Multi-component carbon / carbon composite materials and their preparation methods

Abstract

This invention discloses a multi-component carbon / carbon composite material for preparing tire tread rubber, comprising graphene oxide, graphene, carbon nanotubes, carbon black, and ultrafine carbon black powder, wherein the mass ratio of graphene, graphene oxide, carbon nanotubes, and carbon black is 1:0.5 to 1:0.5 to 1:0.1 to 5. The invention also discloses a method for preparing this composite material, which is prepared by granulation of a dispersion containing the aforementioned graphene oxide, graphene, carbon nanotubes, and carbon black with carbon black powder. Conventional surfactant-type dispersants are not used in the preparation process. This improves the dispersion of graphene materials in rubber, fully utilizes the reinforcing effect of graphene on rubber, and yields a high-performance tire tread rubber with outstanding mechanical properties, low heat generation, and high wear resistance.

Description

Technical Field

[0001] This invention belongs to the field of composite material preparation, specifically relating to a high-performance multi-component carbon / carbon composite material for tire tread rubber and its preparation method. Background Technology

[0002] The tread is a crucial component of a tire, directly contacting the ground and serving to bear the load, protect the tire body, and experience the most wear and tear during tire use, thus determining the tire's lifespan. Therefore, developing a high-performance tire tread compound with outstanding mechanical properties, low heat generation, and high wear resistance could effectively extend tire lifespan, mitigate performance degradation caused by thermal aging, and reduce environmental pollution from tire wear debris, making it of significant practical importance.

[0003] Graphene possesses a large specific surface area and excellent mechanical, thermal, and electrical properties, making it promising for applications in improving the mechanical properties of tire treads, reducing compression heat, and enhancing wear resistance. However, due to the unique structure of graphene, strong π-π conjugated interactions and van der Waals forces exist between its sheets. Adding it alone in powder form can lead to severe agglomeration, hindering the improvement of rubber performance and even creating stress concentration points that damage the original properties of the rubber. Furthermore, the lack of functional groups on the graphene surface prevents it from interacting with rubber molecular chains, resulting in weak interfacial bonding between the filler and the matrix, further limiting the reinforcing effect of graphene.

[0004] Chinese patent 201810897139.9 discloses a method for preparing a graphene-based automotive tire tread compound. First, a graphene dispersion is mixed with styrene-butadiene rubber latex, and flocculation is performed to obtain a graphene / styrene-butadiene rubber composite material. Then, the graphene / styrene-butadiene rubber composite material is mechanically blended with butadiene rubber, various fillers, and compounding agents to obtain a high-performance automotive tire tread compound with high wear resistance and low rolling resistance. While this method ensures uniform dispersion of graphene, it is only applicable to redox graphene. Furthermore, the graphene / styrene-butadiene rubber composite material requires a large amount of graphene, and the preparation process is complex, which is not conducive to industrial production.

[0005] Chinese patent 201811147399.0 discloses a method for preparing multiphase nanoscale composite carbon materials. This method utilizes an in-situ grafting reaction between graphene, carbon black, and a coupling agent to increase the porosity between carbon black particles. The graphene and coupling agent are then interspersed within the carbon black particles, resulting in a microparticle-like multiphase nanoscale composite carbon material where graphene and carbon black particles are isolated from each other. This material is added to semi-steel and full-tire tread compound formulations to produce tread compounds with high wear resistance, low heat generation, and good electrical conductivity. While this method effectively disperses graphene, it requires a large amount of surfactant to prepare the graphene powder, leading to unnecessary resource waste. Furthermore, the grafting reaction time for some coupling agents is relatively long, making it more suitable for small-scale laboratory preparations and limiting its application in large-scale production. Summary of the Invention

[0006] To address the aforementioned technical deficiencies, this invention provides a high-performance multi-component carbon / carbon composite material for tire tread rubber and its preparation method. The aim is to improve the dispersion of graphene materials in rubber during industrial production, fully utilize the reinforcing effect of graphene on rubber, and obtain a high-performance tire tread rubber with outstanding mechanical properties, low heat generation, and high wear resistance.

