A modified asphalt mortar for road repair and its preparation method

Abstract

The present invention discloses a modified asphalt mortar for road repair and its preparation method, which relates to the field of asphalt mortar. When preparing the modified asphalt mortar for road repair in the present invention, 4-acryloxy-2-hydroxybenzophenone is reacted with octaaminopropylcage polyhedral oligomeric silsesquioxane to obtain modified cage polyhedral oligomeric silsesquioxane; quartz sand is successively reacted with 3-aminopropyltrimethoxysilane and maleic anhydride to obtain modified quartz sand; glycidyl methacrylate, N,N-dimethylallylamine, and 2-allylfuran are polymerized and then reacted with N-(trifluoromethylthio)phthalimide to obtain modified epoxy polymer; the asphalt is heated and mixed with the modified epoxy polymer, modified quartz sand, and modified cage polyhedral oligomeric silsesquioxane to obtain the modified asphalt mortar for road repair. The modified asphalt mortar for road repair prepared by the present invention has the abilities of waterproofing, self-healing, high temperature resistance, and anti-aging.

Description

Technical Field

[0001] The present invention relates to the field of asphalt mortar, and specifically to a modified asphalt mortar for road repair and a preparation method thereof. Background Art

[0002] As the main paving form of highways in China, asphalt pavements have the advantages of high flatness, seamless joints, low noise, low dust generation, short construction period, simple maintenance, etc. compared with cement concrete pavements, and are widely used.

[0003] With the increase in traffic volume and service time, asphalt pavements are prone to diseases such as looseness, cracks, settlement, and potholes. If not repaired in time, when a car passes by, it is easy to cause bumps, and under the action of rainwater and vehicle loads, it will further expand and even penetrate into the base layer, affecting the durability and service life of the asphalt pavement and threatening driving safety. Therefore, this application introduces a modified asphalt mortar with self-healing ability. Summary of the Invention

[0004] The purpose of the present invention is to provide a modified asphalt mortar for road repair and a preparation method thereof to solve the problems existing in the prior art.

[0005] A modified asphalt mortar for road repair, wherein the modified asphalt mortar for road repair is prepared by heating asphalt and mixing it with a modified epoxy polymer, modified quartz sand, and modified cage-like polyhedral oligomeric silsesquioxane;

[0006] The modified epoxy polymer is prepared by polymerizing glycidyl methacrylate, N,N-dimethylallylamine, and 2-allylfuran and then reacting with N-(trifluoromethylthio)phthalimide;

[0007] The modified quartz sand is prepared by reacting quartz sand with 3-aminopropyltrimethoxysilane and maleic anhydride in sequence;

[0008] The modified cage-like polyhedral oligomeric silsesquioxane is prepared by reacting 4-allyloxy-2-hydroxybenzophenone with octaaminopropyl cage-like polyhedral oligomeric silsesquioxane.

[0009] A preparation method of a modified asphalt mortar for road repair, wherein the preparation method of the modified asphalt mortar for road repair mainly includes the following preparation steps:

[0010] (1) Mix 4 - acryloyloxy - 2 - hydroxybenzophenone and ethanol at a mass ratio of 1:20 - 22, stir at 200 - 300 r / min at room temperature for 5 - 7 min, add octa - aminopropylcage - like polyhedral oligomeric silsesquioxane in an equimolar amount to 4 - acryloyloxy - 2 - hydroxybenzophenone, raise the temperature to 45 - 55 °C, and continue to stir for 3.5 - 4.5 h under argon protection. Filter, wash with ethanol 3 - 5 times, and dry to obtain modified cage - like polyhedral oligomeric silsesquioxane;

[0011] (2) Mix pre - modified quartz sand, maleic anhydride and N,N - dimethylformamide at a mass ratio of 3 - 5:1:16 - 18, stir at 85 - 95 °C and 200 - 300 r / min under nitrogen protection for 25 - 35 min, add a mixed solution that is 1.8 - 2.2 times the mass of maleic anhydride, continue to stir for 35 - 45 min, cool to room temperature, pour it into deionized water at 0 - 4 °C, continue to stir for 11 - 13 h, filter, and dry at 75 - 85 °C for 9 - 11 h to obtain modified quartz sand;

[0012] (3) Immerse pre - modified epoxy polymer in a mixed solution of N - (trifluoromethylthio) phthalimide, carry out ultraviolet light irradiation reaction, take it out, immerse it in deionized water, ultrasonic for 10 - 20 min, and dry it under vacuum at - 10 - 0 °C for 22 - 24 h to obtain modified epoxy polymer;

[0013] (4) Let the asphalt stand at 130 - 140 °C for 10 - 20 min, sequentially add modified quartz sand, modified epoxy polymer and modified cage - like polyhedral oligomeric silsesquioxane, stir at 700 - 900 r / min for 35 - 45 min, cool the temperature to 85 - 95 °C, and stand for 35 - 45 min to obtain asphalt mortar.

