearic acid, 1-3 parts of vulcanizing agent, 0.5-1.5 parts of accelerator; The sidewall outer protection rubber (3) is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber: 40-50 parts of natural rubber, 35-45 parts of polybutadiene rubber, 15-20 parts of styrene-butadiene rubber, 70-80 parts of carbon black, 3-8 parts of environmental protection oil, 1-3 parts of p-phenylenediamine antioxidant, 1-2 parts of quinoline antioxidant, 1-2 parts of microcrystalline wax, 2-4 parts of homogenizer, 2-4 parts of tackifying resin, 2-4 parts of zinc oxide, 1-2 parts of stearic acid, 1-3 parts of vulcanizing agent, 1-3 parts of accelerator; The sidewall reinforcing rubber (4) is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber: 75-85 parts of natural rubber, 15-25 parts of high-cis polybutadiene rubber, 5-10 parts of liquid reclaimed rubber, 55-65 parts of carbon black, 12-16 parts of reinforcing resin, 1-5 parts of methyl donor, 1-3 parts of p-phenylenediamine antioxidant, 2-4 parts of zinc oxide, 1-2 parts of stearic acid, 1-3 parts of vulcanizing agent, 1-3 parts of accelerator.

[0013] Preferably, in the sidewall cushion rubber (1), the polybutadiene rubber is high-cis polybutadiene rubber; The white carbon black is high-dispersion white carbon black, and the BET specific surface area is 150-170m 2 / g; The low heat - generating carbon black is a low - structure or relatively large - particle - size carbon black, including but not limited to N660, N326, N550, N375.

[0014] Preferably, in the main rubber of the tire side (2), the cis - 1,4 - polybutadiene rubber is preferably neodymium - based high - cis cis - 1,4 - polybutadiene rubber; The BET specific surface area of the carbon black is 34 - 46 m 2 / g, and the particle size is 40 - 48 nm; Preferably, in the outer protective rubber of the tire side (3), the cis - 1,4 - polybutadiene rubber is high - cis cis - 1,4 - polybutadiene rubber The BET specific surface area of the carbon black is 71 - 85 m 2 / g, and the particle size is 26 - 30 nm; The homogenizer is a mixture of different - polarity resins and asphaltenes, and the typical grade is 40MSF.

[0015] Preferably, in the reinforcing rubber of the tire side (4), the high - cis cis - 1,4 - polybutadiene rubber is neodymium - based high - cis cis - 1,4 - polybutadiene rubber; The liquid reclaim rubber is tread reclaim rubber, and the mesh number of the rubber powder before the reclaim rubber is cracked is greater than 40 meshes to achieve good reinforcing and processing effects; The BET specific surface area of the carbon black is 34 - 46 m 2 / g, and the particle size is 40 - 48 nm; The methyl donor is hexamethylenetetramine, and its English name is accelerator HMT.

[0016] Preferably, the lower width of the cushion rubber of the tire side (1) is 17±3 mm, and the upper width is 25±3 mm.

[0017] Preferably, the width of the reinforcing rubber of the tire side (4) is 15 mm - 20 mm smaller than the lower width of the outer protective rubber of the tire side (3).

[0018] Preferably, the central thickness ratio of the outer protective rubber of the tire side (3) and the reinforcing rubber of the tire side (4) is (2 - 4):1.

[0019] Furthermore, the present invention also provides a tire, which includes a tread part, a tire - side part, a belt layer part, and a bead part. The tire - side part is prepared by vulcanizing the above - mentioned tire - side rubber compound.

[0020] The beneficial effects of the present invention are as follows: The present invention provides a tire - side rubber compound with a four - composite rubber - compound structure, breaking through the traditional two - composite rubber - compound structure of the tire - side rubber compound, reducing the heat generation and deformation at the shoulder part of the tire, and effectively reducing the deformation at the bead part of the tire, making the deformation of the tire concentrated in the middle tire - side part. In this way, the stress deformation and energy loss during the tire's driving are reduced, thereby reducing the rolling resistance. Description of the Drawings

[0021] Figure 1It is a cross-sectional view of the tire of the present invention.

[0022] Figure 2 The figure is a structural diagram of the sidewall rubber of the four-composite rubber structure of the present invention.

[0023] Figure 3 This is a cross-sectional view of a traditional tire.

[0024] Figure 4 This is a diagram showing the structure of the sidewall rubber of a traditional tire.

