Self-repairing intelligent asphalt pavement material and preparation method thereof

Abstract

The invention relates to a self-repairing intelligent asphalt pavement material and a preparation method thereof. The self-repairing intelligent asphalt pavement material comprises the following components in parts by mass: 500-700 parts of asphalt, 150-250 parts of a polyurethane compound and 80-120 parts of water, the polyurethane compound is prepared from waterborne polyurethane, a self-repairing microcapsule and a modified nano filler. The method has the effect of improving the self-repairing performance of the asphalt material.

Description

Technical Field

[0001] This application relates to the field of asphalt, and in particular to a self-healing intelligent asphalt pavement material and its preparation method. Background Technology

[0002] Asphalt pavement refers to various types of road surfaces constructed by incorporating road asphalt materials into mineral materials. Asphalt binders improve the ability of paving aggregates to resist damage to the road surface from traffic and natural factors, resulting in a smooth, dust-free, impermeable, and durable road surface.

[0003] Currently, while traditional asphalt pavement materials are widely used in highway construction and maintenance, they generally suffer from poor durability and susceptibility to cracking due to temperature and humidity changes. With technological advancements, researchers are exploring new composite materials to improve pavement self-healing capabilities and enable intelligent management. Summary of the Invention

[0004] To address the aforementioned issues, this application provides a self-healing intelligent asphalt pavement material and its preparation method.

[0005] Firstly, this application provides a self-healing intelligent asphalt pavement material, which adopts the following technical solution: A self-healing intelligent asphalt pavement material, comprising the following components by weight: 500-700 parts asphalt, 150-250 parts polyurethane composite, 80-120 parts water; The polyurethane composite comprises aqueous polyurethane, self-healing microcapsules, and modified nanofillers.

[0006] By adopting the above technical solution, self-healing microcapsules are added to the asphalt system to endow the material with self-healing properties. The self-healing microcapsules are prepared by embedding the repair agent with polymer film-forming materials to obtain a core-shell structure, which can repair the damaged material in time, thereby improving the overall durability of the asphalt. Modified nanofillers are also added to the system, which can further improve the mechanical strength of polyurethane, making the polyurethane composite more stable in the asphalt system, and playing a role in improving the self-healing performance and strength of asphalt.

[0007] Preferably, the raw materials for the self-healing microcapsules include tetraethyl orthosilicate, ethyl cellulose, silica, and epoxy resin.

[0008] By adopting the above technical solution, using tetraethyl orthosilicate as the silicon source, ethyl cellulose as the wall material, and epoxy resin as the profile, the prepared self-healing microcapsules have good self-healing properties and good compatibility with waterborne polyurethane, thereby further improving the overall stability of the system.

[0009] Preferably, the self-healing microcapsules are prepared by the following method: Hydrochloric acid and ethanol were mixed to obtain a hydrochloric acid alcohol solution. Ethyl acetate and tetraethyl orthosilicate were added to the hydrochloric acid alcohol solution, and the mixture was heated and stirred to obtain a silicon solution. Ethyl cellulose was added to the silicon solution, and after stirring, 3-(2-aminoethylamino)propyltriethoxysilane was added, followed by epoxy resin. After stirring, an oil phase was obtained. Sodium dodecylbenzenesulfonate and gum arabic were mixed and added to a saturated ethyl acetate solution. After mixing, an aqueous phase was obtained. The oil phase was added to the aqueous phase and emulsified to obtain an emulsion system. Nano-silica was mixed with water, ultrasonically dispersed, and then added to the emulsion system to obtain a mixture. The mixture was heated and stirred, cooled, filtered, washed, and dried to obtain self-healing microcapsules.

[0010] By adopting the above technical solution, using epoxy resin as a repair agent, self-healing microcapsules are prepared by emulsion solvent diffusion method. Ethyl cellulose, tetraethyl orthosilicate, and epoxy resin are dissolved in ethyl acetate to obtain an oil phase, and then an aqueous solution of ethyl acetate is used as the aqueous phase. After compounding, an emulsion is obtained. The tetraethyl orthosilicate in the oil phase is hydrolyzed into silanol, which is then crosslinked and precipitated on ethyl cellulose under the action of a silane coupling agent to obtain a silica structure, thereby preparing self-healing microcapsules. The pore size of the prepared self-healing microcapsules is improved, and the roughness of the self-healing microcapsules is further improved, thereby further improving the compatibility between the self-healing microcapsules and waterborne polyurethane, thus further improving the stability of the polyurethane system in asphalt.

