A sunlight-responsive high-strength self-repairing polyurethane material and preparation method thereof

Abstract

The present invention discloses a kind of sunlight response high-intensity self-repairing polyurethane material and preparation method thereof, belong to the technical field of self-repairing materials, by the polyurethane containing azothiazole structure and metal ion coordinated in a certain proportion to obtain, the polyurethane containing azothiazole structure is by diisocyanate, the glycol containing azothiazole structure, long-chain diol, aminophenylboronic acid in a certain proportion, in N, N-dimethylformamide, room temperature stirring reaction 5 h preparation. The present invention realizes the rapid sunlight response self-repair of polyurethane material by introducing photoactive azothiazole structure into polyurethane, forming reversible metal coordination bond by azothiazole structure and metal ion. The light response self-repairing polyurethane material prepared by the present invention has a self-repairing efficiency of 95.1% after sunlight irradiation for 2 h, has rapid light response self-repairing performance, and has broad application prospects in the fields of self-repairing coating, smart coating and anti-corrosion coating.

Description

Technical Field

[0001] The present invention relates to the technical field of self-repairing materials, and in particular to a sunlight-responsive high-strength self-repairing polyurethane material and a preparation method thereof. Background Art

[0002] During use, polymer materials inevitably suffer damage due to friction and collisions, which can reduce their performance and shorten their service life. Self-healing materials can undergo reversible breaking and formation of covalent or non-covalent bonds under the influence of stimuli such as heat, light, humidity, pH, and chemical reagents, thereby repairing damaged areas, improving the material's safety, and extending its service life. Photoresponsive self-healing materials, with their instantaneous switching, remote control, and precise positioning capabilities, are attracting increasing attention from researchers. However, reported photoresponsive self-healing materials generally suffer from low repair efficiency, low mechanical strength, the requirement for specific wavelengths of light, and high surface temperatures, which limit their application.

[0003] This invention introduces an azothiazole structure into polyurethane and adds appropriate metal ions to form metal coordination bonds with the azothiazole structure, thereby preparing a high-strength, self-healing polyurethane material that responds to sunlight. The reversible breaking and formation of metal coordination bonds under sunlight imparts the polyurethane material with excellent self-healing properties. Summary of the Invention

[0004] In order to solve the problems of low repair efficiency, requirement for specific wavelength light irradiation and low mechanical strength of existing light-responsive self-repairing materials, the present invention proposes a sunlight-responsive high-strength self-repairing polyurethane material and a preparation method thereof.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A sunlight-responsive high-strength self-healing polyurethane material and a preparation method thereof, characterized in that the polyurethane material is obtained by coordinating a polyurethane containing an azothiazole structure and a metal ion, the molar ratio of the azothiazole structure to the metal ion in the polyurethane containing an azothiazole structure is 1:0.15-0.5, and the polyurethane containing an azothiazole structure is obtained by reacting a diisocyanate, a diol containing an azothiazole structure, a long-chain diol, and aminophenylboronic acid in a molar ratio of 1:0.5-0.8:0.2-0.5:0.03-0.15. The general structural formula of the polyurethane is:

[0007]

[0008] In the formula, the value range of m is 1~6, and the value range of n is 3~40;

[0009] Wherein, R1 is one or more of the following structural formulas;

[0010]

[0011] Wherein, R2 is one or more of the following structural formulas;

[0012]

[0013] In the formula, the value range of x is 1~30;

[0014] Furthermore, the sunlight-responsive high-strength self-healing polyurethane material and its preparation method are characterized in that the metal ions are selected from one or more of ferric chloride, zinc chloride, copper chloride, ferric nitrate, zinc nitrate, copper nitrate, terbium trifluoromethanesulfonate, zinc trifluoromethanesulfonate, and europium trifluoromethanesulfonate;