[0014] As an optimization, the specific operation of the drying in step (1) is vacuum drying at - 10 - 0 °C for 22 - 26 h.

[0015] As an optimization, the pre - modified quartz sand in step (2) is prepared by mixing quartz sand, 3 - aminopropyltrimethoxysilane and isopropanol at a mass ratio of 3 - 5:1 - 2:30 - 50, stirring at 85 - 95 °C and 200 - 300 r / min for 5 - 7 h, centrifuging, taking the solid, washing with deionized water 3 - 5 times, and drying at 90 - 100 °C for 2 - 4 h.

[0016] As an optimization, the quartz sand is 20 - mesh quartz sand.

[0017] As an optimization, the mixed solution in step (2) is prepared by mixing nickel acetate tetrahydrate, triethylamine and acetic anhydride evenly at a mass ratio of 0.001:0.3 - 0.4:40 - 45.

[0018] As an optimization, the pre-modified epoxy polymer described in step (3) is prepared by mixing glycidyl methacrylate, N,N-dimethylallylamine, 2-allylfuran, azobisisobutyronitrile and tetrahydrofuran in a mass ratio of 7-8:1:1-2:0.03-0.05:30-40, stirring at 200-300 r / min, 60-70 °C under nitrogen protection for 10-12 h, cooling to room temperature, pouring into methanol, standing for 3-5 h, filtering, and drying in vacuo at 55-65 °C for 22-26 h.

[0019] As an optimization, the N-(trifluoromethylthio)phthalimide mixed solution described in step (3) is prepared by mixing N-(trifluoromethylthio)phthalimide, acetonitrile and benzophenone evenly in a mass ratio of 7-8:49-53:0.5-1.

[0020] As an optimization, the specific operation of the ultraviolet light irradiation reaction described in step (3) is to place it in a closed photoreactor under nitrogen protection, and use a 40 W purple LED lamp with a wavelength of 370 nm for lamp irradiation for 48-50 h.

[0021] As an optimization, the composition ratio of the raw materials of the asphalt mortar prepared in step (4) is specifically asphalt: modified epoxy polymer: modified quartz sand: modified cage-like polyhedral oligomeric silsesquioxane in a mass ratio of 8-10:1.8-2.2:2.6-3:0.6-0.8.

[0022] The asphalt is No. 70 A-grade road asphalt, and the purchasing manufacturer is Xingtai Jiheng Technology Co., Ltd.

[0023] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0024] When preparing the modified asphalt mortar for road repair, the present invention reacts 4-acryloxy-2-hydroxybenzophenone with octaaminopropyl cage-like polyhedral oligomeric silsesquioxane to obtain modified cage-like polyhedral oligomeric silsesquioxane; reacts quartz sand with 3-aminopropyltrimethoxysilane and maleic anhydride in sequence to obtain modified quartz sand; polymerizes glycidyl methacrylate, N,N-dimethylallylamine, 2-allylfuran and then reacts with N-(trifluoromethylthio)phthalimide to obtain modified epoxy polymer; heats asphalt and mixes it with modified epoxy polymer, modified quartz sand and modified cage-like polyhedral oligomeric silsesquioxane to obtain the modified asphalt mortar for road repair.

[0025] First, 4-propyleneoxy-2-hydroxybenzophenone is reacted with octaaminopropyl caged polysilsesquioxane to obtain a modified caged polysilsesquioxane; the octaaminopropyl caged polysilsesquioxane can form a tight, high-density hard coating to prevent liquid from penetrating into the interior of the material and enhance the waterproof ability of the material; and the surface of the octaaminopropyl caged polysilsesquioxane is rich in aminopropyl groups, which reacts with epoxy groups to play a curing agent effect. The introduction of the octaaminopropyl caged polysilsesquioxane increases the cross-linking point density of the material, so that the material can better resist deformation and damage at high temperatures, thereby improving its heat resistance, and the octaaminopropyl caged polysilsesquioxane itself has high heat resistance, and its initial thermal decomposition temperature can reach more than 350°C, which can effectively improve the heat resistance of the material; and the introduction of 4-propyleneoxy-2-hydroxybenzophenone through the reaction of amino groups and alkenes can absorb ultraviolet rays, and by absorbing ultraviolet light and converting it into heat energy, the effect of protecting the material from damage by ultraviolet rays is achieved, thereby improving the aging resistance of the material.

