An azobenzene boronic acid-based light-responsive multifunctional polyurethane material and a preparation method thereof

Abstract

This invention discloses a photoresponsive multifunctional polyurethane material based on azophenylboronic acid and its preparation method, belonging to the field of photoresponsive self-healing materials technology. The material is prepared by a monool-terminated polyurethane containing an azophenylboronic acid structure, specifically by reacting diisocyanate, long-chain diol, butanediol, trimethylolpropane, and the monool containing the azophenylboronic acid structure in N,N-dimethylformamide at 70°C for 3 h. This invention introduces the azophenylboronic acid structure into the polyurethane system and utilizes the photoinduced reversible isomerization effect of azophenyl to achieve precise control over the dynamic covalent bond breaking and recombination of boron-oxygen hexacyclic rings. This design endows the material with excellent photo-induced self-healing properties, achieving a self-healing efficiency of 96.9% under 365 nm and 450 nm light irradiation. Simultaneously, the material also exhibits photoresponsive color change and humidity-responsive deformation characteristics, showing broad application prospects in the field of smart polymers.

Description

Technical Field

[0001] This invention relates to the field of photoresponsive self-healing materials technology, and in particular to a photoresponsive multifunctional polyurethane material based on azophenylboronic acid and its preparation method. Background Technology

[0002] Polyurethane materials have established an irreplaceable position in many fields, including coatings, adhesives, elastomers, and smart responsive materials, due to their superior mechanical properties, excellent processability, and highly flexible chemical designability. However, these materials inevitably suffer mechanical damage during long-term use, leading to performance degradation and shortened lifespan. Therefore, endowing polyurethane materials with self-healing capabilities has become a key strategy for improving their durability and reliability. Among various self-healing systems, photoresponsive self-healing materials have attracted widespread attention from academia and industry due to their unique advantages such as instantaneous response, remote non-contact control, and precise positioning of damaged areas, enabling efficient and convenient repair processes. Nevertheless, currently reported photoresponsive self-healing materials are mainly based on azopyridine metal ion coordination bonds, which suffers from low strength and limited functionality, making it difficult to fully meet the increasingly complex practical application requirements. This provides ample room for in-depth research in related fields.

[0003] This invention utilizes a molecular design strategy to introduce azophenylboronic acid functional groups into the polyurethane backbone, successfully constructing a novel photoresponsive multifunctional polyurethane material. This material leverages the photoinduced reversible isomerization effect of azophenyl to achieve precise control over the dynamic covalent bond breaking and recombination of boron-oxygen hexacyclic rings, thereby endowing the material with excellent self-healing properties under light and multi-environmental responsiveness, significantly enhancing its intelligent response level. Summary of the Invention

[0004] To address the issues of low mechanical strength and limited functionality in existing photoresponsive self-healing materials, this invention proposes a photoresponsive multifunctional polyurethane material based on azophenylboronic acid and its preparation method.

[0005] To achieve the above objectives, the present invention employs the following technical solution: A photoresponsive multifunctional polyurethane material based on azophenylboronic acid and its preparation method are disclosed. The polyurethane material is obtained by reacting diisocyanate, long-chain diol, chain extender, and a monool containing an azophenylboronic acid structure in a molar ratio of 1:0.25~0.5:0.2~0.7:0.03~0.3. The general structural formula of the polyurethane is: ; In the formula, the value of n ranges from 3 to 40; In the formula, R1 is one or more of the following structural formulas; ; In the formula, R2 is one or more of the following structural formulas; ; In the formula, the value of x ranges from 4 to 30; In the formula, R3 is one or more of the following structural formulas; .

[0006] Furthermore, the aforementioned photoresponsive multifunctional polyurethane material based on azophenylboronic acid is characterized in that the monool containing the azophenylboronic acid structure has the following general structural formula: .

