A high-toughness color-changing room-temperature self-repairing polyurethane elastic material and its preparation method and application

Abstract

The present invention discloses a high-toughness color-changing room-temperature self-healing polyurethane elastic material and its preparation method and application. The structural formula of the polyurethane elastomer material is as follows: wherein A is a diisocyanate group; B is a polyether polyol; n is a positive integer of 2 to 20, x is a positive integer of 10 to 80, y is a positive integer of 10-60, and z is a positive integer of 10 to 50. This application significantly enhances the tensile strength and fracture strain of the material obtained by incorporating a compound containing a quadruple hydrogen bond group into the polyurethane material, and also exhibits excellent self-healing performance and mechanical properties, making it have broad application prospects in the fields of intelligent materials such as sensors, bionic robots, and anti-counterfeiting devices; in addition, the preparation process of this application is simple and easy, and the obtained material has advantages such as structural uniformity and high repeatability, which is worthy of vigorous promotion and use.

Description

Technical Field

[0001] The invention belongs to the field of new material technology, and specifically relates to a high-toughness color-changing room-temperature self-repairing polyurethane elastic material and its preparation method and application. Background Art

[0002] Self-healing materials have attracted much attention due to their remarkable damage-repair capabilities, making them an extremely attractive research field. In recent years, researchers have continuously attempted to incorporate various functionalities into self-healing materials, including color-changing, actuation, and electrical conductivity. It is worth mentioning that the combination of self-healing and color-changing properties, on the one hand, provides the material with rich visual changes and information transmission capabilities; on the other hand, the self-healing properties ensure that the material can quickly restore its function and appearance when damaged. This combination makes the material more adaptable and flexible in dealing with complex environments and changing demands. On this basis, it is also essential to give the material excellent mechanical properties. Enhancing the mechanical properties of the material can give it a longer service life and more stable function.

[0003] However, most color-changing self-healing materials studied to date exhibit poor mechanical properties or require external energy to heal. Therefore, balancing high mechanical strength, color change, and self-healing capabilities is a highly significant research challenge. Polyurethane, due to its unique microphase separation microstructure, shows great potential in the production of self-healing materials. When the material is damaged, molecules within the soft domains rapidly respond by migrating to fill the damaged area, enabling self-healing. Meanwhile, the hard phase of polyurethane provides the material with physical and structural integrity. Serving as the material's backbone, the hard phase provides the necessary strength and stability, allowing polyurethane to maintain its self-healing properties without sacrificing mechanical properties. This balance makes polyurethane an ideal candidate for self-healing materials. Furthermore, the tunability of polyurethane opens up new possibilities for its application in the field of self-healing materials. By adjusting factors such as polyurethane synthesis conditions and monomer types and ratios, self-healing materials with specific properties can be customized.

[0004] At present, there is still a need to find a simple and efficient preparation method to synthesize color-changing polyurethane materials with room temperature self-healing properties and ensure that the material has good mechanical properties to meet its application in practical engineering. Summary of the Invention

[0005] In view of this, the object of the present invention is to provide a color-changing polyurethane material with room temperature self-repairing properties, and to ensure that the material has good mechanical properties and a high-toughness color-changing room temperature self-repairing polyurethane elastic material;

[0006] The purpose of the present invention is also to provide a preparation method of a high-toughness color-changing room-temperature self-healing polyurethane elastic material; the purpose of the present invention is also to provide an application of a high-toughness color-changing room-temperature self-healing polyurethane elastic material in sensors, soft robots, and anti-counterfeiting device intelligent materials.

[0007] In order to achieve the above object, the technical solution of the present invention is implemented as follows: a high-toughness color-changing room-temperature self-repairing polyurethane elastic material, the structural formula of the polyurethane elastomer material is as follows:

[0008]

[0009] Wherein, A is a diisocyanate group; B is a polyether polyol; n is a positive integer of 2 to 20, x is a positive integer of 10 to 80, y is a positive integer of 10 to 60, and z is a positive integer of 10 to 50.

[0010] Furthermore, the diisocyanate group is selected from at least one of substituted or unsubstituted phenyl, biphenyl, naphthyl, cyclohexyl or xylyl.

[0011] Furthermore, the hydroxyl-terminated polyether polyol is obtained by polymerization reaction of at least one selected from polyethylene glycol 200, polyethylene glycol 400, polyethylene glycol 600, polyethylene glycol 1000, polytetrahydrofuran 1000, polytetrahydrofuran 2000, polycaprolactone 1000 or polycaprolactone 2000.

