Fiber web reinforced polyurethane fly ash composite material and preparation method thereof

Abstract

The invention discloses a fiber web reinforced polyurethane fly ash composite material and a preparation method thereof. The fiber web reinforced polyurethane fly ash composite material comprises the following components in parts by weight: 20-30 parts of diol fly ash and 100-120 parts of high-strength self-repairing polyurethane. According to the invention, the way of preparing the diol fly ash is provided, the diol fly ash reacts with an isocyanate group in polyurethane, so that the fly ash is well combined with the polyurethane, meanwhile, the double-bond acylhydrazone dihydric alcohol is introduced to prepare the high-strength self-repairing polyurethane, and the repairing performance of the composite material is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of polyurethanes, and specifically relates to a fiber mesh reinforced polyurethane fly ash composite material and a preparation method thereof. Background Art

[0002] With the continuous development of social economy, people's requirements for the use functions of existing bridges are increasing continuously. How to ensure the safety, durability and use functions of in-service bridges has become an urgent problem to be solved in the current engineering field. It is extremely urgent to reinforce the flexural strength of in-service dangerous and old bridges. When the flexural bearing capacity of a bridge cannot meet the requirements, the concrete cracks of the bridge will further expand, causing the corrosion and expansion of the steel bars in the beam, resulting in the exposure of the steel bars, greatly reducing the durability and safety of the bridge structure. At present, the existing reinforcement methods are mainly divided into two categories: direct reinforcement passive reinforcement and prestressed active reinforcement. The flexural reinforcement methods commonly used in actual engineering include: increasing the cross-section, externally bonding steel shapes, externally bonding fiber reinforced composite materials, external prestressed steel strands, prestressed steel ropes, modified polyurethane concrete method, etc. Among them, the modified polyurethane concrete method is a method of pouring lightweight, high-strength and high-toughness modified polyurethane concrete on the surface of the structure to be reinforced to improve the stiffness and bearing capacity of the main beam. Fly ash modified polyurethane concrete materials have high bond strength, flexural strength, toughness and frost resistance, can reduce the chloride ion permeability of repair mortar, and have good bond performance with ordinary cement concrete or steel.

[0003] The current existing technologies mainly have the following problems: poor combination of fly ash and polyurethane components, and poor repair performance. Summary of the Invention

[0004] In view of the above situation, in order to overcome the defects of the existing technologies, the present invention provides a fiber mesh reinforced polyurethane fly ash composite material and a preparation method thereof. In order to solve the problem of poor combination of fly ash and polyurethane components, the present invention proposes to prepare diol fly ash and react it with the isocyanate groups in polyurethane, realizing good combination of fly ash and polyurethane. At the same time, double bond acylhydrazone diol is introduced to prepare high-strength self-healing polyurethane, improving the repair performance of the composite material.

[0005] In order to achieve the above purpose, the technical solution adopted by the present invention is as follows: The present invention provides a fiber mesh reinforced polyurethane fly ash composite material and a preparation method thereof. The fiber mesh reinforced polyurethane fly ash composite material comprises the following components in parts by weight: 20-30 parts of diol fly ash, and 100-120 parts of high-strength self-healing polyurethane.

[0006] Preferably, the diol fly ash is prepared from the following components in parts by weight: 200-230 parts of fly ash, 1.5-2 parts of hexamethylene diisocyanate, 2.2-3 parts of γ-aminopropyltriethoxysilane, and 1-1.5 parts of aminobutanediol.

[0007] Preferably, the preparation method of the diol fly ash includes the following steps:

[0008] S1. Add hexamethylene diisocyanate into a reactor, fill with argon to remove air, drop γ-aminopropyltriethoxysilane into hexamethylene diisocyanate, and stir in a water bath to obtain an intermediate product;

[0009] S2. Add aminobutanediol into the intermediate product obtained in S1, and stir in an oil bath to obtain a modified coupling agent;

[0010] S3. Dry the fly ash, add it into a blender, heat to 130 °C, then add the modified coupling agent obtained in S2, stir under nitrogen protection, cool, separate, and dry to obtain diol fly ash.

[0011] Preferably, in S1, for the water bath stirring, the temperature is 80 - 90 °C, the speed is 160 - 180 rpm, and the time is 10 - 15 h.

