A modified asphalt composite material, preparation method and application thereof in ultra-thin wearing layer

Abstract

The present invention relates to the field of asphalt modification technology, and more particularly to a modified asphalt composite material, a preparation method and its application in ultra-thin wearing layer, including the following parts by mass of raw materials: 4 6 parts of SBS, 3 5 parts of LDPE, 3 5 parts of epoxy castor oil, 2 4 parts of octamercapto POSS modified wood fiber, 1 3 parts of antifreeze agent, 0.1 0.2 parts of mixed catalyst, 6 10 parts of modified asphalt, 5 8 parts of waste tire rubber powder, 100 parts of basalt wear-resistant aggregate; the antifreeze agent is mixed by (0.7 0.9) with AB modified mesoporous copper sulfide, ILs GO, and bisaldehyde PEG in a mass ratio of (0.2 0.3) : (1); the modified asphalt is mixed and kneaded by 10 parts of petroleum asphalt and 0.6 1.2 parts of tetraallylsilane. The modified asphalt composite material prepared by the present invention has good anti-freeze cracking performance, and has certain intrinsic self-repairing performance.

Description

Technical Field

[0001] The present invention relates to the technical field of asphalt modification and the technical field of ultra-thin wearing layers, and in particular to a modified asphalt composite material, a preparation method and application thereof in ultra-thin wearing layers. Background Art

[0002] An ultra-thin wearing layer is a 20±5mm thick, anti-skid and wear-resistant surface layer formed by paving and rolling an asphalt mixture on the road surface. It improves the road's anti-skid performance and smoothness, repairing minor rutting, cracking, whitening, and loosening, providing excellent preventive maintenance. However, existing ultra-thin wearing layers are prone to reflective cracking due to temperature stress and vehicle loads, which reduces the durability of the road surface. This is especially true in the harsh winter weather, when outdoor temperatures remain below 0°C for extended periods, making the surface prone to ice formation. Repeated freeze-thaw cycles can lead to freeze cracking in the ultra-thin wearing layer.

[0003] The existing technology generally improves the anti-icing and anti-crack performance by adding salt antifreeze agents or phase change materials to asphalt mixtures. For example, the invention patent with the announcement number CN112250813B discloses a temperature-sensitive antifreeze material for asphalt and concrete pavements and its preparation method. The antifreeze material is made of antifreeze ice core material and temperature-sensitive membrane material; the antifreeze ice core material is one or more of calcium chloride, sodium chloride, magnesium chloride, calcium acetate, magnesium acetate or potassium acetate; for example, the invention patent with the announcement number CN112160212B discloses an antifreeze asphalt pavement structure and a method for preparing the pavement material, including 2-6 parts by mass of a slow-release snow-melting agent, 4.7-6.5 parts by mass of an antifreeze-type SBS modified asphalt, wherein the slow-release snow-melting agent is composed of a porous non-metallic material, sodium chloride, magnesium chloride, and calcium oxide, and the antifreeze-type SBS asphalt is an SBS modified asphalt modified with an antifreeze agent; wherein the antifreeze agent is composed of ethylene glycol, glycerol, dimethyl silicone oil, and diatomaceous earth; as disclosed in the invention patent with the announcement number CN114524635B, a composite phase change material for asphalt pavement and its preparation method are disclosed, One or more of paraffin wax, polyethylene glycol, hydrated salts, fatty alcohols, and their derivatives are used as phase change material particles. For example, the invention patent with publication number CN113603398B discloses an anti-icing and noise-reducing asphalt mixture and its preparation method. By introducing a cement-based phase change material with paraffin wax as the core material, the modified asphalt's sensitivity to temperature is improved, thereby enhancing its anti-icing and anti-freeze cracking properties. For example, the invention patent with publication number CN112624668B discloses an anti-skid and anti-icing night-time visible asphalt pavement material, including a phase change material composed of polyethylene glycol and expanded graphite in a mass ratio of 1:6-7. This effectively improves the pavement's heat storage capacity and reduces the impact of ambient temperature on the pavement's temperature. The soluble salts in steel slag can also lower the freezing point of water. The addition of waste glass allows the glass to further reflect some sunlight to the asphalt pavement when the icy pavement is exposed to the sun, due to its excellent light transmission and reflection properties. This results in secondary illumination, fully utilizing the heat generated by the sunlight, and thus comprehensively improving the asphalt pavement's anti-icing ability.

[0004] However, salt-based antifreeze agents utilize the heat released by the dissolution of soluble salts and the low freezing point of salt water to achieve their anti-ice and snowmelt properties. Therefore, when the soluble salts are completely consumed, their antifreeze effect is lost. Simultaneously, the released soluble salt solution interacts with asphalt, significantly reducing the asphalt's adhesion and grip on the aggregate, thereby damaging the overall strength of the ultra-thin wearing layer and the pavement, and reducing wear resistance. Furthermore, both salt-based antifreeze agents and phase change materials achieve ice suppression and anti-icing properties through solid-liquid conversion, thereby improving the frost cracking resistance of asphalt mixtures and ultra-thin wearing layers. However, research on the application of photothermal conversion materials to asphalt mixtures to improve their anti-freeze and low-temperature cracking properties has not yet been reported in the literature or patents, and remains a research gap in the field of asphalt modification. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to propose a modified asphalt composite material, a preparation method and its application in ultra-thin wear layer. On the one hand, a new antifreeze agent that can be converted from light to heat is developed to improve the anti-freezing performance and low-temperature crack resistance of the modified asphalt composite material. On the other hand, through the scientific compounding of different materials, the low-temperature crack resistance of the modified asphalt composite material is improved.