[0007] Furthermore, the aforementioned photoresponsive multifunctional polyurethane material based on azophenylboronic acid and its preparation method are characterized by comprising the following steps: S1. Preparation of monools containing azophenylboronic acid structure: Monophenols containing azophenylboronic acid structure, chlorohexanol, potassium carbonate, and potassium iodide were added to a round-bottom flask in a molar ratio of 1:1.1:2.4:0.4, dissolved in N,N-dimethylformamide, and stirred at 80°C for 10 hours. After the reaction was completed, the monools containing azophenylboronic acid structure were obtained by extraction, washing, and drying. S2. Preparation of photoresponsive multifunctional polyurethane material based on azophenylboronic acid: Under nitrogen protection, diisocyanate, long-chain glycol, and butanediol were dissolved in N,N-dimethylformamide, and then dibutyltin dilaurate catalyst was added. The reaction was carried out at 70°C for 1-2 hours. Then, trimethylolpropane was added, and stirring was continued for 30 min. Immediately afterwards, a monool containing an azophenylboronic acid structure was added, and the reaction was continued for 30 min to obtain a polyurethane containing an azophenylboronic acid structure. The molar ratio of diisocyanate, long-chain glycol, chain extender, and monool containing an azophenylboronic acid structure was 1:0.25~0.5:0.2~0.7:0.03~0.3. After the reaction was completed, the polyurethane solution containing the azophenylboronic acid structure was poured into a mold, and the solvent was dried in an oven to obtain a photoresponsive multifunctional polyurethane material based on azophenylboronic acid.

[0008] Compared with the prior art, the advantages of the present invention are: Firstly, this invention introduces an azophenylboronic acid structure into polyurethane, and through the photo-isomerization properties of azophenyl, achieves precise control over the dynamic covalent bonds of boron-oxygen hexacyclic rings, endowing the polyurethane material with excellent photoresponsive self-healing properties. At the same time, azophenylboronic acid can act as a crosslinking agent, significantly improving the mechanical properties of polyurethane, overcoming the problem of poor mechanical properties in existing photoresponsive self-healing materials, and realizing that photoresponsive self-healing materials can maintain high repair efficiency while having high mechanical properties, solving the pain point that existing materials cannot balance repair effect and structural strength.

[0009] Secondly, by introducing an azobenzeneboronic acid structure, this invention not only achieves photoresponsive self-healing but also endows polyurethane with multiple responsive functions, such as photoresponsive color change and humidity-responsive deformation. This solves the problem that existing photoresponsive self-healing materials have limited functionality and cannot meet the needs of complex application scenarios, significantly expanding their application scope and demonstrating broad application prospects.

[0010] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Attached Figure Description

[0011] Figure 1 The 1H NMR spectrum of a monool containing an azobenzeneboronic acid structure; Figure 2 The infrared spectrum of a monool containing an azophenylboronic acid structure; Figure 3 The infrared spectrum of polyurethane PDGA-1 is shown below. Figure 4 The image shows the UV-Vis absorption spectrum of polyurethane PDGA-1. Figure 5 Differential scanning calorimetry for polyurethane PDGA-1; Figure 6 The image shows the tensile curves of polyurethane PDGA-1 before and after photoresponse repair. Figure 7 Photochromic diagram of polyurethane PDGA-1; Figure 8 The humidity response diagram of polyurethane PDGA-1 is shown. Figure 9 The infrared spectrum of polyurethane PDGA-2; Figure 10 Differential scanning calorimetry for polyurethane PDGA-2;

[0012] Figure 11 The image shows the tensile curves of polyurethane PDGA-2 before and after photoresponse repair. Detailed Implementation

[0013] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0014] Example 1: (1) Preparation of monools containing azophenylboronic acid structure: 3 g of azophenylboronic acid-containing monophenol (11.71 mmol), 1.76 g of chlorohexanol (12.88 mmol), 3.88 g of potassium carbonate (28.12 mmol), and 0.78 g of potassium iodide (4.70 mmol) were added to a 100 mL single-necked flask and dissolved in 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 1 mol / L sodium hydroxide aqueous solution, three times with water, and three times with saturated brine. The organic layer was dried over anhydrous sodium sulfate for 2 hours and then evaporated to dryness to obtain the azophenylboronic acid-containing monophenol. The reaction equation is as follows: ; Figure 1 The 1H NMR spectrum of a monool containing an azophenylboronic acid structure 1 ¹H NMR (400 MHz, Methanol-D4) δ 8.08-7.97 (Ar-H), 7.94-7.57 (Ar-H), 7.45-7.28 (Ar-H), 7.14-7.02 (Ar-H), 6.98 (Ar-H), 4.11 (-OCH), 3.70-3.47 (HO-CH), 2.45 (-CH3), 2.02 (-CH2), 1.92-1.41 (-CH2), 1.41-1.17 (-CH2), confirming successful preparation.

