High-viscosity high-elasticity asphalt and preparation method thereof

Abstract

The invention discloses high-viscosity and high-elasticity asphalt and a preparation method thereof, and relates to the technical field of asphalt materials. The high-viscosity and high-elasticity asphalt is prepared from the following raw materials in parts by weight: 100 parts of matrix asphalt, 5 to 8 parts of a tackifier, 2 to 3 parts of nano montmorillonite, 1.5 to 3 parts of graphene oxide, 8 to 12 parts of modified SBS (Styrene Butadiene Styrene), 0.5 to 1.2 parts of an anti-aging agent and 0.1 to 0.3 part of a cross-linking agent. The high-viscosity and high-elasticity asphalt prepared by the preparation method disclosed by the invention has good elastic recovery rate and ageing resistance.

Description

Technical Field

[0001] The present invention relates to the technical field of asphalt materials, and particularly relates to a high-viscosity and high-elasticity asphalt and a preparation method thereof. Background Art

[0002] With the rapid development of modern transportation infrastructure, the performance requirements for road materials are getting higher and higher. Although traditional asphalt materials have been widely used in road construction, their performance limitations gradually emerge when facing complex working conditions and extreme environments. For example, ordinary asphalt is prone to softening in high-temperature environments, resulting in rutting on the road surface; it is also prone to embrittlement in low-temperature environments, causing cracking of the road surface. In addition, the adhesion and elasticity of ordinary asphalt are insufficient, making it difficult to meet the usage requirements under heavy traffic, frequent vibration, and complex climate conditions.

[0003] In recent years, in order to overcome the deficiencies of traditional asphalt, researchers have developed various modified asphalt technologies, such as adding polymers (such as SBS, EVA, etc.) to improve the viscoelastic properties of asphalt. However, there are still some problems with existing modified asphalt technologies: on the one hand, some modified asphalts perform poorly in terms of high-temperature stability or low-temperature toughness and cannot fully meet the actual engineering requirements; on the other hand, some modification methods are complex in process and high in cost, restricting their large-scale application.

[0004] In addition, with the improvement of environmental protection requirements, higher requirements are also put forward for the durability and anti-aging performance of asphalt materials. Traditional modified asphalt is prone to problems such as aging and peeling during long-term use, resulting in a decline in road surface performance and an increase in maintenance costs.

[0005] Chinese Patent Invention No. CN101560332A discloses a high-viscosity and high-elasticity asphalt and a preparation method thereof. The high-viscosity and high-elasticity asphalt is made of the following components: 50 - 92 parts by weight of asphalt matrix, 8 - 40 parts by mass of additive, and 0.1 - 12 parts by mass of cross-linking agent; the additive is rubber powder and styrene-butadiene-styrene block copolymer. This high-viscosity and high-elasticity asphalt has relatively excellent dynamic shear viscosity, but its anti-aging performance is poor. Therefore, developing an asphalt material with both high adhesion, high elasticity, and excellent durability has become a research hotspot in the current road material field. Summary of the Invention

[0006] Aiming at the deficiencies of the existing technology, the purpose of the present invention is to provide a high-viscosity and high-elasticity asphalt and a preparation method thereof.

[0007] To achieve the above purpose, the present invention is realized through the following technical solutions: A high-viscosity and high-elasticity asphalt, comprising the following raw materials in parts by weight: 100 parts of matrix asphalt, 5 - 8 parts of tackifier, 2 - 3 parts of nano - montmorillonite, 1.5 - 3 parts of graphene oxide, 8 - 12 parts of modified SBS, 0.5 - 1.2 parts of anti - aging agent, 0.1 - 0.3 parts of cross - linker; The modified SBS is prepared by the following method: S1: Under nitrogen protection, 1,3 - bis((2,2 - dimethyl - 1,3 - dioxolan - 4 - yl)methoxy)propan - 2 - amine reacts with methacryloyl chloride under the action of triethylamine to form an amide compound; S2: Under nitrogen protection, tetra - arm polyethylene glycol thiol reacts with the amide compound under the action of initiator AIBN to form an octa - arm cyclopentane compound, and the octa - arm cyclopentane compound is hydrolyzed to form an octa - arm hydroxy compound; S3: Under nitrogen protection, the octa - arm hydroxy compound reacts with SBS under the action of catalyst C - 94 and 1 - butyl - 3 - methylimidazolium methanesulfonate ionic liquid to obtain modified SBS.

