Zinc-magnesium-aluminum ternary nano composite material as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of tire rubber materials, and particularly discloses a zinc-magnesium-aluminum ternary nano composite material as well as a preparation method and application thereof. The chemical composition of the material is ZnxMgyAlzO, x is more than or equal to 0.5 and less than or equal to 0.9, y is more than or equal to 0.04 and less than or equal to 0.4, z is more than or equal to 0.04 and less than or equal to 0.2, and x + y + (3 / 2) z is equal to 1; the BET specific surface area is 40-150 m / g, and the porosity is larger than or equal to 0.15 cm / g. The preparation method comprises the following steps: preparing a mixed salt solution containing a template agent and a dispersing agent, carrying out co-precipitation on the mixed salt solution and an alkaline precipitator under high-speed shearing, washing, carrying out spray drying, and carrying out segmented calcination. According to the present invention, with the application of the material as the additive in the rubber composition, the zinc content in the formula is significantly reduced on the premise of no degradation of the processability and the mechanical property of the rubber material so as to reduce the zinc emission in the tire and the environmental pollution.

Description

Technical Field

[0001] This invention belongs to the field of tire rubber material technology, and in particular relates to a zinc-magnesium-aluminum ternary nanocomposite material, its preparation method and application. Background Technology

[0002] Zinc oxide is a activator in rubber vulcanization and is widely used in almost all sulfur- or sulfur-donor-cured rubber formulations. Compared to vulcanization systems without zinc oxide activation, the addition of zinc oxide can significantly improve the vulcanization reaction rate, increase the crosslinking density of the rubber compound, and enhance its resistance to reversion. In existing rubber compounding technologies, zinc (Zn) remains the transition metal element with the best activation effect and the highest practical value, and its activation role in the vulcanization process holds an irreplaceable core position.

[0003] However, due to environmental pressures and cost burdens, the rubber processing industry is seeking effective alternatives to reduce zinc oxide usage. Currently, the main technological approaches include three categories: organic zinc, nano-zinc oxide, and zinc-loaded inorganic fillers. While organic zinc compounds can directly provide active Zn²⁺... + However, zinc oxide has low effective zinc content, high cost, and poor dispersibility in rubber compounds, resulting in insufficient uniformity of the crosslinking network and a lack of neutralization ability for vulcanization byproducts, significantly reducing its anti-reversion performance. Nano-zinc oxide increases reactivity by increasing specific surface area, but its nanoparticles are prone to aggregation and are difficult to disperse effectively in rubber. Poor dispersion prevents nano-zinc oxide from functioning effectively in practical applications, and its preparation process is complex and costly. Inorganic filler-loaded zinc technology, by loading zinc species onto the surface of carriers such as calcium carbonate, promises to improve zinc atom utilization, but the introduction of large amounts of inert fillers dilutes the rubber phase, causing a decrease in mechanical properties and increased hysteresis loss. In actual production, such materials often exhibit significant vulcanization reversion, affecting the stability and durability of the vulcanized rubber network.

[0004] In summary, existing zinc reduction technologies all have significant shortcomings, failing to significantly reduce the zinc content in the formulation while ensuring that the rubber compound's performance does not deteriorate. Therefore, developing a novel zinc-based activator with high zinc atom utilization, good dispersibility, strong process adaptability, and the ability to balance rubber compound performance has become a pressing technical challenge for the rubber industry. Summary of the Invention

[0005] This invention utilizes polyvinylpyrrolidone as a template agent to prepare a zinc-magnesium-aluminum ternary nanocomposite material with specific microstructure and chemical composition via a controlled precipitation method. Applying this material to rubber compositions can significantly reduce the zinc content in the formulation without deteriorating the processing and mechanical properties of the rubber compound, thereby reducing zinc emissions from tires and environmental pollution.

