High-temperature-resistant asphalt mixture additive and preparation method thereof

Abstract

The invention discloses a high-temperature-resistant asphalt mixture additive and a preparation method thereof. The high-temperature-resistant asphalt mixture additive comprises base asphalt and a modifier, the modifier is obtained by activating SiO2 particles through an activating agent, and the activating agent is a quaternary ammonium compound containing an epoxy functional group. The high-temperature-resistant asphalt mixture additive disclosed by the invention is used in an asphalt mixture mixing process, and can be quickly, uniformly and stably dispersed in an asphalt mixture, so that the high-temperature-resistant and rut-resistant properties of asphalt are improved.

Description

Technical Field

[0001] The present invention belongs to the field of asphalt modification, and particularly relates to an additive for high-temperature resistant modified asphalt mixture and a preparation method thereof. Background Art

[0002] Due to its good adhesion, ductility and deformability, asphalt is widely used in road paving, roof waterproofing, pipeline anti-corrosion and other fields. However, since asphalt itself is a thermoplastic material, it will produce irreversible plastic deformation when encountering high temperature, which limits its application scenarios. For example, when paving roads, rutting and other problems will occur in summer due to the high ground temperature. When used for roof waterproofing, it is easy to cause flowing or deformation.

[0003] Especially when paving roads, if the high-temperature resistance of asphalt is poor, it will directly affect the service life of the road. In order to obtain high-performance road asphalt, various modifiers such as polymers, rutting inhibitors, antioxidants, etc. are added to asphalt for modification. It is reported that active monomers are grafted onto polymers; polymers are functionalized with epoxy groups, acrylic acid, carboxylic acid, terminal amino groups, glycidyl methacrylate (GMA), maleic anhydride (MAH), etc.; polyurethane prepolymers react with asphalt side groups containing active groups (mainly -OH, usually present in asphaltenes) through free -NCO groups to modify asphalt. The chemically modified polyurethane asphalt has good anti-deformation, anti-aging, fatigue resistance and high-temperature storage properties, but its process is complex and the product properties are also unstable.

[0004] Nanomaterials have characteristics such as small size effect and surface effect, and can change the microstructure of asphalt, thereby improving its macroscopic properties. Among them, nano-sized SiO 2 has a large surface energy and excellent stability, and is one of the commonly used nanomaterials in asphalt modification. After adding nano-sized SiO 2 to asphalt, the rutting factor of asphalt will be improved, and the rheological aging index will also be reduced, indicating that the rutting resistance and anti-aging properties of asphalt are both improved. However, nano-SiO 2 is prone to agglomeration to form larger agglomerates, resulting in difficulty in exerting the nano effect. In addition, a large number of -Si-OH groups on the surface of nano-SiO 2 make it hydrophilic and lipophobic, with poor compatibility with asphalt, and it is difficult to be evenly dispersed in asphalt, weakening its improvement effect on asphalt.

[0005] At present, methods such as high-strength high-speed shear mixing have been used to improve its dispersion in asphalt, thereby enhancing the overall performance of asphalt. Compared with mechanical mixing, surface modification of nanoparticles can not only reduce the agglomeration between nanoparticles, but also enhance the interfacial interaction between the two through physical adsorption or chemical grafting, thus improving the performance of modified asphalt. Due to the inertness of the asphalt surface, the surface of nano-scale SiO 2 needs to be treated in order to chemically modify the asphalt. However, adding materials such as nano-SiO 2 to road asphalt can improve the high-temperature resistance and rutting resistance of asphalt, but reduces the ductility of asphalt, thus affecting the performance of asphalt. Summary of the Invention

[0006] To solve the existing problems, the present invention provides an anti-high-temperature asphalt mixture additive and a preparation method thereof. The anti-high-temperature asphalt mixture additive of the present invention can be rapidly, uniformly and stably dispersed in the asphalt mixture during the mixing process of the asphalt mixture, thereby improving the high-temperature resistance and rutting resistance of the asphalt.

[0007] In a first aspect of the present invention, there is provided an anti-high-temperature asphalt mixture additive, comprising: base asphalt and a modifier, wherein the modifier is obtained by activating SiO 2 particles with an activator, and the activator is a quaternary ammonium compound containing an epoxy group functional group.