[0012] Another technical solution of the present invention is achieved as follows: a method for preparing the above-mentioned high-toughness color-changing room temperature self-repairing polyurethane elastic material, the method specifically comprising the following steps:

[0013] S1, reacting diisocyanate, dried polyether polyol and ureidopyrimidone in the presence of an organotin catalyst to obtain a prepolymer;

[0014] S2, reacting the prepolymer with dihydroxylated tetraarylsuccinonitrile to obtain a crude material product;

[0015] S3. Add methanol to the crude material product. After the reaction is completed, remove the filtrate to obtain a high-toughness color-changing room-temperature self-repairing polyurethane elastic material.

[0016] Furthermore, in S1, the organic tin catalyst is selected from at least one of dibutyltin dioctylolaurate, dimethyltin dioctylodecanoate, tin methyl mercaptan, dibutyltin dilaurate, and di-n-octyltin dilaurate.

[0017] Furthermore, in S1, the molar ratio of the diisocyanate to the dihydroxylated tetraarylsuccinonitrile is 20:(1-4).

[0018] Furthermore, in said S1, the reaction temperature is 70-100°C,

[0019] Furthermore, in S1, the structural formula of the diisocyanate is:

[0020]

[0021] Furthermore, in S2, the molar ratio of the dihydroxylated tetraarylsuccinonitrile to the ureidopyrimidone is 1:(1-4).

[0022] Furthermore, in S2, the reaction temperature is 20-60°C.

[0023] The third technical solution of the present invention is achieved as follows: an application of the above-mentioned high-toughness color-changing room-temperature self-healing polyurethane elastic material in sensors, soft robots, and anti-counterfeiting device intelligent materials.

[0024] Compared with the existing technology, this application significantly enhances the tensile strength and fracture strain of the material obtained in this application by incorporating compounds containing quadruple hydrogen bond groups into polyurethane materials, and also exhibits excellent self-healing properties and mechanical properties, giving it broad application prospects in the fields of smart materials such as sensors, bionic robots, and anti-counterfeiting devices; in addition, the preparation process of this application is simple and easy, and the obtained material has advantages such as structural uniformity and high repeatability, and is worthy of vigorous promotion and use. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The above and other purposes, features, and advantages of the present application will become more apparent through a more detailed description of the embodiments of the present application in conjunction with the accompanying drawings. The accompanying drawings are intended to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the present application and do not constitute a limitation of the present application. In the drawings, the same reference numerals generally represent the same components or steps.

[0026] Figure 1 This is the infrared spectrum of the high-toughness color-changing room-temperature self-healing polyurethane elastic material TUPU75 obtained in Example 1;

[0027] Figure 2 This is a color change photo of the high-toughness color-changing room-temperature self-repairing polyurethane elastic material TUPU75 obtained in Example 1;

[0028] Figure 3 This is a picture of the thermally programmed high-toughness color-changing room-temperature self-healing polyurethane elastic material TUPU75 obtained in Example 1;

[0029] Figure 4 This is a picture of the scratch self-healing of the high-toughness color-changing room-temperature self-repairing polyurethane elastic material TUPU75 obtained in Example 1;

[0030] Figure 5 The stress-strain curves of the high-toughness color-changing room-temperature self-healing polyurethane elastic material obtained in Example 1 at different healing times after being cut into two sections are shown;

[0031] Figure 6 This is a picture of the high-toughness color-changing room-temperature self-repairing polyurethane elastic material obtained in Example 1, which can bear a load of 10 kg after healing at room temperature for 24 hours. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0033] The raw materials and auxiliary agents used in the embodiments of the present invention can be purchased or prepared by oneself.

[0034] The reaction equation of a high-toughness color-changing room-temperature self-repairing polyurethane elastic material provided by an embodiment of the present invention is as follows:

[0035]

[0036] A is a diisocyanate group selected from substituted or unsubstituted phenyl, biphenyl, naphthyl, cyclohexyl or xylyl; B is a polyether polyol selected from polyethylene glycol 200, 400, 600, 1000, polytetrahydrofuran 1000, 2000, polycaprolactone 1000, 2000; n is a positive integer of 2 to 20, x is a positive integer of 10 to 80, y is a positive integer of 10 to 60, and z is a positive integer of 10 to 50; the diisocyanate group is selected from at least one of substituted or unsubstituted phenyl, biphenyl, naphthyl, cyclohexyl or xylyl; and the hydroxyl-terminated polyether polyol is obtained by polymerization reaction of at least one of polyethylene glycol 200, polyethylene glycol 400, polyethylene glycol 600, polyethylene glycol 1000, polytetrahydrofuran 1000, polytetrahydrofuran 2000, polycaprolactone 1000 or polycaprolactone 2000.

