Tire with improved conductivity

Abstract

The present invention provides a tire with improved conductivity, and relates to the technical field of tire rubber manufacturing methods, the tire comprises a crown rubber, a sidewall rubber and a transition layer rubber, and the crown rubber, the sidewall rubber and the transition layer rubber comprise the following components: a rubber matrix, carbon black, an activator, a vulcanizing agent and iron powder. The technical problems that a tire prepared from a rubber composition in the prior art is lack of conductive components, low in conductivity and capable of influencing the performance of electronic equipment or causing safety accidents are solved, and the technical effects of improving the conductivity, solving the problem of electrostatic charge accumulation and improving the overall performance and safety of the tire are achieved.

Description

Technical Field

[0001] The invention relates to the technical field of tire rubber manufacturing methods, and in particular to a tire with improved electrical conductivity. Background Art

[0002] On highways and other roads, when vehicles are traveling at high speeds, the continuous friction between the tires and the ground will cause charge accumulation. When the resistivity of the tires is high, the accumulated charge is difficult to extract, resulting in a large accumulation of charge between the tires and the ground, which eventually causes electrostatic discharge. For ordinary vehicles, this electrostatic discharge may interfere with the normal operation of on-board electronic equipment, leading to problems such as abnormal navigation signals and instrument panel display errors, affecting the driving experience and driving safety. However, for special vehicles such as tank trucks, flammable and explosive goods transport vehicles, and hazardous chemicals transport vehicles, once electrostatic discharge occurs, it is very likely to cause a fire or even an explosion, causing immeasurable losses to the lives of people on the road and the safety of surrounding property.

[0003] At present, most tire bodies are mainly made of rubber composites. Although rubber itself is an excellent insulating material, no other conductive components are deliberately added to the traditional tire formula; however, the low conductivity of this conventional tire rubber composite material causes the vehicle to easily accumulate static electricity during driving. The accumulation of static electricity not only interferes with the electronic equipment on the vehicle and affects its normal operation, but also in some special circumstances, such as in flammable and explosive environments such as gas stations, static discharge may cause serious safety accidents, posing a huge threat to the safety of people and property. Summary of the invention

[0004] The purpose of the present invention is to provide a tire with improved electrical conductivity to alleviate the technical problems existing in the prior art that tires prepared from rubber compositions lack electrical conductivity components, have low electrical conductivity, affect electronic equipment or cause safety accidents.

[0005] To achieve the above object, the technical solution of the present invention is as follows:

[0006] The present invention provides a tire with improved electrical conductivity, comprising a cap rubber, a sidewall rubber and a transition layer rubber;

[0007] The cap rubber, sidewall rubber and transition layer rubber all include the following components:

[0008] Rubber matrix, carbon black, activator, vulcanizing agent and iron powder.

[0009] Furthermore, the crown rubber is composed of the following components in parts by weight: 100 parts of rubber matrix; 45-50 parts of carbon black; 5.5-6 parts of activator; 2.2-2.5 parts of vulcanizer; and 4-8 parts of iron powder.

[0010] Further, the sidewall rubber is composed of the following components by weight parts: 100 parts of rubber matrix; 35 - 40 parts of carbon black; 4 - 5 parts of activator; 2.5 - 3 parts of vulcanizing agent; 1 - 3 parts of iron powder.

[0011] Further, the transition layer rubber is composed of the following components by weight parts: 100 parts of rubber matrix; 50 - 55 parts of carbon black; 5 - 8 parts of activator; 4 - 6 parts of vulcanizing agent; 4 - 8 parts of iron powder.

[0012] Further, the rubber matrix includes at least one of natural rubber, cis - butadiene rubber or bromobutyl rubber.

[0013] Further, the activator is composed of zinc oxide and stearic acid in a mass ratio of 2.5 - 7:1 - 3.

[0014] Further, the vulcanizing agent is composed of accelerator and sulfur in a mass ratio of 0.6 - 1.2:1 - 5.4.

[0015] Further, the accelerator includes at least one of sulfenamides, thiazoles, thiurams, thioureas, dithiocarbamates, aldehyde - amines, guanidines or xanthates.

[0016] Further, the particle size D50 of the iron powder is 0.1 μm - 2 μm.