[0008] Further, the activator contains the following structural formula:

[0009] Further, the activator is preferably at least one of epoxypropyl dodecyl dimethyl ammonium chloride and 2,3-epoxypropyl trimethyl ammonium chloride.

[0010] Further, the SiO 2 particles are nano-scale particles with a particle size of 50 nm to 200 nm.

[0011] Further, the asphaltene content of the base asphalt is 40 wt% to 80 wt%, and the softening point is 100 °C to 200 °C.

[0012] Further, the base asphalt is preferably obtained by mixing ethylene tar heavy fraction oil and hydrocracking unconverted oil and then performing an oxidation reaction followed by a polycondensation reaction. Among them, the ethylene tar heavy fraction oil is the heavy fraction after vacuum distillation to remove light components, and the distillation range is the fraction with >350 °C. The hydrocracking unconverted oil is derived from a conventional wax oil hydrocracking process, and the distillation range of the hydrocracking unconverted oil is the fraction with >400 °C. The ethylene tar heavy fraction oil accounts for 30% to 70% of the mass of the base asphalt, and the hydrocracking unconverted oil accounts for 30% to 70% of the mass of the base asphalt.

[0013] Furthermore, the dosage of the modifier is 1% - 10% of the mass of the base asphalt.

[0014] Furthermore, the particle size of the high-temperature resistant asphalt mixture additive is 10 - 80 mesh.

[0015] The second aspect of the present invention provides a preparation method of the above-mentioned high-temperature resistant asphalt mixture additive, including:

[0016] (a) Prepare the base asphalt and the modifier respectively;

[0017] (b) Add the obtained modifier into the molten base asphalt for mixing, carry out the reaction under stirring, cool down after the reaction ends, and pulverize to obtain the high-temperature resistant asphalt mixture additive.

[0018] Furthermore, in step (a), the preparation method of the base asphalt includes: mixing the ethylene tar heavy fraction oil and the hydrocracking unconverted oil, and then carrying out the oxidation and polycondensation reactions. Specifically, the ethylene tar heavy fraction oil and the hydrocracking unconverted oil are added into the reaction kettle according to a mass ratio of 3:7 - 7:3, heated to 250 - 300 °C, air is introduced, the reaction pressure is 0.2 - 1.0 MPa, and the reaction time is 20 - 90 min. Then the temperature is raised to 300 - 400 °C, inert gas is introduced, the reaction pressure is 1.0 - 2.0 MPa, and the reaction is carried out for 60 - 180 min to obtain the base asphalt.

[0019] Furthermore, in step (a), the preparation method of the modifier includes:

[0020] (1) Mix the SiO 2 particles, epoxy silane coupling agent and ethanol, heat under reflux, centrifuge the obtained suspension, ultrasonically disperse the precipitate with ethanol, remove the supernatant, wash, and dry to obtain an intermediate product;

[0021] (2) Dissolve the activator in ethanol, add it to the intermediate product obtained in step (1), stir and heat under reflux, centrifuge the obtained suspension, ultrasonically disperse the precipitate with deionized water, remove the supernatant, wash, and dry to obtain the modifier.

[0022] Furthermore, in step (1), the epoxy silane coupling agent is one or more of 3-glycidoxypropylmethyldiethoxysilane (GPTMS) and 3-glycidoxypropylmethyltriethoxysilane. The mass-volume ratio of the SiO 2 particles to the epoxy silane coupling agent is 1:1 - 3 g / mL; the SiO 2Particles, an epoxy - type silane coupling agent, and ethanol are mixed, where the volume ratio of the epoxy - type silane coupling agent to ethanol is 1∶1 - 5. The heating reflux time is 12 - 36 h, and the heating reflux temperature is 80 - 120 °C.

[0023] Further, in step (1), the rotation speed of centrifugal separation is 5000 - 15000 rpm, and the centrifugation time is 10 - 30 min. The frequency of ultrasonic dispersion is 20 kHz - 60 kHz, and the ultrasonic dispersion time is 5 - 20 min.

[0024] Further, in step (1), the drying time is 5 - 20 h, and the drying temperature is 50 - 80 °C.

[0025] Further, the ethanol in steps (1) and (2) is anhydrous ethanol.

