Anti-aging truck radial tire tread rubber and preparation method thereof

Abstract

The invention provides anti-aging radial truck tire tread rubber and a preparation method thereof. The tread rubber is prepared from 100 parts of natural rubber, 45 to 70 parts of filler, 0.5 to 2 parts of aromatic oil, 1 to 4 parts of silane coupling agent, 1 to 2 parts of rubber protection wax, 1 to 5 parts of homogenizing agent, 4 to 8 parts of vulcanizing activator, 2 to 4 parts of anti-aging agent, 0.5 to 2 parts of anti-reversion vulcanizing agent, 0.8 to 2 parts of sulfur, 1 to 2 parts of accelerant and 0.1 to 0.5 part of scorch retarder. According to the anti-aging truck radial tire tread rubber and the preparation method thereof, the anti-reversion vulcanizing agent PSO-35 is added into the natural rubber, and the anti-reversion vulcanizing agent is long in molecular chain, can have good compatibility with the rubber and is not prone to blooming and precipitation; according to the anti-reversion vulcanizing agent, a novel cross-linking bond formed by connecting a polysulfide bond and a flexible bond is introduced, so that the reversion resistance and the aging resistance of rubber are improved; the anti-reversion vulcanizing agent is introduced with a flexible group, so that the flexural fatigue resistance of rubber can be improved.

Description

Technical Field

[0001] The invention relates to the technical field of tread rubber, and in particular to an aging-resistant load-carrying radial tire tread rubber and a preparation method thereof. Background Art

[0002] All-steel radial tires use steel cord and radial structure, with excellent high load capacity, can withstand long-term heavy-load driving. The tread rubber is the part of the tire that directly contacts the ground, and needs to have good wear resistance, grip, puncture resistance, low rolling resistance, low heat generation, and good anti-aging performance.

[0003] Improving the aging resistance of tread rubber can maintain the long-term performance of load-bearing radial tires. Usually, chemical antioxidants are used in tread rubber to inhibit the oxidation reaction of rubber molecular chains, thereby slowing down the aging process of rubber. However, the polysulfide bonds produced by cross-linking sulfur-vulcanized rubber will produce vulcanization reversion during long-term use, resulting in reduced tire performance. Summary of the invention

[0004] The purpose of the present invention is to overcome the deficiencies in the prior art and provide an aging-resistant load-bearing radial tire tread rubber and a preparation method thereof. The anti-reversion vulcanizing agent PSO-35 product is applied to rubber to maintain good compatibility with the rubber, improve the rubber's anti-vulcanization reversion and aging resistance, and improve the rubber's fatigue resistance.

[0005] The technical solution adopted by the present invention is:

[0006] An aging-resistant load-bearing radial tire tread rubber, characterized in that it includes 100 parts of natural rubber, 45-70 parts of filler, 0.5-2 parts of aromatic oil, 1-4 parts of silane coupling agent, 1-2 parts of rubber protective wax, 1-5 parts of leveling agent, 4-8 parts of vulcanization activator, 2-4 parts of antioxidant, 0.5-2 parts of anti-reversion vulcanizing agent, 0.8-2 parts of sulfur, 1-2 parts of accelerator, and 0.1-0.5 parts of scorch retarder.

[0007] Preferably, in the tread rubber of the ageing-resistant load-bearing radial tire, the filler comprises 40-50 parts of carbon black and 5-20 parts of white carbon black.

[0008] Preferably, in the tread rubber of the ageing-resistant load-carrying radial tire, the silane coupling agent is Si69.

[0009] Preferably, in the tread rubber of the ageing-resistant load-bearing radial tire, the antioxidant comprises 1-2 parts of antioxidant RD and 1-2 parts of antioxidant 4020.

[0010] Preferably, in the tread rubber of the ageing-resistant load-carrying radial tire, the accelerator is accelerator CZ.

[0011] Preferably, in the tread rubber of the ageing-resistant load-carrying radial tire, the anti-scorching agent is anti-scorching agent CTP.

[0012] Preferably, in the aging-resistant load-bearing radial tire tread rubber, the vulcanization activator comprises 3-5 parts of zinc oxide and 1-3 parts of stearic acid.