[0012] Preferably, in S2, for the oil bath stirring, the temperature is 130 - 150 °C, the speed is 80 - 100 rpm, and the time is 8 - 10 h.

[0013] Preferably, in S3, for the heating and stirring, the temperature is 150 - 160 °C, the speed is 1300 - 1500 rpm, and the time is 60 - 80 min.

[0014] Preferably, the high-strength self-healing polyurethane is prepared from the following components in parts by weight: 13 - 16 parts of polytetrahydrofuran, 22 - 30 parts of diphenylmethane diisocyanate, 0.3 - 0.6 part of dibutyltin dilaurate, 2 - 3 parts of 3-allyl-4-hydroxybenzaldehyde, 2.5 - 3.5 parts of isophthalic dihydrazide, and 0.1 - 0.15 part of ammonium persulfate.

[0015] Preferably, the preparation method of the high-strength self-healing polyurethane includes the following steps:

[0016] (1) Add polytetrahydrofuran into a reactor, fill with argon to remove air, add diphenylmethane diisocyanate, and stir in a water bath to obtain a mixed solution;

[0017] (2) Add dibutyltin dilaurate into the mixture obtained in step (1), and stir in a water bath to obtain an oligomer;

[0018] (3) Add 3-allyl-4-hydroxybenzaldehyde into propanol at an addition amount of 0.5 - 0.6 g / mL to obtain solution 1, and add isophthalic dihydrazide into acetone at an addition amount of 0.25 - 0.35 g / mL to obtain solution 2;

[0019] (4) Mix solution 1 and solution 2 evenly, then stir at 200 - 300 rpm in a water bath at 70 °C for 60 - 80 min, filter, wash, and dry to obtain the double-bond acylhydrazone diol;

[0020] (5) Add the double-bond acylhydrazone diol to the oligomer, stir in a water bath, then add ammonium persulfate, and stir in a water bath to obtain the high-strength self-healing polyurethane.

[0021] The present invention also provides a preparation method of a fiber mesh-reinforced polyurethane fly ash composite material, which specifically includes the following steps:

[0022] Add the high-strength self-healing polyurethane and diol fly ash into the internal mixer in sequence, heat at 200 °C, stir at 80 rpm for 20 min, and cool to obtain the fiber mesh-reinforced polyurethane fly ash composite material.

[0023] The beneficial effects achieved by the present invention are as follows: The present invention uses hexamethylene diisocyanate and aminobutanediol to modify γ-aminopropyltriethoxysilane to obtain a coupling agent molecule with triethoxy and diol at both ends. By reacting with the hydroxyl groups on the surface of fly ash, diol fly ash is prepared, and by reacting with the isocyanate groups in polyurethane, good combination of fly ash and polyurethane is achieved, enhancing the tensile strength of the material; at the same time, 3-allyl-4-hydroxybenzaldehyde and isophthalic dihydrazide are used to prepare the double-bond acylhydrazone diol. The acylhydrazone bond introduced in polyurethane has good self-healing function, and at the same time, the double-bond polymerization enhances the cross-linking strength of polyurethane, enhancing the toughness and self-healing ability of polyurethane, and finally improving the repair performance of the composite material. Description of the Drawings

[0024] Figure 1 It is a result graph of the tensile strength of Examples 1 - 3 and Comparative Examples 1 - 2;

[0025] Figure 2 It is a result graph of the elongation at break of Examples 1 - 3 and Comparative Examples 1 - 2;

[0026] Figure 3 It is a result graph of the repair performance test of Examples 1 - 3 and Comparative Example 2;

[0027] Figure 4 It is a flow chart of preparing the modified coupling agent in Example 1 of the present invention.

[0028] The drawings are used to provide further understanding of the present invention, and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation to the present invention. Specific Embodiments

[0029] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0030] Unless otherwise defined, all professional and scientific terms used herein have the same meaning as those familiar to those skilled in the art. In addition, any methods and materials similar or equivalent to the described content can be applied to the present invention. The preferred implementation methods and materials described herein are for illustrative purposes only and do not limit the content of this application.

[0031] The experimental methods in the following embodiments are all conventional methods unless otherwise specified; the test materials used in the following embodiments are all obtained from commercial channels unless otherwise specified.