[0011] Preferably, the mass ratio of ethyl cellulose to tetraethyl orthosilicate is 1:(1.2-1.4).

[0012] By adopting the above technical solution, and preferably keeping the mass ratio of ethyl cellulose to tetraethyl orthosilicate within the above range, the stability of the prepared self-healing microcapsules can be further improved.

[0013] Preferably, the mass ratio of the epoxy resin, ethyl cellulose and silica is 2:1:(0.03-0.05).

[0014] By adopting the above technical solution, and preferably within the above-mentioned range the mass ratio of epoxy resin, ethyl cellulose and silica, the stability of the prepared self-healing microcapsules can be further improved.

[0015] Preferably, the modified nanofiller comprises octaaminopropyl polysilsesquioxane and alumina.

[0016] By adopting the above technical solution, octaaminopropyl polysilsesquioxane is a compound with an inorganic-organic hybrid structure. When combined with alumina, it can improve the mechanical and thermal stability of alumina and enhance the overall dispersion performance of alumina. This improves the stability of the modified nanofiller in waterborne polyurethane, thereby enhancing the overall stability of the polyurethane composite system.

[0017] Preferably, the modified nanofiller is prepared by the following method: Water, isopropanol and alumina were mixed and sonicated to obtain an alumina dispersion. Octaaminopropyl polysilsesquioxane was added to the alumina dispersion, heated and stirred, then centrifuged, washed and dried to obtain the modified nanofiller.

[0018] By adopting the above technical solution, octaaminopropyl polysilsesquioxane with abundant amino groups is first prepared and synthesized using KH-550 as raw material. Then, alumina is modified so that the surface of alumina particles is coated with a thin film of organic-inorganic compounds, thereby improving the particle size of nano-alumina and relatively reducing the specific surface area. This reduces the phenomenon of alumina particle agglomeration, allowing alumina to be stably distributed in the system. At the same time, it improves the compatibility of alumina in the system and enhances the overall stability of the system.

[0019] Preferably, the mass ratio of the octaaminopropyl polysilsesquioxane to alumina is (5.2-5.6):1.

[0020] By adopting the above technical solution, and preferably within the above range the mass ratio of octaaminopropyl polysilsesquioxane to alumina, the stability of the prepared modified nanofiller can be further improved.

[0021] Preferably, the mass ratio of the waterborne polyurethane, self-healing microcapsules and modified nanofiller is 1:(0.12-0.14):0.05.

[0022] By adopting the above technical solution, and optimizing the mass ratio of waterborne polyurethane, self-healing microcapsules, and modified nanofillers within the above range, the overall stability of the prepared polyurethane composite can be further improved.

[0023] Secondly, this application provides a method for preparing a self-healing intelligent asphalt pavement material, employing the following technical solution: A method for preparing a self-healing intelligent asphalt pavement material includes the following steps: After mixing polyurethane composite, asphalt and water, a self-healing asphalt pavement material is obtained by stirring.

[0024] In summary, this application includes at least one of the following beneficial technical effects: 1. A polyurethane composite, prepared from waterborne polyurethane, self-healing microcapsules, and modified nanofillers, is added to the asphalt substrate. The self-healing microcapsules are prepared by embedding the repair agent with a polymer film-forming material. The waterborne polyurethane is dispersed in the asphalt, which can repair the cracks in time when cracks appear in the asphalt, thereby improving the durability of the asphalt. At the same time, modified nanofillers are also added to the system to further reinforce the polyurethane, thereby improving the overall mechanical strength of the waterborne polyurethane. This further improves the mechanical properties of the prepared asphalt system and enhances the overall stability and service life of the asphalt. 2. Using epoxy resin as a repair agent, self-healing capsules were prepared by emulsion solvent diffusion method. Ethyl cellulose, tetraethyl orthosilicate, and epoxy resin were dissolved in ethyl acetate to obtain an oil phase. Then, an aqueous solution of ethyl acetate was used as a water tank to prepare an emulsion. The tetraethyl orthosilicate in the oil phase was hydrolyzed to generate silanol, which was then cross-linked and precipitated on ethyl cellulose under the action of a silane coupling agent to obtain a silica structure, thereby preparing self-healing microcapsules. The pore size of the prepared self-healing microcapsules was further improved, and the roughness of the self-healing microcapsules was also improved, which further improved the compatibility between the self-healing microcapsules and waterborne polyurethane, thereby further improving the stability of the polyurethane composite in the asphalt system. 3. Modifying alumina with octaaminopropyl polysilsesquioxane results in a thin film of organic-inorganic compounds coating the surface of alumina particles. This improves the particle size of nano-alumina, reduces the specific surface area, and decreases the agglomeration of alumina particles, thereby enhancing the dispersibility of alumina in the system and improving the stability of the polyurethane system. Detailed Implementation

