Waterborne polyurethane elastomer material with super-strong mechanical property as well as preparation method and application of waterborne polyurethane elastomer material

Abstract

The invention provides a waterborne polyurethane elastomer material with super-strong mechanical properties as well as a preparation method and application of the waterborne polyurethane elastomer material. The preparation method comprises the following steps: firstly, introducing an inactive dihydric alcohol reinforced chain extender into a macromolecular chain, and then introducing an active diamine or dihydrazide chain extender to prepare the waterborne polyurethane. According to the method, more hydrogen bonds and a mismatched structure formed by two supramolecular chain extenders are introduced, so that the energy dissipation capacity of the material is remarkably enhanced, and the mechanical property of the waterborne polyurethane elastomer is greatly improved. The method is simple and convenient to operate, high in synthesis efficiency and controllable in process, and effectively solves the problem that the mechanical property of the traditional waterborne polyurethane elastomer is reduced due to introduction of hydrophilic groups.

Description

Technical Field

[0001] This invention relates to a waterborne polyurethane elastomer material with superior mechanical properties, its preparation method, and its application, belonging to the field of elastomer material preparation technology. Background Technology

[0002] Waterborne polyurethane elastomers, with their low environmental risks, excellent mechanical properties, and broad compatibility, play an irreplaceable role in modern manufacturing and consumer products—especially in energy-saving, green, and sustainable fields. As the technology matures and environmental regulations become more stringent, the application prospects of waterborne polyurethanes will be even broader, and they are expected to become a core pillar of future high-performance, low-carbon, and recyclable material systems.

[0003] However, during the synthesis of waterborne polyurethane elastomers, the hydrophilic groups introduced to achieve water dispersibility often disrupt the regularity and integrity of the hard segment phase. Coupled with inherent defects in its particle film-forming mechanism, this often results in insufficient strength and toughness on a macroscopic scale, limiting its application in high-end fields. These deficiencies in mechanical properties make the products more prone to crack propagation, fatigue accumulation, and accelerated external damage during actual use, significantly shortening their service life and ultimately leading to reduced resource utilization efficiency and unnecessary waste.

[0004] Therefore, how to design waterborne polyurethane materials with excellent mechanical properties remains an urgent problem to be solved. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a waterborne polyurethane elastomer material with superior mechanical properties, its preparation method, and its applications.

[0006] This invention successfully constructs a strong and tough waterborne polyurethane elastomer by introducing a mismatched supramolecular chain extender containing high-density hydrogen bonds into the polymer chain. This significantly improves the mechanical properties of the waterborne polyurethane elastomer, which are significantly better than those of conventional products and have excellent prospects for practical applications.

[0007] The technical solution of the present invention is as follows: A method for preparing a waterborne polyurethane elastomer material with superior mechanical properties includes the following steps: (1) Mix the diol, diisocyanate, hydrophilic chain extender and catalyst evenly, and heat to react to obtain phase A; (2) Add a diol chain extender to the organic solvent and mix well to obtain phase B; (3) Add phase B to phase A, mix well, heat to react, and cool to room temperature to obtain phase C; (4) Add triethylamine neutralizing agent to phase C, stir the reaction to obtain phase D; (5) Add diamine chain extender or dihydrazide chain extender to ultrapure water and mix evenly to obtain phase E; (6) Add phase D to phase E, stir to react, degas under vacuum, and dry to obtain waterborne polyurethane elastomer.

[0008] According to a preferred embodiment of the present invention, in step (1), the selected diol has an average molecular weight of 1000 to 3000 g / mol and is selected from one or more of polytetrahydrofuran (PTMEG), polycaprolactone (PCL), polybutylene adipate (PBA), and polycarbonate (PCDL).

[0009] According to a preferred embodiment of the present invention, in step (1), the selected diisocyanate is selected from one or a mixture of two or more of 4,4'-dicyclohexylmethane diisocyanate (HMDI), diphenylmethane-4,4'-diisocyanate (MDI), isophorone diisocyanate (IPDI), toluene diisocyanate (TDI) and hexamethylene diisocyanate (HDI).

