High-wear-resistance tread rubber for off-the-road tire

Abstract

The invention discloses high-wear-resistance tread rubber for an off-the-road tire, and relates to the technical field of tires. According to the technical scheme, the rubber composition comprises the following components in parts by weight: 100 parts of a rubber component, 35-55 parts of carbon black, 4-6 parts of a wear-resistant agent DC-Z-B, 10-20 parts of white carbon black, 1-2 parts of a silane coupling agent, 1-2 parts of alkylphenol tackifying resin, 8-12 parts of a CR multifunctional composite reinforcing agent TDS, 3-5 parts of an anti-aging agent, 1-2 parts of microcrystalline wax, 3-5 parts of zinc oxide, 1-2 parts of stearic acid, 1.5-2 parts of sulfur and 1.2-2.4 parts of an accelerant. The wear-resistant agent DC-Z-B and CR multifunctional composite reinforcing agent TDS are adopted, through interface optimization, dynamic performance complementation and thermal stability synergy, the wear resistance and tear resistance of the tread rubber can be further improved, and the comprehensive performance improvement of '1 + 1gt, 2' is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of tires, and particularly to a highly wear-resistant tread rubber for construction machinery tires. Background Art

[0002] As an indispensable important equipment in modern engineering construction, the stability and durability of the performance of construction machinery vehicles are directly related to the project progress and cost. However, during the use process, the wear and damage of tires have become common problems that trouble the industry. This not only increases the maintenance cost but also may cause potential safety hazards.

[0003] Construction machinery vehicles often face complex and changeable working environments, such as rough roads, sharp ore fragments, high-temperature and high-pressure working conditions, etc. These factors pose extremely high requirements for the wear resistance of tires. While the tires are under great pressure and friction, they also have to cope with the impact and cutting of various sharp objects, and are extremely prone to wear, tear and other damages. From the wear mechanism of mining tires, improving the abrasion resistance is the key to extending the tire life. However, simply focusing on abrasion is not enough, and the improvement of tear resistance is equally crucial. Tires with good tear resistance can better resist the impact of sharp objects, reduce tear damage, and thus indirectly improve the abrasion resistance and overall life of the tires.

[0004] When designing the formula of traditional construction machinery tire tread rubber, it is often necessary to balance wear resistance, tear resistance and heat generation performance. Especially for giant tires, the heat generation problem is particularly prominent. In order to ensure that the heat generation is within a controllable range, it is often necessary to abandon the use of styrene-butadiene rubber with better wear resistance and choose natural rubber with lower heat generation. But this brings new problems of insufficient wear resistance.

[0005] In view of the above challenges, developing a tire tread rubber that not only has high wear resistance and tear resistance but also does not have an obvious impact on heat generation has become an urgent need in the industry. Such a tread rubber can better meet the needs of construction machinery vehicles in high-intensity working environments, extend the tire life, reduce the maintenance cost, and improve the operation efficiency. Summary of the Invention

[0006] The technical problem to be solved by the present invention is: to overcome the deficiencies of the prior art and provide a highly wear-resistant tread rubber for construction machinery tires. By using wear-resistant agent DC-Z-B and CR multifunctional composite reinforcing agent TDS, through interface optimization, dynamic performance complementarity and thermal stability coordination, the wear resistance and tear resistance of the tread rubber can be further improved, realizing a comprehensive performance improvement of "1 + 1 > 2".

[0007] The technical solution of the present invention is as follows: High wear-resistant tread compound for construction machinery tires, comprising the following components in parts by weight: 100 parts of rubber component, 35 - 55 parts of carbon black, 4 - 6 parts of wear-resistant agent DC-Z-B, 10 - 20 parts of white carbon black, 1 - 2 parts of silane coupling agent, 1 - 2 parts of alkylphenol tackifying resin, 8 - 12 parts of CR multi-functional composite reinforcing agent TDS, 3 - 5 parts of anti-aging agent, 1 - 2 parts of microcrystalline wax, 3 - 5 parts of zinc oxide, 1 - 2 parts of stearic acid, 1.5 - 2 parts of sulfur, 1.2 - 2.4 parts of accelerator.

[0008] Among them, the wear-resistant agent DC-Z-B is a wear-resistant agent produced by Wuxi Dongcai Technology Co., Ltd., with an inorganic-organic hybrid structure, and its core component is nano zirconia / silicon carbide composite particles, and the surface is modified with a silane coupling agent. The CR multi-functional composite reinforcing agent TDS is a multi-functional composite reinforcing agent produced by Anhui Ruibang Rubber Technology Co., Ltd., and its main components are carboxylated styrene-butadiene latex and nano kaolin complex.