[0006] The specific technical solution to achieve the above-mentioned objectives is as follows: This invention provides a zinc-magnesium-aluminum ternary nanocomposite material with the chemical composition Zn. x Mg y Al z O, where x+y+(3 / 2)z=1, and 0.5≤x≤0.9, 0.04≤y≤0.4, 0.04≤z≤0.2; and the BET specific surface area of ​​the ternary nanocomposite material is 40~150 m² / g, and the porosity is ≥0.15 cm³ / g.

[0007] Furthermore, the preparation method of the zinc-magnesium-aluminum ternary nanocomposite material includes the following steps: Preparation of S1 solution: (a) Prepare a mixed salt solution of zinc, magnesium, and aluminum salts; (b) Add template agent and dispersant to the mixed salt solution, stir and mix at room temperature to obtain a mother liquor A with uniform composition; (c) Prepare a mixed aqueous solution of sodium carbonate and sodium hydroxide as precipitant solution B, wherein the pH value of precipitant solution B is 10.0-11.0; S2 coprecipitation reaction: Under shear conditions of 50~80℃ and 1000~8000 rpm, mother liquor A and precipitant solution B were added to the reactor in parallel flow. The pH of the reaction system was controlled at 9.0~10.0 to carry out co-precipitation reaction. After the reaction was completed, the mixture was aged at the reaction temperature for 0.2~1.5 h to obtain the precursor slurry. S3 Washing and Filtration: The precursor slurry was filtered to obtain a filter cake; the filter cake was washed with deionized water until no sulfate ions were detected in the filtrate. S4 slurry pretreatment and spray drying: The washed filter cake is redispersed in water to prepare a uniform slurry with a solid content of 10-20 wt%. The slurry is then spray-dried with the inlet temperature controlled at 280-320℃ and the outlet temperature controlled at 100-120℃ to obtain microspherical precursor powder. S5 calcination: The microspherical precursor powder is heated to 250-350°C in air at a heating rate of 2-5°C / min and held at that temperature for 0.5-1 h; then heated to 450-600°C at a heating rate of 3-5°C / min and calcined for 1-2 h to obtain the zinc-magnesium-aluminum ternary nanocomposite material.

[0008] Furthermore, in step S2, the flow rate control of the parallel addition is such that the feeding time lasts for 2 to 4 hours.

[0009] Further, the total metal ion concentration of the mixed salt solution in step S1 is 0.5~1.5 mol / L; Zn²⁺ + Mg² + Al³ + The molar concentration ratio is (0.6-0.8):(0.1-0.3):0.1.

[0010] Further, the Zn in the mixed salt solution described in step S1 2+ The concentration is 0.25~1.35 mol / L, Mg 2+ The concentration was 0.025~0.60 mol / L, Al 3+ The concentration is 0.025~0.30 mol / L.

[0011] Preferably, the Zn 2+ The concentration was 0.30~1.20 mol / L, Mg 2+ The concentration was 0.15~0.45 mol / L, Al 3+ The concentration is 0.15~0.30 mol / L. Further, the template agent in S1 is polyvinylpyrrolidone, and the concentration of the template agent in the mother liquor A is 0.1~5wt%; the dispersant is sodium citrate, and the concentration of the dispersant in the mother liquor A is 0.1~5wt%.

[0012] Preferably, the dispersant concentration is 0.5~2.0 wt%.

[0013] Furthermore, the zinc salt is derived from at least one of sulfate, hydrochloride, and acetate; the magnesium salt is derived from one or more of sulfate and hydrochloride; and the aluminum salt is derived from one or more of sulfate.

[0014] Preferably, the zinc salt, magnesium salt, and aluminum salt in the mixed salt solution are all sulfates.

[0015] Furthermore, the template agent is PVP K30, with a concentration of 0.2~1.0wt%.

[0016] Furthermore, in the precipitant solution B described in S1, the molar ratio of carbonate ions to hydroxide ions is 1:(0.5-2).