[0015] Furthermore, the sunlight-responsive high-strength self-repairing polyurethane material and its preparation method are characterized in that the aminophenylboronic acid is one or more of 2-aminophenylboronic acid, 3-aminophenylboronic acid and 4-aminophenylboronic acid;

[0016] Furthermore, the aforementioned sunlight-responsive high-strength self-repairing polyurethane material and preparation method thereof are characterized in that the structural formula of the diol containing an azothiazole structure is as follows:

[0017]

[0018] In the formula, the value range of m is 1~6;

[0019] Furthermore, the aforementioned sunlight-responsive high-strength self-repairing polyurethane material and its preparation method are characterized by comprising the following steps:

[0020] S1. Preparation of azothiazole-containing diol: Add azothiazole-containing diphenol, chlorine-substituted alkyl alcohol, potassium carbonate, and potassium iodide in a molar ratio of 1:2.2:2.4:0.4 to a round-bottom flask, dissolve with N,N-dimethylformamide, and react with stirring at 80°C for 10 hours. After the reaction, extract, wash, and dry to obtain the azothiazole-containing diol.

[0021] S2. Preparation of a polyurethane containing an azothiazole structure: Under nitrogen, dissolve a diisocyanate, a diol containing an azothiazole structure, and a long-chain diol in N,N-dimethylformamide, add a catalyst (dibutyltin dilaurate), and react at room temperature for 3-4 hours. Add aminophenylboronic acid and continue the reaction for 1-2 hours to obtain a polyurethane containing an azothiazole structure. The molar ratio of diisocyanate, diol containing an azothiazole structure, long-chain diol, and aminophenylboronic acid is 1:0.5-0.8:0.2-0.5:0.03-0.15.

[0022] S3. Preparation of a high-strength, self-healing polyurethane material responsive to sunlight: Dissolve a polyurethane containing an azothiazole structure in tetrahydrofuran, then add a methanol solution of a metal salt and stir overnight at room temperature. The molar ratio of the azothiazole group to the metal ion in the polyurethane is 1:0.15-0.5. After the reaction is completed, the mixture is introduced into a mold, and the solvent is dried in an oven to obtain a high-strength, self-healing polyurethane material responsive to sunlight.

[0023] Compared with the prior art, the present invention is beneficial in that:

[0024] First, the present invention introduces an azothiazole structure into polyurethane. The metal coordination bonds formed by the azothiazole and metal ions reversibly break and regenerate under sunlight, endowing the polyurethane with excellent self-healing properties, achieving a self-healing efficiency of 95.1%. The self-healing material prepared by the present invention uses sunlight as a stimulus, resolving the problem of existing photoresponsive self-healing materials requiring specific wavelengths of light for self-healing, and simplifying the self-healing process.

[0025] Secondly, the present invention uses a difunctional diol containing an azothiazole structure as a functional monomer and aminophenylboronic acid as a cross-linking agent to prepare a cross-linked polyurethane containing an azothiazole structure on the main chain, which significantly improves the mechanical properties of the polyurethane, overcomes the problem of poor mechanical properties of existing photoresponsive self-healing materials, and realizes that the photoresponsive self-healing material has high mechanical properties while maintaining high repair efficiency.

[0026] Other advantages, objectives and features of the present invention will be reflected in part from the following description and will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is the H NMR spectrum of the diol containing azothiazole structure.

[0028] Figure 2 This is the infrared spectrum of diol containing azothiazole structure.

[0029] Figure 3 This is the infrared spectrum of polyurethane PMHA-1.

[0030] Figure 4 This is the UV-visible absorption spectrum of polyurethane PMHA-1.

[0031] Figure 5 This is the differential scanning calorimetry diagram of polyurethane PMHA-1.

[0032] Figure 6 This is the tensile curve of polyurethane PMHA-1 before and after visible light response repair.

[0033] Figure 7 This is the tensile curve of polyurethane PMHA-1 before and after sunlight response repair.

[0034] Figure 8 This is the infrared spectrum of polyurethane PMHA-2.

