High-strength wear-resistant asphalt concrete and production process thereof

Abstract

The invention discloses high-strength wear-resistant asphalt concrete and a production process thereof, and relates to the field of asphalt concrete.The high-strength wear-resistant asphalt concrete is prepared from, by weight, 6-8 parts of modified asphalt, 45-55 parts of gravel, 25-30 parts of natural sand, 7-9 parts of mineral powder, 5-7 parts of steel slag powder and 0.4-0.8 part of modified microcapsules. The steel slag powder has the advantages of high strength, rough surface, wear resistance, firm combination with asphalt and the like, and meets the use requirements of high-strength wear-resistant asphalt concrete. The compatibility of the modified asphalt and the modified microcapsule is good. The modified asphalt is obtained by modifying asphalt by modified polypropylene into which a hindered phenol structure, a phosphite structure and an alcoholic hydroxyl group are introduced, so that the aging resistance and compressive strength of the concrete are improved. A wrapping material of the modified microcapsule contains DOPO and POSS structures, so that the flame retardance, the high temperature resistance and the self-healing capability of the concrete are improved.

Description

Technical Field

[0001] The invention relates to the field of asphalt concrete, and in particular to high-strength wear-resistant asphalt concrete and a production process thereof. Background Art

[0002] Asphalt concrete is different from ordinary concrete which uses cement as the cementing material. It uses asphalt as the cementing material, combined with coarse aggregate, fine aggregate and admixtures, and is mixed and prepared as a concrete material. It is widely used in road paving. The use of admixtures such as microcapsules and polymers can enhance the durability, crack resistance and anti-aging properties of concrete.

[0003] The patent with announcement number CN106810102B discloses a self-healing microcapsule for cracks in asphalt concrete and its preparation method. The microcapsules of this invention can significantly enhance the self-healing ability of asphalt concrete and extend the service life of asphalt pavement. However, there are still the following shortcomings: the wrapping material of the synthesized microcapsules is made of raw materials such as epoxy resin, curing agent, diluent and dispersant. The high temperature resistance of epoxy resin itself is insufficient, and it does not have flame retardant properties and has poor compatibility with asphalt. Asphalt concrete is usually used in asphalt pavement. Under the influence of high temperature, there is a possibility of fire. Therefore, the wrapping material used in the microcapsules of this invention is limited in use in asphalt concrete. Studies have shown that sunflower oil, as a regeneration agent, can significantly improve the healing ability of concrete. How to use it in asphalt concrete to improve the self-healing ability of asphalt concrete is worthy of in-depth study.

[0004] Previous studies using polypropylene modified asphalt have shown that polypropylene has good dispersibility with asphalt and can improve the penetration and softening point of asphalt. However, the molecular chain of polypropylene has a small polarity and is not compatible with microcapsules wrapped with epoxy resin, which is not conducive to the use of polypropylene modified asphalt and epoxy resin to improve the performance of asphalt concrete. In addition, during the use of asphalt concrete in asphalt pavement, it is inevitably affected by light, heat, oxygen, etc. Polypropylene, epoxy resin and asphalt will age and degrade, thereby reducing the performance of asphalt concrete and shortening its service life.

[0005] Therefore, a suitable modification method is needed to solve the problem that the above-mentioned epoxy resin-wrapped microcapsules have poor compatibility with polypropylene-modified asphalt, so as to improve the comprehensive performance of the prepared asphalt concrete. Summary of the invention

[0006] In order to solve the above technical problems, the present invention provides a high-strength wear-resistant asphalt concrete and a production process thereof.

[0007] The purpose of the present invention can be achieved through the following technical solutions:

[0008] A high-strength wear-resistant asphalt concrete comprises the following raw materials in parts by weight: 6-8 parts of modified asphalt, 45-55 parts of crushed stone, 25-30 parts of natural sand, 7-9 parts of mineral powder, 5-7 parts of steel slag powder and 0.4-0.8 parts of modified microcapsules;

[0009] The production process of the high-strength wear-resistant asphalt concrete comprises the following steps:

[0010] Crushed stone, natural sand and steel slag powder are stirred and heated at 160-170°C for 30 minutes to obtain a preheated mixture, and then the modified asphalt is heated to 150-160°C and added to the mixture, and then the modified microcapsules are added and stirred for 2-3 minutes, and then the mineral powder is added and stirred for another 2-3 minutes to obtain high-strength wear-resistant asphalt concrete.

[0011] The modified asphalt is prepared by the following steps:

[0012] Step A1: Add undecene bromide to dichloromethane, start stirring, then add 3-chloroperoxybenzoic acid, stir and react at room temperature for 4-5 hours to obtain an epoxy product; in a nitrogen atmosphere, add 3,5-di-tert-butyl-4-hydroxyphenylacetic acid and toluene to a flask, heat to 45°C, add pyridine, start stirring, add the epoxy product to the flask, stir and react for 8-10 hours, then heat to 110-120°C, stir for 1-2 hours to obtain a hydroxyl product;

[0013] Further, the ratio of undecene bromide, dichloromethane and 3-chloroperoxybenzoic acid is 0.1 mol: 120-130 mL: 0.1 mol; the ratio of 3,5-di-tert-butyl-4-hydroxyphenylacetic acid, toluene, pyridine and epoxidation product is 0.1 mol: 180-190 mL: 0.010-0.015 mol: 0.1 mol;

[0014] During the reaction of step A1, the carbon-carbon double bond of undecene bromide is oxidized to an epoxy group to obtain an epoxy product; the carboxyl group of 3,5-di-tert-butyl-4-hydroxyphenylacetic acid reacts with the epoxy group of the epoxy product to form a hydroxyl product containing a hindered phenol;