[0025] Figure 5 The following is a comparison chart of the rolling resistance of the sidewall rubber of the four-composite rubber structure and the sidewall rubber of the traditional tire.

[0026] Figure 6 Schematic diagram of the tread patterns of the tires of Example 2 and Comparative Example 1.

[0027] Figure numerals: 1-sidewall cushion rubber, 2-sidewall main rubber, 3-base rubber, 4-sidewall reinforcing rubber, 5-bead, 6-tread, 7-shoulder, 8-apex rubber. DETAILED DESCRIPTION

[0028] 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.

[0029] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0030] In a first aspect, the present invention provides a sidewall rubber having a four-composite rubber structure, such as Figure 1 , 2 The sidewall rubber comprises a sidewall cushion rubber 1, a sidewall main rubber 2, a sidewall outer rubber 3 and a sidewall reinforcing rubber 4. The sidewall cushion rubber 1 is located above the sidewall main rubber 2 and supports the tire shoulder. The sidewall outer rubber 3 is located below the sidewall main rubber 2. The sidewall reinforcing rubber 4 is located on the inner side of the sidewall outer rubber 3.

[0031] When the tire uses two composite sidewall rubbers (such as Figure 3 , 4As shown in the figure, there are three parts that will deform, namely the shoulder 5, the middle sidewall, and the bead 7, which will cause a large deformation of the tire.

[0032] When the tire adopts the structure design of four-composite sidewall rubber (such as Figure 1 , 2 As shown, the heat generation and deformation of the tire shoulder 5 are reduced, and the deformation of the tire bead 7 is also effectively reduced, so that the deformation of the tire is concentrated in the middle sidewall area, reducing the stress deformation and energy loss of the tire during driving, thereby reducing the rolling resistance.

[0033] The sidewall rubber 1 is located above the sidewall main rubber 2 and supports the tire shoulder. The tire shoulder is where the endpoints of various tire components are concentrated and is also the area with greater deformation. When the tire is rotating, the shear heat generated by the shoulder after being stressed is small, thereby improving the tire rolling resistance. Therefore, the sidewall rubber 1 uses a rubber composition with low heat generation, high modulus, and high hardness. The Shore hardness is 64-68, and the composite modulus E * It is 12.0-16.0mPa, and tanδ is 0.07-0.10.

[0034] The Shore hardness of the sidewall cushion rubber 1 is 64-68, for example, 64, 65, 66, 67, 68, etc., preferably 65-67.

[0035] In the sidewall rubber 1, the composite modulus E * It is 12.0-16.0 mPa, for example, it can be 12.0 mPa, 13.0 mPa, 14.0 mPa, 15.0 mPa, 16.0 mPa, etc., preferably 13.0-15.0 mPa.

[0036] The sidewall cushion rubber 1tanδ is 0.07-0.10, for example, it can be 0.07, 0.07, 0.08, 0.09, 0.10, etc., preferably 0.09-0.10.

[0037] The sidewall rubber 2 is the part of the tire that is most prone to deformation. It can protect the carcass cord from damage and should have excellent flex resistance. Figure 3 , 4 The sidewall main rubber 2 has some functions in the traditional structure, so it is possible to further consider reducing the rolling resistance. Therefore, the sidewall main rubber 2 adopts a low modulus rubber composition with a Shore hardness of 54-58 and a composite modulus E * It is 5.0-9.0mPa, and tanδ is 0.08-0.12.

[0038] The Shore hardness of the sidewall main rubber 2 is 54-58, for example, it can be 54, 55, 56, 57, 58, etc., preferably 55-57.

[0039] In the main sidewall rubber 2, the complex modulus E * is 5.0 - 9.0 mPa, and can be, for example, 5.0 mPa, 13.0 mPa, 6.0 mPa, 7.0 mPa, 8.0 mPa, 9.0 mPa, etc., preferably 6.0 - 8.0 mPa.

[0040] In the main sidewall rubber 2, tanδ is 0.08 - 0.12, and can be, for example, 0.08, 0.09, 0.10, 0.11, 0.12, etc., preferably 0.08 - 0.10.

[0041] The outer sidewall protection rubber 3 is in direct contact with the rim to support the structure of the tire, so it requires relatively high rigidity, hardness and wear resistance. Therefore, the outer sidewall protection rubber 3 uses a high - modulus rubber composition C, with a Shore hardness of 68 - 72, and the complex modulus E * is 16.0 - 20.0 mPa, and tanδ is 0.14 - 0.18.

