High-strength self-repairing polyurethane ion elastomer as well as preparation method and application thereof

Abstract

The invention discloses a preparation method of a high-strength self-repairing polyurethane ion elastomer, and the preparation method of the high-strength self-repairing polyurethane ion elastomer specifically comprises the following steps: preparing high-strength room-temperature self-repairing polyurethane, and introducing a conductive filler bis (trifluoromethane sulfonimide) lithium and a reinforcing agent carboxylated multi-walled carbon nanotube into the high-strength room-temperature self-repairing polyurethane. The invention further provides the high-strength self-repairing polyurethane ion elastomer prepared through the method and application of the high-strength self-repairing polyurethane ion elastomer. The high-strength self-repairing polyurethane ion elastomer and the preparation method and application of the high-strength self-repairing polyurethane ion elastomer solve the problem that contradictions exist among rapid self-repairing, electrical conductivity and high strength of an existing polyurethane material.

Description

Technical Field

[0001] The present invention belongs to the field of material technology, and specifically relates to a high-strength self-healing polyurethane ion elastomer, and also relates to a preparation method and application of the above-mentioned polyurethane ion elastomer. Background Art

[0002] With the progress of human society, the demand for functional polymer materials is also increasing. Polyurethane has been widely used in various fields due to its advantages such as stable mechanical properties, good solvent resistance, wear resistance, and controllable structure and performance. At the same time, the polyurethane elastomer material chain segments contain rich functional groups, which can be functionalized through physical and chemical modifications. Therefore, the research on functional polyurethane materials is very mature. According to the different application scenarios of functional polyurethane, it can be functionalized to achieve a wider range of applications. Most polyurethane materials will inevitably be damaged during processing and use. The damaged materials often need to be replaced or discarded, which causes waste of resources and potential environmental pollution. Utilizing the dynamic reversible interaction of polymer chains to achieve polymer damage repair can extend the service life of polyurethane materials, improve their reliability and durability, and reduce resource waste and environmental pollution.

[0003] Currently, methods for preparing self-healing materials fall into two categories: one involves incorporating functional substances within the material to achieve self-healing, also known as externally assisted self-healing; the other involves providing energy to the system, causing the material to undergo covalent or non-covalent interactions, also known as intrinsic self-healing (Diels-Alder (DA) reactions, dynamic covalent bonds such as diene bonds, BO bonds, acylhydrazone bonds, imine bonds, and disulfide bonds, and dynamic non-covalent bonds such as hydrogen bonds, coordination bonds, and π-π interactions). Due to their site-specificity, efficient repair capabilities, simple production and processing (eliminating complex steps such as pre-embedding the repair agent), and environmental friendliness, the preparation of intrinsically self-healing polymer materials has become a hot topic among researchers and is being applied in coatings, biomimetic materials, aerospace and aviation materials, electronic components, and other fields.

[0004] However, based on the current research status, the preparation of polyurethane with room temperature self-healing ability, high conductivity, and high strength must resolve the contradiction between rapid self-healing, conductivity, and high strength. Ion-conductive polyurethane materials with high-strength self-healing ability must have the following characteristics: 1. Strict control of the molecular structure design of the self-healing polyurethane to ensure the rapid migration of molecules during the self-healing process; 2. A sufficient number of reversible chemical bonds (covalent bonds or non-covalent bonds) to ensure the bonding strength between molecules; 3. While achieving dynamic construction, the self-healing polyurethane needs to have sufficient active sites to provide sites for ion migration.

[0005] Most existing self-healing polymer materials can achieve efficient self-healing capabilities, but this inevitably comes at the expense of their mechanical properties. Furthermore, most current intrinsically self-healing polymer materials require external energy to achieve self-healing, making it difficult to self-heal at room temperature to reduce energy consumption. While research has been conducted on the application of self-healing materials in the field of flexible smart materials, achieving a balance between electrical conductivity and self-healing capabilities remains a major technical challenge in the field of composite materials. Summary of the Invention

[0006] The first object of the present invention is to provide a method for preparing a high-strength self-healing polyurethane ion elastomer, thereby resolving the contradiction between rapid self-healing, electrical conductivity, and high strength in existing polyurethane materials.

[0007] The second object of the present invention is to provide a high-strength self-healing polyurethane ion elastomer prepared by the above method.

[0008] The third object of the present invention is to provide an application of the high-strength self-healing polyurethane ion elastomer.