[0025] The present application will be further described in detail below with reference to the embodiments: Raw material description: All raw materials used in the examples are commercially available; Example 1 Preparation of octaaminopropyl polysilsesquioxane: 300g of deionized water, 120g of propanol, 30g of acetonitrile, and 6g of tetramethylammonium hydroxide were mixed to obtain a composite solution. 330g of aminopropyltriethoxysilane was added while stirring. The mixture was heated to 50°C in a water bath and the temperature was maintained for 12 hours. After the reaction, 300g of tetrahydrofuran was added to precipitate the product. The product was then filtered and washed three times alternately with deionized water and n-hexane. Finally, it was dried at 80°C for 18 hours to obtain octaaminopropyl polysilsesquioxane.

[0026] Preparation of modified nanofillers: 250g of deionized water, 250g of isopropanol, and 15g of alumina were mixed. The pH of the system was adjusted to 13 using sodium hydroxide. After stirring for 10 minutes, the mixture was sonicated for 4 hours to obtain an alumina dispersion. 78g of octaaminopropyl polysilsesquioxane was added to the alumina dispersion. The mixture was heated to 50℃ and stirred for 4 hours. Then, it was centrifuged at 6000 rpm for 5 minutes. After washing with deionized water, the mixture was dried at 60℃ for 12 hours and then ground to obtain the modified nanofiller.

[0027] Preparation of self-healing microcapsules: Hydrochloric acid was added to ethanol to obtain a 0.1 mol / L hydrochloric acid-alcohol solution. 70 g of ethyl acetate and 18 g of tetraethyl orthosilicate were added to 15 mL of the hydrochloric acid-alcohol solution. The mixture was heated to 40 °C under sealed conditions and then stirred for 1 h to obtain a silica solution. 15 g of ethyl cellulose was added to the silica solution, and after stirring, 0.18 g of 3-(2-aminoethylamino)propyltriethoxysilane was added, followed by 30 g of epoxy resin. After stirring, an oil phase was obtained. 1.2 g of sodium dodecylbenzenesulfonate and 12 g of gum arabic were mixed... Add the oil phase to a saturated ethyl acetate solution and mix to obtain an aqueous phase. Add the oil phase to the aqueous phase and emulsify by stirring at 500 rpm for 30 min to obtain an emulsion system. Mix 0.45 g of nano-silica with deionized water, disperse by ultrasonication, and add it to the emulsion system to obtain a mixture. Heat the mixture to 40 °C in a water bath and continue stirring for 6 h. Then heat the system to 60 °C and stir for another 1 h. Allow it to cool naturally to 25 °C, filter, wash with deionized water, and dry at 50 °C for 12 h to obtain self-healing microcapsules.

[0028] Preparation of polyurethane composites: 256.41g of aqueous polyurethane, 30.77g of self-healing microcapsules and 12.82g of modified nanofiller were mixed and stirred at 600rpm for 30min to obtain a polyurethane composite.

[0029] Preparation of self-healing intelligent asphalt pavement materials: Mix 150g of polyurethane composite, 500g of asphalt, and 80g of water, and then stir to obtain a self-healing asphalt pavement material.