[0042] For the outer sidewall protection rubber 3 mentioned above, the Shore hardness is 68 - 72, and can be, for example, 68, 69, 70, 71, 72, etc., preferably 69 - 71.

[0043] For the outer sidewall protection rubber 3, the complex modulus E * is 16.0 - 20.0 mPa, and can be, for example, 16.0 mPa, 17.0 mPa, 18.0 mPa, 19.0 mPa, 20.0 mPa, etc., preferably 17.0 - 19.0 mPa.

[0044] For the outer sidewall protection rubber 3, tanδ is 0.14 - 0.18, and can be, for example, 0.14, 0.15, 0.16, 0.17, 0.18, etc., preferably 0.16 - 0.18.

[0045] The sidewall reinforcing rubber 4 is located between the apex rubber and the outer sidewall protection rubber 3. The purpose is to further enhance the modulus in the bead area, improve the rigidity of the bead part, and disperse the stress in the bead part outside the apex rubber. Thus, when the tire is under load during driving, the high modulus in the bead part reduces the deformation of this part, thereby reducing heat generation, that is, reducing the energy loss during tire driving, and further improving the rolling resistance performance of the tire. Therefore, the sidewall reinforcing rubber 4 uses a high - modulus rubber composition, with a Shore hardness of 80 - 90, and the complex modulus E * ≥20.0 mPa, and tanδ is 0.10 - 0.16.

[0046] For the sidewall reinforcing rubber 4 mentioned above, the Shore hardness is 80 - 90, and can be, for example, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, etc., preferably 84 - 86.

[0047] The sidewall reinforcing rubber 4, complex modulus E * ≥20.0 mPa, for example, it can be 20.0 mPa, 21.0 mPa, 22.0 mPa, 23.0 mPa, 24.0 mPa, etc. Preferably, the complex modulus E * ≥22.0 mPa.

[0048] For the sidewall reinforcing rubber 4, tanδ is 0.10 - 0.16, for example, it can be 0.10, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, etc. Preferably, it is 0.14 - 0.16.

[0049] For the sidewall rubber of the four - composite rubber structure mentioned above, it needs to be matched with corresponding rubber materials. The rubber material formulations for each part are as follows.

[0050] The sidewall cushion rubber 1 is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber: 60 - 90 parts of natural rubber, 10 - 40 parts of cis - 1,4 - polybutadiene rubber, 10 - 30 parts of silica, 25 - 45 parts of low - heat - generating carbon black, 2 - 3.5 parts of silane coupling agent TESPT, 1.0 - 3.0 parts of adhesive resin, 0.5 - 1.5 parts of adhesive accelerator HMT, and 1 - 3 parts of antioxidant.

[0051] The sidewall main rubber 2 is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber: 30 - 50 parts of natural rubber, 50 - 70 parts of cis - 1,4 - polybutadiene rubber, 25 - 45 parts of carbon black, 3 - 10 parts of environmental - friendly oil, 2 - 5 parts of p - phenylenediamine antioxidant, 2 - 4 parts of quinoline antioxidant, and 1 - 2.5 parts of microcrystalline wax.

[0052] The sidewall outer protection rubber 3 is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber: 30 - 60 parts of natural rubber, 30 - 50 parts of cis - 1,4 - polybutadiene rubber, 10 - 25 parts of styrene - butadiene rubber, 65 - 80 parts of carbon black, 3 - 8 parts of environmental - friendly oil, 1 - 3 parts of p - phenylenediamine antioxidant, 1 - 2 parts of quinoline antioxidant, 1 - 2 parts of microcrystalline wax, 2 - 4 parts of homogenizer, and 2 - 4 parts of tackifying resin.

[0053] The sidewall reinforcing rubber 4 is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber: 70 - 90 parts of natural rubber, 10 - 30 parts of high - cis - 1,4 - polybutadiene rubber, 5 - 10 parts of liquid reclaimed rubber, 50 - 70 parts of carbon black, 8 - 20 parts of reinforcing resin, 1 - 5 parts of methyl donor. The methyl donor and the reinforcing resin form a resin network during vulcanization, and 1 - 3 parts of p - phenylenediamine antioxidant.

