High-strength and high-toughness anti-aging two-component polyurethane and preparation method thereof

Abstract

The application discloses a two-component polyurethane with high strength, high toughness, aging resistance and fluorescent performance, which comprises an A component and a B component. The A component is prepared from an oligomer polyol, an aliphatic isocyanate, a hydrazide chain extender, a polyol small molecule crosslinking agent and a metal ion crosslinking agent. The B component is a fluorine-containing segment modified isocyanate. The application introduces a hydrazide group and a metal ion into the A component, so that the A component is rich in hydrogen bonds and metal coordination bonds, and the strength and toughness of the two-component polyurethane are enhanced. Even the two-component polyurethane can be endowed with fluorescent performance by introducing rare earth ions, and the application of the two-component polyurethane is expanded. After the A component and the B component are cured, the organic fluorine segment in the B component and the aging-resistant material in the A component synergistically enhance the aging resistance of the two-component polyurethane.

Description

[0001] Field of study

[0002] This invention relates to the field of coating technology, specifically to a high-strength, high-toughness, and aging-resistant two-component polyurethane and its preparation method. Background Technology

[0003] Polyurethane possesses excellent properties such as high wear resistance and high elasticity, and is widely used in many fields such as aerospace, marine, and construction. However, as its service conditions become more demanding, the requirements for its multi-functionality are increasing. In particular, it is often difficult to achieve both strength and toughness in polyurethane materials. Polyurethanes with high tensile strength often suffer from low elongation at break and low toughness due to poor molecular chain migration. Currently, there is considerable research on single-component strong and tough polyurethanes. However, single-component polyurethanes often lack both strength and toughness and are prone to aging.

[0004] Two-component polyurethane has many advantages over single-component polyurethane. When used in coatings, two-component polyurethane can rapidly crosslink to form strength, and its performance covers a wide range of mechanical properties, from viscoelastic to highly structural. However, due to interfacial defects in the pigment / filler / resin matrix and the susceptibility of curing to moisture interference, the strength of two-component coatings is insufficient. Therefore, there are currently few reported strong and tough two-component polyurethanes. Jiang Zhiguo of Beijing University of Chemical Technology synthesized an isocyanate-terminated A component using polytetrahydrofuran glycol, polyethylene adipate, polypropylene oxide polyol, and toluene diisocyanate as raw materials. He then cured this component with 3,3'-dichloro-4,4'-diaminodiphenylmethane to synthesize a polyurethane potting compound with a tensile strength of 56 MPa and an elongation at break of 581%. However, the use of an aromatic curing agent resulted in poor weather resistance of the invented potting compound. Patent US 2019 / 0322912 A1 also reports a two-component polyurethane with a maximum tensile strength of only 23 MPa. Apart from this, the tensile strengths of other reported two-component polyurethanes are mostly concentrated in the range of 10-25 MPa.

[0005] High-performance two-component polyurethanes are typically obtained through several methods: 1) Designing aromatic polyurethanes, which have superior mechanical properties compared to aliphatic polyurethanes; however, the presence of benzene rings inevitably leads to poor weather resistance and aging. 2) Introducing nanofillers, such as silica, natural fibers, and graphene, into the system; however, this method sacrifices elongation while enhancing mechanical properties. Furthermore, polyurethane coatings inevitably experience yellowing, cracking, and other aging phenomena during outdoor use, affecting not only the coating's appearance but also further degrading film performance. To meet increasingly demanding service conditions, research into aging-resistant two-component polyurethanes is also urgently needed.

[0006] Therefore, developing a two-component polyurethane resin with high strength, high toughness and aging resistance has become an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0007] To address the problems existing in the prior art, this invention provides a high-strength, high-toughness, and aging-resistant two-component polyurethane to meet the protective requirements of two-component polyurethane coatings under outdoor and harsh conditions. The high-strength, high-toughness, and aging-resistant two-component polyurethane of this invention contains hydrazide groups, which, in addition to providing hydrogen bonding, can also form metal-ion coordination bonds with metal ions, providing metal coordination. The introduction of hydrazide groups and metal ions enriches component A with hydrogen bonds and metal-ion coordination bonds, simultaneously enhancing the strength and toughness of the polyurethane. Furthermore, the introduction of rare earth ions can further impart fluorescent properties to the two-component polyurethane. Simultaneously, after component A and component B are cured, the introduction of organic fluorine segments further enhances the aging resistance of the two-component polyurethane.

[0008] One objective of this invention is to provide a high-strength, high-toughness, and aging-resistant two-component polyurethane. The two-component polyurethane comprises component A and component B; the weight ratio of component A to component B is 1:0.1–1.2; wherein,

[0009] Component A is prepared from raw materials comprising the following components:

[0010] Each component, by weight,

[0011]

[0012] The structural formula of component B is as follows:

[0013]

[0014] In a preferred embodiment of the present invention, in component A, each component is expressed in parts by weight.

[0015]

[0016] In a preferred embodiment of the present invention, the aliphatic isocyanate is at least one selected from isophorone diisocyanate, 1,4-cyclohexane diisocyanate, hexamethylene diisocyanate, and dicyclohexylmethane diisocyanate; the acylhydrazine chain extender is at least one selected from isophthalic acid dihydrazine, malonylhydrazine, succinic acid dihydrazine, adipic acid dihydrazine, and sebadecylhydrazine; the catalyst is at least one selected from organotin catalysts, organobismuth catalysts, and tertiary amine catalysts; and the oligomeric polyol is a poly… The polyol contains at least one of carbonate polyol, polycaprolactone polyol, polytetrahydrofuran polyol, and hydroxyl-terminated polybutadiene; the small molecule crosslinking agent of the polyol is at least one of trimethylolpropane, 2-amino-2-methyl-1,3-propanediol, serinel, and 2-amino-2-methyl-1,3-propanediol; the metal ion crosslinking agent is at least one of ZnCl2, Zn(CF3SO3)2, Zn(CF3COO)2, FeCl3, EuCl3, and TbCl3. Technicians may select appropriate aliphatic isocyanates, hydrazide chain extenders, oligomeric polyols, small molecule crosslinking agents of polyols, metal ion crosslinking agents, and catalyst types and dosages as appropriate.

[0017] In a preferred embodiment of the present invention, the weight ratio of the aliphatic isocyanate, the catalyst, and the acylhydrazine chain extender is 20:0.2–5:0.5–20; preferably 20:0.2–3:1.6–12; more preferably, the weight ratio of component A to component B is 1:0.8–1.2. Those skilled in the art can select appropriate weight ratios for the catalyst to aliphatic isocyanate, the aliphatic isocyanate to acylhydrazine chain extender, and the component A to component B as appropriate.

[0018] In a preferred embodiment of the present invention, component A is prepared by the following steps:

[0019] (1) Dissolve the aliphatic isocyanate and the hydrazide chain extender in the first solvent and the second solvent respectively, mix them, add some catalyst, heat and react to obtain aliphatic isocyanate-terminated polyurethane prepolymer.