[0015] Step A2: adding the hydroxyl product to toluene, stirring for 5-10 minutes to obtain a toluene solution of the hydroxyl product, adding diethylphosphite chloride and triethylamine to a flask, slowly dropping the toluene solution of the hydroxyl product into the flask at 40°C, stirring at a constant temperature for 1 hour, raising the temperature to 60°C, stirring at a constant temperature for 5-6 hours, filtering, and distilling under reduced pressure to obtain a bromoalkane; adding p-nitrobenzyl alcohol to toluene, adding the bromoalkane and sodium hydroxide under stirring, and reacting at 40°C with stirring for 4-5 hours to obtain an etherification product;

[0016] Further, the dosage ratio of the hydroxyl product and toluene is 0.1 mol: 185-195 mL; the dosage ratio of diethylphosphite chloride, triethylamine, and toluene solution of the hydroxyl product is 16.5-17.5 g: 20-25 mL: 195-205 mL; the dosage ratio of p-nitrobenzyl alcohol, toluene, bromoalkane, and sodium hydroxide is 0.1-0.13 mol: 220-230 mL: 0.1 mol: 0.1-0.2 g;

[0017] During the reaction of step A2, diethylphosphite chloride reacts with the alcoholic hydroxyl group of the hydroxyl product to generate a bromoalkane containing phosphite; the hydroxyl group of p-nitrobenzyl alcohol and the bromoalkane are dehydrobrominated to generate an etherified product containing a nitro group;

[0018] Step A3: Add the etherification product and ethyl acetate into a three-necked flask, heat to 45-55°C, start reflux stirring, then add sodium dithionite, and reflux stirring for 1-1.5h to obtain an amino product; add the amino product and glycidyl acrylate into a round-bottom flask, add dimethyl sulfoxide, stir and react at 50°C for 24h, filter, and dry to obtain a functional monomer;

[0019] Further, the usage ratio of the etherification product, ethyl acetate, and sodium dithionite is 0.1 mol: 240-250 mL: 0.1-0.15 mol; the usage ratio of the amino product, glycidyl acrylate, and dimethyl sulfoxide is 0.1 mol: 0.2 mol: 270-280 mL;

[0020] During the reaction of step A3, the nitro group of the etherification product is reduced to an amino group to obtain an amino product; the amino group of the amino product reacts with the epoxy group of glycidyl acrylate to generate a functional monomer containing an alcoholic hydroxyl group;

[0021] Step A4: In a nitrogen atmosphere, toluene, functional monomers and crosslinking agents were added to the reaction bottle, and after stirring for 10-15 minutes, polypropylene was added and stirred for another 10-15 minutes. The reaction bottle was sealed and then 60 After irradiation with Coγ rays for 8-10 hours, the mixture is taken out and then washed with anhydrous ethanol, extracted with acetone and dried to obtain modified polypropylene; the asphalt is heated to 180-190°C, and then the modified polypropylene is added and stirred continuously for 1.5-2 hours to obtain modified asphalt;

[0022] Further, the dosage ratio of toluene, functional monomer, crosslinking agent, and polypropylene is 400-450 mL: 10-15 g: 7-9 g: 100-110 g, and the crosslinking agent is divinylbenzene; the dosage ratio of asphalt and modified polypropylene is 10 g: 0.2-0.3 g;

[0023] During the reaction of step A4, 60Under the irradiation of Coγ rays and with the assistance of a cross-linking agent, the functional monomer is grafted onto polypropylene to obtain modified polypropylene; the modified polypropylene is then melt-blended with asphalt to obtain modified asphalt.

[0024] The modified microcapsules are prepared by the following steps:

[0025] Step B1: add p-nitrocinnamic acid and DOPO to a flask, start stirring, heat to 125-135°C, and stir at constant temperature for 3-4 hours to obtain a nitro product; in a nitrogen atmosphere, add the nitro product and toluene to a flask, heat to 45°C, add pyridine, start stirring, add γ-glycidyl ether silyl propyl sesquioxane to the flask, stir and react for 8-10 hours, then heat to 110-120°C, reflux and stir for 1-2 hours to obtain a hydroxyl product 1;

[0026] Further, the dosage ratio of p-nitrocinnamic acid and DOPO is 0.1 mol: 0.1 mol; the dosage ratio of nitro product, toluene, pyridine and γ-glycidyl ether silyl propyl sesquioxane is 0.1 mol: 180-190 mL: 0.010-0.015 mol: 50-52 g;

[0027] During the reaction of step B1, DOPO reacts with the carbon-carbon double bond of p-nitrocinnamic acid to obtain a nitro product containing a carboxyl group; the carboxyl group of the nitro product reacts with the epoxy group of γ-glycidyloxysilylpropylsesquioxane to obtain a hydroxyl product 1;

[0028] Step B2: Add the hydroxyl product 1 and ethyl acetate into a three-necked flask, heat to 45-55°C, start reflux stirring, then add sodium dithionite, and reflux stirring to react for 1-1.5h to obtain a modified curing agent;

[0029] Further, the usage ratio of the hydroxyl product 1, ethyl acetate, and sodium dithionite is 120-125 g: 250-260 mL: 0.1-0.15 mol;

[0030] During the reaction of step B2, the nitro group of the hydroxyl product 1 is reduced to an amino group to obtain a modified curing agent;

[0031] Step B3: Add epoxy resin, modified curing agent, diluent and dispersant to a reaction bottle and stir for 20-30 minutes to obtain a coating material; then immerse the porous zeolite in the regeneration agent, stir for 5-10 minutes, let stand for 30 minutes, then add the coating material, stir for 15 minutes, and obtain a modified microcapsule;

