A self-repairing polyurethane material and its preparation method and application

Abstract

The present invention provides a self-repairing polyurethane material and a preparation method and application thereof. The raw materials for preparing the self-repairing polyurethane material include dimethylglyoxime, acrylic polyol, polyol matrix, aromatic isocyanate, chain extender and organic solvent; the mass percentage of organic solvent in the raw materials for preparing the self-repairing polyurethane material is 30%-70%. The self-repairing polyurethane grip leather made of the self-repairing polyurethane material provided in the present invention has astringent feeling and self-repairing function, and can be used to prepare automobile steering wheels.

Description

Technical Field

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

[0002] During the use of polyurethane synthetic leather, it is often worn or scratched, causing damage to the synthetic leather. Polyurethane synthetic leather is different from ordinary textile products such as cloth. After damage, it can be patched and then used again. Most polyurethane synthetic leathers face the situation of being discarded after damage. Generally, polyurethane synthetic leathers used in ordinary products, such as toys, slippers, leather shoes, leather clothes and other polyurethane synthetic leather products, are not distressed when they are discarded after damage, after all, they are relatively cheap fast-moving consumer goods. In some fields, the damage of polyurethane synthetic leather will make people feel distressed, such as the expensive grip leather field, especially the polyurethane grip leather used in car steering wheels. When the surface of the steering wheel is damaged after long-term use, most people will not discard the steering wheel, but continue to use it, but facing a damaged steering wheel every day affects the user's mood.

[0003] In recent years, some researchers have studied polyurethane materials with self-repairing properties. CN109252387A discloses a leather / synthetic leather based on self-repairing waterborne polyurethane and a preparation method thereof. The self-repairing waterborne polyurethane leather / synthetic leather uses a waterborne polyurethane with self-repairing function as a coating surface layer. The raw materials for synthesizing the polyurethane include: diols, internal crosslinking agents, isocyanates, disulfide bond-containing chain extenders, silane coupling agents, etc. The prepolymer method is used to synthesize a waterborne polyurethane emulsion with self-repairing function, and the leather / synthetic leather with self-repairing function is prepared according to the dry leather / synthetic leather transfer coating process. The leather / synthetic leather based on self-repairing waterborne polyurethane provided by the technical solution does not require any external additives, and the damaged coating can be self-repaired at a certain temperature. The required conditions are mild and the repair efficiency is high.

[0004] CN117447673A discloses a self-repairing polyurethane elastomer and a preparation method, the preparation method comprising the following steps: taking polytetrahydrofuran ether diol, adding isophorone diisocyanate and a catalyst under the protection of an inert gas, and reacting at 20-40°C for 1-3h; after the reaction, sequentially adding 2,6-pyridine dimethanol, 4,4'-dihydroxydiphenyl disulfide and a solvent, reacting at 70-90°C in an inert atmosphere for 2-5h, after the reaction, adding 4,4'-methylenebis(2-chloroaniline) and a solvent to continue reacting for 2-5h, and then removing the solvent. The self-repairing polyurethane elastomer provided by the technical solution has excellent self-repairing properties after being broken. After the broken polyurethane elastomer is repaired for a period of time at room temperature, its mechanical properties are restored to about 90%, showing an organic combination of high mechanical strength and good room temperature self-repairing ability.

[0005] CN117304443A discloses a polyurethane material with self-repairing function and its preparation method, wherein the polyurethane material with self-repairing function is formed by the reaction of -NCO-terminated prepolymer, N-(2-hydroxyethyl) maleimide and dibutyltin dilaurate; the -NCO-terminated prepolymer is formed by the reaction of modified isocyanate, polytetrahydrofuran ether glycol and dibutyltin dilaurate; the N-(2-hydroxyethyl) maleimide is formed by the reaction of DA powder, ethanol and ethanolamine to produce precipitation, and then reacting with xylene at high temperature reflux. The polyurethane material with self-repairing function provided by the technical solution can achieve self-repair after being damaged, which not only ensures the safety of the use of the polyurethane material, but also prolongs the service life of the polyurethane material, and at the same time can reduce the negative impact that the polyurethane material may have on the environment after being discarded, and has good ecological benefits.

[0006] The self-repairing synthetic leather technology provided by the prior art mainly uses disulfide bonds or N-(2-hydroxyethyl)maleimide. If it is prepared into polyurethane grip leather, it is easy to make the surface of the grip leather smooth and not astringent. When applied to the steering wheel, people's hands cannot hold the steering wheel tightly under sweating conditions, which may cause traffic accidents.