[0035] Figure 9 This is the differential scanning calorimetry diagram of polyurethane PMHA-2.

[0036] Figure 10 This is the tensile curve of polyurethane PMHA-2 before and after visible light response repair. DETAILED DESCRIPTION

[0037] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention and are not used to limit the present invention.

[0038] Example 1

[0039] (1) Preparation of diols containing azothiazole structure:

[0040] 3 g (10.66 mmol) of diphenol containing an azothiazole structure, 3.2 g (23.42 mmol) of chlorohexanol, 3.53 g (25.57 mmol) of potassium carbonate, and 0.71 g (4.27 mmol) of potassium iodide were added to a 100 mL single-necked flask and dissolved with N,N-dimethylformamide. The mixture was refluxed at 80°C for 10 hours at a speed of 350 r / min. The mixture was then extracted with ethyl acetate, washed three times with a 1 mol / L sodium hydroxide aqueous solution, washed three times with water, and washed three times with saturated brine. The organic layer was dried over anhydrous sodium sulfate for 2 hours and then spin-dried to obtain a diol containing an azothiazole structure. The reaction equation is as follows:

[0041]

[0042] Figure 1 This is the H NMR spectrum of diol containing azothiazole structure 1 H NMR (400 MHz, Chloroform-d) δ 8.05-7.99 (Ar-H), 7.29 (Ar-H), 7.09 (Ar-H), 7.04-7.00 (Ar-H), 4.07 (HO-CH), 3.71-3.63 (-OCH), 1.91-1.80 (-CH2), 1.68-1.42 (-CH2), confirming its successful preparation.

[0043] Figure 2The infrared spectrum of diol containing azothiazole structure, the infrared absorption peaks are 3282 cm -1 (-OH), 2936 cm -1 、2862 cm -1 (-CH2), 1593 cm -1 、1494 cm -1 、1465 cm -1 (Ar), 1388 cm -1 (CN), 1136cm -1 (COC), proving its successful preparation.

[0044] (2) Preparation of polyurethane containing azothiazole structure:

[0045] At room temperature, 1 g (2.5 mmol) of PEG400 (excluding water) was added to a 50 mL round-bottom flask, followed by 2 mL of a DMF solution containing 0.855 g (3.4 mmol) of MDI. After stirring at room temperature at 350 r / min for 5 min, DBTDL was added. The viscosity increased dramatically 20 min after the addition. 1 mL of DMF was added to wash the bottle, and 3 mL of DMF was added to dilute it again. After 10 min, 2 mL of a DMF solution of 0.3925 g (0.83 mmol) of a diol containing an azothiazole structure was added. After reacting for 4 h, 0.0228 g (0.16 mmol) of 2-aminophenylboronic acid was added and reacted for 1 h. After the reaction, it was poured into a mold to form a film.

[0046] (3) Preparation of high-strength self-healing polyurethane materials responsive to sunlight:

[0047] A polyurethane containing an azothiazole structure was dissolved in N,N-dimethylformamide, followed by the addition of a methanol solution of zinc trifluoromethanesulfonate and stirring overnight at room temperature. The molar ratio of the azothiazole groups to the zinc trifluoromethanesulfonate in the polyurethane was 1:0.5. After the reaction, the mixture was poured into a mold, and the solvent was dried in an oven to produce PMHA-1, a sunlight-responsive, high-strength, self-healing polyurethane material.

[0048] Figure 3 The infrared spectrum of polyurethane PMHA-1 is shown in Figure 1. The infrared absorption peaks are 3302 cm -1 (-NH-), 2924 cm -1 、2862 cm -1 (-CH2), 1723 cm -1 (-C=O), 1598 cm -1 、1535 cm -1 (Ar), 1310 cm -1(CN), 1136cm -1 (COC), proving the successful preparation of polyurethane PMHA-1.