[0032] Furthermore, the usage ratio of epoxy resin, modified curing agent, diluent and dispersant is 45g:35g:25g:1g; the usage ratio of porous zeolite, regeneration agent and packaging material is 7.8g:6.5g:15g; the epoxy resin is bisphenol A type epoxy resin, the diluent is neopentyl glycol glycidyl ether, the dispersant is sodium succinate, and the regeneration agent is sunflower oil;

[0033] During the reaction of step B3, the regeneration agent is used as the capsule core and the porous zeolite is used as the capsule wall. The capsule core is adsorbed and stored in the capsule wall. The periphery of the capsule wall is wrapped with a wrapping material prepared by epoxy resin and modified curing agent to form a modified microcapsule.

[0034] Beneficial effects of the invention: The invention discloses a high-strength wear-resistant asphalt concrete, which is prepared from raw materials such as modified asphalt, crushed stone, natural sand, mineral powder, steel slag powder and modified microcapsules. The steel slag powder has the advantages of high strength, rough surface, wear resistance and firm combination with asphalt, and meets the use requirements of high-strength wear-resistant asphalt concrete.

[0035] The synthesized modified asphalt is obtained by melt-blending modified polypropylene obtained by grafting functional monomers with polypropylene with asphalt, and the functional monomers introduce hindered phenol structure, phosphite structure and alcohol hydroxyl group into polypropylene; the hindered phenol structure generates hydroperoxide in the oxidative degradation reaction of polymer and asphalt, so that the oxidative degradation reaction is terminated, and the phosphite can reduce and decompose the hydroperoxide, and the hindered phenol structure and the phosphite structure produce rapid intramolecular synergistic effect, which prevents the oxidation reaction of polymer and asphalt from continuing and improves the aging resistance of the modified asphalt; the alcohol hydroxyl group and the hydroxyl group in bisphenol A epoxy resin produce hydrogen bond cross-linking, so that the compatibility of the modified asphalt and the modified microcapsule is increased, which is beneficial to the uniform dispersion of the modified asphalt and the modified microcapsule in the asphalt concrete system, and is more beneficial to the improvement of the strength of the asphalt concrete by the modified polypropylene; the use of modified asphalt can improve the aging resistance and compressive strength of the asphalt concrete.

[0036] The modified microcapsules synthesized, whose wrapping material is prepared from raw materials such as epoxy resin and modified curing agent, introduce DOPO and POSS structures into the wrapping material through the modified curing agent; when the matrix burns, the DOPO structure causes the polymer surface to dehydrate and degrade to form a carbon layer, and the phosphorus-containing derivatives produced at the same time cover the polymer surface, isolating the transfer of combustible gas and heat, and playing a physical shielding and flame retardant role in the condensed phase; POSS is a core-shell structure containing organic-inorganic hybrids, and its internal inorganic framework is a hexahedral cage structure composed of Si-O-Si or Si-O bonds, which has extremely high structural stability and thermodynamic stability; when the asphalt road formed by asphalt concrete When the internal surface is damaged to form cracks and the cracks extend to the surface of the microcapsule, the microcapsule wall is ruptured by the stress at the crack tip, and the wrapped regeneration agent, i.e., sunflower oil, flows out under the action of capillary action and diffuses into the asphalt around the crack. Due to the low viscosity of sunflower oil, the aged asphalt around the crack is softened, thereby reducing the viscosity of the asphalt, accelerating the self-healing speed of the crack, and achieving the effect of sealing the crack; therefore, the flame retardancy and high temperature resistance of the modified microcapsule are improved, and it has good compatibility with modified asphalt, and can better play the role of improving the self-healing ability of asphalt concrete materials; therefore, the use of modified microcapsules can make asphalt concrete have good flame retardancy, high temperature resistance and self-healing ability. DETAILED DESCRIPTION

[0037] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] Example 1

[0039] A modified asphalt, the preparation of which comprises the following steps:

[0040] Step A1: Add undecene bromide to dichloromethane, start stirring, then add 3-chloroperbenzoic acid, stir and react at room temperature for 4 hours to obtain an epoxy product; in a nitrogen atmosphere, add 3,5-di-tert-butyl-4-hydroxyphenylacetic acid and toluene to a flask, heat to 45°C, add pyridine, start stirring, add the epoxy product to the flask, stir and react for 8 hours, then heat to 110°C, stir for 1 hour to obtain a hydroxyl product; the amount ratio of undecene bromide, dichloromethane and 3-chloroperbenzoic acid is 0.1 mol: 120 mL: 0.1 mol; the amount ratio of 3,5-di-tert-butyl-4-hydroxyphenylacetic acid, toluene, pyridine and epoxy product is 0.1 mol: 180 mL: 0.010 mol: 0.1 mol;

[0041] Step A2: Add the hydroxyl product to toluene, stir for 5 minutes to obtain a toluene solution of the hydroxyl product, add diethylphosphite chloride and triethylamine to a flask, slowly drop the toluene solution of the hydroxyl product into the flask at 40°C, stir at constant temperature for 1 hour, heat to 60°C, stir at constant temperature for 5 hours, filter, and distill under reduced pressure to obtain bromoalkane; add p-nitrobenzyl alcohol to toluene, add bromoalkane and sodium hydroxide under stirring, and react at 40°C for 4 hours to obtain an etherification product; the dosage ratio of the hydroxyl product to toluene is 0.1 mol: 185 mL; the dosage ratio of diethylphosphite chloride, triethylamine, and toluene solution of the hydroxyl product is 16.5 g: 20 mL: 195 mL; the dosage ratio of p-nitrobenzyl alcohol, toluene, bromoalkane, and sodium hydroxide is 0.1 mol: 220 mL: 0.1 mol: 0.1 g;

