Preparation method of double-network toughening elastomer based on hydrogen bond and DA crosslinking

Abstract

The invention relates to the technical field of road maintenance, and discloses a preparation method of a double-network toughening elastomer based on hydrogen bond and DA crosslinking, and the preparation method comprises the following steps: S1, synthesizing a hydrogen bond monomer; s2, synthesizing a linear copolymer; and S3, synthesizing the hydrogen bond and DA cross-linked dual-network toughening elastomer. According to the technical scheme, the stability, toughness and creep resistance of the elastomer can be improved, and meanwhile the elastomer is endowed with the efficient self-repairing characteristic.

Description

Technical Field

[0001] The present invention relates to the technical field of road maintenance, and particularly relates to a preparation method of a double-network toughened elastomer based on hydrogen bonds and DA crosslinking. Background Art

[0002] With the continuous development of traffic infrastructure, the usage and load of road surfaces are increasing day by day. During long-term use, road surfaces are affected by natural environmental factors (such as temperature changes, rain erosion, ultraviolet radiation, etc.) and traffic loads, and will gradually develop diseases such as cracks, potholes, ruts, and looseness. If no measures are taken in time, these diseases will not only affect the flatness and driving comfort of the road surface, but also reduce the service life and safety of the road surface.

[0003] As a viscoelastic material, asphalt itself has a certain self-healing ability. Through the penetration and diffusion of asphalt on both sides of the crack, the crack can slowly heal automatically. However, this process is extremely slow, requiring not only a relatively high environmental temperature but also no traffic load. The operating asphalt pavement is in a complex natural environment and is affected by the cyclic action of high and low temperatures and traffic loads. Relying solely on the self-healing ability of asphalt cannot repair cracks automatically in time. Therefore, taking technical measures to greatly improve the self-healing ability of asphalt and asphalt mixtures and automatically repair cracks in time during the crack development process can greatly inhibit the crack development speed, reduce the crack depth and width, and improve the service level and service life of asphalt pavements.

[0004] Currently, the research on enhancing the self-healing behavior of asphalt concrete mainly adopts external repair technologies. The commonly used external repair technologies mainly include lime powder and microcapsule methods. Adding lime powder can improve the self-healing and performance of asphalt mixtures to some extent, but the effect is very small. Although the microcapsule method has a higher repair efficiency, it still has disadvantages such as only being able to repair once and the difficult control of capsule rupture conditions.

[0005] In view of this, researchers have focused on intrinsic self-repair technologies. The intrinsic self-repair technology is to construct an elastomer with a dynamic crosslinked network through molecular structure design, and then use this elastomer to prepare modified asphalt, thereby endowing the modified asphalt with the characteristics of high repair efficiency. However, the current single-network intrinsic self-repair elastomers have some inherent defects. Elastomers based on supramolecular interactions with a single-network structure (including hydrogen bond interactions, ionic bond interactions, metal ligand interactions, etc.) have disadvantages such as easy creep, low stability, and insufficient elasticity; while self-repair elastomers based on dynamic covalent bond interactions (such as DA reactions, disulfide bonds, carbon-nitrogen-oxygen bonds, etc.) lack an energy dissipation mechanism, so their toughness is poor. Summary of the Invention

[0006] The present invention aims to provide a preparation method of a double-network toughened elastomer based on hydrogen bonds and DA crosslinking to improve the stability, toughness and creep resistance of the elastomer, and at the same time endow it with efficient self-healing properties.

[0007] To achieve the above object, the present invention adopts the following technical solutions: A preparation method of a double-network toughened elastomer based on hydrogen bonds and DA crosslinking, comprising the following steps: S1, synthesize hydrogen bond monomers; S2, synthesize linear copolymers; S3, synthesize a double-network toughened elastomer with hydrogen bonds and DA crosslinking.

[0008] Preferably, the synthesis of hydrogen bond monomers in S1 comprises the following steps: S1.1, respectively measure a certain amount of hydroxyl-containing organic compounds and ester compounds, mix the two evenly, place them in an ice bath atmosphere, then add a catalyst and stir. React for 5-6 h, wherein the volume ratio of the hydroxyl-containing organic compounds, ester compounds and catalyst is 100: (100-180): (13.2-44) in sequence; S1.2, after the reaction is completed, wash the reaction product with a first organic solvent 3-4 times, then place the reaction product in a vacuum box and dry it to constant weight at 30°C - 60°C to obtain hydrogen bond monomers.