[0030] Example 2 Preparation of octaaminopropyl polysilsesquioxane: 300g of deionized water, 120g of propanol, 30g of acetonitrile, and 6g of tetramethylammonium hydroxide were mixed to obtain a composite solution. 330g of aminopropyltriethoxysilane was added while stirring. The mixture was heated to 50°C in a water bath and the temperature was maintained for 12 hours. After the reaction, 300g of tetrahydrofuran was added to precipitate the product. The product was then filtered and washed three times alternately with deionized water and n-hexane. Finally, it was dried at 80°C for 18 hours to obtain octaaminopropyl polysilsesquioxane.

[0031] Preparation of modified nanofillers: 250g of deionized water, 250g of isopropanol, and 15g of alumina were mixed. The pH of the system was adjusted to 13 using sodium hydroxide. After stirring for 10 minutes, the mixture was sonicated for 4 hours to obtain an alumina dispersion. 81g of octaaminopropyl polysilsesquioxane was added to the alumina dispersion. The mixture was heated to 50℃ and stirred for 4 hours. Then, it was centrifuged at 6000 rpm for 5 minutes. After washing with deionized water, it was dried at 60℃ for 12 hours and then ground to obtain the modified nanofiller.

[0032] Preparation of self-healing microcapsules: Hydrochloric acid was added to ethanol to obtain a 0.1 mol / L hydrochloric acid-alcohol solution. 70 g of ethyl acetate and 19.5 g of tetraethyl orthosilicate were added to 15 mL of the hydrochloric acid-alcohol solution. The mixture was heated to 40 °C under sealed conditions and then stirred for 1 h to obtain a silica solution. 15 g of ethyl cellulose was added to the silica solution, and after stirring, 0.18 g of 3-(2-aminoethylamino)propyltriethoxysilane was added, followed by 30 g of epoxy resin. After stirring, an oil phase was obtained. 1.2 g of sodium dodecylbenzenesulfonate and 12 g of gum arabic were mixed... Add the oil phase to a saturated ethyl acetate solution and mix to obtain an aqueous phase. Add the oil phase to the aqueous phase and stir and emulsify at 500 rpm for 30 min to obtain an emulsion system. Mix 0.75 g of nano-silica with deionized water, disperse ultrasonically, and add it to the emulsion system to obtain a mixture. Heat the mixture to 40 °C in a water bath and continue stirring for 6 h. Then heat the system to 60 °C and stir for another 1 h. Allow it to cool naturally to 25 °C, filter, wash with deionized water, and dry at 50 °C for 12 h to obtain self-healing microcapsules.

[0033] Preparation of polyurethane composites: 252.1g of aqueous polyurethane, 35.29g of self-healing microcapsules and 12.61g of modified nanofiller were mixed and stirred at 600rpm for 30min to obtain a polyurethane composite.

[0034] Preparation of self-healing intelligent asphalt pavement materials: Mix 250g of polyurethane composite, 700g of asphalt, and 120g of water, and then stir to obtain a self-healing asphalt pavement material.

[0035] Example 3 Preparation of octaaminopropyl polysilsesquioxane: 300g of deionized water, 120g of propanol, 30g of acetonitrile, and 6g of tetramethylammonium hydroxide were mixed to obtain a composite solution. 330g of aminopropyltriethoxysilane was added while stirring. The mixture was heated to 50°C in a water bath and the temperature was maintained for 12 hours. After the reaction, 300g of tetrahydrofuran was added to precipitate the product. The product was then filtered and washed three times alternately with deionized water and n-hexane. Finally, it was dried at 80°C for 18 hours to obtain octaaminopropyl polysilsesquioxane.

[0036] Preparation of modified nanofillers: 250g of deionized water, 250g of isopropanol, and 15g of alumina were mixed. The pH of the system was adjusted to 13 using sodium hydroxide. After stirring for 10 minutes, the mixture was sonicated for 4 hours to obtain an alumina dispersion. 79.5g of octaaminopropyl polysilsesquioxane was added to the alumina dispersion. The mixture was heated to 50℃ and stirred for 4 hours. Then, it was centrifuged at 6000 rpm for 5 minutes. After washing with deionized water, it was dried at 60℃ for 12 hours and then ground to obtain the modified nanofiller.