[0007] This invention provides a multi-component carbon / carbon composite material for preparing tire tread rubber, comprising graphene oxide, graphene, carbon nanotubes, carbon black, and filled carbon black ultrafine powder; wherein the graphene is one or more of physical graphene, supercritical graphene, and redox graphene, preferably physical graphene; the carbon black is one or more of the N600, N500, N700, and N900 series, preferably N990; the filled carbon black ultrafine powder is obtained by pulverizing rubber-grade carbon black particles, wherein the rubber-grade carbon black particles are one or more of the N200, N300, and N100 series, preferably N330.

[0008] The particle size of the carbon black ultrafine powder is 200 mesh or larger.

[0009] According to one embodiment of the present invention, the graphene oxide is graphene oxide with an oxygen content of not less than 10%, preferably graphene oxide with an oxygen content of about 30%.

[0010] The graphene has a particle size D90 of 4–35 μm, preferably about 4 μm;

[0011] The carbon nanotubes are single-walled carbon nanotubes; the diameter is 1-6 nm, preferably about 3 nm; the aspect ratio is 5000-8000, preferably about 6000; the mass ratio of graphene to carbon nanotubes is 1:0.1-10.

[0012] According to one embodiment of the present invention, the mass ratio of graphene, graphene oxide, carbon nanotubes and carbon black is 1:0.5 to 1:0.5 to 1:0.1 to 5; preferably, the mass ratio of graphene, graphene oxide, carbon nanotubes and carbon black is 1:0.5:1:1.

[0013] Another aspect of the present invention provides a method for preparing the above-mentioned composite material, wherein the composite material is prepared by granulation of a dispersion containing the graphene oxide, graphene, carbon nanotubes and carbon black and filled carbon black.

[0014] According to one embodiment of the present invention, the above preparation method specifically includes:

[0015] S1: Add graphene oxide to deionized water and disperse it to obtain a uniform graphene oxide dispersion.

[0016] S2: Add graphene to the S1 dispersion to obtain a uniform graphene dispersion of graphene oxide.

[0017] S3: Add carbon nanotubes to the S2 dispersion to obtain a uniform dispersion of carbon nanotube / graphene binary carbon / carbon composite material.

[0018] S4: Add carbon black to the S3 dispersion to obtain a uniform dispersion of graphene / carbon nanotube / carbon black ternary carbon / carbon composite material.

[0019] S5: Atomize the S4 dispersion into extremely small droplets, and then granulate it with fluidized filled carbon black ultrafine powder to obtain a multi-element carbon / carbon composite material.

[0020] According to one embodiment of the present invention, the concentration of graphene in the S2 dispersion is 0.5 to 50 mg / mL, preferably 10 mg / mL.

[0021] According to one embodiment of the present invention, the dispersion method includes one or more of high-speed stirring, high-speed shear emulsification, ultrasound, ball milling, and homogenization; wherein the high-speed stirring speed is 1000 rpm; the shear rate of the high-speed shear emulsification is 18000 rpm; the ultrasound power is 1600 W and the ultrasound frequency is 20 kHz; the ball milling speed is 480 rpm and the ball-to-material ratio is 5:1; the homogenization pressure is 1000 bar; the temperature is maintained below 50°C during both the ultrasound and homogenization processes; preferably, the ultrasound temperature is 15°C and the homogenization temperature is 10°C; preferably, the dispersion method in S1 is high-speed stirring followed by ultrasound; the dispersion methods in S2, S3, and S4 are high-speed stirring followed by high-speed shear emulsification and finally homogenization.

[0022] According to one embodiment of the present invention, the specific process of composite granulation in step S5 is as follows:

[0023] 1) The carbon black ultrafine powder is added to the bottom screen of the granulation chamber and hot air is introduced to make it circulate in the granulator in a "boiling state" under the action of hot air.