[0017] The present invention also provides a rubber composition comprising an elastomer, reinforcing filler, crosslinking system, and the ternary nanocomposite material.

[0018] Furthermore, the content of the ternary nanocomposite material in the rubber composition is 0.5~10 phr / 100 phr elastomer by weight.

[0019] Further, the crosslinking system comprises: Sulfur or sulfur donor as a crosslinking agent; At least one accelerator, said accelerator being selected from thiazole compounds, sulfenamide compounds, thiuram compounds, and guanidine compounds; and Stearic acid as an activator.

[0020] Furthermore, the elastomer is an elastomer composition with natural or synthetic elastomers containing unsaturated structures in the main chain as the main component.

[0021] Furthermore, the elastomer is selected from: (1) Butadiene homopolymer, isoprene homopolymer, copolymer of butadiene and isoprene; (2) Butadiene, isoprene and compounds selected from ethylene, propylene, C4 A copolymer of at least one monomer from C8 olefins and styrene; or (3) A mixture of any two or more polymers in (1) and (2) above.

[0022] Furthermore, the reinforcing filler refers to a composition whose main components are carbon black aggregates or amorphous silica aggregates or a mixture thereof.

[0023] The amount of the reinforcing filler is 5~160 phr, preferably 10~120 phr.

[0024] Preferably, the reinforcing filler is carbon black aggregate, especially carbon black of the N100, N200, N300, N400, N500, and N600 series and their mixtures according to the ASTM classification, preferably present at a content of 10 to 60 phr.

[0025] Preferably, the reinforcing filler is an amorphous silica aggregate, especially NSA with a specific surface area between 50 and 500 m². 2 / g of precipitated hydrated silica, preferably present at a content of 40~120 phr.

[0026] The present invention also provides the use of the rubber composition described herein in the preparation of tires.

[0027] It should be noted that the proportions of metal ions in the mixed salt solution used in the experiment do not strictly correspond to the chemical composition of the final product. The concentration of the precipitant is very low, and only a small portion of the metal salts actually participates in the reaction.

[0028] This invention utilizes polyvinylpyrrolidone (PVP) as a template agent to prepare a zinc-magnesium-aluminum ternary nanocomposite material with controllable particle size and composition via a controlled precipitation method. The aim is to control the microstructure and composition of the nanocomposite material, thereby endowing it with an extremely high specific surface area while reducing its surface energy and improving its dispersibility in rubber, thus significantly enhancing the atomic utilization rate of zinc. Ultimately, the zinc content in the formulation can be significantly reduced without deteriorating the performance of the rubber compound. Thanks to the extremely high specific surface area and excellent dispersibility of the zinc-magnesium-aluminum ternary nanocomposite material prepared by this invention, the formation of the vulcanization crosslinking network is more uniform, thereby improving the fatigue resistance of the rubber compound and effectively reducing dynamic heat generation. Furthermore, due to its broad reaction interface, this composite material can more efficiently capture and neutralize acidic byproducts (such as H2S) generated during vulcanization compared to traditional zinc oxide, thereby further delaying vulcanization reversion and enhancing network stability.

[0029] Furthermore, the process of this invention is simple, economical, and the products are widely adaptable. By adjusting the reactant concentration, shear rate, calcination temperature, and other process parameters, nanocomposite materials with different compositions and BET specific surface areas can be obtained relatively easily, thereby meeting the requirements of different formulation systems.

[0030] The "specific microstructure" of this invention refers to the specific specific surface area and porosity of the ternary nanocomposite material. The BET specific surface area prepared by this invention is 40~150 m². 2 / g, porosity ≥0.15 cm 3 / g. Detailed Implementation

[0031] To facilitate understanding of the present invention, a more complete description is provided below. The present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the present invention. Unless otherwise defined, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. The term "and / or" as used in this invention includes any and all combinations of one or more of the associated listed items.