[0015] Figure 2 The infrared spectrum of a monool containing an azophenylboronic acid structure is shown, with infrared absorption peaks at 3290 cm⁻¹. -1 (-OH), 2939 cm -1 2866 cm -1 (-CH2), 1587 cm -1 1485 cm -1 1404 cm -1 (Ar), 1343 cm -1 (CN), 1236 cm -1 (COC) proves that it was successfully prepared.

[0016] (2) Preparation of photoresponsive multifunctional polyurethane materials based on azophenylboronic acid: Add 1.5 g of dehydrated PEG1000 (1.5 mmol) to a 50 mL round-bottom flask at 70 °C. Then, add 2 mL of DMF solution, 1 mL of DMF solution containing 0.1757 g BDO (1.9 mmol), and 3 mL of DMF solution containing 0.6307 g HDI (3.7 mmol). Stir at 70 °C for 5 min at 350 r / min. Add DBTDL. After 20 min, the viscosity increases dramatically. Add 1 mL of wash bottle DMF, followed by another 2 mL of DMF for dilution. After 10 min, add 2 mL of DMF solution containing 0.1262 g HDI (0.75 mmol). After 30 min, add 3 mL of DMF for dilution, followed by 4 mL of DMF solution containing 0.0201 g TMP (0.15 mmol). After 30 min, add 2 mL of a solution containing 0.0534 g of azophenylboronic acid monool (0.15 mmol). The DMF solution was reacted for 30 min. After the reaction, the polyurethane solution containing the azophenylboronic acid structure was introduced into a mold, and the solvent was dried in an oven to obtain PDGA-1, a photoresponsive multifunctional polyurethane material based on azophenylboronic acid.

[0017] Figure 3 The image shows the infrared spectrum of the photoresponsive multifunctional polyurethane PDGA-1. The infrared absorption peaks are at 3320 cm⁻¹. -1 (-NH-), 2936 cm -1 2862 cm -1 (-CH2), 1687 cm -1 (C=O), 1534 cm -1 1465 cm -1 (Ar), 1347 cm -1 (BO), 1101 cm -1 (CO) confirms the successful preparation of polyurethane PDGA-1.

[0018] Figure 4 The image shows the UV-Vis absorption spectrum of the photoresponsive multifunctional polyurethane PDGA-1. Around 367 nm, the trans absorption peak of the azophenylboronic acid structure is observed, and around 470 nm, the cis absorption peak is observed. After 30 s of UV light exposure at 365 nm, the trans structure changes to the cis structure, resulting in a decrease in the peak at 367 nm and an increase in the peak at 470 nm. Subsequently, after 10 s of blue light exposure at 450 nm, the cis structure changes back to the trans structure, with the peak increasing at 367 nm and decreasing at 470 nm, demonstrating the visible light responsiveness of this polyurethane.

[0019] Figure 5This is a differential scanning calorimetry (DSC) curve of the photoresponsive multifunctional polyurethane PDGA-1. It can be seen that the melting temperature of the soft segment of PDGA-1 is 20.86℃.

[0020] Figure 6 The figures show the tensile curves of the photoresponsive multifunctional polyurethane PDGA-1 before and after photoresponsive repair. As can be seen from the figures, the initial tensile stress of the sample was 10.93 MPa, and the elongation at break was 1041.40%. After irradiation with a 365 nm light source for 10 min and then with a 450 nm light source for 10 min, the tensile stress of the repaired PDGA-1 was 11.75 MPa, and the elongation at break was 849.14%. Its strength self-healing efficiency was 107.5%, and its strain self-healing efficiency was 81.5%.

[0021] Figure 7 The image shows the photochromic properties of the photoresponsive multifunctional polyurethane PDGA-1. As can be seen, after 30 minutes of continuous irradiation with a 365 nm UV light source, the azophenylboronic acid structure of PDGA-1 changes from the trans to the cis configuration, resulting in a significant photochromic phenomenon. Subsequently, after 30 minutes of continuous irradiation with a 450 nm visible light source, the cis configuration changes back to the trans configuration, and the color is completely restored, achieving reversible photochromism. After multiple light cycle tests, PDGA-1 still maintains excellent reversible photochromic performance with no obvious signs of performance degradation.