[0049] Figure 4 The UV-visible absorption spectrum of the polyurethane PMHA-1 is shown below. The absorption peak of the trans azobenzothiazole structure is around 430 nm, while the absorption peak of the cis azobenzothiazole structure is around 550 nm. After irradiation with 450 nm blue light for 60 seconds, the trans structure converts to the cis structure, causing the peak at 430 nm to decrease and the peak at 550 nm to increase. Subsequently, after irradiation with 550 nm green light for 10 seconds, the cis structure converts to the trans structure, causing the peak at 430 nm to increase and the peak at 550 nm to decrease, demonstrating the visible light responsiveness of this polyurethane.

[0050] Figure 5 The differential scanning calorimetry (DSC) of polyurethane PMHA-1 shows that the glass transition temperature of PMHA-1 is 18.48°C.

[0051] Figure 6 The tensile curves of the polyurethane PMHA-1 before and after visible light-induced repair are shown. The figure shows that the initial tensile stress of the spline was 7.34 MPa and the elongation at break was 645%. After irradiation with 450nm visible light for 10 minutes and 550nm visible light for 10 minutes, the tensile stress of the repaired PMHA-1 reached 7.26 MPa and the elongation at break was 641%. The strength self-repair efficiency was 98.9%, and the strain self-repair efficiency was 99.3%.

[0052] Figure 7 The tensile strength curves of polyurethane PMHA-1 before and after solar-induced repair are shown. The initial tensile strength of the spline is 7.34 MPa, and the elongation at break is 645%. After 5 hours of solar-induced repair, the tensile stress is 6.94 MPa, and the elongation at break is 634%. The strength self-repair efficiency is 95.1%, and the strain self-repair efficiency is 98.2%.

[0053] Example 2

[0054] The method for preparing diol containing azothiazole structure is the same as step (1) in embodiment 1.

[0055] (2) Preparation of polyurethane containing azothiazole structure:

[0056] To a 50 mL round-bottom flask at room temperature, 0.4 g (1 mmol) of PEG400 (excluding water) was added, followed by 2 mL of a DMF solution containing 0.3878 g (1.55 mmol) of MDI. After stirring at room temperature at 350 r / min for 5 min, DBTDL was added. 20 min after the addition, the viscosity increased dramatically. 1 mL of DMF was added to wash the bottle, and 3 mL of DMF was added to dilute it. After 10 min, 2 mL of a DMF solution containing 0.2355 g (0.5 mmol) of azothiazole-containing diol was added. After reacting for 4 h, 0.0137 g (0.1 mmol) of 2-aminophenylboronic acid was added and reacted for 1 h. After the reaction, the mixture was poured into a mold to form a film.

[0057] (3) Preparation of high-strength self-healing polyurethane materials responsive to sunlight:

[0058] A polyurethane containing an azothiazole structure was dissolved in N,N-dimethylformamide, followed by the addition of a methanol solution of zinc trifluoromethanesulfonate and stirring overnight at room temperature. The molar ratio of the azothiazole groups to the zinc trifluoromethanesulfonate in the polyurethane was 1:0.5. After the reaction, the mixture was poured into a mold, and the solvent was dried in an oven to produce PMHA-2, a sunlight-responsive, high-strength, self-healing polyurethane material.

[0059] Figure 8 The infrared spectrum of PMHA-2, a high-strength self-healing polyurethane responsive to sunlight, has infrared absorption peaks at 3307 cm -1 (-NH-), 2920cm -1 、2854 cm -1 (-CH2), 1727cm -1 (-C=O), 1598 cm -1 、1535cm -1 (Ar), 1307 cm -1 (CN), 1136 cm -1 (COC), proving the successful preparation of polyurethane PMHA-1.

[0060] Figure 9 This is the differential scanning calorimetry diagram of polyurethane PMHA-2. It can be seen that the glass transition temperature of PMHA-1 is 36.17℃.