[0020] (2) Add the remaining catalyst to the aliphatic isocyanate-terminated polyurethane prepolymer of step (1), and add the oligomer polyol and the polyol small molecule crosslinking agent at 100-120°C, and heat to react to obtain hydroxyl-terminated polyurethane.

[0021] (3) Add the metal ion crosslinking agent dissolved in a third solvent to the hydroxyl-terminated polyurethane of step (2) to obtain component A;

[0022] In step (1), the catalyst is 30-40 wt% of the total catalyst in component A.

[0023] The present invention can specifically adopt the following technical solutions:

[0024] Component A is prepared through the following steps:

[0025] (1) Synthesis of isocyanate-terminated polyurethane prepolymer: Aliphatic isocyanate and hydrazine chain extender are dissolved in a first solvent and a second solvent, respectively. The hydrazine chain extender dissolved in the second solvent is added dropwise to the isocyanate solution dissolved in the first solvent. The reaction is heated for a certain time in the presence of a partial catalyst to obtain an aliphatic isocyanate-terminated polyurethane prepolymer. Specifically, an aliphatic isocyanate-terminated polyurethane prepolymer containing hydrazine groups is obtained through a condensation reaction. The hydrazine groups, in addition to providing hydrogen bonding, can also form metal-ion coordination bonds with metal ions, providing metal coordination. The aliphatic isocyanate-terminated polyurethane prepolymer containing hydrazine groups is a compound with the following structure:

[0026]

[0027] (2) Synthesis of hydroxyl-terminated polyurethane: The remaining catalyst was added to the above reaction system, and the pre-heat-treated oligomer polyol and polyol small molecule crosslinking agent were added to the above isocyanate-terminated polyurethane prepolymer reaction system and heated for a period of time to obtain hydroxyl-terminated polyurethane.

[0028] (3) Synthesis of hydroxyl-terminated polyurethane containing hydrogen bonds and metal coordination bonds: Dissolve an appropriate metal ion crosslinking agent in a third solvent and add it to the hydroxyl-terminated polyurethane obtained in step (2). Stir and mix evenly to obtain hydroxyl-terminated polyurethane containing hydrogen bonds and metal coordination bonds, which is component A. If the metal ion crosslinking agent is a rare earth ion, it will further endow the system with fluorescence properties.

[0029] In a preferred embodiment of the present invention, the first solvent is at least one selected from ethyl acetate, butyl acetate, xylene, propylene glycol methyl ether acetate, butanone, and n-hexane; the second solvent is at least one selected from N-methylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, isophorone, and cyclohexanone; and the third solvent is at least one selected from acetonitrile, tetrahydrofuran, propylene glycol methyl ether acetate, chloroform, N,N-dimethylformamide, and dichloromethane. The total amount of the first solvent, the second solvent, and the third solvent is 1 to 100 parts by weight; preferably 80 to 100 parts by weight. Those skilled in the art can select appropriate types and amounts of the first, second, and third solvents as needed.

[0030] In a preferred embodiment of the present invention, the mass ratio of the first solvent to the aliphatic isocyanate is 1–3:1, preferably 2–3:1; the mass ratio of the second solvent to the acylhydrazine chain extender is 20:1–10, preferably 20:4–7; the mass ratio of the third solvent to the metal ion crosslinking agent is 10:0.1–3, preferably 10:0.1–1; and the mass ratio of the first solvent to the catalyst is 100:0.1–2, preferably 100:0.5–1.5. Those skilled in the art can select appropriate weight ratios for the first solvent to the aliphatic isocyanate, the second solvent to the acylhydrazine chain extender, the third solvent to the metal ion crosslinking agent, and the first solvent to the catalyst as appropriate.

[0031] In a preferred embodiment of the present invention, in step (1), the reaction temperature is 50–100°C, preferably 70–90°C; the reaction time is 0.5–4 h, preferably 1–2 h; in step (2), the reaction temperature is 70–110°C, preferably 80–100°C; the reaction time is 1–6 h, preferably 2–4 h. Those skilled in the art can select appropriate reaction temperatures and reaction times as needed.

[0032] A second objective of this invention is to provide a method for preparing a high-strength, high-toughness, and aging-resistant two-component polyurethane, which is one of the objectives of this invention. The method includes: mixing component A and component B according to the stated amounts, adding a solvent, evaporating the mixture, and heating to cure it, thereby obtaining the high-strength, high-toughness, and aging-resistant two-component polyurethane.

[0033] The solvent is the first solvent mentioned above. The first solvent is at least one selected from ethyl acetate, butyl acetate, xylene, propylene glycol methyl ether acetate, butanone, and n-hexane.

[0034] Specifically: Hydroxyl-terminated polyurethane (component A) containing hydrogen bonds and metal coordination bonds is mixed with component B (fluorinated segment modified isocyanate curing agent) and stirred evenly. An appropriate amount of the first solvent is taken for dilution, and the mixture is placed in a tetrafluoroethylene mold to evaporate the solvent and form a film. The film is then heated to cure and remove the solvent, resulting in a two-component polyurethane with high strength, high toughness, aging resistance, and fluorescent properties.

[0035] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0036] 1) The high-strength, high-toughness, and aging-resistant two-component polyurethane of this invention can be obtained as a hydroxyl-terminated polyurethane (component A) rich in hydrogen bonds and metal coordination bonds by introducing hydrazide groups and metal ions. The introduction of supramolecular effects (hydrogen bonds / metal coordination bonds) can simultaneously enhance the strength and toughness of component A. Its strength and toughness can be adjusted by regulating the ratio and type of hydrazide groups and metal ions.

[0037] 2) The high-strength, high-toughness, and aging-resistant two-component polyurethane of the present invention can also selectively form metal ion coordination bonds with rare earth ions and hydrazide groups to further endow the system with fluorescence properties and expand its applications.

[0038] 3) In the high-strength, high-toughness, and aging-resistant two-component polyurethane of this invention, component B is a fluorinated segment modified isocyanate curing agent. Components A and B are cross-linked and cured to obtain a two-component polyurethane with both strength and toughness. The synergistic effect of the aging-resistant raw materials (isocyanate, oligomeric polyol) in component A and the fluorinated segment modified isocyanate curing agent in component B gives the obtained high-strength, high-toughness two-component polyurethane excellent aging resistance.

[0039] 4) The method of preparing high-strength, high-toughness and aging-resistant two-component polyurethane of the present invention has readily available raw materials, a simple and easy-to-control synthesis process, no need for specific equipment, and a high yield. Attached Figure Description

[0040] Figure 1 This is a schematic diagram showing the fluorescence properties of the high-strength, high-toughness, and aging-resistant two-component polyurethane prepared in Example 4 of the present invention under ultraviolet light irradiation.