[0042] Step A3: Add the etherification product and ethyl acetate into a three-necked flask, heat to 45°C, start reflux stirring, then add sodium dithionite, and reflux stirring for 1 hour to obtain an amino product; add the amino product and glycidyl acrylate into a round-bottom flask, add dimethyl sulfoxide, stir and react at 50°C for 24 hours, filter, and dry to obtain a functional monomer; the amount ratio of the etherification product, ethyl acetate, and sodium dithionite is 0.1 mol: 240 mL: 0.1 mol; the amount ratio of the amino product, glycidyl acrylate, and dimethyl sulfoxide is 0.1 mol: 0.2 mol: 270 mL;

[0043] Step A4: In a nitrogen atmosphere, toluene, functional monomers and crosslinking agents were added to the reaction bottle, and after stirring for 10 min, polypropylene was added and stirred for another 10 min. The reaction bottle was sealed and then 60 After 8 hours of Coγ-ray irradiation, the mixture was taken out and then rinsed with anhydrous ethanol, extracted with acetone and dried to obtain modified polypropylene; the asphalt was heated to 180°C, and then the modified polypropylene was added and stirred continuously for 1.5 hours to obtain the modified asphalt; the dosage ratio of toluene, functional monomer, cross-linking agent and polypropylene was 400mL:10g:7g:100g, and the cross-linking agent was divinylbenzene; the dosage ratio of asphalt and modified polypropylene was 10g:0.2g.

[0044] Example 2

[0045] A modified asphalt, the preparation of which comprises the following steps:

[0046] Step A1: Add undecene bromide to dichloromethane, start stirring, then add 3-chloroperbenzoic acid, stir and react at room temperature for 4.5 hours to obtain an epoxy product; in a nitrogen atmosphere, add 3,5-di-tert-butyl-4-hydroxyphenylacetic acid and toluene to a flask, heat to 45°C, add pyridine, start stirring, add the epoxy product to the flask, stir and react for 9 hours, then heat to 115°C, stir for 1.5 hours to obtain a hydroxyl product; the amount ratio of undecene bromide, dichloromethane and 3-chloroperbenzoic acid is 0.1 mol: 125 mL: 0.1 mol; the amount ratio of 3,5-di-tert-butyl-4-hydroxyphenylacetic acid, toluene, pyridine and epoxy product is 0.1 mol: 185 mL: 0.013 mol: 0.1 mol;

[0047] Step A2: Add the hydroxyl product to toluene, stir for 8 minutes to obtain a toluene solution of the hydroxyl product, add diethylphosphite chloride and triethylamine to a flask, slowly drop the toluene solution of the hydroxyl product into the flask at 40°C, stir at constant temperature for 1 hour, raise the temperature to 60°C, stir at constant temperature for 5.5 hours, filter, and distill under reduced pressure to obtain bromoalkane; add p-nitrobenzyl alcohol to toluene, add bromoalkane and sodium hydroxide under stirring, and react at 40°C with stirring for 4.5 hours to obtain an etherification product; the dosage ratio of the hydroxyl product to toluene is 0.1 mol: 190 mL; the dosage ratio of diethylphosphite chloride, triethylamine, and toluene solution of the hydroxyl product is 17.0 g: 23 mL: 200 mL; the dosage ratio of p-nitrobenzyl alcohol, toluene, bromoalkane, and sodium hydroxide is 0.12 mol: 225 mL: 0.1 mol: 0.15 g;

[0048] Step A3: Add the etherification product and ethyl acetate into a three-necked flask, heat to 50°C, start reflux stirring, then add sodium dithionite, and reflux stirring for 1.3 hours to obtain an amino product; add the amino product and glycidyl acrylate into a round-bottom flask, add dimethyl sulfoxide, stir and react at 50°C for 24 hours, filter, and dry to obtain a functional monomer; the amount ratio of the etherification product, ethyl acetate, and sodium dithionite is 0.1 mol: 245 mL: 0.3 mol; the amount ratio of the amino product, glycidyl acrylate, and dimethyl sulfoxide is 0.1 mol: 0.2 mol: 275 mL;

[0049] Step A4: In a nitrogen atmosphere, toluene, functional monomers and crosslinking agents were added to the reaction bottle, and after stirring for 13 minutes, polypropylene was added and stirred for another 13 minutes. The reaction bottle was sealed and then 60After irradiation with Coγ rays for 9 hours, the mixture was taken out and then rinsed with anhydrous ethanol, extracted with acetone and dried to obtain modified polypropylene. The asphalt was heated to 185°C, and then the modified polypropylene was added and stirred continuously for 1.7 hours to obtain the modified asphalt. The dosage ratio of toluene, functional monomer, cross-linking agent and polypropylene was 430mL:13g:8g:105g, and the cross-linking agent was divinylbenzene. The dosage ratio of asphalt and modified polypropylene was 10g:0.25g.

