Water-damage-resistant asphalt modifier based on dynamic crosslinking, and preparation method therefor and use thereof

Abstract

The present invention relates to the technical field of asphalt modifiers, and specifically relates to a water-damage-resistant asphalt modifier based on dynamic crosslinking, and a preparation method therefor and the use thereof. The method comprises the following steps: mixing a substance containing glass fiber reinforced plastic with a silane hydrolysate, and drying the mixture to obtain a silanization product; mechanically blending the silanization product with an elastomer, and crushing same to obtain a rubber-coated silanization product; mixing the rubber-coated silanization product with sulfur, so as to obtain a water-damage-resistant asphalt modifier based on dynamic crosslinking, wherein the silane hydrolysate is a solution obtained by mixing a silane coupling agent, water and absolute ethyl alcohol. The water-damage-resistant asphalt modifier based on dynamic crosslinking prepared in the present invention is used for preparing modified asphalt, and the modified asphalt is used for preparing a modified asphalt mixture, such that the modified asphalt mixture has a good working performance and pavement performance, particularly good water damage resistance, and significant economic, environmental and social benefits.

Description

A dynamic cross-linking-based water-damage-resistant asphalt modifier and its preparation method and application

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of Chinese patent application No. 202311092894.7 filed on August 28, 2023, the contents of which are incorporated herein by reference. Technical Field

[0003] The present invention relates to the technical field of asphalt modifiers, and specifically to a dynamic cross-linking-based water-damage-resistant asphalt modifier, a preparation method and application thereof, and especially to a dynamic cross-linking-based water-damage-resistant asphalt modifier, a preparation method thereof, modified asphalt and a modified asphalt mixture, and a preparation method thereof. Background Art

[0004] FRP is a thermosetting composite material with glass fiber as the reinforcement material and epoxy resin, unsaturated polyester resin and polyurethane resin as the matrix resin. Waste FRP refers to composite materials such as waste scraps and substandard products generated during the production, transportation, sales and use of FRP-related industrial enterprises, as well as composite materials that need to be disposed of due to damage and scrapping during the working period or scrap period due to failure to meet the working performance requirements. Traditional methods of handling waste FRP include landfill and burning, but these practices occupy a large amount of land resources, cause serious groundwater and air pollution, and do not fully utilize the residual mechanical properties and value of the composite materials. Faced with the large amount of waste FRP in the future, its resource utilization and high-value reuse has become a difficult problem that the industry generally pays attention to. Therefore, it is of great significance to develop a low-cost and high-efficiency method for recycling waste FRP and make it into high-value-added products that meet performance requirements.

[0005] In order to improve the quality of asphalt pavements and extend their lifespan, the international community proposed the use of SBS modified asphalt for pavement construction in the 1990s. SBS is a thermoplastic copolymer with a triblock structure formed by the polymerization reaction of butadiene and styrene, and is divided into two types: linear and star structures. Under room temperature conditions, the polystyrene hard segments (PS segments) in the SBS macromolecular structure will aggregate with each other to form physical crosslinking points due to their high cohesive energy, making SBS exhibit rubber elasticity. Based on the unique structural characteristics and performance advantages of SBS, its use in asphalt modification can significantly improve the asphalt's low-temperature cracking resistance and high-temperature rutting resistance. Therefore, SBS modified asphalt has been widely used in high-grade highway construction.

[0006] Due to the high price of SBS, the cost of road construction remains high. In recent years, some research has been carried out on how to use new materials at low cost and high quality to reduce the use of high-cost SBS modifiers while ensuring that the durability of asphalt pavement is not affected. However, the ideal asphalt modified material has not yet appeared.

[0007] Summary of the Invention

[0008] The purpose of the present invention is to address the defects in the prior art that waste materials containing fiberglass are difficult to be utilized as high-value resources, and there is currently no asphalt modifier that has the advantages of both high quality and low cost. Therefore, a dynamic cross-linking-based water-damage-resistant asphalt modifier and its preparation method and application are proposed. The method first uses a hydrolyzate containing a silane coupling agent to react with a substance containing fiberglass to increase the non-polar groups on the surface of the fiberglass, and then melts and mixes the reaction product with rubber to achieve chemical coating modification. Finally, the modified product is mixed with sulfur to obtain a dynamic cross-linking-based water-damage-resistant asphalt modifier. Using the dynamic cross-linking-based water-damage-resistant asphalt modifier prepared by the present invention to prepare modified asphalt and using the modified asphalt to prepare a modified asphalt mixture can make it have good working performance and road performance, especially outstanding water damage resistance, with significant economic, environmental and social benefits.

[0009] The first aspect of the present invention provides a method for preparing a dynamic cross-linking-based water-damage resistant asphalt modifier, the method comprising the following steps:

[0010] (1) mixing the material containing glass fiber reinforced plastic with the silane hydrolyzate and drying;

[0011] (2) mechanically blending the product obtained in step (1) with an elastomer, crushing, and sieving;

[0012] (3) mixing the product obtained in step (2) with sulfur to obtain a dynamic cross-linking-based water-damage resistant asphalt modifier, wherein the silane hydrolyzate is obtained by mixing a silane coupling agent, water and anhydrous ethanol.

[0013] Preferably, the mass ratio of the elastomer to the sulfur is 100:(1.5-5).

[0014] Preferably, in step (1), the mass ratio of the fiberglass-containing material to the silane coupling agent in the silane hydrolyzate is 100:(10-20).

[0015] Preferably, in step (2), the mass ratio of the product obtained in step (1) to the amount of the elastomer is 100:(15-45).

[0016] Preferably, in step (1), the mixing conditions include: temperature of 55-85° C. and time of 10-60 min.

[0017] Preferably, in step (1), the particle size of the fiberglass-containing material is ≤0.3 mm.

[0018] Preferably, in step (2), the mechanical blending conditions include: temperature of 50-70° C. and time of 15-40 min.

[0019] Preferably, in step (2), the elastomer is selected from one or more of styrene-butadiene rubber, styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, hydrogenated styrene-butadiene-styrene copolymer, butyl rubber and ethylene-vinyl acetate copolymer.