[0041] Figure 2 This is a schematic diagram showing the fluorescence properties of the high-strength, high-toughness, and aging-resistant two-component polyurethane prepared in Example 5 of the present invention under ultraviolet light irradiation. Detailed Implementation

[0042] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that the following embodiments are only used to further illustrate the present invention and should not be construed as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the content of the present invention are still within the scope of protection of the present invention.

[0043] All raw materials used in the examples were commercially available and conventional. All instruments used in the examples were conventional instruments. Component B was obtained using the preparation method described in Example 2 of CN101143840A, and will not be repeated here.

[0044] Example 1

[0045] (1) Synthesis of isocyanate-terminated polyurethane prepolymer: 20 parts of 1,4-cyclohexane diisocyanate cyanate and 2 parts of isophthalic acid dihydrazide chain extender were dissolved in 35 parts of butyl acetate and 25 parts of N,N-dimethylformamide, respectively. The isophthalic acid dihydrazide chain extender dissolved in N,N-dimethylformamide was added dropwise to the dicyclohexylmethane diisocyanate solution dissolved in butyl acetate, and the reaction was carried out at 70°C for 2 h in the presence of 0.3 parts of organotin catalyst to obtain aliphatic isocyanate-terminated polyurethane prepolymer;

[0046] (2) Synthesis of hydroxyl-terminated polyurethane: By weight, 0.5 parts of organotin catalyst were added to the above reaction system, and 100 parts of polycarbonate polyol that had been pre-treated by heating to remove water at 110℃ and 3 parts of trimethylolpropane were added to the above reaction system of isocyanate-terminated polyurethane prepolymer. The reaction was carried out at 90℃ for 3 hours to obtain hydroxyl-terminated polyurethane.

[0047] (3) Synthesis of hydroxyl-terminated polyurethane containing hydrogen bonds and metal coordination bonds: Take 0.1 parts of Zn(CF3SO3)2 crosslinking agent and dissolve it in 10 parts of acetonitrile. Add it to the hydroxyl-terminated polyurethane obtained in step (2) and stir to mix evenly to obtain hydroxyl-terminated polyurethane containing hydrogen bonds and metal coordination bonds, which is component A.

[0048] (4) Synthesis of high-strength, high-toughness, and aging-resistant two-component polyurethane: By weight, 1 part of hydroxyl-terminated polyurethane (component A) containing hydrogen bonds and metal coordination bonds obtained in step (3) is mixed with 1.2 parts of component B (fluorine-containing segment modified isocyanate curing agent) and stirred evenly. 2 parts of butyl acetate are diluted, placed in a tetrafluoroethylene mold to evaporate the solvent and form a film. The film is then heated and cured to remove the solvent, thus obtaining a high-strength, high-toughness, and aging-resistant two-component polyurethane.

[0049] Example 2

[0050] (1) Synthesis of isocyanate-terminated polyurethane prepolymer: 20 parts of 1,4-cyclohexane diisocyanate cyanate and 2 parts of malonyl hydrazine chain extender were dissolved in 35 parts of xylene and 25 parts of N-methylpyrrolidone, respectively. The malonyl hydrazine chain extender dissolved in N-methylpyrrolidone was added dropwise to the isophorone diisocyanate solution dissolved in xylene. The reaction was carried out at 70°C for 2 h in the presence of 0.3 parts of organotin catalyst to obtain aliphatic isocyanate-terminated polyurethane prepolymer.

[0051] (2) Synthesis of hydroxyl-terminated polyurethane: By weight, 0.5 parts of organotin catalyst were added to the above reaction system, and 100 parts of polycarbonate polyol that had been pre-treated by heating to remove water at 110℃ and 3 parts of trimethylolpropane were added to the reaction system of the above isocyanate-terminated polyurethane prepolymer. The reaction was carried out at 90℃ for 3 hours to obtain hydroxyl-terminated polyurethane;

[0052] (3) Synthesis of hydroxyl-terminated polyurethane containing hydrogen bonds and metal coordination bonds: Take 0.1 parts of Zn(CF3SO3)2 crosslinking agent and dissolve it in 10 parts of tetrahydrofuran. Add it to the hydroxyl-terminated polyurethane obtained in step (2) and stir to mix evenly to obtain hydroxyl-terminated polyurethane containing hydrogen bonds and metal coordination bonds, which is component A.

[0053] (4) Synthesis of high-strength, high-toughness, and aging-resistant two-component polyurethane: 1 part of hydroxyl-terminated polyurethane (component A) containing hydrogen bonds and metal coordination bonds obtained in step (3) is mixed with 1.2 parts of component B (fluorine-containing segment modified isocyanate curing agent) and stirred evenly. 2 parts of xylene are taken for dilution, placed in a tetrafluoroethylene mold to evaporate the solvent and form a film. The film is then heated and cured to remove the solvent, thus obtaining a high-strength, high-toughness, and aging-resistant two-component polyurethane.

[0054] Example 3

[0055] (1) Synthesis of isocyanate-terminated polyurethane prepolymer: 20 parts of 1,4-cyclohexane diisocyanate cyanate and 2 parts of succinic acid dihydrazide chain extender were dissolved in 35 parts of propylene glycol methyl ether acetate and 25 parts of N,N-dimethylacetamide, respectively. The succinic acid dihydrazide chain extender dissolved in N,N-dimethylacetamide was added dropwise to the isocyanate solution dissolved in propylene glycol methyl ether acetate, and the reaction was carried out at 70°C for 2 h in the presence of 0.3 parts of organotin catalyst to obtain aliphatic isocyanate-terminated polyurethane prepolymer;

[0056] (2) Synthesis of hydroxyl-terminated polyurethane: By weight, 0.5 parts of organotin catalyst were added to the above reaction system, and 100 parts of polycarbonate polyol that had been pre-treated by heating to remove water at 110℃ and 3 parts of trimethylolpropane were added to the reaction system of the above isocyanate-terminated polyurethane prepolymer. The reaction was carried out at 90℃ for 3 hours to obtain hydroxyl-terminated polyurethane;

[0057] (3) Synthesis of hydroxyl-terminated polyurethane containing hydrogen bonds and metal coordination bonds: Take 0.1 parts of Zn(CF3SO3)2 crosslinking agent and dissolve it in 10 parts of dichloromethane. Add it to the hydroxyl-terminated polyurethane obtained in step (2) and stir to mix evenly to obtain hydroxyl-terminated polyurethane containing hydrogen bonds and metal coordination bonds, which is component A.

[0058] (4) Synthesis of high-strength, high-toughness, and aging-resistant two-component polyurethane: By weight, 1 part of hydroxyl-terminated polyurethane (component A) containing hydrogen bonds and metal coordination bonds obtained in step (3) is mixed with 1.2 parts of component B (fluorine-containing segment modified isocyanate curing agent) and stirred evenly. 2 parts of propylene glycol methyl ether acetate are diluted, placed in a tetrafluoroethylene mold to evaporate the solvent and form a film. The film is then heated and cured to remove the solvent, thus obtaining a high-strength, high-toughness, and aging-resistant two-component polyurethane.