[0026] Further, in step (2), based on the mass of ethanol, the addition amount of the activator is 1 wt% - 20 wt%. Based on the mass of ethanol, the addition amount of the intermediate product is 1 wt% - 30 wt%. Among them, the mass ratio of the addition amount of the activator to the intermediate product is 1∶1 - 2.

[0027] Further, in step (2), the rotation speed of centrifugal separation is 5000 - 15000 rpm, and the centrifugation time is 10 - 30 min. The frequency of ultrasonic dispersion is 20 kHz - 60 kHz, and the ultrasonic dispersion time is 5 - 20 min.

[0028] Further, in step (2), the heating reflux temperature is 80 - 120 °C, and the stirring reflux time is 12 - 36 h. The drying time is 5 - 20 h, and the drying temperature is 50 - 80 °C.

[0029] Further, in step (b), the melting temperature of the base asphalt is 150 - 250 °C.

[0030] Further, in step (b), the reaction temperature is 150 - 250 °C, and the reaction time is 1 - 10 h.

[0031] Further, in step (b), the cooling is to cool to - 20 °C - 0 °C.

[0032] The third aspect of the present invention provides an application of an anti - high - temperature asphalt mixture additive in road construction.

[0033] Further, the specific application is that first, the anti - high - temperature asphalt mixture additive is mixed with stone materials, and then mixed with road asphalt and mineral powder; it can also be that first, the road asphalt is mixed with stone materials, and then the above - mentioned anti - high - temperature asphalt mixture additive and mineral powder are added and mixed continuously to obtain an anti - high - temperature asphalt mixture for road construction.

[0034] Further, after batching according to the requirements of the stone material ratio, heat to 160 - 190 °C for dehumidification and heat preservation, and mix evenly; add the above high-temperature resistant asphalt mixture additive, and mix for 45 - 90 s; add road asphalt and mix for 30 - 90 s, add mineral powder and continue to mix for 30 - 60 s to obtain the high-temperature resistant asphalt mixture. This mixing process can also be to first add road asphalt, mix for 45 - 90 s, add the high-temperature resistant asphalt mixture additive and mix for 30 - 90 s, add mineral powder and continue to mix for 30 - 60 s.

[0035] Further, the addition amount of the high-temperature resistant asphalt mixture additive accounts for 5 wt% - 20 wt% of the mass of the road asphalt.

[0036] Compared with the prior art, the present invention has the following advantages:

[0037] (1) For the high-temperature resistant asphalt mixture additive of the present invention, a quaternary ammonium compound containing an epoxy functional group is used as an activator to activate the surface of nano-SiO 2 The base asphalt uses asphalt with a high asphaltene content, and its asphaltene can undergo a grafting reaction with the surface-activated SiO 2 This solves the problem that nano-SiO 2 is prone to agglomeration and difficult to disperse in asphalt.

[0038] (2) The modifier adopted by the present invention contains nano-SiO 2 and is rich in amine groups, which can not only improve the high-temperature resistance and rutting resistance performance, but also enable the additive to be dispersed into the asphalt mixture within a shorter mixing time, improving the overall performance of the mixture.

[0039] (3) The high-temperature resistant asphalt mixture additive obtained by treating nano-SiO 2 with an activator rich in amine groups and then reacting with the base asphalt can make the asphalt positively charged, while most of the stone materials used for paving roads are negatively charged. During the mixing process of the mixture, the asphalt can easily combine with the stone materials, increasing the adhesion and anti-stripping ability, and improving the overall service performance of the mixture. Specific Embodiments

[0040] The technical solutions of the present invention will be described in detail below in conjunction with embodiments, but the present invention is not limited to the following embodiments. In the present invention, wt% is the mass fraction.

[0041] First, the ethylene pyrolysis tar produced by Maoming Petrochemical Company was subjected to vacuum distillation to remove light components, obtaining a heavy fraction oil of ethylene tar with an initial boiling point > 350 °C, having an asphaltene mass content of 28.5% and a softening point of 92.6 °C. The following examples and comparative examples all used this heavy fraction oil of ethylene tar as the raw material. The hydrocracking unconverted oil was from the Hengli Petrochemical hydrocracking unit, being a fraction with an initial boiling point > 400 °C, having an asphaltene mass content of 12.8% and a softening point of 30.2 °C.