[0010] According to a preferred embodiment of the present invention, in step (1), the hydrophilic chain extender is one or a mixture of two or more of dimethylolpropionic acid (DMPA), dimethylolbutyric acid (DMBA), sodium ethylenediamine ethanesulfonate and sodium 1,4-butanediol-2-sulfonate.

[0011] According to a preferred embodiment of the present invention, the catalyst selected in step (1) is selected from one or more of dibutyltin dilaurate (DBTDL), bismuth laurate, stannous octoate or bismuth isooctanoate.

[0012] According to a preferred embodiment of the present invention, in step (1), the molar ratio of the diol to the diisocyanate is (0.25-2):1.

[0013] According to a preferred embodiment of the present invention, in step (1), the molar ratio of the hydrophilic chain extender to the diisocyanate is (0.20-2):1.

[0014] According to a preferred embodiment of the present invention, in step (1), the molar ratio of catalyst to diisocyanate is (0.002-0.05):1.

[0015] According to a preferred embodiment of the present invention, in step (1), the temperature of the heating reaction is 60-80°C and the reaction time is 2-4 hours.

[0016] According to a preferred embodiment of the present invention, in step (2), the diol chain extender is one or a mixture of two or more of 1,3-propanediol (PDO), 1,4-butanediol (BDO), 1,6-hexanediol (HDO) and N,N-bis(2-hydroxyethyl)oxalamide (BHO).

[0017] According to a preferred embodiment of the present invention, in step (2), the molar ratio of the amount of the diol chain extender to the diisocyanate is (0.05-1):1.

[0018] According to a preferred embodiment of the present invention, in step (2), the organic solvent is acetone.

[0019] According to a preferred embodiment of the present invention, in step (2), the mass-volume ratio of the diol chain extender to the organic solvent is (0.05-0.5):(10-50), unit, g / mL.

[0020] According to a preferred embodiment of the present invention, in step (3), the temperature of the heating reaction is 45-60°C and the reaction time is 2-3 hours.

[0021] According to a preferred embodiment of the present invention, in step (4), the molar ratio of the triethylamine neutralizing agent to the hydrophilic chain extender in step (1) is (0.9-1):1.

[0022] According to a preferred embodiment of the present invention, in step (4), the stirring reaction is carried out at 200-400 r / min for 0.1-1 h.

[0023] According to a preferred embodiment of the present invention, in step (5), the dihydrazide chain extender is adipic dihydrazide (ADH), carbamate dihydrazide (CHZ), maleic dihydrazide (MDH), or oxalate dihydrazide (ODH).

[0024] According to a preferred embodiment of the present invention, in step (5), the diamine chain extender is 1,5-diaminopentane (PDA), 1,6-diaminohexane (HMDA), 1,3-diaminopropane (DAP), p-phenylenediamine (PPD), or triethylenetetramine (TETA).

[0025] According to a preferred embodiment of the present invention, in step (5), the molar ratio of the diamine chain extender or dihydrazide chain extender to the diisocyanate in step (1) is (0.1-2):1.

[0026] According to a preferred embodiment of the present invention, in step (6), the stirring reaction is carried out at 1000-2000 r / min for 10-15 h.

[0027] According to a preferred embodiment of the present invention, in step (6), the drying temperature is 60-80°C and the reaction time is 24-72 h.

[0028] A waterborne polyurethane elastomer material with superior mechanical properties was prepared using the method described above.

[0029] The above-mentioned waterborne polyurethane elastomer materials with superior mechanical properties are used in electromagnetic device shielding materials, flexible actuators, and biomedical materials.

[0030] The aforementioned waterborne polyurethane elastomer materials with superior mechanical properties are used in leather finishing, waterproof and breathable fabrics, or in the fabrication of sensors by combining them with conductive particles. The conductive particles are Mxene or carbon nanotubes.