[0026] Secondly, quartz sand is reacted with 3-aminopropyltrimethoxysilane and maleic anhydride in sequence to obtain modified quartz sand; glycidyl methacrylate, N,N-dimethylpropyleneamine, and 2-allylfuran are polymerized and then reacted with N-(trifluoromethylthio)phthalimide to obtain a modified epoxy polymer; the asphalt is heated and mixed with the modified epoxy polymer, modified quartz sand, and modified caged polysilsesquioxane to obtain modified asphalt mortar for road repair; furan groups and maleimide groups are introduced into the asphalt mortar, and reversible bonds are generated through the DA reaction between the two to achieve a self-healing effect; fluorine is added to the asphalt surface through the reaction with N-(trifluoromethylthio)phthalimide. The electronegativity of the fluorine atom is very large, so that the electron cloud in the carbon-fluorine bond is biased towards the fluorine atom, resulting in the carbon-fluorine bond having a very high bond energy, which is very stable and not easily destroyed by water or other chemicals, thereby enhancing the material's waterproof ability. DETAILED DESCRIPTION

[0027] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0028] Embodiment 1: A method for preparing modified asphalt mortar for road repair, mainly comprising the following preparation steps:

[0029] (1) Mix 4 - acryloxy - 2 - hydroxybenzophenone and ethanol at a mass ratio of 1:20, stir at 200 r / min at room temperature for 5 min, add octa - aminopropylcage - like polyhedral oligomeric silsesquioxane in an equimolar amount to 4 - acryloxy - 2 - hydroxybenzophenone, heat to 45 °C, and continue stirring for 3.5 h under argon protection. Filter, wash with ethanol 3 times, and vacuum - dry at - 10 °C for 22 h to obtain modified cage - like polyhedral oligomeric silsesquioxane;

[0030] (2) Mix nickel acetate tetrahydrate, triethylamine, and acetic anhydride evenly at a mass ratio of 0.001:0.3:40 to obtain a mixed solution; mix quartz sand, 3 - aminopropyltrimethoxysilane, and isopropanol at a mass ratio of 3:1:30, stir at 85 °C and 200 r / min for 5 h, centrifuge, take the solid, wash with deionized water 3 times, and dry at 90 °C for 2 h to obtain pre - modified quartz sand; mix the pre - modified quartz sand, maleic anhydride, and N,N - dimethylformamide at a mass ratio of 3:1:16, stir at 85 °C and 200 r / min under nitrogen protection for 25 min, add the mixed solution that is 1.8 times the mass of maleic anhydride, continue stirring for 35 min, cool to room temperature, pour into deionized water at 0 °C, continue stirring for 11 h, filter, and dry at 75 °C for 9 h to obtain modified quartz sand;

[0031] (3) Mix glycidyl methacrylate, N,N - dimethylallylamine, 2 - allylfuran, azobisisobutyronitrile, and tetrahydrofuran at a mass ratio of 7:1:1:0.03:30, stir at 200 r / min at 60 °C under nitrogen protection for 10 h, cool to room temperature, pour into methanol, let stand for 3 h, filter, and vacuum - dry at 55 °C for 22 h to obtain pre - modified epoxy polymer; mix N - (trifluoromethylthio)phthalimide, acetonitrile, and benzophenone evenly at a mass ratio of 7:49:0.5 to obtain an N - (trifluoromethylthio)phthalimide mixed solution; immerse the pre - modified epoxy polymer in the N - (trifluoromethylthio)phthalimide mixed solution, place it in a closed photoreactor under nitrogen protection, irradiate with a 40 W purple LED lamp with a wavelength of 370 nm for 48 h, take it out, immerse it in deionized water, ultrasonicate for 10 min, and vacuum - dry at - 10 °C under vacuum conditions for 22 h to obtain modified epoxy polymer;

[0032] (4) Take 8 parts of 70# A - grade road asphalt A, 1.8 parts of modified epoxy polymer, 2.6 parts of modified quartz sand, and 0.6 parts of modified cage - like polyhedral oligomeric silsesquioxane by mass. Let the 70# A - grade road asphalt stand at 130 °C for 10 min, and sequentially add the modified quartz sand, modified epoxy polymer, and modified cage - like polyhedral oligomeric silsesquioxane, stir at 700 r / min for 35 min, cool to 85 °C, and let stand for 35 min to obtain asphalt mortar.