[0042] Example 1

[0043] 90 g of the heavy fraction oil of ethylene tar and 210 g of the hydrocracking unconverted oil were mixed and added to a reaction kettle, heated to 280 °C, air was introduced, the reaction pressure was 0.6 MPa, and the reaction time was 60 min. Then the temperature was raised to 340 °C, and N 2 was introduced, the reaction pressure was 1.5 MPa, and the reaction was carried out for 60 min to obtain the base asphalt, and its properties are shown in Table 1.

[0044] 25 g of SiO 2 (particle size 50 nm), 45 mL of 3-glycidoxypropylmethyldiethoxysilane, and 150 mL of ethanol were added to a flask, and the mixture was stirred and refluxed at 95 °C for 24 h. Then the suspension was centrifuged at 10000 rpm for 25 min to remove the supernatant; it was ultrasonically dispersed with 100 mL of ethanol for 15 min, the ultrasonic dispersion frequency was 20 kHz, the supernatant was removed, and the washing was repeated 3 times. The product was placed in an oven at 60 °C for 14 h to obtain the intermediate product.

[0045] 32 g of epoxypropyl dodecyl dimethyl ammonium chloride was added to 200 g of ethanol and dissolved, and then 38.5 g of the above-prepared intermediate product was added, and the mixture was stirred and refluxed at 105 °C for 20 h. Then the suspension was centrifuged at 10000 rpm for 20 min to remove the supernatant; it was ultrasonically dispersed with deionized water for 10 min, the ultrasonic dispersion frequency was 20 kHz, the supernatant was removed, and the washing was repeated 3 times. The product was placed in an oven at 65 °C for 10 h to obtain the modifier.

[0046] 300 g of the above-prepared base asphalt was heated to 185 °C, 18.8 g of the above-prepared modifier was added, and the mixture was stirred and mixed at 195 °C for reaction. The reaction time was 6 h. After the reaction, it was cooled to -10 °C and pulverized to obtain the high-temperature resistant asphalt mixture additive, and its properties are shown in Table 2.

[0047] Example 2

[0048] 120 g of the heavy fraction oil of ethylene tar and 180 g of the hydrocracking unconverted oil were mixed and added to a reaction kettle, heated to 270 °C, air was introduced, the reaction pressure was 0.8 MPa, and the reaction time was 75 min. Then the temperature was raised to 320 °C, and N2 At a reaction pressure of 1.6 MPa, the reaction was carried out for 100 min to obtain the base asphalt, and its properties are shown in Table 1.

[0049] Take 20 g of SiO 2 (with a particle size of 100 nm), 40 mL of 3-glycidoxypropyltrimethoxysilane and 140 mL of ethanol, add them to a flask, and stir and reflux the mixture at 105 °C for 30 h. Then centrifuge the suspension at 12000 rpm for 20 min to remove the supernatant; disperse it ultrasonically with 90 mL of ethanol for 10 min, the ultrasonic dispersion frequency is 40 kHz, remove the supernatant, repeat the washing 3 times, and put the product into an oven at 65 °C for 12 h to obtain the intermediate product.

[0050] Take 28 g of 2,3-epoxypropyltrimethylammonium chloride and dissolve it in 250 g of ethanol, then add 45.6 g of the intermediate product prepared above, and stir and reflux at 115 °C for 26 h. Then centrifuge the suspension at 11000 rpm for 25 min to remove the supernatant; disperse it ultrasonically with deionized water for 18 min, the ultrasonic dispersion frequency is 40 kHz, remove the supernatant, repeat the washing 3 times, and put the product into an oven at 70 °C for 12 h to obtain the modifier.

[0051] Heat 300 g of the base asphalt prepared above to 195 °C, add 15.6 g of the modifier prepared above, stir and mix at 210 °C for reaction, the reaction time is 7.5 h, after the reaction is completed, cool it to -15 °C and crush it to obtain the high-temperature resistant asphalt mixture additive, and its properties are shown in Table 2.

[0052] Example 3

[0053] Mix 150 g of ethylene tar heavy fraction oil and 150 g of hydrocracking unconverted oil and add them to a reaction kettle, heat to 285 °C, introduce air, the reaction pressure is 0.5 MPa, and the reaction time is 90 min. Then raise the temperature to 350 °C and introduce N 2 , the reaction pressure is 1.8 MPa, the reaction is carried out for 120 min to obtain the base asphalt, and its properties are shown in Table 1.