[0009] Preferably, the synthesis of linear copolymers in S2 comprises the following steps: S2.1, respectively weigh butyl acrylate, furfuryl methacrylate and the hydrogen bond monomers prepared in S1 according to a molar ratio of (70-95): (2-5): (8-15), place them in a three-necked flask equipped with a magnetic stirrer, then measure 40-200 mL of a second organic solvent and place it in the three-necked flask. Connect the three-necked flask with a spherical condenser, connect the condenser water for cooling, bubble for 20-30 min under an inert atmosphere, and then react at 70°C - 90°C for 6-7 h; S2.2, after the reaction is completed, put the reaction product into a non-polar solvent and precipitate it 3-4 times, then place the reaction product in a vacuum box and dry it to constant weight at 60°C - 90°C to obtain linear copolymers.

[0010] Preferably, the synthesis of the double-network toughened elastomer with hydrogen bonds and DA crosslinking in S3 comprises the following steps: S3.1, weigh a certain amount of the linear copolymers prepared in S2 and dissolve them in 100-300 ml of a third organic solvent; S3.2, Weigh a certain amount of the hydrogen-bonded monomer and bismaleimide prepared in S1 respectively, and dissolve them in 50 - 250 mL of the third organic solvent. The weight ratio of the linear copolymer prepared in S2 to the hydrogen-bonded monomer and bismaleimide prepared in S1 is 100:(40 - 90):(30 - 50); S3.3, Mix the solution in S3.1 with the solution in S3.2 evenly, pour the evenly mixed solution into a tetrafluoro mold, and react at 60°C - 70°C for 3 - 4 days. After the solvent evaporates, a double-network toughened elastomer crosslinked by hydrogen bonds and DA is prepared.

[0011] Preferably, the preparation method of the catalyst in S1.1 is: dissolve 2 mL of dibutyltin dilaurate in 20 mL of tetrahydrofuran solvent.

[0012] Preferably, in S1.1, the hydroxyl-containing organic compound is any one of p-methoxyphenol, p-hydroxybenzoate, N-(3-hydroxypropyl)acrylamide, N-hydroxy-3-(3-phenylaminosulfonylphenyl)acrylamide, N-hydroxymethylacrylamide, 4-hydroxydiphenyl ether, hydroquinone dihydroxyethyl ether, N-(2-hydroxyethyl)acrylamide.

[0013] Preferably, in S1.1, the ester compound is any one of n-butyl isocyanate, butyl acrylate, butyl methacrylate, furfuryl methacrylate, methyl 2-methylacrylate.

[0014] Preferably, the preparation method of the second organic solvent in S2.1 is: dissolve 3 - 10 g of azobisisobutyronitrile in 400 mL of ethyl acetate.

[0015] Preferably, the third organic solvent is any one of tetrahydrofuran, dimethylacetamide, and dimethylformamide.

[0016] Preferably, the inert atmosphere in S2.1 is any one of argon and nitrogen.

[0017] Compared with the prior art, the beneficial effects of this solution are: It has significant advantages in many aspects. On the one hand, it makes full use of the characteristic that the hydrogen-bond crosslinked network can effectively dissipate energy when it breaks under external force, significantly improving the toughness and mechanical strength of the elastomer. On the other hand, the high-strength DA bonds help the elastomer to quickly recover its shape after deformation, effectively ensuring the anti-creep performance and long-term stability. In addition, the hydrogen bonds and DA bonds can break and recombine at a specific temperature, thus endowing the ultra-thin wearing course asphalt binder with a powerful self-healing ability.

