A high-performance modified asphalt specially used for highway pavement and its preparation method

Abstract

The invention discloses a high-performance modified asphalt specially used for highway pavement and a preparation method thereof. The asphalt comprises the following raw materials in parts by weight: 60-70 parts of petroleum asphalt, 15-25 parts of silicone resin, 15-25 parts of polyurethane resin, 5-10 parts of inorganic whiskers, 1-5 parts of antioxidant, 1.5-5.5 parts of UV absorber, 3-8 parts of modified nanofiller, and 1.5-8.5 parts of organic bentonite. The modified nanofiller preparation method comprises the following steps: first, adding thiourea and hydrated ammonium molybdate to a reactor, then adding distilled water, stirring at a speed of 500-600 r / min for 15-30 minutes, then hydrothermally heating the temperature to 150-160° C., stirring and reacting for 3-5 hours, cooling to room temperature, filtering, washing with water, and drying at 50-60° C. for 1-3 hours to obtain a nano-additive; then sequentially adding hexamethyldisiloxane, phenyltrimethoxysilane, the nano-additive, and concentrated sulfuric acid to the reactor, then heating to 65-75° C., stirring and reacting for 30-60 minutes, and then dropwise adding a nonionic surfactant while stirring, and completing the dropwise addition over 30-60 minutes; then reflux reaction for 1-2 hours, and drying to obtain the nano-additive.

Description

Technical Field

[0001] The present invention relates to the technical field of modified asphalt, and in particular to a high-performance modified asphalt specially used for highway pavement and a preparation method thereof. Background Art

[0002] Asphalt, a key material in highway construction, must demonstrate excellent economic and sustainable performance. The economic performance of highway asphalt requires providing a stable and durable pavement material while maintaining controllable costs to ensure safe and sustainable highway operations. Furthermore, the sustainability of highway asphalt is crucial, meeting environmental and sustainable development requirements to minimize negative environmental impacts. These requirements include, but are not limited to, low energy consumption, low pollution, and high recycling rates.

[0003] Asphalt possesses both viscous and elastic properties, manifesting in its fluidity and resistance to fluidity. At high temperatures, viscosity predominates, making asphalt easy to flow; at low temperatures, elasticity predominates, making asphalt resistant to fluidity. These characteristics manifest in asphalt-paved pavements, where rutting occurs under heavy loads in the hot summer, and thermal shrinkage cracks develop in the cold winter. This is particularly true for the large-span steel box girder bridges currently under construction across the country, placing even higher demands on the pavement's strength, deformation stability, and fatigue durability. Furthermore, specific performance requirements are placed on the pavement, including lightweight, high adhesion, and impermeability. As a crucial component of bridge systems, the quality of bridge deck pavement directly impacts driving safety, comfort, bridge durability, and the economic benefits of investment. Clearly, ordinary asphalt cannot meet these stringent performance requirements, necessitating the use of modified asphalt.

[0004] There are many methods for asphalt modification, most of which use polymer modification to change the natural properties of asphalt, that is, to improve the high-temperature rheological properties and low-temperature shrinkage cracking properties of asphalt. CN1364823 describes the production of rubber-modified asphalt materials using organic grafting materials and / or cross-linking components;

[0005] CN1415663A discloses a method of preparing a polymer-rich matrix using an aromatic-rich, wax-poor component and thermoplastic rubber, and preparing a uniformly dispersed asphalt composition using the matrix and base asphalt, and adding a composite additive accounting for 0.1-0.5% of the total asphalt amount to prepare a polymer-modified road asphalt product.

[0006] USP5348994 discloses a modified asphalt prepared from asphalt containing sulfonate or sulfonic acid groups, butyl rubber, SBS, sulfonated EPDM rubber, and a +1 to +3 valent cationic neutralizer. Pavements paved with this material have improved viscoelasticity, an increased softening point, and improved storage stability.

