A self-healing polyurethane elastomer material with carbon dioxide as its basic characteristic and its preparation method

Abstract

This invention relates to a carbon dioxide-based self-healing polyurethane elastomer material and its preparation method, belonging to the field of polymer materials technology. The polyurethane elastomer material comprises, by weight, 180-220g of carbon dioxide-based diol, 60-80g of isocyanate, 8-12g of chain extender, 1-3g of crosslinking agent, and 0.06-0.1g of catalyst. This invention introduces a dynamic oxime crosslinking network, enabling the polyurethane elastomer to automatically heal cracks at room temperature or under mild heating conditions. After cutting, the material can be simply butt-jointed and placed at room temperature or under heating conditions for several minutes to several hours to recover most of its mechanical strength. The polyurethane elastomer of this invention combines the advantages of a dynamic crosslinking network and a microphase separation structure, exhibiting excellent mechanical strength and toughness. The presence of dynamic oxime bonds and hydrogen bonds not only endows it with self-healing ability but also improves the material's cohesive strength and tear resistance. Compared with traditional self-healing polyurethanes, the material of this invention can achieve higher tensile strength and elongation at break.

Description

Technical Field

[0001] This invention belongs to the field of polymer materials technology, specifically relating to a carbon dioxide-based self-healing polyurethane elastomer material and its preparation method. Background Technology

[0002] Polyurethane elastomers have been widely used in rubber, coatings, adhesives, biomedicine and other fields due to their excellent mechanical properties and processability.

[0003] However, traditional polyurethane materials inevitably develop cracks, scratches, and other damage during long-term use, leading to performance degradation or even failure. To address this issue, self-healing polymer materials have become a research hotspot in recent years. Self-healing materials introduce reversible chemical bonds or interactions within the material, enabling it to automatically heal when damaged, thereby extending its service life and improving reliability.

[0004] Currently, methods for achieving self-healing in polyurethane mainly fall into two categories: exogenous and endogenous. Exogenous self-healing typically involves introducing microcapsules or fiber tubes into the polyurethane matrix to encapsulate a repair agent. When the material is damaged, the repair agent is released and polymerizes to fill the cracks. This method has limited repair efficiency, and the repair agent cannot be regenerated after consumption. Summary of the Invention

[0005] The purpose of this invention is to provide a carbon dioxide-based self-healing polyurethane elastomer material and its preparation method in order to solve the above-mentioned problems.

[0006] The present invention achieves the above objectives through the following technical solutions: This invention provides a carbon dioxide-based self-healing polyurethane elastomer material, which comprises, by weight: 180-220g carbon dioxide-based diol, 60-80g isocyanate, 8-12g chain extender, 1-3g crosslinking agent, and 0.06-0.1g catalyst.

[0007] As a further optimization of the present invention, the number average molecular weight of the carbon dioxide-based diol is 1000-3000 g / mol, and the carbon dioxide insertion rate in the carbon dioxide-based diol is 5-40% (mass fraction); the carbon dioxide-based diol segments contain polycarbonate and polyether structures.

[0008] As a further optimization of the present invention, the isocyanate is selected from one or more of 4,4'-diphenylmethane diisocyanate, toluene diisocyanate, hexamethylene diisocyanate and isophorone diisocyanate.

[0009] As a further optimization of the present invention, the chain extender is selected from one or more of 1,4-butanediol, ethylene glycol, diethylene glycol, hexanediol, ethylenediamine, and butanediamine.

[0010] As a further optimization of the present invention, the crosslinking agent is selected from one or more of dimethylglyoxime, cyclohexanedione dioxime, and p-benzoquinone dioxime.

[0011] As a further optimization of the present invention, the catalyst is selected as dibutyltin dilaurate.

[0012] This invention also provides a method for preparing a carbon dioxide-based self-healing polyurethane elastomer material, comprising the following steps: a. Preparation of prepolymer: Carbon dioxide-based diol is added to a dry four-necked flask and vacuum dehydrated at 60-120℃ and a vacuum degree of -0.08~-0.1MPa for 1-2 hours. After dehydration, nitrogen gas is introduced to cool the temperature to 40-60℃. Isocyanate is added and catalyst is added dropwise at a rate of 1-2 drops / second. The reaction is carried out at 50-90℃ for 0.5-2 hours to obtain isocyanate-terminated polyurethane prepolymer. b. Chain extension and crosslinking: The polyurethane prepolymer is cooled to 70°C, and a chain extender and a crosslinking agent are added. The reaction is carried out at 70°C for 0.5-2 hours to extend the chain and crosslink the polymer. The crosslinking agent reacts with the isocyanate groups at the end of the polyurethane prepolymer to form oxime carbamate bonds, thereby constructing a dynamic crosslinking network and obtaining the reactants. c. Cure the reactants in an oven at 80-120℃ for 12-18 hours. After curing, remove the sample and cool it to room temperature to obtain polyurethane elastomer material.

[0013] As a further optimization of the present invention, the molar ratio of isocyanate groups to hydroxyl groups is 1.0-1.5:1; the molar ratio of chain extender to carbon dioxide diol is 0.2-0.8:1; and the molar ratio of oxime groups to the terminal -NCO of polyurethane prepolymer in the crosslinking agent is 0.05-0.3:1.