[0006] Based on the above purpose, the present invention provides a modified asphalt composite material, comprising the following raw materials in parts by weight: 4-6 parts of SBS thermoplastic styrene-butadiene rubber, 3-5 parts of LDPE low-density polyethylene, 3-5 parts of epoxy castor oil, 2-4 parts of octamercapto POSS modified wood fiber, 1-3 parts of antifreeze agent, 0.1-0.2 parts of mixed catalyst, 6-10 parts of modified asphalt, 5-8 parts of waste tire rubber powder, and 100 parts of basalt wear-resistant aggregate;

[0007] The antifreeze agent is prepared by mixing azobenzene-modified mesoporous copper sulfide, ionic liquid-modified graphene, and dialdehyde-polyethylene glycol in a mass ratio of (0.7-0.9):(0.2-0.3):1;

[0008] The preparation method of the modified asphalt is as follows: heating 10 parts of petroleum asphalt to 150-160° C. by mass, adding 0.6-1.2 parts of tetraallylsilane, mixing and kneading for 3-5 minutes, and naturally cooling to obtain the modified asphalt.

[0009] Furthermore, the preparation method of the octa-mercapto POSS modified wood fiber comprises the following steps:

[0010] A1: Immerse wood fiber in a 0.5-2 wt% phytase aqueous solution at 45-55°C for 2-3 hours with stirring, then dropwise add tributylmethylammonium bis(trifluoromethanesulfonyl)imide salt, then stir and treat at 50-60°C for 0.5-1 hour, inactivate the enzyme at 95°C for 10 minutes, filter, and dry at 80°C to obtain pretreated wood fiber;

[0011] A2: Add 3-mercaptopropyltrimethoxysilane to a 70-80 wt% methanol solution, then dropwise add 36 wt% concentrated hydrochloric acid, and stir at 50-60°C for 3-5 hours to obtain an octamercapto POSS precursor solution;

[0012] A3: Add the pretreated wood fiber obtained in A1 to the octamercapto POSS precursor solution obtained in A2, stir and react at 55-65°C for 5-10 hours, let it stand at 25°C for 12 hours, filter, wash, and dry at 80°C to obtain octamercapto POSS modified wood fiber.

[0013] Furthermore, the mass ratio of the wood fiber, phytase aqueous solution, tributylmethylammonium bis(trifluoromethanesulfonyl)imide salt, 3-mercaptopropyltrimethoxysilane, methanol solution, and concentrated hydrochloric acid is 1:5:(0.2-0.3):(0.5-1):3:(0.01-0.015); and the length of the wood fiber is 2-4 mm and the diameter is 5-8 μm.

[0014] Furthermore, the preparation method of the azobenzene-modified mesoporous copper sulfide comprises the following steps:

[0015] B1: Add hollow mesoporous copper sulfide nanoparticles to a 50-60 wt% ethanol solution of crotonaldehyde and vinyltrimethoxysilane, ultrasonically disperse for 30 minutes, then add potassium persulfate, stir at 65-75°C for 1-3 hours, and stir at 60-70°C for 0.5-1 hour to obtain a formaldehyde-modified mesoporous copper sulfide dispersion.

[0016] B2: Add 4,4-diaminoazobenzene to the formaldehyde-modified mesoporous copper sulfide dispersion at 40-50°C, and carry out a Schiff base reaction under stirring for 5-8 hours. After filtration, washing, and vacuum drying, azobenzene-modified mesoporous copper sulfide is obtained.

[0017] Furthermore, the mass ratio of crotonaldehyde, vinyltrimethoxysilane, ethanol solution, hollow mesoporous copper sulfide nanoparticles, potassium persulfate, and 4,4'-diaminoazobenzene is (0.3-0.45):(0.2-0.3):10:1:(0.005-0.01):(0.5-0.7).

[0018] Furthermore, the preparation method of the ionic liquid modified graphene is: adding graphene oxide to anhydrous methanol, ultrasonically dispersing, adding 1-vinyl-3-ethylimidazole hexafluorophosphate, stirring and reacting at 30-40° C. for 1-3 hours, filtering, washing, and vacuum drying to obtain ionic liquid modified graphene.

[0019] Furthermore, the mass ratio of the graphene oxide, anhydrous methanol, and 1-vinyl-3-ethylimidazole hexafluorophosphate is 1:3:(0.3-0.5).

[0020] Furthermore, the mixed catalyst is prepared by mixing triethylamine, aluminum chloride, and dibenzoyl peroxide in a mass ratio of 1:(0.5-0.7):(0.8-1.1).

[0021] Furthermore, the basalt wear-resistant aggregate is graded by basalt fine material with a particle size between 0.075-4.75 mm and basalt coarse material with a particle size between 4.75-19 mm in a mass ratio of 1:(1-1.2).

[0022] The present invention also provides a preparation method of the modified asphalt composite material: the modified asphalt is heated to 160-175° C., SBS thermoplastic styrene-butadiene rubber, LDPE low-density polyethylene, waste tire rubber powder, and a mixed catalyst are added, mixed and stirred for 1-1.5 minutes, then cooled to 150-160° C., epoxy castor oil, octamercapto POSS modified wood fiber, antifreeze agent, and basalt wear-resistant aggregate are added in sequence, mixed and stirred for 2-3 minutes, and the modified asphalt composite material is obtained.

[0023] The present invention further provides application of the modified asphalt composite material in an ultra-thin wearing layer.

[0024] Beneficial effects of the present invention:

[0025] The present invention is the first to use crotonaldehyde and vinyltrimethoxysilane to modify hollow mesoporous copper sulfide nanoparticles to obtain formaldehyde-modified mesoporous copper sulfide, and further couple and graft 4,4-diaminoazobenzene through a Schiff base reaction to form a new type of photothermal conversion nanomaterial. The material can convert the solar energy stored by light into heat for release under low-temperature conditions, thereby achieving long-term sustainable anti-freezing and ice inhibition effects. At the same time, the combination of nano copper sulfide and diaminoazobenzene effectively expands the spectral absorption range and photothermal conversion efficiency, realizing dual conversion of near-infrared light and ultraviolet light, thereby improving the cold resistance and frost cracking resistance of asphalt composite materials.