[0007] USP6399680 provides an asphalt component modified with a total amount of 0.02-3% sulfuric acid, phosphoric acid, glacial acetic acid and nitric acid as accelerators and a total amount of 0.2-15% epoxy group-containing copolymer;

[0008] USP5604274 discloses asphalt modified with a polymer containing epoxy groups at a total weight of 4-30% as component A, and asphalt modified with amines, anhydrides, alcohols, carboxylic acids, and thioureas as component B. A and B are mixed to form a paving material, wherein component A comprises 80-95% and component B comprises 5-20%. The polymer containing epoxy groups forms a continuous phase in the asphalt, thereby obtaining asphalt with thermosetting properties.

[0009] Generally speaking, polymer-modified asphalt is used both domestically and internationally. Domestically, this method primarily involves modifying asphalt with fillers and cross-linking materials, which helps improve the asphalt's operating temperature and elasticity. However, its compatibility is insufficient, resulting in insufficient toughness and low elongation, making it difficult to meet the requirements for highway paving. Furthermore, it requires on-site production, which can present challenges in quality control due to the variability of site conditions and varying worker quality. Therefore, the present invention provides a high-performance modified asphalt specifically for highway pavement and a method for its preparation. Summary of the Invention

[0010] In order to solve the problems mentioned in the above background technology, the present invention provides a high-performance modified asphalt specially used for highway pavement and a preparation method thereof.

[0011] In order to achieve the above object, the present invention adopts the following technical solutions:

[0012] A high-performance modified asphalt specially used for highway pavement, comprising the following raw materials in parts by weight:

[0013] 60-70 parts of petroleum asphalt, 15-25 parts of silicone resin, 15-25 parts of polyurethane resin, 5-10 parts of inorganic whiskers, 1-5 parts of antioxidant, 1.5-5.5 parts of UV absorber, 3-8 parts of modified nanofiller, and 1.5-8.5 parts of organic bentonite.

[0014] Preferably, the method for preparing the modified nanofiller comprises the following steps:

[0015] First, thiourea and hydrated ammonium molybdate are added to a reaction kettle, followed by distilled water, and the mixture is stirred at a speed of 500-600 r / min for 15-30 minutes. The mixture is then hydrothermally heated to a temperature of 150-160° C., stirred and reacted for 3-5 hours. After cooling to room temperature, the mixture is filtered, washed with water, and dried at 50-60° C. for 1-3 hours to obtain a nano-additive.

[0016] Hexamethyldisiloxane, phenyltrimethoxysilane, nano-additive and concentrated sulfuric acid are added to the reactor in sequence, and then heated to 65-75°C, stirred for reaction for 30-60 minutes, and then a non-ionic surfactant is added dropwise while stirring, and the addition is completed within 30-60 minutes; after reflux reaction for 1-2 hours, the product is dried.

[0017] Thiourea reacts with hydrated ammonium molybdate under hydrothermal conditions at 150-160°C. The Mo 6+ Restored to Mo 4+ , and with S 2- Combined to form MoS2 nanosheets;

[0018] The layered structure of MoS2 (strong covalent bonds within layers and weak van der Waals forces between layers) gives it high in-plane thermal conductivity, which can accelerate the heat dissipation of asphalt and reduce high-temperature rutting deformation; MoS2 nanosheets are embedded in the asphalt matrix through physical cross-linking to form a rigid skeleton, thereby improving shear strength.

[0019] During the silane hydrolysis and condensation process, hexamethyldisiloxane and phenyltrimethoxysilane are used to form a siloxane network under the catalysis of concentrated sulfuric acid. The addition of a nonionic surfactant helps disperse the nano-additives, preventing agglomeration and thus achieving uniform dispersion in the asphalt, improving the uniformity of the composite material. Furthermore, the introduction of phenyl groups may enhance compatibility with aromatic components in asphalt and improve interfacial bonding.

[0020] Preferably, the nonionic surfactant is one of 2-ethylhexanol, methyl phenylacetate, and diethyl phthalate.

[0021] The non-ionic surfactant is adsorbed on the surface of the nanofiller during the dropwise addition process, inhibiting the agglomeration of MoS2 nanosheets through the steric hindrance effect, ensuring their uniform dispersion in the asphalt, thereby maximizing the filler utilization.