[0061] Figure 10This is the tensile curve of the sunlight-responsive high-strength self-healing polyurethane before and after light-responsive repair. It can be seen from the figure that the initial spline tensile stress is 3.08 MPa, and the elongation at break is 292%. After irradiation with 450 nm visible light for 40 minutes and 550 nm visible light for 40 minutes, the tensile strength of the repaired PMHA-2 is 2.76 MPa, and the elongation at break is 285%. Its strength self-repair efficiency is 89.6%, and its strain self-repair efficiency is 97.6%.

[0062] Example 3

[0063] The method for preparing diol containing azothiazole structure is the same as step (1) in embodiment 1.

[0064] (2) Preparation of polyurethane containing azothiazole structure:

[0065] At room temperature, 0.4 g (1 mmol) of PCL400 (excluding water) was added to a 50 mL round-bottom flask, followed by 2 mL of a DMF solution containing 0.5255 g (2.1 mmol) of MDI. After stirring at room temperature at 350 r / min for 5 min, DBTDL was added. The viscosity increased dramatically 20 min after the addition. 1 mL of DMF was added to wash the bottle, and 3 mL of DMF was added to dilute it again. After 10 min, 2 mL of a DMF solution of 0.471 g (1 mmol) of azothiazole-containing diol was added. After reacting for 4 h, 0.0273 g (0.2 mmol) of 3-aminophenylboronic acid was added and reacted for 1 h. After the reaction, it was poured into a mold to form a film.

[0066] (3) Preparation of high-strength self-healing polyurethane materials responsive to sunlight:

[0067] A polyurethane containing an azothiazole structure was dissolved in N,N-dimethylformamide, followed by the addition of a methanol solution of terbium trifluoromethanesulfonate and stirring overnight at room temperature. The molar ratio of the azothiazole groups to terbium trifluoromethanesulfonate in the polyurethane was 1:0.5. After the reaction, the mixture was poured into a mold, and the solvent was dried in an oven to produce a sunlight-responsive, high-strength, self-healing polyurethane material.

[0068] Example 4

[0069] The method for preparing diol containing azothiazole structure is the same as step (1) in embodiment 1.

[0070] (2) Preparation of polyurethane containing azothiazole structure:

[0071] At room temperature, 0.4 g (1 mmol) of PEG400 (excluding water) was added to a 50 mL round-bottom flask, followed by 2 mL of a DMF solution containing 0.3532 g (2.1 mmol) of HDI. After stirring at room temperature at 350 r / min for 5 min, DBTDL was added. The viscosity increased dramatically 20 min after addition. 1 mL of DMF was added to wash the bottle, and 3 mL of DMF was added to dilute it again. After 10 min, 2 mL of a DMF solution of 0.471 g (1 mmol) of a diol containing an azothiazole structure was added. After reacting for 4 h, 0.0273 g (0.2 mmol) of 4-aminophenylboronic acid was added and reacted for 1 h. After the reaction, it was poured into a mold to form a film.

[0072] (3) Preparation of high-strength self-healing polyurethane materials responsive to sunlight:

[0073] A polyurethane containing an azothiazole structure was dissolved in N,N-dimethylformamide, followed by the addition of a methanol solution of europium trifluoromethanesulfonate and stirring overnight at room temperature. The molar ratio of the azothiazole groups to the europium trifluoromethanesulfonate in the polyurethane was 1:0.5. After the reaction, the mixture was poured into a mold, and the solvent was dried in an oven to produce a sunlight-responsive, high-strength, self-healing polyurethane material.

[0074] Example 5

[0075] The method for preparing diol containing azothiazole structure is the same as step (1) in embodiment 1.