[0007] Therefore, it is necessary to develop a self-healing polyurethane material with astringent feeling. Summary of the invention

[0008] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a self-repairing polyurethane material and its preparation method and application. The self-repairing polyurethane grip leather made of the self-repairing polyurethane material has astringent feeling and self-repairing function, and can be used to prepare automobile steering wheels.

[0009] To achieve this object, the present invention adopts the following technical solutions:

[0010] In a first aspect, the present invention provides a self-healing polyurethane material, wherein the raw materials for preparing the self-healing polyurethane material include dimethylglyoxime, acrylic polyol, a polyol matrix, aromatic isocyanate, a chain extender and an organic solvent;

[0011] The mass percentage of the organic solvent in the raw materials for preparing the self-healing polyurethane material is 30%-70%, for example, 35%, 40%, 45%, 50%, 55%, 60% or 65%.

[0012] In the present invention, the self-repairing polyurethane material made of dimethylglyoxime, acrylic polyol, polyol matrix, aromatic isocyanate and chain extender can be used to prepare self-repairing polyurethane grip leather, and the leather surface has astringent feeling and self-repairing function. By introducing dimethylglyoxime into the self-repairing polyurethane material, the synthesized polyurethane resin contains thermally reversible oxime-carbamate bonds, allowing it to selectively self-heal when heated. The oxime-carbamate bonds can be rearranged at room temperature, so that hydrogen bonds and dynamic oxime-carbamate bonds can be effectively regenerated. Acrylic polyols are introduced into the self-repairing polyurethane material, so that when preparing synthetic leather, the epidermis is not too thick, in which case the surface of the synthetic leather is smooth, and not too thin, in which case the surface is skin-like and has no astringent feeling.

[0013] Preferably, the acrylic polyol includes any one of 2,3-dihydroxypropyl acrylate, 2-methyl-2-acrylate-2,3-dihydroxypropyl ester, or 5,6-dihydroxyhexyl methacrylate, or a combination of at least two thereof.

[0014] Preferably, the polyol matrix comprises a polymer polyol.

[0015] Preferably, the weight average molecular weight of the polymer polyol is 1000-4000, for example, 1300, 1600, 1900, 2200, 2500, 2800, 3100, 3400 or 3700.

[0016] Preferably, the polymer polyol includes any one of Asahikawa Chemical XCPP-10001, Asahikawa Chemical XCPP-10013, Asahikawa Chemical XCPP-20006, Asahikawa Chemical XCPP-20008, Asahikawa Chemical XCPP-30017, Asahikawa Chemical XCPP-30013 or Asahikawa Chemical XCPP-40013, or a combination of at least two thereof.

[0017] Preferably, the aromatic isocyanate includes any one of diphenylmethane diisocyanate (MDI) or toluene diisocyanate (TDI) or a combination of both.

[0018] Preferably, the chain extender includes any one of monoethanolamine, 1,4-butanediol, 2,2-dihydroxymethylpropionic acid or ethylene glycol, or a combination of at least two thereof.

[0019] Preferably, the organic solvent includes any one of N,N-dimethylacetamide, ethyl acetate, butanone, toluene or dimethyl carbonate, or a combination of at least two thereof.

[0020] Preferably, the molar ratio of dimethylglyoxime to the polyol matrix is ​​0.4-0.6:1, for example, 0.42:1, 0.44:1, 0.46:1, 0.48:1, 0.50:1, 0.52:1, 0.54:1, 0.56:1 or 0.58:1, etc.

[0021] Preferably, the molar ratio of the acrylic polyol to the polyol matrix is ​​1-2:1, for example, 1.1:1, 1.2:1, 1.3:1, 1.4:1, 1.5:1, 1.6:1, 1.7:1, 1.8:1 or 1.9:1, etc.

[0022] Preferably, the molar ratio of the aromatic isocyanate to the polyol matrix is ​​6-8:1, for example, 6.2:1, 6.4:1, 6.6:1, 6.8:1, 7.0:1, 7.2:1, 7.4:1, 7.6:1 or 7.8:1, etc.

[0023] Preferably, the molar ratio of the chain extender to the polyol matrix is ​​3.8-4.6:1, for example, 3.9:1, 4.0:1, 4.1:1, 4.2:1, 4.3:1, 4.4:1 or 4.5:1, etc.