[0022] Preferably, the petroleum asphalt is at least one of 90# petroleum asphalt, 100# petroleum asphalt, 110# petroleum asphalt, and 120# petroleum asphalt.

[0023] Preferably, the silicone resin includes at least one of methylphenyl silicone resin, methyl silicone resin, silicone resin emulsion, and high-temperature silicone resin.

[0024] Preferably, the inorganic whiskers are at least one of aluminum borate whiskers, potassium titanate whiskers, calcium sulfate whiskers, and zinc oxide whiskers.

[0025] Preferably, the antioxidant is at least one of antioxidant 1010, antioxidant 168, antioxidant 1076, and antioxidant 164.

[0026] Preferably, the UV absorber is at least one of 2-hydroxy-4-n-octyloxybenzophenone, 2-hydroxy-4-acryloyloxyethoxybenzophenone, and 2-(2-hydroxy-3,5-di-tert-butylphenyl)-5-chlorobenzotriazole.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] 1. The present invention can greatly improve the wear resistance and impact resistance of asphalt materials by replacing conventional fillers with the prepared modified nanofillers; the present invention can effectively enhance the interfacial bonding performance between nano-additives and polyurethane resins by introducing modified nanofillers, thereby effectively avoiding the problem that conventional fillers are difficult to disperse in asphalt materials, improving their reinforcement effect, and being more evenly distributed in the asphalt material. Since it can form a more stable microstructure, the asphalt material prepared can be more impact-resistant.

[0029] 2. The present invention optimizes the toughness of asphalt materials through the combined action of modified nanofillers and other ingredients, resulting in the resulting asphalt material exhibiting improved fracture resistance when subjected to impact. The synergistic effect between the various components of the modified nanofillers significantly improves the damping properties of the asphalt material, resulting in improved wear and impact resistance under dynamic loads. Furthermore, the synergistic effect of the MoS2 nanosheets and the siloxane coating significantly enhances the mechanical properties and durability of the asphalt through physical crosslinking and interface optimization. DETAILED DESCRIPTION

[0030] The following will clearly and completely describe the technical solutions of the present invention in conjunction with the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0031] Unless otherwise specified, the raw materials used in the present invention are all commercially available products. The polyurethane resin was purchased from Shanghai Qizhan New Material Technology Co., Ltd., model ML-1001P.

[0032] The organic bentonite was purchased from Sishui County Shengxin Refractory Materials Co., Ltd., model number 1524554.

[0033] Preparation Example 1: The preparation method of the modified nanofiller comprises the following steps:

[0034] S1. Add 100 g of thiourea and 80 g of hydrated ammonium molybdate to a reactor, then add 150 mL of distilled water, and stir at 500 rpm for 15 min.

[0035] S2, hydrothermally heating the mixture to 150°C, stirring and reacting for 3 hours, cooling to room temperature, filtering, washing with water, and drying at 50°C for 1 hour to obtain a nano-additive;

[0036] S3, 50g hexamethyldisiloxane, 45g phenyltrimethoxysilane, 100g nano-additive and 10mL concentrated sulfuric acid were added to the reactor in sequence, heated to 65°C, and stirred for reaction for 30min;

[0037] S4. Add 35 mL of nonionic surfactant 2-ethylhexanol dropwise while stirring for 30 minutes; reflux the mixture for 1 hour, and then dry to obtain the modified nanofiller.

[0038] Preparation Example 2: The preparation method of the modified nanofiller comprises the following steps:

[0039] S1. Add 100 g of thiourea and 80 g of hydrated ammonium molybdate to a reactor, then add 150 mL of distilled water, and stir at 550 r / min for 25 min.