[0050] Example 3

[0051] A modified asphalt, the preparation of which comprises the following steps:

[0052] Step A1: Add undecene bromide to dichloromethane, start stirring, then add 3-chloroperbenzoic acid, stir and react at room temperature for 5 hours to obtain an epoxy product; in a nitrogen atmosphere, add 3,5-di-tert-butyl-4-hydroxyphenylacetic acid and toluene to a flask, heat to 45°C, add pyridine, start stirring, add the epoxy product to the flask, stir and react for 10 hours, then heat to 120°C, stir for 2 hours to obtain a hydroxyl product; the amount ratio of undecene bromide, dichloromethane and 3-chloroperbenzoic acid is 0.1 mol: 130 mL: 0.1 mol; the amount ratio of 3,5-di-tert-butyl-4-hydroxyphenylacetic acid, toluene, pyridine and epoxy product is 0.1 mol: 190 mL: 0.015 mol: 0.1 mol;

[0053] Step A2: Add the hydroxyl product to toluene, stir for 10 minutes to obtain a toluene solution of the hydroxyl product, add diethylphosphite chloride and triethylamine to a flask, slowly drop the toluene solution of the hydroxyl product into the flask at 40°C, stir at constant temperature for 1 hour, heat to 60°C, stir at constant temperature for 6 hours, filter, and distill under reduced pressure to obtain bromoalkane; add p-nitrobenzyl alcohol to toluene, add bromoalkane and sodium hydroxide under stirring, and react at 40°C for 5 hours to obtain an etherification product; the dosage ratio of the hydroxyl product to toluene is 0.1 mol: 195 mL; the dosage ratio of diethylphosphite chloride, triethylamine, and toluene solution of the hydroxyl product is 17.5 g: 25 mL: 205 mL; the dosage ratio of p-nitrobenzyl alcohol, toluene, bromoalkane, and sodium hydroxide is 0.13 mol: 230 mL: 0.1 mol: 0.2 g;

[0054] Step A3: Add the etherification product and ethyl acetate into a three-necked flask, heat to 55°C, start reflux stirring, then add sodium dithionite, and reflux stirring for 1.5 hours to obtain an amino product; add the amino product and glycidyl acrylate into a round-bottom flask, add dimethyl sulfoxide, stir and react at 50°C for 24 hours, filter, and dry to obtain a functional monomer; the amount ratio of the etherification product, ethyl acetate, and sodium dithionite is 0.1 mol: 250 mL: 0.15 mol; the amount ratio of the amino product, glycidyl acrylate, and dimethyl sulfoxide is 0.1 mol: 0.2 mol: 280 mL;

[0055] Step A4: In a nitrogen atmosphere, toluene, functional monomers and crosslinking agents were added to the reaction bottle, and after stirring for 15 min, polypropylene was added and stirred for another 15 min. The reaction bottle was sealed and then 60 After 10 hours of Coγ-ray irradiation, the mixture was taken out and then rinsed with anhydrous ethanol, extracted with acetone and dried to obtain modified polypropylene; the asphalt was heated to 190°C, and then the modified polypropylene was added and stirred continuously for 2 hours to obtain the modified asphalt; the dosage ratio of toluene, functional monomer, cross-linking agent and polypropylene was 450mL:15g:9g:110g, and the cross-linking agent was divinylbenzene; the dosage ratio of asphalt and modified polypropylene was 10g:0.3g.

[0056] Example 4

[0057] A modified microcapsule, the preparation of which comprises the following steps:

[0058] Step B1: add p-nitrocinnamic acid and DOPO to a flask, start stirring, heat to 125°C, and react at constant temperature and stirring for 3 hours to obtain a nitro product; in a nitrogen atmosphere, add the nitro product and toluene to a flask, heat to 45°C, add pyridine, start stirring, add γ-glycidyloxysilylpropylsesquioxane to the flask, stir and react for 8 hours, then heat to 110°C, reflux and stir for 1 hour to obtain a hydroxyl product 1; the dosage ratio of p-nitrocinnamic acid and DOPO is 0.1 mol:0.1 mol; the dosage ratio of nitro product, toluene, pyridine and γ-glycidyloxysilylpropylsesquioxane is 0.1 mol:180 mL:0.010 mol:50 g;

[0059] Step B2: Add the hydroxyl product 1 and ethyl acetate into a three-necked flask, heat to 45°C, start reflux stirring, then add sodium dithionite, and reflux stirring for 1 hour to obtain a modified curing agent; the dosage ratio of the hydroxyl product 1, ethyl acetate, and sodium dithionite is 120g:250mL:0.1mol;

[0060] Step B3: adding epoxy resin, modified curing agent, diluent and dispersant to a reaction bottle and stirring for 20 minutes to obtain a wrapping material; then immersing the porous zeolite in the regeneration agent, stirring for 5 minutes and then standing for 30 minutes, then adding the wrapping material and stirring for 15 minutes to obtain a modified microcapsule; the amount ratio of epoxy resin, modified curing agent, diluent and dispersant is 45g:35g:25g:1g; the amount ratio of porous zeolite, regeneration agent and wrapping material is 7.8g:6.5g:15g; the epoxy resin is bisphenol A epoxy resin, the diluent is neopentyl glycol glycidyl ether, the dispersant is sodium succinate, and the regeneration agent is sunflower oil.