[0014] The beneficial effects of this invention are as follows: Excellent self-healing properties: By introducing a dynamic oxime crosslinking network, this invention enables polyurethane elastomers to automatically heal cracks at room temperature or under mild heating conditions. After the material is cut, it can be simply butt-jointed and placed at room temperature for several minutes to several hours to restore most of its mechanical strength, which significantly extends the service life of the material and reduces maintenance and replacement costs. Excellent mechanical properties: The polyurethane elastomer of the present invention combines the advantages of dynamic cross-linked network and microphase separation structure, and has excellent mechanical strength and toughness. The presence of dynamic oxime bonds and hydrogen bonds not only endows it with self-healing ability, but also improves the cohesive strength and tear resistance of the material. Compared with traditional self-healing polyurethane, the material of the present invention can achieve higher tensile strength and elongation at break. Detailed Implementation

[0015] The present application will now be described in further detail. It should be noted that the following specific embodiments are only used to further illustrate the present application and should not be construed as limiting the scope of protection of the present application. Those skilled in the art can make some non-essential improvements and adjustments to the present application based on the above application content.

[0016] Unless otherwise specified, all methods used in this invention are conventional methods known to those skilled in the art, and all reagents and materials used are commercially available products.

[0017] Example 1

[0018] The number-average molecular weight of the carbon dioxide-based glycol is 2000 g / mol, and the carbon dioxide insertion rate in the carbon dioxide-based glycol is 30% (mass fraction); the carbon dioxide-based glycol segments contain polycarbonate and polyether structures. Prepolymer preparation: 200g of carbon dioxide-based diol was added to a dry four-necked flask and vacuum dehydrated for 1h at 100℃ and -0.08MPa. After the dehydration was completed, nitrogen gas was introduced to cool the temperature to 60℃. 70g of 4,4'-diphenylmethane diisocyanate was added and 0.08g of dibutyltin dilaurate was added dropwise at a rate of 1 drop / second. The reaction was carried out at 80℃ for 2h to obtain an isocyanate-terminated polyurethane prepolymer. Chain extension and crosslinking: The polyurethane prepolymer was cooled to 70°C, and 10g of 1,4-butanediol and 2g of dimethylglyoxime were added. The reaction was carried out at 70°C for 1 hour to extend the chain and crosslink the polymer. The crosslinking agent reacted with the isocyanate groups at the end of the polyurethane prepolymer to form oxime carbamate bonds, thereby constructing a dynamic crosslinking network and obtaining the reactants. The reactants were cured in an oven at 80°C for 12 hours. After curing, the samples were removed and cooled to room temperature to obtain polyurethane elastomer materials. The molar ratio of isocyanate groups to hydroxyl groups is 1.0:1; the molar ratio of chain extender to carbon dioxide diol is 0.6:1; and the molar ratio of oxime groups to the terminal -NCO of polyurethane prepolymer in the crosslinking agent is 0.2:1.

[0019] Example 2

[0020] The number-average molecular weight of the carbon dioxide-based glycol is 2000 g / mol, and the carbon dioxide insertion rate (mass fraction) in the carbon dioxide-based glycol is 30%; the carbon dioxide-based glycol segments contain polycarbonate and polyether structures. Prepolymer preparation: 200g of carbon dioxide-based diol was added to a dry four-necked flask and vacuum dehydrated for 1h at 100℃ and a vacuum degree of -0.08MPa. After the dehydration was completed, nitrogen gas was introduced to cool the temperature to 60℃. 70g of toluene diisocyanate was added and 0.08g of dibutyltin dilaurate was added dropwise at a rate of 1 drop / second. The reaction was carried out at 80℃ for 2h to obtain an isocyanate-terminated polyurethane prepolymer. Chain extension and crosslinking: The polyurethane prepolymer was cooled to 70°C, and 10g of 1,4-butanediol and 2g of dimethylglyoxime were added. The reaction was carried out at 70°C for 1 hour to extend the chain and crosslink the polymer. The crosslinking agent reacted with the isocyanate groups at the end of the polyurethane prepolymer to form oxime carbamate bonds, thus constructing a dynamic crosslinking network and obtaining the reactants. The reactants were cured in an oven at 80°C for 12 hours. After curing, the samples were removed and cooled to room temperature to obtain polyurethane elastomer materials. The molar ratio of isocyanate groups to hydroxyl groups is 1.0:1; the molar ratio of chain extender to carbon dioxide diol is 0.6:1; and the molar ratio of oxime groups to the terminal -NCO of polyurethane prepolymer in the crosslinking agent is 0.2:1.