[0009] Preferably, the rubber component is natural rubber NR.

[0010] Preferably, the carbon black is one or both of N115 carbon black and N220 carbon black.

[0011] Preferably, the white carbon black is high-dispersion precipitated white carbon black 1165MP.

[0012] Preferably, the silane coupling agent is a silane mixture TESPT with 50% mass content of Si69.

[0013] Preferably, the alkylphenol tackifying resin is TYC-0412 tackifying resin.

[0014] Preferably, the anti-aging agent is ketone-amine type anti-aging agent RD and p-phenylenediamine type anti-aging agent 4020.

[0015] Preferably, the microcrystalline wax is bimodal microcrystalline wax or trimodal microcrystalline wax.

[0016] Preferably, the accelerator is a sulfenamide type accelerator or a combination of it and a thiazole type accelerator.

[0017] Compared with the prior art, the present invention has the following beneficial effects: The tread compound of the present invention uses the wear-resistant agent DC-Z-B and the CR multi-functional composite reinforcing agent TDS. In addition to their respective performance advantages, the two have a synergistic effect, and can further improve the wear resistance and tear resistance of the tread compound through interface optimization, dynamic performance complementarity and thermal stability synergy, realizing the comprehensive performance improvement of "1 + 1 > 2". Therefore, compared with the existing construction tires, the wear resistance and tear resistance of the tires using the tread compound of the present invention are significantly improved, while maintaining the original heat generation performance, greatly improving the abrasion and service life of the tires. Detailed implementation manners

[0018] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention.

[0019] Examples 1-3 and Comparative Examples 1-3 The tread rubber formulations of Examples 1-3 and Comparative Examples 1-3 are shown in Table 1: Table 1 Tread rubber formulations of Examples 1-3 and Comparative Examples 1-3

[0020] The preparation methods of the tread rubbers of Examples 1-3 and Comparative Examples 1-3 include the following steps: S1 First-stage mixing Put 100 parts of 20# standard rubber and 30 parts of carbon black N115 into a kneader and mix for 30 s. Then add wear-resistant agent DC-Z-B, CR multifunctional composite reinforcing agent TDS, alkylphenol tackifying resin TYC-0412, microcrystalline wax, zinc oxide and stearic acid, and mix at a speed of 42 rpm. Lift and press the material every 30 s. When the temperature of the rubber compound reaches 165 °C, discharge the rubber and cut it into sheets. After cooling at room temperature for 6 h, obtain the first-stage masterbatch, and then carry out the second-stage mixing on it; S2 Second-stage mixing Put the first-stage masterbatch obtained in step S1, the remaining carbon black N115, all of the white carbon black 1165MP, silane coupling agent TESPT, antioxidant 4020 and RD into a kneader, and mix at a speed of 37 rpm. Lift and press the material every 30 s. When the temperature of the rubber compound reaches 150 °C, discharge the rubber and cut it into sheets. After cooling at room temperature for 6 h, obtain the second-stage masterbatch, and then carry out the final mixing on it (if the Mooney viscosity is higher than 75 dN·m, one-stage return is required); S3 Final mixing Put the second-stage masterbatch obtained in step S2, sulfur and accelerator CZ into a kneader, and mix at a speed of 27 rpm. Lift and press the material once every 30 s, 25 s, and 20 s in sequence. When the mixing time reaches 120 s, discharge the rubber and cut it into sheets. After cooling, the high-wear-resistant tread rubber for construction machinery tires is obtained.

[0021] Perform performance tests on the tread rubbers prepared in Examples 1-3 and Comparative Examples 1-3. The test results are shown in Table 2: Table 2 Performance test results of the tread rubbers of Examples 1-3 and Comparative Examples 1-3