[0013] The present invention also provides a method for preparing an aging-resistant load-carrying radial tire tread rubber, which comprises the following steps:

[0014] (1) One-stage mixing: natural rubber is put into an internal mixer for primary mixing, and then carbon black, white carbon black, silane coupling agent, aromatic oil, zinc oxide, stearic acid, antioxidant, rubber protective wax, and homogenizer are added for secondary mixing. The secondary mixing is performed until the temperature reaches 160-165° C., and the discharged rubber is rolled on an open mixer to obtain a masterbatch;

[0015] (2) Masterbatch standing: The masterbatch obtained from the first mixing step is placed in the air to cool for 4-8 hours;

[0016] (3) Final refining: The masterbatch is rolled on an open mixing mill for 1-1.5 min, and then anti-scorch agent, sulfur, accelerator, and anti-reversion vulcanizing agent are added. Then, the masterbatch is rolled on a mixing mill for 1.5-2 min, and the left and right cutters are used 2-5 times. The roller distance is adjusted to the minimum, and the masterbatch is triangularly packaged, rolled, and unrolled to obtain the finished tread rubber.

[0017] Preferably, in the method for preparing the aging-resistant load-bearing radial tire tread rubber, the secondary mixing in step (1) is specifically as follows: controlling the speed of the internal mixer to 60-90 rpm, mixing to 100-120°C and then lifting the top bolt, then controlling the speed to 60-90 rpm, mixing to 125-135°C and then lifting the top bolt, then controlling the speed to 60-90 rpm, mixing to 140-155°C and then lifting the top bolt, and finally controlling the speed to 60-90 rpm, mixing to 160-165°C and then draining the rubber.

[0018] Preferably, in the method for preparing the tread rubber of the ageing-resistant load-carrying radial tire, the temperature of the rolling mill in step (3) is 105-110° C., and the roller distance of the rolling mill is 3.8-4.2 mm.

[0019] Advantages of the present invention:

[0020] The aging-resistant load-carrying radial tire tread rubber and the preparation method thereof are characterized in that the molecular structure of the anti-reversion vulcanizing agent contains a long-chain structure, which has good compatibility with the long-chain structure of rubber. When applied to the load-carrying radial tire tread rubber formula, it is not easy to precipitate and cause blooming. The anti-reversion vulcanizing agent PSO-35 can synergize with the vulcanization accelerator, sulfur, and rubber molecules to generate cross-linked bonds containing flexible bonds (-S X-R-), compared with the traditional single sulfur bond (-S-), polysulfide bond (-S X -) cross-linked structure, has better resistance to vulcanization reversion and aging, and also has better resistance to flexural fatigue. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a comparison diagram of rheological curves of embodiments and comparative examples.

[0022] Figure 2 It is a comparison chart of DMA curves of embodiment and comparative example.

[0023] Figure 3 It is a partial enlarged comparison diagram of the DMA curves of the embodiment and the comparative example near 60°C.

[0024] Figure 4 It is a comparison chart of loss factor tanδ@60℃ between the embodiment and the comparative example.

[0025] Figure 5 It is a comparison chart of compression heat generation of the embodiment and the comparative example.

[0026] Figure 6 It is a comparison chart of DIN wear of the embodiment and the comparative example. DETAILED DESCRIPTION

[0027] The present invention will be further described below in conjunction with specific embodiments.

[0028] The anti-reversion vulcanizing agent in the following examples and comparative examples has the following molecular structure:

[0029]

[0030] R is a flexible alkane chain. The manufacturer of the anti-reversion vulcanizing agent is Shanghai Qixiang New Material Technology Co., Ltd., and the brand name is PSO-35.

[0031] Example 1

[0032] A tread rubber for a load-bearing radial tire resistant to aging comprises 100 parts of natural rubber, 43 parts of carbon black, 15 parts of white carbon black, 1.0 part of aromatic oil, 3.0 parts of silane coupling agent Si69, 1.0 part of rubber protective wax, 2.0 parts of a leveling agent, 3.0 parts of zinc oxide, 2.0 parts of stearic acid, 1.0 part of an antioxidant RD, 1.8 parts of an antioxidant 4020, 1.0 part of an anti-reversion vulcanizing agent, 1.2 parts of sulfur, 1.4 parts of an accelerator CZ, and 0.1 part of a scorch retarder CTP. The leveling agent is produced by Jiangsu Ruiba New Material Technology Co., Ltd. and the brand is RH-100.