[0020] Preferably, in step (2), the crushing is freeze crushing.

[0021] Preferably, the particle size of the product obtained in step (2) is ≤0.3 mm.

[0022] Preferably, the mass ratio of the silane coupling agent, the water and the anhydrous ethanol is (14-19):(6-11):100.

[0023] Preferably, the silane coupling agent is selected from one or more of γ-aminopropyltriethoxysilane, γ-(2,3-epoxypropyloxy)propyltrimethoxysilane and γ-methacryloxypropyltrimethoxysilane.

[0024] The second aspect of the present invention provides a dynamic cross-linking-based water-damage resistant asphalt modifier prepared by the method described above.

[0025] The third aspect of the present invention provides a method for preparing modified asphalt, which comprises mixing the above-mentioned dynamic cross-linking-based water damage resistance asphalt modifier with an optional SBS modifier and base asphalt.

[0026] Preferably, the weight ratio of the dynamically cross-linked anti-water damage asphalt modifier to the matrix asphalt is (1-20):100.

[0027] Preferably, the weight ratio of the total weight of the dynamically cross-linked anti-water damage asphalt modifier and the SBS modifier to the base asphalt is (1-20):100.

[0028] The fourth aspect of the present invention provides a modified asphalt prepared by the above-described method.

[0029] A fifth aspect of the present invention provides a method for preparing a modified asphalt mixture, comprising preheating the modified asphalt, aggregate and mineral powder described above, respectively, and then mixing the preheated modified asphalt, aggregate and mineral powder.

[0030] Preferably, the ratio of the weight of the modified asphalt to the total weight of the aggregate and the mineral powder is (4-6):100.

[0031] The sixth aspect of the present invention provides a modified asphalt mixture prepared by the method described above.

[0032] The dynamic cross-linking-based water-damage-resistant asphalt modifier of the present invention, its preparation method, and application have at least the following beneficial effects:

[0033] (1) The present invention provides a method for preparing a dynamic cross-linking anti-water damage asphalt modifier, which uses silanol groups generated by hydrolysis of a silane coupling agent to react with silanol groups on the surface of glass fibers in glass fiber reinforced plastics to increase the non-polar groups on the surface of the glass fiber reinforced plastics to obtain a silanized product. The silanized product is then mechanically blended with rubber to react with the non-polar groups on the surface of the rubber and the silanized product to achieve chemical coating modification to obtain a rubber-coated silanized product. The present invention uses a silane coupling agent and rubber to synergistically treat a substance containing glass fiber reinforced plastics, thereby improving the compatibility of the glass fiber reinforced plastics with asphalt.

[0034] (2) Sulfur is mixed and pre-embedded in the silanized rubber product to form a water-damage-resistant asphalt modifier based on dynamic cross-linking. When preparing the modified asphalt, the sulfur in the water-damage-resistant asphalt modifier can cause the silanized rubber product to be in-situ cross-linked in the matrix asphalt, thereby improving the high-temperature resistance of the asphalt while ensuring water stability. At the same time, the sulfur can be highly compatible with the environment of the asphalt mixing process (dynamic process) (about 150°C);

[0035] (3) Modifying asphalt with discarded wind turbine blades treated with silane coupling agents will not significantly affect its working performance. Using them in conjunction with sulfur and rubber to modify asphalt mixtures can significantly improve the water stability, high-temperature permanent deformation resistance, and flexural tensile properties of the asphalt mixture, thereby achieving a high-quality improvement in the road performance of the asphalt mixture. Furthermore, the use of the dynamically cross-linked water-damage-resistant asphalt modifier prepared by the present invention can reduce the use of SBS modifiers, significantly reducing the economic costs incurred during road construction.

[0036] (4) Under optimal conditions, the use of retired wind turbine blades as the main raw material effectively solves the serious resource waste and environmental pollution problems brought about by the wave of wind turbine blade retirement, and achieves the overall goal of large-scale resource utilization of retired wind turbine blades. It is a green and harmless retired wind turbine blade recycling solution that can be developed on a large scale and utilized at a high value, and has significant economic benefits and engineering value. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] FIG1 is a SEM image of waste wind turbine blade powder in Example 1 of the present invention magnified 500 times;

[0038] FIG2 is a SEM image of waste wind turbine blade powder in Example 1 of the present invention magnified 5000 times;

[0039] FIG3 is a SEM image of the silanized product of the coating in Example 1 of the present invention, magnified 500 times;

[0040] FIG4 is a SEM image of the silanization product of the coating in Example 1 of the present invention, magnified 5000 times. DETAILED DESCRIPTION

[0041] The following describes the specific embodiments of the present invention in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention and are not intended to limit the present invention.

[0042] The endpoints of the ranges and any values ​​disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered to be specifically disclosed herein.

[0043] The first aspect of the present invention provides a method for preparing a dynamic cross-linking-based water-damage resistant asphalt modifier, the method comprising the following steps:

[0044] (1) mixing a substance containing glass fiber reinforced plastic with a silane hydrolyzate and drying the mixture to obtain a silanized product;

[0045] (2) mechanically blending the silanized product with an elastomer, crushing, and sieving to obtain a coated silanized product;

[0046] (3) Mixing the coated silanized product with sulfur to obtain a dynamic cross-linking-based water-damage resistant asphalt modifier, wherein the silane hydrolyzate is a solution obtained by mixing a silane coupling agent, anhydrous ethanol and water.

[0047] In the method of the present invention, the source of the material containing fiberglass is not limited. Specifically, the material containing fiberglass can be retired wind turbine blades or pure fiberglass.

[0048] In the method described in the present invention, the content of glass fiber in the retired wind turbine blade is greater than 70 weight%, specifically, for example, it can be 75 weight%, 80 weight%, 85 weight%, 90 weight%, 95 weight% or 100 weight%.

[0049] In the method of the present invention, in step (1), the fiberglass-containing material is first pulverized and sieved to obtain a powder. In a preferred embodiment, the particle size of the fiberglass-containing material is ≤ 0.3 mm.