[0061] Example 5

[0062] A modified microcapsule, the preparation of which comprises the following steps:

[0063] Step B1: add p-nitrocinnamic acid and DOPO to a flask, start stirring, heat to 130°C, and react at constant temperature and stirring for 3.5 hours to obtain a nitro product; in a nitrogen atmosphere, add the nitro product and toluene to a flask, heat to 45°C, add pyridine, start stirring, add γ-glycidyloxysilylpropylsesquioxane to the flask, stir and react for 9 hours, then heat to 115°C, reflux and stir for 1.5 hours to obtain a hydroxyl product 1; the amount ratio of p-nitrocinnamic acid and DOPO is 0.1 mol:0.1 mol; the amount ratio of nitro product, toluene, pyridine and γ-glycidyloxysilylpropylsesquioxane is 0.1 mol:185 mL:0.013 mol:51 g;

[0064] Step B2: Add the hydroxyl product 1 and ethyl acetate into a three-necked flask, heat to 50°C, start reflux stirring, then add sodium dithionite, and reflux stirring to react for 1.3 hours to obtain a modified curing agent; the dosage ratio of the hydroxyl product 1, ethyl acetate, and sodium dithionite is 123g:255mL:0.13mol;

[0065] Step B3: adding epoxy resin, modified curing agent, diluent and dispersant to a reaction bottle and stirring for 25 minutes to obtain a wrapping material; then immersing the porous zeolite in the regeneration agent, stirring for 7 minutes and then standing for 30 minutes, then adding the wrapping material and stirring for 15 minutes to obtain a modified microcapsule; the amount ratio of epoxy resin, modified curing agent, diluent and dispersant is 45g:35g:25g:1g; the amount ratio of porous zeolite, regeneration agent and wrapping material is 7.8g:6.5g:15g; the epoxy resin is bisphenol A epoxy resin, the diluent is neopentyl glycol glycidyl ether, the dispersant is sodium succinate, and the regeneration agent is sunflower oil.

[0066] Example 6

[0067] A modified microcapsule, the preparation of which comprises the following steps:

[0068] Step B1: add p-nitrocinnamic acid and DOPO to a flask, start stirring, heat to 135°C, and stir at constant temperature for 4 hours to obtain a nitro product; in a nitrogen atmosphere, add the nitro product and toluene to a flask, heat to 45°C, add pyridine, start stirring, add γ-glycidyloxysilylpropylsesquioxane to the flask, stir and react for 10 hours, then heat to 120°C, reflux and stir for 2 hours to obtain a hydroxyl product 1; the dosage ratio of p-nitrocinnamic acid and DOPO is 0.1 mol:0.1 mol; the dosage ratio of nitro product, toluene, pyridine and γ-glycidyloxysilylpropylsesquioxane is 0.1 mol:190 mL:0.015 mol:52 g;

[0069] Step B2: Add the hydroxyl product 1 and ethyl acetate into a three-necked flask, heat to 55°C, start reflux stirring, then add sodium dithionite, and reflux stirring to react for 1.5 hours to obtain a modified curing agent; the dosage ratio of the hydroxyl product 1, ethyl acetate, and sodium dithionite is 125g:260mL:0.15mol;

[0070] Step B3: adding epoxy resin, modified curing agent, diluent and dispersant to a reaction bottle and stirring for 30 minutes to obtain a wrapping material; then immersing the porous zeolite in the regeneration agent, stirring for 10 minutes and then standing for 30 minutes, then adding the wrapping material and stirring for 15 minutes to obtain a modified microcapsule; the amount ratio of epoxy resin, modified curing agent, diluent and dispersant is 45g:35g:25g:1g; the amount ratio of porous zeolite, regeneration agent and wrapping material is 7.8g:6.5g:15g; the epoxy resin is bisphenol A epoxy resin, the diluent is neopentyl glycol glycidyl ether, the dispersant is sodium succinate, and the regeneration agent is sunflower oil.

[0071] Example 7

[0072] A high-strength wear-resistant asphalt concrete comprises the following raw materials in parts by weight: 6 parts of modified asphalt, 45 parts of crushed stone, 25 parts of natural sand, 7 parts of mineral powder, 5 parts of steel slag powder and 0.4 parts of modified microcapsules;

[0073] The production process of the high-strength wear-resistant asphalt concrete comprises the following steps:

[0074] Crushed stone, natural sand and steel slag powder were stirred and heated at 160°C for 30 minutes to obtain a preheated mixture, and the modified asphalt obtained in Example 1 was heated to 150°C and added to the mixture, and then the modified microcapsules obtained in Example 4 were added and stirred for 2 minutes, and then mineral powder was added and stirred for another 2 minutes to obtain high-strength wear-resistant asphalt concrete.

[0075] Example 8

[0076] A high-strength wear-resistant asphalt concrete comprises the following raw materials in parts by weight: 7 parts of modified asphalt, 50 parts of crushed stone, 28 parts of natural sand, 8 parts of mineral powder, 6 parts of steel slag powder and 0.6 parts of modified microcapsules;

[0077] The production process of the high-strength wear-resistant asphalt concrete comprises the following steps:

[0078] Crushed stone, natural sand and steel slag powder were stirred and heated at 165°C for 30 minutes to obtain a preheated mixture, and the modified asphalt obtained in Example 2 was heated to 155°C and added to the mixture, and then the modified microcapsules obtained in Example 5 were added and stirred for 2 minutes, and then mineral powder was added and stirred for another 2 minutes to obtain high-strength wear-resistant asphalt concrete.

[0079] Example 9

[0080] A high-strength wear-resistant asphalt concrete comprises the following raw materials in parts by weight: 8 parts of modified asphalt, 55 parts of crushed stone, 30 parts of natural sand, 9 parts of mineral powder, 7 parts of steel slag powder and 0.8 parts of modified microcapsules;

[0081] The production process of the high-strength wear-resistant asphalt concrete comprises the following steps:

[0082] Crushed stone, natural sand and steel slag powder were stirred and heated at 170°C for 30 minutes to obtain a preheated mixture, and the modified asphalt obtained in Example 3 was heated to 160°C and added to the mixture, and then the modified microcapsules obtained in Example 6 were added and stirred for 3 minutes, and then mineral powder was added and stirred for another 3 minutes to obtain high-strength wear-resistant asphalt concrete.