[0017] Beneficial effects:

[0018] The present invention provides a tire for improving electrical conductivity, including a crown rubber, a sidewall rubber and a transition layer rubber. The crown rubber, the sidewall rubber and the transition layer rubber all include the following components: rubber matrix, carbon black, activator, vulcanizing agent and iron powder.

[0019] In the preparation of the crown rubber, the sidewall rubber and the transition layer rubber of the tire of the present invention, iron powder is added. By utilizing the ferromagnetism of the iron powder and guiding it through a magnetic field during the mixing process, the dispersion of iron in the rubber can be greatly improved. The evenly dispersed iron powder particles form an electrical conductive network in the rubber, effectively reducing the electrostatic accumulation generated during the use of the tire, and significantly reducing the potential safety hazards brought by electrostatic discharge. Whether it is to prevent electronic devices from being interfered with in ordinary vehicles or to prevent fire and explosion accidents in special vehicles, it can be improved by enhancing the electrical conductivity.

[0020] In addition, when combined with intelligent sensors, due to the addition of iron powder, it can promote charge transfer, effectively solving the problems of signal shielding and insensitive signal transmission of sensors in the tire. On the one hand, it realizes the quality monitoring during the tire production process, ensuring product quality; on the other hand, during the use of the tire, it can monitor the tire performance in real - time, such as tire pressure, temperature, wear degree, load, providing accurate information for the driver, early warning potential risks, and ensuring the safe driving of the vehicle. Brief Description of the Drawings

[0021] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0022] Figure 1 It is a schematic diagram of the current-carrying path of a tire for improving electrical conductivity provided by an embodiment of the present invention.

[0023] Reference numerals: 100 - rim; 200 - transition layer rubber; 300 - sidewall rubber; 400 - crown rubber; 500 - road surface. Detailed Embodiments

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. For those not specified in the embodiments, they shall be carried out according to conventional conditions or the conditions recommended by the manufacturer. The reagents or instruments not specified by the manufacturer are all conventional products that can be obtained through commercial purchase.

[0025] In a first aspect, the present invention provides a tire for improving electrical conductivity, and its schematic diagram of the current-carrying path from the rim 100 to the road surface 500 is as Figure 1 shown. The main conductive rubber includes the crown rubber 400, the sidewall rubber 300, and the transition layer rubber 200. The crown rubber, the sidewall rubber, and the transition layer rubber all include the following components: a rubber matrix, carbon black, an activator, a vulcanizing agent, and iron powder.

[0026] It should be noted that in the crown rubber, by weight, 100 parts of the rubber matrix; 45 - 50 parts of carbon black; 5.5 - 6 parts of the activator; 2.2 - 2.5 parts of the vulcanizing agent; 4 - 8 parts of iron powder. In the rubber composition, 100 parts of the rubber matrix is the main body. Due to the excellent elasticity of the rubber, the tire tread can be appropriately deformed when contacting the ground, increasing the contact area with the ground, and providing excellent grip in dry, wet, snowy and other road conditions, ensuring vehicle controllability and driving safety. Adding 45 - 50 parts of carbon black can enhance the tear resistance of the tread, effectively resist damage, and improve the reliability and safety of the tire. 5.5 - 6 parts of the activator can ensure that 2.2 - 2.5 parts of the vulcanizing agent are uniformly vulcanized in the tread rubber compound, making the performance of each part of the tread consistent, and ensuring the overall quality and performance stability of the tire.

[0027] When 4 to 8 parts of iron powder are added to the crown rubber 400 of the tire tread, static electricity is easily accumulated when the crown rubber 400 frequently contacts and rubs against the road surface 500. These evenly dispersed iron powders can form a conductive network in the rubber, effectively reducing static electricity accumulation and reducing safety hazards caused by static electricity discharge. At the same time, the good conductivity of iron powder can also promote charge transmission, solve the problem of insensitive signal transmission of sensors in tires, and further improve the safety and functionality of tires during use.

[0028] It should be noted that the sidewall rubber 300 is composed of the following components by weight: 100 parts of rubber matrix; 35-40 parts of carbon black; 4-5 parts of activator; 2.5-3 parts of vulcanizer; 1-3 parts of iron powder; 100 parts of rubber matrix provides the core elasticity and flexibility for the entire sidewall rubber composition. A sufficient amount of rubber matrix ensures that the tire can effectively buffer vibrations under various road conditions and improve driving comfort. At a ratio of 35-40 parts, carbon black can fully combine with the rubber matrix to enhance the strength and fatigue resistance of the sidewall. 2.5-3 parts of vulcanizer and 4-5 parts of activator work synergistically. The activator can reduce the activation energy of the reaction, accelerate the vulcanization speed, shorten the production cycle, and improve production efficiency.