[0054] As a preferred embodiment of the present invention, the sidewall cushion gum 1 is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber: 70-80 parts of natural rubber, 20-30 parts of cis-1,4-polybutadiene rubber, 15-25 parts of white carbon black, 30-40 parts of low heat build-up carbon black, 2-3.5 parts of silane coupling agent TESPT, 1.0-3.0 parts of adhesive resin, 0.5-1.5 parts of adhesive accelerator HMT, 1-3 parts of antioxidant, 2-4 parts of zinc oxide, 1-2 parts of stearic acid, 2.0-5.0 parts of vulcanizing agent, and 0.5-1.5 parts of accelerator.

[0055] As a preferred embodiment of the present invention, the sidewall main gum 2 is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber: 35-45 parts of natural rubber, 55-65 parts of cis-1,4-polybutadiene rubber, 30-40 parts of carbon black, 6-8 parts of environmental protection oil, 2-5 parts of p-phenylenediamine antioxidant, 2-4 parts of quinoline antioxidant, 1-2.5 parts of microcrystalline wax, 2-4 parts of zinc oxide, 1-2 parts of stearic acid, 1-3 parts of vulcanizing agent, and 0.5-1.5 parts of accelerator.

[0056] As a preferred embodiment of the present invention, the sidewall outer protective gum 3 is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber: 40-50 parts of natural rubber, 35-45 parts of cis-1,4-polybutadiene rubber, 15-20 parts of styrene-butadiene rubber, 70-80 parts of carbon black, 3-8 parts of environmental protection oil, 1-3 parts of p-phenylenediamine antioxidant, 1-2 parts of quinoline antioxidant, 1-2 parts of microcrystalline wax, 2-4 parts of homogenizer, 2-4 parts of tackifying resin, 2-4 parts of zinc oxide, 1-2 parts of stearic acid, 1-3 parts of vulcanizing agent, and 1-3 parts of accelerator.

[0057] As a preferred embodiment of the present invention, the sidewall reinforcing gum 4 is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber: 75-85 parts of natural rubber, 15-25 parts of high-cis cis-1,4-polybutadiene rubber, 5-10 parts of liquid reclaimed rubber, 55-65 parts of carbon black, 12-16 parts of reinforcing resin, 1-5 parts of methyl donor, 1-3 parts of p-phenylenediamine antioxidant, 2-4 parts of zinc oxide, 1-2 parts of stearic acid, 1-3 parts of vulcanizing agent, and 1-3 parts of accelerator.

[0058] As an alternative embodiment of the present invention, in the sidewall cushion gum 1, the cis-1,4-polybutadiene rubber is high-cis cis-1,4-polybutadiene rubber; the white carbon black is high-dispersion white carbon black with a BET specific surface area of 150-170 m 2 / g, for example, it can be 150 m 2 / g, 160 m 2 / g or 170 m 2 / g; the low heat build-up carbon black includes but is not limited to N660, N326, N550, N375.

[0059] As an alternative embodiment of the present invention, in the sidewall main rubber 2, the cis-1,4-polybutadiene rubber is preferably neodymium-based high-cis cis-1,4-polybutadiene rubber; The BET specific surface area of the carbon black is 34 - 46 m 2 / g, and for example, it can be 34 m 2 / g, 36 m 2 / g, 38 m 2 / g, 40 m 2 / g, 42 m 2 / g, 44 m 2 / g, 46 m 2 / g; the particle size of the carbon black is 40 - 48 nm, and for example, it can be 40 nm, 41 nm, 42 nm, 43 nm, 44 nm, 45 nm, 46 nm, 47 nm, 48 nm.

[0060] As an alternative embodiment of the present invention, in the sidewall outer protection rubber 3, the cis-1,4-polybutadiene rubber is high-cis cis-1,4-polybutadiene rubber; The BET specific surface area of the carbon black is 71 - 85 m 2 / g, and for example, it can be 71 m 2 / g, 73 m 2 / g, 75 m 2 / g, 77 m 2 / g, 79 m 2 / g, 81 m 2 / g, 83 m 2 / g, 85 m 2 / g; the particle size of the carbon black is 26 - 30 nm, and for example, it can be 26 nm, 27 nm, 28 nm, 29 nm, 30 nm; The homogenizer is a mixture of different polar resins and asphaltenes.