[0050] In the method of the present invention, the silane hydrolyzed solution is prepared by adding a silane coupling agent to a mixed solution of anhydrous ethanol and water, and allowing the solution to stand at room temperature to obtain the silane hydrolyzed solution. In a preferred embodiment, the silane coupling agent, water, and anhydrous ethanol are mixed and allowed to stand for 10-60 minutes, specifically, for example, 10 minutes, 20 minutes, 30 minutes, 40 minutes, 50 minutes, or 60 minutes.

[0051] In the method of the present invention, in a preferred embodiment, the mass ratio of the silane coupling agent, the water and the anhydrous ethanol is (14-19): (6-11): 100, specifically, for example, 14:6:100, 15:8:100, 17:9:100 or 19:11:100.

[0052] In the method of the present invention, in a preferred embodiment, the silane coupling agent is selected from one or more of KH550 (γ-aminopropyltriethoxysilane), KH560 (γ-(2,3-epoxypropyloxy)propyltrimethoxysilane), and KH570 (γ-methacryloxypropyltrimethoxysilane). In a more preferred embodiment, the silane coupling agent is KH550.

[0053] In the method of the present invention, in step (1), the mass ratio of the substance containing fiberglass to the silane coupling agent in the silane hydrolyzate is 100:(10-20), specifically, for example, it can be 100:10, 100:12, 100:14, 100:15, 100:17, 100:18, 100:19 or 100:20.

[0054] In the method of the present invention, in step (1), the mixing method is water bath stirring. In a preferred embodiment, the mixing conditions include: a temperature of 55-85°C, specifically, for example, 55°C, 60°C, 65°C, 70°C, 75°C, 80°C or 85°C, and a time of 10-60 minutes, specifically, for example, 10 minutes, 20 minutes, 30 minutes, 40 minutes, 50 minutes or 60 minutes.

[0055] In the method of the present invention, in step (1), the drying conditions include: a temperature of 80-140°C, specifically, for example, 80°C, 90°C, 100°C, 110°C, 120°C, 130°C or 140°C, and a time of 50-200 min, specifically, for example, 50 min, 100 min, 150 min or 200 min.

[0056] In the method described in the present invention, in step (2), the mass ratio of the silanization product to the elastomer is 100:(15-45), specifically, for example, it can be 5:1, 4:1, 10:3, 100:38, 100:40 or 100:45.

[0057] In the method of the present invention, in a preferred embodiment, the elastomer is selected from one or more of SBR (styrene-butadiene rubber), SBS (styrene-butadiene-styrene block copolymer), SIS (styrene-isoprene-styrene block copolymer), SE / BS (hydrogenated styrene-butadiene-styrene copolymer), IIR (butyl rubber), and EVA (ethylene-vinyl acetate copolymer). In a more preferred embodiment, the elastomer is SBR (styrene-butadiene rubber).

[0058] In the method described in the present invention, in step (2), the conditions for mechanical blending include: a temperature of 50-70°C, specifically, for example, 50°C, 55°C, 60°C, 65°C or 70°C; a blending speed of 40-70rpm, specifically, for example, 40rpm, 55rpm, 60rpm or 70rpm; and a time of 15-40min, specifically, for example, 15min, 20min, 25min, 30min or 40min.

[0059] In the method of the present invention, in step (2), the crushing is freeze crushing, specifically, the freeze crushing is carried out in a freeze crusher.

[0060] In the method of the present invention, in step (2), the particle size of the coated silanization product is ≤0.3 mm.

[0061] In the method of the present invention, the mass ratio of the elastomer to the sulfur is 100:(1.5-5), specifically, for example, it can be 100:1.5, 100:2, 100:3, 100:4 or 100:5.

[0062] In the method of the present invention, in step (3), the sulfur can be obtained commercially.

[0063] In the method of the present invention, in step (3), it is sufficient to uniformly mix the silanized product and sulfur.

[0064] The second aspect of the present invention provides a dynamic cross-linking-based water-damage resistant asphalt modifier prepared by the method described above.

[0065] The third aspect of the present invention provides a method for preparing modified asphalt, which comprises mixing the above-mentioned dynamically cross-linked water damage resistance asphalt modifier with an optional SBS modifier and a base asphalt. In this context, the base asphalt refers to a molten base asphalt.

[0066] In the method for preparing modified asphalt of the present invention, in a specific embodiment, when the above-mentioned dynamically cross-linked anti-water damage asphalt modifier and base asphalt are mixed, the weight ratio of the dynamically cross-linked anti-water damage asphalt modifier to the base asphalt is (1-20):100, specifically, for example, 1:100, 2:100, 3:100, 4:100, 5:100, 6:100, 10:100, 15:100 or 20:100. In a preferred embodiment, the weight ratio of the dynamically cross-linked anti-water damage asphalt modifier to the base asphalt is (4-6):100.

[0067] In the method for preparing the modified asphalt of the present invention, in a specific embodiment, when the above-mentioned dynamically cross-linked anti-water damage asphalt modifier, SBS modifier and base asphalt are mixed, the weight ratio of the total weight of the dynamically cross-linked anti-water damage asphalt modifier and the SBS modifier to the base asphalt is (1-20):100, specifically, for example, 1:100, 2:100, 3:100, 4:100, 5:100, 6:100, 10:100, 15:100 or 20:100. In a preferred embodiment, the weight of the dynamically cross-linked anti-water damage asphalt modifier accounts for 30-70% of the total weight of the dynamically cross-linked anti-water damage asphalt modifier and the SBS modifier, for example, 30%, 40%, 50%, 60% or 70%.