[0032] Example 1

[0033] A fiber web-reinforced polyurethane fly ash composite material comprises the following components in parts by weight: 20 parts of diol fly ash and 100 parts of high-strength self-healing polyurethane.

[0034] The diol fly ash is prepared from the following components in parts by weight: 200 parts of fly ash, 1.5 parts of hexamethylene diisocyanate, 2.2 parts of γ-aminopropyltriethoxysilane, and 1 part of aminobutylene glycol.

[0035] The high-strength self-healing polyurethane is prepared from the following components in parts by weight: 13 parts of polytetrahydrofuran, 22 parts of diphenylmethane diisocyanate, 0.3 part of dibutyltin dilaurate, 2 parts of 3-allyl-4-hydroxybenzaldehyde, 2.5 parts of isophthalic dihydrazide, and 0.1 part of ammonium persulfate.

[0036] The preparation method of the diol fly ash comprises the following steps:

[0037] S1. Add hexamethylene diisocyanate into a reactor, fill it with argon to remove air, drop γ-aminopropyltriethoxysilane into hexamethylene diisocyanate, stir at 80°C in a water bath at 160 rpm for 10 h to obtain an intermediate product;

[0038] S2. Add aminobutylene glycol into the intermediate product obtained in S1, stir at 130°C in an oil bath at 80 rpm for 8 h to obtain a modified coupling agent;

[0039] S3. Dry the fly ash, add it to a blender, heat it to 130°C, then add the modified coupling agent obtained in S2, heat it at 150°C under nitrogen protection and stir at 1300 rpm for 60 min, cool, separate, and dry to obtain the diol fly ash.

[0040] Preparation method of high-strength self-healing polyurethane, comprising the following steps:

[0041] (1) Add polytetrahydrofuran into a reactor, fill with argon to remove air, add diphenylmethane diisocyanate, and stir in a water bath to obtain a mixed solution;

[0042] (2) Add dibutyltin dilaurate into the mixture obtained in step (1), and stir in a water bath to obtain an oligomer;

[0043] (3) Add 3-allyl-4-hydroxybenzaldehyde into propanol at an addition amount of 0.5 g / mL to obtain solution 1, and add isophthalic dihydrazide into acetone at an addition amount of 0.25 g / mL to obtain solution 2;

[0044] (4) Mix solution 1 and solution 2 evenly, then stir at 200 rpm in a 70°C water bath for 60 min, filter, wash, and dry to obtain a double-bond acylhydrazone diol;

[0045] (5) Add the double-bond acylhydrazone diol into the oligomer, stir in a water bath, and then add ammonium persulfate, and stir in a water bath to obtain high-strength self-healing polyurethane.

[0046] The present invention also provides a preparation method of a fiber mesh-reinforced polyurethane fly ash composite material, specifically comprising the following steps:

[0047] Add the high-strength self-healing polyurethane and diol fly ash into a mixer in sequence, heat at 200°C and stir at 80 rpm for 20 min, and cool to obtain a fiber mesh-reinforced polyurethane fly ash composite material.

[0048] Example 2

[0049] A fiber mesh-reinforced polyurethane fly ash composite material comprises the following components in parts by weight: 30 parts of diol fly ash and 120 parts of high-strength self-healing polyurethane.

[0050] The diol fly ash is prepared from the following components in parts by weight: 230 parts of fly ash, 2 parts of hexamethylene diisocyanate, 3 parts of γ-aminopropyltriethoxysilane, and 1.5 parts of aminobutanediol.

[0051] The high-strength self-healing polyurethane is prepared from the following components in parts by weight: 16 parts of polytetrahydrofuran, 30 parts of diphenylmethane diisocyanate, 0.6 part of dibutyltin dilaurate, 3 parts of 3-allyl-4-hydroxybenzaldehyde, 3.5 parts of isophthalic dihydrazide, and 0.15 part of ammonium persulfate.

[0052] Preparation method of diol fly ash, comprising the following steps:

[0053] S1. Add hexamethylene diisocyanate into a reactor, fill with argon to remove air, and drop γ-aminopropyltriethoxysilane into hexamethylene diisocyanate. Stir at 180 rpm in a 90°C water bath for 15 h to obtain an intermediate product.