[0021] Example 3

[0022] The number-average molecular weight of the carbon dioxide-based glycol is 2000 g / mol, and the carbon dioxide insertion rate in the carbon dioxide-based glycol is 30% (mass fraction); the carbon dioxide-based glycol segments contain polycarbonate and polyether structures. Prepolymer preparation: 200g of carbon dioxide-based diol was added to a dry four-necked flask and vacuum dehydrated for 1h at 100℃ and a vacuum degree of -0.08MPa. After the dehydration was completed, nitrogen gas was introduced to cool the temperature to 60℃. 70g of hexamethylene diisocyanate was added and 0.08g of dibutyltin dilaurate was added dropwise at a rate of 1 drop / second. The reaction was carried out at 80℃ for 2h to obtain an isocyanate-terminated polyurethane prepolymer. Chain extension and crosslinking: The polyurethane prepolymer was cooled to 70°C, and 10g of ethylene glycol and 2g of butanedione oxime were added. The reaction was carried out at 70°C for 1 hour to extend the chain and crosslink the polymer. The crosslinking agent reacted with the isocyanate groups at the end of the polyurethane prepolymer to form oxime carbamate bonds, thus constructing a dynamic crosslinking network and obtaining the reactants. The reactants were cured in an oven at 80°C for 12 hours. After curing, the samples were removed and cooled to room temperature to obtain polyurethane elastomer materials. The molar ratio of isocyanate groups to hydroxyl groups is 1.0:1; the molar ratio of chain extender to carbon dioxide diol is 0.6:1; and the molar ratio of oxime groups to the terminal -NCO of polyurethane prepolymer in the crosslinking agent is 0.2:1.

[0023] Example 4

[0024] The number-average molecular weight of the carbon dioxide-based glycol is 2000 g / mol, and the carbon dioxide insertion rate in the carbon dioxide-based glycol is 30% (mass fraction); the carbon dioxide-based glycol segments contain polycarbonate and polyether structures. Prepolymer preparation: 200g of carbon dioxide-based diol was added to a dry four-necked flask and vacuum dehydrated for 1h at 100℃ and -0.08MPa. After the dehydration was completed, nitrogen gas was introduced to cool the temperature to 60℃. 70g of 4,4'-diphenylmethane diisocyanate was added and 0.08g of dibutyltin dilaurate was added dropwise at a rate of 1 drop / second. The reaction was carried out at 80℃ for 2h to obtain an isocyanate-terminated polyurethane prepolymer. Chain extension and crosslinking: The polyurethane prepolymer was cooled to 70°C, and 10g of diethylene glycol and 2g of butanedione oxime were added. The reaction was carried out at 70°C for 1 hour to extend the chain and crosslink the polymer. The crosslinking agent reacted with the isocyanate groups at the end of the polyurethane prepolymer to form oxime carbamate bonds, thus constructing a dynamic crosslinking network and obtaining the reactants. The reactants were cured in an oven at 80°C for 12 hours. After curing, the samples were removed and cooled to room temperature to obtain polyurethane elastomer materials. The molar ratio of isocyanate groups to hydroxyl groups is 1.0:1; the molar ratio of chain extender to carbon dioxide diol is 0.6:1; and the molar ratio of oxime groups to the terminal -NCO of polyurethane prepolymer in the crosslinking agent is 0.2:1.

[0025] Example 5

[0026] The number-average molecular weight of the carbon dioxide-based glycol is 2000 g / mol, and the carbon dioxide insertion rate in the carbon dioxide-based glycol is 30% (mass fraction); the carbon dioxide-based glycol segments contain polycarbonate and polyether structures. Prepolymer preparation: 200g of carbon dioxide-based diol was added to a dry four-necked flask and vacuum dehydrated for 1h at 100℃ and -0.08MPa. After the dehydration was completed, nitrogen gas was introduced to cool the temperature to 60℃. 70g of 4,4'-diphenylmethane diisocyanate was added and 0.08g of dibutyltin dilaurate was added dropwise at a rate of 1 drop / second. The reaction was carried out at 80℃ for 2h to obtain an isocyanate-terminated polyurethane prepolymer. Chain extension and crosslinking: The polyurethane prepolymer was cooled to 70°C, and 10g hexanediol and 2g butanedione oxime were added. The reaction was carried out at 70°C for 1 hour to extend the chain and crosslink the polymer. The crosslinking agent reacted with the isocyanate groups at the end of the polyurethane prepolymer to form oxime carbamate bonds, thus constructing a dynamic crosslinking network and obtaining the reactants. The reactants were cured in an oven at 80°C for 12 hours. After curing, the samples were removed and cooled to room temperature to obtain polyurethane elastomer materials. The molar ratio of isocyanate groups to hydroxyl groups is 1.0:1; the molar ratio of chain extender to carbon dioxide diol is 0.6:1; and the molar ratio of oxime groups to the terminal -NCO of polyurethane prepolymer in the crosslinking agent is 0.2:1.

[0027] Example 6

[0028] The number-average molecular weight of the carbon dioxide-based glycol is 2000 g / mol, and the carbon dioxide insertion rate in the carbon dioxide-based glycol is 30% (mass fraction); the carbon dioxide-based glycol segments contain polycarbonate and polyether structures. Prepolymer preparation: 200g of carbon dioxide-based diol was added to a dry four-necked flask and vacuum dehydrated for 1h at 100℃ and -0.08MPa. After the dehydration was completed, nitrogen gas was introduced to cool the temperature to 60℃. 70g of 4,4'-diphenylmethane diisocyanate was added and 0.08g of dibutyltin dilaurate was added dropwise at a rate of 1 drop / second. The reaction was carried out at 80℃ for 2h to obtain an isocyanate-terminated polyurethane prepolymer. Chain extension and crosslinking: The polyurethane prepolymer was cooled to 70°C, and 10g of ethylenediamine and 2g of butanedione oxime were added. The reaction was carried out at 70°C for 1 hour to extend the chain and crosslink the polymer. The crosslinking agent reacted with the isocyanate groups at the end of the polyurethane prepolymer to form oxime carbamate bonds, thus constructing a dynamic crosslinking network and obtaining the reactants. The reactants were cured in an oven at 80°C for 12 hours. After curing, the samples were removed and cooled to room temperature to obtain polyurethane elastomer materials. The molar ratio of isocyanate groups to hydroxyl groups is 1.0:1; the molar ratio of chain extender to carbon dioxide diol is 0.6:1; and the molar ratio of oxime groups to the terminal -NCO of polyurethane prepolymer in the crosslinking agent is 0.2:1.