[0061] As an alternative embodiment of the present invention, in the sidewall reinforcing rubber 4, the high-cis cis-1,4-polybutadiene rubber is neodymium-based high-cis cis-1,4-polybutadiene rubber; The liquid reclaimed rubber is tread reclaimed rubber, and the mesh number of the rubber powder before the cracking of the reclaimed rubber is greater than 40 mesh; The BET specific surface area of the carbon black is 34 - 46 m 2 / g, 34 m 2 / g, 36 m 2 / g, 38 m 2 / g, 40 m 2 / g, 42 m 2 / g, 44 m 2 / g, 46 m 2 / g; the carbon black has a particle size of 40 - 48 nm, for example, it can be 40 nm, 41 nm, 42 nm, 43 nm, 44 nm, 45 nm, 46 nm, 47 nm, 48 nm; The methyl donor is hexamethylenetetramine.

[0062] As an optional embodiment of the present invention, the lower width of the sidewall cushion gum 1 is 17 ± 3 mm, and the upper width is 25 ± 3 mm; Among them, the lower width of the sidewall cushion gum 1 can be 14 mm, 15 mm, 16 mm, 17 mm, 18 mm, 19 mm, 20 mm; Among them, the upper width of the sidewall cushion gum 1 can be 22 mm, 23 mm, 24 mm, 25 mm, 26 mm, 27 mm, 28 mm.

[0063] It should be noted that the position for measuring the lower width of the sidewall cushion gum 1 is on the side away from the tread 6. In Figure 2 the length of the bottom line segment of the shown sidewall cushion gum 1 represents the lower width of the sidewall cushion gum 1, and the length of the line segment above the sidewall cushion gum 1 represents the upper width of the sidewall cushion gum 1.

[0064] As an optional embodiment of the present invention, the width of the sidewall reinforcing gum 4 is 15 mm - 20 mm smaller than the lower width of the sidewall outer protection gum 3, for example, it can be 15 mm, 16 mm, 17 mm, 18 mm, 19 mm, 20 mm.

[0065] It should be noted that the positions for measuring the width of the sidewall reinforcing gum 4 and the lower width of the sidewall outer protection gum 3 are both on the side away from the tread 6. In Figure 2 the length of the bottom line segment of the shown sidewall reinforcing gum 4 represents the width of the sidewall reinforcing gum 4, and the length of the bottom line segment of the sidewall outer protection gum 3 represents the lower width of the sidewall outer protection gum 3.

[0066] As an optional embodiment of the present invention, the ratio of the center thickness of the sidewall outer protection gum 3 to the center thickness of the sidewall reinforcing gum 4 is (2 - 4):1, that is, the ratio of the maximum thickness of the sidewall outer protection gum 3 to the maximum thickness of the sidewall reinforcing gum 4 can be 2:1, 3:1, 4:1.

[0067] As an optional embodiment of the present invention, the cis - content in the high - cis polybutadiene rubber used for the sidewall reinforcing gum 4 is ≥96%; the liquid reclaim rubber includes but is not limited to tire reclaim rubber, butyl reclaim rubber, latex reclaim rubber, chlorinated butyl reclaim rubber.

[0068] In the second aspect, the present invention provides a tire, which includes a tread part, a sidewall part, a belt layer part and a bead part, and the sidewall part is prepared by vulcanizing the sidewall - type rubber described above.

[0069] The technical solution of the present invention will be further described below in conjunction with embodiments.

[0070] Example 1 A sidewall rubber with a four-composite rubber structure, such as Figure 1 , 2 The sidewall rubber comprises a sidewall cushion rubber 1, a sidewall main rubber 2, a sidewall outer rubber 3 and a sidewall reinforcing rubber 4; the sidewall cushion rubber 1 is located above the sidewall main rubber 2 and supports the tire shoulder; the sidewall outer rubber 3 is located below the sidewall main rubber 2, the sidewall outer rubber 3 is partially overlapped on the inner side of the sidewall main rubber 2, and the bottom inner interface is in contact with the tire bead 5; the sidewall reinforcing rubber 4 is located on the inner side of the sidewall outer rubber 3 and is completely wrapped between the apex rubber 8 and the sidewall outer rubber 3.

[0071] The sidewall cushion rubber 1 is prepared by mixing the raw materials including the following components based on 100 parts by weight of raw rubber: 75 parts of natural rubber, 25 parts of butadiene rubber, 20 parts of white carbon black, 35 parts of low heat build-up carbon black, 3.0 parts of silane coupling agent TESPT, 2.0 parts of adhesive resin, 1.0 parts of adhesion promoter HMT, 2 parts of antioxidant, 3 parts of zinc oxide, 1.5 parts of stearic acid, 3.5 parts of vulcanizing agent and 1.0 parts of accelerator.