[0083] Comparative Example 1

[0084] This comparative example is commercially available asphalt concrete.

[0085] Comparative Example 2

[0086] Compared with Example 9, the functional monomer used in Example 3 is replaced with hydroxyethyl acrylate, and the rest is exactly the same as Example 9, that is, hindered phenol and phosphite structure are not introduced, and high-strength wear-resistant asphalt concrete is obtained.

[0087] Comparative Example 3

[0088] Compared with Example 9, the functional monomer used in Example 3 is replaced with methyl acrylate, and the rest is exactly the same as Example 9, that is, no alcohol hydroxyl group, hindered phenol and phosphite structure are introduced, and high-strength wear-resistant asphalt concrete is obtained.

[0089] Comparative Example 4

[0090] Compared with Example 9, the γ-glycidyl ether silyl propyl sesquioxane used in Example 6 was replaced with acrylic acid glycidyl ether, and the rest was exactly the same as Example 9, that is, the POSS structure was not introduced, and high-strength wear-resistant asphalt concrete was obtained.

[0091] The high-strength wear-resistant asphalt concrete prepared by the present invention is further tested for its effects, and the test results are as follows.

[0092] For the asphalt concrete of Examples 7-9 and Comparative Examples 1-3, the test specimens were prepared by the compaction method in T0702-2011 of the asphalt mixture test specimen preparation method of JTJE20-2011 "Test Procedure for Asphalt and Asphalt Mixtures in Highway Engineering"; the test specimens were cut into 70mm*70mm*10mm concrete blocks and placed in a cone calorimeter to test the ignition time. The thermal radiation intensity during the test was 50kW / m 2 ; A fracture strength recovery test was conducted on a 70mm*70mm*10mm concrete block to determine the crack healing rate; the compressive strength was determined according to ASTM D1074-2017 Standard Test Method for Compressive Strength of Asphalt Mixtures; the PAV aging temperature test was conducted on the specimens to determine the high temperature resistance of asphalt concrete; the specimens were placed in an air oven at 150°C for 7 days, and the compressive strength retention rate after aging was determined with reference to JTJE20-2011, and the results are recorded in Table 1;

[0093] The fracture strength recovery test method is as follows: the specimen is placed in a constant temperature test box at -10°C for 4 hours, and then a three-point bending test is performed on the specimen to obtain the initial crack width L0; the broken specimen is heated until the surface temperature reaches 120°C, and after 120 seconds, the heating is stopped, and the specimen is placed at room temperature to cool; the specimen is placed in a constant temperature test box at -10°C for 4 hours, and then a three-point bending test is performed on the specimen to obtain the crack width L1 after induction heating healing. The crack width ratio of the specimen before and after the two bending tests is calculated to obtain the crack healing rate of the specimen, and the results are recorded in Table 1.

[0094] Table 1:

[0095]

[0096] According to the data in Table 1, it is known that asphalt concrete prepared by the present invention has good flame retardant properties, self-healing properties, compressive strength, high temperature resistance and aging resistance as compared with Comparative Example 1. As compared with Comparative Example 2, Example 9 uses modified asphalt, introduces hindered phenol and phosphite structure, and is more conducive to the improvement of polymer and asphalt aging resistance, thereby improving the aging resistance of asphalt concrete. As compared with Comparative Example 3, Example 9 uses modified asphalt, introduces alcoholic hydroxyl, hindered phenol and phosphite structure, and alcoholic hydroxyl makes the compatibility of modified asphalt and modified microcapsule better, which is more conducive to the improvement of modified asphalt to the compressive strength and aging resistance of asphalt concrete, and also helps the improvement of flame retardant, self-healing and high temperature resistance of modified microcapsule to asphalt concrete. As compared with Comparative Example 4, Example 9 uses modified microcapsule, introduces POSS structure, which is more conducive to the improvement of high temperature resistance of modified microcapsule, and can effectively improve the high temperature resistance of asphalt concrete.

[0097] The above contents are merely examples and explanations of the concept of the present invention. The technicians in this technical field may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the concept of the invention or exceed the scope defined by the claims, they should all fall within the protection scope of the present invention.

Claims

1. A high-strength wear-resistant asphalt concrete, characterized in that: The raw materials include the following parts by weight: 6-8 parts of modified asphalt, 45-55 parts of crushed stone, 25-30 parts of natural sand, 7-9 parts of mineral powder, 5-7 parts of steel slag powder and 0.4-0.8 parts of modified microcapsules; The modified asphalt is prepared by the following steps: Step A1: Add undecene bromide to dichloromethane, start stirring, then add 3-chloroperoxybenzoic acid, stir and react at room temperature for 4-5 hours to obtain an epoxy product; in a nitrogen atmosphere, add 3,5-di-tert-butyl-4-hydroxyphenylacetic acid and toluene to a flask, heat to 45°C, add pyridine, start stirring, add the epoxy product to the flask, stir and react for 8-10 hours, then heat to 110-120°C, stir for 1-2 hours to obtain a hydroxyl product; Step A2: adding the hydroxyl product to toluene, stirring for 5-10 minutes to obtain a toluene solution of the hydroxyl product, adding diethylphosphite chloride and triethylamine to a flask, slowly dropping the toluene solution of the hydroxyl product into the flask at 40°C, stirring at a constant temperature for 1 hour, raising the temperature to 60°C, stirring at a constant temperature for 5-6 hours, filtering, and distilling under reduced pressure to obtain a bromoalkane; adding p-nitrobenzyl alcohol to toluene, adding the bromoalkane and sodium hydroxide under stirring, and reacting at 40°C with stirring for 4-5 hours to obtain an etherification product; Step A3: Add the etherification product and ethyl acetate into a three-necked flask, heat to 45-55°C, start reflux stirring, then add sodium dithionite, and reflux stirring for 1-1.5h to obtain an amino product; add the amino product and glycidyl acrylate into a round-bottom flask, add dimethyl sulfoxide, stir and react at 50°C for 24h, filter, and dry to obtain a functional monomer; Step A4: In a nitrogen atmosphere, toluene, functional monomers and crosslinking agents were added to the reaction bottle, and after stirring for 10-15 minutes, polypropylene was added and stirred for another 10-15 minutes. The reaction bottle was sealed and then 60 After irradiation with Coγ rays for 8-10 hours, the mixture is taken out and then rinsed with anhydrous ethanol, extracted with acetone and dried to obtain modified polypropylene. The asphalt is heated to 180-190°C, and then the modified polypropylene is added and stirred continuously for 1.5-2 hours to obtain the modified asphalt.