[0037] The present invention also provides a method for preparing the high-toughness color-changing room-temperature self-repairing polyurethane elastic material, which specifically includes the following steps:

[0038] S1. reacting a diisocyanate, a dried polyether polyol, and a ureidopyrimidone in the presence of an organotin catalyst to obtain a prepolymer; wherein the molar ratio of the diisocyanate to the tetraarylsuccinonitrile is 20:(1-4); and the reaction temperature is 70-100° C.;

[0039] S2, reacting the prepolymer with tetraarylsuccinonitrile to obtain a crude material product; the molar ratio of the tetraarylsuccinonitrile to the ureidopyrimidone is 1: (0.25-4); the reaction temperature is 20-60°C

[0040] S3. Add methanol to the crude material product. After the reaction is completed, remove the filtrate to obtain a high-toughness color-changing room-temperature self-repairing polyurethane elastic material.

[0041] In the specific implementation process of the embodiment of the present invention: in S1, the structural formula of the diisocyanate is:

[0042]

[0043] The following are specific embodiments

[0044] Example 1

[0045] The color-changing room-temperature self-repairing polyurethane elastic material provided in Example 1 was prepared according to the following steps:

[0046] S1. Weigh 1 g of polytetrahydrofuran 1000 (1 mmol) into a 10 mL reaction flask. Add 1 mL of nitrogen-dimethylacetamide to dissolve the mixture and stir for 1 minute. Weigh 126.9 mg (0.75 mmol) of ureidopyrimidone (UPy) into the flask and dissolve it in 0.5 mL of nitrogen-dimethylacetamide. Weigh 551 mg (2.1 mmol) of 4,4'-diisocyanatodicyclohexylmethane (HMDI) into the flask and dissolve it in 1 mL of solvent. Then, dropwise add 20 μL of dibutyltin dilaurate (DBTDL) catalyst and quickly evacuate the argon atmosphere. The reaction mixture was placed in an oil bath at 75°C for three hours. The reaction solution gradually changed from a turbid white color to a clear, colorless solution.

[0047] S2. Dissolve 141.5 mg of tetraarylsuccinonitrile (0.25 mmol) in nitrogen-dimethylacetamide solvent. After 3 hours of reaction, add the dissolved tetraarylsuccinonitrile to the reaction solution, transfer the reaction mixture to room temperature, and stir at room temperature for 12 hours.

[0048] S3. When the reaction is almost complete, add 1 ml of anhydrous methanol and stir for 5 minutes to remove any unreacted isocyanate. Discard the upper layer of solution and pour the lower viscous liquid onto a glass plate. Place the plate in a vacuum drying oven for 12 hours to obtain a polyurethane material.

[0049] Figure 1 The infrared spectrum of the polyurethane elastic material TUPU-XX obtained in Example 1; Figure 1 It can be seen that: at 3330cm -1The absorption peak at 1700 cm -1 The carbonyl peak observed at 2262 cm further verifies that the conversion of isocyanate has been successfully achieved. In addition, a significant evidence is that we did not observe the carbonyl peak at 2262 cm -1 The characteristic absorption peak of N=C=O group was found at 3458cm, which strongly proved that there was no isocyanate residue in the product. -1 The characteristic absorption peak at has disappeared, which clearly shows that all the alcohol raw materials involved in the reaction have been completely converted.

[0050] Figure 2 This is a color change photo of the polyurethane elastic material TUPU75 prepared in Example 1; Figure 2 It can be seen that the multifunctional polyurethane elastic material TUPU75 obtained in Example 1 can change its color from yellow to red when heated.

[0051] Figure 3 This is a thermal programming image of the polyurethane elastic material TUPU75 prepared in Example 1; by analyzing Figure 3 It can be seen that the polyurethane elastic material TUPU75 obtained in Example 1 has thermo-programmable properties. Under heating conditions of 60°C, the material is deformed into an S-shaped spiral, and then quickly cooled to 20°C to lock this temporary shape. It is worth noting that this temporary shape can remain stable at room temperature. When heated to 60°C again, the material gradually shows its memory properties and returns to its original shape. In order to further clearly demonstrate its shape memory behavior, TUPU-75 was made into a petal-shaped film and programmed into a bud shape by heating. Subsequently, during the reheating process, the material simulated the process of a flower blooming, vividly demonstrating its excellent shape memory properties.