[0029] Example 7

[0030] The number-average molecular weight of the carbon dioxide-based glycol is 2000 g / mol, and the carbon dioxide insertion rate in the carbon dioxide-based glycol is 30% (mass fraction); the carbon dioxide-based glycol segments contain polycarbonate and polyether structures. Prepolymer preparation: 200g of carbon dioxide-based diol was added to a dry four-necked flask and vacuum dehydrated for 1h at 100℃ and -0.08MPa. After the dehydration was completed, nitrogen gas was introduced to cool the temperature to 60℃. 70g of 4,4'-diphenylmethane diisocyanate was added and 0.08g of dibutyltin dilaurate was added dropwise at a rate of 1 drop / second. The reaction was carried out at 80℃ for 2h to obtain an isocyanate-terminated polyurethane prepolymer. Chain extension and crosslinking: The polyurethane prepolymer was cooled to 70°C, and 10g of butanediamine and 2g of butanedione oxime were added. The reaction was carried out at 70°C for 1 hour to extend the chain and crosslink the polymer. The crosslinking agent reacted with the isocyanate groups at the end of the polyurethane prepolymer to form oxime carbamate bonds, thus constructing a dynamic crosslinking network and obtaining the reactants. The reactants were cured in an oven at 80°C for 12 hours. After curing, the samples were removed and cooled to room temperature to obtain polyurethane elastomer materials. The molar ratio of isocyanate groups to hydroxyl groups is 1.0:1; the molar ratio of chain extender to carbon dioxide diol is 0.6:1; and the molar ratio of oxime groups to the terminal -NCO of polyurethane prepolymer in the crosslinking agent is 0.2:1.

[0031] Example 8

[0032] The number-average molecular weight of the carbon dioxide-based glycol is 2000 g / mol, and the carbon dioxide insertion rate in the carbon dioxide-based glycol is 30% (mass fraction); the carbon dioxide-based glycol segments contain polycarbonate and polyether structures. Prepolymer preparation: 200g of carbon dioxide-based diol was added to a dry four-necked flask and vacuum dehydrated for 1h at 100℃ and -0.08MPa. After the dehydration was completed, nitrogen gas was introduced to cool the temperature to 60℃. 70g of 4,4'-diphenylmethane diisocyanate was added and 0.08g of dibutyltin dilaurate was added dropwise at a rate of 1 drop / second. The reaction was carried out at 80℃ for 2h to obtain an isocyanate-terminated polyurethane prepolymer. Chain extension and crosslinking: The polyurethane prepolymer was cooled to 70°C, and 10g of 1,4-butanediol and 2g of cyclohexanedione dioxime were added. The reaction was carried out at 70°C for 1 hour to extend the chain and crosslink the polymer. The crosslinking agent reacted with the isocyanate groups at the end of the polyurethane prepolymer to form oxime carbamate bonds, thus constructing a dynamic crosslinking network and obtaining the reactants. The reactants were cured in an oven at 80°C for 12 hours. After curing, the samples were removed and cooled to room temperature to obtain polyurethane elastomer materials. The molar ratio of isocyanate groups to hydroxyl groups is 1.0:1; the molar ratio of chain extender to carbon dioxide diol is 0.6:1; and the molar ratio of oxime groups to the terminal -NCO of polyurethane prepolymer in the crosslinking agent is 0.2:1.

[0033] Example 9

[0034] The number-average molecular weight of the carbon dioxide-based glycol is 2000 g / mol, and the carbon dioxide insertion rate in the carbon dioxide-based glycol is 30% (mass fraction); the carbon dioxide-based glycol segments contain polycarbonate and polyether structures. Prepolymer preparation: 200g of carbon dioxide-based diol was added to a dry four-necked flask and vacuum dehydrated for 1h at 100℃ and -0.08MPa. After the dehydration was completed, nitrogen gas was introduced to cool the temperature to 60℃. 70g of 4,4'-diphenylmethane diisocyanate was added and 0.08g of dibutyltin dilaurate was added dropwise at a rate of 1 drop / second. The reaction was carried out at 80℃ for 2h to obtain an isocyanate-terminated polyurethane prepolymer. Chain extension and crosslinking: The polyurethane prepolymer was cooled to 70°C, and 10g of 1,4-butanediol and 2g of p-benzoquinone dioxime were added. The reaction was carried out at 70°C for 1 hour to extend the chain and crosslink the polymer. The crosslinking agent reacted with the isocyanate groups at the end of the polyurethane prepolymer to form oxime carbamate bonds, thus constructing a dynamic crosslinking network and obtaining the reactants. The reactants were cured in an oven at 80°C for 12 hours. After curing, the samples were removed and cooled to room temperature to obtain polyurethane elastomer materials. The molar ratio of isocyanate groups to hydroxyl groups is 1.0:1; the molar ratio of chain extender to carbon dioxide diol is 0.6:1; and the molar ratio of oxime groups to the terminal -NCO of polyurethane prepolymer in the crosslinking agent is 0.2:1.