[0008] In step S1, the feeding mass ratio of 1,3 - bis((2,2 - dimethyl - 1,3 - dioxolan - 4 - yl)methoxy)propan - 2 - amine to methacryloyl chloride is 3:(2 - 3).

[0009] In step S2, the feeding mass ratio of tetra - arm polyethylene glycol thiol to the amide compound is (6 - 8):4.

[0010] In step S3, the feeding mass ratio of the octa - arm hydroxy compound to SBS is 1:(30 - 40).

[0011] The anti - aging agent is prepared by the following method: A1: Oleic acid reacts under the action of formic acid and H2O2 to form an epoxide; A2: The epoxide reacts under the action of chromium acetylacetonate to form a polymer; A3: The polymer reacts with 3-(4-(4,6 - diphenyl - 1,3,5 - triazin - 2 - yl)-3 - hydroxyphenoxy)-2 - hydroxypropyl methacrylate to obtain the anti - aging agent.

[0012] In step A1, the feeding mass ratio of oleic acid to formic acid is 16:5.

[0013] In step A2, the feeding mass ratio of the epoxide to chromium acetylacetonate is 50:1.

[0014] In step A3, the feeding mass ratio of the polymer to 3-(4-(4,6 - diphenyl - 1,3,5 - triazin - 2 - yl)-3 - hydroxyphenoxy)-2 - hydroxypropyl methacrylate is 6:1.

[0015] The tackifier is hydrogenated rosin glyceride; the crosslinking agent is sulfur.

[0016] A preparation method of high-viscosity and high-elasticity asphalt includes the following steps: (1) Weigh by parts by weight: 100 parts of matrix asphalt, 5 - 8 parts of tackifier, 2 - 3 parts of nano-montmorillonite, 1.5 - 3 parts of graphene oxide, 8 - 12 parts of modified SBS, 0.5 - 1.2 parts of anti-aging agent, 0.1 - 0.3 parts of crosslinking agent; (2) Heat the matrix asphalt to 160 °C for melting, then add the tackifier, and shear at 2000 rpm for 20 min; cool down to 155 °C, add the modified SBS and anti-aging agent, and shear at 4000 rpm for 40 min; heat up to 175 °C, add the crosslinking agent, and react for 30 min; add the nano-montmorillonite and graphene oxide, and shear at 5000 rpm for 60 min; react at 160 °C for 2 h to obtain high-viscosity and high-elasticity asphalt.

[0017] Due to the above technical solutions, the beneficial effects of the present invention include: (1) The modified SBS prepared by the present invention significantly optimizes the elastic recovery performance of asphalt through the synergistic effects of a highly branched structure, polar groups to enhance compatibility, a dynamic hydrogen bond network, and flexible chain segments. This modified SBS not only improves the elastic recovery efficiency but also takes into account dispersibility and durability, and is suitable for high-demand pavement engineering scenarios.

[0018] (2) The 4,6-diphenyl-1,3,5-triazine group introduced by the anti-aging agent prepared by the present invention, as an efficient ultraviolet absorption group, can effectively capture ultraviolet rays through a conjugated system and a rigid planar structure, inhibiting the photo-oxidative degradation of asphalt; in addition, the molecular weight of the anti-aging agent is increased, making it have both excellent light stability effects and the advantages of resistance to migration and extraction. The synergistic effects of these characteristics can significantly improve the weather resistance, thermal-oxidative aging resistance, and low-temperature crack resistance of asphalt, and extend the service life of the road. Specific embodiments

[0019] The following is further illustrated with reference to embodiments, but the present invention is not limited to these embodiments.