[0031] The beneficial effects of this invention are as follows: 1. Compared with traditional methods for synthesizing single-strength chain extenders, this invention first introduces an inert diol-strength chain extender into the polymer chain, followed by the introduction of an active diamine or dihydrazide chain extender to prepare waterborne polyurethane. This method significantly enhances the energy dissipation capacity of the material by introducing more hydrogen bonds and the mismatch structure formed by the two supramolecular chain extenders, thereby greatly improving the mechanical properties of the waterborne polyurethane elastomer. This method is simple to operate, has high synthesis efficiency, and is process-controllable, effectively solving the problem of decreased mechanical properties in traditional waterborne polyurethane elastomers due to the introduction of hydrophilic groups.

[0032] 2. The waterborne polyurethane elastomer prepared by this invention has good toughness and strength. Attached Figure Description

[0033] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0034] Figure 1 The Fourier transform infrared (FTIR) spectrum of the elastomer material prepared in Example 1 of this invention; Figure 2 This is a comparison diagram of the particle size of the elastomer materials prepared in Example 1 and Comparative Example 2.

[0035] Figure 3 A comparison diagram of the toughness of the elastomer materials prepared in Example 1 and Comparative Example 1; Figure 4 This is a comparison diagram of the puncture resistance of the elastomer materials prepared in Example 2 and Comparative Example 3; Figure 5 Comparison of stress-strain tests on the elastomer materials prepared in Example 4 and Comparative Example 4; Figure 6 This is a comparison diagram of the strength of the elastomer materials prepared in Example 4 and Comparative Example 5; Detailed Implementation

[0036] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0037] The present invention will be further described in detail below with reference to specific embodiments. It should be noted that the specific embodiments are explanations of the present invention and not limitations thereof.

[0038] Example 1: The preparation method of waterborne polyurethane elastomer materials with superior mechanical properties includes the following steps: (1) Add 9g of polytetrahydrofuran PTMEG and 4g of isophorone diisocyanate IPDI, 50μL of dibutyltin dilaurate DBTDL catalyst, and 0.9g of dimethylolbutyric acid DMBA to a 250mL three-necked flask, heat to 75℃, stir and react for 3h to obtain phase A prepolymer. (2) Cool down to 50℃, add 0.18g of 1,4-butanediol BDO to 20mL of acetone, mix well to obtain phase B; (3) Add phase B to phase A, mix well, and react at 50°C for 3 hours to obtain phase C; (4) After the reaction temperature drops to 25℃, 0.6g of triethylamine neutralizing agent is added to phase C, and the reaction is stirred at 300r / min for 0.5h to obtain phase D; (5) Add 0.44g of adipic acid dihydrazide (ADH) to 38g of ultrapure water and mix well to obtain phase E; (6) Add phase D to phase E, stir and react at 1500 r / min for 12 h, degas under vacuum, and dry at 60 °C for 48 h to obtain waterborne polyurethane elastomer.

[0039] The FTIR spectrum of the waterborne polyurethane elastomer prepared in this embodiment is as follows: Figure 1 As shown, by Figure 1 It can be seen that the fluorescent elastomer prepared in this embodiment has a fluorescence density of 1715 cm⁻¹. -1 A C=O peak is present, and it is at 2260 cm⁻¹. -1 The absence of a peak at N=C=O confirms the successful synthesis of the fluorescent elastomer.

[0040] Example 2: The preparation method of waterborne polyurethane elastomer materials with superior mechanical properties includes the following steps: (1) Add 9g of polycaprolactone PCL and 4.7g of 4,4'-dicyclohexylmethane diisocyanate HMDI, 50μL of dibutyltin dilaurate (DBTDL) catalyst, and 0.8g of hydrophilic chain extender dimethylolpropionic acid (DMPA) to a 250mL three-necked flask, heat to 75℃, stir and react for 3h to obtain phase A; (2) Cool down to 50℃, add 0.18g of 1,4-butanediol (BDO) to 20mL of acetone, mix well to obtain phase B; (3) Add phase B to phase A, mix well, and react at 50°C for 3 hours to obtain phase C; (4) After the reaction temperature drops to 25℃, 0.6g of triethylamine neutralizing agent is added to phase C, and the reaction is stirred at 300r / min for 0.5h to obtain phase D; (5) Add 0.22 g of carbazide (CHZ) to 38 g of ultrapure water and mix well to obtain phase E; (6) Add phase D to phase E, stir and react at 1500 r / min for 12 h, degas under vacuum, and dry at 60 °C for 48 h to obtain waterborne polyurethane elastomer.