[0018] The preparation method of the double-network toughened elastomer based on hydrogen bonds and DA crosslinking provided by this technical solution can prepare an elastomer that can modify asphalt, improve the self-healing efficiency and comprehensive performance of asphalt, and provide an effective solution for improving the service level and service life of asphalt pavements. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a synthesis process diagram of the double-network toughened elastomer with hydrogen bonds and DA crosslinking of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] The following is a further detailed description through specific embodiments: Example 1 The preparation method of the double-network toughened elastomer based on hydrogen bonds and DA crosslinking includes the following steps: S1, synthesize hydrogen bond monomers; S1.1, measure a certain amount of hydroxyl-containing organic matter and ester compound respectively, and place them in an eggplant-shaped flask, stir until the two are evenly mixed, place the eggplant-shaped flask in an ice bath atmosphere, then add a catalyst to the eggplant-shaped flask and stir. React for 5-6 h. Among them, the volume ratio of the hydroxyl-containing organic matter, the ester compound and the catalyst is 100:(100-180):(13.2-44) in sequence. The hydroxyl-containing organic matter is any one of p-methoxyphenol, p-hydroxybenzoate, N-(3-hydroxypropyl)acrylamide, N-hydroxy-3-(3-phenylaminosulfonylphenyl)acrylamide, N-hydroxymethylacrylamide, 4-hydroxydiphenyl ether, hydroquinone dihydroxyethyl ether, N-(2-hydroxyethyl)acrylamide; the ester compound is any one of n-butyl isocyanate, butyl acrylate, butyl methacrylate, furfuryl methacrylate, methyl 2-methylacrylate; the preparation method of the catalyst is: dissolve 2 mL of dibutyltin dilaurate in 20 mL of tetrahydrofuran solvent; in this example, the hydroxyl-containing organic matter is selected as N-(2-hydroxyethyl)acrylamide, and its manufacturer is Shanghai Aladdin; the ester compound is selected as n-butyl isocyanate, and its manufacturer is Shanghai Macklin; the reaction time is 5 h, the dosage of the hydroxyl-containing organic matter is 100 mL, the dosage of the ester compound is 150 mL, and the dosage of the catalyst is 20 mL. It should be noted that the ice bath atmosphere refers to an ice-water mixture at 0 °C; S1.2 After the reaction is completed, wash the reaction product with a first organic solvent 3 to 4 times, and then place the reaction product in a vacuum box and dry it to constant weight at 30°C - 60°C to obtain a hydrogen-bonded monomer. Among them, the first organic solvent is any one of dimethylacetamide, n-hexane, diethyl ether, and tetrahydrofuran. In this example, the first organic solvent is selected as tetrahydrofuran solvent, the number of washing times is 3 times, and the drying temperature is 30°C. If the temperature is higher than 60°C, the generated hydrogen-bonded monomer is likely to degrade. If the temperature is lower than 30°C, the drying purpose cannot be achieved.

[0021] S2, Synthesize linear copolymer; S2.1 Weigh butyl acrylate, furfuryl methacrylate, and the hydrogen-bonded monomer prepared in S1 according to the molar ratio of (70 - 95):(2 - 5):(8 - 15) respectively, and place them in a three-necked flask equipped with a magnetic stirrer. Then measure 40 - 200 mL of a second organic solvent and place it in the three-necked flask. Connect the three-necked flask to a spherical condenser, connect the cooling water for cooling, and under an inert atmosphere, bubble for 20 - 30 min to remove the oxygen in the solution. Then react at 70°C - 90°C for 6 - 7 h. Among them, the preparation method of the second organic solvent is: dissolve 3 - 10 g of azobisisobutyronitrile in 400 mL of ethyl acetate, and the inert atmosphere is any one of argon and nitrogen; In this example, the amount of butyl acrylate used is 223 g, the amount of furfuryl methacrylate used is 10 g, and the amount of the carbamate prepared in S1 used is 42.9 g. That is, the molar ratio of butyl acrylate, furfuryl methacrylate, and the carbamate prepared in S1 is 87:3:10 in sequence. The preparation method of the second organic solvent is: dissolve 3 g of azobisisobutyronitrile in 400 mL of ethyl acetate, the amount of the second organic solvent used is 160 mL, the bubbling time is 20 min, the reaction temperature is 70°C, and the reaction time is 6 h. The manufacturer of butyl acrylate is Shanghai Aladdin, the manufacturer of furfuryl methacrylate is Shanghai Macklin, and the manufacturer of azobisisobutyronitrile is Shanghai Aladdin; S2.2 After the reaction is completed, put the reaction product into a non-polar solvent and precipitate it 3 to 4 times. Then place the reaction product in a vacuum box and dry it to constant weight at 60°C - 90°C to obtain a linear copolymer. Among them, the non-polar solvent is any one of petroleum ether and n-hexane. In this example, the number of precipitation times is 3 times, the drying temperature is 60°C, and the non-polar solvent is selected as petroleum ether; S3, Synthesize a double-network toughened elastomer crosslinked by hydrogen bonds and DA; S3.1 Weigh a certain amount of the linear copolymer prepared in S2 and dissolve it in 100 - 300 ml of a third organic solvent. Among them, the third organic solvent is any one of tetrahydrofuran, dimethylacetamide, and dimethylformamide. In this example, the third organic solvent is tetrahydrofuran, and the amount of the third organic solvent used is 130 mL; S3.2, Weigh a certain amount of the hydrogen bond monomer and bismaleimide prepared in S1 respectively, and dissolve them in 50 - 250 mL of the third organic solvent. The weight ratio of the linear copolymer prepared in S2 to the hydrogen bond monomer and bismaleimide prepared in S1 is 100:(40 - 90):(30 - 50). Among them, the third organic solvent is any one of tetrahydrofuran, dimethylacetamide, and dimethylformamide. In this example, the third organic solvent is tetrahydrofuran, and the dosage of the third organic solvent is 160 mL; the dosage of the linear copolymer prepared in S2 is 40 g, the hydrogen bond monomer prepared in S1 is 36 g, and the dosage of bismaleimide is 20 g, that is, the weight ratio of the linear copolymer prepared in S2 to the hydrogen bond monomer and bismaleimide prepared in S1 is 10:9:5; S3.3, Mix the solution in S3.1 and the solution in S3.2 evenly, and pour the evenly mixed solution into a square tetrafluoro mold. React at 60℃ - 70℃ for 3 - 4 days. After the solvent evaporates, a double - network toughened elastomer cross - linked by hydrogen bonds and DA is prepared. In this example, the reaction temperature is 60℃ and the reaction time is 3 days. Since the tetrafluoro mold has the advantages of a smooth surface and a small friction coefficient, using a tetrafluoro mold is beneficial for the demolding of the product, reduces the damage to the surface of the product, the material is not easily adhered to the surface of the mold, and is convenient for cleaning and repeated use.