[0037] Preparation of self-healing microcapsules: Hydrochloric acid was added to ethanol to obtain a 0.1 mol / L hydrochloric acid-alcohol solution. 70 g of ethyl acetate and 18.75 g of tetraethyl orthosilicate were added to 15 mL of the hydrochloric acid-alcohol solution. The mixture was heated to 40 °C under sealed conditions and then stirred for 1 h to obtain a silica solution. 15 g of ethyl cellulose was added to the silica solution, and after stirring, 0.18 g of 3-(2-aminoethylamino)propyltriethoxysilane was added, followed by 30 g of epoxy resin. After stirring, an oil phase was obtained. 1.2 g of sodium dodecylbenzenesulfonate and 12 g of gum arabic were mixed... Then, it was added to a saturated ethyl acetate solution and mixed to obtain an aqueous phase. The oil phase was added to the aqueous phase and stirred and emulsified at 500 rpm for 30 min to obtain an emulsion system. 0.6 g of nano-silica was mixed with deionized water, ultrasonically dispersed, and then added to the emulsion system to obtain a mixture. The mixture was heated to 40 °C in a water bath and stirred for 6 h. Then, the system was heated to 60 °C and stirred for another 1 h. After naturally cooling to 25 °C, it was filtered, washed with deionized water, and dried at 50 °C for 12 h to obtain self-healing microcapsules.

[0038] Preparation of polyurethane composites: 254.24 g of waterborne polyurethane, 33.05 g of self-healing microcapsules and 12.71 g of modified nanofiller were mixed and stirred at 600 rpm for 30 min to obtain a polyurethane composite.

[0039] Preparation of self-healing intelligent asphalt pavement materials: Mix 200g of polyurethane composite, 600g of asphalt, and 100g of water, and then stir to obtain a self-healing asphalt pavement material.

[0040] Example 4 Example 4 is based on Example 3. In Example 4, the amount of octaaminopropyl polysilsesquioxane used in the preparation of the modified nanofiller is 72g.

[0041] Example 5 Example 5 is based on Example 3. In Example 5, 90g of octaaminopropyl polysilsesquioxane was used when preparing the modified nanofiller.

[0042] Example 6 Example 6 is based on Example 3. In Example 6, when preparing the modified nanofiller, octaaminopropyl polysilsesquioxane was replaced with KH550.

[0043] Example 7 Example 7 is based on Example 3. In Example 7, the amount of tetraethyl orthosilicate added during the preparation of self-healing microcapsules is 16.5g.

[0044] Example 8 Example 8 is based on Example 3. In Example 8, the amount of tetraethyl orthosilicate added during the preparation of self-healing microcapsules is 21g.

[0045] Example 9 Example 9 is based on Example 3. In Example 9, 0.3g of silica was added when preparing the self-healing microcapsules.

[0046] Example 10 Example 10 is based on Example 3. In Example 10, 0.9g of silica was added when preparing the self-healing microcapsules.

[0047] Example 11 Example 11 is based on Example 3. In Example 11, when preparing the polyurethane composite, the amount of waterborne polyurethane used is 263.16g, the amount of self-healing microcapsules used is 25.68g, and the amount of modified nanofiller used is 11.16g.

[0048] Example 12 Example 12 is based on Example 3. In Example 12, when preparing the polyurethane composite, the amount of waterborne polyurethane used is 245.9g, the amount of self-healing microcapsules used is 41.8g, and the amount of modified nanofiller used is 12.3g.

[0049] Example 13 Example 13 is based on Example 3. In Example 13, the modified nanofiller was replaced with ordinary unmodified alumina when preparing the polyurethane composite.

[0050] Comparative Example 1 Comparative Example 1 is based on Example 3. In Comparative Example 1, no modified nanofiller was added when preparing the polyurethane composite.

[0051] Comparative Example 2 Comparative Example 2 is based on Example 3, but no self-healing microcapsules were added when preparing the polyurethane composite in Comparative Example 2.

[0052] Performance testing The following performance tests were performed on the samples of Examples 1-13 and Comparative Examples 1-2: Mechanical self-healing performance test: The experimental electronic universal testing machine was model MTSCMT6103, with a 500N sensor. The elongation rate of the samples before and after repair was 50 mm / min, and each group of samples was tested three times, with the average value taken. The repair efficiency was calculated using the following formula: η = (1 - Pt / P0) × 100% Wherein, P0 represents the stress and strain values ​​of the sample before repair; Pt represents the stress and strain values ​​of the sample after repair; each sample is tested three times, the average value is taken, and the test results are filled in Table 1.