[0033] Example 2: A preparation method of modified asphalt mortar for road repair mainly includes the following preparation steps:

[0034] (1) Mix 4 - acryloxy - 2 - hydroxybenzophenone and ethanol at a mass ratio of 1:21, stir at 250 r / min at room temperature for 6 min, add octa - aminopropylcage - like polyhedral oligomeric silsesquioxane in an equimolar amount to 4 - acryloxy - 2 - hydroxybenzophenone, raise the temperature to 50 °C, and continue to stir for 4 h under argon protection. Filter, wash 4 times with ethanol, and vacuum - dry at - 5 °C for 24 h to obtain modified cage - like polyhedral oligomeric silsesquioxane;

[0035] (2) Mix nickel acetate tetrahydrate, triethylamine, and acetic anhydride evenly at a mass ratio of 0.001:0.35:42.5 to obtain a mixed solution; mix quartz sand, 3 - aminopropyltrimethoxysilane, and isopropanol at a mass ratio of 4:1.5:40, stir at 90 °C and 250 r / min for 6 h, centrifuge, take the solid, wash 4 times with deionized water, and dry at 95 °C for 3 h to obtain pre - modified quartz sand; mix the pre - modified quartz sand, maleic anhydride, and N,N - dimethylformamide at a mass ratio of 4:1:17, stir at 90 °C and 250 r / min under nitrogen protection for 30 min, add the mixed solution twice the mass of maleic anhydride, continue to stir for 40 min, cool to room temperature, pour into deionized water at 2 °C, continue to stir for 12 h, filter, and dry at 80 °C for 10 h to obtain modified quartz sand;

[0036] (3) Mix glycidyl methacrylate, N,N - dimethylallylamine, 2 - allylfuran, azobisisobutyronitrile, and tetrahydrofuran at a mass ratio of 7.5:1:1.5:0.04:35, stir at 250 r / min at 65 °C under nitrogen protection for 11 h, cool to room temperature, pour into methanol, let stand for 4 h, filter, and vacuum - dry at 60 °C for 24 h to obtain pre - modified epoxy polymer; mix N - (trifluoromethylthio)phthalimide, acetonitrile, and benzophenone evenly at a mass ratio of 7.5:51:0.75 to obtain an N - (trifluoromethylthio)phthalimide mixed solution; immerse the pre - modified epoxy polymer in the N - (trifluoromethylthio)phthalimide mixed solution, place it in a closed photoreactor under nitrogen protection, irradiate with a 40 W purple LED lamp with a wavelength of 370 nm for 49 h, take it out, immerse it in deionized water, ultrasonicate for 15 min, and dry at - 5 °C under vacuum conditions for 23 h to obtain modified epoxy polymer;

[0037] (4)Take 9 parts of 70# Class A road asphalt A, 2 parts of modified epoxy polymer, 2.8 parts of modified quartz sand, and 0.7 parts of modified cage-like polyhedral oligomeric silsesquioxane by mass fraction. Let the 70# Class A road asphalt stand still at 135 °C for 15 min, and then successively add the modified quartz sand, modified epoxy polymer, and modified cage-like polyhedral oligomeric silsesquioxane, and stir at 800 r / min for 40 min. Cool down to 90 °C and stand still for 40 min to obtain the asphalt mortar.

[0038] Example 3: A preparation method of a modified asphalt mortar for road repair mainly includes the following preparation steps:

[0039] (1)Mix 4 - allyloxy - 2 - hydroxybenzophenone and ethanol in a mass ratio of 1:22, stir at 300 r / min at room temperature for 7 min, add octa - aminopropyl cage - like polyhedral oligomeric silsesquioxane with an equimolar amount of 4 - allyloxy - 2 - hydroxybenzophenone, raise the temperature to 55 °C, and continue to stir for 4.5 h under argon protection. Filter, wash with ethanol 5 times, and vacuum dry at 0 °C for 26 h to obtain the modified cage - like polyhedral oligomeric silsesquioxane;

[0040] (2)Mix nickel acetate tetrahydrate, triethylamine, and acetic anhydride evenly in a mass ratio of 0.001:0.4:45 to obtain a mixed solution; mix quartz sand, 3 - aminopropyltrimethoxysilane, and isopropanol in a mass ratio of 5:2:50, stir at 95 °C and 300 r / min for 7 h, centrifuge, take the solid, wash with deionized water 5 times, and dry at 100 °C for 4 h to obtain pre - modified quartz sand; mix the pre - modified quartz sand, maleic anhydride, and N,N - dimethylformamide in a mass ratio of 5:1:18, stir at 95 °C and 300 r / min under nitrogen protection for 35 min, add the mixed solution with a mass 2.2 times that of maleic anhydride, continue to stir for 45 min, cool to room temperature, pour it into deionized water at 4 °C, continue to stir for 13 h, filter, and dry at 85 °C for 11 h to obtain the modified quartz sand;