[0059] Example 4

[0060] (1) Synthesis of isocyanate-terminated polyurethane prepolymer: 20 parts of 1,4-cyclohexane diisocyanate cyanate and 2 parts of succinic acid dihydrazide chain extender were dissolved in 35 parts of propylene glycol methyl ether acetate and 25 parts of N,N-dimethylacetamide, respectively. The succinic acid dihydrazide chain extender dissolved in N,N-dimethylacetamide was added dropwise to the isocyanate solution dissolved in propylene glycol methyl ether acetate, and the reaction was carried out at 70°C for 2 h in the presence of 0.3 parts of organotin catalyst to obtain aliphatic isocyanate-terminated polyurethane prepolymer;

[0061] (2) Synthesis of hydroxyl-terminated polyurethane: By weight, 0.5 parts of organotin catalyst were added to the above reaction system, and 100 parts of polycarbonate polyol that had been pre-treated by heating to remove water at 110℃ and 3 parts of trimethylolpropane were added to the reaction system of the above isocyanate-terminated polyurethane prepolymer. The reaction was carried out at 90℃ for 3 hours to obtain hydroxyl-terminated polyurethane;

[0062] (3) Synthesis of hydroxyl-terminated polyurethane containing hydrogen bonds and metal coordination bonds: Take 0.1 parts of EuCl3 crosslinking agent and dissolve it in 10 parts of acetonitrile, add it to the hydroxyl-terminated polyurethane obtained in step (2), stir and mix evenly to obtain hydroxyl-terminated polyurethane containing hydrogen bonds and metal coordination bonds, which is component A.

[0063] (4) Synthesis of high-strength, high-toughness, aging-resistant and fluorescent two-component polyurethane: By weight, 1 part of hydroxyl-terminated polyurethane (component A) containing hydrogen bonds and metal coordination bonds obtained in step (3) is mixed with 1.2 parts of component B (fluorine-containing segment modified isocyanate curing agent) and stirred evenly. 2 parts of propylene glycol methyl ether acetate are diluted, placed in a tetrafluoroethylene mold to evaporate the solvent and form a film. The film is then heated to cure and remove the solvent to obtain a high-strength, high-toughness, aging-resistant and fluorescent two-component polyurethane.

[0064] Example 5

[0065] (1) Synthesis of isocyanate-terminated polyurethane prepolymer: 20 parts of 1,4-cyclohexane diisocyanate cyanate and 2 parts of succinic acid dihydrazide chain extender were dissolved in 35 parts of propylene glycol methyl ether acetate and 25 parts of N,N-dimethylacetamide, respectively. The succinic acid dihydrazide chain extender dissolved in N,N-dimethylacetamide was added dropwise to the isocyanate solution dissolved in propylene glycol methyl ether acetate, and the reaction was carried out at 70°C for 2 h in the presence of 0.3 parts of organotin catalyst to obtain aliphatic isocyanate-terminated polyurethane prepolymer;

[0066] (2) Synthesis of hydroxyl-terminated polyurethane: By weight, 0.5 parts of organotin catalyst were added to the above reaction system, and 100 parts of polycarbonate polyol that had been pre-treated by heating to remove water at 110℃ and 3 parts of trimethylolpropane were added to the reaction system of the above isocyanate-terminated polyurethane prepolymer. The reaction was carried out at 90℃ for 3 hours to obtain hydroxyl-terminated polyurethane;

[0067] (3) Synthesis of hydroxyl-terminated polyurethane containing hydrogen bonds and metal coordination bonds: Take 0.1 parts of TbCl3 crosslinking agent and dissolve it in 10 parts of acetonitrile, add it to the hydroxyl-terminated polyurethane obtained in step (2), stir and mix evenly to obtain hydroxyl-terminated polyurethane containing hydrogen bonds and metal coordination bonds, which is component A.

[0068] (4) Synthesis of high-strength, high-toughness, aging-resistant and fluorescent two-component polyurethane: By weight, 1 part of hydroxyl-terminated polyurethane (component A) containing hydrogen bonds and metal coordination bonds obtained in step (3) is mixed with 1.2 parts of component B (fluorine-containing segment modified isocyanate curing agent) and stirred evenly. 2 parts of propylene glycol methyl ether acetate are diluted, placed in a tetrafluoroethylene mold to evaporate the solvent and form a film. The film is then heated to cure and remove the solvent to obtain a high-strength, high-toughness, aging-resistant and fluorescent two-component polyurethane.

[0069] Example 6

[0070] (1) Synthesis of isocyanate-terminated polyurethane prepolymer: 20 parts of 1,4-cyclohexane diisocyanate cyanate and 5 parts of succinic acid dihydrazide chain extender were dissolved in 35 parts of butyl acetate and 25 parts of N,N-dimethylformamide, respectively. The isophthalic acid dihydrazide chain extender dissolved in N,N-dimethylformamide was added dropwise to the dicyclohexylmethane diisocyanate solution dissolved in butyl acetate. The reaction was carried out at 70°C for 2 h in the presence of 0.3 parts of organotin catalyst to obtain aliphatic isocyanate-terminated polyurethane prepolymer.

[0071] (2) Synthesis of hydroxyl-terminated polyurethane: By weight, 0.5 parts of organotin catalyst were added to the above reaction system, and 100 parts of polycarbonate polyol that had been pre-treated by heating to remove water at 110℃ and 3 parts of trimethylolpropane were added to the above reaction system of isocyanate-terminated polyurethane prepolymer. The reaction was carried out at 90℃ for 3 hours to obtain hydroxyl-terminated polyurethane.

[0072] (3) Synthesis of hydroxyl-terminated polyurethane containing hydrogen bonds and metal coordination bonds: Take 0.1 parts of Zn(CF3SO3)2 crosslinking agent and dissolve it in 10 parts of acetonitrile. Add it to the hydroxyl-terminated polyurethane obtained in step (2) and stir to mix evenly to obtain hydroxyl-terminated polyurethane containing hydrogen bonds and metal coordination bonds, which is component A.

[0073] (4) Synthesis of high-strength, high-toughness, and aging-resistant two-component polyurethane: By weight, 1 part of hydroxyl-terminated polyurethane (component A) containing hydrogen bonds and metal coordination bonds obtained in step (3) is mixed with 1.2 parts of component B (fluorine-containing segment modified isocyanate curing agent) and stirred evenly. 2 parts of butyl acetate are diluted, placed in a tetrafluoroethylene mold to evaporate the solvent and form a film. The film is then heated and cured to remove the solvent, thus obtaining a high-strength, high-toughness, and aging-resistant two-component polyurethane.