[0026] The azobenzene-modified mesoporous copper sulfide synthesized in the present invention is further compounded with ionic liquid-modified graphene and bisaldehyde polyethylene glycol to prepare an antifreeze agent. The bisaldehyde polyethylene glycol serves as a phase change material, and the ionic liquid-modified graphene helps to improve the phase change temperature regulation performance. At the same time, the amino group in the structure of the azobenzene-modified mesoporous copper sulfide can react with the bisaldehyde polyethylene glycol to form a Schiff base bond. Due to the presence of a large number of aromatic Schiff base bonds in the antifreeze agent, dynamic reversible exchange can occur under heating conditions, thereby giving the modified asphalt composite material certain intrinsic self-repairing properties. At the same time, since the Schiff base compound has good antibacterial properties, the antibacterial properties of the composite material are improved. At the same time, the bisaldehyde polyethylene glycol can also undergo a cross-linking reaction with octamercapto POSS-modified wood fiber to form a dynamic reversible covalent bond, which also helps to improve the self-repair and self-healing properties of the modified asphalt composite material.

[0027] The present invention is the first to use tetraallylsilane to modify petroleum asphalt to prepare modified asphalt. In the composite material, the modified asphalt also improves the low-temperature crack resistance of the modified asphalt composite material to a certain extent. The reason may be that under the action of the catalyst, the modified asphalt reacts with octamercapto POSS modified wood fiber, SBS thermoplastic styrene-butadiene rubber, and epoxy castor oil, has a higher cross-linking density, and also improves the compatibility and bonding strength between different materials in the modified asphalt composite material, thereby further improving the low-temperature crack resistance. DETAILED DESCRIPTION

[0028] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to specific embodiments.

[0029] It should be noted that, unless otherwise defined, the technical or scientific terms used in the present invention should have the common meanings understood by persons having ordinary skills in the field to which the present invention belongs.

[0030] The preparation method of the hollow mesoporous copper sulfide nanoparticles selected in the following examples of the present invention is as follows: 31.5 g of CuSO4·5H2O is dissolved in 7 L of deionized water, and then 192.5 g of polyvinylpyrrolidone is added. After stirring at room temperature of 25°C for 20 minutes, 50 g of sodium hydroxide is added and stirred evenly. Then, 0.5 L of hydrazine hydrate is added and stirred for 15 minutes. Then, 63 g of Na2S·9H2O is added and stirred at 60°C for 1 hour. After centrifugation, washing, and freeze-drying, hollow mesoporous copper sulfide nanoparticles are obtained.

[0031] The present invention provides a modified asphalt composite material of an embodiment, comprising the following raw materials in parts by mass: 4-6 parts of SBS thermoplastic styrene-butadiene rubber, 3-5 parts of LDPE low-density polyethylene, 3-5 parts of epoxy castor oil, 2-4 parts of octamercapto POSS modified wood fiber, 1-3 parts of antifreeze agent, 0.1-0.2 parts of mixed catalyst, 6-10 parts of modified asphalt, 5-8 parts of waste tire rubber powder, and 100 parts of basalt wear-resistant aggregate.

[0032] The method for preparing the modified asphalt composite material of this embodiment comprises the following steps:

[0033] S1: Preparation of octamercapto POSS-modified wood fiber:

[0034] S10: Immerse wood fibers having a length of 2-4 mm and a diameter of 5-8 μm in a 0.5-2 wt% phytase aqueous solution, stir and immerse at 45-55° C. for 2-3 hours, then dropwise add tributylmethylammonium bis(trifluoromethanesulfonyl)imide salt, stir and immerse at 50-60° C. for 0.5-1 hour, inactivate the enzyme at 95° C. for 10 minutes, filter, and dry at 80° C. to obtain pretreated wood fibers;

[0035] S11: 3-mercaptopropyltrimethoxysilane was added to a 70-80 wt % methanol solution, and 36 wt % concentrated hydrochloric acid was added dropwise. The mixture was stirred at 50-60° C. for 3-5 h to obtain an octamercapto POSS precursor solution.

[0036] S12: adding the pretreated wood fiber obtained in S10 to the octamercapto POSS precursor solution obtained in S11, stirring and reacting at 55-65° C. for 5-10 h, standing and aging at 25° C. for 12 h, filtering, washing, and drying at 80° C. to obtain octamercapto POSS modified wood fiber;

[0037] The mass ratio of the wood fiber, phytase aqueous solution, tributylmethylammonium bis(trifluoromethanesulfonyl)imide salt, 3-mercaptopropyltrimethoxysilane, methanol solution, and concentrated hydrochloric acid is 1:5:(0.2-0.3):(0.5-1):3:(0.01-0.015);

[0038] S2: Preparation of antifreeze agent:

[0039] S20: Preparation of azobenzene-modified mesoporous copper sulfide:

[0040] S201: adding hollow mesoporous copper sulfide nanoparticles to a 50-60 wt% ethanol solution of crotonaldehyde and vinyltrimethoxysilane, ultrasonically dispersing for 30 minutes, then adding potassium persulfate, stirring at 65-75°C for 1-3 hours, and stirring at 60-70°C for 0.5-1 hour to obtain an aldehyde-modified mesoporous copper sulfide dispersion;

[0041] S202: adding 4,4-diaminoazobenzene to the aldehyde-modified mesoporous copper sulfide dispersion at 40-50° C., carrying out a Schiff base reaction under stirring for 5-8 hours, filtering, washing, and vacuum drying to obtain azobenzene-modified mesoporous copper sulfide (AB-modified mesoporous copper sulfide);

[0042] The mass ratio of the crotonaldehyde, vinyltrimethoxysilane, ethanol solution, hollow mesoporous copper sulfide nanoparticles, potassium persulfate, and 4,4'-diaminoazobenzene is (0.3-0.45):(0.2-0.3):10:1:(0.005-0.01):

[0043] (0.5-0.7);

[0044] S21: Preparation of ionic liquid modified graphene: Graphene oxide was added to anhydrous methanol, and after ultrasonic dispersion, 1-vinyl-3-ethylimidazolium hexafluorophosphate was added. The mixture was stirred at 30-40°C for 1-3 hours. After filtering, washing, and vacuum drying, ionic liquid modified graphene (ILs-GO) was obtained.