[0052] Figure 4 This is a scratch self-healing picture of the polyurethane elastic material TUPU75 prepared in Example 1; Figure 4 It can be seen that the multifunctional polyurethane elastic material TUPU75 obtained in Example 1 has excellent self-healing properties. The scratches on the material almost disappeared after ten minutes of healing at room temperature.

[0053] Figure 5 The original stress-strain curve of the polyurethane elastic material TUPU75 prepared in Example 1 and the stress-strain curves after healing at room temperature 1 hour, 6 hours and 24 hours after cutting; by analyzing Figure 5It can be seen that the polyurethane elastic material TUPU75 prepared in Example 1 has excellent mechanical properties (stress: 18.05 MPa, strain: 1241%) and self-repairing ability (the healing efficiency can reach 96.7% after repair for 24 hours at room temperature).

[0054] Figure 6 This is a picture of the polyurethane elastic material prepared in Example 1 that can bear a load of 10 kg after being completely broken and healed for 24 hours at room temperature. Figure 6 It can be seen that this weight is one hundred thousand times its own weight, which further proves that it has excellent mechanical properties and self-healing properties.

[0055] Example 2

[0056] The color-changing, room-temperature self-healing polyurethane elastic material provided in Example 2 differs from Example 1 only in that polytetrahydrofuran 1000 is replaced with polyethylene glycol 1000. The types, amounts, and preparation methods of the remaining components are the same as those in Example 1. The material exhibits similar color-changing, shape-programmable, and healing properties as those in Example 1; detailed properties are shown in Table 1 below.

[0057] Example 3

[0058] Example 3 provides a color-changing, room-temperature self-healing polyurethane elastic material. This material differs from Example 1 only in that dicyclohexylmethane diisocyanate is replaced with isophorone isocyanate. The types, amounts, and preparation methods of the remaining components are the same as those in Example 1. The material exhibits similar color-changing, shape-programmable, and healing properties as those in Example 1; detailed properties are shown in Table 1 below.

[0059] Example 4

[0060] The color-changing, room-temperature self-healing polyurethane elastic material provided in Example 4 differs from that in Example 1 only in that the molar ratio of dihydroxylated tetraarylsuccinonitrile to ureidopyrimidone is 4:1. The types, amounts, and preparation methods of the remaining components are the same as in Example 1. The material exhibits similar color-changing, shape-programmable, and healing properties as in Example 1; detailed properties are shown in Table 1 below.

[0061] Example 5

[0062] The color-changing, room-temperature self-healing polyurethane elastic material provided in Example 5 differs from Example 1 only in that the molar ratio of dihydroxylated tetraarylsuccinonitrile to ureidopyrimidone is 3:1. The types, amounts, and preparation methods of the remaining components are the same as in Example 1. The material exhibits similar color-changing, shape-programmable, and healing properties as in Example 1; detailed properties are shown in Table 1 below.

[0063] Example 6

[0064] The color-changing, room-temperature self-healing polyurethane elastic material provided in Example 6 differs from that in Example 1 only in that the molar ratio of dihydroxylated tetraarylsuccinonitrile to ureidopyrimidone is 1:1. The types, amounts, and preparation methods of the remaining components are the same as in Example 1. The material exhibits similar color-changing, shape-programmable, and healing properties as in Example 1; detailed properties are shown in Table 1 below.

[0065] Example 7

[0066] The color-changing, room-temperature self-healing polyurethane elastic material provided in Example 7 differs from that in Example 1 only in that the molar ratio of dihydroxylated tetraarylsuccinonitrile to ureidopyrimidone is 1:4. The types, amounts, and preparation methods of the remaining components are the same as in Example 1. The material exhibits similar color-changing, shape-programmable, and healing properties as in Example 1; detailed properties are shown in Table 1 below.

[0067] Example 8

[0068] The color-changing, room-temperature self-healing polyurethane elastic material provided in Example 8 differs from Example 1 only in that polytetrahydrofuran 1000 is replaced with polytetrahydrofuran 2000. The types, amounts, and preparation methods of the remaining components are the same as those in Example 1. The material exhibits similar color-changing, shape-programmable, and healing properties as those in Example 1; detailed properties are shown in Table 1 below.

[0069] Example 9

[0070] The color-changing, room-temperature self-healing polyurethane elastic material provided in Example 9 differs from Example 1 only in that polytetrahydrofuran 1000 is replaced with polycaprolactone 1000. The types, amounts, and preparation methods of the remaining components are the same as those in Example 1. The material exhibits similar color-changing, shape-programmable, and healing properties as those in Example 1; detailed properties are shown in Table 1 below.