[0068] In the preparation method of the modified asphalt of the present invention, the mixing method is mechanical blending to ensure that the anti-water damage asphalt modifier is fully dispersed or dissolved and swelled in the base asphalt. In a preferred embodiment, the mechanical blending steps are:

[0069] (1) high-speed stirring by a high-speed shearing device, with a shear rate of 2500-4000 r / min, for example, 2500 r / min, 3000 r / min, 3500 r / min or 4000 r / min, a stirring time of 40-60 min, for example, 40 min, 50 min or 60 min, and a stirring temperature of 150-210° C., for example, 150° C., 160° C., 170° C., 175° C., 190° C., 200° C. or 210° C.;

[0070] (2) low-speed stirring is performed by a low-speed shearing device, the shear rate is 200-1500 r / min, for example, 200 r / min, 500 r / min, 800 r / min, 1000 r / min, 1200 r / min or 1500 r / min, the stirring time is 60-240 min, for example, 60 min, 120 min, 180 min or 240 min, and the stirring temperature is 150-210°C, for example, 150°C, 170°C, 175°C, 180°C, 185°C, 200°C or 210°C.

[0071] The fourth aspect of the present invention provides a modified asphalt prepared by the above-described method.

[0072] A fifth aspect of the present invention provides a method for preparing a modified asphalt mixture, comprising preheating the modified asphalt, aggregate and mineral powder described above, respectively, and then mixing the preheated modified asphalt, aggregate and mineral powder.

[0073] In the preparation method of the modified asphalt mixture of the present invention, the aggregate can be a conventional choice in the art.

[0074] In the method for preparing the modified asphalt mixture of the present invention, the mineral powder can be a conventional choice in the art.

[0075] In the method for preparing a modified asphalt mixture according to the present invention, in a preferred embodiment, the ratio of the weight of the modified asphalt to the total weight of the aggregate and the mineral powder is (4-6):100, specifically, for example, 4:100, 4.5:100, 5:100, 5.5:100, or 6:100. In a more preferred embodiment, the amount of the mineral powder used accounts for 4-6% by weight of the total weight of the aggregate and the mineral powder, for example, 4% by weight, 4.5% by weight, 5% by weight, 5.5% by weight, or 6% by weight.

[0076] In the preparation method of the modified asphalt mixture described in the present invention, in a specific embodiment, the preheating temperature of the aggregate and the mineral powder is 170-210°C, and the preheating time is 1-8 hours; the modified asphalt is preheated to a molten state at a temperature of 165-190°C.

[0077] In the method for preparing the modified asphalt mixture of the present invention, in a specific operation process, the preheated modified asphalt and mineral powder are sequentially added to the preheated aggregate for mixing, and the specific steps are as follows:

[0078] (1) the preheated aggregate is mixed at a temperature of 180-195° C. for 5-25 seconds;

[0079] (2) adding molten modified asphalt to the aggregate and continuing to mix for 10-60 seconds;

[0080] (3) Adding the preheated mineral powder to the mixture of the modified asphalt and aggregate and mixing for 60-300 seconds to obtain the modified asphalt mixture.

[0081] The sixth aspect of the present invention provides a modified asphalt mixture prepared by the method described above.

[0082] The following examples further illustrate the dynamic cross-linking water damage resistance asphalt modifier described herein, its preparation method, and its application. These examples are based on the technical solutions of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following examples.

[0083] The experimental methods in the following examples, unless otherwise specified, are all conventional methods in the art. The experimental materials used in the following examples, unless otherwise specified, are all commercially available.

[0084] In the following embodiments and comparative examples, retired wind turbine blades are from blades retired from a domestic wind farm; the matrix asphalt used is No. 70 matrix asphalt provided by a domestic company, the aggregate is limestone gravel provided by a domestic factory, and the mineral powder is limestone fine powder provided by a domestic factory.

[0085] Example 1

[0086] The retired wind turbine blades in this example were sourced from a wind farm. The glass fiber content in the retired wind turbine blades was 80% by weight. The retired wind turbine blades were pulverized and sieved to obtain waste wind turbine blade powder with a particle size of 0.3 mm or less. The microscopic morphology of the waste wind turbine blade powder is shown in Figures 1 and 2.

[0087] Silane hydrolyzate: Add 15 g of KH550 (γ-aminopropyltriethoxysilane) to a mixture of 100 g of anhydrous ethanol and 8 g of water, and let the mixture stand at room temperature for 20 min to obtain a silane hydrolyzate;

[0088] (1) Preparation of anti-water damage asphalt modifier based on dynamic cross-linking:

[0089] (1) 100 g of waste wind turbine blade powder was added to the silane hydrolyzate prepared in Example 1 and immersed in a 60° C. water bath, stirred for 20 min, and then dried in an oven at 105° C. for 120 min to obtain a silanized product;

[0090] (2) 100 g of the silanized product was uniformly mixed with 30 g of SBR (styrene-butadiene rubber), and then mechanically blended at a temperature of 55° C., a rotation speed of 50 rpm, and a time of 20 min. After the mixing was completed, the mixture was frozen, crushed, and sieved to obtain a coated silanized product with a particle size of ≤0.3 mm. The microscopic morphology of the coated silanized product is shown in Figures 3 and 4;

[0091] (3) 0.6 g of sulfur was mixed evenly with 100 g of the coated silanization product to obtain a dynamic cross-linking-based water-damage-resistant asphalt modifier.

[0092] (2) Application of anti-water damage asphalt modifier based on dynamic cross-linking:

[0093] Preparation of modified asphalt: 80 g of the dynamically cross-linked water-damage-resistant asphalt modifier prepared in Example 1 was added to 2000 g of molten base asphalt. The mixture was mechanically blended using a high-speed shear device at 170°C, a shear rate of 3000 r / min, and a stirring time of 60 min. The mixture was then transferred to a low-speed shear device and stirred at 170°C for 3 h at a shear rate of 500 r / min to prepare modified asphalt.

[0094] Preparation of modified asphalt mixture: The AC type dense gradation commonly used in highway pavement was selected, and a total of 20 kg of aggregate of corresponding size and mineral powder (wherein the mineral powder content was 5% by weight and the aggregate content was 95% by weight) were weighed and preheated in an oven at 180°C for 3 h. The modified asphalt prepared in Example 1 was preheated at 170°C to a molten state, and then the preheated aggregate was added to a stirring pot at 185°C and stirred for 10 seconds. Then, 0.8 kg of molten modified asphalt was added to the stirring pot and stirring was continued for 20 seconds. Finally, the preheated mineral powder was added and stirring was continued. After 90 seconds, the machine was stopped and the materials were discharged to prepare the modified asphalt mixture.