[0041] Example 3: The preparation method of waterborne polyurethane elastomer materials with superior mechanical properties includes the following steps: (1) Add 9g of polybutylene adipate (PBA) and 4.5g of diphenylmethane-4,4'-diisocyanate (MDI), 50μL of dibutyltin dilaurate (DBTDL) catalyst, and 0.8g of dimethylolpropionic acid (DMPA) hydrophilic chain extender to a 250mL three-necked flask, heat to 75℃, stir and react for 3h to obtain phase A; (2) Cool down to 50℃, add 0.15g of 1,3-propanediol (PDO) to 20mL of acetone, mix well to obtain phase B; (3) Add phase B to phase A, mix well, and react at 50°C for 3 hours to obtain phase C; (4) After the reaction temperature was lowered to 25℃, 0.6g of triethylamine neutralizing agent was added to phase C. The reaction was stirred at 300r / min for 0.5h to obtain phase D; (5) Add 0.185 g of 1,3-diaminopropane (DAP) to 38 g of ultrapure water and mix well to obtain phase E; (6) Add phase D to phase E, stir and react at 1500 r / min for 12 h, degas under vacuum, and dry at 60℃ for 48 h to obtain waterborne polyurethane elastomer.

[0042] Example 4: The preparation method of waterborne polyurethane elastomer materials with superior mechanical properties includes the following steps: (1) Add 9g of polycaprolactone (PCL) and 3g of hexamethylene diisocyanate (HDI) to a 250mL three-necked flask, add 50μL of dibutyltin dilaurate (DBTDL) catalyst and 0.9g of dimethylolbutyric acid (DMBA), heat to 75℃, stir and react for 3h to obtain phase A; (2) Cool down to 50℃, add 0.24g of 1,6-hexanediol (HDO) to 20mL of acetone, mix well to obtain phase B; (3) Add phase B to phase A, mix well, and react at 50°C for 3 hours to obtain phase C; (4) After the reaction temperature is lowered to 25℃, 0.6g of triethylamine neutralizing agent is added to phase C, and the mixture is stirred at 300r / min for 0.5h to obtain phase D. (5) Add 0.33g maleic dihydrazide (MDH) to 38g of ultrapure water and mix well to obtain phase E; (6) Add phase D to phase E, stir and react at 1500 r / min for 12 h, degas under vacuum, and dry at 60℃ for 48 h to obtain waterborne polyurethane elastomer.

[0043] Example 5: The preparation method of waterborne polyurethane elastomer materials with superior mechanical properties includes the following steps: (1) Add 9g of polytetrahydrofuran (PTMEG) and 3.13g of toluene diisocyanate (TDI) to a 250mL three-necked flask, add 50μL of dibutyltin dilaurate (DBTDL) catalyst and 0.8g of dimethylolpropionic acid (DMPA), heat to 75℃, stir and react for 3h to obtain phase A; (2) Cool down to 50℃, add 0.18g of 1,4-butanediol (BDO) to 20mL of acetone, mix well to obtain phase B; (3) Add phase B to phase A, mix well, and react at 50°C for 3 hours to obtain phase C; (4) After the reaction temperature drops to 25℃, 0.6g of triethylamine neutralizing agent is added to phase C, and the reaction is stirred at 300 r / min for 0.5h to obtain phase D; (5) Add 0.29 g of 1,6-diaminohexane (HMDA) to 38 g of ultrapure water and mix well to obtain phase E; (6) Add phase D to phase E, stir and react at 1500 r / min for 12 h, degas under vacuum, and dry at 60℃ for 48 h to obtain waterborne polyurethane elastomer.