[0033] The method for preparing the tread rubber of the aging-resistant load-carrying radial tire of the present embodiment comprises the following steps:

[0034] (1) One-stage mixing: natural rubber is put into an internal mixer for one-stage mixing, with a top bolt pressure of 0.30 MPa, a rotation speed of 60 rpm, and a mixing time of 30 s. Then, carbon black, white carbon black, silane coupling agent, aromatic oil, zinc oxide, stearic acid, antioxidant, rubber protective wax, and homogenizer are added for secondary mixing, with a rotation speed of 60 rpm and mixing for 30 s. Then, the speed of the internal mixer is controlled to 80 rpm, and the top bolt is lifted when the mixing temperature reaches 110° C., and then the top bolt is lifted when the mixing speed is maintained at 80 rpm. Then, the top bolt is lifted when the mixing temperature reaches 130° C., and then the top bolt is lifted when the mixing speed is maintained at 80 rpm. Then, the top bolt is lifted when the mixing temperature reaches 150° C., and finally, the top bolt is lifted when the mixing speed is maintained at 80 rpm. The rubber is discharged and rolled off on an open mixer to obtain a masterbatch.

[0035] (2) Masterbatch standing: The masterbatch obtained from the first mixing step is placed in air to cool for 4 hours;

[0036] (3) Final refining: The masterbatch is rolled on an open mixing mill for 1.5 min, and then anti-scorch agent, sulfur, accelerator, and anti-reversion vulcanizing agent are added. Then, the masterbatch is rolled on an open mixing mill for 2 min, and the left and right cutters are cut 3 times each. The roller distance is adjusted to the minimum, and a triangular package is made. Then, the masterbatch is rolled and unrolled to obtain a finished tread rubber. The rolling temperature of the open mixing mill is 105°C, the roller distance of the open mixing mill is 4.2 mm, and the speed ratio of the front and rear rollers is 1:1.4.

[0037] Example 2

[0038] An aging-resistant load-carrying radial tire tread rubber comprises 100 parts of natural rubber, 43 parts of carbon black, 15 parts of white carbon black, 1.0 parts of aromatic oil, 3.0 parts of silane coupling agent Si69, 1.0 parts of rubber protective wax, 2.0 parts of leveling agent, 3.0 parts of zinc oxide, 2.0 parts of stearic acid, 1.0 parts of antioxidant RD, 1.8 parts of antioxidant 4020, 1.0 parts of anti-reversion vulcanizing agent, 1.0 parts of sulfur, 1.4 parts of accelerator CZ and 0.1 parts of scorch retarder CTP.

[0039] The method for preparing the tread rubber of the aging-resistant load-carrying radial tire of the present embodiment comprises the following steps:

[0040] (1) One-stage mixing: natural rubber is put into an internal mixer for one-stage mixing, with a top bolt pressure of 0.30 MPa, a rotation speed of 60 rpm, and a mixing time of 30 s. Then, carbon black, white carbon black, silane coupling agent, aromatic oil, zinc oxide, stearic acid, antioxidant, rubber protective wax, and homogenizer are added for secondary mixing, with a rotation speed of 60 rpm and mixing for 30 s. Then, the speed of the internal mixer is controlled to 80 rpm, and the top bolt is lifted when the mixing temperature reaches 110° C., and then the top bolt is lifted when the mixing speed is maintained at 80 rpm. Then, the top bolt is lifted when the mixing temperature reaches 130° C., and then the top bolt is lifted when the mixing speed is maintained at 80 rpm. Then, the top bolt is lifted when the mixing temperature reaches 150° C., and finally, the top bolt is lifted when the mixing speed is maintained at 80 rpm. The rubber is discharged and rolled off on an open mixer to obtain a masterbatch.

[0041] (2) Masterbatch standing: The masterbatch obtained from the first mixing step is placed in air to cool for at least 4 hours;

[0042] (3) Final refining: The masterbatch is rolled on an open mixing mill for 1.5 min, and then anti-scorch agent, sulfur, accelerator, and anti-reversion vulcanizing agent are added. Then, the masterbatch is rolled on an open mixing mill for 2 min, and the left and right cutters are cut 3 times each. The roller distance is adjusted to the minimum, and a triangular package is made. Then, the masterbatch is rolled and unrolled to obtain a finished tread rubber. The rolling temperature of the open mixing mill is 105°C, the roller distance of the open mixing mill is 4.2 mm, and the speed ratio of the front and rear rollers is 1:1.4.