[0072] Among them, the main sources of raw materials are as follows: The natural rubber is STR20 (Thailand standard rubber); The butadiene rubber is high-cis butadiene rubber BR9000, a product of PetroChina Daqing Petrochemical Company; White carbon black is highly dispersed white carbon black, 1165MP from Qingdao Solvay, with a BET specific surface area of ​​160m 2 / g; The coupling agent TESPT is 50% SI69 mixed with N330, Jiangxi Hongbai New Materials Co., Ltd.

[0073] The sidewall main rubber 2 is prepared by mixing the raw materials including the following components based on 100 parts by weight of raw rubber: 40 parts of natural rubber, 60 parts of butadiene rubber, 35 parts of carbon black, 7 parts of environmentally friendly oil, 3.5 parts of p-phenylenediamine antioxidant, 3 parts of quinoline antioxidant, 2.0 parts of microcrystalline wax, 3 parts of zinc oxide, 1.5 parts of stearic acid, 2 parts of vulcanizing agent, and 1.0 part of accelerator.

[0074] Among them, the main sources of raw materials are as follows: The natural rubber is STR20 (Thailand standard rubber); The butadiene rubber is neodymium-based high-cis butadiene rubber NDBR, product name CB24EZ, a product of Alanxin Co., Ltd. The environmentally friendly oil is TDAE environmentally friendly oil Vivatec 500, a product of Hansheng Petrochemical (Ningbo) Co., Ltd.

[0075] The sidewall outer rubber 3 is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber: 45 parts of natural rubber, 40 parts of cis-1,4-polybutadiene rubber, 15 parts of styrene-butadiene rubber, 75 parts of carbon black, 5 parts of environmental protection oil, 2 parts of p-phenylenediamine antioxidant, 1.5 parts of quinoline antioxidant, 1.5 parts of microcrystalline wax, 3 parts of homogenizer, 3 parts of tackifying resin, 3 parts of zinc oxide, 1.5 parts of stearic acid, 2 parts of vulcanizing agent, and 2 parts of accelerator.

[0076] Among them, the sources of the main raw materials are as follows: The natural rubber is STR20 (Thai standard rubber); The cis-1,4-polybutadiene rubber is high-cis cis-1,4-polybutadiene rubber BR9000, a product of PetroChina Daqing Petrochemical Company; The tackifying resin is imported super tackifying resin KORESIN, a product of BASF Company; The homogenizer grade is 40MSF, a product of German struktol company.

[0077] The sidewall reinforcing rubber 4 is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber: 80 parts of natural rubber, 20 parts of high-cis cis-1,4-polybutadiene rubber, 8 parts of liquid reclaimed rubber, 60 parts of carbon black, 14 parts of reinforcing resin, 3 parts of methyl donor, 2 parts of p-phenylenediamine antioxidant, 3 parts of zinc oxide, 1.5 parts of stearic acid, 2 parts of vulcanizing agent, and 2 parts of accelerator.

[0078] Among them, the sources of the main raw materials are as follows: The natural rubber is STR20 (Thai standard rubber); The high-cis cis-1,4-polybutadiene rubber is neodymium-based high-cis cis-1,4-polybutadiene rubber NDBR, product name CB24EZ, a product of Arlanxeo Company; The liquid reclaimed rubber is the self-produced tread liquid reclaimed rubber T60 of Zhongce Group, a product of Zhongce Recycling Technology Company; The reinforcing resin is modified reinforcing resin SL-2101, Huaji (China) Chemical Co., Ltd.; The methyl donor is accelerator HMT, Shandong Huatai Chemical Auxiliary Co., Ltd.

[0079] Table 1 Comparison of rheological and physical properties of four rubber combinations Bead filler 1 Main sidewall rubber 2 Outer sidewall rubber 3 Reinforcing sidewall rubber 4 Shore hardness 67 56 71 88 <![CDATA[Composite modulus E * > 14.5 7.2 18.1 22.5 tanδ 0.091 0.086 0.166 0.155 Example 2 A tire with a tire specification of 155 / 65R13 73T, and the tread pattern is as Figure 6As shown, the tire includes a tread portion, a sidewall portion, a belt layer portion, and a bead portion. The sidewall portion is prepared by vulcanizing the sidewall rubber compound of Example 1. The lower width of the sidewall cushion rubber 1 is 17 mm, and the upper width is 25 mm. The width of the sidewall reinforcing rubber 4 is 18 mm smaller than the lower width of the sidewall outer protection rubber 3. The ratio of the center thickness of the sidewall outer protection rubber 3 to the center thickness of the sidewall reinforcing rubber 4 is 3:1.