[0009] The first technical solution adopted by the present invention is: a method for preparing a high-strength self-healing polyurethane ion elastomer. The specific method for preparing the high-strength self-healing polyurethane ion elastomer is as follows: prepare high-strength room-temperature self-healing polyurethane, and introduce conductive filler lithium bis(trifluoromethanesulfonylimide) and reinforcing agent carboxylated multi-walled carbon nanotubes into it.

[0010] The first technical solution adopted by the present invention is also characterized in that: Furthermore, the preparation method of the high-strength self-repairing polyurethane ion elastomer is specifically prepared according to the following steps: Step 1: adding polytetrahydrofuran and diisocyanate to an organic solvent for reaction to obtain a polyurea prepolymer, then adding a certain proportion of a multi-hydrogen bond acceptor and donor chain extender for chain extension, and finally polymerizing with a certain amount of a trifunctional polymer to obtain a high-strength room-temperature self-healing polyurethane elastomer; Step 2: dissolving the polyurethane elastomer prepared in step 1 in an organic solvent, adding a certain amount of lithium bis(trifluoromethanesulfonyl)imide, and dispersing the mixture evenly; Step 3. Based on the conductive elastomer prepared in step 2, a certain amount of carboxylated multi-walled carbon nanotubes is uniformly dispersed in an organic solvent. After ultrasonication for 30 minutes, the nanotubes are added to the dispersion prepared in S2 and, after complete dispersion, a film is formed at room temperature to obtain a high-strength, room-temperature self-healing polyurethane ion conductive elastomer.

[0011] Furthermore, in step 1, the diisocyanate is selected from one or more of hexamethylene diisocyanate, isophorone diisocyanate, 4,4-diphenylmethane diisocyanate and toluene diisocyanate; polytetrahydrofuran needs to be dehydrated at high temperature, and the reaction temperature for generating the polyurethane prepolymer is 60-90° C. and the reaction time is 2-4 hours; the chain extender for the multi-hydrogen bond acceptor and donor is adipic acid dihydrazide, and the trifunctional polymer is 2-amino-2-methyl-1,3-propanediol.

[0012] Furthermore, the molar ratio of the chain extender of the multi-hydrogen bond acceptor and donor to polytetrahydrofuran in step 1 is 1:0.8-1.2, and the molar ratio of the multifunctional cross-linking agent in step 1 is 0.1-0.69 of the total amount.

[0013] Furthermore, the organic solvent in step 1 is selected from one or more of acetone, butanone, ether, toluene, xylene, tetrahydrofuran, ethylene glycol, N,N-dimethylformamide and N,N-dimethylacetamide.

[0014] Furthermore, the mass ratio of lithium bis(trifluoromethanesulfonyl)imide in step 2 is 10% to 30% of the mass of the added polyurethane elastomer.

[0015] Furthermore, the mass ratio of the carboxylated multi-walled carbon nanotubes in step 3 is 10% to 30% of the mass of the polyurethane elastomer.

[0016] The second technical solution adopted by the present invention is: a high-strength self-repairing polyurethane ion elastomer prepared by the above method.

[0017] The third technical solution adopted by the present invention is: application of the above-mentioned high-strength self-healing polyurethane ion elastomer in a flexible sensor.

[0018] The fourth technical solution adopted by the present invention is: application of the above-mentioned high-strength self-healing polyurethane ion elastomer in energy harvesting.

[0019] The beneficial effects of the present invention are: (1) The high-strength self-healing polyurethane ionomer of the present invention has a spider-web-like structure, which can achieve the synergy of high strength and self-healing ability by forming a rigid β-pleated crystal region (providing strength) and a flexible amorphous region (imparting elasticity). The β-pleated crystal region is rich in hydrogen bonds. Under the action of external force, the hydrogen bonds break and reorganize, achieving self-healing and energy dissipation. By imitating this structure, multiple dense hydrogen bonds are introduced into the polyurethane, thereby realizing the construction of a multi-hydrogen bond cross-linked self-healing polyurethane, achieving room temperature self-healing.

[0020] (2) The present invention introduces multi-hydrogen bond crosslinking and covalent crosslinking into polyurethane, and achieves a balance between self-repair and high strength through a double crosslinking system.

[0021] (3) The present invention introduces lithium bis(trifluoromethanesulfonyl imide) into a high-strength, room-temperature self-healing polyurethane elastomer based on multiple hydrogen bonds to achieve ionic conductivity. In order to further enhance the conductivity and improve the strength of the device, carboxylated multi-walled carbon nanotubes are introduced to achieve a balance between self-healing ability and conductivity. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a synthetic route for the high-strength, room-temperature self-healing polyurethane elastomer prepared in Example 1 of the present invention.