[0054] Take 28.6 g of SiO 2 (with a particle size of 150 nm), 65 mL of 3-glycidoxypropyltrimethoxysilane and 240 mL of ethanol, add them to a flask, and stir and reflux the mixture at 110 °C for 28 h. Then centrifuge the suspension at 14000 rpm for 25 min to remove the supernatant; disperse it ultrasonically with 140 mL of ethanol for 18 min, the ultrasonic dispersion frequency is 20 kHz, remove the supernatant, repeat the washing 3 times, and put the product into an oven at 75 °C for 8 h to obtain the intermediate product.

[0055] Dissolve 37.5 g of 2,3-epoxypropyltrimethylammonium chloride in 240 g of ethanol, then add 50.6 g of the intermediate product prepared above, and stir and reflux at 120 °C for 32 h. Then centrifuge the suspension at 13000 rpm for 18 min to remove the supernatant; disperse it ultrasonically with deionized water for 20 min, the frequency of ultrasonic dispersion is 40 kHz, remove the supernatant, repeat the washing 3 times, and place the product in an oven at 75 °C for 10 h to obtain the modifier.

[0056] Heat 300 g of the base asphalt prepared above to 200 °C, add 24.2 g of the modifier prepared above, stir and mix at 220 °C for reaction, the reaction time is 6 h, cool to -18 °C after the reaction, and pulverize to obtain the high-temperature resistant asphalt mixture additive, and its properties are shown in Table 2.

[0057] Example 4

[0058] Mix 175 g of ethylene tar heavy fraction oil and 125 g of hydrocracking unconverted oil, add them to a reaction kettle, heat to 290 °C, introduce air, the reaction pressure is 0.9 MPa, and the reaction time is 80 min. Then raise the temperature to 345 °C, introduce N 2 , the reaction pressure is 1.4 MPa, react for 150 min to obtain the base asphalt, and its properties are shown in Table 1.

[0059] Take 35.8 g of SiO 2 (particle size 200 nm), 80 mL of 3-glycidoxypropylmethyldiethoxysilane and 280 mL of ethanol, add them to a flask, and stir and reflux the mixture at 105 °C for 25 h. Then centrifuge the suspension at 13000 rpm for 28 min to remove the supernatant; disperse it ultrasonically with 160 mL of ethanol for 20 min, the frequency of ultrasonic dispersion is 40 kHz, remove the supernatant, repeat the washing 3 times, and place the product in an oven at 70 °C for 18 h to obtain the intermediate product.

[0060] Dissolve 45.5 g of epoxypropyl dodecyl dimethyl ammonium chloride in 250 g of ethanol, then add 55.8 g of the intermediate product prepared above, and stir and reflux at 100 °C for 35 h. Then centrifuge the suspension at 12000 rpm for 25 min to remove the supernatant; disperse it ultrasonically with deionized water for 15 min, the frequency of ultrasonic dispersion is 40 kHz, remove the supernatant, repeat the washing 3 times, and place the product in an oven at 70 °C for 16 h to obtain the modifier.

[0061] Heat 300 g of the base asphalt prepared above to 210 °C, add 21.5 g of the modifier prepared above, stir and mix at 230 °C for reaction, the reaction time is 8.5 h, cool to -16 °C after the reaction, and pulverize to obtain the high-temperature resistant asphalt mixture additive, and its properties are shown in Table 2.

[0062] Comparative Example 1

[0063] 150 g of ethylene tar heavy fraction oil and 150 g of hydrocracking unconverted oil were mixed and added to a reaction kettle, heated to 285 °C, air was introduced, the reaction pressure was 0.5 MPa, and the reaction time was 90 min. Then the temperature was raised to 350 °C, and N 2 was introduced, the reaction pressure was 1.8 MPa, and the reaction was carried out for 120 min to obtain base asphalt, and the properties are shown in Table 1.

[0064] 300 g of the base asphalt prepared above was heated to 200 °C, and 28.6 g of SiO 2 (with a particle size of 150 nm) was added and mixed and stirred at 220 °C for 6 h. After completion, it was cooled to -18 °C and pulverized to obtain a high-temperature resistant asphalt mixture additive.