[0045] The mass ratio of the graphene oxide, anhydrous methanol, and 1-vinyl-3-ethylimidazole hexafluorophosphate is 1:3:(0.3-0.5);

[0046] S22: uniformly mixing azobenzene-modified mesoporous copper sulfide, ionic liquid-modified graphene, and bisaldehyde-polyethylene glycol in a mass ratio of (0.7-0.9):(0.2-0.3):1 to prepare an antifreeze agent;

[0047] S3: preparing a mixed catalyst: uniformly mixing triethylamine, aluminum chloride, and dibenzoyl peroxide in a mass ratio of 1:(0.5-0.7):(0.8-1.1) to obtain a mixed catalyst;

[0048] S4: preparing basalt wear-resistant aggregate: grading basalt fine material with a particle size of 0.075-4.75 mm and basalt coarse material with a particle size of 4.75-19 mm in a mass ratio of 1:(1-1.2) to obtain basalt wear-resistant aggregate;

[0049] S5: Preparation of modified asphalt: Heat 10 parts by mass of petroleum asphalt to 150-160°C, add 0.6-1.2 parts of tetraallylsilane, mix and knead for 3-5 minutes, and cool naturally to obtain modified asphalt;

[0050] S6: Preparation of modified asphalt composite material: Heat 6-10 parts of modified asphalt to 160-175°C by mass, then add 4-6 parts of SBS thermoplastic styrene-butadiene rubber, 3-5 parts of LDPE low-density polyethylene, 5-8 parts of waste tire rubber powder, and 0.1-0.2 parts of mixed catalyst, mix and stir for 1-1.5 minutes, then cool to 150-160°C, and then add 3-5 parts of epoxy castor oil, 2-4 parts of octamercapto POSS modified wood fiber, 1-3 parts of antifreeze agent, and 100 parts of basalt wear-resistant aggregate in sequence, mix and stir for 2-3 minutes to obtain the modified asphalt composite material.

[0051] Application of the modified asphalt composite material of this embodiment in an ultra-thin wearing layer.

[0052] Example 1

[0053] A method for preparing a modified asphalt composite material comprises the following steps:

[0054] S1: Preparation of octamercapto POSS-modified wood fiber:

[0055] S10: 10 g of wood fiber with a length of 2 mm and a diameter of 5 μm was immersed in 50 g of a 0.5 wt% phytase aqueous solution, stirred and immersed at 45° C. for 2 h, and then 2 g of tributylmethylammonium bis(trifluoromethanesulfonyl)imide was added dropwise. The mixture was stirred at 50° C. for 0.5 h, and the enzyme was inactivated at 95° C. for 10 min. The mixture was filtered and dried at 80° C. to obtain pretreated wood fiber.

[0056] S11: 5 g of 3-mercaptopropyltrimethoxysilane was added to 30 g of a 70 wt % methanol solution, and 0.1 g of 36 wt % concentrated hydrochloric acid was added dropwise. The mixture was stirred at 50° C. for 3 h to obtain an octamercapto POSS precursor solution.

[0057] S12: adding the pretreated wood fiber obtained in S10 to the octamercapto POSS precursor solution obtained in S11, stirring at 55° C. for 5 h, allowing to stand at 25° C. for 12 h, filtering, washing, and drying at 80° C. to obtain octamercapto POSS-modified wood fiber;

[0058] S2: Preparation of antifreeze agent:

[0059] S20: Preparation of azobenzene-modified mesoporous copper sulfide:

[0060] S201: 10 g of hollow mesoporous copper sulfide nanoparticles were added to 3 g of crotonaldehyde and 2 g of vinyltrimethoxysilane in 100 g of a 50 wt% ethanol solution, and ultrasonically dispersed for 30 min. 0.05 g of potassium persulfate was then added, and the mixture was stirred at 65° C. for 1 h, and then stirred at 60° C. for 0.5 h to obtain an aldehyde-modified mesoporous copper sulfide dispersion.

[0061] S202: At 40°C, 5 g of 4,4-diaminoazobenzene was added to the formaldehyde-modified mesoporous copper sulfide dispersion obtained in S201, and a Schiff base reaction was carried out under stirring for 5 hours. After filtering, washing, and vacuum drying, azobenzene-modified mesoporous copper sulfide was obtained.

[0062] S21: Preparation of ionic liquid modified graphene: 10 g of graphene oxide was added to 30 g of anhydrous methanol, and after ultrasonic dispersion, 3 g of 1-vinyl-3-ethylimidazolium hexafluorophosphate was added. The mixture was stirred at 30° C. for 1 h, filtered, washed, and vacuum dried to obtain ionic liquid modified graphene.