[0029] Adding 1 to 3 parts of iron powder to the sidewall rubber 300 can eliminate the hidden danger of static electricity: when the vehicle is driving, the friction between the sidewall and the ground and the surrounding air is likely to generate static electricity. The accumulated static electricity may not only interfere with the normal operation of electronic equipment in the car, but also pose safety risks such as fire. The addition of iron powder can form a conductive path to promptly conduct the generated static electricity, reduce static electricity accumulation, and avoid safety problems caused by static electricity discharge. In addition, it can optimize the signal transmission environment of the sensor, improve the signal transmission quality, and enable the sensor data to be transmitted to the vehicle control system more timely and accurately.

[0030] It should be noted that the transition layer rubber is composed of the following components by weight: 100 parts of rubber matrix; 50-55 parts of carbon black; 5-8 parts of activator; 4-6 parts of vulcanizer; 4-8 parts of iron powder. The addition of 5-8 parts of activator and 4-6 parts of vulcanizer can reduce the required vulcanization temperature during the vulcanization process, which not only saves energy, but also reduces the adverse effects of high temperature on the rubber matrix and other additives, which is conducive to maintaining the original performance of the rubber.

[0031] However, adding 4 - 8 parts of iron powder to the transition layer rubber of the tire also has outstanding advantages in conductivity. During the vehicle's driving process, the transition layer rubber will generate static electricity due to various stresses and frictions. The addition of iron powder can build a conductive path within the transition layer rubber to quickly conduct the generated static electricity out, avoiding static electricity accumulation. In addition, good conductivity can also assist the sensor signal to be transmitted more smoothly between the tire layers, improving the accuracy of the sensor's monitoring of the tire state and providing more reliable data support for the safe driving of the vehicle.

[0032] In the embodiments of the present invention, the rubber matrix includes one or more of natural rubber, cis - butadiene rubber, or bromobutyl rubber. For example, it can be natural rubber, or cis - butadiene or bromobutyl rubber, or a mixture of the above.

[0033] In the embodiments of the present invention, the activator is composed of zinc oxide and stearic acid in a mass ratio of 2.5 - 7:1 - 3. For example, 3 parts of zinc oxide and 1 part of stearic acid.

[0034] In the embodiments of the present invention, the accelerator and sulfur are composed in a mass ratio of 0.6 - 1.2:1 - 5.4. For example, 1.2 parts of accelerator and 3.8 parts of sulfur.

[0035] In the embodiments of the present invention, the accelerator includes at least one of sulfenamides, thiazoles, thiurams, thioureas, dithiocarbamates, aldehyde - amines, guanidines, or xanthates. For example, it can be dithiocarbamates, or thiazoles, or a mixture of the above.

[0036] In the embodiments of the present invention, the particle size D50 of the iron powder is 0.1μm - 2μm. The iron powder particle size D50 is the reason for determining the conductive performance of the rubber compounds in each part of the tire: the core difference in iron powder with different particle sizes lies in the "contact point density" and the "continuity of the conductive network": for iron powder with a particle size of 0.1 - 1μm, through a high specific surface area and uniform dispersion, the volume resistivity of the crown rubber, sidewall rubber, and transition layer rubber is reduced by 20% - 30%, 15% - 25%, and 25% - 35% respectively; while when the median particle size of the iron powder is greater than 1μm, the dispersibility deteriorates, and the improvement amplitude of the conductive performance gradually attenuates with the increase in particle size. When the median particle size of the iron powder exceeds 2μm, the conductive network almost breaks, and the resistivity approaches the level without addition.

[0037] In addition, the preparation method of the components of the crown rubber, sidewall rubber, and transition layer rubber in the present invention is to add the basic rubber under pressure using a mixer or an open mill, and then add each component in sequence for mixing and stirring.