2. The high-strength wear-resistant asphalt concrete according to claim 1, characterized in that: In step A1, the ratio of undecene bromide, dichloromethane and 3-chloroperbenzoic acid is 0.1 mol: 120-130 mL: 0.1 mol; the ratio of 3,5-di-tert-butyl-4-hydroxyphenylacetic acid, toluene, pyridine and epoxidation product is 0.1 mol: 180-190 mL: 0.010-0.015 mol: 0.1 mol.

3. The high-strength wear-resistant asphalt concrete according to claim 1, characterized in that: In step A2, the usage ratio of the hydroxyl product and toluene is 0.1 mol: 185-195 mL; the usage ratio of diethylphosphite chloride, triethylamine and toluene solution of the hydroxyl product is 16.5-17.5 g: 20-25 mL: 195-205 mL; the usage ratio of p-nitrobenzyl alcohol, toluene, bromoalkane and sodium hydroxide is 0.1-0.13 mol: 220-230 mL: 0.1 mol: 0.1-0.2 g.

4. The high-strength wear-resistant asphalt concrete according to claim 1, characterized in that: In step A3, the usage ratio of the etherification product, ethyl acetate and sodium dithionite is 0.1 mol: 240-250 mL: 0.1-0.15 mol; the usage ratio of the amino product, glycidyl acrylate and dimethyl sulfoxide is 0.1 mol: 0.2 mol: 270-280 mL.

5. The high-strength wear-resistant asphalt concrete according to claim 1, characterized in that: In step A4, the usage ratio of toluene, functional monomer, cross-linking agent and polypropylene is 400-450 mL: 10-15 g: 7-9 g: 100-110 g, and the cross-linking agent is divinylbenzene; the usage ratio of asphalt and modified polypropylene is 10 g: 0.2-0.3 g.

6. The high-strength wear-resistant asphalt concrete according to claim 1, characterized in that: The modified microcapsules are prepared by the following steps: Step B1: add p-nitrocinnamic acid and DOPO to a flask, start stirring, heat to 125-135°C, and stir at constant temperature for 3-4 hours to obtain a nitro product; in a nitrogen atmosphere, add the nitro product and toluene to a flask, heat to 45°C, add pyridine, start stirring, add γ-glycidyloxysilylpropylsesquioxane to the flask, stir and react for 8-10 hours, then heat to 110-120°C, reflux and stir for 1-2 hours to obtain a hydroxyl product 1; Step B2: Add the hydroxyl product 1 and ethyl acetate into a three-necked flask, heat to 45-55°C, start reflux stirring, then add sodium dithionite, and reflux stirring to react for 1-1.5h to obtain a modified curing agent; Step B3: Add epoxy resin, modified curing agent, diluent and dispersant to a reaction bottle and stir for 20-30 minutes to obtain a coating material; then immerse the porous zeolite in the regeneration agent, stir for 5-10 minutes and let stand for 30 minutes, then add the coating material and stir for 15 minutes to obtain modified microcapsules.

7. The high-strength wear-resistant asphalt concrete according to claim 6, characterized in that: In step B1, the ratio of p-nitrocinnamic acid to DOPO is 0.1 mol:0.1 mol; the ratio of nitro product, toluene, pyridine and γ-glycidyloxysilylpropylsesquioxane is 0.1 mol:180-190 mL:0.010-0.015 mol:50-52 g.

8. The high-strength wear-resistant asphalt concrete according to claim 6, characterized in that: In step B2, the usage ratio of the hydroxyl product 1, ethyl acetate and sodium dithionite is 120-125 g: 250-260 mL: 0.1-0.15 mol.

9. The high-strength wear-resistant asphalt concrete according to claim 6, characterized in that: In step B3, the usage ratio of epoxy resin, modified curing agent, diluent and dispersant is 45g:35g:25g:1g; the usage ratio of porous zeolite, regeneration agent and packaging material is 7.8g:6.5g:15g; the epoxy resin is bisphenol A type epoxy resin, the diluent is neopentyl glycol glycidyl ether, the dispersant is sodium succinate, and the regeneration agent is sunflower oil.

10. The production process of high-strength wear-resistant asphalt concrete according to claim 1, characterized in that: The steps include: Crushed stone, natural sand and steel slag powder are stirred and heated at 160-170°C for 30 minutes to obtain a preheated mixture, and then the modified asphalt is heated to 150-160°C and added to the mixture, and then the modified microcapsules are added and stirred for 2-3 minutes, and then the mineral powder is added and stirred for another 2-3 minutes to obtain high-strength wear-resistant asphalt concrete.

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