[0020] Example 1 Preparation of modified SBS: S1: Under nitrogen protection, add 400 g of dichloromethane, 30 g of 1,3-bis((2,2-dimethyl-1,3-dioxolan-4-yl)methoxy)propan-2-amine, and 18 g of triethylamine to the reactor, stir and mix evenly. Under an ice bath, slowly add 20 g of methacryloyl chloride, dropwise add for 20 min, and after dropping, raise the temperature to room temperature. After reacting for 8 h, wash three times with saturated sodium chloride solution (200 ml each time), and carry out reduced pressure distillation at 35 °C for 2 h to obtain an amide compound; the reaction equation is shown as follows:

[0021] S2: Under nitrogen protection, add 800 g of DMSO, 60 g of tetra-arm polyethylene glycol mercapto group, 40 g of amide compound into the reactor, stir and mix evenly, heat up to 80 °C, then add 14 g of initiator AIBN, after reacting for 24 h, cool to room temperature, distill under reduced pressure at 60 °C for 3 h, and obtain octa-arm cyclopentane compound by silica gel column separation; add 400 g of deionized water and 80 g of octa-arm cyclopentane compound into the reactor, then add 100 g of 15 wt% dilute hydrochloric acid, stir and mix evenly, heat up to reflux and react for 2 h, add 10 wt% sodium hydroxide solution to adjust the pH to neutral, distill under reduced pressure at 60 °C for 3 h, and dry in vacuum at 60 °C for 5 h to obtain octa-arm hydroxyl compound; the reaction equation is shown as follows:

[0022] S3: Under nitrogen protection, add 1500 g of N,N-dimethylformamide, 10 g of octa-arm hydroxyl compound, 300 g of SBS, 20 g of catalyst C-94, 8 g of 1-butyl-3-methylimidazolium methanesulfonate ionic liquid into the reactor in sequence, heat up to 100 °C, after reacting for 5 h, cool to room temperature, add 2000 g of deionized water and stir evenly, centrifuge, wash with 500 g of absolute ethanol and then wash with 500 g of deionized water, dry in vacuum at 80 °C for 10 h to obtain modified SBS.

[0023] Example 2 Preparation of modified SBS: S1: Under nitrogen protection, add 400 g of dichloromethane, 30 g of 1,3-bis((2,2-dimethyl-1,3-dioxolan-4-yl)methoxy)propan-2-amine and 18 g of triethylamine into the reactor, stir and mix evenly, under ice bath, slowly add 25 g of methacryloyl chloride, dropwise add for 20 min, after dropping, raise the temperature to room temperature, after reacting for 6 h, wash with saturated sodium chloride solution three times (200 ml each time), distill under reduced pressure at 35 °C for 2 h to obtain amide compound; S2: Under nitrogen protection, add 800 g of DMSO, 70 g of tetra-arm polyethylene glycol mercapto group, 40 g of amide product into the reactor, stir and mix evenly, heat up to 90 °C, then add 14 g of initiator AIBN, after reacting for 22 h, cool to room temperature, distill under reduced pressure at 70 °C for 2 h, and obtain octa-arm cyclopentane compound by silica gel column separation; add 400 g of deionized water and 80 g of octa-arm cyclopentane compound into the reactor, then add 100 g of 15 wt% dilute hydrochloric acid, stir and mix evenly, heat up to reflux and react for 2 h, add 10 wt% sodium hydroxide solution to adjust the pH to neutral, distill under reduced pressure at 60 °C for 3 h, and dry in vacuum at 60 °C for 6 h to obtain octa-arm hydroxyl compound; S3: Under nitrogen protection, 1500 g of N,N-dimethylformamide, 10 g of octa-armed hydroxy compound, 350 g of SBS, 20 g of catalyst C-94, and 8 g of 1-butyl-3-methylimidazolium methanesulfonate ionic liquid were successively added to the reactor. The temperature was raised to 110 °C, and after reacting for 4 h, it was cooled to room temperature. 2000 g of deionized water was added and stirred evenly, centrifuged, washed with 500 g of absolute ethanol and then washed with 500 g of deionized water, and vacuum dried at 80 °C for 10 h to obtain modified SBS.