[0043] Example 3

[0044] An aging-resistant load-carrying radial tire tread rubber comprises 100 parts of natural rubber, 43 parts of carbon black, 15 parts of white carbon black, 1.0 parts of aromatic oil, 3.0 parts of silane coupling agent Si69, 1.0 parts of rubber protective wax, 2.0 parts of leveling agent, 3.0 parts of zinc oxide, 2.0 parts of stearic acid, 1.0 parts of antioxidant RD, 1.8 parts of antioxidant 4020, 1.5 parts of anti-reversion vulcanizing agent, 0.8 parts of sulfur, 1.4 parts of accelerator CZ and 0.1 parts of scorch retarder CTP.

[0045] The method for preparing the tread rubber of the aging-resistant load-carrying radial tire of the present embodiment comprises the following steps:

[0046] (1) One-stage mixing: natural rubber is put into an internal mixer for one-stage mixing, with a top bolt pressure of 0.30 MPa, a rotation speed of 60 rpm, and a mixing time of 30 s. Then, carbon black, white carbon black, silane coupling agent, aromatic oil, zinc oxide, stearic acid, antioxidant, rubber protective wax, and homogenizer are added for secondary mixing, with a rotation speed of 60 rpm and mixing for 30 s. Then, the speed of the internal mixer is controlled to 80 rpm, and the top bolt is lifted when the mixing temperature reaches 110° C., and then the top bolt is lifted when the mixing speed is maintained at 80 rpm. Then, the top bolt is lifted when the mixing temperature reaches 130° C., and then the top bolt is lifted when the mixing speed is maintained at 80 rpm. Then, the top bolt is lifted when the mixing temperature reaches 150° C., and finally, the top bolt is lifted when the mixing speed is maintained at 80 rpm. The rubber is discharged and rolled off on an open mixer to obtain a masterbatch.

[0047] (2) Masterbatch standing: The masterbatch obtained from the first mixing step is placed in air to cool for at least 4 hours;

[0048] (3) Final refining: The masterbatch is rolled on an open mixing mill for 1.5 min, and then anti-scorch agent, sulfur, accelerator, and anti-reversion vulcanizing agent are added. Then, the masterbatch is rolled on an open mixing mill for 2 min, and the left and right cutters are cut 3 times each. The roller distance is adjusted to the minimum, and a triangular package is made. Then, the masterbatch is rolled and unrolled to obtain a finished tread rubber. The rolling temperature of the open mixing mill is 105°C, the roller distance of the open mixing mill is 4.2 mm, and the speed ratio of the front and rear rollers is 1:1.4.

[0049] Example 4

[0050] An aging-resistant load-carrying radial tire tread rubber comprises 100 parts of natural rubber, 43 parts of carbon black, 15 parts of white carbon black, 1.0 parts of aromatic oil, 3.0 parts of silane coupling agent Si69, 1.0 parts of rubber protective wax, 2.0 parts of leveling agent, 3.0 parts of zinc oxide, 2.0 parts of stearic acid, 1.0 parts of antioxidant RD, 1.8 parts of antioxidant 4020, 1.5 parts of anti-reversion vulcanizing agent, 1.0 parts of sulfur, 1.8 parts of accelerator CZ and 0.1 parts of scorch retarder CTP.

[0051] The method for preparing the tread rubber of the aging-resistant load-carrying radial tire of the present embodiment comprises the following steps:

[0052] (1) One-stage mixing: natural rubber is put into an internal mixer for one-stage mixing, with a top bolt pressure of 0.30 MPa, a rotation speed of 60 rpm, and a mixing time of 30 s. Then, carbon black, white carbon black, silane coupling agent, aromatic oil, zinc oxide, stearic acid, antioxidant, rubber protective wax, and homogenizer are added for secondary mixing, with a rotation speed of 60 rpm and mixing for 30 s. Then, the speed of the internal mixer is controlled to 80 rpm, and the top bolt is lifted when the mixing temperature reaches 110° C., and then the top bolt is lifted when the mixing speed is maintained at 80 rpm. Then, the top bolt is lifted when the mixing temperature reaches 130° C., and then the top bolt is lifted when the mixing speed is maintained at 80 rpm. Then, the top bolt is lifted when the mixing temperature reaches 150° C., and finally, the top bolt is lifted when the mixing speed is maintained at 80 rpm. The rubber is discharged and rolled off on an open mixer to obtain a masterbatch.