[0022] The synthesis process of the double - network toughened elastomer cross - linked by hydrogen bonds and DA is as Figure 1 shown.

[0023] Detect the toughness, self - repair performance, stability, and anti - creep performance of the prepared double - network toughened elastomer based on hydrogen bonds and DA cross - linking. The detection results are shown in Table 2.

[0024] Examples 1 - 5 are based on the preparation raw materials and their dosages of the double - network toughened elastomer cross - linked by hydrogen bonds and DA shown in Table 1. At the same time, according to the preparation method of Example 1, a variety of different double - network toughened elastomers cross - linked by hydrogen bonds and DA are prepared.

[0025] The preparation raw materials and their dosages of the double - network toughened elastomer cross - linked by hydrogen bonds and DA in Examples 1 - 5 are shown in Table 1.

[0026] Table 1

[0027] The detection results of the toughness, stability, self - repair performance, and anti - creep performance of the double - network toughened elastomer cross - linked by hydrogen bonds and DA prepared in Examples 1 - 5 are shown in Table 2.

[0028] Table 2

[0029] Conclusion: The double-network toughened elastomer based on hydrogen bonding and DA crosslinking prepared by Examples 1-5 has good toughness, stability and creep resistance. Among them, the anti-fatigue life at 15 °C can reach up to 530,000 times at most, and the self-healing rate at 80-100 °C can reach up to 99% at most.

[0030] The above are only the embodiments of the present invention, and the specific technical solutions and / or common knowledge such as characteristics well known in the art are not described in detail herein. It should be noted that for those skilled in the art, without departing from the technical solution of the present invention, several deformations and improvements can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the implementation effect of the present invention and the practicability of the patent. The protection scope required by this application shall be subject to the content of its claims, and the specific implementation manners and the like recorded in the specification can be used to interpret the content of the claims.

Claims

1. Preparation method of double-network toughened elastomer based on hydrogen bond and DA crosslinking, characterized in that: It includes the following steps: S1, synthesize hydrogen bond monomers; S2, synthesize linear copolymers; S3, synthesize a double-network toughened elastomer crosslinked by hydrogen bonds and DA.