[0040] S2, hydrothermally heating the temperature to 155°C, stirring and reacting for 4 hours, cooling to room temperature, filtering, washing with water, and drying at 55°C for 2 hours to obtain a nano-additive;

[0041] S3, 50g hexamethyldisiloxane, 45g phenyltrimethoxysilane, 100g nano-additive and 10mL concentrated sulfuric acid were added to the reactor in sequence, heated to 70°C, and stirred for 45min;

[0042] S4. Add 35 mL of nonionic surfactant methyl phenylacetate dropwise while stirring for 45 minutes; reflux for 2 hours, and then dry to obtain the modified nanofiller.

[0043] Preparation Example 3: The preparation method of the modified nanofiller comprises the following steps:

[0044] S1. Add 100 g of thiourea and 80 g of hydrated ammonium molybdate to a reactor, then add 150 mL of distilled water, and stir at 600 rpm for 30 min.

[0045] S2, hydrothermally heating the mixture to 160°C, stirring and reacting for 5 hours, cooling to room temperature, filtering, washing with water, and drying at 60°C for 3 hours to obtain a nano-additive;

[0046] S3, 50g hexamethyldisiloxane, 45g phenyltrimethoxysilane, 100g nano-additive and 10mL concentrated sulfuric acid were added to the reactor in sequence, heated to 75°C, and stirred for 60min;

[0047] S4. Add 35 mL of nonionic surfactant diethyl phthalate dropwise while stirring for 60 minutes; reflux for 2 hours and then dry to obtain the modified nanofiller.

[0048] Example 1:

[0049] A method for preparing high-performance modified asphalt specifically for highway pavement comprises the following steps:

[0050] Heat 60 g of 90# petroleum asphalt to 165° C., then add 15 g of methylphenyl silicone resin, 15 g of polyurethane resin, 5 g of aluminum borate whiskers, 1 g of antioxidant 1010, 1.5 g of 2-hydroxy-4-n-octyloxybenzophenone, 3 g of the modified nanofiller prepared in Preparation Example 1, and 1.5 g of organic bentonite and stir evenly to obtain the product.

[0051] Example 2:

[0052] A method for preparing high-performance modified asphalt specifically for highway pavement comprises the following steps:

[0053] Heat 65 g of 90# petroleum asphalt to 165° C., then add 20 g of methylphenyl silicone resin, 20 g of polyurethane resin, 8 g of aluminum borate whiskers, 3 g of antioxidant 1010, 3 g of 2-hydroxy-4-n-octyloxybenzophenone, 5 g of the modified nanofiller prepared in Preparation Example 1, and 5 g of organic bentonite and stir evenly to obtain the product.

[0054] Example 3:

[0055] A method for preparing high-performance modified asphalt specifically for highway pavement comprises the following steps:

[0056] Heat 70 g of 90# petroleum asphalt to 165° C., then add 25 g of methylphenyl silicone resin, 20 g of polyurethane resin, 10 g of aluminum borate whiskers, 5 g of antioxidant 1010, 5.5 g of 2-hydroxy-4-n-octyloxybenzophenone, 8 g of the modified nanofiller prepared in Preparation Example 1, and 8.5 g of organic bentonite and stir evenly to obtain the product.

[0057] Example 4:

[0058] A method for preparing high-performance modified asphalt specifically for highway pavement comprises the following steps:

[0059] Heat 60 g of 90# petroleum asphalt to 185°C, then add 15 g of methylphenyl silicone resin, 15 g of polyurethane resin, 5 g of aluminum borate whiskers, 1 g of antioxidant 1010, 1.5 g of 2-hydroxy-4-n-octyloxybenzophenone, 3 g of the modified nanofiller prepared in Preparation Example 2, and 1.5 g of organic bentonite and stir evenly to obtain the product.

[0060] Example 5:

[0061] A method for preparing high-performance modified asphalt specifically for highway pavement comprises the following steps:

[0062] Heat 60 g of 100# petroleum asphalt to 210° C., then add 15 g of methyl silicone resin, 15 g of polyurethane resin, 5 g of potassium titanate whiskers, 1 g of antioxidant 168, 1.5 g of 2-hydroxy-4-acryloyloxyethoxy benzophenone, 3 g of the modified nanofiller prepared in Preparation Example 2, and 1.5 g of organic bentonite and stir evenly to obtain the product.