[0080] Comparative Example 1 A tire with a tire size of 155 / 65R13 73T, and the tread pattern is as Figure 6 As shown, the tire includes a tread portion, a sidewall portion, a belt layer portion, and a bead portion. The sidewall portion is prepared by vulcanizing the traditional two-component sidewall rubber compound. In the traditional two-component sidewall rubber compound, the sidewall main rubber 2 uses the formula of the sidewall main rubber 2 in Example 1, and the sidewall outer protection rubber 3 uses the formula of the sidewall outer protection rubber 3 in Example 1.

[0081] The rolling resistance performance of the tires of Example 2 and Comparative Example 1 was tested respectively. The rolling resistance decreased from the original 10.3 to 9.8. The results are as Figure 1 shown, meeting the requirements of the new ECE R117 regulation.

[0082] The above is the description of the embodiments of the present invention. Through the above description of the disclosed embodiments, those skilled in the art can implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art. 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 herein, but will conform to the widest scope consistent with the principles and novel points disclosed herein.

Claims

1. A sidewall rubber with a four-composite rubber structure, characterized in that: The sidewall rubber comprises a sidewall cushion rubber (1), a sidewall main rubber (2), a sidewall outer protective rubber (3) and a sidewall reinforcing rubber (4), wherein the sidewall cushion rubber (1) is located above the sidewall main rubber (2) and supports the tire shoulder, the sidewall outer protective rubber (3) is located below the sidewall main rubber (2), and the sidewall reinforcing rubber (4) is located on the inner side of the sidewall outer protective rubber (3); The sidewall rubber (1) is a rubber composition with low heat generation, high modulus and high hardness, with a Shore hardness of 64-68 and a composite modulus E * The main rubber (2) of the sidewall adopts a low modulus rubber composition with a Shore hardness of 54-58 and a composite modulus E * The sidewall outer rubber (3) adopts a high modulus rubber composition C, with a Shore hardness of 68-72 and a composite modulus E * is 16.0-20.0mPa, tanδ is 0.14-0.18; the sidewall reinforcing rubber (4) adopts a high modulus rubber composition, Shore hardness is 80-90, and the composite modulus E * ≥20.0mPa, tanδ is 0.10-0.16; The sidewall cushion rubber (1) is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber: 60-90 parts of natural rubber, 10-40 parts of butadiene rubber, 10-30 parts of white carbon black, 25-45 parts of low heat build-up carbon black, 2-3.5 parts of silane coupling agent TESPT, 1.0-3.0 parts of adhesive resin, 0.5-1.5 parts of adhesion promoter HMT, and 1-3 parts of antioxidant; The sidewall main rubber (2) is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber: 30-50 parts of natural rubber, 50-70 parts of butadiene rubber, 25-45 parts of carbon black, 3-10 parts of environmentally friendly oil, 2-5 parts of p-phenylenediamine antioxidant, 2-4 parts of quinoline antioxidant, and 1-2.5 parts of microcrystalline wax; The sidewall outer rubber (3) is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber: 30-60 parts of natural rubber, 30-50 parts of butadiene rubber, 10-25 parts of styrene-butadiene rubber, 65-80 parts of carbon black, 3-8 parts of environmentally friendly oil, 1-3 parts of p-phenylenediamine antioxidant, 1-2 parts of quinoline antioxidant, 1-2 parts of microcrystalline wax, 2-4 parts of leveling agent, and 2-4 parts of tackifying resin; The sidewall reinforcing rubber (4) is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber: 70-90 parts of natural rubber, 10-30 parts of high-cis butadiene rubber, 5-10 parts of liquid reclaimed rubber, 50-70 parts of carbon black, 8-20 parts of reinforcing resin, 1-5 parts of methyl donor, which forms a resin network when vulcanized with the reinforcing resin, and 1-3 parts of a p-phenylenediamine antioxidant.