2. The preparation method of the double-network toughened elastomer based on hydrogen bond and DA crosslinking according to claim 1, wherein: The synthesis of hydrogen bond monomers in S1 includes the following steps: S1.1, respectively measure a certain amount of hydroxyl-containing organic compounds and ester compounds, mix the two evenly, place them in an ice bath atmosphere, then add a catalyst and stir. React for 5 - 6 h, where the volume ratio of the hydroxyl-containing organic compound, ester compound, and catalyst is 100:(100 - 180):(13.2 - 44); S1.2, after the reaction is completed, wash the reaction product with the first organic solvent 3 - 4 times, then place the reaction product in a vacuum box and dry it to constant weight at 30℃ - 60℃ to obtain hydrogen bond monomers.

3. The preparation method of the double-network toughened elastomer based on hydrogen bonds and DA crosslinking according to claim 2, wherein: The synthesis of linear copolymers in S2 includes the following steps: S2.1, respectively weigh butyl acrylate, furfuryl methacrylate, and the hydrogen bond monomers prepared in S1 according to a molar ratio of (70 - 95):(2 - 5):(8 - 15), place them in a three-necked flask equipped with a magnetic stirrer, then measure 40 - 200 mL of the second organic solvent and place it in the three-necked flask. Connect the three-necked flask to a spherical condenser, connect the cooling water for cooling, bubble for 20 - 30 min under an inert atmosphere, and then react at 70℃ - 90℃ for 6 - 7 h; S2.2, after the reaction is completed, put the reaction product into a non-polar solvent and precipitate it 3 - 4 times, then place the reaction product in a vacuum box and dry it to constant weight at 60℃ - 90℃ to obtain linear copolymers.

4. The preparation method of the double-network toughened elastomer based on hydrogen bonds and DA crosslinking according to claim 3, characterized in that: The synthesis of the double-network toughened elastomer crosslinked by hydrogen bonds and DA in S3 includes the following steps: S3.1, weigh a certain amount of the linear copolymer prepared in S2 and dissolve it in 100 - 300 ml of the third organic solvent; S3.2, respectively weigh a certain amount of the hydrogen bond monomers and bismaleimide prepared in S1 and dissolve them in 50 - 250 mL of the third organic solvent, and the weight ratio of the linear copolymer prepared in S2 to the hydrogen bond monomers and bismaleimide prepared in S1 is 100:(40 - 90):(30 - 50); S3.3, mix the solution in S3.1 and the solution in S3.2 evenly, pour the evenly mixed solution into a Teflon mold, and react at 60℃ - 70℃ for 3 - 4 days. After the solvent evaporates, obtain the double-network toughened elastomer crosslinked by hydrogen bonds and DA.

5. The preparation method of the double-network toughened elastomer based on hydrogen bond and DA crosslinking according to claim 4, characterized in that: The preparation method of the catalyst in S1.1 is: dissolve 2 mL of dibutyltin dilaurate in 20 mL of tetrahydrofuran solvent.

6. The preparation method of the double-network toughened elastomer based on hydrogen bonds and DA crosslinking according to claim 5, characterized in that: In S1.1, the hydroxyl-containing organic compound is any one of p-methoxyphenol, p-hydroxybenzoate, N-(3-hydroxypropyl)acrylamide, N-hydroxy-3-(3-phenylaminosulfonylphenyl)acrylamide, N-hydroxymethylacrylamide, 4-hydroxydiphenyl ether, hydroquinone dihydroxyethyl ether, N-(2-hydroxyethyl)acrylamide.

7. The preparation method of the dual-network toughened elastomer based on hydrogen bonds and DA crosslinking according to claim 6, characterized in that: In S1.1, the ester compound is any one of n-butyl isocyanate, butyl acrylate, butyl methacrylate, furfuryl methacrylate, methyl 2-methylacrylate.

8. The preparation method of the double-network toughened elastomer based on hydrogen bond and DA crosslinking according to claim 7, characterized in that: The preparation method of the second organic solvent in S2.1 is as follows: Dissolve 3-10 g of azobisisobutyronitrile in 400 mL of ethyl acetate.

9. The preparation method of the double-network toughened elastomer based on hydrogen bond and DA crosslinking according to claim 8, characterized in that: The third organic solvent is any one of tetrahydrofuran, dimethylacetamide, and dimethylformamide.

10. The preparation method of the double-network toughened elastomer based on hydrogen bond and DA crosslinking according to claim 9, characterized in that: The inert atmosphere in S2.1 is any one of argon and nitrogen.

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