[0022] Figure 8 The figure shows the humidity response of the photoresponsive multifunctional polyurethane PDGA-1. As can be seen, when PDGA-1 is stimulated by deionized water, it bends towards the side away from the water, reaching a maximum bending angle of 160.2° at 60 seconds. After drying and dehumidifying the PDGA-1, the bending deformation reversibly recovers, fully restoring its initial shape after 240 seconds, indicating that PDGA-1 has excellent humidity response performance.

[0023] Example 2: The method for preparing monools containing azophenylboronic acid structures is the same as step (1) in Example 1. (2) Preparation of photoresponsive multifunctional polyurethane materials based on azophenylboronic acid: Add 1.5 g of dehydrated PEG1000 (1.5 mmol) to a 50 mL round-bottom flask at 70 °C. Then, add 2 mL of DMF solution, 1 mL of DMF solution containing 0.1081 g BDO (1.2 mmol), and 3 mL of DMF solution containing 0.5046 g HDI (3.0 mmol). Stir at 70 °C for 5 min at 350 r / min. Add DBTDL. After 20 min, the viscosity increases dramatically. Add 1 mL of wash bottle DMF, followed by another 2 mL of DMF for dilution. After 10 min, add 2 mL of DMF solution containing 0.1262 g HDI (0.75 mmol). After 30 min, add 3 mL of DMF for dilution, followed by 4 mL of DMF solution containing 0.0201 g TMP (0.15 mmol). After 30 min, add 2 mL of a solution containing 0.0534 g of azophenylboronic acid monool (0.15 mmol). The DMF solution was reacted for 30 min. After the reaction, the polyurethane solution containing the azophenylboronic acid structure was introduced into a mold, and the solvent was dried in an oven to obtain the photoresponsive multifunctional polyurethane material PDGA-2 based on azophenylboronic acid.

[0024] Figure 9 The infrared spectrum of photoresponsive multifunctional polyurethane PDGA-2 is shown below. The infrared absorption peaks are at 3318 cm⁻¹. -1 (NH), 2934 cm -1 2857 cm -1 (-CH2), 1690 cm -1 (C=O), 1540 cm -1 1467 cm -1 (Ar), 1347cm -1 (BO), 1101 cm -1 (CO) confirms the successful preparation of polyurethane PDGA-2.

[0025] Figure 10 This is a differential scanning calorimetry (DSC) curve of the photoresponsive multifunctional polyurethane PDGA-2. It can be seen that the melting temperature of the soft segment of PDGA-2 is 28.18℃.

[0026] Figure 11The figure shows the tensile curves of the photoresponsive multifunctional polyurethane before and after photoresponsive repair. As can be seen from the figure, the initial tensile stress of the sample is 7.34 MPa and the elongation at break is 1333.2%. After being irradiated with a 365 nm light source for 10 min and a 450 nm light source for 5 min, the tensile strength of the repaired PDGA-2 is 7.11 MPa and the elongation at break is 1437.4%. Its strength self-repair efficiency is 96.9% and its strain self-repair efficiency is 107.8%.

[0027] Example 3: The method for preparing monools containing azophenylboronic acid structures is the same as step (1) in Example 1. (2) Preparation of photoresponsive multifunctional polyurethane materials based on azophenylboronic acid: Add 1.5 g of PTMG1000 (1.5 mmol) (dehydrated) to a 50 mL round-bottom flask at 70 °C. Then, add 2 mL of DMF solution, 1 mL of DMF solution containing 0.1081 g BDO (1.2 mmol), and 3 mL of DMF solution containing 0.5046 g HDI (3.0 mmol). Stir at 70 °C for 5 min at 350 r / min. Add DBTDL. After 20 min, the viscosity increases dramatically. Add 1 mL of wash bottle DMF, followed by another 2 mL of DMF for dilution. After 10 min, add 2 mL of DMF solution containing 0.1262 g HDI (0.75 mmol). After 30 min, add 3 mL of DMF for dilution, followed by 4 mL of DMF solution containing 0.0201 g TMP (0.15 mmol). After 30 min, add 2 mL of a solution containing 0.0534 g of azophenylboronic acid monool (0.15 mmol). The DMF solution was reacted for 30 minutes. After the reaction, the polyurethane solution containing the azophenylboronic acid structure was introduced into a mold, and the solvent was dried in an oven to obtain a photoresponsive multifunctional polyurethane material based on azophenylboronic acid.