[0063] Example 6:

[0064] A method for preparing high-performance modified asphalt specifically for highway pavement comprises the following steps:

[0065] Heat 65 g of 110# petroleum asphalt to 185° C., then add 20 g of silicone resin emulsion, 20 g of polyurethane resin, 8 g of calcium sulfate whiskers, 3 g of antioxidant 1010, 3 g of 2-hydroxy-4-n-octyloxybenzophenone, 5 g of the modified nanofiller prepared in Preparation Example 2, and 5 g of organic bentonite and stir evenly to obtain the product.

[0066] Example 7:

[0067] A method for preparing high-performance modified asphalt specifically for highway pavement comprises the following steps:

[0068] Heat 65 g of 110# petroleum asphalt to 210° C., then add 20 g of methylphenyl silicone resin, 20 g of polyurethane resin, 8 g of calcium sulfate whiskers, 3 g of antioxidant 1076, 3 g of 2-hydroxy-4-n-octyloxybenzophenone, 5 g of the modified nanofiller prepared in Preparation Example 3, and 5 g of organic bentonite and stir evenly to obtain the product.

[0069] Example 8:

[0070] A method for preparing high-performance modified asphalt specifically for highway pavement comprises the following steps:

[0071] Heat 70 g of 120# petroleum asphalt to 185° C., then add 25 g of methylphenyl silicone resin, 20 g of polyurethane resin, 10 g of zinc oxide whisker, 5 g of antioxidant 1010, 5.5 g of 2-hydroxy-4-n-octyloxybenzophenone, 8 g of the modified nanofiller prepared in Preparation Example 3, and 8.5 g of organic bentonite and stir evenly to obtain the product.

[0072] Example 9:

[0073] A method for preparing high-performance modified asphalt specifically for highway pavement comprises the following steps:

[0074] Heat 70 g of 90# petroleum asphalt to 200°C, then add 25 g of high-temperature silicone resin, 20 g of polyurethane resin, 10 g of aluminum borate whiskers, 5 g of antioxidant 164, 5.5 g of 2-(2-hydroxy-3,5-di-tert-butylphenyl)-5-chlorobenzotriazole, 8 g of the modified nanofiller prepared in Preparation Example 3, and 8.5 g of organic bentonite and stir evenly to obtain the product.

[0075] Comparative Example 1:

[0076] The difference between this comparative example and Example 1 is that no modified nanofiller is added.

[0077] Comparative Example 2:

[0078] The difference between this comparative example and Example 1 is that the modified nanofiller prepared in Preparation Example 1 is replaced by common commercially available slaked lime purchased from Jinan Ruishengyuan Chemical Co., Ltd.

[0079] Comparative Example 3:

[0080] The difference between this comparative example and Example 1 is that no nonionic surfactant is added during the preparation of the modified nanofiller in Preparation Example 1.

[0081] Wear resistance test: GB 1689-1998 was used as the experimental standard, and the mass loss of the sample was measured using an Akron wear tester.

[0082] Ductility: Based on GB / T0605-1993 as the experimental standard, the ductility of the test specimen at 5°C is tested (anti-deformation ability).

[0083] High temperature stability test: GB / T 0606-2000 was used as the experimental standard, and the ring and ball method was used to test the softening point of the sample.

[0084] The experimental steps are as follows: cast the sample in a circular ring with an inner diameter of 19mm, place a steel ball weighing 3.5g on the ring, use water as the medium, and heat at a rate of 5℃ / min. The sample gradually softens. Under the load of the steel ball, the temperature when the asphalt sinks to the specified distance (25.4mm) is recorded as the softening point.

[0085] 60℃ dynamic viscosity: the testing method is JTG E20 T0620, the technical requirement is ≥200000.