[0095] Example 2

[0096] The retired wind turbine blades in this embodiment are from a certain wind farm. The glass fiber content in the retired wind turbine blades is 75% by weight. The retired wind turbine blades are pulverized and sieved to obtain waste wind turbine blade powder with a particle size of ≤0.3 mm.

[0097] Silane hydrolyzate: Add 14 g of KH550 (γ-aminopropyltriethoxysilane) to a mixture of 100 g of anhydrous ethanol and 6 g of water, and let the mixture stand at room temperature for 30 min to obtain a silane hydrolyzate;

[0098] (1) Preparation of anti-water damage asphalt modifier based on dynamic cross-linking:

[0099] (1) 100 g of waste wind turbine blade powder was added to the silane hydrolyzate prepared in Example 2 and immersed in a 65°C water bath for 30 min, and then dried in an oven at 95°C for 150 min to obtain a silanized product;

[0100] (2) 100 g of the silanized product was mixed with 25 g of SBR (styrene-butadiene rubber) and then mechanically blended at a temperature of 60° C., a rotation speed of 50 rpm, and a time of 25 min. After the mixing was completed, the mixture was frozen, crushed, and sieved to obtain a coated silanized product with a particle size of ≤0.3 mm;

[0101] (3) 1 g of sulfur was mixed evenly with 100 g of the coated silanization product to obtain a dynamic cross-linking-based water-damage-resistant asphalt modifier.

[0102] (2) Application of anti-water damage asphalt modifier based on dynamic cross-linking:

[0103] Preparation of modified asphalt: 80 g of the dynamically cross-linked water-damage resistant asphalt modifier prepared in Example 2 was added to 2000 g of molten base asphalt, and mechanically blended using a high-speed shear device at 170° C., a shear rate of 3000 r / min, and a stirring time of 60 min. Subsequently, the mixed product was transferred to a low-speed shear device and stirred at 170° C. for 3 h at a shear rate of 500 r / min to prepare the modified asphalt.

[0104] Preparation of modified asphalt mixture: The AC type dense gradation commonly used in highway pavement was selected, and a total of 20 kg of aggregate of corresponding size and mineral powder (wherein the mineral powder content was 4% by weight and the aggregate content was 96% by weight) were weighed and preheated in an oven at 180°C for 3 h. The modified asphalt prepared in Example 2 was preheated at 170°C to a molten state, and then the preheated aggregate was added to a stirring pot at 185°C and stirred for 10 seconds. Then, 0.8 kg of molten modified asphalt was added to the stirring pot and stirring was continued for 20 seconds. Finally, the preheated mineral powder was added and stirring was continued. After 90 seconds, the machine was stopped and the materials were discharged to prepare the modified asphalt mixture.

[0105] Example 3

[0106] The retired wind turbine blades in this embodiment are from a certain wind farm. The glass fiber content in the retired wind turbine blades is 86% by weight. The retired wind turbine blades are pulverized and sieved to obtain waste wind turbine blade powder with a particle size of ≤0.3 mm.

[0107] Silane hydrolyzate: Add 14 g of KH550 (γ-aminopropyltriethoxysilane) to a mixture of 100 g of anhydrous ethanol and 6 g of water, and let the mixture stand at room temperature for 30 min to obtain a silane hydrolyzate;

[0108] (1) Preparation of anti-water damage asphalt modifier based on dynamic cross-linking:

[0109] (1) 100 g of waste wind turbine blade powder was added to the silane hydrolyzate prepared in Example 3 and immersed in the silane hydrolyzate, stirred in a 70°C water bath for 40 min, and then dried in an oven at 115°C for 100 min to obtain a silanized product;

[0110] (2) 100 g of the silanized product was mixed evenly with 30 g of SBR (styrene-butadiene rubber), and then mechanically blended at a temperature of 65° C., a rotation speed of 55 rpm, and a time of 25 min. After the mixing was completed, the mixture was frozen, crushed, and sieved to obtain a coated silanized product with a particle size of ≤0.3 mm;

[0111] (3) 0.6 g of sulfur was mixed evenly with 100 g of the coated silanization product to obtain a dynamic cross-linking-based water-damage-resistant asphalt modifier.

[0112] (2) Application of anti-water damage asphalt modifier based on dynamic cross-linking:

[0113] Preparation of modified asphalt: 80 g of the dynamically cross-linked water-damage-resistant asphalt modifier prepared in Example 3 was added to 2000 g of molten base asphalt, and mechanically blended using a high-speed shear device at 170° C., a shear rate of 3000 r / min, and a stirring time of 60 min. Subsequently, the mixed product was transferred to a low-speed shear device and stirred at 170° C. for 3 h at a shear rate of 500 r / min to prepare the modified asphalt.

[0114] Preparation of modified asphalt mixture: The AC type dense gradation commonly used in highway pavement was selected, and a total of 20 kg of aggregate of corresponding size and mineral powder (wherein the mineral powder content was 6% by weight and the aggregate content was 94% by weight) were weighed and preheated in an oven at 180°C for 3 h. The modified asphalt prepared in Example 3 was preheated at 170°C to a molten state, and then the preheated aggregate was added to a stirring pot at 185°C and stirred for 10 seconds. Then, 0.8 kg of molten modified asphalt was added to the stirring pot and stirring was continued for 20 seconds. Finally, the preheated mineral powder was added and stirring was continued. After 90 seconds, the machine was stopped and the materials were discharged to prepare the modified asphalt mixture.

[0115] Example 4

[0116] The retired wind turbine blades in this embodiment are from a certain wind farm. The glass fiber content in the retired wind turbine blades is 92% by weight. The retired wind turbine blades are pulverized and sieved to obtain waste wind turbine blade powder with a particle size of ≤0.3 mm.