[0024] In a second aspect, the present invention provides a method for preparing the self-healing polyurethane material as described in the first aspect, the preparation method comprising the following steps:

[0025] (1) mixing dimethylglyoxime, acrylic polyol, polyol matrix, aromatic isocyanate and organic solvent, and reacting them to obtain a prepolymer;

[0026] (2) The prepolymer prepared in step (1) and the chain extender are mixed and reacted to obtain the self-healing polyurethane material.

[0027] In the present invention, dimethylglyoxime, acrylic polyol, polyol matrix and aromatic isocyanate are reacted to form a prepolymer, and then a chain extender is added to form a hard segment to prepare the self-repairing polyurethane material.

[0028] Preferably, the reaction temperature in step (1) is 55-80°C (e.g., 58°C, 61°C, 64°C, 67°C, 70°C, 73°C, 76°C or 79°C, etc.), and the reaction time is 0.5-3h (e.g., 0.8h, 1.1h, 1.4h, 1.7h, 2.0h, 2.3h, 2.6h or 2.9h, etc.).

[0029] Preferably, the reaction temperature in step (2) is 65-85°C (e.g., 67°C, 69°C, 71°C, 73°C, 75°C, 77°C, 79°C, 81°C or 83°C, etc.), and the reaction time is 4-10h (e.g., 5h, 6h, 7h, 8h or 9h, etc.).

[0030] In the present invention, the method for determining when the reaction in step (2) is terminated is to use a glass rod to take a point of the product in the reaction system, and then drip hydrogen peroxide. If the product turns yellow, it means that the isocyanate in the product has not reacted completely and the reaction needs to continue. If the product is colorless after dripping hydrogen peroxide, the reaction is complete and the reaction can be terminated.

[0031] Preferably, the step (1) specifically comprises mixing dimethylglyoxime, acrylic polyol, a polyol matrix and an organic solvent, and then adding aromatic isocyanate to react to obtain a prepolymer.

[0032] In a third aspect, the present invention provides a self-repairing polyurethane grip leather, wherein the raw materials for preparing the self-repairing polyurethane grip leather include the self-repairing polyurethane material as described in the first aspect.

[0033] Preferably, the method for preparing the self-repairing polyurethane handle leather comprises the following steps: coating the self-repairing polyurethane material as described in the first aspect on the surface of release paper, placing it in an oven for drying, and obtaining the self-repairing polyurethane handle leather.

[0034] Preferably, the coating has a thickness of 1-3 mm, such as 1 mm, 1.5 mm, 2 mm, 2.3 mm, 2.6 mm or 3 mm.

[0035] Preferably, the drying temperature is 120-160°C, for example, 125°C, 130°C, 135°C, 140°C, 145°C, 150°C or 155°C, and the drying time is 20-40min, for example, 22min, 24min, 26min, 28min, 30min, 32min, 34min, 36min or 38min, etc.

[0036] Preferably, the self-repairing polyurethane grip leather is used to prepare automobile steering wheels.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] The self-repairing polyurethane material of the present invention is prepared by dimethylglyoxime, acrylic polyol, polyol matrix, aromatic isocyanate and chain extender. The self-repairing polyurethane grip leather made of the self-repairing polyurethane material has astringent feeling and self-repairing performance. The preparation method of the self-repairing polyurethane material and the self-repairing polyurethane grip leather of the present invention has simple process, low cost and energy consumption, excellent product performance, and good application prospect. DETAILED DESCRIPTION

[0039] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only used to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0040] Example 1

[0041] The present embodiment provides a self-repairing polyurethane material, a preparation method thereof, and a self-repairing polyurethane grip leather. The raw materials for preparing the self-repairing polyurethane material include the following components in molar proportions: 0.4 parts of dimethylglyoxime, 2 parts of acrylic polyol (2,3-dihydroxypropyl acrylate), 1 part of a polyol matrix (Asahikawa Chemical XCPP-10013, with a weight average molecular weight of 1000, sourced from Asahikawa Chemical (Suzhou) Co., Ltd.), 6 parts of aromatic isocyanate (diphenylmethane diisocyanate), 3.8 parts of a chain extender (ethylene glycol), and an organic solvent (N,N-dimethylacetamide).

[0042] The mass percentage of organic solvent in the raw materials for preparing the self-repairing polyurethane material is 30%.