[0071] Example 10

[0072] The color-changing, room-temperature self-healing polyurethane elastic material provided in Example 10 differs from Example 1 only in that dibutyltin dilaurate is replaced with di-ortho-zinc-tin dilaurate. The types, amounts, and preparation methods of the remaining components are the same as in Example 1. The material exhibits similar color-changing, shape-programmable, and healing properties as in Example 1; detailed properties are shown in Table 1 below.

[0073] Example 11

[0074] The color-changing, room-temperature self-healing polyurethane elastic material provided in Example 11 differs from Example 1 only in that the reaction temperature in step (1) is changed from 75°C to 100°C. The types, amounts, and preparation methods of the remaining components are the same as those in Example 1. The material exhibits similar color-changing, shape-programmable, and healing properties as those in Example 1; detailed properties are shown in Table 1 below.

[0075] Example 12

[0076] The color-changing, room-temperature self-healing polyurethane elastic material provided in Example 12 differs from Example 1 only in that the reaction temperature in step (2) is changed from 25°C to 50°C. The types, amounts, and preparation methods of the remaining components are the same as those in Example 1. The material exhibits similar color-changing, shape-programmable, and healing properties as those in Example 1; detailed properties are shown in Table 1 below.

[0077] Table 1 Performance test results of color-changing room temperature self-repairing polyurethane elastic materials obtained in Examples 1-12

[0078]

[0079]

[0080] By analyzing and comparing the experimental data in Table 1 above, it can be seen that the color-changing room-temperature self-healing polyurethane elastic material obtained in this application has excellent mechanical strength and tensile strain when the healing temperature remains unchanged, thereby laying a solid foundation for expanding its use.

[0081] In summary, this application significantly enhances the tensile strength and fracture strain of the material obtained in this application by incorporating compounds containing quadruple hydrogen bond groups into polyurethane materials, and also exhibits excellent self-healing properties and mechanical properties, giving it broad application prospects in the fields of smart materials such as sensors, bionic robots, and anti-counterfeiting devices; in addition, the preparation process of this application is simple and easy, and the obtained material has advantages such as structural uniformity and high repeatability, and is worthy of vigorous promotion and use.

[0082] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A method for preparing a high-toughness color-changing room-temperature self-repairing polyurethane elastic material, characterized in that: The method specifically comprises the following steps: S1, diisocyanate, dried polyether polyol and Reacting under an organic tin catalyst to obtain a prepolymer; S2, the prepolymer and the molecular formula The dihydroxylated tetraarylsuccinonitrile is reacted to obtain a crude material; S3. Adding methanol to the crude material product, and after the reaction is completed, removing the filtrate to obtain a high-toughness color-changing room-temperature self-repairing polyurethane elastic material; Wherein, the molar ratio of the diisocyanate to the dihydroxylated tetraaryl succinonitrile is 20:(1-4); the dihydroxylated tetraaryl succinonitrile and The molar ratio is 1:(0.25~4).

2. The method for preparing the high-toughness color-changing room-temperature self-repairing polyurethane elastic material according to claim 1, characterized in that: In S1, the organic tin catalyst is selected from at least one of dibutyltin dioctylolaurate, dimethyltin dioctylodecanoate, tin methyl mercaptan, dibutyltin dilaurate, and di-n-octyltin dilaurate.

3. The method for preparing the high-toughness color-changing room-temperature self-repairing polyurethane elastic material according to claim 1, characterized in that: In S1, the polyether polyol is selected from at least one of polyethylene glycol 200, polyethylene glycol 400, polyethylene glycol 600, polyethylene glycol 1000, polytetrahydrofuran 1000, and polytetrahydrofuran 2000.

4. The method for preparing the high-toughness color-changing room-temperature self-repairing polyurethane elastic material according to claim 1, characterized in that: In the step S1, the reaction temperature is 70-100°C.

5. The method for preparing the high-toughness color-changing room-temperature self-repairing polyurethane elastic material according to claim 3, characterized in that: In S1, the structural formula of the diisocyanate is:

6. The method for preparing the high-toughness color-changing room-temperature self-repairing polyurethane elastic material according to claim 1, characterized in that: The dihydroxylated tetraarylsuccinonitrile and The amount ratio of the substance is 1: (1 to 4); in S2, the reaction temperature is 20 to 60°C.

7. A high-toughness color-changing room-temperature self-repairing polyurethane elastic material, characterized in that: The method is prepared according to any one of claims 1 to 6.

8. An application of the high-toughness color-changing room-temperature self-repairing polyurethane elastic material as claimed in claim 7 in sensors, soft robots, and intelligent materials for anti-counterfeiting devices.

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