[0024] Example 3 Preparation of modified SBS: S1: Under nitrogen protection, 400 g of dichloromethane, 30 g of 1,3-bis((2,2-dimethyl-1,3-dioxolan-4-yl)methoxy)propan-2-amine, and 18 g of triethylamine were added to the reactor, stirred and mixed evenly. Under an ice bath, 30 g of methacryloyl chloride was slowly added dropwise over 20 min. After the addition, the temperature was raised to room temperature, and after reacting for 5 h, it was washed three times with saturated sodium chloride solution (200 ml each time), and distilled under reduced pressure at 35 °C for 2 h to obtain an amide compound; S2: Under nitrogen protection, 800 g of DMSO, 80 g of tetra-armed polyethylene glycol mercapto, and 40 g of amide product were added to the reactor, stirred and mixed evenly, the temperature was raised to 100 °C, and then 14 g of initiator AIBN was added. After reacting for 20 h, it was cooled to room temperature, and distilled under reduced pressure at 50 °C for 3 h. The octa-armed cyclopentane compound was obtained by silica column separation; 400 g of deionized water and 80 g of octa-armed cyclopentane compound were added to the reactor, and then 100 g of 15 wt% dilute hydrochloric acid was added, stirred and mixed evenly, the temperature was raised to reflux and reacted for 2 h, and then 10 wt% sodium hydroxide solution was added to adjust the pH to neutral, distilled under reduced pressure at 60 °C for 3 h, and vacuum dried at 70 °C for 5 h to obtain octa-armed hydroxy compound; S3: Under nitrogen protection, 1500 g of N,N-dimethylformamide, 10 g of octa-armed hydroxy compound, 400 g of SBS, 20 g of catalyst C-94, and 8 g of 1-butyl-3-methylimidazolium methanesulfonate ionic liquid were successively added to the reactor. The temperature was raised to 120 °C, and after reacting for 3 h, it was cooled to room temperature. 2000 g of deionized water was added and stirred evenly, centrifuged, washed with 500 g of absolute ethanol and then washed with 500 g of deionized water, and vacuum dried at 80 °C for 10 h to obtain modified SBS.

[0025] Example 4 Preparation of anti-aging agent: A1: Add 800 ml of DMF, 160 g of oleic acid, and 10 g of strong acid cation exchange resin into the reactor, stir and mix evenly, heat up to 50 °C, then mix 50 g of formic acid and 160 g of 30 wt% H2O2 solution evenly, slowly add the mixed solution of formic acid and H2O2 solution, dropwise add for 20 min, after reacting for 8 h, cool to room temperature, transfer the upper clear liquid to a separatory funnel, let it stand and then drain the lower inorganic liquid, and add deionized water for extraction three times (200 ml each time), distill under reduced pressure at 80 °C for 2 h to obtain an epoxide; the reaction equation is shown as follows:

[0026] A2: Add 500 g of epoxide and 10 g of chromium acetylacetonate into the reactor, stir, heat up to 170 °C and react for 5 h, then cool to room temperature, add 800 ml of methanol, stir, precipitate, filter, and dry in vacuum at 50 °C for 3 h to obtain a polymer; the reaction equation is shown as follows:

[0027] A3: Under nitrogen protection, add 300 g of N,N-dimethylformamide, 60 g of polymer, 10 g of 3-(4-(4,6-diphenyl-1,3,5-triazin-2-yl)-3-hydroxyphenoxy)-2-hydroxypropyl methacrylate, 4 g of catalyst C-94, and 2 g of 1-butyl-3-methylimidazolium methanesulfonate ionic liquid into the reactor in sequence, heat up to 100 °C, after reacting for 5 h, cool to room temperature, add 200 g of deionized water and stir evenly, centrifuge, wash with 100 g of absolute ethanol and then wash with 100 g of deionized water, dry in vacuum at 80 °C for 10 h to obtain an anti-aging agent. The reaction equation is shown as follows:

[0028] Example 5 Preparation of high-viscosity and high-elasticity asphalt: (1) Weigh: 1000 g of matrix asphalt, 50 g of tackifier (hydrogenated rosin glyceride), 20 g of nano-montmorillonite, 15 g of graphene oxide, 80 g of modified SBS (prepared in Example 1), 5 g of anti-aging agent (prepared in Example 4), and 1 g of crosslinking agent (sulfur); (2) Heat the matrix asphalt to 160 °C for melting, then add the tackifier, shear at 2000 rpm for 20 min; cool down to 155 °C, add the modified SBS and anti-aging agent, shear at 4000 rpm for 40 min; heat up to 175 °C, add the crosslinking agent, react for 30 min; add the nano-montmorillonite and graphene oxide, shear at 5000 rpm for 60 min; react at 160 °C for 2 h to obtain high-viscosity and high-elasticity asphalt.