[0054] S2. Add aminobutanediol into the intermediate product obtained in S1. Stir at 100 rpm in a 150°C oil bath for 10 h to obtain a modified coupling agent.

[0055] S3. Dry fly ash, add it into a blender, heat to 130°C, then add the modified coupling agent obtained in S2. Stir at 1500 rpm in a 160°C heating under nitrogen protection for 80 min, cool, separate, and dry to obtain diol fly ash.

[0056] The preparation method of the high-strength self-healing polyurethane comprises the following steps:

[0057] (1) Add polytetrahydrofuran into a reactor, fill with argon to remove air, add diphenylmethane diisocyanate, and stir in a water bath to obtain a mixed solution.

[0058] (2) Add dibutyltin dilaurate into the mixture obtained in step (1), and stir in a water bath to obtain an oligomer.

[0059] (3) Add 3-allyl-4-hydroxybenzaldehyde into propanol at an addition amount of 0.6 g / mL to obtain solution 1, and add isophthalic dihydrazide into acetone at an addition amount of 0.35 g / mL to obtain solution 2.

[0060] (4) Mix solution 1 and solution 2 evenly, then stir at 300 rpm in a 70°C water bath for 80 min, filter, wash, and dry to obtain a double-bond acylhydrazone diol.

[0061] (5) Add the double-bond acylhydrazone diol into the oligomer, stir in a water bath, and then add ammonium persulfate, and stir in a water bath to obtain a high-strength self-healing polyurethane.

[0062] The present invention also provides a preparation method of a fiber mesh-reinforced polyurethane fly ash composite material, which specifically comprises the following steps:

[0063] Add the high-strength self-healing polyurethane and diol fly ash into a mixer in sequence, heat at 200°C, stir at 80 rpm for 20 min, and cool to obtain a fiber mesh-reinforced polyurethane fly ash composite material.

[0064] Example 3

[0065] A fiber mesh-reinforced polyurethane fly ash composite material comprises the following components in parts by weight: 25 parts of diol fly ash and 110 parts of high-strength self-healing polyurethane.

[0066] The diol fly ash is prepared from the following components in parts by weight: 220 parts of fly ash, 1.8 parts of hexamethylene diisocyanate, 2.5 parts of γ-aminopropyltriethoxysilane, and 1.3 parts of aminobutanediol.

[0067] The high-strength self-healing polyurethane is prepared from the following components in parts by weight: 15 parts of polytetrahydrofuran, 25 parts of diphenylmethane diisocyanate, 0.5 part of dibutyltin dilaurate, 2.5 parts of 3-allyl-4-hydroxybenzaldehyde, 3 parts of isophthalic dihydrazide, and 0.13 part of ammonium persulfate.

[0068] The preparation method of the diol fly ash comprises the following steps:

[0069] S1. Add hexamethylene diisocyanate into a reactor, fill it with argon to remove air, drop γ-aminopropyltriethoxysilane into hexamethylene diisocyanate, stir at 170 rpm in a water bath at 85 °C for 12 h to obtain an intermediate product;

[0070] S2. Add aminobutanediol into the intermediate product obtained in S1, stir at 90 rpm in an oil bath at 120 °C for 9 h to obtain a modified coupling agent;

[0071] S3. Dry the fly ash, add it into a blender, heat it to 130 °C, then add the modified coupling agent obtained in S2, under nitrogen protection, heat at 155 °C and stir at 1200 rpm for 70 min, cool, separate, and dry to obtain the diol fly ash.

[0072] The preparation method of the high-strength self-healing polyurethane comprises the following steps:

[0073] (1) Add polytetrahydrofuran into a reactor, fill it with argon to remove air, add diphenylmethane diisocyanate, and stir in a water bath to obtain a mixed solution;

[0074] (2) Add dibutyltin dilaurate into the mixture obtained in step (1), and stir in a water bath to obtain an oligomer;

[0075] (3) Add 3-allyl-4-hydroxybenzaldehyde into propanol at an addition amount of 0.55 g / mL to obtain solution 1, and add isophthalic dihydrazide into acetone at an addition amount of 0.3 g / mL to obtain solution 2;

[0076] (4) Mix solution 1 and solution 2 evenly, then stir at 250 rpm in a water bath at 70 °C for 70 min, filter, wash, and dry to obtain a double-bond acylhydrazide diol;

[0077] (5) Add the double-bond acylhydrazide diol into the oligomer, stir in a water bath, and then add ammonium persulfate, and stir in a water bath to obtain the high-strength self-healing polyurethane.