[0044] Comparative Example 1: A method for preparing an aqueous polyurethane elastomer material, comprising the following steps: (1) Add 9g of polytetrahydrofuran PTMEG and 4g of isophorone diisocyanate IPDI, 50μL of dibutyltin dilaurate DBTDL catalyst, and 0.9g of dimethylolbutyric acid DMBA to a 250mL three-necked flask, heat to 75℃, stir and react for 3h to obtain phase A prepolymer. (2) Cool down to 50℃, add 0.53g of 1,6-hexanediol (HDO) to 20 ml of acetone, mix well to obtain phase B; (3) Add phase B to phase A, mix well, and react at 50°C for 3 hours to obtain phase C; (4) After the reaction temperature is lowered to 25℃, 0.6g of triethylamine neutralizing agent is added to phase C. The reaction is stirred at 300 r / min for 0.5h to obtain phase D.

[0045] (5) Add 38g of ultrapure water to the D phase, stir and react at 1500r / min for 12h, degas under vacuum, and dry at 60℃ for 48h to obtain waterborne polyurethane elastomer.

[0046] Comparative Example 2: A method for preparing an aqueous polyurethane elastomer material, comprising the following steps: (1) Add 9g of polytetrahydrofuran PTMEG and 4g of isophorone diisocyanate IPDI, 50μL of dibutyltin dilaurate DBTDL catalyst, and 0.9g of dimethylolbutyric acid DMBA to a 250mL three-necked flask, heat to 75℃, stir and react for 3h to obtain phase A prepolymer. (2) Cool down to 50°C, add 0.4g of 1,6-hexanediol (HDO) to 20 ml of acetone, mix well, and obtain phase B; (3) Add phase B to phase A, mix well, and react at 50°C for 3 hours to obtain phase C; (4) After the reaction temperature drops to 25°C, 0.6 g of triethylamine neutralizing agent is added to phase C, and the reaction is stirred at 300 r / min for 0.5 h to obtain phase D.

[0047] (5) Add 38g of ultrapure water to the D phase, stir and react at 1500r / min for 12h, degas under vacuum, and dry at 60℃ for 48h to obtain waterborne polyurethane elastomer.

[0048] Comparative Example 3: A method for preparing an aqueous polyurethane elastomer material, comprising the following steps: (1) Add 9g of polycaprolactone (PCL) and 4.7g of 4,4'-dicyclohexylmethane diisocyanate (HMDI) to a 250mL three-necked flask, 50μL of dibutyltin dilaurate (DBTDL) catalyst, and 0.9g of dimethylolbutyric acid (DMBA). Heat to 75℃ and stir for 3h to obtain phase A; (2) Add 20 mL of acetone to phase A, mix well, and react at 50 °C for 3 h to obtain phase B; (3) After the reaction temperature drops to 25℃, 0.6 g of triethylamine neutralizing agent is added to phase B, and the reaction is stirred at 300 r / min for 0.5 h to obtain phase C; (4) Add 0.33 g of 1,3-diaminopropane (DAP) to 38 g of ultrapure water and mix well to obtain phase D; (5) Add phase C to phase D, stir and react at 1500 r / min for 12 h, degas under vacuum, and dry at 60℃ for 48 h to obtain waterborne polyurethane elastomer.

[0049] Comparative Example 4: A method for preparing an aqueous polyurethane elastomer material, comprising the following steps: (1) Add 9g of polycaprolactone (PCL) and 3g of hexamethylene diisocyanate (HDI) to a 250mL three-necked flask, 50μL of dibutyltin dilaurate (DBTDL) catalyst, and 0.9g of dimethylolbutyric acid (DMBA). Heat to 75℃ and stir for 3h to obtain phase A; (2) Add 20 mL of acetone to phase A, mix well, and react at 50 °C for 3 h to obtain phase B; (3) After the reaction temperature drops to 25℃, 0.6g of triethylamine neutralizing agent is added to phase B, and the reaction is stirred at 300r / min for 0.5h to obtain phase C; (4) Add 0.59g of adipic acid dihydrazide (ADH) to 38g of ultrapure water and mix well to obtain phase D; (5) Add phase C to phase D, stir and react at 1500 r / min for 12 h, degas under vacuum, and dry at 60 °C for 48 h to obtain waterborne polyurethane elastomer.