[0074] Example 7

[0075] (1) Synthesis of isocyanate-terminated polyurethane prepolymer: 20 parts of 1,4-cyclohexane diisocyanate cyanate and 2 parts of succinic acid dihydrazide chain extender were dissolved in 35 parts of butyl acetate and 25 parts of N,N-dimethylformamide, respectively. The isophthalic acid dihydrazide chain extender dissolved in N,N-dimethylformamide was added dropwise to the dicyclohexylmethane diisocyanate solution dissolved in butyl acetate. The reaction was carried out at 70°C for 2 h in the presence of 0.3 parts of organotin catalyst to obtain aliphatic isocyanate-terminated polyurethane prepolymer.

[0076] (2) Synthesis of hydroxyl-terminated polyurethane: By weight, 0.5 parts of organotin catalyst were added to the above reaction system, and 100 parts of polycarbonate polyol that had been pre-treated by heating to remove water at 110℃ and 3 parts of trimethylolpropane were added to the above reaction system of isocyanate-terminated polyurethane prepolymer. The reaction was carried out at 90℃ for 3 hours to obtain hydroxyl-terminated polyurethane.

[0077] (3) Synthesis of hydroxyl-terminated polyurethane containing hydrogen bonds and metal coordination bonds: Take 1 part of Zn(CF3SO3)2 crosslinking agent and dissolve it in 10 parts of acetonitrile. Add it to the hydroxyl-terminated polyurethane obtained in step (2) and stir to mix evenly to obtain hydroxyl-terminated polyurethane containing hydrogen bonds and metal coordination bonds, which is component A.

[0078] (4) Synthesis of high-strength, high-toughness, and aging-resistant two-component polyurethane: By weight, 1 part of hydroxyl-terminated polyurethane (component A) containing hydrogen bonds and metal coordination bonds obtained in step (3) is mixed with 1.2 parts of component B (fluorine-containing segment modified isocyanate curing agent) and stirred evenly. 2 parts of butyl acetate are diluted, placed in a tetrafluoroethylene mold to evaporate the solvent and form a film. The film is then heated and cured to remove the solvent, thus obtaining a high-strength, high-toughness, and aging-resistant two-component polyurethane.

[0079] Example 8

[0080] (1) Synthesis of isocyanate-terminated polyurethane prepolymer: 20 parts of 1,4-cyclohexane diisocyanate cyanate and 2 parts of succinic acid dihydrazide chain extender were dissolved in 35 parts of butyl acetate and 25 parts of N,N-dimethylformamide, respectively. The isophthalic acid dihydrazide chain extender dissolved in N,N-dimethylformamide was added dropwise to the dicyclohexylmethane diisocyanate solution dissolved in butyl acetate. The reaction was carried out at 70°C for 2 h in the presence of 0.3 parts of organotin catalyst to obtain aliphatic isocyanate-terminated polyurethane prepolymer.

[0081] (2) Synthesis of hydroxyl-terminated polyurethane: By weight, 0.5 parts of organotin catalyst were added to the above reaction system, and 100 parts of polycarbonate polyol that had been pre-treated by heating to remove water at 110℃ and 3 parts of trimethylolpropane were added to the above reaction system of isocyanate-terminated polyurethane prepolymer. The reaction was carried out at 90℃ for 3 hours to obtain hydroxyl-terminated polyurethane.

[0082] (3) Synthesis of hydroxyl-terminated polyurethane containing hydrogen bonds and metal coordination bonds: Take 0.5 parts of Zn(CF3SO3)2 crosslinking agent and dissolve it in 10 parts of acetonitrile. Add it to the hydroxyl-terminated polyurethane obtained in step (2) and stir to mix evenly to obtain hydroxyl-terminated polyurethane containing hydrogen bonds and metal coordination bonds, which is component A.

[0083] (4) Synthesis of high-strength, high-toughness, and aging-resistant two-component polyurethane: By weight, 1 part of hydroxyl-terminated polyurethane (component A) containing hydrogen bonds and metal coordination bonds obtained in step (3) is mixed with 1.2 parts of component B (fluorine-containing segment modified isocyanate curing agent) and stirred evenly. 2 parts of butyl acetate are diluted, placed in a tetrafluoroethylene mold to evaporate the solvent and form a film. The film is then heated and cured to remove the solvent, thus obtaining a high-strength, high-toughness, and aging-resistant two-component polyurethane.

[0084] Example 9

[0085] (1) Synthesis of isocyanate-terminated polyurethane prepolymer: 20 parts of 1,4-cyclohexane diisocyanate cyanate and 8 parts of succinic dihydrazide chain extender were dissolved in 35 parts of butyl acetate and 25 parts of N,N-dimethylformamide, respectively. The isophthalic dihydrazide chain extender dissolved in N,N-dimethylformamide was added dropwise to the dicyclohexylmethane diisocyanate solution dissolved in butyl acetate. The reaction was carried out at 70°C for 2 h in the presence of 0.3 parts of organotin catalyst to obtain aliphatic isocyanate-terminated polyurethane prepolymer.

[0086] (2) Synthesis of hydroxyl-terminated polyurethane: By weight, 0.5 parts of organotin catalyst were added to the above reaction system, and 100 parts of polycarbonate polyol that had been pre-treated by heating to remove water at 110℃ and 3 parts of trimethylolpropane were added to the above reaction system of isocyanate-terminated polyurethane prepolymer. The reaction was carried out at 90℃ for 3 hours to obtain hydroxyl-terminated polyurethane.

[0087] (3) Synthesis of hydroxyl-terminated polyurethane containing hydrogen bonds and metal coordination bonds: Take 0.1 parts of Zn(CF3SO3)2 crosslinking agent and dissolve it in 10 parts of acetonitrile. Add it to the hydroxyl-terminated polyurethane obtained in step (2) and stir to mix evenly to obtain hydroxyl-terminated polyurethane containing hydrogen bonds and metal coordination bonds, which is component A.

[0088] (4) Synthesis of high-strength, high-toughness, and aging-resistant two-component polyurethane: By weight, 1 part of hydroxyl-terminated polyurethane (component A) containing hydrogen bonds and metal coordination bonds obtained in step (3) is mixed with 1.2 parts of component B (fluorine-containing segment modified isocyanate curing agent) and stirred evenly. 2 parts of butyl acetate are diluted, placed in a tetrafluoroethylene mold to evaporate the solvent and form a film. The film is then heated and cured to remove the solvent, thus obtaining a high-strength, high-toughness, and aging-resistant two-component polyurethane.

[0089] Comparative Example 1

[0090] (1) Synthesis of isocyanate-terminated polyurethane prepolymer: 20 parts of 1,4-cyclohexane diisocyanate cyanate and 2 parts of 1,4-butanediol were dissolved in 35 parts of butyl acetate and 25 parts of N,N-dimethylformamide, respectively. The 1,4-butanediol chain extender dissolved in N,N-dimethylformamide was added dropwise to the isocyanate solution dissolved in butyl acetate. The reaction was carried out at 70°C for 2 h in the presence of 0.3 parts of organotin catalyst to obtain aliphatic isocyanate-terminated polyurethane prepolymer.