[0063] S22: uniformly mixing azobenzene-modified mesoporous copper sulfide, ionic liquid-modified graphene, and bisaldehyde-polyethylene glycol in a mass ratio of 0.7:0.2:1 to prepare an antifreeze agent;

[0064] S3: preparing a mixed catalyst: uniformly mixing triethylamine, aluminum chloride, and dibenzoyl peroxide in a mass ratio of 1:0.5:0.8 to obtain a mixed catalyst;

[0065] S4: preparing basalt wear-resistant aggregate: grading basalt fine material with a particle size of 0.075-4.75 mm and basalt coarse material with a particle size of 4.75-19 mm in a mass ratio of 1:1 to obtain basalt wear-resistant aggregate;

[0066] S5: Preparation of modified asphalt: Heat 10 parts by mass of petroleum asphalt to 150°C, add 0.6 parts of tetraallylsilane, mix and knead for 3 minutes, and cool naturally to obtain modified asphalt;

[0067] S6: Preparation of modified asphalt composite material: Heat 6 parts of modified asphalt to 160°C by mass, then add 4 parts of SBS thermoplastic styrene-butadiene rubber, 3 parts of LDPE low-density polyethylene, 5 parts of waste tire rubber powder, and 0.1 parts of mixed catalyst, mix and stir for 1 minute, then cool to 150°C, and then add 3 parts of epoxy castor oil, 2 parts of octamercapto POSS modified wood fiber, 1 part of antifreeze agent, and 100 parts of basalt wear-resistant aggregate in sequence, mix and stir for 2 minutes to obtain the modified asphalt composite material.

[0068] Example 2

[0069] A method for preparing a modified asphalt composite material comprises the following steps:

[0070] S1: Preparation of octamercapto POSS-modified wood fiber:

[0071] S10: 10 g of wood fiber with a length of 3 mm and a diameter of 6.5 μm was immersed in 50 g of a 1 wt% phytase aqueous solution, stirred at 50° C. for 2.5 h, and then 2.5 g of tributylmethylammonium bis(trifluoromethanesulfonyl)imide salt was added dropwise. The mixture was stirred at 55° C. for 1 h, and the enzyme was inactivated at 95° C. for 10 min. The mixture was filtered and dried at 80° C. to obtain pretreated wood fiber.

[0072] S11: 7.5 g of 3-mercaptopropyltrimethoxysilane was added to 30 g of a 70-80 wt % methanol solution, and 0.15 g of a 36 wt % concentrated hydrochloric acid was added dropwise. The mixture was stirred at 55° C. for 4 h to obtain an octamercapto POSS precursor solution.

[0073] S12: adding the pretreated wood fiber obtained in S10 to the octamercapto POSS precursor solution obtained in S11, stirring at 60° C. for 8 h, allowing to stand at 25° C. for 12 h, filtering, washing, and drying at 80° C. to obtain octamercapto POSS-modified wood fiber;

[0074] S2: Preparation of antifreeze agent:

[0075] S20: Preparation of azobenzene-modified mesoporous copper sulfide:

[0076] S201: 10 g of hollow mesoporous copper sulfide nanoparticles were added to 4 g of crotonaldehyde and 2.5 g of vinyltrimethoxysilane in 100 g of a 55 wt% ethanol solution, and ultrasonically dispersed for 30 min. 0.075 g of potassium persulfate was then added, and the mixture was stirred at 70° C. for 2 h and then at 65° C. for 1 h to obtain an aldehyde-modified mesoporous copper sulfide dispersion.

[0077] S202: At 45° C., 6 g of 4,4-diaminoazobenzene was added to the formaldehyde-modified mesoporous copper sulfide dispersion obtained in S201, and a Schiff base reaction was carried out under stirring for 6.5 h. After filtering, washing, and vacuum drying, azobenzene-modified mesoporous copper sulfide was obtained.

[0078] S21: Preparation of ionic liquid modified graphene: 10 g of graphene oxide was added to 30 g of anhydrous methanol, and after ultrasonic dispersion, 4 g of 1-vinyl-3-ethylimidazolium hexafluorophosphate was added. The mixture was stirred at 35° C. for 2 h, filtered, washed, and vacuum dried to obtain ionic liquid modified graphene.

[0079] S22: uniformly mixing azobenzene-modified mesoporous copper sulfide, ionic liquid-modified graphene, and bisaldehyde-polyethylene glycol in a mass ratio of 0.8:0.25:1 to prepare an antifreeze agent;

[0080] S3: preparing a mixed catalyst: uniformly mixing triethylamine, aluminum chloride, and dibenzoyl peroxide in a mass ratio of 1:0.6:1 to obtain a mixed catalyst;

[0081] S4: preparing basalt wear-resistant aggregate: grading basalt fine material with a particle size of 0.075-4.75 mm and basalt coarse material with a particle size of 4.75-19 mm in a mass ratio of 1:1.1 to obtain basalt wear-resistant aggregate;

[0082] S5: Preparation of modified asphalt: Heat 10 parts by mass of petroleum asphalt to 155°C, add 0.8 parts of tetraallylsilane, mix and knead for 4 minutes, and cool naturally to obtain modified asphalt;

[0083] S6: Preparation of modified asphalt composite material: heat 8 parts of modified asphalt to 170°C by mass, then add 5 parts of SBS thermoplastic styrene-butadiene rubber, 4 parts of LDPE low-density polyethylene, 6.5 parts of waste tire rubber powder, and 0.15 parts of mixed catalyst, mix and stir for 1.5 minutes, then cool to 155°C, and then add 4 parts of epoxy castor oil, 3 parts of octamercapto POSS modified wood fiber, 2 parts of antifreeze agent, and 100 parts of basalt wear-resistant aggregate in sequence, mix and stir for 2.5 minutes to obtain the modified asphalt composite material.