[0053] Table 1 Performance test results of Examples 1-13 and Comparative Examples 1-2 Testing items Stress / kPa Post-repair stress / kPa Repair rate / % Example 1 386.4 344.2 91.3 Example 2 385.4 351.5 91.2 Example 3 390.2 358.2 91.8 Example 4 377.5 340.5 90.2 Example 5 376.2 338.6 90.0 Example 6 370.2 332.1 89.7 Example 7 382.2 330.6 86.5 Example 8 381.5 328.9 86.2 Example 9 380.0 320.7 84.4 Example 10 381.1 319.7 83.9 Example 11 371.5 301.7 81.2 Example 12 374.8 325.0 86.7 Example 13 364.4 319.6 87.7 Comparative Example 1 322.6 274.9 85.2 Comparative Example 2 374.8 49.5 13.2 As shown in Table 1, the stress in Examples 1-3 is 385 kPa or higher, indicating that the asphalt material prepared in this application has good mechanical properties; the stress repair rate of the samples after curing in Examples 1-3 is above 91%, indicating that the asphalt material prepared in this application has good self-healing properties.

[0054] In Examples 4 and 5, the mass ratio of octaaminopropyl polysilsesquioxane to alumina during the preparation of the modified nanofiller was outside the range specified in this application. When the amount of octaaminopropyl polysilsesquioxane added was too small, the amount of octaaminopropyl polysilsesquioxane coating on the alumina surface was small, resulting in a thin shell thickness of the prepared modified nanofiller. This made it difficult to further improve the stability of the modified nanofiller, reduced the compatibility of the modified nanofiller in the system, and caused some agglomeration, affecting the overall stability of the system. When the amount of octaaminopropyl polysilsesquioxane added was too large, the shell thickness of octaaminopropyl polysilsesquioxane coating on the alumina surface was too large, resulting in a decrease in the particle size uniformity of the prepared modified nanofiller, which also affected the overall stability of the system. Therefore, the performance of Examples 4 and 5 was reduced.

[0055] In Example 6, when preparing the modified nanofiller, octaaminopropyl polysilsesquioxane was replaced with KH550. After modifying the alumina with KH550, the alumina was grafted with KH550. However, it was difficult to further coat the surface of the alumina and further reduce the surface energy of the alumina. As a result, the stability of the alumina in the system was difficult to decrease further, and the performance of Example 6 was reduced.

[0056] In Examples 7 and 8, the mass ratio of tetraethyl orthosilicate to ethyl cellulose during the preparation of self-healing microcapsules was not within the range specified in this application. When the content of ethyl cellulose was too low, the outer shell of the self-healing microcapsule was close to that of a silica shell, which reduced the sustained-release performance of the self-healing microcapsule and affected the self-healing effect of the system. When the content of ethyl cellulose was too high, the wall structure of the prepared self-healing microcapsule was too loose, which reduced the stability of the self-healing microcapsule and caused premature rupture, affecting the subsequent self-healing performance of the asphalt. Therefore, the performance of Examples 7 and 8 was reduced.

[0057] In Examples 9 and 10, the mass ratio of epoxy resin, ethyl cellulose, and silica during the preparation of self-healing microcapsules was not within the range specified in this application. When the silica content was too low, it was difficult to form a hybrid shell, resulting in a decrease in the coating performance of the epoxy resin and a decrease in the stability of the self-healing microcapsules. When the silica content was too high, it was difficult to further improve the crosslinking stability of the self-healing microcapsules, resulting in a decrease in the performance of the self-healing microcapsules and affecting the stability of the system and the subsequent repair effect on the system. Therefore, the performance of Examples 9 and 10 was reduced.

[0058] In Examples 11 and 12, the mass ratios of waterborne polyurethane, self-healing microcapsules, and modified nanofillers during the preparation of the polyurethane composites were not within the range specified in this application. When the content of self-healing microcapsules was too low, the distribution density of the self-healing microcapsules decreased, the epoxy resin penetration into the cracks decreased, and the healing performance was difficult to further improve, resulting in a decrease in the self-healing performance of the asphalt system. When the content of self-healing microcapsules was too high, the uniformity of the distribution of the self-healing microcapsules in the waterborne polyurethane system decreased, forming defects in the polyurethane composite, thereby reducing the stability of the system and decreasing the self-healing performance. Therefore, the performance of Examples 11 and 12 both decreased.