[0091] (2) Synthesis of hydroxyl-terminated polyurethane: By weight, 0.5 parts of organotin catalyst were added to the above reaction system, and 100 parts of polycarbonate polyol that had been pre-treated by heating to remove water at 110℃ and 3 parts of trimethylolpropane were added to the reaction system of the above isocyanate-terminated polyurethane prepolymer. The reaction was carried out at 90℃ for 3 hours to obtain hydroxyl-terminated polyurethane;

[0092] (3) Synthesis of hydroxyl-terminated polyurethane containing hydrogen bonds and metal coordination bonds: Take 0.1 parts of Zn(CF3SO3)2 crosslinking agent and dissolve it in 10 parts of acetonitrile. Add it to the hydroxyl-terminated polyurethane obtained in step (2) and stir to mix evenly to obtain hydroxyl-terminated polyurethane containing hydrogen bonds and metal coordination bonds, which is component A.

[0093] (4) Synthesis of polyurethane containing hydrogen bonds and metal coordination bonds: 1 part of hydroxyl-terminated polyurethane (component A) containing hydrogen bonds and metal coordination bonds obtained in step (3) is mixed with 1.2 parts of component B (fluorine-containing segment modified isocyanate curing agent) and stirred evenly. 2 parts of butyl acetate are diluted and placed in a tetrafluoroethylene mold to evaporate the solvent and form a film. The solvent is removed by heating and curing to obtain a two-component polyurethane.

[0094] Comparative Example 2

[0095] (1) Synthesis of isocyanate-terminated polyurethane prepolymer: 20 parts of 1,4-cyclohexane diisocyanate cyanate and 2 parts of 1,6-hexanediol were dissolved in 35 parts of butyl acetate and 25 parts of N,N-dimethylformamide, respectively. The 1,6-hexanediol chain extender dissolved in N,N-dimethylformamide was added dropwise to the isocyanate solution dissolved in butyl acetate. The reaction was carried out at 70°C for 2 h in the presence of 0.3 parts of organotin catalyst to obtain aliphatic isocyanate-terminated polyurethane prepolymer.

[0096] (2) Synthesis of hydroxyl-terminated polyurethane: By weight, 0.5 parts of organotin catalyst were added to the above reaction system, and 100 parts of polycarbonate polyol that had been pre-treated by heating to remove water at 110℃ and 3 parts of trimethylolpropane were added to the reaction system of the above isocyanate-terminated polyurethane prepolymer. The reaction was carried out at 90℃ for 3 hours to obtain hydroxyl-terminated polyurethane;

[0097] (3) Synthesis of hydroxyl-terminated polyurethane containing hydrogen bonds and metal coordination bonds: Take 0.1 parts of Zn(CF3SO3)2 crosslinking agent and dissolve it in 10 parts of acetonitrile. Add it to the hydroxyl-terminated polyurethane obtained in step (2) and stir to mix evenly to obtain hydroxyl-terminated polyurethane containing hydrogen bonds and metal coordination bonds, which is component A.

[0098] (4) Synthesis of polyurethane containing hydrogen bonds and metal coordination bonds: 1 part of hydroxyl-terminated polyurethane (component A) containing hydrogen bonds and metal coordination bonds obtained in step (3) is mixed with 1.2 parts of component B (fluorine-containing segment modified isocyanate curing agent) and stirred evenly. 2 parts of butyl acetate are diluted and placed in a tetrafluoroethylene mold to evaporate the solvent and form a film. The solvent is removed by heating and curing to obtain a two-component polyurethane.

[0099] Comparative Example 3

[0100] (1) Synthesis of isocyanate-terminated polyurethane prepolymer: 20 parts of 1,4-cyclohexane diisocyanate cyanate and 2 parts of 1,4-butanediol were dissolved in 35 parts of butyl acetate and 25 parts of N,N-dimethylformamide, respectively. The 1,4-butanediol chain extender dissolved in N,N-dimethylformamide was added dropwise to the isocyanate solution dissolved in butyl acetate. The reaction was carried out at 70°C for 2 h in the presence of 0.3 parts of organotin catalyst to obtain aliphatic isocyanate-terminated polyurethane prepolymer.

[0101] (2) Synthesis of hydroxyl-terminated polyurethane: By weight, 0.5 parts of organotin catalyst were added to the above reaction system, and 100 parts of polycarbonate polyol that had been pre-treated by heating to remove water at 110℃ and 3 parts of trimethylolpropane were added to the above reaction system of isocyanate-terminated polyurethane prepolymer. The reaction was carried out at 90℃ for 3 hours to obtain hydroxyl-terminated polyurethane, which is component A;

[0102] (3) Synthesis of two-component polyurethane: 1 part of hydroxyl-terminated polyurethane (component A) obtained in step (2) is mixed with 1.2 parts of component B (fluorine-containing segment modified isocyanate curing agent) and stirred evenly. 2 parts of butyl acetate are diluted and placed in a tetrafluoroethylene mold to evaporate the solvent and form a film. The solvent is removed by heating and curing to obtain two-component polyurethane.

[0103] Comparative Example 4

[0104] (1) Synthesis of isocyanate-terminated polyurethane prepolymer: 20 parts of 1,4-cyclohexane diisocyanate cyanate and 20 parts of succinic dihydrazide chain extender were dissolved in 35 parts of butyl acetate and 25 parts of N,N-dimethylformamide, respectively. The isophthalic dihydrazide chain extender dissolved in N,N-dimethylformamide was added dropwise to the dicyclohexylmethane diisocyanate solution dissolved in butyl acetate. The reaction was carried out at 70°C for 2 h in the presence of 0.3 parts of organotin catalyst to obtain aliphatic isocyanate-terminated polyurethane prepolymer.

[0105] (2) Synthesis of hydroxyl-terminated polyurethane: By weight, 0.5 parts of organotin catalyst were added to the above reaction system, and 100 parts of polycarbonate polyol that had been pre-treated by heating to remove water at 110℃ and 3 parts of trimethylolpropane were added to the above reaction system of isocyanate-terminated polyurethane prepolymer. The reaction was carried out at 90℃ for 3 hours to obtain hydroxyl-terminated polyurethane.

[0106] (3) Synthesis of hydroxyl-terminated polyurethane containing hydrogen bonds and metal coordination bonds: Take 0.1 parts of Zn(CF3SO3)2 crosslinking agent and dissolve it in 10 parts of acetonitrile. Add it to the hydroxyl-terminated polyurethane obtained in step (2) and stir to mix evenly to obtain hydroxyl-terminated polyurethane containing hydrogen bonds and metal coordination bonds, which is component A.

[0107] (4) Synthesis of polyurethane containing hydrogen bonds and metal coordination bonds: By weight, 1 part of hydroxyl-terminated polyurethane (component A) containing hydrogen bonds and metal coordination bonds obtained in step (3) is mixed with 1.2 parts of component B (fluorine-containing segment modified isocyanate curing agent) and stirred evenly. 2 parts of butyl acetate are diluted, placed in a tetrafluoroethylene mold to evaporate the solvent and form a film. The film is then heated to cure and remove the solvent to obtain a two-component polyurethane.