[0041] (3) Mix glycidyl methacrylate, N,N-dimethylallylamine, 2-allylfuran, azobisisobutyronitrile and tetrahydrofuran in a mass ratio of 8:1:2:0.05:40, stir at 300 r / min, 70 °C under nitrogen protection for 12 h, cool to room temperature, pour into methanol, let stand for 5 h, filter, and dry in vacuum at 65 °C for 26 h to obtain pre-modified epoxy polymer; Mix N-(trifluoromethylthio)phthalimide, acetonitrile and benzophenone in a mass ratio of 8:53:1 evenly to obtain N-(trifluoromethylthio)phthalimide mixed solution; Immerse the pre-modified epoxy polymer in the N-(trifluoromethylthio)phthalimide mixed solution, place it in a closed photoreactor under nitrogen protection, use a 40 W purple LED lamp with a wavelength of 370 nm, irradiate for 50 h, take out, immerse in deionized water, ultrasonicate for 20 min, and dry in vacuum at 0 °C for 24 h to obtain modified epoxy polymer;

[0042] (4) Take 10 parts of 70# A-grade road asphalt A, 2.2 parts of modified epoxy polymer, 3 parts of modified quartz sand, and 0.8 parts of modified cage-like polyhedral oligomeric silsesquioxane by mass. Let the 70# A-grade road asphalt stand at 140 °C for 20 min, and successively add modified quartz sand, modified epoxy polymer and modified cage-like polyhedral oligomeric silsesquioxane, stir at 900 r / min for 45 min, cool to 95 °C, and let stand for 45 min to obtain asphalt mortar.

[0043] Comparative Example 1:

[0044] A preparation method of modified asphalt mortar for road repair mainly includes the following preparation steps:

[0045] (1) Mix nickel acetate tetrahydrate, triethylamine and acetic anhydride in a mass ratio of 0.001:0.35:42.5 evenly to obtain a mixed solution; Mix quartz sand, 3-aminopropyltrimethoxysilane and isopropanol in a mass ratio of 4:1.5:40, stir at 90 °C, 250 r / min for 6 h, centrifuge, take the solid, wash with deionized water 4 times, and dry at 95 °C for 3 h to obtain pre-modified quartz sand; Mix the pre-modified quartz sand, maleic anhydride and N,N-dimethylformamide in a mass ratio of 4:1:17, stir at 90 °C, 250 r / min under nitrogen protection for 30 min, add the mixed solution twice the mass of maleic anhydride, continue to stir for 40 min, cool to room temperature, pour into deionized water at 2 °C, continue to stir for 12 h, filter, and dry at 80 °C for 10 h to obtain modified quartz sand;

[0046] (2) Mix glycidyl methacrylate, N,N-dimethylacrylamide, 2-allylfuran, azobisisobutyronitrile and tetrahydrofuran in a mass ratio of 7.5:1:1.5:0.04:35, stir at 250 r / min, 65 °C under nitrogen protection for 11 h, cool to room temperature, pour into methanol, let stand for 4 h, filter, and dry in vacuum at 60 °C for 24 h to obtain pre-modified epoxy polymer; Mix N-(trifluoromethylthio)phthalimide, acetonitrile and benzophenone in a mass ratio of 7.5:51:0.75 evenly to obtain a mixed solution of N-(trifluoromethylthio)phthalimide; Immerse the pre-modified epoxy polymer in the mixed solution of N-(trifluoromethylthio)phthalimide, place it in a closed photoreactor under nitrogen protection, irradiate with a 40 W purple LED lamp with a wavelength of 370 nm for 49 h, take out, immerse in deionized water, ultrasonicate for 15 min, and dry in vacuum at -5 °C for 23 h to obtain modified epoxy polymer;

[0047] (3) Take 9 parts of 70# A-grade road asphalt A, 2 parts of modified epoxy polymer, 2.8 parts of modified quartz sand, and 0.7 part of 1,4-butanediamine by mass. Let the 70# A-grade road asphalt stand at 135 °C for 15 min, and sequentially add modified quartz sand, modified epoxy polymer and 1,4-butanediamine, stir at 800 r / min for 40 min, cool down to 90 °C, and let stand for 40 min to obtain asphalt mortar.