[0117] Silane hydrolyzate: Add 17g KH550 (γ-aminopropyltriethoxysilane hydrolyzate) to a mixture of 100g anhydrous ethanol and 8g water, and let it stand at room temperature for 40min to obtain a silane aqueous solution;

[0118] (1) Preparation of anti-water damage asphalt modifier based on dynamic cross-linking:

[0119] (1) 100 g of waste wind turbine blade powder was added to the silane hydrolyzate prepared in Example 4 and immersed in the solution. The mixture was stirred in a 75°C water bath for 20 min and then dried in an oven at 125°C for 80 min to obtain a silanized product.

[0120] (2) 100 g of the silanized product was mixed evenly with 38 g of SBR (styrene-butadiene rubber), and then mechanically blended at a temperature of 50° C., a rotation speed of 60 rpm, and a time of 15 min. After the mixing was completed, the mixture was frozen, crushed, and sieved to obtain a coated silanized product with a particle size of ≤0.3 mm;

[0121] (3) 0.76 g of sulfur was mixed evenly with 100 g of the coated silanization product to obtain a dynamic cross-linking-based water-damage-resistant asphalt modifier.

[0122] (2) Application of anti-water damage asphalt modifier based on dynamic cross-linking:

[0123] Preparation of modified asphalt: 40 g of the dynamically cross-linked water-damage-resistant asphalt modifier prepared in Example 4 and 40 g of an SBS modifier were added to 2000 g of molten base asphalt, and mechanically blended using a high-speed shear device at 170° C., a shear rate of 3000 r / min, and a stirring time of 60 min. Subsequently, the mixed product was transferred to a low-speed shear device and stirred at 170° C. for 3 h at a shear rate of 500 r / min to prepare a modified asphalt.

[0124] Preparation of modified asphalt mixture: The AC type dense gradation commonly used in highway pavement was selected, and a total of 20 kg of aggregate of corresponding sizes and mineral powder (wherein the mineral powder content was 4.5% by weight and the aggregate content was 95.5% by weight) were weighed and preheated in an oven at 180°C for 3 h. The modified asphalt prepared in Example 4 was preheated at 170°C to a molten state, and then the preheated aggregate was added to a stirring pot at 185°C and stirred for 10 seconds. Then, 0.8 kg of molten modified asphalt was added to the stirring pot and stirring was continued for 20 seconds. Finally, the preheated mineral powder was added and stirring was continued. After 90 seconds, the machine was stopped and the materials were discharged to prepare the modified asphalt mixture.

[0125] Example 5

[0126] The retired wind turbine blades in this embodiment are from a certain wind farm. The glass fiber content in the retired wind turbine blades is 96% by weight. The retired wind turbine blades are pulverized and sieved to obtain waste wind turbine blade powder with a particle size of ≤0.3 mm.

[0127] Silane hydrolyzate: Add 19 g of KH550 (γ-aminopropyltriethoxysilane) to a mixture of 100 g of anhydrous ethanol and 11 g of water, and let the mixture stand at room temperature for 50 min to obtain a silane hydrolyzate.

[0128] (1) Preparation of anti-water damage asphalt modifier based on dynamic cross-linking:

[0129] (1) 100 g of waste wind turbine blade powder was added to the silane hydrolyzate prepared in Example 5 and immersed in the silane hydrolyzate, stirred in an 80°C water bath for 20 min, and then dried in an oven at 85°C for 180 min to obtain a silanized product;

[0130] (2) 100 g of the silanized product was mixed evenly with 40 g of SBR (styrene-butadiene rubber), and then mechanically blended at a temperature of 60° C., a speed of 60 rpm, and a time of 20 min. After the mixing was completed, the mixture was frozen, crushed, and sieved to obtain a coated silanized product with a particle size of ≤0.3 mm;

[0131] (3) 0.8 g of sulfur was mixed evenly with 100 g of the coated silanization product to obtain a dynamic cross-linking-based water-damage-resistant asphalt modifier.

[0132] (2) Application of anti-water damage asphalt modifier based on dynamic cross-linking:

[0133] Preparation of modified asphalt: 60 g of the dynamically cross-linked water-damage-resistant asphalt modifier prepared in Example 5 and 20 g of the SBS modifier were added to 2000 g of molten base asphalt, and mechanically blended using a high-speed shear device at 170° C., a shear rate of 3000 r / min, and a stirring time of 60 min. Subsequently, the mixed product was transferred to a low-speed shear device and stirred at 170° C. for 3 h at a shear rate of 500 r / min to prepare the modified asphalt.

[0134] Preparation of modified asphalt mixture: The AC type dense gradation commonly used in highway pavement was selected, and a total of 20 kg of aggregate of corresponding size and mineral powder (wherein the mineral powder content was 5.5 wt % and the aggregate content was 94.5 wt %) were weighed and preheated in an oven at 180°C for 3 h. The modified asphalt prepared in Example 5 was preheated at 170°C to a molten state, and then the preheated aggregate was added to a stirring pot at 185°C and stirred for 10 s. Then, 0.8 kg of molten modified asphalt was added to the stirring pot and stirring was continued for 20 s. Finally, the preheated mineral powder was added and stirring was continued. After 90 s, the machine was stopped and the materials were unloaded to prepare the modified asphalt mixture.

[0135] Example 6

[0136] The method of Example 1 was followed, except that when preparing the modified asphalt mixture, the asphalt-stone ratio was controlled to be 5%, that is, the molten modified asphalt was 1 kg, and the aggregate and mineral powder totaled 20 kg.

[0137] Example 7

[0138] The method of Example 1 was followed, except that when preparing the modified asphalt mixture, the oil-stone ratio was controlled to be 6%, that is, the amount of molten modified asphalt was 1.2 kg, and the total amount of aggregate and mineral powder was 20 kg.

[0139] Example 8

[0140] The method of Example 6 is followed, except that when preparing the modified asphalt, the modifier dosage is 5%, that is, 100g of the dynamic cross-linking anti-water damage asphalt modifier prepared in Example 1 is added to 2000g of the molten base asphalt.

[0141] Example 9

[0142] The method of Example 6 is followed, except that when preparing the modified asphalt, the modifier dosage is 6%, that is, 120g of the dynamic cross-linking anti-water damage asphalt modifier prepared in Example 1 is added to 2000g of the molten base asphalt.