[0035] Example 10

[0036] The number-average molecular weight of the carbon dioxide-based glycol is 2000 g / mol, and the carbon dioxide insertion rate in the carbon dioxide-based glycol is 30% (mass fraction); the carbon dioxide-based glycol segments contain polycarbonate and polyether structures. Prepolymer preparation: 200g of carbon dioxide-based diol was added to a dry four-necked flask and vacuum dehydrated for 1h at 100℃ and a vacuum degree of -0.08MPa. After the dehydration was completed, nitrogen gas was introduced to cool the temperature to 60℃. 65g of isophorone diisocyanate was added and 0.08g of dibutyltin dilaurate was added dropwise at a rate of 1 drop / second. The reaction was carried out at 80℃ for 2h to obtain an isocyanate-terminated polyurethane prepolymer. Chain extension and crosslinking: The polyurethane prepolymer was cooled to 70°C, and 8g of 1,4-butanediol and 3g of dimethylglyoxime were added. The reaction was carried out at 70°C for 1 hour to extend the chain and crosslink the polymer. The crosslinking agent reacted with the isocyanate groups at the end of the polyurethane prepolymer to form oxime carbamate bonds, thereby constructing a dynamic crosslinking network and obtaining the reactants. The reactants were cured in an oven at 100°C for 8 hours. After curing, the samples were removed and cooled to room temperature to obtain polyurethane elastomer materials. The molar ratio of isocyanate groups to hydroxyl groups is 1.0:1; the molar ratio of chain extender to carbon dioxide diol is 0.6:1; and the molar ratio of oxime groups to the terminal -NCO of polyurethane prepolymer in the crosslinking agent is 0.2:1.

[0037] Example 11

[0038] The number-average molecular weight of the carbon dioxide-based glycol is 2000 g / mol, and the carbon dioxide insertion rate in the carbon dioxide-based glycol is 30% (mass fraction); the carbon dioxide-based glycol segments contain polycarbonate and polyether structures. Prepolymer preparation: 200g of carbon dioxide-based diol was added to a dry four-necked flask and vacuum dehydrated for 1h at 100℃ and a vacuum degree of -0.08MPa. After the dehydration was completed, nitrogen gas was introduced to cool the temperature to 60℃. 65g of toluene diisocyanate was added and 0.08g of dibutyltin dilaurate was added dropwise at a rate of 1 drop / second. The reaction was carried out at 80℃ for 2h to obtain an isocyanate-terminated polyurethane prepolymer. Chain extension and crosslinking: The polyurethane prepolymer was cooled to 70°C, and 8g of 1,4-butanediol and 3g of dimethylglyoxime were added. The reaction was carried out at 70°C for 1 hour to extend the chain and crosslink the polymer. The crosslinking agent reacted with the isocyanate groups at the end of the polyurethane prepolymer to form oxime carbamate bonds, thereby constructing a dynamic crosslinking network and obtaining the reactants. The reactants were cured in an oven at 100°C for 8 hours. After curing, the samples were removed and cooled to room temperature to obtain polyurethane elastomer materials. The molar ratio of isocyanate groups to hydroxyl groups is 1.0:1; the molar ratio of chain extender to carbon dioxide diol is 0.6:1; and the molar ratio of oxime groups to the terminal -NCO of polyurethane prepolymer in the crosslinking agent is 0.2:1.

[0039] Example 12

[0040] The number-average molecular weight of the carbon dioxide-based glycol is 2000 g / mol, and the carbon dioxide insertion rate in the carbon dioxide-based glycol is 30% (mass fraction); the carbon dioxide-based glycol segments contain polycarbonate and polyether structures. Prepolymer preparation: 200g of carbon dioxide-based diol was added to a dry four-necked flask and vacuum dehydrated for 1h at 100℃ and a vacuum degree of -0.08MPa. After the dehydration was completed, nitrogen gas was introduced to cool the temperature to 60℃. 65g of hexamethylene diisocyanate was added and 0.08g of dibutyltin dilaurate was added dropwise at a rate of 1 drop / second. The reaction was carried out at 80℃ for 2h to obtain an isocyanate-terminated polyurethane prepolymer. Chain extension and crosslinking: The polyurethane prepolymer was cooled to 70°C, and 8g of ethylene glycol and 3g of butanedione oxime were added. The reaction was carried out at 70°C for 1 hour to extend the chain and crosslink the polymer. The crosslinking agent reacted with the isocyanate groups at the end of the polyurethane prepolymer to form oxime carbamate bonds, thus constructing a dynamic crosslinking network and obtaining the reactants. The reactants were cured in an oven at 100°C for 8 hours. After curing, the samples were removed and cooled to room temperature to obtain polyurethane elastomer materials. The molar ratio of isocyanate groups to hydroxyl groups is 1.0:1; the molar ratio of chain extender to carbon dioxide diol is 0.6:1; and the molar ratio of oxime groups to the terminal -NCO of polyurethane prepolymer in the crosslinking agent is 0.2:1.