[0028] Example 4: The method for preparing monools containing azophenylboronic acid structures is the same as step (1) in Example 1. (2) Preparation of photoresponsive multifunctional polyurethane materials based on azophenylboronic acid: Add 1.5 g of dehydrated PTMG1000 (1.5 mmol) to a 50 mL round-bottom flask at 70 °C. Then add 2 mL of DMF solution, 1 mL of DMF solution containing 0.1081 g BDO (1.2 mmol), and 3 mL of DMF solution containing 0.6670 g IPDI (3.0 mmol). Stir at 70 °C for 5 min at 350 r / min. Add DBTDL. After 20 min, the viscosity increases dramatically. Add 1 mL of wash bottle DMF, followed by another 2 mL of DMF for dilution. After 10 min, add 2 mL of DMF solution containing 0.1667 g HDI (0.75 mmol). After 30 min, add 3 mL of DMF for dilution, followed by 4 mL of DMF solution containing 0.0201 g TMP (0.15 mmol). After 30 min, add 2 mL of a solution containing 0.0534 g of azophenylboronic acid monool (0.15 mmol). The DMF solution was reacted for 30 minutes. After the reaction, the polyurethane solution containing the azophenylboronic acid structure was introduced into a mold, and the solvent was dried in an oven to obtain a photoresponsive multifunctional polyurethane material based on azophenylboronic acid.

[0029] Example 5: The method for preparing monools containing azophenylboronic acid structures is the same as step (1) in Example 1. (2) Preparation of photoresponsive multifunctional polyurethane materials based on azophenylboronic acid: Add 1.5 g of dehydrated PEG1000 (1.5 mmol) to a 50 mL round-bottom flask at 70 °C. Then add 2 mL of DMF solution, 1 mL of DMF solution containing 0.1081 g BDO (1.2 mmol), and 3 mL of DMF solution containing 0.6670 g IPDI (3.0 mmol). Stir at 70 °C for 5 min at 350 r / min. Add DBTDL. After 20 min, the viscosity increases dramatically. Add 1 mL of wash bottle DMF, followed by another 2 mL of DMF for dilution. After 10 min, add 2 mL of DMF solution containing 0.1667 g IPDI (0.75 mmol). After 30 min, add 3 mL of DMF for dilution, followed by 4 mL of DMF solution containing 0.0201 g TMP (0.15 mmol). After 30 min, add 2 mL of a solution containing 0.0534 g of azophenylboronic acid monool (0.15 mmol). The DMF solution was reacted for 30 minutes. After the reaction, the polyurethane solution containing the azophenylboronic acid structure was introduced into a mold, and the solvent was dried in an oven to obtain a photoresponsive multifunctional polyurethane material based on azophenylboronic acid.

[0030] Example 6: The method for preparing monools containing azophenylboronic acid structures is the same as step (1) in Example 1. (2) Preparation of photoresponsive multifunctional polyurethane materials based on azophenylboronic acid: Add 1.5 g of dehydrated PEG1000 (1.5 mmol) to a 50 mL round-bottom flask at 70 °C. Then add 2 mL of DMF solution, 1 mL of DMF solution containing 0.1081 g BDO (1.2 mmol), and 3 mL of DMF solution containing 0.7871 g MDI (3.0 mmol). Stir at 70 °C for 5 min at 350 r / min. Add DBTDL. After 20 min, the viscosity increases dramatically. Add 1 mL of wash bottle DMF, followed by another 2 mL of DMF for dilution. After 10 min, add 2 mL of DMF solution containing 0.1968 g MDI (0.75 mmol). After 30 min, add 3 mL of DMF for dilution, followed by 4 mL of DMF solution containing 0.0201 g TMP (0.15 mmol). After 30 min, add 2 mL of a solution containing 0.0534 g of azophenylboronic acid monool (0.15 mmol). The DMF solution was reacted for 30 minutes. After the reaction, the polyurethane solution containing the azophenylboronic acid structure was introduced into a mold, and the solvent was dried in an oven to obtain a photoresponsive multifunctional polyurethane material based on azophenylboronic acid.