[0143] Example 10

[0144] The method of Example 8 is followed, except that, when preparing the modified asphalt, the dynamic cross-linking-based water-damage resistance asphalt modifier prepared in Example 1 is compounded with the SBS modifier in amounts of 1.5% and 3.5%, respectively. That is, 30 g of the dynamic cross-linking-based water-damage resistance asphalt modifier and 70 g of the SBS modifier are added to 2000 g of the molten matrix asphalt.

[0145] Example 11

[0146] The method of Example 8 is followed, except that, when preparing the modified asphalt, the dynamic cross-linking-based water-damage resistance asphalt modifier prepared in Example 1 is compounded with the SBS modifier in amounts of 3.5% and 1.5%, respectively. That is, 70 g of the dynamic cross-linking-based water-damage resistance asphalt modifier and 30 g of the SBS modifier are added to 2000 g of the molten matrix asphalt.

[0147] Example 12

[0148] The method of Example 8 was followed, except that when preparing the dynamic cross-linking-based water-damage resistant asphalt modifier, the sulfur content pre-embedded in the modifier was 3% (relative to the mass of SBR), that is, 0.9 g of sulfur was mixed into 100 g of the silanization product and 30 g of SBR.

[0149] Example 13

[0150] The method of Example 8 was followed, except that when preparing the dynamic cross-linking-based water-damage resistant asphalt modifier, the sulfur content pre-embedded in the modifier was 4% (relative to the mass of SBR), that is, 1.2 g of sulfur was mixed into 100 g of the silanization product and 30 g of SBR.

[0151] Comparative Example 1

[0152] The method of Example 1 was followed, except that, when preparing the dynamic cross-linking-based water-damage resistance asphalt modifier, sulfur was replaced by dicumyl peroxide (DCP).

[0153] Test Case

[0154] Softening point: The modified asphalt in the examples and comparative examples was tested for softening point using the ring and ball method according to the test method of the "Testing Procedures for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E20-2011 T 0606). Specific testing procedures: (1) Place the sample ring containing the asphalt sample together with the sample base in a constant temperature water bath filled with water at 5°C ± 0.5°C for at least 15 minutes; (2) Pour freshly boiled water cooled to 5°C into a beaker, with the water level slightly below the depth mark on the vertical pole; (3) Place the sample ring containing the asphalt sample in step (1) into the circular hole of the middle plate of the bracket, put on the positioning ring, and place it in the beaker, and maintain the water temperature at 5°C ± 0.5°C. (4) Place the steel ball in the center of the sample in the middle of the positioning ring, immediately start the electromagnetic oscillator to make the water oscillate slightly, and start heating. Adjust the water temperature in the cup to maintain a rise of 5℃±0.5℃ per minute within 3 minutes; (5) The asphalt sample softens due to heat and gradually falls. When it contacts the surface of the lower bottom plate, read the temperature immediately.

[0155] Ductility: According to the test method of "Testing Procedures for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E20-2011 T 0605), the modified asphalt in the examples and comparative examples was tested for ductility at a test temperature of 10°C and a tensile speed of 5 cm / min±0.25 cm / min. Specific test process: (1) Prepare the ductility test specimen and place it in a ductility tester water tank at a water temperature of 10°C for at least 1.5 hours; (2) Place the specimen in the test area, remove the side mold and fix the mold end; (3) Start the test and perform constant temperature stretching, keep the equipment stable, and record the tensile length at break in cm;

[0156] Viscosity: According to the test method of "Testing Procedures for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E20-2011 T 0625), the ductility test of the modified asphalt in the examples and comparative examples was conducted at a test temperature of 135°C. Specific test process: (1) Place the asphalt sample in a viscosity test sample container and keep it warm for 1.5 hours; (2) Insert the selected rotor into the asphalt liquid level in the sample container to the specified height and continue to keep it warm for more than 15 minutes; (3) Start the viscosity test, observe the change in viscosity value, read and record the value after it stabilizes, and determine the average value of the three readings;

[0157] Marshall residual stability after immersion: According to the test method of "Test Procedure for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E20-2011 T 0702), the Marshall specimens of the modified asphalt mixtures of the embodiment and the comparative example were prepared by the compaction method. According to the test method of "Test Procedure for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E20-2011 T 0709), the Marshall stability tester was used to conduct a Marshall stability test on the above-mentioned asphalt mixture specimens. The difference between the Marshall test after immersion and the above-mentioned test is that the specimens need to be kept warm in a constant temperature water tank at 60°C for 48 hours. Furthermore, the percentage of the ratio of the Marshall stability after immersion to the Marshall stability before immersion is used as the Marshall residual stability after immersion, which is used to evaluate the water stability of the above-mentioned asphalt mixture. The larger the value, the better the water stability;

[0158] Dynamic stability: According to the test method of "Test Procedure for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E20-2011 T 0719), the asphalt mixture rutting specimens prepared in the examples and comparative examples were tested for high-temperature stability under the test conditions of a temperature of 60°C and a wheel pressure of 0.7 MPa. Dynamic stability was used as the main indicator to evaluate the high-temperature deformation resistance of the specimens.

[0159] Maximum flexural strain: According to the test method of "Test Procedure for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E20-2011 T 0715), the asphalt mixture specimens prepared in the examples and comparative examples were tested at a low temperature of -10°C and a loading rate of 50 mm / min. The low-temperature performance of the specimens was evaluated by the maximum flexural strain at specimen failure.

[0160] The softening point, ductility and viscosity of the modified asphalts and base asphalt prepared in Examples 1-13 and Comparative Example 1 were measured respectively. The results are shown in Table 1.

[0161] Table 1

[0162] As can be seen from Table 1, the dynamic cross-linking-based water-damage resistant asphalt modifier prepared by the present invention is used to prepare modified asphalt. In terms of softening temperature, the softening point of the prepared modified asphalt does not change much and is in a stable state; in terms of ductility, the synergistic effect of the elastomer (rubber) helps to compensate for the negative effect of waste wind turbine blade powder on the ductility of asphalt; in terms of viscosity, the synergistic effect of the elastomer (rubber) will not significantly increase the viscosity of the modified asphalt and affect the working performance.