[0022] Comparing the data of the above examples and comparative examples, it can be seen that after simultaneously using the wear-resistant agent DC-Z-B and the CR multi-functional composite reinforcing agent TDS in the tread rubber formula, while maintaining the basic mechanical properties of the rubber compound, a significant improvement in comprehensive performance is achieved. Comparing Example 1 with Comparative Example 1, it can be seen that after adding the above two additives, the tensile strength, 100% modulus at 100% elongation, and 300% modulus at 300% elongation of the rubber compound have all increased to varying degrees, and the elongation at break and hardness are basically the same, indicating that the two additives do not sacrifice their flexibility while improving the material strength; the wear resistance has increased by 45%, and the abrasion has been significantly improved. This is mainly due to the unique structure of the nano-zirconia / silicon carbide composite particles in DC-Z-B, and the nano-particles modified by silane coupling agent on its surface form a three-dimensional interpenetrating wear-resistant skeleton in the rubber matrix, effectively resisting the microscopic cutting action of abrasive particles through Si-O-C chemical bonding. At the same time, the tear strength of Example 1 has increased by about 30%, which benefits from the composite design of carboxylated styrene-butadiene latex and nano-kaolin in TDS. Its rubber phase forms an energy dissipation network through molecular chain entanglement, and the nano-sheets hinder crack propagation through two-dimensional confinement effect. In terms of thermal performance, the final fatigue temperature rise of Example 1 is 33°C, which is basically the same as that of Comparative Example 1. This is because the thermal stability of DC-Z-B ensures the structural integrity at high temperatures, and the oriented arrangement of nano-kaolin in TDS constructs an efficient heat conduction path, realizing the rapid dissipation of dynamic heat generation.

[0023] At the same time, by comparing Example 1 with Comparative Examples 2-3, it can be found that although Comparative Example 2 using only DC-Z-B has good abrasion performance, its tear strength is only 58 KN / m; while Comparative Example 3 using only TDS has a tear strength of 63 KN / m, but the abrasion value reaches 0.35 cm³ / 1.61 km, and neither can achieve the excellent effects of the two materials used together.

[0024] The synergistic effect of the above two additives stems from the fact that the carboxylated styrene-butadiene latex molecules of TDS can wrap the DC-Z-B nanoparticles through hydrogen bonding, preventing their aggregation caused by Brownian motion. At the same time, the interfacial bonding force between the filler and the rubber is enhanced through an esterification reaction. Under TEM observation, zirconia / silicon carbide particles with a size of 50-200 nm are evenly embedded in a rubber network with a size of 100-500 nm, forming a perfect "rigid-flexible interlocking" protection system: the nanoceramic phase of DC-Z-B acts as a "hard anchor point" to resist surface wear, and the elastic rubber phase of TDS acts as an "energy trap" to absorb impact stress. The market test results show that the wear life of the tire using the tread rubber of the present invention is significantly improved, fully verifying the use value of the synergistic effect of DC-Z-B and TDS. The essence of this synergistic effect lies in the complementarity of the two additives in molecular design: DC-Z-B provides "point-like reinforcement" through nano-scale inorganic particles, focusing on improving the interfacial wear resistance; TDS constructs a "network support" through micro-scale rubber-clay composites, mainly enhancing the tear resistance of the matrix phase. Through the interfacial chemical reaction between silane and carboxyl and multi-scale structure assembly, the performance is synergistically multiplied, achieving a modification effect of "1+1>2".

Claims

1. High wear-resistant tread rubber for construction machinery tires, characterized in that, Comprising the following components in parts by weight: 100 parts of rubber component, 35 - 55 parts of carbon black, 4 - 6 parts of wear-resistant agent DC-Z-B, 10 - 20 parts of white carbon black, 1 - 2 parts of silane coupling agent, 1 - 2 parts of alkylphenol tackifying resin, 8 - 12 parts of CR multi-functional composite reinforcing agent TDS, 3 - 5 parts of antioxidant, 1 - 2 parts of microcrystalline wax, 3 - 5 parts of zinc oxide, 1 - 2 parts of stearic acid, 1.5 - 2 parts of sulfur, 1.2 - 2.4 parts of accelerator.

2. The high wear-resistant tread rubber for construction machinery tires according to claim 1, characterized in that, The rubber component is natural rubber NR.

3. The high wear-resistant tread rubber for construction machinery tires according to claim 1, wherein The carbon black is one or both of N115 carbon black and N220 carbon black.

4. The high wear-resistant tread rubber for construction machinery tires according to claim 1, characterized in that The white carbon black is white carbon black 1165MP.

5. The high wear-resistant tread rubber for construction machinery tires according to claim 1, characterized in that, The silane coupling agent is silane mixture TESPT.

6. The high wear-resistant tread rubber for construction machinery tires according to claim 1, characterized in that The alkylphenol tackifying resin is TYC-0412 tackifying resin.

7. The high wear-resistant tread rubber for construction machinery tires according to claim 1, wherein, The antioxidant is ketoneamine antioxidant RD and p-phenylenediamine antioxidant 4020.

8. The high wear-resistant tread rubber for construction machinery tires according to claim 1, wherein The microcrystalline wax is bimodal microcrystalline wax or trimodal microcrystalline wax.

9. The high wear-resistant tread rubber for construction machinery tires according to claim 1, characterized in that, The accelerator is a sulfenamide accelerator or a combination thereof with a thiazole accelerator.

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