[0078] The present invention also provides a method for preparing a fiber mesh-reinforced polyurethane fly ash composite material, which specifically includes the following steps:

[0079] Add high-strength self-healing polyurethane and diol fly ash into a mixer in sequence, heat at 200 °C, stir at 80 rpm for 20 min, and then cool to obtain the fiber mesh-reinforced polyurethane fly ash composite material.

[0080] Comparative Example 1

[0081] This comparative example provides a composite material, which is different from Example 1 only in that the modified coupling agent is replaced by γ-aminopropyltriethoxysilane, and the other components and component contents are the same as those in Example 1.

[0082] Comparative Example 2

[0083] This comparative example provides a composite material, which is different from Example 1 only in that there is no double-bond acylhydrazone diol in the components, and the other components and component contents are the same as those in Example 1.

[0084] Experimental Example

[0085] 1. Mechanical property test

[0086] Use a TH-8203A tensile testing machine to conduct mechanical property tests on Examples 1-3 and Comparative Examples 1-2 in accordance with GB / T528-2009. Take 5 samples for each type, record the tensile strength and elongation at break each time, and take the average value as the tensile strength and elongation at break of the sample.

[0087] Figure 1 The result graph of the tensile strength of Examples 1-3 and Comparative Examples 1-2 is as shown in the figure. The tensile strengths of Examples 1-3 are 55.1 MPa, 55.5 MPa, and 55.3 MPa respectively, and the tensile strengths of Comparative Examples 1-2 are 30.2 MPa and 37.6 MPa respectively. The tensile strengths of Examples 1-3 are significantly higher than those of Comparative Example 1, indicating that the use of the modified coupling agent improves the tensile strength of the material. The tensile strengths of Examples 1-3 are significantly higher than those of Comparative Example 2, indicating that the use of double-bond acylhydrazone diol improves the tensile strength of the material.

[0088] Figure 2 The result graph of the elongation at break of Examples 1-3 and Comparative Examples 1-2 is as shown in the figure. The elongations at break of Examples 1-3 are 463.2%, 466.9%, and 463.5% respectively, and the elongations at break of Comparative Examples 1-2 are 332.3% and 264.6% respectively. The elongations at break of Examples 1-3 are significantly higher than those of Comparative Example 1, indicating that the use of the modified coupling agent improves the elongation at break of the material. The tensile strengths of Examples 1-3 are significantly higher than those of Comparative Example 2, indicating that the use of double-bond acylhydrazone diol improves the elongation at break of the material.

[0089] 2. Repair performance test

[0090] The materials obtained in Examples 1-3 and Comparative Example 2 were prepared into tensile splines. The tensile strength test was carried out using a Zwick / Roell / 005 type electronic universal material testing machine. The tensile rate was set at 200 mm / min. All samples were tested 5 times, and the average value of the tensile strength was taken and recorded as the initial tensile strength. Subsequently, the tensile splines were cut, acetic acid was dropped to increase the temperature for repair for 10 h, and then the above-mentioned tensile strength test was carried out again. At this time, the tensile strength was recorded as the tensile strength after repair. The repair rate calculation formula of the polyurethane is as follows:

[0091] Repair rate = tensile strength after repair / initial tensile strength × 100%.

[0092] Figure 3 FIG. is the result diagram of the repair performance test of Examples 1-3 and Comparative Example 2. As shown in the figure, the repair rates of Examples 1-3 and Comparative Example 2 are 89.2%, 89.3%, 89.6%, and 60.1% respectively. The repair rates of Examples 1-3 are significantly greater than those of Comparative Example 2, indicating that the use of double bond acylhydrazone diol improves the self-repair ability of the material.

[0093] Figure 4 FIG. is the flow chart for preparing the modified coupling agent in Example 1 of the present invention. As shown in the figure, the modified coupling agent is prepared from γ-aminopropyltriethoxysilane, hexamethylene diisocyanate, and aminobutanediol.