[0059] In Example 13, the modified nanofiller in the polyurethane composite was replaced with ordinary unmodified alumina. The unmodified alumina agglomerated in the system, and the compatibility of ordinary alumina in the system was difficult to improve further, resulting in a decrease in the stability of the system and affecting the overall performance of the system. Therefore, the performance of Example 13 was reduced.

[0060] In Comparative Example 1, no modified nanofiller was added, making it difficult to further improve the reinforcing properties of polyurethane. Therefore, the performance of the prepared asphalt material could not be further improved.

[0061] In Comparative Example 2, no self-healing microcapsules were added, making it difficult to further repair cracks in the asphalt, thus reducing the self-healing performance of the system.

[0062] This specific embodiment is merely an explanation of this application and is not intended to limit it. Based on the above description, those skilled in the art can make various changes and modifications without departing from the technical concept of this application. The technical scope of this application is not limited to the contents of the specification but must be determined according to the scope of the claims.

Claims

1. A self-healing intelligent asphalt pavement material, characterized in that: The components include the following mass fractions: 500-700 parts asphalt, 150-250 parts polyurethane composite, 80-120 parts water; The polyurethane composite comprises aqueous polyurethane, self-healing microcapsules, and modified nanofillers.

2. The self-healing intelligent asphalt pavement material according to claim 1, characterized in that: The self-healing microcapsule raw materials include tetraethyl orthosilicate, ethyl cellulose, silica, and epoxy resin.

3. The self-healing intelligent asphalt pavement material according to claim 2, characterized in that: The self-healing microcapsules were prepared using the following method: Hydrochloric acid and ethanol were mixed to obtain a hydrochloric acid alcohol solution. Ethyl acetate and tetraethyl orthosilicate were added to the hydrochloric acid alcohol solution, and the mixture was heated and stirred to obtain a silicon solution. Ethyl cellulose was added to the silicon solution, and after stirring, 3-(2-aminoethylamino)propyltriethoxysilane was added, followed by epoxy resin. After stirring, an oil phase was obtained. Sodium dodecylbenzenesulfonate and gum arabic were mixed and added to a saturated ethyl acetate solution. After mixing, an aqueous phase was obtained. The oil phase was added to the aqueous phase and emulsified to obtain an emulsion system. Nano-silica was mixed with water, ultrasonically dispersed, and then added to the emulsion system to obtain a mixture. The mixture was heated and stirred, cooled, filtered, washed, and dried to obtain self-healing microcapsules.

4. The self-healing intelligent asphalt pavement material according to claim 3, characterized in that: The mass ratio of ethyl cellulose to tetraethyl orthosilicate is 1:(1.2-1.4).

5. The self-healing intelligent asphalt pavement material according to claim 4, characterized in that: The mass ratio of the epoxy resin, ethyl cellulose and silica is 2:1:(0.03-0.05).

6. The self-healing intelligent asphalt pavement material according to claim 1, characterized in that: The modified nanofiller comprises octaaminopropyl polysilsesquioxane and alumina.

7. The self-healing intelligent asphalt pavement material according to claim 6, characterized in that: The modified nanofiller was prepared by the following method: Water, isopropanol and alumina were mixed and sonicated to obtain an alumina dispersion. Octaaminopropyl polysilsesquioxane was added to the alumina dispersion, heated and stirred, then centrifuged, washed and dried to obtain the modified nanofiller.

8. The self-healing intelligent asphalt pavement material according to claim 7, characterized in that: The mass ratio of the octaaminopropyl polysilsesquioxane to alumina is (5.2-5.6):

1.

9. The self-healing intelligent asphalt pavement material according to claim 1, characterized in that: The mass ratio of the aqueous polyurethane, self-healing microcapsules and modified nanofiller is 1:(0.12-0.14):0.

05.

10. A method for preparing a self-healing intelligent asphalt pavement material according to any one of claims 1-9, characterized in that: Includes the following steps: After mixing polyurethane composite, asphalt and water, a self-healing asphalt pavement material is obtained by stirring.