[0023] Figure 2 The stress-strain curves of the high-strength room-temperature self-healing polyurethane elastomer prepared by the present invention with different ratios of ADH and AMPD; Figure 3 Ultra-depth-of-field microscope images and actual images of the high-strength, room-temperature self-healing polyurethane elastomer prepared in Example 1 of the present invention; Figure 4 This is the self-repairing stress-strain curve of the high-strength room-temperature self-repairing polyurethane elastomer prepared in Example 1 of this method; Figure 5 This is a photo of the self-repairing and lighting process of the high-strength room-temperature self-repairing polyurethane ion-conductive elastomer prepared in Example 1 of the present invention; Figure 6 This is a graph showing the strain sensing performance of the high-strength, room-temperature self-healing polyurethane ion-conductive elastomer prepared in Example 1 of the present invention; Figure 7 This is a diagram of the photothermal conversion capability of the high-strength, room-temperature self-healing polyurethane ion-conductive elastomer prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0024] The present invention will be further described below with reference to the accompanying drawings and examples.

[0025] The present invention provides a method for preparing a high-strength self-repairing polyurethane ion elastomer. The specific preparation process is as follows: Figure 1 As shown, the prepared high-strength self-healing polyurethane ion elastomer has excellent properties, specifically as Figure 2-7 As shown, the present invention also provides the application of high-strength room-temperature self-healing polyurethane ion-conductive elastomer in flexible sensors and the application of high-strength room-temperature self-healing polyurethane ion-conductive elastomer in energy harvesting.

[0026] Example 1 This embodiment provides a high-strength, room-temperature self-healing polyurethane ion-conductive elastomer for use in flexible sensors. The preparation method of the high-strength, room-temperature self-healing polyurethane ion-conductive elastomer includes the following steps: (1) Add NH2-PTMG-NH2 (polytetramethylenetetramethylene ether glycol) (5g), IPDI (isophorone diisocyanate) (3.53g) and 10mL DMAc (N, N-dimethylacetamide) into a three-necked flask and stir mechanically. Slowly inject argon into the system to make the entire system in an inert gas state. Place the flask in a water bath and heat it to 80℃. Keep the temperature for 6h, add adipic acid dihydrazide (ADH) to the flask at a molar ratio of 1:1 with PTMG, add 10mL DMAc and keep the temperature for 6h, add 2-amino-2-methyl-1,3-propanediol (AMPD) to the reaction system at a molar ratio of 0.69 to the total amount of the reaction system, and keep the temperature for 4 hours. After the reaction is completed, dry at 60℃ to obtain a high-strength room temperature self-healing polyurethane elastomer; (2) Take 2 g of the polyurethane elastomer prepared in S1 and dissolve it in tetrahydrofuran (THF). Add lithium bis(trifluoromethanesulfonyl)imide at a polyurethane mass ratio of 30% and disperse it evenly.

[0027] (3) Based on the conductive elastomer prepared by S2, carboxylated multi-walled carbon nanotubes with a polyurethane mass ratio of 30% were uniformly dispersed in THF. After ultrasonic treatment for 30 minutes, they were added to the dispersion prepared by S2. After complete dispersion, the film was formed at room temperature. A high-strength, room-temperature self-healing polyurethane ion conductive elastomer was obtained.

[0028] Figure 2 The stress-strain curves of the high-strength room-temperature self-healing polyurethane elastomer prepared by the present invention with different ratios of ADH and AMPD; Figure 3 Ultra-depth-of-field microscope images and actual images of the high-strength, room-temperature self-healing polyurethane elastomer prepared in Example 1 of the present invention; Figure 4 This is the self-repairing stress-strain curve of the high-strength room-temperature self-repairing polyurethane elastomer prepared in Example 1 of this method; Figure 5 This is a photo of the self-repairing and lighting process of the high-strength room-temperature self-repairing polyurethane ion-conductive elastomer prepared in Example 1 of the present invention; Figure 6 This is a graph showing the strain sensing performance of the high-strength, room-temperature self-healing polyurethane ion-conductive elastomer prepared in Example 1 of the present invention; Figure 7 This is a diagram of the photothermal conversion capability of the high-strength, room-temperature self-healing polyurethane ion-conductive elastomer prepared in Example 1 of the present invention.