[0024] 2) The dispersion of the graphene / carbon nanotube / carbon black ternary carbon / carbon composite material obtained via S4 is centrifuged and atomized by a peristaltic pump to a high-speed centrifugal atomizer at the top, where it comes into uniform contact with the fluidized carbon black ultrafine powder and aggregates into particles. Using a high-speed centrifugal atomizer instead of a traditional high-pressure spray atomizer solves the problem of easy clogging of high-pressure nozzles, improves the uniformity of atomized droplets, and results in well-developed, uniformly sized, and easily dispersed ternary carbon / carbon composite material particles.

[0025] 3) A hot airflow is continuously introduced to rapidly dry the granulated product, resulting in multi-element carbon / carbon composite material particles.

[0026] According to one embodiment of the present invention, the mass ratio of the filled carbon black ultrafine powder to the graphene in the dispersion is 20 to 40:1, preferably 30:1.

[0027] According to one embodiment of the present invention, the viscosity of the dispersion of the ternary carbon / carbon composite material is 500-2000 Pa·s, preferably 1000 Pa·s; the flow rate of the peristaltic pump is 15-30 L / h; the rotation speed of the high-speed centrifugal atomizer is 20000-30000 r / min; the hot air inlet temperature is 100-180℃; the outlet temperature is 20-60℃; and the granulation time is 5-60 min. Preferably, the flow rate of the peristaltic pump is 25 L / h; the rotation speed of the high-speed centrifugal atomizer is 25000 r / min; the hot air inlet temperature is 140℃; the outlet temperature is 30℃; and the granulation time is 30 min.

[0028] Another aspect of the present invention provides an application of the above-mentioned composite material in the preparation of tire tread compound.

[0029] Beneficial effects:

[0030] 1. Conventional surfactant-type dispersants were not used in the preparation of the multi-component carbon / carbon composite material, thus eliminating the negative impact of dispersants on the reinforcing effect;

[0031] 2. The composite granulation of ternary carbon / carbon composite material with filled carbon black powder reduces dust pollution and improves the industrial production environment;

[0032] 3. The multi-component carbon / carbon composite material ensures the uniform dispersion of graphene in rubber. The preparation process is simple, it can be prepared on a large scale, and it has the potential for industrial production.

[0033] 4. Replacing traditional surfactant dispersants with graphene oxide not only ensures the uniform dispersion of graphene in aqueous solvents, but also compensates for the weak interaction between graphene and rubber molecules, enhances the interfacial bonding between fillers and the matrix, and improves the wear resistance of rubber composites.

[0034] 5. The low-part multi-element carbon / carbon composite material of the present invention can replace multiple parts of carbon black, reducing the amount of filler in the rubber composite material, improving mechanical properties while reducing friction between filler particles, and effectively reducing the compression heat of the tire. Attached Figure Description

[0035] Figure 1 This is a SEM image of a graphene / carbon nanotube binary carbon / carbon composite material.

[0036] Figure 2 This is a SEM image of a graphene / carbon nanotube / carbon black ternary carbon / carbon composite material.

[0037] Figure 3 It is a multi-component carbon / carbon composite material particle.

[0038] Figure 4 This is a schematic diagram of the assembly of a multi-component carbon / carbon composite material. Detailed Implementation

[0039] The present invention will be further described in detail below with reference to specific examples. Unless otherwise specified, the methods described are conventional methods. The following embodiments are used to illustrate the present invention, but should not be regarded as limiting the scope of the present invention.

[0040] One objective of this invention is to provide a high-performance multi-component carbon / carbon composite material for tire tread rubber and its preparation method. The specific technical solution is as follows:

[0041] S1: Add graphene oxide to deionized water and disperse it to obtain a uniform graphene oxide dispersion.

[0042] S2: Add graphene to the S1 dispersion to obtain a uniform graphene dispersion of graphene oxide.

[0043] S3: Add carbon nanotubes to the S2 dispersion to obtain a uniform dispersion of carbon nanotube / graphene binary carbon / carbon composite material.

[0044] S4: Add carbon black to the S3 dispersion to obtain a uniform dispersion of graphene / carbon nanotube / carbon black ternary carbon / carbon composite material.