[0084] Example 3

[0085] A method for preparing a modified asphalt composite material comprises the following steps:

[0086] S1: Preparation of octamercapto POSS-modified wood fiber:

[0087] S10: 10 g of wood fiber with a length of 4 mm and a diameter of 8 μm was immersed in 50 g of a 2 wt% phytase aqueous solution, stirred and immersed at 55° C. for 3 h, and then 3 g of tributylmethylammonium bis(trifluoromethanesulfonyl)imide salt was added dropwise. The mixture was stirred at 60° C. for 1 h, and the enzyme was inactivated at 95° C. for 10 min. The mixture was filtered and dried at 80° C. to obtain pretreated wood fiber.

[0088] S11: 10 g of 3-mercaptopropyltrimethoxysilane was added to 30 g of 80 wt% methanol solution, and 0.15 g of 36 wt% concentrated hydrochloric acid was added dropwise. The mixture was stirred at 60° C. for 5 h to obtain an octamercapto POSS precursor solution.

[0089] S12: adding the pretreated wood fiber obtained in S10 to the octamercapto POSS precursor solution obtained in S11, stirring and reacting at 65° C. for 10 h, standing and aging at 25° C. for 12 h, filtering, washing, and drying at 80° C. to obtain octamercapto POSS modified wood fiber;

[0090] S2: Preparation of antifreeze agent:

[0091] S20: Preparation of azobenzene-modified mesoporous copper sulfide:

[0092] S201: 10 g of hollow mesoporous copper sulfide nanoparticles were added to 4.5 g of crotonaldehyde and 3 g of vinyltrimethoxysilane in 100 g of a 60 wt% ethanol solution, and ultrasonically dispersed for 30 min. 0.1 g of potassium persulfate was then added, and the mixture was stirred at 75° C. for 3 h, and then stirred at 70° C. for 1 h to obtain an aldehyde-modified mesoporous copper sulfide dispersion.

[0093] S202: At 50° C., 7 g of 4,4-diaminoazobenzene was added to the formaldehyde-modified mesoporous copper sulfide dispersion obtained in S201, and a Schiff base reaction was carried out under stirring for 8 h. After filtering, washing, and vacuum drying, azobenzene-modified mesoporous copper sulfide was obtained.

[0094] S21: Preparation of ionic liquid modified graphene: 10 g of graphene oxide was added to 30 g of anhydrous methanol, and after ultrasonic dispersion, 5 g of 1-vinyl-3-ethylimidazolium hexafluorophosphate was added. The mixture was stirred at 40° C. for 3 h, and filtered, washed, and vacuum dried to obtain ionic liquid modified graphene.

[0095] S22: uniformly mixing azobenzene-modified mesoporous copper sulfide, ionic liquid-modified graphene, and bisaldehyde-polyethylene glycol in a mass ratio of 0.9:0.3:1 to prepare an antifreeze agent;

[0096] S3: preparing a mixed catalyst: uniformly mixing triethylamine, aluminum chloride, and dibenzoyl peroxide in a mass ratio of 1:0.7:1.1 to obtain a mixed catalyst;

[0097] S4: preparing basalt wear-resistant aggregate: grading basalt fine material with a particle size of 0.075-4.75 mm and basalt coarse material with a particle size of 4.75-19 mm in a mass ratio of 1:1.2 to obtain basalt wear-resistant aggregate;

[0098] S5: Preparation of modified asphalt: Heat 10 parts by mass of petroleum asphalt to 160°C, add 1.2 parts of tetraallylsilane, mix and knead for 5 minutes, and cool naturally to obtain modified asphalt;

[0099] S6: Preparation of modified asphalt composite material: Heat 10 parts of modified asphalt to 175°C by mass, then add 6 parts of SBS thermoplastic styrene-butadiene rubber, 5 parts of LDPE low-density polyethylene, 8 parts of waste tire rubber powder, and 0.2 parts of mixed catalyst, mix and stir for 1.5 minutes, then cool to 160°C, and then add 5 parts of epoxy castor oil, 4 parts of octamercapto POSS modified wood fiber, 3 parts of antifreeze agent, and 100 parts of basalt wear-resistant aggregate in sequence, mix and stir for 3 minutes to obtain a modified asphalt composite material.

[0100] Comparative Example 1 is the same as Example 1, except that the antifreeze agent in Comparative Example 3 is prepared by mixing ionic liquid-modified graphene and dialdehyde polyethylene glycol in a mass ratio of 0.9:1.

[0101] Comparative Example 2 is the same as Example 1, except that the antifreeze agent in Comparative Example 4 is prepared by mixing azobenzene-modified mesoporous copper sulfide and dialdehyde-polyethylene glycol in a mass ratio of 0.9:1.

[0102] Comparative Example 3 is the same as Example 1, except that the antifreeze agent in Comparative Example 5 is prepared by mixing azobenzene-modified mesoporous copper sulfide, graphene oxide, and bisaldehyde polyethylene glycol in a mass ratio of 0.7:0.2:1.

[0103] Comparative Example 4 is the same as Example 1, except that the antifreeze agent in Comparative Example 6 is prepared by mixing azobenzene-modified mesoporous silica, ionic liquid-modified graphene oxide, and dialdehyde-polyethylene glycol in a mass ratio of 0.7:0.2:1; the preparation method of the azobenzene-modified mesoporous silica is as follows:

[0104] S201: 10 g of hollow mesoporous silica nanospheres were added to 3 g of crotonaldehyde and 2 g of vinyltrimethoxysilane in 100 g of a 50 wt% ethanol solution, and ultrasonically dispersed for 30 min. 0.05 g of potassium persulfate was then added, and the mixture was stirred at 65° C. for 1 h and then at 60° C. for 0.5 h to obtain an aldehyde-modified mesoporous silica dispersion.

[0105] S202: At 40° C., 5 g of 4,4-diaminoazobenzene was added to the formaldehyde-modified mesoporous silica dispersion obtained in S201, and a Schiff base reaction was carried out under stirring for 5 h. After filtering, washing, and vacuum drying, azobenzene-modified mesoporous silica was obtained.