[0041] Example 13

[0042] The number-average molecular weight of the carbon dioxide-based glycol is 2000 g / mol, and the carbon dioxide insertion rate in the carbon dioxide-based glycol is 30% (mass fraction); the carbon dioxide-based glycol segments contain polycarbonate and polyether structures. Prepolymer preparation: 200g of carbon dioxide-based diol was added to a dry four-necked flask and vacuum dehydrated for 1h at 100℃ and a vacuum degree of -0.08MPa. After the dehydration was completed, nitrogen gas was introduced to cool the temperature to 60℃. 65g of isophorone diisocyanate was added and 0.08g of dibutyltin dilaurate was added dropwise at a rate of 1 drop / second. The reaction was carried out at 80℃ for 2h to obtain an isocyanate-terminated polyurethane prepolymer. Chain extension and crosslinking: The polyurethane prepolymer was cooled to 70°C, and 8g of diethylene glycol and 3g of butanedione oxime were added. The reaction was carried out at 70°C for 1 hour to extend the chain and crosslink the polymer. The crosslinking agent reacted with the isocyanate groups at the end of the polyurethane prepolymer to form oxime carbamate bonds, thus constructing a dynamic crosslinking network and obtaining the reactants. The reactants were cured in an oven at 100°C for 8 hours. After curing, the samples were removed and cooled to room temperature to obtain polyurethane elastomer materials. The molar ratio of isocyanate groups to hydroxyl groups is 1.0:1; the molar ratio of chain extender to carbon dioxide diol is 0.6:1; and the molar ratio of oxime groups to the terminal -NCO of polyurethane prepolymer in the crosslinking agent is 0.2:1.

[0043] Example 14

[0044] The number-average molecular weight of the carbon dioxide-based glycol is 2000 g / mol, and the carbon dioxide insertion rate in the carbon dioxide-based glycol is 30% (mass fraction); the carbon dioxide-based glycol segments contain polycarbonate and polyether structures. Prepolymer preparation: 200g of carbon dioxide-based diol was added to a dry four-necked flask and vacuum dehydrated for 1h at 100℃ and a vacuum degree of -0.08MPa. After the dehydration was completed, nitrogen gas was introduced to cool the temperature to 60℃. 65g of isophorone diisocyanate was added and 0.08g of dibutyltin dilaurate was added dropwise at a rate of 1 drop / second. The reaction was carried out at 80℃ for 2h to obtain an isocyanate-terminated polyurethane prepolymer. Chain extension and crosslinking: The polyurethane prepolymer was cooled to 70°C, and 8g hexanediol and 3g butanedione oxime were added. The reaction was carried out at 70°C for 1 hour to extend the chain and crosslink the polymer. The crosslinking agent reacted with the isocyanate groups at the end of the polyurethane prepolymer to form oxime carbamate bonds, thus constructing a dynamic crosslinking network and obtaining the reactants. The reactants were cured in an oven at 100°C for 8 hours. After curing, the samples were removed and cooled to room temperature to obtain polyurethane elastomer materials. The molar ratio of isocyanate groups to hydroxyl groups is 1.0:1; the molar ratio of chain extender to carbon dioxide diol is 0.6:1; and the molar ratio of oxime groups to the terminal -NCO of polyurethane prepolymer in the crosslinking agent is 0.2:1.

[0045] Example 15

[0046] The number-average molecular weight of the carbon dioxide-based glycol is 2000 g / mol, and the carbon dioxide insertion rate in the carbon dioxide-based glycol is 30% (mass fraction); the carbon dioxide-based glycol segments contain polycarbonate and polyether structures. Prepolymer preparation: 200g of carbon dioxide-based diol was added to a dry four-necked flask and vacuum dehydrated for 1h at 100℃ and a vacuum degree of -0.08MPa. After the dehydration was completed, nitrogen gas was introduced to cool the temperature to 60℃. 65g of isophorone diisocyanate was added and 0.08g of dibutyltin dilaurate was added dropwise at a rate of 1 drop / second. The reaction was carried out at 80℃ for 2h to obtain an isocyanate-terminated polyurethane prepolymer. Chain extension and crosslinking: The polyurethane prepolymer was cooled to 70°C, and 8g of ethylenediamine and 3g of dimethylglyoxime were added. The reaction was carried out at 70°C for 1 hour to extend the chain and crosslink the polymer. The crosslinking agent reacted with the isocyanate groups at the end of the polyurethane prepolymer to form oxime carbamate bonds, thus constructing a dynamic crosslinking network and obtaining the reactants. The reactants were cured in an oven at 100°C for 8 hours. After curing, the samples were removed and cooled to room temperature to obtain polyurethane elastomer materials. The molar ratio of isocyanate groups to hydroxyl groups is 1.0:1; the molar ratio of chain extender to carbon dioxide diol is 0.6:1; and the molar ratio of oxime groups to the terminal -NCO of polyurethane prepolymer in the crosslinking agent is 0.2:1.