[0029] Example 6 Preparation of high-viscosity and high-elasticity asphalt: (1) Weigh: 1000 g of matrix asphalt, 60 g of tackifier (hydrogenated rosin glyceride), 25 g of nano-montmorillonite, 25 g of graphene oxide, 100 g of modified SBS (prepared in Example 2), 8 g of anti-aging agent (prepared in Example 4), and 2 g of cross-linking agent (sulfur). (2) Heat the matrix asphalt to 160 °C until it melts, then add the tackifier and shear at 2000 rpm for 20 min; cool down to 155 °C, add the modified SBS and anti-aging agent, and shear at 4000 rpm for 40 min; heat up to 175 °C, add the cross-linking agent, and react for 30 min; add the nano-montmorillonite and graphene oxide, and shear at 5000 rpm for 60 min; react at 160 °C for 2 h to obtain high-viscosity and high-elasticity asphalt.

[0030] Example 7 Preparation of high-viscosity and high-elasticity asphalt: (1) Weigh: 1000 g of matrix asphalt, 80 g of tackifier (hydrogenated rosin glyceride), 30 g of nano-montmorillonite, 30 g of graphene oxide, 120 g of modified SBS (prepared in Example 3), 12 g of anti-aging agent (prepared in Example 4), and 3 g of cross-linking agent (sulfur). (2) Heat the matrix asphalt to 160 °C until it melts, then add the tackifier and shear at 2000 rpm for 20 min; cool down to 155 °C, add the modified SBS and anti-aging agent, and shear at 4000 rpm for 40 min; heat up to 175 °C, add the cross-linking agent, and react for 30 min; add the nano-montmorillonite and graphene oxide, and shear at 5000 rpm for 60 min; react at 160 °C for 2 h to obtain high-viscosity and high-elasticity asphalt.

[0031] Comparative Example 1 The raw material composition and process of the high-viscosity and high-elasticity asphalt are basically the same as those in Example 6, except that the modified SBS is replaced with an equal weight of modified SBS prepared by the following method: The preparation method of the modified SBS is basically the same as that in Example 2, except that 1,3-bis((2,2-dimethyl-1,3-dioxolan-4-yl)methoxy)propan-2-amine in step S1 is replaced with an equal weight of 2,2-dimethyl-1,3-dioxolane-4-methanamine.

[0032] Comparative Example 2 The raw material composition and process of the high-viscosity and high-elasticity asphalt are basically the same as those in Example 6, except that the modified SBS is replaced with an equal weight of modified SBS prepared by the following method: The preparation method of the modified SBS is basically the same as that in Example 2, except that the tetra-arm polyethylene glycol thiol in step S2 is replaced with an equal weight of pentaerythritol tetra(3-mercaptopropionate).

[0033] Comparative Example 3 The raw material composition and process of the high-viscosity and high-elasticity asphalt are basically the same as those in Example 6, except that the modified SBS is replaced with an equal weight of modified SBS prepared by the following method: The preparation method of the modified SBS is basically the same as that in Example 2, except that the tetra-arm polyethylene glycol mercapto group in step S2 is replaced with an equal weight of hexa-arm polyethylene glycol mercapto group.

[0034] Comparative Example 4 The raw material composition and process of the high-viscosity and high-elasticity asphalt are basically the same as those in Example 6, except that the modified SBS is replaced with an equal weight of modified SBS prepared by the following method: S1: Under nitrogen protection, add 800 g of DMSO, 70 g of tetra-arm polyethylene glycol mercapto group, 40 g of 2-hydroxyethyl methacrylate to the reactor, stir and mix evenly, heat up to 90 °C, then add 14 g of initiator AIBN, after reacting for 22 h, distill under reduced pressure at 70 °C for 2 h, and obtain intermediate 1 by silica gel column separation; S2: Under nitrogen protection, add 1500 g of N,N-dimethylformamide, 10 g of intermediate 1, 350 g of SBS, 20 g of catalyst C-94, 8 g of 1-butyl-3-methylimidazolium methanesulfonate ionic liquid to the reactor in sequence, heat up to 110 °C, after reacting for 4 h, cool to room temperature, add 2000 g of deionized water and stir evenly, centrifuge, wash with 300 g of absolute ethanol and then wash with 300 g of deionized water, and dry under vacuum at 80 °C for 10 h to obtain the modified SBS.