[0106] Comparative Example 5 is the same as Example 1, except that the antifreeze agent in Comparative Example 7 is prepared by mixing hollow mesoporous copper sulfide nanoparticles, ionic liquid-modified graphene oxide, and dialdehyde polyethylene glycol in a mass ratio of 0.7:0.2:1.

[0107] Comparative Example 6 is the same as Example 1, except that no antifreeze agent is added during the preparation of the modified asphalt composite material.

[0108] According to the asphalt mixture specimen preparation method (wheel rolling method) T 0703-2011 in the Test Procedure for Asphalt and Asphalt Mixtures in Highway Engineering (JTG E20-2011), the modified asphalt composite materials of Examples 1-3 and Comparative Examples 1-6 were prepared into 300 mm × 300 mm × 50 mm Marshall specimens. Three groups of specimens were prepared for each test. The specimens were immersed in 0°C ice water for 5 minutes, then placed at -1°C, -5°C, and -10°C, respectively, and frozen for 6 hours under a 300W xenon lamp to simulate sunlight. The ice formation on the specimen surface was observed. The test results are shown in Table 1:

[0109] Table 1

[0110] experimental group -1℃ -5℃ -10℃ Example 1 Not frozen Not frozen Not frozen Example 2 Not frozen Not frozen Not frozen Example 3 Not frozen Not frozen Not frozen Comparative Example 1 Not frozen Soft ice Frozen Comparative Example 2 Not frozen Small smoothie Lots of smoothies Comparative Example 3 Not frozen Not frozen Small smoothie Comparative Example 4 Not frozen Lots of smoothies Soft ice Comparative Example 5 Not frozen Small smoothie Lots of smoothies Comparative Example 6 Frozen Frozen Frozen

[0111] As can be seen from Table 1, Examples 1-3 have excellent anti-freezing and anti-icing properties. The anti-freezing properties of Examples 1-3 are significantly improved by the combined use of azobenzene-modified mesoporous copper sulfide and ionic liquid-modified graphene. The selection of azobenzene-specific modified mesoporous copper sulfide has a key influence on the anti-freezing and anti-icing properties of the modified asphalt composite material. The reason is that 4,4-diaminoazobenzene is grafted and coupled on the surface of formaldehyde-modified mesoporous copper sulfide through a Schiff base reaction to form a new type of photothermal conversion nanomaterial, which can convert the solar energy stored by light into heat for release in a low-temperature environment, thereby achieving long-term sustainable anti-freezing and anti-icing effects. At the same time, the combination of nano-copper sulfide and diaminoazobenzene effectively expands the spectral absorption range and photothermal conversion efficiency, realizes the dual conversion of near-infrared light and ultraviolet light, and thus improves the cold resistance and anti-freezing properties of the asphalt composite material. At the same time, the modification of graphene by 1-vinyl-3-ethylimidazole hexafluorophosphate ionic liquid also has a certain effect on the antifreeze performance. The possible reason is that the use of vinyl ionic liquid to modify graphene can undergo cross-linking reactions with thiol, amino, vinyl, etc. in the composite system, and insert single graphene photothermal particles into the modified asphalt composite system, avoiding the agglomeration and phase separation problems of nanographene, constructing a three-dimensional grid structure for continuous photothermal conversion, and improving the photothermal conversion efficiency.

[0112] Comparative Example 7 is the same as Example 1, except that petroleum asphalt is used instead of the modified asphalt in Example 1.

[0113] Comparative Example 8 is the same as Example 1, except that the octamercapto POSS-modified wood fiber in Example 1 is replaced by wood fiber with a length of 2 mm and a diameter of 5 μm.

[0114] Comparative Example 9 is the same as Example 1, except that petroleum asphalt is used instead of the modified asphalt in Example 1, and wood fibers with a length of 2 mm and a diameter of 5 μm are used instead of the octamercapto POSS modified wood fibers in Example 1, and no antifreeze agent is added during the preparation of the modified asphalt composite material.

[0115] Under conditions of simulated sunlight using a 300W xenon lamp, the modified asphalt composite materials prepared in Examples 1-3 and Comparative Examples 1-10 were tested according to the freeze-thaw splitting test of asphalt mixtures T 0729-2000 in the Test Procedure for Asphalt and Asphalt Mixtures in Highway Engineering (JTGE20-2011). The test results are shown in Table 2:

[0116] Table 2

[0117]

[0118]

[0119] As shown in Table 2, the freeze-thaw splitting resistance of the modified asphalt composites prepared in Examples 1-3 is better than that of Comparative Examples 1-6, which further proves that azobenzene-modified mesoporous copper sulfide and ionic liquid-modified graphene synergistically improve the freeze-thaw splitting resistance of the modified asphalt composites; At the same time, compared with the unmodified petroleum asphalt matrix and unmodified wood fiber, tetraallylsilane-modified asphalt and octamercapto POSS-modified wood fiber also contribute to improving the freeze-thaw splitting resistance of the modified asphalt composite, and the two show a certain synergistic effect with the antifreeze agent. The reason for this may be that, under the action of a catalyst, the modified asphalt in Example 1 and the octamercapto POSS-modified wood fiber, SBS thermoplastic butadiene styrene The joint reaction of styrene rubber and epoxy castor oil has a higher cross-linking density, which also improves the compatibility and bonding strength between different materials in the modified asphalt composite material, thereby further improving the low-temperature crack resistance; at the same time, the octamercapto POSS modified wood fiber and the dialdehyde polyethylene glycol in the antifreeze agent can also undergo a cross-linking reaction to form a dynamically reversible covalent bond, which also helps to improve the self-repair and self-healing properties of the modified asphalt composite material; in addition, the dialdehyde polyethylene glycol can also react with the amino group in the azobenzene modified mesoporous copper sulfide structure to form a Schiff base bond. Due to the presence of a large number of dynamically reversible aromatic Schiff base bonds in the antifreeze agent, the modified asphalt composite material is further endowed with certain intrinsic self-repairing properties and the antibacterial properties of the composite material are also improved.