[0038] Example 1

[0039] Example 1 provides a crown rubber composition, which is composed of the following components by weight: 100 parts of rubber matrix; 50 parts of carbon black; 6 parts of activator (3 parts of zinc oxide and 3 parts of stearic acid); 2.2 parts of vulcanizing agent (1.2 parts of accelerator and 1 part of sulfur); 4 parts of iron powder with a particle size of 1 μm and D50.

[0040] Its preparation method is the same as the preparation method mentioned above.

[0041] Example 2

[0042] Example 2 provides a crown rubber composition, which is composed of the following components by weight: 100 parts of rubber matrix; 48 parts of carbon black; 6 parts of activator (3 parts of zinc oxide and 3 parts of stearic acid); 2.5 parts of vulcanizing agent (1.2 parts of accelerator and 1.3 parts of sulfur); 4 parts of iron powder with a particle size of 1 μm and D50.

[0043] Example 3

[0044] Example 3 provides a crown rubber composition, which is composed of the following components by weight: 100 parts of rubber matrix; 50 parts of carbon black; 5.5 parts of activator (3 parts of zinc oxide and 2.5 parts of stearic acid); 2.5 parts of vulcanizing agent (1 part of accelerator and 1.5 parts of sulfur); 8 parts of iron powder with a particle size of 1 μm and D50.

[0045] Comparative Example 1

[0046] Comparative Example 1 provides a crown rubber composition, whose preparation method is the same as the parameter steps of Example 1, and the difference is that iron powder is not added in the components.

[0047] Example 4

[0048] Example 4 provides a sidewall rubber composition, which is composed of the following components by weight: 100 parts of rubber matrix (60 parts of natural rubber and 40 parts of cis-butadiene rubber); 35 parts of carbon black; 5 parts of activator (3.5 parts of zinc oxide and 1.5 parts of stearic acid); 3 parts of vulcanizing agent (1.2 parts of accelerator and 1.8 parts of sulfur); 1 part of iron powder with a particle size of 0.5 μm and D50.

[0049] Example 5

[0050] Example 5 provides a sidewall rubber composition, which is composed of the following components by weight: 100 parts of rubber matrix (50 parts of natural rubber and 50 parts of cis-butadiene rubber); 38 parts of carbon black; 5 parts of activator (3 parts of zinc oxide and 2 parts of stearic acid); 2.8 parts of vulcanizing agent (1 part of accelerator and 1.8 parts of sulfur); 2 parts of iron powder with a particle size of 0.5 μm and D50.

[0051] Example 6

[0052] This embodiment 6 provides a sidewall rubber composition, which is composed of the following components in parts by weight: 100 parts of rubber matrix (50 parts of natural rubber and 50 parts of butadiene rubber); 40 parts of carbon black; 5 parts of activator (4 parts of zinc oxide and 1 part of stearic acid); 2.5 parts of vulcanizer (1 part of accelerator and 1.5 parts of sulfur); 3 parts of iron powder with a particle size D50 of 0.5μm.

[0053] Comparative Example 2

[0054] Comparative Example 2 provides a sidewall rubber composition, and its preparation method has the same parameters and steps as Example 4, except that no iron powder is added to the composition.

[0055] Example 7

[0056] This embodiment 7 provides a transition layer rubber composition, which is composed of the following components in parts by weight: 100 parts of rubber matrix; 50 parts of carbon black; 8 parts of activator (7 parts of zinc oxide and 1 part of stearic acid); 6 parts of vulcanizer (0.75 parts of accelerator and 5.25 parts of sulfur); 4 parts of iron powder with a particle size D50 of 1 μm.

[0057] Example 8

[0058] This embodiment 8 provides a transition layer rubber composition, which is composed of the following components in parts by weight: 100 parts of rubber matrix; 55 parts of carbon black; 6 parts of activator (5 parts of zinc oxide and 1 part of stearic acid); 4 parts of vulcanizer (1 part of accelerator and 3 parts of sulfur); 6 parts of iron powder with a particle size D50 of 1 μm.

[0059] Example 9

[0060] This embodiment 9 provides a transition layer rubber composition, which is composed of the following components in parts by weight: 100 parts of rubber matrix; 50 parts of carbon black; 6 parts of activator (5 parts of zinc oxide and 1 part of stearic acid); 5.5 parts of vulcanizer (0.75 parts of accelerator and 4.75 parts of sulfur); 8 parts of iron powder with a particle size D50 of 1 μm.