[0035] Comparative Example 5 The raw material composition and process of the high-viscosity and high-elasticity asphalt are basically the same as those in Example 6, except that the modified SBS is replaced with an equal weight of unmodified SBS.

[0036] Comparative Example 6 The raw material composition and process of the high-viscosity and high-elasticity asphalt are basically the same as those in Example 6, except that the anti-aging agent is replaced with an equal weight of anti-aging agent prepared by the following method: The preparation method of the anti-aging agent is basically the same as that in Example 4, except that the oleic acid in step A1 is replaced with an equal weight of 5-methylhexyl-2-butenoic acid.

[0037] Comparative Example 7 The raw material composition and process of the high-viscosity and high-elasticity asphalt are basically the same as those in Example 6, except that the anti-aging agent is replaced with an equal weight of anti-aging agent prepared by the following method: The preparation method of the anti-aging agent is basically the same as that of Example 4, except that 3-(4-(4,6-diphenyl-1,3,5-triazin-2-yl)-3-hydroxyphenoxy)-2-hydroxypropyl methacrylate in step A3 is replaced with 2-(2H-benzotriazol-2-yl)-4-methyl-6-(2-propenyl)phenol of equal weight.

[0038] Comparative Example 8 A high-viscosity and high-elasticity asphalt prepared by using the raw material composition and process of Example 2 of the Chinese invention patent with the publication number of CN101560332A.

[0039] The matrix asphalt used in the examples and comparative examples of this application is AH-70 road petroleum asphalt, produced by Liaohe Petrochemical Company, PetroChina; the nano-montmorillonite model is NANOLC-NP301, produced by Zhejiang Fenghong New Materials Co., Ltd.; the graphene oxide is SE3122 graphene oxide dispersion liquid (50wt%), produced by Changzhou Sixth Element Materials Technology Co., Ltd.; the hydrogenated rosin glyceride model is GEHR-85ER, produced by Hubei Shixing Chemical Co., Ltd.; the sulfur is the special sulfur powder of S-80 type produced by Qingdao Luchuan Chemical Co., Ltd., mesh number: 400 mesh; four-arm polyethylene glycol mercapto, molecular weight is 2000, model: 4-Arm PEG-SH; six-arm polyethylene glycol mercapto, molecular weight is 3000, model: 6-Arm PEG-SH; the SBS model is D-1155JOP, styrene content is 40%, molecular weight is 100000; the strong acid cation exchange resin is a polymer of divinylbenzene and sodium vinylbenzenesulfonate, trade name: Amberlite® IMAC HP1110 resin, produced by Sinopharm Chemical Reagent Co., Ltd.

[0040] The antioxidant test of the asphalt is carried out according to the standard in JTG E20-2011 for the rotating thin-film oven test (T 0610-2011), and the increment of the softening point (T 0606-2011) is used as the evaluation index of the antioxidant performance.

[0041] The elastic recovery rate test of the asphalt is carried out according to the method of T0662-2000 in JTG E20-2011.

[0042] The compressive strength test of the asphalt is carried out according to the method of T0713-2000 in JTG E20-2011. The asphalt composite material is made into a mixture and tested after standard curing for 10 days. The test results are shown in Table 1.

[0043] The asphalt mixture is prepared by the following method: heating the asphalt composite material prepared in the examples or comparative examples to 180 °C, mixing 200 g of the heated asphalt composite material with 300 g of fine aggregate and 600 g of coarse aggregate, and stirring for 30 min to obtain. Among them: the coarse aggregate is basalt gravel, with a particle size specification of 5-8 mm and an apparent relative density of 2.83; the fine aggregate is basalt manufactured sand, with a particle size specification of 1-2 mm and an apparent relative density of 2.75. Aging performance test: After the specimens are cured under standard conditions for 10 days, they are then placed in a forced ventilation oven, heated to 85 °C and irradiated with ultraviolet light using a 1000 W high-pressure mercury lamp for 5 days of long-term aging. After aging, they are naturally cooled to room temperature, and after standing for 5 h, the mechanical properties are tested.