[0086] The performance test results of the products in Examples 1-9 and Comparative Examples 1-3 are shown in Table 1:

[0087] Table 1

[0088]

[0089] In summary, the synergistic effect of MoS2 nanosheets and the siloxane coating significantly improves the mechanical properties and durability of asphalt through physical crosslinking and interface optimization. The multi-stage composite of inorganic whiskers (micrometer-scale), resin networks (submicrometer-scale), and nanofillers (nanometer-scale) achieves a mechanical response that combines both rigidity and flexibility. Furthermore, the triple protection provided by chemical antioxidants, physical UV shielding, and a hydrophobic barrier systematically extends the service life of asphalt. Through multi-component synergistic optimization, this invention can meet the performance requirements of highway pavements in demanding environments such as high temperatures, heavy loads, and heavy rain, and has significant potential for engineering applications.

[0090] The high-performance modified asphalt obtained by the preparation method of the present application has various performance indicators that meet the relevant indicators of the "Test Procedure for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E20-2011), and its viscosity at 60°C meets the technical requirement of greater than 200,000 Pa·s, thereby effectively improving the adhesion, high-temperature stability, and fatigue durability of the asphalt pavement, effectively improving the tensile, shear, compressive and impact strengths, and improving its thermal stability and low-temperature resistance.

[0091] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A high-performance modified asphalt specially used for highway pavement, characterized in that: The raw materials include the following parts by weight: 60-70 parts of petroleum asphalt, 15-25 parts of silicone resin, 15-25 parts of polyurethane resin, 5-10 parts of inorganic whiskers, 1-5 parts of antioxidant, 1.5-5.5 parts of UV absorber, 3-8 parts of modified nanofiller, 1.5-8.5 parts of organic bentonite; The preparation method of the modified nanofiller comprises the following steps: S1. Add thiourea and hydrated ammonium molybdate to a reactor, then add distilled water, and stir at 500-600 rpm for 15-30 min. S2, hydrothermally heating the mixture to 150-160°C, stirring and reacting for 3-5 hours, cooling to room temperature, filtering, washing with water, and drying at 50-60°C for 1-3 hours to obtain a nano-additive; S3, add hexamethyldisiloxane, phenyltrimethoxysilane, nano additive and concentrated sulfuric acid to the reactor in sequence, heat to 65-75°C, and stir to react for 30-60 minutes; S4, adding a nonionic surfactant dropwise while stirring for 30-60 minutes; then refluxing for 1-2 hours, and drying to obtain a modified nanofiller; The nonionic surfactant is one of 2-ethylhexanol, methyl phenylacetate and diethyl phthalate.

2. The high-performance modified asphalt for highway pavement according to claim 1, characterized in that: The petroleum asphalt is at least one of 90# petroleum asphalt, 100# petroleum asphalt, 110# petroleum asphalt, and 120# petroleum asphalt.

3. The high-performance modified asphalt for highway pavement according to claim 1, characterized in that: The silicone resin includes at least one of methylphenyl silicone resin, methyl silicone resin, silicone resin emulsion, and high-temperature silicone resin.

4. The high-performance modified asphalt for highway pavement according to claim 1, characterized in that: The inorganic whiskers are at least one of aluminum borate whiskers, potassium titanate whiskers, calcium sulfate whiskers, and zinc oxide whiskers.

5. The high-performance modified asphalt for highway pavement according to claim 1, characterized in that: The antioxidant is at least one of antioxidant 1010, antioxidant 168, antioxidant 1076, and antioxidant 164.

6. The high-performance modified asphalt for highway pavement according to claim 1, characterized in that: The UV absorber is at least one of 2-hydroxy-4-n-octyloxybenzophenone, 2-hydroxy-4-acryloyloxyethoxybenzophenone, and 2-(2-hydroxy-3,5-di-tert-butylphenyl)-5-chlorobenzotriazole.

7. A method for preparing high-performance modified asphalt for highway pavement according to any one of claims 1 to 6, characterized in that: The following steps are involved: The raw materials in parts by weight are weighed, petroleum asphalt is heated to 165-210° C., and then silicone resin, polyurethane resin, inorganic whisker, antioxidant, UV absorber, modified nanofiller and organic bentonite are added and stirred evenly to obtain the product.

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