[0163] The immersion Marshall residual stability, dynamic stability and maximum flexural strain of the modified asphalt mixtures prepared in Examples 1-13 and Comparative Example 1 were measured respectively, as well as the working performance and road performance standard requirements of the base asphalt mixture and the modified asphalt mixture in the field. The results are shown in Table 2.

[0164] Table 2

[0165] The data in Table 2 indicate that the asphalt modifier prepared by the present invention, through the combined use of a silane coupling agent, rubber treatment, and pre-embedded sulfur, is used to prepare modified asphalt, and modified asphalt mixtures prepared using this modified asphalt meet the road performance standards (≥85%) when measured for water stability, as assessed by residual Marshall stability after immersion. Furthermore, the rubber coating significantly improves the high-temperature performance of the asphalt mixture (dynamic stability). Furthermore, the maximum flexural strain meets the standard requirements for modified asphalt at low temperatures. Overall, the asphalt modifier prepared by the present invention has a good modification effect on asphalt mixtures, enabling the prepared asphalt mixtures to meet the road performance standards for modified asphalt mixtures, with particularly outstanding performance in terms of water stability.

[0166] The costs of the dynamic cross-linking-based water-damage resistant asphalt modifier prepared by the present invention and the SBS modifier are compared, and the results are shown in Table 3.

[0167] Table 3

[0168] As can be seen from Table 3, the technical solution of the dynamic cross-linking-based water-damage resistant asphalt modifier prepared by the present invention has significant economic benefits, can reduce the use of SBS modifier, and greatly reduce the economic costs incurred in road construction, thus having significant economic benefits and engineering value.

[0169] Furthermore, based on the above cost analysis, assuming a 1-kilometer, two-way, four-lane asphalt pavement (1000m long x 12m wide x 0.17m thick = 2040m³), based on typical engineering mix ratios, approximately 5140.8 tons of asphalt mixture and 11.75 tons of modifier are required. Therefore, using SBS modifier would cost approximately 185,700 yuan, while using the dynamically cross-linked water-damage-resistant asphalt modifier prepared by this invention would only cost approximately 44,900 yuan, saving 140,800 yuan.

[0170] In summary, the use of the dynamic cross-linking-based water-damage resistant asphalt modifier prepared by the present invention to prepare modified asphalt or modified asphalt mixture, and used for road construction, can save costs while having good working performance and road performance. At the same time, the present invention has a good prospect for high-value-added resource utilization of waste fiberglass materials.

[0171] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, various simple variations of the technical solution of the present invention may be made, including combining the various technical features in any other appropriate manner. These simple variations and combinations should also be regarded as disclosed in the present invention and fall within the scope of protection of the present invention.

Claims

1. A method for preparing a water-damage resistant asphalt modifier based on dynamic cross-linking, characterized in that: The method comprises the following steps: (1) mixing and drying the material containing fiberglass and silane hydrolyzate; (2) mechanically blending the product obtained in step (1) with an elastomer, crushing and sieving; (3) mixing the product obtained in step (2) with sulfur to obtain a water-damage resistant asphalt modifier based on dynamic cross-linking, The silane hydrolyzate is obtained by mixing a silane coupling agent, water and anhydrous ethanol.

2. The method according to claim 1, characterized in that The mass ratio of the elastomer to the sulfur is 100:(1.5-5).

3. The method according to claim 1, characterized in that In step (1), the mass ratio of the fiberglass-containing material to the silane coupling agent in the silane hydrolyzate is 100:(10-20).

4. The method according to claim 1, characterized in that: In step (2), the mass ratio of the product obtained in step (1) to the amount of the elastomer used is 100:(15-45).

5. The method according to claim 1 or 3, characterized in that: In step (1), the mixing conditions include: temperature of 55-85°C and time of 10-60 min.

6. The method according to claim 1 or 3, characterized in that: In step (1), the particle size of the fiberglass-containing material is ≤0.3 mm.

7. The method according to claim 1 or 4, characterized in that: In step (2), the mechanical blending conditions include: temperature of 50-70°C and time of 15-40 min; Preferably, in step (2), the elastomer is selected from one or more of styrene-butadiene rubber, styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, hydrogenated styrene-butadiene-styrene copolymer, butyl rubber and ethylene-vinyl acetate copolymer.

8. The method according to claim 1 or 4, characterized in that: In step (2), the crushing is freeze crushing; The particle size of the product obtained in step (2) is ≤0.3 mm.

9. The method according to claim 1, characterized in that: The mass ratio of the silane coupling agent, the water and the anhydrous ethanol is (14-19): (6-11): 100; Preferably, the silane coupling agent is selected from one or more of γ-aminopropyltriethoxysilane, γ-(2,3-epoxypropyloxy)propyltrimethoxysilane and γ-methacryloxypropyltrimethoxysilane.

10. A dynamic cross-linking anti-water damage asphalt modifier prepared by the method according to any one of claims 1 to 9.

11. A method for preparing modified asphalt, characterized in that: The dynamic cross-linking-based water damage resistance asphalt modifier described in claim 10 is mixed with an optional SBS modifier and a base asphalt.

12. The method according to claim 11, characterized in that The weight ratio of the dynamic cross-linking-based water-damage-resistant asphalt modifier to the base asphalt is (1-20):

100.

13. The method according to claim 11, characterized in that The weight ratio of the total weight of the dynamically cross-linked anti-water damage asphalt modifier and the SBS modifier to the base asphalt is (1-20):

100.

14. A modified asphalt prepared by the method according to any one of claims 11 to 13.

15. A method for preparing a modified asphalt mixture, characterized in that: The modified asphalt, aggregate and mineral powder described in claim 14 are preheated separately, and then the preheated modified asphalt, aggregate and mineral powder are mixed.

16. The method according to claim 15, characterized in that The ratio of the weight of the modified asphalt to the total weight of the aggregate and the mineral powder is (4-6):

100.

17. A modified asphalt mixture prepared by the method according to claim 15 or 16.

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