[0048] Comparative Example 2:

[0049] A preparation method of modified asphalt mortar for road repair mainly includes the following preparation steps:

[0050] (1) Mix 4-propenyloxy-2-hydroxybenzophenone and ethanol in a mass ratio of 1:21, stir at 250 r / min at room temperature for 6 min, add octaaminopropylcage-like polyhedral oligomeric silsesquioxane in an equimolar amount of 4-propenyloxy-2-hydroxybenzophenone, heat up to 50 °C, and continue to stir for 4 h under argon protection, filter, wash with ethanol 4 times, and dry in vacuum at -5 °C for 24 h to obtain modified cage-like polyhedral oligomeric silsesquioxane;

[0051] (2) Glycidyl methacrylate, N,N-dimethylacrylamide, 2-allylfuran, azobisisobutyronitrile and tetrahydrofuran were mixed in a mass ratio of 7.5:1:1.5:0.04:35, stirred at 250 r / min, 65 °C under nitrogen protection for 11 h, cooled to room temperature, poured into methanol, allowed to stand for 4 h, filtered, and vacuum dried at 60 °C for 24 h to obtain a pre-modified epoxy polymer; N-(trifluoromethylthio)phthalimide, acetonitrile and benzophenone were mixed evenly in a mass ratio of 7.5:51:0.75 to obtain a mixed solution of N-(trifluoromethylthio)phthalimide; the pre-modified epoxy polymer was immersed in the mixed solution of N-(trifluoromethylthio)phthalimide, placed in a closed photoreactor under nitrogen protection, irradiated with a 40 W purple LED lamp with a wavelength of 370 nm for 49 h, taken out, immersed in deionized water, sonicated for 15 min, and dried under vacuum at -5 °C for 23 h to obtain a modified epoxy polymer;

[0052] (3) 9 parts of No. 70 A-grade road asphalt A, 2 parts of modified epoxy polymer, 2.8 parts of quartz sand, and 0.7 part of modified cage-like polyhedral oligomeric silsesquioxane were taken by mass. The No. 70 A-grade road asphalt was allowed to stand at 135 °C for 15 min, and quartz sand, modified epoxy polymer and modified cage-like polyhedral oligomeric silsesquioxane were added in sequence, stirred at 800 r / min for 40 min, cooled to 90 °C, and allowed to stand for 40 min to obtain asphalt mortar.

[0053] Comparative Example 3:

[0054] A preparation method of a modified asphalt mortar for road repair mainly includes the following preparation steps:

[0055] (1) 4-Acryloxy-2-hydroxybenzophenone and ethanol were mixed in a mass ratio of 1:21, stirred at 250 r / min at room temperature for 6 min, octaaminopropyl cage-like polyhedral oligomeric silsesquioxane with an equimolar amount of 4-acryloxy-2-hydroxybenzophenone was added, the temperature was raised to 50 °C, and stirring was continued for 4 h under argon protection, filtered, washed 4 times with ethanol, and vacuum dried at -5 °C for 24 h to obtain a modified cage-like polyhedral oligomeric silsesquioxane;

[0056] (2) Mix nickel acetate tetrahydrate, triethylamine, and acetic anhydride evenly according to a mass ratio of 0.001:0.35:42.5 to obtain a mixed solution; mix quartz sand, 3-aminopropyltrimethoxysilane, and isopropanol according to a mass ratio of 4:1.5:40, stir at 90 °C and 250 r / min for 6 h, centrifuge, take the solid, wash it 4 times with deionized water, and dry it at 95 °C for 3 h to obtain pre-modified quartz sand; mix the pre-modified quartz sand, maleic anhydride, and N,N-dimethylformamide according to a mass ratio of 4:1:17, stir at 90 °C and 250 r / min under nitrogen protection for 30 min, add the mixed solution twice the mass of maleic anhydride, continue stirring for 40 min, cool to room temperature, pour it into deionized water at 2 °C, continue stirring for 12 h, filter, and dry at 80 °C for 10 h to obtain modified quartz sand;

[0057] (3) Mix glycidyl methacrylate, N,N-dimethylallylamine, 2-allylfuran, azobisisobutyronitrile, and tetrahydrofuran according to a mass ratio of 7.5:1:1.5:0.04:35, stir at 250 r / min, 65 °C under nitrogen protection for 11 h, cool to room temperature, pour it into methanol, let it stand for 4 h, filter, and vacuum dry at 60 °C for 24 h to obtain pre-modified epoxy polymer;

[0058] (4) Take 9 parts of 70# A-grade road asphalt A, 2 parts of pre-modified epoxy polymer, 2.8 parts of modified quartz sand, and 0.7 part of modified cage-like polyhedral oligomeric silsesquioxane by mass. Let the 70# A-grade road asphalt stand at 135 °C for 15 min, and sequentially add the modified quartz sand, pre-modified epoxy polymer, and modified cage-like polyhedral oligomeric silsesquioxane, stir at 800 r / min for 40 min, cool down to 90 °C, and let it stand for 40 min to obtain asphalt mortar.