[0045] S5: Atomize the S4 dispersion into extremely small droplets, and then granulate it with fluidized filled carbon black ultrafine powder to obtain a multi-element carbon / carbon composite material.

[0046] In this invention, the dispersion method described in the above steps includes at least one of high-speed stirring, high-speed shear emulsification, ultrasonication, ball milling, and homogenization.

[0047] Preferably, the high-speed stirring speed is 1000 rpm; the high-speed shear emulsification shear rate is 18000 rpm; the ultrasonic power is 1600 W and the ultrasonic frequency is 20 kHz; the ball milling speed is 480 rpm and the ball-to-material ratio is 5:1; and the homogenization pressure is 1000 bar.

[0048] Further optimization involves the following dispersion methods: in S1, high-speed stirring followed by ultrasonication; in S2, S3, and S4, high-speed stirring followed by high-speed shear emulsification followed by homogenization.

[0049] In this invention, in order to ensure the dispersibility of graphene oxide, graphene, carbon nanotubes and carbon black, the temperature is kept at 50°C or below during the ultrasonication and homogenization processes described in the above steps.

[0050] Preferably, the ultrasonic temperature is 15℃ and the homogenization temperature is 10℃.

[0051] In this invention, to avoid the negative impact of introducing surfactants on subsequent mixing processes and rubber reinforcement, the dual properties of graphene oxide—its ability to be stably dispersed in water (due to its abundant oxygen-containing functional groups on its surface) and its affinity for graphene sheets (due to the π-π conjugated interaction between the benzene rings on the graphene oxide substrate and the benzene rings on the graphene sheet)—are utilized to achieve stable dispersion of graphene in an aqueous solvent. To achieve the above effects, this invention employs a process of first obtaining a graphene oxide dispersion, and then adding graphene to the graphene oxide dispersion for further dispersion.

[0052] In this invention, the graphene oxide is graphene oxide with an oxygen content of not less than 10%.

[0053] Preferably, the oxygen content of graphene oxide is about 30%. When the oxygen content is low, the monolayer ratio in the dispersion is too low, and the dispersing effect of graphene oxide cannot be fully utilized. When the oxygen content increases, it means that the number of sp2 hybridized carbon atoms remaining on the sheets decreases, which reduces the attraction to graphene and also affects the dispersion effect.

[0054] In this invention, the graphene described in S2 is one or more of the following: physical graphene, supercritical graphene, redox graphene, or graphene obtained by other preparation methods. The graphene content in the dispersion is 0.5–50 mg / mL, and the graphene particle size is D90 = 4–35 μm.

[0055] Preferably, the graphene in S2 is physically produced graphene, the graphene content in the dispersion is 10 mg / mL, and the graphene particle size is D90 = 4 μm.

[0056] In this invention, carbon nanotubes can be combined with graphene through π-π conjugation interaction to isolate graphene. However, since carbon nanotubes are not easy to disperse in water, this invention chooses to introduce carbon nanotubes after obtaining a stable and uniform graphene dispersion, so that they are uniformly attached to the graphene surface, thus preventing the overlapping of graphene sheets in the powder state.

[0057] In this invention, the carbon nanotubes described in S3 are single-walled carbon nanotubes with a diameter of 1–6 nm and an aspect ratio of 5000–8000. The mass ratio of graphene to carbon nanotubes is 1:0.1–10. This is because the small diameter of single-walled carbon nanotubes makes them easier to intercalate between graphene sheets, which is beneficial for further dispersion of graphene. Furthermore, the high aspect ratio and unique flexibility of single-walled carbon nanotubes offer advantages in forming cross-linked meshes.

[0058] Preferably, the tube diameter is 3 nm, the aspect ratio is 6000, and the mass ratio of graphene to carbon nanotubes is 1:1.