[0029] from Figure 2 It can be seen that the prepared polyurea has good mechanical properties, and with the increase of ADH content, the strength of polyurethane is further increased, which can provide technical support for high-strength self-healing polyurethane.

[0030] from Figure 3It can be seen that the prepared polyurethane has excellent room temperature self-healing ability, and can achieve bending and other movements after 24 hours of repair at room temperature.

[0031] from Figure 4 It can be seen that the prepared high-strength self-healing polyurethane has a high self-healing efficiency, and can basically restore the original mechanical properties after repair at room temperature for 24 hours.

[0032] from Figure 5 It can be seen that the prepared high-strength self-healing polyurethane elastomer has excellent self-healing and conductive properties. After being cut off and then contacted again, the conductive ability can be restored in a short time and the LED lamp can be lit.

[0033] from Figure 6 It can be seen that the prepared high-strength self-healing polyurethane ion conductive elastomer has excellent sensing ability and can effectively monitor signals of different strains.

[0034] from Figure 7 It can be seen that the prepared high-strength self-healing polyurethane ion conductive elastomer has excellent photothermal conversion ability, and the surface temperature can reach above 140°C within 120s.

[0035] Example 2 This embodiment provides a high-strength, room-temperature self-healing polyurethane ion-conductive elastomer for use in flexible sensors. The preparation method of the high-strength, room-temperature self-healing polyurethane ion-conductive elastomer includes the following steps: (1) Add NH2-PTMG-NH2 (polytetramethylenetetramethylene ether glycol) (5g), IPDI (isophorone diisocyanate) (3.53g) and 10mL DMAc (N, N-dimethylacetamide) into a three-necked flask and stir mechanically. Slowly inject argon into the system to make the entire system in an inert gas state. Place the flask in a water bath and heat it to 80℃. Keep the temperature for 6h, add adipic acid dihydrazide (ADH) to the flask at a molar ratio of 1:0.8 to PTMG, add 10mL DMAc and keep the temperature for 6h, add 2-amino-2-methyl-1,3-propanediol (AMPD) to the reaction system at a molar ratio of 0.69 to the total amount of the reaction system, and keep the temperature for 4 hours. After the reaction is completed, dry at 60℃ to obtain a high-strength room temperature self-healing polyurethane elastomer; (2) Take 2 g of the polyurethane elastomer prepared in S1 and dissolve it in tetrahydrofuran (THF). Add lithium bis(trifluoromethanesulfonyl)imide at a polyurethane mass ratio of 30% and disperse it evenly.

[0036] (3) Based on the conductive elastomer prepared by S2, carboxylated multi-walled carbon nanotubes with a polyurethane mass ratio of 30% were uniformly dispersed in THF. After ultrasonic treatment for 30 minutes, they were added to the dispersion prepared by S2. After complete dispersion, the film was formed at room temperature. A high-strength, room-temperature self-healing polyurethane ion conductive elastomer was obtained.

[0037] Example 3 This embodiment provides a high-strength, room-temperature self-healing polyurethane ion-conductive elastomer for use in flexible sensors. The preparation method of the high-strength, room-temperature self-healing polyurethane ion-conductive elastomer includes the following steps: (1) Add NH2-PTMG-NH2 (polytetramethylene glycol) (5g), IPDI (isophorone diisocyanate) (3.53g) and 10mL DMAc (N, N-dimethylacetamide) into a three-necked flask and stir mechanically. Slowly inject argon into the system to make the entire system in an inert gas state. Place the flask in a water bath and heat it to 80℃. Keep the temperature for 6h, add adipic acid dihydrazide (ADH) to the flask at a molar ratio of 1:1.2 to PTMG, add 10mL DMAc and keep the temperature for 6h, add 2-amino-2-methyl-1,3-propanediol (AMPD) to the reaction system at a molar ratio of 0.69 to the total amount of the reaction system, and keep the temperature for 4 hours. After the reaction is completed, dry at 60℃ to obtain a high-strength room temperature self-healing polyurethane elastomer; (2) Take 2 g of the polyurethane elastomer prepared in S1 and dissolve it in tetrahydrofuran (THF). Add lithium bis(trifluoromethanesulfonyl)imide at a polyurethane mass ratio of 30% and disperse it evenly.

[0038] (3) Based on the conductive elastomer prepared by S2, carboxylated multi-walled carbon nanotubes with a polyurethane mass ratio of 30% were uniformly dispersed in THF. After ultrasonic treatment for 30 minutes, they were added to the dispersion prepared by S2. After complete dispersion, the film was formed at room temperature. A high-strength, room-temperature self-healing polyurethane ion conductive elastomer was obtained.