[0059] Test Example 1:

[0060] Aging resistance and self-healing test:

[0061] Self-healing test: Let the asphalt mortar prepared in each example and comparative example stand at 150 °C for 2 h. Referring to the requirements of GB / T2568-1995, make the asphalt mortar prepared in each example and comparative example into standard dumbbell-shaped specimens, test the tensile strength, and record it as the initial tensile strength; then cut a small slit with a length of 3 mm and a depth of 3 mm at the middle position of the same specimen, align and join the fracture surfaces after cutting, place it in a constant-temperature oven at 145 °C for 2 h, and test the tensile strength of the repaired specimen, and record it as the tensile strength after self-healing; calculate the self-healing efficiency, where the self-healing efficiency = tensile strength after self-healing / initial tensile strength × 100%;

[0062] Aging resistance test: The asphalt mortars prepared in each example and comparative example were left standing at 150 °C for 2 h. Referring to the requirements of GB / T 2568-1995, the asphalt mortars prepared in each example and comparative example were made into standard dumbbell-shaped specimens, and the tensile strength was tested and recorded as the initial tensile strength; the same specimens were irradiated under a fluorescent ultraviolet lamp UV-A340 for 15 days, and the tensile strength was tested again and recorded as the tensile strength after aging; the tensile strength retention rate was calculated, where the tensile strength retention rate = tensile strength after aging / initial tensile strength × 100%. The results are shown in Table 1.

[0063] Table 1

[0064]

[0065] From the comparison of the experimental data in Table 1, it can be found that the modified asphalt mortar for road repair prepared by the present invention has good aging resistance and self-healing ability.

[0066] From the comparison of the experimental data of Examples 1, 2, 3 and Comparative Example 1 in Table 1, it can be found that the tensile strength retention rates of Examples 1, 2, 3 are larger than those of Comparative Example 1, indicating that the introduction of 4-propenyloxy-2-hydroxybenzophenone can absorb ultraviolet light, and by absorbing ultraviolet light and converting it into heat energy, the effect of protecting the material from ultraviolet damage can be achieved, and the aging resistance of the material can be improved;

[0067] From the comparison of the experimental data of Examples 1, 2, 3 and Comparative Example 2, it can be found that the self-healing efficiency of Examples 1, 2, 3 is larger than that of Comparative Example 2, indicating that the introduction of furan groups and maleimide groups into the asphalt mortar can generate reversible bonds through the DA reaction between the two, achieving a self-healing effect.

[0068] Test Example 2:

[0069] High temperature resistance test: The asphalt mortars prepared in each example and comparative example were left standing at 150 °C for 2 h, crushed to 30 mesh, 8 mg of asphalt was taken and placed in a crucible and then placed in a TG experimental instrument, and the mass retention rate at 300 °C was tested, where the mass retention rate = mass at 300 °C / 8 mg × 100%. The results are shown in Table 2.

[0070] Table 2

[0071]

[0072] From the comparison of the experimental data in Table 2, it can be found that the modified asphalt mortar for road repair prepared by the present invention has good high temperature resistance.

[0073] From the comparison of the experimental data of Examples 1, 2, 3 and Comparative Example 1 in Table 2, it can be found that the mass retention rates of Examples 1, 2, 3 are larger than that of Comparative Example 1, indicating that the surface of octa(aminopropyl)silsesquioxane is rich in aminopropyl groups, which react with epoxy groups to play the role of a curing agent. The introduction of octa(aminopropyl)silsesquioxane increases the crosslinking point density of the material, enabling the material to better resist deformation and damage at high temperatures, thereby improving its heat resistance. Moreover, octa(aminopropyl)silsesquioxane itself has high heat resistance, and its initial thermal decomposition temperature can reach above 350 °C, which can effectively improve the heat resistance of the material.

[0074] Test Example 3:

[0075] Waterproof test:

[0076] The asphalt mortars prepared in each example and comparative example were left standing at 150 °C for 2 h to make specimens of 4 cm × 4 cm × 0.1 cm, and the water surface contact angle was measured using a JC2000DM type optical contact angle measuring instrument. The results are shown in Table 3.

[0077] Table 3

[0078]

[0079] From the comparison of the experimental data in Table 3, it can be found that the modified asphalt mortar for road repair prepared by the present invention has good waterproof ability.