[0047] Example 16

[0048] The number-average molecular weight of the carbon dioxide-based glycol is 2000 g / mol, and the carbon dioxide insertion rate in the carbon dioxide-based glycol is 30% (mass fraction); the carbon dioxide-based glycol segments contain polycarbonate and polyether structures. Prepolymer preparation: 200g of carbon dioxide-based diol was added to a dry four-necked flask and vacuum dehydrated for 1h at 100℃ and a vacuum degree of -0.08MPa. After the dehydration was completed, nitrogen gas was introduced to cool the temperature to 60℃. 65g of isophorone diisocyanate was added and 0.08g of dibutyltin dilaurate was added dropwise at a rate of 1 drop / second. The reaction was carried out at 80℃ for 2h to obtain an isocyanate-terminated polyurethane prepolymer. Chain extension and crosslinking: The polyurethane prepolymer was cooled to 70°C, and 8g of butanediamine and 3g of butanedione oxime were added. The reaction was carried out at 70°C for 1 hour to extend the chain and crosslink the polymer. The crosslinking agent reacted with the isocyanate groups at the end of the polyurethane prepolymer to form oxime carbamate bonds, thus constructing a dynamic crosslinking network and obtaining the reactants. The reactants were cured in an oven at 100°C for 8 hours. After curing, the samples were removed and cooled to room temperature to obtain polyurethane elastomer materials. The molar ratio of isocyanate groups to hydroxyl groups is 1.0:1; the molar ratio of chain extender to carbon dioxide diol is 0.6:1; and the molar ratio of oxime groups to the terminal -NCO of polyurethane prepolymer in the crosslinking agent is 0.2:1.

[0049] Example 17

[0050] The number-average molecular weight of the carbon dioxide-based glycol is 2000 g / mol, and the carbon dioxide insertion rate in the carbon dioxide-based glycol is 30% (mass fraction); the carbon dioxide-based glycol segments contain polycarbonate and polyether structures. Prepolymer preparation: 200g of carbon dioxide-based diol was added to a dry four-necked flask and vacuum dehydrated for 1h at 100℃ and a vacuum degree of -0.08MPa. After the dehydration was completed, nitrogen gas was introduced to cool the temperature to 60℃. 65g of isophorone diisocyanate was added and 0.08g of dibutyltin dilaurate was added dropwise at a rate of 1 drop / second. The reaction was carried out at 80℃ for 2h to obtain an isocyanate-terminated polyurethane prepolymer. Chain extension and crosslinking: The polyurethane prepolymer was cooled to 70°C, and 8g of 1,4-butanediol and 3g of cyclohexanedione dioxime were added. The reaction was carried out at 70°C for 1 hour to extend the chain and crosslink the polymer. The crosslinking agent reacted with the isocyanate groups at the end of the polyurethane prepolymer to form oxime carbamate bonds, thus constructing a dynamic crosslinking network and obtaining the reactants. The reactants were cured in an oven at 100°C for 8 hours. After curing, the samples were removed and cooled to room temperature to obtain polyurethane elastomer materials. The molar ratio of isocyanate groups to hydroxyl groups is 1.0:1; the molar ratio of chain extender to carbon dioxide diol is 0.6:1; and the molar ratio of oxime groups to the terminal -NCO of polyurethane prepolymer in the crosslinking agent is 0.2:1.

[0051] Example 18

[0052] The number-average molecular weight of the carbon dioxide-based glycol is 2000 g / mol, and the carbon dioxide insertion rate in the carbon dioxide-based glycol is 30% (mass fraction); the carbon dioxide-based glycol segments contain polycarbonate and polyether structures. Prepolymer preparation: 200g of carbon dioxide-based diol was added to a dry four-necked flask and vacuum dehydrated for 1h at 100℃ and a vacuum degree of -0.08MPa. After the dehydration was completed, nitrogen gas was introduced to cool the temperature to 60℃. 65g of isophorone diisocyanate was added and 0.08g of dibutyltin dilaurate was added dropwise at a rate of 1 drop / second. The reaction was carried out at 80℃ for 2h to obtain an isocyanate-terminated polyurethane prepolymer. Chain extension and crosslinking: The polyurethane prepolymer was cooled to 70°C, and 8g of 1,4-butanediol and 3g of p-benzoquinone dioxime were added. The reaction was carried out at 70°C for 1 hour to extend the chain and crosslink the polymer. The crosslinking agent reacted with the isocyanate groups at the end of the polyurethane prepolymer to form oxime carbamate bonds, thus constructing a dynamic crosslinking network and obtaining the reactants. The reactants were cured in an oven at 100°C for 8 hours. After curing, the samples were removed and cooled to room temperature to obtain polyurethane elastomer materials. The molar ratio of isocyanate groups to hydroxyl groups is 1.0:1; the molar ratio of chain extender to carbon dioxide diol is 0.6:1; and the molar ratio of oxime groups to the terminal -NCO of polyurethane prepolymer in the crosslinking agent is 0.2:1.

[0053] Comparative Example 1 The number-average molecular weight of the carbon dioxide-based glycol is 2000 g / mol, and the carbon dioxide insertion rate in the carbon dioxide-based glycol is 30% (mass fraction); the carbon dioxide-based glycol segments contain polycarbonate and polyether structures. Prepolymer preparation: 200g of carbon dioxide-based diol was added to a dry four-necked flask and vacuum dehydrated for 1h at 100℃ and a vacuum degree of -0.08MPa. After the dehydration was completed, nitrogen gas was introduced to cool the temperature to 60℃. 65g of isophorone diisocyanate was added and 0.08g of dibutyltin dilaurate was added dropwise at a rate of 1 drop / second. The reaction was carried out at 80℃ for 2h to obtain an isocyanate-terminated polyurethane prepolymer. Chain extension and crosslinking: The polyurethane prepolymer was cooled to 70°C, and 8g of 1,4-butanediol was added. The reaction was carried out at 70°C for 1h to perform chain extension and crosslinking. The crosslinking agent reacted with the isocyanate groups at the end of the polyurethane prepolymer to form oxime carbamate bonds, thus constructing a dynamic crosslinking network and obtaining the reactants. The reactants were cured in an oven at 100°C for 8 hours. After curing, the samples were removed and cooled to room temperature to obtain polyurethane elastomer materials. The molar ratio of isocyanate groups to hydroxyl groups is 1.0:1; the molar ratio of chain extender to carbon dioxide diol is 0.6:1; and the molar ratio of oxime groups to the terminal -NCO of polyurethane prepolymer in the crosslinking agent is 0.2:1.