[0059] In this invention, carbon nanotubes are uniformly attached to the graphene surface, transforming the strong bonding between graphene sheets into weak bonding between carbon nanotube lines. Considering a more superior point-to-point bonding mechanism, carbon black particles are further introduced. To achieve the above effects, the carbon nanotubes are added before the carbon black. This is because the graphene used in this invention does not require a high number of layers; some graphene layers have a high number of layers, and their smooth surface is not conducive to the adsorption of carbon black particles. In this case, the carbon nanotubes added first composite on the graphene surface and form a mesh structure, which is beneficial for the adsorption and fixation of the subsequently added carbon black particles.

[0060] In this invention, the carbon black described in S4 is mainly used to further isolate and disperse graphene. Therefore, inexpensive carbon black with small particle size and low structure can be selected, including at least one of the N600, N500, N700 and N900 series. The mass ratio of graphene, graphene oxide, carbon nanotubes and carbon black described in S4 is 1:0.5 to 1:0.5 to 1:0.1 to 5.

[0061] As a preferred option, the carbon black in S4 is N990, and the mass ratio of graphene, graphene oxide, carbon nanotubes, and carbon black is 1:0.5:1:1.

[0062] In this invention, instead of simply physically mixing ternary carbon / carbon composite materials with filler carbon black, the filler carbon black and ternary carbon / carbon composite materials are further compounded and granulated to obtain a multi-component carbon / carbon composite material. This multi-component carbon / carbon composite material is then used to completely replace the filler carbon black in the tread rubber, reducing the dynamic friction between filler carbon black particles and effectively reducing the compression heat generated by the tread rubber.

[0063] In this invention, a small amount of carbon black particles are first compounded with graphene-carbon nanotube carbon / carbon composite material, and then compounded with a large amount of carbon black ultrafine powder for granulation. This effectively avoids the problem of uneven graphene dispersion caused by direct compounding of graphene-carbon nanotube carbon / carbon composite material with a large amount of carbon black. In addition, the mutual attraction between carbon black particles can eliminate the introduction of binders in the subsequent granulation process.

[0064] In this invention, the ultrafine carbon black powder described in S5 is obtained by crushing carbon black particles for rubber, including at least one of the N200, N300, and N100 series.

[0065] Preferably, the carbon black ultrafine powder is obtained by grinding with N330, and no binder is added during the composite granulation process. This is because there is a mutual attraction between the graphene / carbon nanotube / carbon black ternary carbon / carbon composite material and the carbon black ultrafine powder, and the carbon black powder contains a small amount of binder, which is sufficient for the ternary carbon / carbon composite material to form particles with the carbon black powder.

[0066] In this invention, fluidized bed granulation process is used in step S5 to achieve composite granulation of ternary carbon / carbon composite material and filled carbon black. The specific process is as follows:

[0067] 1) Add the carbon black ultrafine powder to the bottom screen of the granulation chamber and pass in hot air to make it circulate in the granulator in a "boiling state" under the action of the hot air.

[0068] 2) The dispersion of graphene / carbon nanotube / carbon black ternary carbon / carbon composite material is pumped to the top high-speed centrifugal atomizer by peristaltic pump for centrifugal atomization, and then uniformly contacts the fluidized carbon black ultrafine powder to aggregate into particles.

[0069] 3) A hot airflow is continuously introduced to rapidly dry the granulated product, resulting in multi-element carbon / carbon composite material particles.

[0070] In this invention, since the carbon black / carbon nanotube / graphene ternary composite material dispersion is prone to clogging the traditional high-pressure atomizing nozzle of the fluidized bed granulator, and the atomized droplet size is uniformly low, a high-speed centrifugal atomizer is used to atomize the dispersion.

[0071] In this invention, since the viscosity of the dispersion is a key factor affecting the granulation effect, if the viscosity is too high, the particles will easily become hard, and if the viscosity is too low, the particles will be too weak to form granules. Therefore, in the granulation process of this invention, the viscosity of the dispersion is 500-2000 Pa·s, the mass ratio of the carbon black ultrafine powder to the graphene in the dispersion is 20-40:1, the flow rate of the peristaltic pump is 15-30 L / h, the rotation speed of the high-speed centrifugal atomizer is 20000-30000 r / min, the hot air inlet temperature is 100-180℃, the outlet temperature is 20-60℃, and the granulation time is 5-60 min.