[0053] (2) Masterbatch standing: The masterbatch obtained from the first mixing step is placed in air to cool for at least 4 hours;

[0054] (3) Final refining: The masterbatch is rolled on an open mixing mill for 1.5 min, and then anti-scorch agent, sulfur, accelerator, and anti-reversion vulcanizing agent are added. Then, the masterbatch is rolled on an open mixing mill for 2 min, and the left and right cutters are cut 3 times each. The roller distance is adjusted to the minimum, and a triangular package is made. Then, the masterbatch is rolled and unrolled to obtain a finished tread rubber. The rolling temperature of the open mixing mill is 105°C, the roller distance of the open mixing mill is 4.2 mm, and the speed ratio of the front and rear rollers is 1:1.4.

[0055] Comparative Example

[0056] The difference between the comparative example and Example 1 is that no anti-reversion vulcanizing agent is added.

[0057] The aging-resistant load-carrying radial tire tread rubbers of Example 1, Example 2, Example 3, Example 4 and the comparative example were subjected to performance tests. The test results are shown in Tables 1, 2 and Figure 1-4 shown.

[0058] Table 1 is a table of comparative data of physical properties of the examples and comparative examples, and Table 2 is a table of comparative rheological properties of the examples 1-4 and comparative examples. Figure 1 is a comparison diagram of rheological curves of Examples 1-4 and Comparative Example; Figure 2It is a comparison chart of DMA curves of Examples 1-4 and Comparative Example, Figure 3 is a comparison chart of loss factor tanδ@60℃ between Examples 1-4 and the comparative example, Figure 4 This is a comparison chart of compression heat generation between Examples 1-4 and the comparative example. Figure 5 It is a comparison chart of the wear of Examples 1-4 and the comparative example DIN.

[0059] Table 1 Comparison of physical properties of examples and comparative examples

[0060]

[0061] Table 2 Comparison of rheological properties of examples and comparative examples

[0062]

[0063] From the comparative data of rubber properties in Table 1, it can be seen that after the aging-resistant load-bearing radial tire tread rubber uses the anti-reversion vulcanizing agent PSO-35, the tear strength of the rubber materials of each embodiment before aging is generally improved, and the tensile permanent deformation resistance of embodiment 2, embodiment 3, and embodiment 4 is improved; after aging, the tear strength of embodiment 1, embodiment 2, and embodiment 3 is higher than that of the comparative example, and the flexural crack resistance of embodiment 1, embodiment 2, and embodiment 4 is significantly higher than that of the comparative example; under the aging condition of 100°C*48h, the aging coefficient of the comparative example is 0.6132, and the aging coefficients of embodiment 1, embodiment 2, embodiment 3, and embodiment 4 increase to 0.6758, 0.7023, 0.7274, and 0.6799, respectively, and the aging resistance is improved by 10%-18%. After 300,000 times of flexural fatigue, the aging coefficients of embodiment 1, embodiment 2, and embodiment 4 are still higher than those of the comparative example.

[0064] From the rheological properties of the embodiments and comparative examples in Table 2, Figure 1From the rheological curves of the embodiment and the comparative example, it can be seen that the flatness of the vulcanization curve of the embodiment is significantly better than that of the comparative example. Under the conditions of 151°C and 60 minutes of vulcanization, the vulcanization reversion rate of the comparative example rubber is 3.35%, while the vulcanization reversion rates of Example 1, Example 2, Example 3, and Example 4 are 1.32%, 0.79%, 0.37%, and 0.28%, respectively, which are significantly lower than those of the comparative example, that is, the anti-reversion performance of the rubber of the embodiment is significantly improved; from the rheological curve, it can be seen that compared with the comparative example, when 1.0 part of PSO-35 is added alone, the vulcanization reversion rate of the comparative example rubber is 3.35%. In Example 1, the vulcanization speed of the rubber is slightly increased, and the MH of the rubber is increased, that is, the degree of vulcanization and crosslinking of the rubber is increased; in Example 2, in which 1.0 part of PSO-35 is added and 0.2 part of sulfur is subtracted, and in Example 3, in which 1.5 parts of PSO-35 is added and 0.4 parts of sulfur is subtracted, the vulcanization speed and MH of the rubber are equivalent to those of the comparative example; in Example 4, in which 1.5 parts of PSO-35 is added alone and 0.2 parts of sulfur is subtracted and 0.4 parts of CZ is added, the MH of the rubber is increased, and the flatness of the vulcanization curve is optimal.