[0043] The preparation method of the self-repairing polyurethane material comprises the following steps:

[0044] (1) adding dimethylglyoxime, acrylic polyol, and polyol matrix to an organic solvent, stirring for 30 minutes to mix, and then adding aromatic isocyanate to react at a temperature of 55° C. for 0.5 hours to obtain a prepolymer;

[0045] (2) The prepolymer prepared in step (1) and the chain extender are mixed and reacted at a temperature of 60° C. for a reaction time of 4 hours. After the reaction time is reached, a glass rod is used to take a point of the product in the system, and then hydrogen peroxide is dripped on it. The product to be measured is colorless, and the reaction is completed to obtain the self-healing polyurethane material.

[0046] A self-repairing polyurethane grip leather. The preparation method of the self-repairing polyurethane grip leather is as follows: coating the self-repairing polyurethane material on the surface of release paper with a coating thickness of 1 mm, placing it in a 120° C. oven for drying for 20 minutes to obtain the self-repairing polyurethane grip leather.

[0047] Example 2

[0048] The present embodiment provides a self-repairing polyurethane material, a preparation method thereof, and a self-repairing polyurethane grip leather. The raw materials for preparing the self-repairing polyurethane material include the following components in molar proportions: 0.6 parts of dimethylglyoxime, 1 part of acrylic polyol (2-methyl-2-acrylic acid-2,3-dihydroxypropyl ester), 1 part of a polyol matrix (Asahikawa Chemical XCPP-20006, with a weight average molecular weight of 2000, sourced from Asahikawa Chemical (Suzhou) Co., Ltd.), 7 parts of aromatic isocyanate (diphenylmethane diisocyanate), 4.6 parts of a chain extender (1,4-butanediol), and an organic solvent (ethyl acetate).

[0049] The mass percentage of the organic solvent in the raw materials for preparing the self-repairing polyurethane material is 50%.

[0050] The preparation method of the self-repairing polyurethane material comprises the following steps:

[0051] (1) adding dimethylglyoxime, acrylic polyol, and polyol matrix to an organic solvent, stirring for 30 minutes to mix, and then adding aromatic isocyanate to react at a temperature of 65° C. for 2 hours to obtain a prepolymer;

[0052] (2) The prepolymer prepared in step (1) and the chain extender are mixed and reacted at a temperature of 70° C. for a reaction time of 8 h. After the reaction time is reached, a point of the product in the system is taken with a glass rod, and then hydrogen peroxide is dripped on it. The product to be tested is colorless, and the reaction is completed to obtain the self-healing polyurethane material.

[0053] A self-repairing polyurethane grip leather. The preparation method of the self-repairing polyurethane grip leather is as follows: coating the self-repairing polyurethane material on the surface of release paper with a coating thickness of 2 mm, placing it in a 140° C. oven for drying for 30 minutes to obtain the self-repairing polyurethane grip leather.

[0054] Example 3

[0055] The present embodiment provides a self-repairing polyurethane material, a preparation method thereof, and a self-repairing polyurethane grip leather. The raw materials for preparing the self-repairing polyurethane material include the following components in molar proportions: 0.5 parts of dimethylglyoxime, 1.5 parts of acrylic polyol (5,6-dihydroxyhexyl methacrylate), 1 part of a polyol matrix (Asahikawa Chemical XCPP-40013 polytetramethylene ether diol, with a weight average molecular weight of 4000, sourced from Asahikawa Chemical (Suzhou) Co., Ltd.), 8 parts of aromatic isocyanate (toluene diisocyanate), 4.2 parts of a chain extender (monoethanolamine), and an organic solvent (butanone).

[0056] The mass percentage of organic solvent in the raw materials for preparing the self-repairing polyurethane material is 70%.

[0057] The preparation method of the self-repairing polyurethane material comprises the following steps:

[0058] (1) adding dimethylglyoxime, acrylic polyol, and polyol matrix to an organic solvent, stirring for 30 minutes to mix, and then adding aromatic isocyanate to react at a temperature of 80° C. for 3 hours to obtain a prepolymer;

[0059] (2) Mixing the prepolymer prepared in step (1) and the chain extender, and reacting them at a temperature of 85° C. for 10 h. After the reaction time is up, taking a little product in the system with a glass rod, and then dripping hydrogen peroxide on it. The product to be tested is colorless, and the reaction is completed to obtain the self-healing polyurethane material.

[0060] A self-repairing polyurethane grip leather. The preparation method of the self-repairing polyurethane grip leather is as follows: coating the self-repairing polyurethane material on the surface of release paper with a coating thickness of 3 mm, placing it in a 160° C. oven for drying for 40 minutes to obtain the self-repairing polyurethane grip leather.