[0032] This invention can be implemented in the following ways, and for processes and parameters not specified herein, conventional techniques can be used. The preparation examples and embodiments described below provide the zinc-magnesium-aluminum ternary nanocomposite material with specific microstructure and chemical composition as described in any of the foregoing preferred embodiments, and its preparation method, as well as a rubber composition containing such material and its preparation method, specifically as follows: Preparation Example 1: (1) Add ZnSO4·7H2O, MgSO4·7H2O, and Al2(SO4)3·18H2O to a mixing tank containing deionized water. Stir at 50 rpm for 20 min, then add sodium citrate and continue stirring at 50 rpm for 10 min. Heat the system to 50℃, add PVP K30 at 100 rpm, and continue stirring at this temperature for 30 min. This yields Zn. 2+ Concentration of 0.6 mol / L, Mg 2+ Concentration of 0.3 mol / L, Al 3+ Mother liquor A has a concentration of 0.1 mol / L, sodium citrate concentration of 0.4 wt%, and PVP concentration of 0.8 wt%. Sodium carbonate and sodium hydroxide are added to a mixing tank containing deionized water to prepare a precipitant solution B with a Na2CO3 concentration of 0.001 mol / L and a NaOH concentration of 0.001 mol / L.

[0033] (2) Under the shear conditions of 50℃ and 6000 rpm, the mother liquor A and the precipitant solution B were added in parallel to the high-speed shear emulsifier. The co-precipitation reaction was carried out under the condition that the pH of the reaction system was controlled at 10. After the reaction was completed, the mixture was aged at the reaction temperature for 1 h to obtain the precursor slurry.

[0034] (3) The precursor slurry is vacuum filtered to obtain a filter cake; the filter cake is washed with deionized water until no sulfate ions are detected in the filtrate.

[0035] (4) The washed filter cake is mixed with deionized water to prepare a uniform slurry with a solid content of 10 wt%; the slurry is spray-dried, with the inlet temperature controlled at 300±10℃ and the outlet temperature controlled at 110±5℃ to obtain microspherical precursor powder.

[0036] (5) The precursor powder was heated to 300°C in air at a heating rate of 5°C / min and held at that temperature for 0.5 h; then calcined at 500°C for 1 h at a heating rate of 5°C / min. The zinc-magnesium-aluminum ternary nanocomposite material with a porous structure (a) was obtained.

[0037] Preparation Example 2: (1) The solution preparation process is the same as in Example 1.

[0038] (2) Under shear conditions of 50℃ and 3000 rpm, the mixed salt solution and the precipitant solution were added in parallel to a high-speed shear emulsifier. Co-precipitation reaction was carried out under the condition that the pH of the reaction system was controlled at 10. After the reaction was completed, the mixture was aged at the reaction temperature for 1 h to obtain the precursor slurry.

[0039] (3) The precursor slurry is vacuum filtered and the filter cake is washed with deionized water until no sulfate ions are detected in the filtrate.

[0040] (4) The washed filter cake is mixed with deionized water to form a uniform slurry with a solid content of 10 wt%; the slurry is spray-dried, with the inlet temperature controlled at 300±10℃ and the outlet temperature controlled at 110±5℃ to obtain microspherical precursor powder.

[0041] (5) The precursor powder was heated to 300°C in air at a heating rate of 5°C / min and held at that temperature for 0.5 h; then calcined at 550°C for 1 h at a heating rate of 5°C / min. The zinc-magnesium-aluminum ternary nanocomposite material with a porous structure (b) was obtained.

[0042] Preparation Example 3: (1) The solution preparation process is the same as in Example 1.

[0043] (2) Under shear conditions of 50℃ and 1000 rpm, the mixed salt solution and the precipitant solution were added in parallel to a high-speed shear emulsifier. Co-precipitation reaction was carried out under the condition that the pH of the reaction system was controlled at 10. After the reaction was completed, the mixture was aged at the reaction temperature for 1 h to obtain the precursor slurry.