[0044] Table 1 Asphalt Performance Index

[0045] It can be seen from Table 1 that the high-viscosity and high-elasticity asphalt prepared in Examples 5-7 of this application has excellent elastic recovery rate and anti-aging performance.

[0046] An octa-armed hydroxyl compound is introduced into the modified SBS prepared in the present invention. Its star-shaped topological structure significantly increases the degree of branching of SBS, forming a denser three-dimensional cross-linked network. This structure can effectively disperse stress and store more elastic potential energy, thereby improving the elastic recovery rate of asphalt. The flexibility of the polyethylene glycol segment endows the modified SBS with higher segmental mobility, making the asphalt more easily return to its original state after deformation. This flexibility helps to offset external stress and reduce permanent deformation. At the same time, the polyethylene glycol segment endows the modified SBS with amphiphilicity, which can not only be compatible with the hydrophobic components in the asphalt, but also form hydrogen bonds with the polar components through ether bonds, improving the dispersion uniformity of SBS in the asphalt. The uniformly dispersed SBS network can more effectively absorb and release stress, enhancing the elastic recovery rate. The amide bond introduced by methacryloyl chloride has high thermal stability, which can delay the aging process of asphalt at high temperatures and keep the elastic network effective for a long time. The introduced thioether bond has high chemical stability and can resist the erosion of moisture and oxygen in a humid and hot environment, improving the durability of asphalt.

[0047] The triazine ring in the prepared antioxidant is a UV absorbing group. Its conjugated structure and strong electron delocalization characteristics can efficiently absorb ultraviolet rays, convert light energy into harmless heat energy, and significantly inhibit the photo-oxidation reaction of asphalt caused by light. The phenyl substituent further enhances the light absorption range and stability of the triazine ring. The hydroxyl group in the molecule can act as a free radical scavenger, combining with the active free radicals generated during the oxidation process of asphalt, interrupting the chain oxidation reaction, and delaying the hardening and embrittlement process of asphalt. The polyester main chain formed by the polymerization of oleic acid epoxy compounds contains stable ester bonds and has a high thermal decomposition temperature. It can withstand the high temperature environment during asphalt processing and reduce thermal degradation. The long carbon chain of oleic acid gives the polymer main chain good flexibility, which can effectively disperse mechanical stress, reduce the extension of microcracks caused by the rigidity break of the molecular chain under repeated loads, and delay fatigue aging.

[0048] In comparative example 1, 2,2-dimethyl-1,3-dioxolane-4-methylamine contains only one 2,2-dimethyl-1,3-dioxolane ring. The single functional group causes the cross-linking reaction to generate only linear or low-branched structures. After hydrolysis, the number of hydroxyl groups decreases, and the grafting efficiency with SBS decreases. Finally, the modifier is difficult to effectively disperse and enhance the asphalt matrix.

[0049] In comparative example 2, pentaerythritol tetrakis(3-mercaptopropionic acid) ester lacks the spatial extensibility of the PEG chain segment, and the cross-linking sites are too concentrated, which easily causes local stress concentration and reduces the dynamic elastic recovery ability.

[0050] In comparative example 3, the six-arm structure of the six-arm polyethylene glycol thiol group has a higher degree of branching and dense cross-linking sites. When modified with SBS, it affects the uniformity of the grafting reaction, resulting in a partially dense or loose cross-linked network. This inhomogeneity can easily lead to stress concentration and reduce the deformation resistance of asphalt.

[0051] In comparative example 4, hydroxyethyl methacrylate can only form a linear or low-branched structure, resulting in a significant decrease in the cross-linking density. The weakening of the network structure reduces the elastic recovery rate of the asphalt.

[0052] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. However, any equivalent changes, modifications and evolutions made by ordinary technicians in the field without departing from the scope of the technical solution of the present invention by using the technical content disclosed above are all equivalent embodiments of the present invention. At the same time, any equivalent changes, modifications and evolutions made to the above embodiments based on the essential technology of the present invention are still within the protection scope of the technical solution of the present invention.