[0061] Example 4

[0062] This embodiment provides a self-repairing polyurethane material and a preparation method thereof and a self-repairing polyurethane grip leather, which is different from Example 1 only in that the molar amount of dimethylglyoxime is adjusted to 0.3 parts, and the rest is the same as Example 1.

[0063] Example 5

[0064] This embodiment provides a self-repairing polyurethane material and a preparation method thereof and a self-repairing polyurethane grip leather, which is different from Example 1 only in that the molar amount of dimethylglyoxime is adjusted to 0.7 parts, and the rest is the same as Example 1.

[0065] Example 6

[0066] This embodiment provides a self-repairing polyurethane material and a preparation method thereof and a self-repairing polyurethane grip leather. The only difference between this embodiment and Example 1 is that the molar amount of acrylic polyol (2,3-dihydroxypropyl acrylate) is adjusted to 0.5 parts, and the rest is the same as Example 1.

[0067] Example 7

[0068] This embodiment provides a self-repairing polyurethane material and a preparation method thereof and a self-repairing polyurethane grip leather. The only difference between this embodiment and Example 1 is that the molar amount of acrylic polyol (2,3-dihydroxypropyl acrylate) is adjusted to 2.5 parts, and the rest is the same as Example 1.

[0069] Comparative Example 1

[0070] This comparative example provides a polyurethane material, a preparation method thereof, and a polyurethane grip leather, which differs from Example 1 only in that dimethylglyoxime is replaced with an equal molar amount of a polyol matrix (Asahikawa Chemical XCPP-10013, with a weight average molecular weight of 1000, sourced from Asahikawa Chemical (Suzhou) Co., Ltd.), and the rest is the same as Example 1.

[0071] Comparative Example 2

[0072] This comparative example provides a self-repairing polyurethane material, a preparation method thereof, and a self-repairing polyurethane grip leather, which differs from Example 1 only in that the acrylic polyol (2,3-dihydroxypropyl acrylate) is replaced with an equal molar amount of a polyol matrix (Asahikawa Chemical XCPP-10013, with a weight average molecular weight of 1000, sourced from Asahikawa Chemical (Suzhou) Co., Ltd.), and the rest is the same as Example 1.

[0073] Comparative Example 3

[0074] This comparative example provides a polyurethane material and a preparation method thereof and a polyurethane grip leather, which differs from Example 1 only in that the aromatic isocyanate (diphenylmethane diisocyanate) is replaced with the same molar amount of isophorone diisocyanate, and the rest is the same as Example 1.

[0075] Comparative Example 4

[0076] This comparative example provides a polyurethane material, a preparation method thereof, and a polyurethane grip leather. The only difference between this comparative example and Example 1 is that the mass percentage of the organic solvent in the raw material for preparing the polyurethane material is adjusted to 20%, and the rest is the same as Example 1.

[0077] The following performance tests were performed on the self-repairing polyurethane handle leather provided in the example and the polyurethane handle leather provided in the comparative example.

[0078] (1) Test for roughness: Move your fingers across the surface of the synthetic leather. The roughness is classified into three levels: excellent roughness, good roughness, and poor roughness, based on the degree of difficulty in sliding the fingers.

[0079] (2) Self-repairing performance: Use a blade to make obvious surface scratches on the surface of the self-repairing polyurethane grip leather or polyurethane grip leather. Then, after leaving it at room temperature for 12 hours, observe the scratch condition after 12 hours. The quality of its self-repairing performance can be judged by whether the scratch can be restored.

[0080] The test results are shown in Table 1.

[0081] Table 1

[0082]

[0083]

[0084] According to the test results in Table 1, the self-repairing polyurethane grip leather made of the self-repairing polyurethane material of the present invention has good astringency and self-repairing function.

[0085] Compared with Example 1, if the molar ratio of dimethylglyoxime and the polyol matrix is ​​too large (Example 5), the self-healing performance of the self-healing polyurethane grip leather will be affected. It can be seen that the self-healing polyurethane material with a molar ratio of dimethylglyoxime and the polyol matrix in the range of 0.4-0.6:1 has better performance.

[0086] Compared with Example 1, if the molar ratio of acrylic polyol and polyol matrix is ​​too small (Example 6) or too large (Example 7), the self-repairing performance and astringency of the self-repairing polyurethane grip leather will be affected. It can be seen that the self-repairing polyurethane material with a molar ratio of acrylic polyol and polyol matrix in the range of 1-2:1 has better performance.