[0061] Comparative Example 3

[0062] Comparative Example 3 provides a transition layer rubber composition, and its preparation method has the same parameters and steps as Example 7, except that no iron powder is added to the composition.

[0063] The volume resistivity of the rubbers obtained in Examples 1 to 9 was compared with that of Comparative Examples 1 to 3. The results are shown in Table 1.

[0064]

[0065] Table 1

[0066] As can be seen from the data in Table 1, first, Examples 1-9 are used to prepare rubber for various parts of the tire, but iron powder is not added to the components in Comparative Examples 1-3; in Examples 1-9, the particle size D50 of iron powder is adjusted according to actual needs. The particle size D50 of iron powder is the particle size when the cumulative distribution of iron powder particles reaches 50%, also known as the median diameter or median particle size, representing the average particle size of iron powder.

[0067] In addition, since the crown rubber of the tire is in direct contact with the road surface, from the data, its conductivity is significantly improved and the resistance value is relatively low after adding iron powder, indicating that the crown rubber has relatively high requirements for conductivity to quickly conduct away the static electricity generated by friction with the road surface. The sidewall rubber and the transition layer rubber do not directly contact the road surface, and the requirements for conductivity are relatively lower than those of the crown rubber. That is, the closer to the road surface, due to direct contact with the road surface, problems such as static electricity generated by friction are prominent, and the requirements for conductivity are the highest; the sidewall rubber and the transition layer rubber do not directly contact the road surface, and relatively speaking, the requirements for conductivity decrease in turn.

[0068] Moreover, the lower the volume resistivity, the smaller the resistance and the higher the conductivity. From the conductivity data of the crown rubber, sidewall rubber and transition layer of the tire after adding different amounts of iron powder, it can be seen that the resistance value of the crown rubber decreases significantly and the conductivity is significantly improved after adding iron powder; the conductivity of the sidewall rubber and the transition layer rubber also improves, but compared with the crown rubber, the improvement amplitude is relatively small.

[0069] Finally, it should be noted that: the above specific embodiments have further elaborated on the purpose, technical solutions and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A tire for improving electrical conductivity, comprising a crown rubber, a sidewall rubber, and a transition layer rubber, characterized in that the crown rubber, the sidewall rubber, and the transition layer rubber all comprise the following components: a rubber matrix, carbon black, an activator, a vulcanizing agent, and iron powder.

2. The tire for improving electrical conductivity according to claim 1, characterized in that the crown rubber, by weight, consists of the following components: 100 parts of rubber matrix; 45 - 50 parts of carbon black; 5.5 - 6 parts of activator; 2.2 - 2.5 parts of vulcanizing agent; 4 - 8 parts of iron powder.

3. The tire for improving electrical conductivity according to claim 2, characterized in that the sidewall rubber, by weight, consists of the following components: 100 parts of rubber matrix; 35 - 40 parts of carbon black; 4 - 5 parts of activator; 2.5 - 3 parts of vulcanizing agent; 1 - 3 parts of iron powder.

4. The tire for improving electrical conductivity according to claim 3, characterized in that the transition layer rubber, by weight, consists of the following components: 100 parts of rubber matrix; 50 - 55 parts of carbon black; 5 - 8 parts of activator; 4 - 6 parts of vulcanizing agent; 4 - 8 parts of iron powder.

5. The tire for improving electrical conductivity according to claim 4, characterized in that the rubber matrix comprises at least one of natural rubber, cis - 1,4 - polybutadiene rubber, or bromobutyl rubber.

6. The tire for improving electrical conductivity according to claim 5, characterized in that the activator is composed of zinc oxide and stearic acid in a mass ratio of 2.5 - 7:1 - 3.

7. The tire for improving electrical conductivity according to claim 6, characterized in that the vulcanizing agent is composed of an accelerator and sulfur in a mass ratio of 0.6 - 1.2:1 - 5.

4.

8. The tire for improving electrical conductivity according to claim 7, characterized in that the accelerator comprises at least one of sulfenamides, thiazoles, thiurams, thioureas, dithiocarbamates, aldehyde - amines, guanidines, or xanthates.

9. The tire for improving electrical conductivity according to claim 8, characterized in that the particle size D50 of the iron powder is 0.1 μm - 2 μm.

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