[0044] (3) The precursor slurry is vacuum filtered and the filter cake is washed with deionized water until no sulfate ions are detected in the filtrate.

[0045] (4) The washed filter cake is mixed with deionized water to form a uniform slurry with a solid content of 10 wt%; the slurry is spray-dried, with the inlet temperature controlled at 300±10℃ and the outlet temperature controlled at 110±5℃ to obtain microspherical precursor powder.

[0046] (5) The precursor powder was heated to 300°C in air at a heating rate of 5°C / min and held at that temperature for 0.5 h; then calcined at 600°C for 1 h at a heating rate of 5°C / min. The zinc-magnesium-aluminum ternary nanocomposite material with a porous structure (c) was obtained.

[0047] Preparation Example 4: (1) Add ZnSO4·7H2O, MgSO4·7H2O, and Al2(SO4)3·18H2O to a mixing tank containing deionized water. Stir at 50 rpm for 20 min, then add sodium citrate to the mixing tank and continue stirring at 50 rpm for 10 min. Heat the system to 50℃, add PVP K30 at 100 rpm, and continue stirring at this temperature for 30 min. The resulting mother liquor A has a Zn2+ concentration of 0.7 mol / L, a Mg2+ concentration of 0.2 mol / L, an Al3+ concentration of 0.1 mol / L, a sodium citrate concentration of 0.4 wt%, and a PVP concentration of 0.8 wt%.

[0048] Sodium carbonate and sodium hydroxide were added to a mixing tank containing deionized water to prepare a precipitant solution B with a Na2CO3 concentration of 0.001 mol / L and a NaOH concentration of 0.001 mol / L.

[0049] (2) Under shear conditions of 50℃ and 3000 rpm, the mixed salt solution and the precipitant solution were added in parallel to a high-speed shear emulsifier. Co-precipitation reaction was carried out under the condition that the pH of the reaction system was controlled at 10. After the reaction was completed, the mixture was aged at the reaction temperature for 0.5 h to obtain the precursor slurry.

[0050] (3) The slurry filtration and washing process is the same as in preparation example 2.

[0051] (4) The slurry pretreatment and spray drying process are the same as in preparation example 2.

[0052] (5) The calcination process is the same as in Preparation Example 2. The zinc-magnesium-aluminum ternary nanocomposite material with a porous structure (d) is obtained.

[0053] Preparation Example 5: (1) Add ZnSO4·7H2O, MgSO4·7H2O, and Al2(SO4)3·18H2O to a mixing tank containing deionized water. Stir at 50 rpm for 20 min, then add sodium citrate to the mixing tank and continue stirring at 50 rpm for 10 min. Heat the system to 50℃, add PVP K30 at 100 rpm, and continue stirring at this temperature for 30 min. The resulting mother liquor A has a Zn2+ concentration of 0.8 mol / L, a Mg2+ concentration of 0.1 mol / L, an Al3+ concentration of 0.1 mol / L, a sodium citrate concentration of 0.4 wt%, and a PVP concentration of 0.8 wt%.

[0054] Sodium carbonate and sodium hydroxide were added to a mixing tank containing deionized water to prepare a precipitant solution B with a Na2CO3 concentration of 0.001 mol / L and a NaOH concentration of 0.001 mol / L.

[0055] (2) Under shear conditions of 50℃ and 3000 rpm, the mixed salt solution and the precipitant solution were added in parallel to a high-speed shear emulsifier. Co-precipitation reaction was carried out under the condition that the pH of the reaction system was controlled at 10. After the reaction was completed, the mixture was aged at the reaction temperature for 0.2 h to obtain the precursor slurry.

[0056] (3) The slurry filtration and washing process is the same as in preparation example 2.

[0057] (4) The slurry pretreatment and spray drying process are the same as in preparation example 2.

[0058] (5) The calcination process is the same as in Preparation Example 2. The zinc-magnesium-aluminum ternary nanocomposite material with a porous structure (e) is obtained.