[0108] Comparative Example 5

[0109] (1) Synthesis of isocyanate-terminated polyurethane prepolymer: 20 parts of 1,4-cyclohexane diisocyanate cyanate and 2 parts of succinic acid dihydrazide chain extender were dissolved in 35 parts of propylene glycol methyl ether acetate and 25 parts of N,N-dimethylacetamide, respectively. The succinic acid dihydrazide chain extender dissolved in N,N-dimethylacetamide was added dropwise to the isocyanate solution dissolved in propylene glycol methyl ether acetate, and the reaction was carried out at 70°C for 2 h in the presence of 0.3 parts of organotin catalyst to obtain aliphatic isocyanate-terminated polyurethane prepolymer;

[0110] (2) Synthesis of hydroxyl-terminated polyurethane: By weight, 0.5 parts of organotin catalyst were added to the above reaction system, and 100 parts of polycarbonate polyol that had been pre-treated by heating to remove water at 110℃ and 3 parts of trimethylolpropane were added to the above reaction system of isocyanate-terminated polyurethane prepolymer. The reaction was carried out at 90℃ for 3 hours to obtain hydroxyl-terminated polyurethane, which is component A;

[0111] (3) Synthesis of two-component polyurethane: By weight, 1 part of hydrogen-bonded hydroxyl-terminated polyurethane (component A) obtained in step (2) is mixed with 1.2 parts of component B (fluorine-containing segment modified isocyanate curing agent) and stirred evenly. 2 parts of propylene glycol methyl ether acetate are diluted and placed in a tetrafluoroethylene mold to evaporate the solvent and form a film. The film is then heated and cured to remove the solvent, resulting in a high-strength, high-toughness and aging-resistant two-component polyurethane.

[0112] Mechanical properties of the two-component polyurethane films obtained in Examples 1-9 and Comparative Examples 1-5 were tested. Tensile strength and elongation at break were tested according to the methods in GB / T 528-2009, "Determination of Tensile Stress-Strain Properties of Vulcanized Rubber or Thermoplastic Rubber". Toughness was obtained by plotting the tensile strength and elongation at break data as a tensile strength-elongation at break curve (i.e., a stress-strain curve), and then calculating the area covered by the stress-strain curve. The test results are shown in Tables 1 and 2. Furthermore, the two-component polyurethane films obtained in Examples 1-3 were subjected to UVA testing for 7 days, followed by mechanical property testing. The test results are shown in Table 3.

[0113] Table 1. Polyurethane performance test results of Examples 1-9

[0114] Tensile strength, MPa Elongation at break, % <![CDATA[Toughness, (MJ / m 3 )]]> Example 1 56.7 922.6 318.1 Example 2 53.3 962.3 320.5 Example 3 49.3 980.3 316.3 Example 4 41.5 1004.5 304.2 Example 5 39.8 1015.7 295.3 Example 6 44.8 872.2 307.8 Example 7 41.1 829.8 303.1 Example 8 38.4 903.1 296.9 Example 9 40.3 821.6 301.4

[0115] Table 2 shows the polyurethane performance test results of Comparative Examples 1–5.

[0116] Tensile strength, MPa Elongation at break, % <![CDATA[Toughness, (MJ / m 3 )]]> Comparative Example 1 34.1 997.8 277.8 Comparative Example 2 33.6 1008.3 280.1 Comparative Example 3 24.9 1020.3 227.3 Comparative Example 4 38.2 794.4 287.7 Comparative Example 5 35.4 1232.7 285.6

[0117] Tables 1 and 2 show the performance test results of the polyurethane films obtained in Examples 1-9 and Comparative Examples 1-5, respectively. According to the results in Table 2, the tensile strength, elongation at break, and toughness of Comparative Example 3 are relatively poor. Its tensile strength is 24.9 MPa, comparable to that of commercially available two-component polyurethane materials. This is because it did not contain a metal ion crosslinking agent. Compared to Comparative Example 3, the tensile strength and toughness of Comparative Examples 1 and 2 are enhanced to some extent, while the elongation at break is slightly reduced. This is because 1,4-butanediol or 1,6-hexanediol, acting as chain extenders, can form hydrogen bonds. These hydrogen bonds can form metal ion coordination bonds with metal ions, enhancing the strength and toughness of the two-component polyurethane materials. However, comparing the specific values ​​of tensile strength, elongation at break, and toughness of Comparative Examples 1-2 and Comparative Example 3, it is found that the improvement in tensile strength and toughness of Comparative Examples 1-2 is not significant.

[0118] Compared with Comparative Examples 1-3, the polyurethane materials prepared in Examples 1-9 showed significantly enhanced strength and toughness. This is because the hydrazide groups in the system can form metal-ion coordination bonds with metal ions, further enhancing the strength and toughness of the polyurethane materials. Simultaneously, the introduction of hydrazide chain extenders introduced more hydrogen-bonding groups into the system. These hydrogen bonds can also form stronger metal-ion coordination bonds with metal ions, further enhancing the strength and toughness of the polyurethane materials. In particular, the tensile strength of Example 1 reached 56.7 MPa, far exceeding the 10-25 MPa of the prior art, solving the technical problem of insufficient film strength in the prior art. In Table 1, the toughness of Examples 1-7 and Example 9 is greater than 300 MJ / m. 3 Therefore, the two-component polyurethane obtained by this invention possesses both high strength and high toughness. However, data from Examples 6-9 show that as the amount of metal ion crosslinking agent or hydrazide chain extender increases, the resulting two-component polyurethane becomes increasingly brittle, and its mechanical properties gradually deteriorate. In particular, data from Comparative Example 4 shows that if too many hydrogen bonds of hydrazide groups are introduced into the system, it is no longer possible to achieve both high strength and high toughness. In addition, data from Comparative Example 5 shows that if only hydrogen bonds of hydrazide groups exist in the system, without metal coordination bonds, its mechanical properties are also weaker than those of the strong and tough polyurethane that possesses both metal coordination bonds and hydrogen bonds of hydrazide groups (Examples 1-9).

[0119] Table 3. Performance test results of polyurethane in Examples 1-3 after 7 days of UVA testing.

[0120] Tensile strength, MPa Elongation at break, % <![CDATA[Toughness, (MJ / m 3 )]]> Example 1 48.1 890.1 285.3 Example 2 49.2 928.4 300.4 Example 3 48.9 943.9 291.6

[0121] As shown in Table 3, the two-component polyurethanes prepared in Examples 1-3, in addition to possessing excellent tensile strength, elongation at break, and toughness, also exhibit excellent aging resistance. This is due to the synergistic effect of the aging-resistant raw materials in components A and B, which allows them to maintain excellent tensile strength and toughness even after 7 days of UVA testing. Therefore, the two-component polyurethane obtained by this invention combines high strength, high toughness, and aging resistance, meeting the protection requirements of two-component polyurethane coatings under prolonged outdoor or harsh conditions.