[0087] Compared with Example 1, if dimethylglyoxime is not added (Comparative Example 1), the obtained polyurethane grip leather does not have astringent feeling and self-repairing performance.

[0088] Compared with Example 1, if acrylic polyol is not added (Comparative Example 2), the self-repairing polyurethane grip leather obtained does not have astringent feeling.

[0089] Compared with Example 1, if the aromatic isocyanate (diphenylmethane diisocyanate) is replaced with the same molar amount of isophorone diisocyanate (Comparative Example 3), the obtained polyurethane grip leather has a poor astringency and does not have self-repairing properties. This is because the activity of isophorone diisocyanate is significantly lower than that of aromatic isocyanate, the reaction is difficult, the molecular weight of the obtained polyurethane material is small, the toughness of the formed polyurethane grip leather is poor, and the degree of damage to the leather sample is much greater than that of the leather sample in Example 1, and the damage is irreversible.

[0090] Compared with Example 1, if the mass percentage of organic solvent in the preparation raw materials of the polyurethane material is too low (Comparative Example 4), the obtained polyurethane grip leather has poor astringency and poor self-repairing performance. This is because the organic solvent content is low, the molecular weight of the obtained polyurethane material is small, the formed polyurethane grip leather has poor toughness, the degree of damage to the leather sample is much greater than that of the leather sample in Example 1, and the damage is irreversible.

[0091] The applicant declares that the present invention uses the above-mentioned embodiments to illustrate a self-healing polyurethane material and its preparation method and application, but the present invention is not limited to the above-mentioned embodiments, that is, it does not mean that the present invention must rely on the above-mentioned embodiments to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of various raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A self-repairing polyurethane material, characterized in that: The raw materials for preparing the self-repairing polyurethane material include dimethylglyoxime, acrylic polyol, polyol matrix, aromatic isocyanate, chain extender and organic solvent; The mass percentage of organic solvent in the raw materials for preparing the self-repairing polyurethane material is 30%-70%; The molar ratio of dimethylglyoxime to the polyol matrix is ​​0.4-0.6:1; The molar ratio of the acrylic polyol to the polyol matrix is ​​1-2:1; The acrylic polyol includes any one or a combination of at least two of 2,3-dihydroxypropyl acrylate, 2-methyl-2-acrylate-2,3-dihydroxypropyl ester or 5,6-dihydroxyhexyl methacrylate; The polyol matrix includes a polymer polyol; The chain extender includes any one of monoethanolamine, 1,4-butanediol, 2,2-dihydroxymethylpropionic acid or ethylene glycol, or a combination of at least two of them.

2. The self-repairing polyurethane material according to claim 1, characterized in that: The weight average molecular weight of the polymer polyol is 1000-4000.

3. The self-repairing polyurethane material according to claim 1, characterized in that: The aromatic isocyanate includes any one of diphenylmethane diisocyanate and toluene diisocyanate or a combination of at least two thereof.

4. The self-repairing polyurethane material according to claim 1, characterized in that: The organic solvent includes any one of N,N-dimethylacetamide, ethyl acetate, butanone, toluene or dimethyl carbonate, or a combination of at least two thereof.

5. The self-repairing polyurethane material according to claim 1, characterized in that: The molar ratio of the aromatic isocyanate to the polyol matrix is ​​6-8:

1.

6. The self-repairing polyurethane material according to claim 1, characterized in that: The molar ratio of the chain extender to the polyol matrix is ​​3.8-4.6:

1.

7. A method for preparing the self-repairing polyurethane material according to any one of claims 1 to 6, characterized in that: The preparation method comprises the following steps: (1) dimethylglyoxime, acrylic polyol, polyol matrix, aromatic isocyanate and organic solvent are mixed and reacted to obtain a prepolymer; (2) The prepolymer prepared in step (1) and the chain extender are mixed and reacted to obtain the self-healing polyurethane material.

8. The preparation method according to claim 7, characterized in that: The reaction temperature in step (1) is 55-80°C and the reaction time is 0.5-3 h; The reaction temperature in step (2) is 65-85°C and the reaction time is 4-10 h.

9. A self-repairing polyurethane grip leather, characterized in that: The raw materials for preparing the self-repairing polyurethane grip leather include the self-repairing polyurethane material as described in any one of claims 1-6.

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