[0059] The products obtained from Preparation Examples 1-5, indirect zinc oxide, and nano zinc oxide materials were tested. The chemical composition, specific surface area, and porosity of each material are shown in Table 1. Table 1

[0060] The chemical composition test method for the test materials was based on ASTM E1479, the specific surface area test method was based on ASTM D6556, and the porosity test method was based on ASTM D4404.

[0061] Example 1: A rubber composition, comprising, by weight, the following components: 80 phr of standard natural rubber No. 20, 20 phr of nickel-based cis-butadiene rubber, 50 phr of carbon black N220, 15 phr of silica 160, 1.2 phr of silane coupling agent, 1 phr of antioxidant 6PPD, 1 phr of antioxidant RD, 1 phr of antioxidant P wax, 1.5 phr of sulfur, 1.6 phr of accelerator NS, 3 phr of stearic acid, and 5 phr of the ternary nanocomposite material (a) described in Example 1.

[0062] The preparation process is as follows: 1) At an initial temperature of 50°C, standard natural rubber No. 20 and nickel-based cis-butadiene rubber were added to a mixer and mixed at 60 rpm for 30 seconds. After 30 seconds, the plug was raised and carbon black, antioxidant 6PPD, antioxidant RD, P wax, stearic acid, and the ternary nanocomposite material (a) described in Example 1 were added sequentially. The mixture was then continued to be mixed at 60 rpm for 120 seconds, and after 10 seconds of plugging, it was continued to be mixed at 60 rpm for 90 seconds or discharged at 165°C. A first-stage masterbatch M1 was obtained.

[0063] 2) Add the cooled masterbatch M1 to a Banbury mixer and mix at 60 rpm for 30 seconds. After 30 seconds, raise the plug and add silica and silane coupling agent in sequence, and continue mixing at 60 rpm for 50 seconds. After raising the plug for 10 seconds, continue mixing at 60 rpm for 90 seconds or discharge the rubber at 155°C. This yields the second-stage masterbatch M2.

[0064] 3) Add the cooled masterbatch M2, sulfur, and accelerator to the internal mixer in sequence and mix at 40 rpm. Raise the throttle once every 30 seconds during the mixing process. Discharge the rubber at 180 seconds or 115°C to obtain the final rubber.

[0065] 4) Add the final rubber compound to the mold and vulcanize it at 150°C for 25 minutes to obtain the rubber composition.

[0066] Example 2: The only difference between the rubber composition formulation and Example 1 is that the zinc-magnesium-aluminum ternary nanocomposite material (b) prepared in Preparation Example 2 is used instead of the ternary nanocomposite material (a) described in Preparation Example 1. The preparation process is the same as in Example 1.

[0067] Example 3: The only difference between the rubber composition formulation and Example 1 is that the zinc-magnesium-aluminum ternary nanocomposite material (c) prepared in Preparation Example 3 is used instead of the ternary nanocomposite material (a) described in Preparation Example 1. The preparation process is the same as in Example 1.

[0068] Example 4: The only difference between the rubber composition formulation and Example 1 is that the zinc-magnesium-aluminum ternary nanocomposite material (d) prepared in Preparation Example 4 is used instead of the ternary nanocomposite material (a) described in Preparation Example 1. The preparation process is the same as in Example 1.

[0069] Example 5: The only difference between the rubber composition formulation and Example 1 is that the zinc-magnesium-aluminum ternary nanocomposite material (e) prepared in Preparation Example 5 is used instead of the ternary nanocomposite material (a) described in Preparation Example 1. The preparation process is the same as in Example 1.

[0070] Example 6: The only difference between the rubber composition formulation and Example 1 is that the zinc-magnesium-aluminum ternary nanocomposite material (d) prepared in Preparation Example 4 is used instead of the ternary nanocomposite material (a) described in Preparation Example 1, and the amount of composite material (d) is 4.5 phr. The preparation process is the same as in Example 1.