[0039] Example 4 This embodiment provides a high-strength, room-temperature self-healing polyurethane ion-conductive elastomer for use in flexible sensors. The preparation method of the high-strength, room-temperature self-healing polyurethane ion-conductive elastomer includes the following steps: (1) Add NH2-PTMG-NH2 (polytetramethylene glycol) (5 g), IPDI (isophorone diisocyanate) (3.53 g) and 10 mL DMAc (N, N-dimethylacetamide) into a three-necked flask and stir mechanically. Slowly inject argon into the system to make the entire system in an inert gas state. Place the flask in a water bath and heat it to 80 ° C. Keep the temperature for 6 hours, add adipic acid dihydrazide (ADH) to the flask at a molar ratio of 1 to PTMG, add 10 mL DMAc and keep the temperature for 6 hours, add 2-amino-2-methyl-1,3-propanediol (AMPD) to the reaction system at a molar ratio of 0.39 to the total amount of the reaction system, and keep the temperature for 2 hours. After the reaction is completed, dry at 90 ° C to obtain a high-strength room temperature self-healing polyurethane elastomer; (2) Take 2 g of the polyurethane elastomer prepared in S1 and dissolve it in tetrahydrofuran (THF). Add lithium bis(trifluoromethanesulfonyl)imide at a polyurethane mass ratio of 10% and disperse it evenly.

[0040] (3) Based on the conductive elastomer prepared by S2, carboxylated multi-walled carbon nanotubes with a polyurethane mass ratio of 10% were uniformly dispersed in THF. After ultrasonic treatment for 30 minutes, they were added to the dispersion prepared by S2. After complete dispersion, film formation was carried out at room temperature. A high-strength, room-temperature self-healing polyurethane ion conductive elastomer was obtained.

[0041] Example 5 This embodiment provides a high-strength, room-temperature self-healing polyurethane ion-conductive elastomer for use in flexible sensors. The preparation method of the high-strength, room-temperature self-healing polyurethane ion-conductive elastomer includes the following steps: (1) Add NH2-PTMG-NH2 (polytetramethylene glycol) (5g), IPDI (isophorone diisocyanate) (3.53g) and 10mL DMAc (N, N-dimethylacetamide) into a three-necked flask and stir mechanically. Slowly inject argon into the system to make the entire system in an inert gas state. Place the flask in a water bath and heat it to 80℃. Keep the temperature for 6h, add adipic acid dihydrazide (ADH) to the flask at a molar ratio of 1:1 with PTMG, add 10mL DMAc and keep the temperature for 6h, add 2-amino-2-methyl-1,3-propanediol (AMPD) to the reaction system at a molar ratio of 0.1 to the total amount of the reaction system, and keep the temperature for 3 hours. After the reaction is completed, dry at 75℃ to obtain a high-strength room temperature self-healing polyurethane elastomer; (2) Take 2 g of the polyurethane elastomer prepared in S1 and dissolve it in tetrahydrofuran (THF). Add lithium bis(trifluoromethanesulfonyl)imide at a polyurethane mass ratio of 20% and disperse it evenly.

[0042] (3) Based on the conductive elastomer prepared by S2, carboxylated multi-walled carbon nanotubes with a polyurethane mass ratio of 20% were uniformly dispersed in THF. After ultrasonic treatment for 30 minutes, they were added to the dispersion prepared by S2. After complete dispersion, film formation was carried out at room temperature. A high-strength, room-temperature self-healing polyurethane ion conductive elastomer was obtained.

[0043] Effect verification Experimental subjects: Example 1-Example 5.

[0044] Experimental method: Mechanical properties test: The prepared polyurethane was cut into 1×4 strip samples and tensile tests were carried out at room temperature using a servo-controlled high and low temperature tensile testing machine. Uniaxial tension and loading-unloading cycles were performed using a 50 mm·min -1 The elastic modulus is determined by the initial slope of the stress-strain curve. The toughness is obtained by integrating the area under the stress-strain curve, which is a test of its mechanical properties.

[0045] Self-healing performance test method: The prepared polyurethane was cut into 1×4 strip samples, cut in the middle with a knife, and then contacted at room temperature. After contact time of 2h, 8h, 12h, 24h, and 48h, the mechanical properties were tensile tested in a servo-controlled high and low temperature tensile testing machine to characterize its self-healing ability. At the same time, its repair status was observed under an ultra-depth of field microscope at different contact times.