[0031] Example 7: The method for preparing monools containing azophenylboronic acid structures is the same as step (1) in Example 1. (2) Preparation of photoresponsive multifunctional polyurethane materials based on azophenylboronic acid: Add 1.5 g of dehydrated PTMG1000 (1.5 mmol) to a 50 mL round-bottom flask at 70 °C. Then add 2 mL of DMF solution, 1 mL of DMF solution containing 0.2704 g BDO (3.0 mmol), and 3 mL of DMF solution containing 1.3774 g MDI (5.3 mmol). Stir at 70 °C for 5 min at 350 r / min. Add DBTDL. After 20 min, the viscosity increases dramatically. Add 1 mL of wash bottle DMF, followed by another 2 mL of DMF for dilution. After 10 min, add 2 mL of DMF solution containing 0.1968 g MDI (0.75 mmol). After 30 min, add 3 mL of DMF for dilution, followed by 4 mL of DMF solution containing 0.0604 g TMP (0.45 mmol). After 30 min, add 2 mL of a solution containing 0.0534 g of azophenylboronic acid monool (0.15 mmol). The DMF solution was reacted for 30 minutes. After the reaction, the polyurethane solution containing the azophenylboronic acid structure was introduced into a mold, and the solvent was dried in an oven to obtain a photoresponsive multifunctional polyurethane material based on azophenylboronic acid.

[0032] In summary, this invention successfully achieves synergistic optimization of high strength and photo-self-healing properties by introducing a photoactive azophenylboronic acid structure into a polyurethane system and leveraging the dynamic reversibility of borate ester bonds. Furthermore, this material possesses multiple functions, including photochromic behavior, photoresponsiveness, and humidity responsiveness, effectively overcoming the technical bottleneck of single-function existing photoresponsive self-healing materials and providing new ideas for the design of multifunctional smart materials.

[0033] In summary, this invention, by introducing a photoactive azophenylboronic acid structure into a polyurethane matrix and cleverly utilizing the photoinduced reversible isomerization effect of azophenyl as a "photoswitch," precisely controls the breaking and recombination of dynamic covalent bonds in boron-oxygen hexacyclic rings, thereby achieving a synergistic unity of high strength and efficient photo-induced self-healing properties. Furthermore, this material not only possesses photochromic properties but also exhibits multi-environmental responsiveness to light and humidity, successfully overcoming the limitations of traditional photoresponsive self-healing materials with their single function, and significantly improving the material's intelligent response level and application potential in complex environments.

[0034] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A photoresponsive multifunctional polyurethane material based on azophenylboronic acid, characterized in that, The polyurethane material is obtained by reacting diisocyanate, long-chain diol, chain extender, and monool containing azophenylboronic acid structure in a molar ratio of 1:0.25~0.5:0.2~0.7:0.03~0.

3. The general structural formula of the polyurethane is: ; In the formula, the value of n ranges from 3 to 40; In the formula, R1 is one or more of the following structural formulas; ； In the formula, R2 is one or more of the following structural formulas; ； In the formula, the value of x ranges from 4 to 30; In the formula, R3 is one or more of the following structural formulas; 。 2. The photoresponsive multifunctional polyurethane material based on azophenylboronic acid as described in claim 1, characterized in that, The general structural formula of the monool containing the azophenylboronic acid structure is as follows: 。 3. A method for preparing a photoresponsive multifunctional polyurethane material based on azophenylboronic acid as described in any one of claims 1-2, characterized in that, Includes the following steps: S1. Preparation of monools containing azophenylboronic acid structure: Monophenols containing azophenylboronic acid structure, chlorohexanol, potassium carbonate and potassium iodide were added to a round-bottom flask in a molar ratio of 1:1.1:2.4:0.4, dissolved in N,N-dimethylformamide, and stirred at 80°C for 10 hours. After the reaction was completed, the monools containing azophenylboronic acid structure were obtained by extraction, washing and drying. S2. Preparation of photoresponsive multifunctional polyurethane material based on azophenylboronic acid: Under nitrogen protection, diisocyanate, long-chain glycol, and butanediol were dissolved in N,N-dimethylformamide, and then dibutyltin dilaurate catalyst was added. The reaction was carried out at 70°C for 1-2 hours. Then, trimethylolpropane was added, and stirring was continued for 30 min. Immediately afterwards, a monool containing the azophenylboronic acid structure was added, and the reaction was continued for 30 min to obtain a polyurethane containing the azophenylboronic acid structure. The molar ratio of diisocyanate, long-chain glycol, chain extender, and monool containing the azophenylboronic acid structure was 1:0.25~0.5:0.2~0.7:0.03~0.

3. After the reaction was completed, the polyurethane solution containing the azophenylboronic acid structure was poured into a mold, and the solvent was dried in an oven to obtain a photoresponsive multifunctional polyurethane material based on azophenylboronic acid.

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