[0120] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present invention (including the claims) is limited to these examples. Within the scope of the present invention, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the present invention as described above, which are not provided in detail for the sake of simplicity.

[0121] The present invention is intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A modified asphalt composite material, characterized in that: The invention comprises the following raw materials in parts by weight: 4-6 parts of SBS thermoplastic styrene-butadiene rubber, 3-5 parts of LDPE low-density polyethylene, 3-5 parts of epoxy castor oil, 2-4 parts of octamercapto POSS modified wood fiber, 1-3 parts of antifreeze agent, 0.1-0.2 parts of mixed catalyst, 6-10 parts of modified asphalt, 5-8 parts of waste tire rubber powder, and 100 parts of basalt wear-resistant aggregate; The antifreeze agent is prepared by mixing azobenzene-modified mesoporous copper sulfide, ionic liquid-modified graphene, and dialdehyde-polyethylene glycol in a mass ratio of (0.7-0.9):(0.2-0.3):1; The modified asphalt is prepared by heating 10 parts by mass of petroleum asphalt to 150-160° C., adding 0.6-1.2 parts of tetraallylsilane, mixing and kneading for 3-5 minutes, and naturally cooling to obtain the modified asphalt. The preparation method of the octa-mercapto POSS modified wood fiber comprises the following steps: A1: Immerse wood fiber in a 0.5-2 wt% phytase aqueous solution at 45-55°C with stirring for 2-3 hours, then dropwise add tributylmethylammonium bis(trifluoromethanesulfonyl)imide salt, and then stir at 50-60°C for 0.5-1 hour. Inactivate the enzyme at 95°C for 10 minutes, filter, and dry at 80°C to obtain pretreated wood fiber. A2: Add 3-mercaptopropyltrimethoxysilane to a 70-80 wt% methanol solution, then dropwise add 36 wt% concentrated hydrochloric acid, and stir at 50-60°C for 3-5 hours to obtain an octamercapto POSS precursor solution; A3: Add the pretreated wood fiber obtained in A1 to the octamercapto POSS precursor solution obtained in A2, react with stirring at 55-65°C for 5-10 hours, allow to stand at 25°C for 12 hours, filter, wash, and dry at 80°C to obtain octamercapto POSS-modified wood fiber; The mass ratio of the wood fiber, phytase aqueous solution, tributylmethylammonium bis(trifluoromethanesulfonyl)imide salt, 3-mercaptopropyltrimethoxysilane, methanol solution, and concentrated hydrochloric acid is 1:5:(0.2-0.3):(0.5-1):3:(0.01-0.015); and the length of the wood fiber is 2-4 mm and the diameter is 5-8 μm; The preparation method of the azobenzene-modified mesoporous copper sulfide comprises the following steps: B1: Add hollow mesoporous copper sulfide nanoparticles to a 50-60wt% ethanol solution of crotonaldehyde and vinyltrimethoxysilane, ultrasonically disperse for 30 minutes, then add potassium persulfate, stir at 65-75°C for 1-3 hours, and stir at 60-70°C for 0.5-1 hour to obtain a formaldehyde-modified mesoporous copper sulfide dispersion. B2: Add 4,4-diaminoazobenzene to the formaldehyde-modified mesoporous copper sulfide dispersion at 40-50°C, and carry out a Schiff base reaction under stirring for 5-8 hours. After filtering, washing, and vacuum drying, azobenzene-modified mesoporous copper sulfide is obtained. The mass ratio of the crotonaldehyde, vinyltrimethoxysilane, ethanol solution, hollow mesoporous copper sulfide nanoparticles, potassium persulfate, and 4,4'-diaminoazobenzene is (0.3-0.45):(0.2-0.3):10:1:(0.005-0.01):(0.5-0.7); The mixed catalyst is prepared by mixing triethylamine, aluminum chloride and dibenzoyl peroxide in a mass ratio of 1:(0.5-0.7):(0.8-1.1).

2. The modified asphalt composite material according to claim 1, characterized in that: The preparation method of the ionic liquid modified graphene comprises: adding graphene oxide to anhydrous methanol, ultrasonically dispersing, adding 1-vinyl-3-ethylimidazolium hexafluorophosphate, stirring and reacting at 30-40° C. for 1-3 hours, filtering, washing, and vacuum drying to obtain the ionic liquid modified graphene.

3. The modified asphalt composite material according to claim 2, characterized in that: The mass ratio of the graphene oxide, anhydrous methanol and 1-vinyl-3-ethylimidazole hexafluorophosphate is 1:3:(0.3-0.5).

4. The modified asphalt composite material according to claim 1, characterized in that: The basalt wear-resistant aggregate is graded by basalt fine material with a particle size between 0.075-4.75 mm and basalt coarse material with a particle size between 4.75-19 mm in a mass ratio of 1:(1-1.2).

5. A method for preparing the modified asphalt composite material according to any one of claims 1 to 4, characterized in that: The modified asphalt is heated to 160-175°C, and then SBS thermoplastic styrene-butadiene rubber, LDPE low-density polyethylene, waste tire rubber powder, and a mixed catalyst are added, mixed and stirred for 1-1.5 minutes, and then cooled to 150-160°C, and then epoxy castor oil, octamercapto POSS modified wood fiber, antifreeze agent, and basalt wear-resistant aggregate are added in sequence, and mixed and stirred for 2-3 minutes to obtain a modified asphalt composite material.

6. Use of the modified asphalt composite material according to any one of claims 1 to 4 in an ultra-thin wearing layer.

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