[0072] Preferably, the dispersion viscosity is 1000 Pa·s, the mass ratio of the filled carbon black ultrafine powder to the graphene in the dispersion is 30:1, the flow rate of the peristaltic pump is 25 L / h, the rotation speed of the high-speed centrifugal atomizer is 25000 r / min, the hot air inlet temperature is 140℃, the outlet temperature is 30℃, and the granulation time is 30 min.

[0073] The second objective of this invention is to provide a high-performance tire tread compound with outstanding mechanical properties, low heat generation, and low wear, characterized in that it comprises a multi-element carbon / carbon composite material as described in the first objective of this invention.

[0074] The inventive concept of the present invention will be explained and illustrated below through specific embodiments. Unless otherwise specified, all raw materials used in the embodiments can be obtained from publicly available commercial sources.

[0075] Example 1

[0076] S1: Graphene oxide was dispersed in 250 mL of deionized water, stirred at high speed for 10 min and sonicated for 30 min to obtain a uniformly dispersed graphene oxide dispersion, wherein the graphene oxide content was 5 mg / mL and the oxygen content of the graphene oxide was 30%.

[0077] S2: Add the redox graphene to the above graphene oxide dispersion, stir at high speed for 10 min, sonicate for 30 min, and homogenize for 1 h to obtain a uniformly dispersed graphene dispersion with a graphene content of 10 mg / mL and a dispersion D90 of 6.02 μm.

[0078] S3: Add carbon nanotubes to the graphene dispersion of S2, stir at high speed for 10 min, sonicate for 30 min, and homogenize for 1 h to obtain a uniformly dispersed carbon nanotube-graphene carbon / carbon composite material dispersion, wherein the carbon nanotube content is 10 mg / mL; the carbon nanotubes are single-walled carbon nanotubes with a diameter of (1-2 nm) and an aspect ratio of (6000).

[0079] S4: Add carbon black to the carbon nanotube-graphene dispersion in S3, stir at high speed for 10 min and homogenize for 1 h to obtain a dispersion of carbon black / carbon nanotube / graphene ternary carbon / carbon composite material, wherein the carbon black content is 50 mg / mL; the type of carbon black is (N990).

[0080] S5: Atomize the dispersion in S4 and granulate it with the filled carbon black ultrafine powder to obtain a multi-element carbon / carbon composite material. The filled carbon black ultrafine powder is obtained by crushing (N330).

[0081] The specific granulation process is as follows:

[0082] 1) Add the carbon black ultrafine powder to the screen at the bottom of the granulator, and introduce a hot airflow at a temperature of 140℃ with a flow rate of 9.5m³. 3 The flow rate is 30 m / min, which makes it circulate in a "boiling" state in the granulator. The mass ratio of the carbon black ultrafine powder to the graphene in the dispersion is 30:1, and the exhaust gas temperature is 30°C.

[0083] 2) The dispersion of carbon black / carbon nanotube / graphene ternary carbon / carbon composite material is sent to the high-speed centrifugal atomizer at the top of the granulator by a peristaltic pump at a rate of 25 L / h. The atomization speed is 25000 r / min and the viscosity of the dispersion is (1000 Pa·s).

[0084] 3) The atomized droplets come into uniform contact with the fluidized carbon black ultrafine powder, forming aggregated particles.

[0085] 4) Continuously introduce hot air and granulate and dry for 30 minutes to obtain multi-element carbon / carbon composite material particles with good particle size.

[0086] Example 2

[0087] The operation is the same as in Example 1, except that the redox graphene in S2 is replaced with physical graphene, and the dispersion D90 in S2 is 4.84 μm.

[0088] Example 3

[0089] The operation is the same as in Example 1, except that the redox graphene in S2 is replaced with supercritical graphene, and the dispersion D90 in S2 is 10.90 μm.