[0071] Example 7: The only difference between the rubber composition formulation and Example 1 is that the zinc-magnesium-aluminum ternary nanocomposite material (d) prepared in Preparation Example 4 is used instead of the ternary nanocomposite material (a) described in Preparation Example 1, and the amount of composite material (d) is 4 phr. The preparation process is the same as in Example 1.

[0072] Example 8: The only difference between the rubber composition formulation and Example 1 is that the zinc-magnesium-aluminum ternary nanocomposite material (d) prepared in Preparation Example 4 is used instead of the ternary nanocomposite material (a) described in Preparation Example 1, and the amount of composite material (d) is 3.5 phr. The preparation process is the same as in Example 1.

[0073] Example 9: The only difference between the rubber composition formulation and Example 1 is that the zinc-magnesium-aluminum ternary nanocomposite material (d) prepared in Preparation Example 4 is used instead of the ternary nanocomposite material (a) described in Preparation Example 1, and the amount of composite material (d) is 3 phr. The preparation process is the same as in Example 1.

[0074] Comparative Example 1: The only difference between the rubber composition formulation and Example 1 is that the composite material prepared according to this invention is omitted. The preparation process is the same as in Example 1.

[0075] Comparative Example 2: The only difference between the rubber composition formulation and Example 1 is that 5 phr of indirect zinc oxide was used instead of zinc oxide (a) in the preparation of the ternary nanocomposite material described in Example 1. The preparation process was the same as in Example 1.

[0076] Comparative Example 3: The only difference between the formulation of the rubber composition and that of Example 1 is that nano-zinc oxide 3 phr is used instead of the ternary nanocomposite material (a) described in Example 1. The preparation process is the same as in Example 1.

[0077] Performance tests were conducted on the products of the above embodiments and comparative examples. The test results of vulcanization characteristics are shown in Table 2, and the test results of mechanical properties are shown in Table 3. The crosslinking density of the rubber compound after vulcanization is represented by the difference (MH-ML) between the highest torque (MH) and the lowest torque (ML) in the rheological curve; the vulcanization rate is represented by the time (t90) for the rubber compound torque to reach ML+0.9*(MH-ML); the vulcanization reversion rate Re is represented by the ratio of the difference between the highest torque (MH) and the final torque (MF) to the crosslinking density (MH-ML), which reflects the stability of the rubber crosslinking network. Among them, the highest torque (MH) and the lowest torque (ML) were obtained by testing with reference to GB / T16584-1996.

[0078] Table 2

[0079] According to the comparison of the data of Examples 1-5 with Comparative Examples 1 and 2 in Table 2, under the same addition amount, the zinc-magnesium-aluminum ternary nanocomposite material prepared by the present invention can achieve vulcanization characteristics similar to those of indirect zinc oxide, including crosslinking density, vulcanization rate and network stability. Further comparison of Examples 6-9 with Comparative Examples 2 and 3 shows that even when the amount of this composite material is reduced to 60% of that of indirect zinc oxide (Example 9), it can still maintain a comparable level of vulcanization performance; while under the same reduction conditions (Comparative Example 3), nano zinc oxide shows a significant decrease in its resistance to reversion to vulcanization, reflecting its insufficient crosslinking network stability under low dosage conditions.

[0080] Table 3

[0081] According to the comparison of the data of Examples 1-5 with Comparative Examples 1 and 2 in Table 3, under the same addition amount, the mechanical properties of the technical solution provided by the present invention are basically equivalent to those of the indirect zinc oxide material. Furthermore, the comparison results of Examples 6-9 with Comparative Examples 2 and 3 show that even if the amount of this composite material is reduced to 60% of that of indirect zinc oxide, it can still maintain comparable mechanical properties, while under the same reduction conditions, the mechanical properties of nano zinc oxide decrease significantly after aging.