[0054] Performance testing The tensile strength and elongation at break properties of the polyurethane elastomer materials prepared in Examples 1-18 and Comparative Example 1 were tested in accordance with GB / T1040.1-2018 Plastics—Determination of tensile properties—Part 1: General. Self-healing performance: The sample was cut into a dumbbell shape, cut off from the middle with a blade, and then the cut surfaces were tightly joined together. After being placed at room temperature for 24 hours, the sample was subjected to a tensile test to determine the tensile strength recovery rate after healing. Thermal properties: Differential scanning calorimetry (DSC) analysis was used to analyze the glass transition temperature and decomposition temperature of the samples; The test results are shown in the table below.

[0055] As can be seen from the table above, the tensile strength of the embodiment is 24-28 MPa and the elongation at break is 716-720%, which is significantly improved compared with the tensile strength of the comparative example (21 MPa) and the elongation at break (586%), thus balancing high strength and high toughness. The room temperature self-healing recovery rate is 91-95%, which is much higher than the 88% of the comparative example, indicating better recovery of mechanical properties after damage. In terms of thermal properties, the glass transition temperature of the embodiment is as low as -20~-15℃, with better low-temperature elasticity, and the thermal decomposition temperature is 265-280℃, which is more stable than the glass transition temperature of the comparative example (-13℃) and the thermal decomposition temperature (247℃).

[0056] The embodiments described above are merely examples of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.

Claims

1. A carbon dioxide basic signature self-repairing polyurethane elastomer material, characterized by, The polyurethane elastomer material comprises, by weight: 180-220g of carbon dioxide-based diol, 60-80g of isocyanate, 8-12g of chain extender, 1-3g of crosslinking agent, and 0.06-0.1g of catalyst.

2. The carbon dioxide-based self-healing polyurethane elastomer material according to claim 1, characterized in that, The number-average molecular weight of the carbon dioxide-based diol is 1000-3000 g / mol, and the carbon dioxide insertion rate in the carbon dioxide-based diol is 5-40% (mass fraction); the carbon dioxide-based diol segments contain polycarbonate and polyether structures.

3. The carbon dioxide-based self-healing polyurethane elastomer material according to claim 1, characterized in that, The isocyanate is selected from one or more of 4,4'-diphenylmethane diisocyanate, toluene diisocyanate, hexamethylene diisocyanate, and isophorone diisocyanate.

4. The carbon dioxide-based self-healing polyurethane elastomer material according to claim 1, characterized in that, The chain extender is selected from one or more of 1,4-butanediol, ethylene glycol, diethylene glycol, hexanediol, ethylenediamine, and butanediamine.

5. The carbon dioxide-based self-healing polyurethane elastomer material according to claim 1, characterized in that, The crosslinking agent is selected from one or more of dimethylglyoxime, cyclohexanedione dioxime, and p-benzoquinone dioxime.

6. The carbon dioxide-based self-healing polyurethane elastomer material according to claim 1, characterized in that, The catalyst used is dibutyltin dilaurate.

7. A method for preparing a carbon dioxide-based self-healing polyurethane elastomer material according to any one of claims 1-6, characterized in that, Includes the following steps: a. Preparation of prepolymer: Carbon dioxide-based diol is added to a dry four-necked flask and vacuum dehydrated at 60-120℃ and a vacuum degree of -0.08~-0.1MPa for 1-2 hours. After dehydration, nitrogen gas is introduced to cool the temperature to 40-60℃. Isocyanate is added and catalyst is added dropwise at a rate of 1-2 drops / second. The reaction is carried out at 50-90℃ for 0.5-2 hours to obtain isocyanate-terminated polyurethane prepolymer. b. Chain extension and crosslinking: The polyurethane prepolymer is cooled to 70°C, and a chain extender and a crosslinking agent are added. The reaction is carried out at 70°C for 0.5-2 hours to extend the chain and crosslink the polymer. The crosslinking agent reacts with the isocyanate groups at the end of the polyurethane prepolymer to form oxime carbamate bonds, thereby constructing a dynamic crosslinking network and obtaining the reactants. c. Cure the reactants in an oven at 80-120℃ for 12-18 hours. After curing, remove the sample and cool it to room temperature to obtain polyurethane elastomer material.

8. The method for preparing a carbon dioxide-based self-healing polyurethane elastomer material according to claim 7, characterized in that, The molar ratio of isocyanate groups to hydroxyl groups is 1.0-1.5:1; the molar ratio of chain extender to carbon dioxide diol is 0.2-0.8:1; and the molar ratio of oxime groups to the terminal -NCO of polyurethane prepolymer in the crosslinking agent is 0.05-0.3:1.

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