[0065] Comparative Example 2

[0066] 28.6 g of SiO 2 (with a particle size of 150 nm), 65 mL of 3-glycidoxypropyltrimethoxysilane and 240 mL of ethanol were added to a flask, and the mixture was stirred and refluxed at 110 °C for 28 h. Then the suspension was centrifuged at 14000 rpm for 25 min to remove the supernatant; it was ultrasonically dispersed with 140 mL of ethanol for 18 min, the ultrasonic dispersion frequency was 20 kHz, the supernatant was removed, and the washing was repeated 3 times. The product was placed in an oven at 75 °C for 8 h to obtain an intermediate product.

[0067] 37.5 g of 2,3-epoxypropyltrimethylammonium chloride was added to 240 g of ethanol and dissolved, and then 50.6 g of the intermediate product prepared above was added, and the mixture was stirred and refluxed at 120 °C for 32 h. Then the suspension was centrifuged at 13000 rpm for 18 min to remove the supernatant; it was ultrasonically dispersed with deionized water for 20 min, the ultrasonic dispersion frequency was 40 kHz, the supernatant was removed, and the washing was repeated 3 times. The product was placed in an oven at 75 °C for 10 h to obtain a modifier.

[0068] 300 g of oxidized petroleum asphalt with a softening point of 145.2 °C was heated to 200 °C, 24.2 g of the modifier prepared above was added, and the mixture was stirred and mixed at 220 °C for reaction. The reaction time was 6 h. After the reaction was completed, it was cooled to -18 °C and pulverized to obtain a high-temperature resistant asphalt mixture additive.

[0069] Test Example

[0070] The high-temperature resistant asphalt mixture additives in the above-mentioned examples and comparative examples were respectively used to prepare asphalt mixtures for road and bridge. The preparation process is as follows: After proportioning the aggregate according to the AC-13 gradation requirements, it was heated to 185°C for dehumidification and insulation, and then evenly mixed; the above-mentioned high-temperature resistant asphalt mixture additive was added and mixed for 50 s; road asphalt was added and mixed for 60 s, and mineral powder was added and mixed for another 40 s to obtain the high-temperature resistant modified asphalt mixture, and the properties are shown in Table 3.

[0071] Among them, the road asphalt used was 70A asphalt produced by Sinopec, and the dosage was 4.6% of the total weight of the asphalt mixture; the dosage of the high-temperature resistant asphalt mixture additive was 0.55% of the total weight of the asphalt mixture, and the mixing temperature was 165°C. The mixed asphalt mixture was kept warm in an oven at 170°C, and then formed into Marshall specimens at a temperature of 165°C, and relevant performance tests of the asphalt mixture were carried out.

[0072] Table 1 Properties of base asphalt

[0073] Project Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Softening point, °C 139.6 134.8 145.2 151.7 145.2 145.2 Asphaltene, % 45.6 51.2 48.8 53.4 48.8 23.4

[0074] Table 2 Properties of high-temperature resistant asphalt mixture additive

[0075] Project Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Softening point, °C 148.5 145.6 155.4 157.8 148.6 149.4 Zeta potential / mV +15.8 +17.6 +16.8 +18.2 - +7.5 Particle size, mesh 60 40 80 40 80 80 Dispersibility Good Good Good Good Poor General

[0076] Table 3 Properties of asphalt mixtures in examples and comparative examples

[0077]

[0078] It should be emphasized that the above-mentioned content is only a specific embodiment of the present invention, and it cannot be determined that the present invention is limited to the above description in the specific implementation process. For those skilled in the technical field to which the present invention belongs, any simple deduction and improvement made without departing from the spirit and principle of the present invention shall be regarded as within the protection scope of the present invention.

Claims

1. A high-temperature resistant asphalt mixture additive, characterized in that: The additive includes: base asphalt and a modifier, and the modifier is obtained by activating SiO 2 particles with an activator, and the activator is a quaternary ammonium compound containing an epoxy group functional group.

2. The high-temperature resistant asphalt mixture additive according to claim 1, characterized in that: The activator contains the following structural formula:

3. The high-temperature resistant asphalt mixture additive according to claim 1 or 2, characterized in that: The activator is at least one of glycidyl dodecyldimethylammonium chloride and 2,3-epoxypropyltrimethylammonium chloride.

4. The high-temperature resistant asphalt mixture additive according to claim 1, characterized in that: The SiO 2 particles are nanoscale particles with a particle size of 50 nm to 200 nm.