[0094] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirits of the present invention.

[0095] The above description of the present invention and its embodiments is not restrictive. What is shown in the drawings is only one of the embodiments of the present invention, and the actual application is not limited thereto. Generally speaking, if those of ordinary skill in the art are inspired by it and design similar ways and embodiments to this technical solution without creative efforts without departing from the purpose of the present invention, they should all fall within the protection scope of the present invention.

Claims

1. A fiber web-reinforced polyurethane fly ash composite material, characterized in that: The fiber web-reinforced polyurethane fly ash composite material comprises the following components in parts by weight: 20-30 parts of diol fly ash and 100-120 parts of high-strength self-healing polyurethane; The diol fly ash is prepared from the following components in parts by weight: 200-230 parts of fly ash, 1.5-2 parts of hexamethylene diisocyanate, 2.2-3 parts of γ-aminopropyltriethoxysilane, and 1-1.5 parts of aminobutanediol; The high-strength self-healing polyurethane is prepared from the following components in parts by weight: 13-16 parts of polytetrahydrofuran, 22-30 parts of diphenylmethane diisocyanate, 0.3-0.6 parts of dibutyltin dilaurate, 2-3 parts of 3-allyl-4-hydroxybenzaldehyde, 2.5-3.5 parts of isophthalic dihydrazide, and 0.1-0.15 parts of ammonium persulfate.

2. A preparation method of a web-reinforced polyurethane fly ash composite material according to claim 1, characterized in that: Specifically, it includes the following steps: Add the high-strength self-healing polyurethane and diol fly ash into a mixer in sequence, heat at 200°C, stir at 80 rpm for 20 min, and then cool to obtain the fiber web-reinforced polyurethane fly ash composite material.

3. The preparation method of the web-reinforced polyurethane fly ash composite material according to claim 2, characterized in that: The preparation method of the diol fly ash includes the following steps: S1. Add hexamethylene diisocyanate into a reactor, fill with argon to remove air, drop γ-aminopropyltriethoxysilane into hexamethylene diisocyanate, and stir in a water bath to obtain an intermediate product; S2. Add aminobutanediol into the intermediate product obtained in S1, and stir in an oil bath to obtain a modified coupling agent; S3. Dry the fly ash, add it into a mixer, heat to 130°C, then add the modified coupling agent obtained in S2, stir under nitrogen protection, cool, separate, and dry to obtain diol fly ash.

4. The preparation method of the web-reinforced polyurethane fly ash composite material according to claim 3, characterized in that: In S1, the water bath stirring is carried out at a temperature of 80-90°C, a speed of 160-180 rpm, and a time of 10-15 h.

5. The preparation method of the web-reinforced polyurethane fly ash composite material according to claim 4, characterized in that: In S2, the oil bath stirring is carried out at a temperature of 130-150°C, a speed of 80-100 rpm, and a time of 8-10 h.

6. The preparation method of the web-reinforced polyurethane fly ash composite material according to claim 5, characterized in that: In S3, the heating and stirring is carried out at a temperature of 150-160°C, a speed of 1300-1500 rpm, and a time of 60-80 min.

7. The preparation method of the web-reinforced polyurethane fly ash composite material according to claim 6, characterized in that: The preparation method of the high-strength self-healing polyurethane includes the following steps: (1) Add polytetrahydrofuran into a reactor, fill with argon to remove air, add diphenylmethane diisocyanate, and stir in a water bath to obtain a mixed solution; (2) Add dibutyltin dilaurate into the mixture obtained in step (1), and stir in a water bath to obtain an oligomer; (3) Add 3-allyl-4-hydroxybenzaldehyde into propanol at an addition amount of 0.5-0.6 g / mL to obtain solution 1, and add isophthalic dihydrazide into acetone at an addition amount of 0.25-0.35 g / mL to obtain solution 2; (4) Mix solution 1 and solution 2 evenly, then stir in a water bath at 70°C at 200-300 rpm for 60-80 min, filter, wash, and dry to obtain a double bond acylhydrazone diol; (5) Add the double bond acylhydrazone diol into the oligomer, stir in a water bath, and then add ammonium persulfate, and stir in a water bath to obtain high-strength self-healing polyurethane.

Images