[0065] from Figure 2 , Figure 3 and Figure 4 It can be seen that, except for the loss factor tanδ@60℃ of Example 3 which is slightly higher than that of the comparative example, the loss factors tanδ@60℃ of the other examples are lower than those of the comparative example, which means that their dynamic heat generation is lower. Figure 5 The compression heat generation data of the rubber compound show that the compression heat generation of the rubber compound of each embodiment is lower than that of the comparative example; Figure 6 The DIN wear performance of the embodiments and the comparative examples is shown. Before aging, the DIN wear amounts of embodiments 1 and 2 are lower than those of the comparative examples, and the DIN wear amounts of embodiments 3 and 4 are slightly higher than those of the comparative examples. However, after aging, the DIN wear amounts of the embodiments are lower than those of the comparative examples, that is, the aging-resistant wear performance of the embodiments is better.

[0066] Finally, it should be noted that the above specific implementation methods are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. An ageing-resistant load-carrying radial tire tread rubber, characterized in that: It includes 100 parts of natural rubber, 45-70 parts of filler, 0.5-2 parts of aromatic oil, 1-4 parts of silane coupling agent, 1-2 parts of rubber protective wax, 1-5 parts of homogenizer, 4-8 parts of vulcanization activator, 2-4 parts of antioxidant, 0.5-2 parts of anti-reversion vulcanizing agent, 0.8-2 parts of sulfur, 1-2 parts of accelerator and 0.1-0.5 parts of scorch retarder.

2. The aging-resistant load-carrying radial tire tread rubber according to claim 1, characterized in that: The filler comprises 40-50 parts of carbon black and 5-20 parts of white carbon black.

3. The aging-resistant load-carrying radial tire tread rubber according to claim 1, characterized in that: The silane coupling agent is Si69.

4. The aging-resistant load-carrying radial tire tread rubber according to claim 1, characterized in that: The antioxidant includes 1-2 parts of antioxidant RD and 1-2 parts of antioxidant 4020.

5. The aging-resistant load-carrying radial tire tread rubber according to claim 1, characterized in that: The accelerator is accelerator CZ.

6. The aging-resistant load-carrying radial tire tread rubber according to claim 1, characterized in that: The anti-scorching agent is anti-scorching agent CTP.

7. The aging-resistant load-carrying radial tire tread rubber according to claim 1, characterized in that: The vulcanization activator includes 3-5 parts of zinc oxide and 1-3 parts of stearic acid.

8. The method for preparing the tread rubber for a load-bearing radial tire resistant to aging according to any one of claims 1 to 7, characterized in that: The following steps are involved: (1) Primary mixing: natural rubber is put into an internal mixer for primary mixing, and then carbon black, white carbon black, silane coupling agent, aromatic oil, zinc oxide, stearic acid, antioxidant, rubber protective wax and homogenizer are added for secondary mixing. The secondary mixing is performed until the temperature reaches 160-165°C and the discharged rubber is rolled on an open mixer to obtain a primary masterbatch. (2) Masterbatch standing: The masterbatch obtained from the first stage of mixing is placed in the air to cool for 4-8 hours; (3) Final refining: The masterbatch is rolled on an open mixing mill for 1-1.5 min, and then anti-scorch agent, sulfur, accelerator, and anti-reversion vulcanizing agent are added. The masterbatch is rolled on an open mixing mill for 1.5-2 min, and the left and right cuts are performed 2-5 times. The roller distance is adjusted to the minimum, and the masterbatch is triangularly packaged, rolled, and unrolled to obtain the finished tread rubber.

9. The method for preparing the tread rubber of a load-carrying radial tire resistant to aging according to claim 8, characterized in that: The secondary mixing in step (1) is specifically as follows: controlling the speed of the internal mixer to 60-90 rpm, mixing to 100-120°C and lifting the top bolt, then controlling the speed to 60-90 rpm, mixing to 125-135°C and lifting the top bolt, then controlling the speed to 60-90 rpm, mixing to 140-155°C and lifting the top bolt, and finally controlling the speed to 60-90 rpm, mixing to 160-165°C for debonding.

10. The method for preparing the tread rubber of a load-carrying radial tire resistant to aging according to claim 8, characterized in that: In step (3), the mixing temperature of the open mill rollers is 105-110° C., and the mixing mill roller distance is 3.8-4.2 mm.

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