[0082] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A zinc-magnesium-aluminum ternary nanocomposite material, characterized in that, The chemical composition is Zn x Mg y Al z O, where x+y+(3 / 2)z=1, 0.5≤x≤0.9, 0.04≤y≤0.4, 0.04≤z≤0.2; the BET specific surface area of ​​the ternary nanocomposite material is 40~150 m². 2 / g, porosity ≥0.15 cm 3 / g.

2. A method for preparing the zinc-magnesium-aluminum ternary nanocomposite material as described in claim 1, characterized in that, Includes the following steps: Preparation of S1 solution: (a) Prepare a mixed salt solution of zinc, magnesium, and aluminum salts; (b) Add template agent and dispersant to the mixed salt solution, stir and mix at room temperature to obtain a mother liquor A with uniform composition; (c) Prepare a mixed aqueous solution of sodium carbonate and sodium hydroxide as precipitant solution B, wherein the pH value of precipitant solution B is 10.0-11.0; S2 coprecipitation reaction: Under shear conditions of 50~80℃ and 1000~8000 rpm, mother liquor A and precipitant solution B are added to the reactor in parallel flow. The pH of the reaction system is controlled at 9.0~10.0 to carry out co-precipitation reaction. After the reaction is completed, the mixture is aged at the reaction temperature for 0.2~1.5h to obtain the precursor slurry. S3 Washing and Filtration: The precursor slurry was filtered to obtain a filter cake; the filter cake was washed with deionized water until no sulfate ions were detected in the filtrate. S4 slurry pretreatment and spray drying: The washed filter cake is redispersed in water to prepare a uniform slurry with a solid content of 10-20 wt%. The slurry is then spray-dried with the inlet temperature controlled at 280-320℃ and the outlet temperature controlled at 100-120℃ to obtain microspherical precursor powder. S5 calcination: The microspherical precursor powder is heated to 250-350°C in air at a heating rate of 2-5°C / min and held at that temperature for 0.5-1 h; then heated to 450-600°C at a heating rate of 3-5°C / min and calcined for 1-2 h to obtain the zinc-magnesium-aluminum ternary nanocomposite material.

3. The preparation method according to claim 2, characterized in that, The total metal ion concentration of the mixed salt solution described in S1 is 0.5~1.5 mol / L; Zn² + Mg² + Al³ + The molar concentration ratio is (0.6-0.8):(0.1-0.3):0.

1.

4. The preparation method according to claim 2, characterized in that, The template agent in S1 is polyvinylpyrrolidone, and the concentration of the template agent in the mother liquor A is 0.1~5wt%; the dispersant is sodium citrate, and the concentration of the dispersant in the mother liquor A is 0.1~5wt%.

5. A rubber composition, characterized in that, It includes elastomers, reinforcing fillers, crosslinking systems, and ternary nanocomposites as described in claim 1.

6. The rubber composition according to claim 5, characterized in that, The content of ternary nanocomposite material in the rubber composition is 0.5~10 phr / 100 phr elastomer by weight.

7. The rubber composition according to claim 5, characterized in that, The crosslinking system comprises: Sulfur or sulfur donor as a crosslinking agent; At least one accelerator, said accelerator being selected from thiazole compounds, sulfenamide compounds, thiuram compounds, and guanidine compounds; and Stearic acid as an activator.

8. The rubber composition according to claim 5, characterized in that, The elastomer is selected from: (1) Butadiene homopolymer, isoprene homopolymer, copolymer of butadiene and isoprene; (2) Butadiene, isoprene and compounds selected from ethylene, propylene, C4 A copolymer of at least one monomer from C8 olefins and styrene; or (3) A mixture of any two or more polymers in (1) and (2) above.

9. The rubber composition according to claim 5, characterized in that, The amount of the reinforcing filler used is 5~160 phr.

10. The use of a rubber composition as described in claims 5-9 in the manufacture of tires.

Images