[0046] Table 2 Mechanical properties of polyurethane in different examples

[0047] As shown in Table 1, with the increase of crosslinking degree and ADH content, the strength and toughness of the self-healing polyurethane increase, showing excellent mechanical properties.

[0048] Example 6 The application of the high-strength room-temperature self-healing polyurethane ion-conductive elastomer of the present invention in flexible sensors is shown in Examples 1-5.

[0049] Example 7 The high-strength, room-temperature self-healing polyurethane ion-conductive elastomer of this invention can be used in energy harvesting. For example, it can be combined with other energy harvesting technologies (such as solar energy and electromagnetic power generation) to achieve multi-source energy supply. It can also be used as a self-powered sensor or energy source to harvest energy from human motion (such as walking and gestures) or environmental vibration to power health monitoring devices. It can also provide sustainable energy for distributed sensor networks, reducing battery dependence.

Claims

1. A method for preparing a high-strength self-repairing polyurethane ion elastomer, characterized in that: The preparation method of the high-strength self-repairing polyurethane ion elastomer is specifically as follows: preparing high-strength room-temperature self-repairing polyurethane, and introducing conductive filler lithium bis(trifluoromethanesulfonylimide) and reinforcing agent carboxylated multi-walled carbon nanotubes into it.

2. The method for preparing a high-strength self-repairing polyurethane ion elastomer according to claim 1, characterized in that: Specifically prepared according to the following steps: Step 1: adding polytetrahydrofuran and diisocyanate to an organic solvent for reaction to obtain a polyurea prepolymer, then adding a certain proportion of a multi-hydrogen bond acceptor and donor chain extender for chain extension, and finally polymerizing with a certain amount of a trifunctional polymer to obtain a high-strength room-temperature self-healing polyurethane elastomer; Step 2: dissolving the polyurethane elastomer prepared in step 1 in an organic solvent, adding a certain amount of lithium bis(trifluoromethanesulfonyl)imide, and dispersing the mixture evenly; Step 3. Based on the conductive elastomer prepared in step 2, a certain amount of carboxylated multi-walled carbon nanotubes is uniformly dispersed in an organic solvent. After ultrasonication for 30 minutes, the nanotubes are added to the dispersion prepared in S2 and, after complete dispersion, a film is formed at room temperature to obtain a high-strength, room-temperature self-healing polyurethane ion conductive elastomer.

3. The method for preparing a high-strength self-repairing polyurethane ion elastomer according to claim 2, characterized in that: In step 1, the diisocyanate is selected from one or more of hexamethylene diisocyanate, isophorone diisocyanate, 4,4-diphenylmethane diisocyanate, and toluene diisocyanate; polytetrahydrofuran needs to be subjected to high-temperature dehydration, and the reaction temperature for generating the polyurethane prepolymer is 60-90° C., and the reaction time is 2-4 hours; the chain extender for the multi-hydrogen bond acceptor and donor is adipic acid dihydrazide, and the trifunctional polymer is 2-amino-2-methyl-1,3-propanediol.

4. The method for preparing a high-strength self-repairing polyurethane ion elastomer according to claim 3, characterized in that: The molar ratio of the chain extender of the multi-hydrogen bond acceptor and donor to polytetrahydrofuran in step 1 is 1:0.8-1.2, and the molar ratio of the multifunctional cross-linking agent in step 1 is 0.1-0.69 of the total amount.

5. The method for preparing a high-strength self-repairing polyurethane ion elastomer according to claim 2, characterized in that: The organic solvent in step 1 is selected from one or more of acetone, butanone, ether, toluene, xylene, tetrahydrofuran, ethylene glycol, N,N-dimethylformamide and N,N-dimethylacetamide.

6. The method for preparing a high-strength self-repairing polyurethane ion elastomer according to claim 2, characterized in that: The mass ratio of lithium bis(trifluoromethanesulfonyl)imide in step 2 is 10% to 30% of the mass of the added polyurethane elastomer.

7. The method for preparing a high-strength self-repairing polyurethane ion elastomer according to claim 2, characterized in that: The mass ratio of the carboxylated multi-walled carbon nanotubes in step 3 is 10% to 30% of the mass of the polyurethane elastomer.

8. A high-strength self-repairing polyurethane ion elastomer prepared according to the method of any one of claims 1 to 7.

9. Use of the high-strength self-healing polyurethane ion elastomer according to claim 8 in a flexible sensor.

10. Use of the high-strength self-healing polyurethane ion elastomer according to claim 8 in energy harvesting.

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