[0076] (2) Preparation of polyurethane containing azothiazole structure:

[0077] At room temperature, 0.4 g (1 mmol) of PEG400 (excluding water) was added to a 50 mL round-bottom flask, followed by 2 mL of a DMF solution containing 0.4668 g (2.1 mmol) of IPDI. After stirring at room temperature at 350 r / min for 5 min, DBTDL was added. The viscosity increased dramatically 20 min after addition. 1 mL of DMF was added to wash the bottle, and 3 mL of DMF was added to dilute it again. After 10 min, 2 mL of a DMF solution of 0.471 g (1 mmol) of a diol containing an azothiazole structure was added. After reacting for 4 h, 0.0273 g (0.2 mmol) of 3-aminophenylboronic acid was added and reacted for 1 h. After the reaction, it was poured into a mold to form a film.

[0078] (3) Preparation of high-strength self-healing polyurethane materials responsive to sunlight:

[0079] A polyurethane containing an azothiazole structure was dissolved in N,N-dimethylformamide, followed by the addition of a methanol solution of ferric nitrate and stirring overnight at room temperature. The molar ratio of the azothiazole groups to ferric nitrate in the polyurethane was 1:0.15. After the reaction, the mixture was poured into a mold, and the solvent was dried in an oven to produce a high-strength, self-healing polyurethane material that responds to sunlight.

[0080] Example 6

[0081] The method for preparing diol containing azothiazole structure is the same as step (1) in embodiment 1.

[0082] (2) Preparation of polyurethane containing azothiazole structure:

[0083] At room temperature, 0.4 g (1 mmol) of PEG400 (excluding water) was added to a 50 mL round-bottom flask, followed by 2 mL of a DMF solution containing 0.4668 g (2.1 mmol) of HDI. After stirring at room temperature at 350 r / min for 5 min, DBTDL was added. The viscosity increased dramatically 20 min after the addition. 1 mL of DMF was added to wash the bottle, and 3 mL of DMF was added to dilute it again. After 10 min, 2 mL of a DMF solution of 0.471 g (1 mmol) of azothiazole-containing diol was added. After reacting for 4 h, 0.0273 g (0.2 mmol) of 3-aminophenylboronic acid was added and reacted for 1 h. After the reaction was completed, it was poured into a mold to form a film.

[0084] (3) Preparation of high-strength self-healing polyurethane materials responsive to sunlight:

[0085] A polyurethane containing an azothiazole structure was dissolved in N,N-dimethylformamide, followed by the addition of a methanol solution of zinc trifluoromethanesulfonate and stirring overnight at room temperature. The molar ratio of the azothiazole groups to the zinc trifluoromethanesulfonate in the polyurethane was 1:0.5. After the reaction, the mixture was poured into a mold, and the solvent was dried in an oven to produce a sunlight-responsive, high-strength, self-healing polyurethane material.

[0086] Example 7

[0087] The method for preparing diol containing azothiazole structure is the same as step (1) in embodiment 1.

[0088] (2) Preparation of polyurethane containing azothiazole structure:

[0089] At room temperature, 1 g (2.5 mmol) of PEG400 (excluding water) was added to a 50 mL round-bottom flask, followed by 2 mL of a DMF solution containing 0.855 g (2.1 mmol) of MDI. After stirring at room temperature at 350 r / min for 5 min, DBTDL was added. The viscosity increased dramatically 20 min after addition. 1 mL of DMF was added to wash the bottle, and 3 mL of DMF was added to dilute it again. After 10 min, 2 mL of a DMF solution of 0.3925 g (0.83 mmol) of a diol containing an azothiazole structure was added. After reacting for 4 h, 0.0228 g (0.16 mmol) of 4-aminophenylboronic acid was added and reacted for 1 h. After the reaction, it was poured into a mold to form a film.

[0090] (3) Preparation of high-strength self-healing polyurethane materials responsive to sunlight:

[0091] A polyurethane containing an azothiazole structure was dissolved in N,N-dimethylformamide, then a methanol solution of zinc trifluoromethanesulfonate was added and stirred overnight at room temperature. The molar ratio of the azothiazole groups to the zinc trifluoromethanesulfonate in the polyurethane was 1:0.5. After the reaction, the mixture was poured into a mold, and the solvent was dried in an oven to produce a sunlight-responsive, high-strength, self-healing polyurethane material.