[0080] From the comparison of the experimental data of Examples 1, 2, 3 and Comparative Example 1 in Table 3, it can be found that the water contact angles of Examples 1, 2, 3 are larger than that of Comparative Example 1, indicating that octa(aminopropyl)silsesquioxane can form a dense and high-density hard coating film to prevent liquid from penetrating into the material interior and enhance the waterproof ability of the material;

[0081] From the comparison of the experimental data of Examples 1, 2, 3 and Comparative Example 3, it can be found that the water contact angles of Examples 1, 2, 3 are larger than that of Comparative Example 3, indicating that fluorine is introduced onto the asphalt surface through the reaction with N-(trifluoromethylthio)phthalimide. The electronegativity of fluorine atoms is very large, causing the electron cloud in the carbon-fluorine bond to deviate towards the fluorine atoms, resulting in a very high bond energy for the carbon-fluorine bond, which is very stable and not easily damaged by water or other chemical substances, enhancing the waterproof ability of the material.

[0082] The specific embodiments described above further elaborate on the purpose, technical solutions and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for preparing modified asphalt mortar for road repair, characterized in that: The preparation method of the modified asphalt mortar for road repair mainly includes the following preparation steps: (1) 4-propyleneoxy-2-hydroxybenzophenone and ethanol were mixed in a mass ratio of 1:20-22, stirred at 200-300 r / min and room temperature for 5-7 min, and an equal molar amount of octaaminopropyl caged polysilsesquioxane of 4-propyleneoxy-2-hydroxybenzophenone was added, the temperature was raised to 45-55°C, and stirring was continued for 3.5-4.5 h under argon protection, filtered, washed with ethanol 3-5 times, and dried to obtain a modified caged polysilsesquioxane; (2) Quartz sand, 3-aminopropyltrimethoxysilane and isopropanol were mixed in a mass ratio of 3-5:1-2:30-50, stirred at 85-95°C and 200-300 r / min for 5-7 h, centrifuged, and the solid was taken out. The solid was washed with deionized water for 3-5 times and dried at 90-100°C for 2-4 h to obtain pre-modified quartz sand; nickel acetate tetrahydrate, triethylamine and acetic anhydride were mixed in a mass ratio of 0.001:0.3-0.4:40-45 to obtain a mixed solution; the pre-modified Modified quartz sand, maleic anhydride and N,N-dimethylformamide are mixed in a mass ratio of 3-5:1:16-18, stirred for 25-35 min at 85-95°C, 200-300 r / min, and under nitrogen protection, a mixed solution of 1.8-2.2 times the mass of maleic anhydride is added, and stirring is continued for 35-45 min. The mixture is cooled to room temperature, poured into deionized water at 0-4°C, and stirring is continued for 11-13 h. The mixture is filtered and dried at 75-85°C for 9-11 h to obtain modified quartz sand. (3) N-(trifluoromethylthio)phthalimide, acetonitrile and benzophenone were mixed uniformly in a mass ratio of 7-8:49-53:0.5-1 to prepare a N-(trifluoromethylthio)phthalimide mixed solution; glycidyl methacrylate, N,N-dimethylpropyleneamine, 2-allylfuran, azobisisobutyronitrile and tetrahydrofuran were mixed in a mass ratio of 7-8:1:1-2:0.03-0.05:30-40, and the mixture was stirred at 200-300 r / min, 60- 70°C, stirring for 10-12 hours under nitrogen protection, cooling to room temperature, pouring into methanol, standing for 3-5 hours, filtering, and vacuum drying at 55-65°C for 22-26 hours to obtain a pre-modified epoxy polymer; immersing the pre-modified epoxy polymer in a mixed solution of N-(trifluoromethylthio)phthalimide, irradiating with ultraviolet light for reaction, taking out, immersing in deionized water, ultrasonicating for 10-20 minutes, and drying at -10-0°C under vacuum conditions for 22-24 hours to obtain a modified epoxy polymer; (4) Allow the asphalt to stand at 130-140°C for 10-20 min, then mix the asphalt, modified epoxy polymer, modified quartz sand and modified cage-like polysilsesquioxane in a mass ratio of 8-10:1.8-2.2:2.6-3:0.6-0.8, stir at 700-900 r / min for 35-45 min, cool to 85-95°C, and allow to stand for 35-45 min to obtain asphalt mortar.

2. The method for preparing a modified asphalt mortar for road repair according to claim 1, characterized in that: The specific operation of the drying in step (1) is vacuum drying at -10~0°C for 22~26h.

3. The method for preparing a modified asphalt mortar for road repair according to claim 1, characterized in that: The specific operation of the ultraviolet light irradiation reaction in step (3) is to place the reaction mixture in a closed photoreactor under nitrogen protection and irradiate it with a 40W purple LED lamp with a wavelength of 370nm for 48 to 50 hours.

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