[0090] Comparative Example

[0091] Carbon / carbon materials were obtained by simply physically mixing the graphene oxide, graphene, carbon nanotubes, carbon black, and filler carbon black used in Example 2.

[0092] Experimental Example

[0093] With only carbon black added as a reinforcing material, the basic formulation includes the following components by weight: 100 parts natural rubber, 45 parts carbon black, 5 parts zinc oxide, 2 parts stearic acid, 7.5 parts antioxidant RD, 2 parts microcrystalline wax, 1.8 parts sulfur, 1 part accelerator NS, 1.5 parts anti-sulfurization agent PK900, and 0.15 parts anti-scorching agent CTP.

[0094] Preparation method of tread rubber semi-finished product: The rubber compound is first mixed in an internal mixer according to the above formula, then calendered on a two-roll mill, and finally vulcanized in a flat vulcanizing machine to obtain tread rubber semi-finished product.

[0095] Test methods

[0096] Tensile strength: The testing standard was GB / T528-2009, and the equipment used was Instron 3365;

[0097] Tear strength: The testing standard is GB / T528-2009, and the equipment used is Instron 3365;

[0098] Compression heat generation: The testing standard is ASTM D623-07(2014), and the equipment used is Alpha Model II;

[0099] Akron wear: The testing standard is GB / T1689-2014, and the equipment used is the Taiwan High Speed ​​Rail GT-7012-A.

[0100] To verify the reinforcing effect of the multi-component carbon / carbon composite material in the tread compound, the carbon black in the basic formulation (i.e., the formulation with carbon black as the reinforcing agent only) was completely replaced with the multi-component carbon / carbon composite material in the above examples or the carbon / carbon material in the comparative examples. The mass ratio of carbon black to multi-component carbon / carbon composite material or carbon / carbon material was 5:1. After internal mixing, the corresponding tread compound semi-finished products were obtained, and their performance was tested. The results are shown in Table 1.

[0101]

[0102] As shown in Table 1, the performance of the tread compounds in the examples and comparative examples is superior to that of the basic formulation. This indicates that nano-carbon materials such as graphene and carbon nanotubes can effectively enhance the tread compound, especially improving its mechanical properties. Compared with the comparative example, the tread compound prepared by adding the multi-component carbon / carbon composite material of this invention shows significant improvements in mechanical properties, compression heat generation, and abrasion, with Example 2 exhibiting even better overall performance. This demonstrates that compared to physical mixing, the graphene adsorbed by carbon nanotubes and carbon black particles is more uniformly dispersed in the rubber. Simultaneously, the interaction between carbon nanotubes, carbon black, and graphene improves the compression heat generation problem caused by dynamic friction in the tread compound. Furthermore, the graphene oxide contained in the multi-component carbon / carbon composite material enhances the interfacial interaction between the filler and the matrix, reduces tread compound abrasion, and effectively extends its service life.

Claims

1. A multi-component carbon / carbon composite material for preparing tire tread compound, characterized in that, Including graphene oxide, graphene, carbon nanotubes, carbon black, and filled carbon black ultrafine powder; The graphene is one or more of the following: physical graphene, supercritical graphene, and redox graphene. The carbon black is one or more of the N600, N500, N700, and N900 series; The filled carbon black ultrafine powder is obtained by crushing rubber-grade carbon black particles, and the rubber-grade carbon black particles are one or more of the N200, N300, and N100 series. The graphene oxide is graphene oxide with an oxygen content of 10% to 30%. The mass ratio of graphene, graphene oxide, carbon nanotubes, and carbon black is 1:0.5~1:0.5~1:0.1~5. The preparation method of the composite material specifically includes the following steps: S1: The graphene oxide is added to deionized water and dispersed to obtain a uniform graphene oxide dispersion. S2: The graphene is added to the dispersion in S1 and dispersed to obtain a uniform graphene dispersion of graphene oxide. S3: The carbon nanotubes are added to the dispersion in S2 to obtain a uniform dispersion of carbon nanotube / graphene binary carbon / carbon composite material. S4: Add the carbon black to the dispersion in S3 to obtain a uniform dispersion of graphene / carbon nanotube / carbon black ternary carbon / carbon composite material. S5: Atomize the S4 dispersion into extremely small droplets, and then granulate it with fluidized filled carbon black ultrafine powder to obtain a multi-element carbon / carbon composite material; the mass ratio of the filled carbon black ultrafine powder to the graphene in the S4 dispersion is 20~40:

1.