[0122] The polyurethane films obtained according to Examples 4-5 were subjected to fluorescence performance testing. The fluorescence performance testing method involved irradiating the polyurethane films with ultraviolet light emitted from a commercially available 254nm ultraviolet lamp. The test results are as follows: Figure 1 and Figure 2 As shown, where, Figure 1 This is a graph showing the test results of Example 4. Figure 2 This is a graph showing the test results of Example 5. According to... Figure 1 It can be seen that, in Example 4, by adding EuCl3 as a metal ion crosslinking agent, the two-component polyurethane prepared in Example 4 exhibits red fluorescence under ultraviolet light irradiation; according to Figure 2 It is evident that in Example 5, the addition of TbCl3 as a metal ion crosslinking agent resulted in the two-component polyurethane prepared in Example 5 exhibiting green fluorescence under ultraviolet light irradiation. Therefore, the two-component polyurethanes prepared in Examples 4 and 5 demonstrate fluorescent properties under ultraviolet light irradiation. This is attributed to the formation of metal ion coordination bonds between rare earth ions and hydrazide groups. The introduction of fluorescence properties expands the application possibilities of the two-component polyurethane.

[0123] In summary, the two-component polyurethane obtained by this invention not only possesses high strength, high toughness, and aging resistance, but also incorporates rare earth ions to give it fluorescent properties, making it suitable for a wide range of applications.

Claims

1. A high-strength, high-toughness, and aging-resistant two-component polyurethane, characterized in that: The two-component polyurethane comprises component A and component B; the weight ratio of component A to component B is 1:0.1 to 1.

2. Component A is prepared from raw materials comprising the following components: Each component, by weight, The structural formula of component B is as follows: The acylhydrazine chain extender is at least one of isophthalic acid dihydrazide, malonylhydrazine, succinic acid dihydrazide, adipic acid dihydrazide, and sebacate hydrazide; The A component is prepared by the following steps: (1) The aliphatic isocyanate and the hydrazide chain extender are dissolved in the first solvent and the second solvent respectively, mixed, a portion of catalyst is added, and heated to react, to obtain the aliphatic isocyanate-terminated polyurethane prepolymer; the portion of catalyst is 30-40 wt% of the total amount of catalyst in the A component. (2) Add the remaining catalyst to the aliphatic isocyanate-terminated polyurethane prepolymer of step (1), and add the oligomer polyol and the polyol small molecule crosslinking agent at 110-120°C, and heat to react to obtain hydroxyl-terminated polyurethane; (3) Add the metal ion crosslinking agent dissolved in a third solvent to the hydroxyl-terminated polyurethane of step (2) to obtain component A.

2. The high-strength, high-toughness, and aging-resistant two-component polyurethane according to claim 1, characterized in that: In component A, each component is expressed in parts by weight. 100 parts by weight of oligomeric polyol 15-25 parts by weight of aliphatic isocyanate 2-9 parts by weight of acylhydrazine chain extender 2-3 parts by weight of polyol small molecule crosslinking agent 0.2-0.5 parts by weight of metal ion crosslinking agent Catalyst 0.5 to 5 parts by weight.

3. The high-strength, high-toughness, and aging-resistant two-component polyurethane according to claim 1, characterized in that: The aliphatic isocyanate is at least one selected from isophorone diisocyanate, 1,4-cyclohexane diisocyanate, hexamethylene diisocyanate, and dicyclohexylmethane diisocyanate; and / or The catalyst is at least one of organotin catalysts, organobismuth catalysts, and tertiary amine catalysts; and / or The oligomeric polyol is at least one of polycarbonate polyol, polycaprolactone polyol, polytetrahydrofuran polyol, and hydroxyl-terminated polybutadiene; and / or The polyol small molecule crosslinking agent is trimethylolpropane; and / or The metal ion crosslinking agent is at least one of ZnCl2, Zn(CF3SO3)2, Zn(CF3COO)2, FeCl3, EuCl3, and TbCl3.

4. The high-strength, high-toughness, and aging-resistant two-component polyurethane according to claim 1, characterized in that: The weight ratio of the aliphatic isocyanate, the catalyst, and the acylhydrazine chain extender is 20:0.2-3:1.6-12.

5. The high-strength, high-toughness, and aging-resistant two-component polyurethane according to claim 1, characterized in that: The weight ratio of component A to component B is 1:0.8 to 1.

2.

6. The high-strength, high-toughness, and aging-resistant two-component polyurethane according to claim 1, characterized in that: The first solvent is at least one selected from ethyl acetate, butyl acetate, xylene, propylene glycol methyl ether acetate, butanone, and n-hexane; and / or The second solvent is at least one selected from N-methylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, isophorone, and cyclohexanone; and / or The third solvent is at least one of acetonitrile, tetrahydrofuran, propylene glycol methyl ether acetate, chloroform, N,N-dimethylformamide, and dichloromethane.

7. The high-strength, high-toughness, and aging-resistant two-component polyurethane according to claim 6, characterized in that: The mass ratio of the first solvent to the aliphatic isocyanate is 1 to 3:1; and / or The mass ratio of the second solvent to the hydrazide chain extender is 20:1 to 10; and / or The mass ratio of the third solvent to the metal ion crosslinking agent is 10:0.1-3; and / or The mass ratio of the first solvent to the catalyst is 100:0.1 to 2.

8. The high-strength, high-toughness, and aging-resistant two-component polyurethane according to claim 6, characterized in that: The mass ratio of the first solvent to the aliphatic isocyanate is 2-3:1; and / or The mass ratio of the second solvent to the acylhydrazine chain extender is 20:4-7; and / or The mass ratio of the third solvent to the metal ion crosslinking agent is 10:0.1 to 1; and / or The mass ratio of the first solvent to the catalyst is 100:0.5 to 1.

5.

9. The high-strength, high-toughness, and aging-resistant two-component polyurethane according to claim 1, characterized in that: In step (1), the reaction temperature is 50–100℃; the reaction time is 0.5–4 h; and / or In step (2), the reaction temperature is 70–110℃ and the reaction time is 1–6h.

10. The high-strength, high-toughness, and aging-resistant two-component polyurethane according to claim 1, characterized in that: In step (1), the reaction temperature is 70–90°C; the reaction time is 1–2 h; and / or In step (2), the reaction temperature is 80-100℃ and the reaction time is 2-4h.

11. The method for preparing the high-strength, high-toughness, and aging-resistant two-component polyurethane as described in any one of claims 1 to 10, characterized in that... The method includes: mixing component A and component B according to the specified amounts, adding a solvent, evaporating, and heating to cure, thereby obtaining the high-strength, high-toughness, and aging-resistant two-component polyurethane; the solvent is at least one selected from ethyl acetate, butyl acetate, xylene, propylene glycol methyl ether acetate, butanone, and n-hexane.

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