2. The sidewall rubber according to claim 1, characterized in that: The sidewall cushion rubber (1) is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber: 70-80 parts of natural rubber, 20-30 parts of butadiene rubber, 15-25 parts of white carbon black, 30-40 parts of low heat build-up carbon black, 2-3.5 parts of silane coupling agent TESPT, 1.0-3.0 parts of adhesive resin, 0.5-1.5 parts of adhesion promoter HMT, 1-3 parts of antioxidant, 2-4 parts of zinc oxide, 1-2 parts of stearic acid, 2.0-5.0 parts of vulcanizing agent, and 0.5-1.5 parts of accelerator; The sidewall main rubber (2) is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber: 35-45 parts of natural rubber, 55-65 parts of butadiene rubber, 30-40 parts of carbon black, 6-8 parts of environmentally friendly oil, 2-5 parts of p-phenylenediamine antioxidant, 2-4 parts of quinoline antioxidant, 1-2.5 parts of microcrystalline wax, 2-4 parts of zinc oxide, 1-2 parts of stearic acid, 1-3 parts of vulcanizing agent, and 0.5-1.5 parts of accelerator; The sidewall outer rubber (3) is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber: 40-50 parts of natural rubber, 35-45 parts of butadiene rubber, 15-20 parts of styrene-butadiene rubber, 70-80 parts of carbon black, 3-8 parts of environmentally friendly oil, 1-3 parts of p-phenylenediamine antioxidant, 1-2 parts of quinoline antioxidant, 1-2 parts of microcrystalline wax, 2-4 parts of leveling agent, 2-4 parts of tackifying resin, 2-4 parts of zinc oxide, 1-2 parts of stearic acid, 1-3 parts of vulcanizing agent, and 1-3 parts of accelerator; The sidewall reinforcing rubber (4) is prepared by mixing the following raw materials based on 100 parts by weight of raw rubber: 75-85 parts of natural rubber, 15-25 parts of high-cis butadiene rubber, 5-10 parts of liquid reclaimed rubber, 55-65 parts of carbon black, 12-16 parts of reinforcing resin, 1-5 parts of methyl donor, 1-3 parts of p-phenylenediamine antioxidant, 2-4 parts of zinc oxide, 1-2 parts of stearic acid, 1-3 parts of vulcanizing agent, and 1-3 parts of accelerator.

3. The sidewall rubber according to claim 1 or 2, characterized in that: In the sidewall cushion rubber (1), the butadiene rubber is high-cis butadiene rubber; The white carbon black is highly dispersed white carbon black with a BET specific surface area of ​​150-170m 2 / g; The low heat generation carbon black includes but is not limited to N660, N326, N550, and N375.

4. The sidewall rubber according to claim 1 or 2, characterized in that: In the sidewall main rubber (2), the butadiene rubber is preferably neodymium-based high-cis butadiene rubber; The carbon black BET specific surface area is 34-46m 2 / g, particle size is 40-48nm.

5. The tread rubber according to claim 1 or 2, characterized in that: In the sidewall outer rubber (3), the butadiene rubber is high-cis butadiene rubber; The carbon black BET specific surface area is 71-85 m 2 / g, particle size is 26-30nm; The homogenizer is a mixture of resins with different polarities and asphaltene.

6. The tread rubber according to claim 1 or 2, characterized in that: In the sidewall reinforcing rubber (4), the high-cis butadiene rubber is a neodymium-based high-cis butadiene rubber; The liquid reclaimed rubber is tread reclaimed rubber, and the mesh number of the rubber powder before the reclaimed rubber is cracked is greater than 40 meshes; The carbon black BET specific surface area is 34-46m 2 / g, particle size is 40-48nm; The methyl donor is hexamethyltetramine.

7. The sidewall rubber according to claim 1, characterized in that: The lower width of the sidewall rubber (1) is 17±3 mm, and the upper width is 25±3 mm.

8. The sidewall rubber according to claim 1, characterized in that: The width of the sidewall reinforcing rubber (4) is 15 mm to 20 mm smaller than the lower width of the sidewall outer protective rubber (3).

9. The sidewall rubber according to claim 1, characterized in that: The ratio of the center thickness of the sidewall outer protective rubber (3) to the center thickness of the sidewall reinforcing rubber (4) is (2-4):

1.

10. A tire comprising a tread portion, a sidewall portion, a belt portion and a bead portion, characterized in that: The sidewall part is prepared by vulcanizing the sidewall rubber described in any one of claims 1 to 9.

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