Claims

1. A high-viscosity and high-elastic asphalt, characterized in that: The invention comprises the following raw materials in parts by weight: 100 parts of base asphalt, 5-8 parts of tackifier, 2-3 parts of nano-montmorillonite, 1.5-3 parts of graphene oxide, 8-12 parts of modified SBS, 0.5-1.2 parts of anti-aging agent, 0.1-0.3 parts of cross-linking agent; The modified SBS is prepared by the following method: S1: Under nitrogen protection, 1,3-bis((2,2-dimethyl-1,3-dioxolan-4-yl)methoxy)propan-2-amine reacts with methacryloyl chloride under the action of triethylamine to form an amide compound; S2: Under nitrogen protection, the four-arm polyethylene glycol thiol group reacts with the amide compound under the action of the initiator AIBN to generate an eight-arm cyclopentane compound, and the eight-arm cyclopentane compound is hydrolyzed to generate an eight-arm hydroxy compound; S3: Under nitrogen protection, the eight-arm hydroxy compound reacts with SBS in the presence of catalyst C-94 and 1-butyl-3-methylimidazolium methane sulfonate ionic liquid to obtain modified SBS.

2. The high-viscosity and high-elastic asphalt according to claim 1, characterized in that: In the step S1, the mass ratio of 1,3-bis((2,2-dimethyl-1,3-dioxolan-4-yl)methoxy)propan-2-amine to methacryloyl chloride is 3:(2-3).

3. The high-viscosity and high-elastic asphalt according to claim 1, characterized in that: In the step S2, the mass ratio of the four-arm polyethylene glycol thiol group to the amide compound is (6-8):

4.

4. The high-viscosity and high-elastic asphalt according to claim 1, characterized in that: In the step S3, the feed mass ratio of the eight-arm hydroxy compound to SBS is 1:(30-40).

5. The high-viscosity and high-elastic asphalt according to claim 1, characterized in that: The anti-aging agent is prepared by the following method: A1: Oleic acid reacts with formic acid and H2O2 to form epoxy compounds; A2: Epoxides form polymers under the action of chromium acetylacetonate; A3: The polymer is reacted with 3-(4-(4,6-diphenyl-1,3,5-triazine-2-yl)-3-hydroxyphenoxy)-2-hydroxypropyl methacrylate to obtain an anti-aging agent.

6. The high-viscosity and high-elastic asphalt according to claim 5, characterized in that: In the step A1, the mass ratio of oleic acid to formic acid is 16:

5.

7. The high-viscosity and high-elastic asphalt according to claim 5, characterized in that: In the step A2, the mass ratio of the epoxy compound to chromium acetylacetonate is 50:

1.

8. The high-viscosity and high-elastic asphalt according to claim 5, characterized in that: In the step A3, the feed mass ratio of the polymer to 3-(4-(4,6-diphenyl-1,3,5-triazine-2-yl)-3-hydroxyphenoxy)-2-hydroxypropyl methacrylate is 6:

1.

9. The high-viscosity and high-elastic asphalt according to claim 1, characterized in that: The tackifier is hydrogenated rosin glycerol ester; the cross-linking agent is sulfur.

10. A method for preparing the high-viscosity and high-elastic asphalt according to any one of claims 1 to 9, characterized in that: The following steps are involved: (1) Weigh by weight: 100 parts of base asphalt, 5-8 parts of tackifier, 2-3 parts of nano-montmorillonite, 1.5-3 parts of graphene oxide, 8-12 parts of modified SBS, 0.5-1.2 parts of anti-aging agent, and 0.1-0.3 parts of cross-linking agent; (2) Heat the base asphalt to 160°C to melt, then add the viscosity enhancer and shear at 2000 rpm for 20 min; cool to 155°C, add the modified SBS and anti-aging agent, and shear at 4000 rpm for 40 min; heat to 175°C, add the cross-linking agent, and react for 30 min; add nano-montmorillonite and graphene oxide, and shear at 5000 rpm for 60 min; react at 160°C for 2 h to obtain a high-viscosity and high-elastic asphalt.

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