[0092] In summary, the present invention introduces a photoactive azobenzothiazole structure into polyurethane, and through a reversible metal coordination bond that responds to sunlight, achieves the solar-responsive self-repairing of high-strength polyurethane materials, solving the problem that existing photoresponsive self-repairing materials require irradiation with light of a specific wavelength.

[0093] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any technician familiar with the present profession can make some changes or modifications to equivalent embodiments of the present invention using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A sunlight-responsive high-strength self-repairing polyurethane material, characterized in that: The polyurethane material is obtained by coordinating a polyurethane containing an azothiazole structure with a metal ion. The molar ratio of the azothiazole structure to the metal ion in the polyurethane containing an azothiazole structure is 1:0.15-0.

5. The polyurethane containing an azothiazole structure is obtained by reacting a diisocyanate, a diol containing an azothiazole structure, a long-chain diol, and aminophenylboronic acid in a molar ratio of 1:0.5-0.8:0.2-0.5:0.03-0.

15. The general structural formula of the polyurethane is: ； In the formula, the value range of m is 1~6, and the value range of n is 3~40; Wherein, R1 is one or more of the following structural formulas; ； Wherein, R2 is one or more of the following structural formulas; ； Where, the value of x ranges from 1 to 30.

2. The sunlight-responsive high-strength self-repairing polyurethane material according to claim 1, characterized in that: The metal ion is selected from one or more of ferric chloride, zinc chloride, copper chloride, ferric nitrate, zinc nitrate, copper nitrate, terbium trifluoromethanesulfonate, zinc trifluoromethanesulfonate, and europium trifluoromethanesulfonate.

3. The sunlight-responsive high-strength self-repairing polyurethane material according to claim 1, characterized in that: The aminophenylboronic acid is one or more of 2-aminophenylboronic acid, 3-aminophenylboronic acid and 4-aminophenylboronic acid.

4. The sunlight-responsive high-strength self-repairing polyurethane material according to claim 1, characterized in that: The general structural formula of the diol containing azothiazole structure is as follows: ； Wherein, the value range of m is 1~6.

5. A method for preparing a sunlight-responsive high-strength self-repairing polyurethane material according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1. Preparation of diol containing an azothiazole structure: Add a diphenol containing an azothiazole structure, a chlorine-substituted alkyl alcohol, potassium carbonate, and potassium iodide in a molar ratio of 1:2.2:2.4:0.4 to a round-bottom flask, dissolve with N,N-dimethylformamide, and react with stirring at 80° C. for 10 hours. After the reaction, extract, wash, and dry to obtain the diol containing an azothiazole structure. S2. Preparation of a polyurethane containing an azothiazole structure: Under nitrogen protection, a diisocyanate, a diol containing an azothiazole structure, and a long-chain diol were dissolved in N,N-dimethylformamide, and then a catalyst, dibutyltin dilaurate, was added. The reaction was carried out at room temperature for 3-4 hours, and aminophenylboronic acid was added and the reaction was continued for 1-2 hours to obtain a polyurethane containing an azothiazole structure; the molar ratio of the diisocyanate, the diol containing an azothiazole structure, the long-chain diol, and the aminophenylboronic acid was 1:0.5-0.8:0.2-0.5:0.03-0.15; S3. Preparation of high-strength self-healing polyurethane material responsive to sunlight: dissolve the polyurethane containing azothiazole structure in tetrahydrofuran, then add a methanol solution of metal salt and stir overnight at room temperature; the molar ratio of azothiazole group to metal ion in the polyurethane is 1:0.15~0.5; after the reaction is completed, pour the mixture into a mold, dry the solvent in an oven to obtain a high-strength self-healing polyurethane material responsive to sunlight.

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