5. The high-temperature resistant asphalt mixture additive according to claim 1, characterized in that: The asphaltene content of the base asphalt is 40wt% - 80wt%, and the softening point is 100°C - 200°C.

6. The high-temperature resistant asphalt mixture additive according to claim 1, characterized in that: The addition amount of the modifier is 1% - 10% of the mass of the base asphalt.

7. A preparation method of the high-temperature resistant asphalt mixture additive according to any one of claims 1 - 6, comprising: (a) Separately preparing the base asphalt and the modifier; (b) Adding the obtained modifier to the molten base asphalt for mixing, reacting under stirring, cooling after the reaction ends, and pulverizing to obtain the high-temperature resistant asphalt mixture additive.

8. The preparation method according to claim 7, characterized in that: In step (a), the preparation method of the base asphalt includes: mixing ethylene tar heavy fraction oil and hydrocracking unconverted oil, and then performing an oxidation reaction followed by a polycondensation reaction; specifically, adding ethylene tar heavy fraction oil and hydrocracking unconverted oil to the reaction kettle according to a mass ratio of 3:7 - 7:3, heating to 250 - 300°C, introducing air, with a reaction pressure of 0.2 - 1.0 MPa and a reaction time of 20 - 90 min; then raising the temperature to 300 - 400°C, introducing inert gas, with a reaction pressure of 1.0 - 2.0 MPa and reacting for 60 - 180 min to obtain the base asphalt.

9. The preparation method according to claim 7, characterized in that: In step (a), the preparation method of the modifier includes: (1) Mix SiO 2 particles, an epoxy-based silane coupling agent, and ethanol, heat under reflux, centrifuge the resulting suspension, ultrasonically disperse the precipitate with ethanol, remove the supernatant, wash, and dry to obtain an intermediate product; (2) Adding the activator to ethanol for dissolution, adding it to the intermediate product obtained in step (1), stirring and heating under reflux, centrifuging the obtained suspension, ultrasonically dispersing the precipitate with deionized water, removing the supernatant, washing, and drying to obtain the modifier.

10. The preparation method according to claim 9, characterized in that: In step (1), the epoxy - type silane coupling agent is one or more of 3 - glycidoxypropylmethyldiethoxysilane and 3 - glycidoxypropylmethyltriethoxysilane; the mass - volume ratio of the SiO 2 particles to the epoxy - type silane coupling agent is 1∶1 - 3 g / mL; the SiO 2 particles, the epoxy - type silane coupling agent and ethanol are mixed, wherein the volume ratio of the epoxy - type silane coupling agent to ethanol is 1∶1 - 5; the heating reflux time is 12 - 36 h, and the heating reflux temperature is 80 - 120 °C.

11. The preparation method according to claim 9, characterized in that: In step (1), the centrifugation speed is 5000 - 15000 rpm, and the centrifugation time is 10 - 30 min; the ultrasonic dispersion frequency is 20 kHz - 60 kHz, and the ultrasonic dispersion time is 5 - 20 min.

12. The preparation method according to claim 9, characterized in that: In step (2), based on the mass of ethanol, the addition amount of the activator is 1wt% - 20wt%; based on the mass of ethanol, the addition amount of the intermediate product is 1wt% - 30wt%; wherein, the mass ratio of the addition amounts of the activator and the intermediate product is 1:1 - 2.

13. The preparation method according to claim 9, It is characterized in that: In step (2), the rotation speed of centrifugal separation is 5000 - 15000 rpm, and the centrifugal time is 10 - 30 min; the frequency of ultrasonic dispersion is 20 kHz - 60 kHz, and the ultrasonic dispersion time is 5 - 20 min.

14. The preparation method according to claim 9, It is characterized in that: In step (2), the temperature of heating and refluxing is 80 - 120 °C, and the stirring and refluxing time is 12 - 36 h; the drying time is 5 - 20 h, and the drying temperature is 50 - 80 °C.

15. The preparation method according to claim 7, It is characterized in that: In step (b), the reaction temperature is 150 - 250 °C, and the reaction time is 1 - 10 h.

16. Application of an anti-high-temperature asphalt mixture additive according to any one of claims 1 - 6 or an anti-high-temperature asphalt mixture additive according to any one of claims 7 - 15 in road construction.

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