2. The composite material according to claim 1, characterized in that, The particle size D90 of the graphene is 4~35 μm; The carbon nanotubes mentioned are single-walled carbon nanotubes with a diameter of 1~6 nm and an aspect ratio of 5000~8000.

3. The composite material according to claim 2, characterized in that, The graphene has a particle size D90 of 4 μm; The single-walled carbon nanotubes have a diameter of 3 nm and an aspect ratio of 6000.

4. The composite material according to claim 1, characterized in that, The mass ratio of graphene, graphene oxide, carbon nanotubes, and carbon black is 1:0.5:1:

1.

5. A method for preparing the composite material according to any one of claims 1-4, characterized in that, Specifically, the following steps are included: S1: The graphene oxide is added to deionized water and dispersed to obtain a uniform graphene oxide dispersion. S2: The graphene is added to the dispersion in S1 and dispersed to obtain a uniform graphene dispersion of graphene oxide. S3: The carbon nanotubes are added to the dispersion in S2 to obtain a uniform dispersion of carbon nanotube / graphene binary carbon / carbon composite material. S4: Add the carbon black to the dispersion in S3 to obtain a uniform dispersion of graphene / carbon nanotube / carbon black ternary carbon / carbon composite material. S5: Atomize the S4 dispersion into extremely small droplets, and then granulate it with fluidized filled carbon black ultrafine powder to obtain a multi-element carbon / carbon composite material.

6. The preparation method according to claim 5, characterized in that, The concentration of graphene in the S2 dispersion is 0.5~50 mg / mL.

7. The preparation method according to claim 6, characterized in that, The concentration of graphene in the S2 dispersion is 10 mg / mL.

8. The preparation method according to claim 5, characterized in that, The dispersion methods described in S1 to S4 include one or more of the following: high-speed stirring, high-speed shear emulsification, ultrasound, ball milling, and homogenization; wherein the high-speed stirring speed is 1000 rpm; the shear rate of the high-speed shear emulsification is 18000 rpm; the ultrasound power is 1600 W and the ultrasound frequency is 20 kHz; the ball milling speed is 480 rpm and the ball-to-material ratio is 5:1; the homogenization pressure is 1000 bar; and the temperature is maintained below 50°C during both the ultrasound and homogenization processes.

9. The preparation method according to claim 8, characterized in that, During the ultrasound and homogenization processes, the ultrasound temperature is 15°C and the homogenization temperature is 10°C.

10. The preparation method according to claim 8, characterized in that, The dispersion method in S1 is high-speed stirring followed by ultrasonication; the dispersion methods in S2, S3, and S4 are high-speed stirring followed by high-speed shear emulsification, and finally homogenization.

11. The preparation method according to claim 5, characterized in that, In step S5, the specific process of composite granulation is as follows: 1) The carbon black ultrafine powder is added to the bottom screen of the granulation chamber and hot air is introduced to make it circulate in a "boiling state" under the action of hot air. 2) The dispersion of the graphene / carbon nanotube / carbon black ternary carbon / carbon composite material obtained via S4 is centrifuged and atomized by a peristaltic pump to a high-speed centrifugal atomizer at the top, and is uniformly contacted with the fluidized carbon black ultrafine powder, and aggregated into particles. 3) A hot airflow is continuously introduced to rapidly dry the granulated product, resulting in multi-element carbon / carbon composite material particles.

12. The preparation method according to claim 5, characterized in that, The mass ratio of the filled carbon black ultrafine powder to the graphene in the S4 dispersion is 30:

1.

13. The application of the composite material according to any one of claims 1-4 or the composite material prepared by any one of claims 5-12 in the preparation of tire tread compound.

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