[0050] Comparative Example 5: A method for preparing an aqueous polyurethane elastomer material, comprising the following steps: 1) Add 9g of polycaprolactone (PCL) and 3g of hexamethylene diisocyanate (HDI) to a 250mL three-necked flask, along with 50μL of dibutyltin dilaurate (DBTDL) catalyst and 0.9g of dimethylolbutyric acid (DMBA). Heat to 75℃ and stir for 3h to obtain phase A. (3) Add 20 mL of acetone to phase A, mix well, and react at 50 °C for 3 h to obtain phase B; (4) After the reaction temperature drops to 25℃, 0.6g of triethylamine neutralizing agent is added to phase B, and the reaction is stirred at 300r / min for 0.5h to obtain phase C; (5) Add 0.59g of dioxalic acid hydrazide (ODH) to 38g of ultrapure water and mix well to obtain phase D; (6) Add phase C to phase D, stir and react at 1500 r / min for 12 h, degas under vacuum, and dry at 60℃ for 48 h to obtain waterborne polyurethane elastomer.

[0051] Test case 1. The infrared test results of Example 1 were performed using a Fourier transform infrared spectrometer as follows: Figure 1 As shown.

[0052] Depend on Figure 1 It can be seen that the waterborne polyurethane elastomer prepared in Example 1 has a temperature of 2262 cm⁻¹. -1 The absence of peaks fully reflects that the NC=O group has completely reacted, indicating the successful synthesis of the material.

[0053] 2. The average particle size of the aqueous dispersions of Example 1 and Comparative Example 2 was determined using a nanoparticle size analyzer. The test results are as follows: Figure 2 As shown, by Figure 2 It can be seen that the average particle size of both dispersions is in the nanometer range and exhibits a unimodal distribution.

[0054] 3. The tensile strength, toughness, puncture resistance, and other mechanical properties of the elastomer materials prepared in Examples 1-5 and Comparative Examples 1-5 were tested using a universal tensile testing machine. The test results are shown in Tables 1 and 2. Table 1 Mechanical property testing Table 2 Mechanical property tests The test results show that, in Comparative Examples 1 and 2, which only added diol-reinforcing chain extenders, the mechanical properties were all lower than those of the elastomer materials prepared in the embodiments of this invention (such as...). Figure 3 As shown in the figure, this is because the hydrogen bond content of the diol chain extender is still low, which has a weak effect on improving the regularity and integrity of the hard segment phase and cannot significantly improve the mechanical properties of the material.

[0055] Compared with Comparative Examples 3-5 (which only added diamines or dihydrazides to enhance chain extenders), the mechanical properties of the prepared elastomer materials were improved compared with Comparative Examples 1-2, but were still lower than those of the materials prepared in the embodiments of the present invention. Figures 4-6 This is because while introducing only diamines or dihydrazides can introduce more hydrogen bonds and improve the regularity and integrity of the hard segment phase, the effect is limited. However, this invention employs a dual-reinforcing chain extender (a combination of a diol and a diamine or dihydrazide), which not only further enhances the regularity of the hard segment phase and the degree of microphase separation in the material, thus allowing it to withstand greater stress during stretching and improving the tensile strength of the material, its supramolecular segments can also form polymers with extremely low binding energy. During stretching, these polymers preferentially slide, effectively dissipating energy, thereby significantly improving the material's extensibility and toughness.

Claims

1. A method for preparing a waterborne polyurethane elastomer material with superior mechanical properties, comprising the following steps: (1) Mix the diol, diisocyanate, hydrophilic chain extender and catalyst evenly, and heat to react to obtain phase A; (2) Add a diol chain extender to the organic solvent and mix well to obtain phase B; (3) Add phase B to phase A, mix well, heat to react, and cool to room temperature to obtain phase C; (4) Add triethylamine neutralizing agent to phase C, stir the reaction to obtain phase D; (5) Add diamine chain extender or dihydrazide chain extender to ultrapure water and mix evenly to obtain phase E; (6) Add phase D to phase E, stir to react, degas under vacuum, and dry to obtain waterborne polyurethane elastomer.

2. The preparation method according to claim 1, characterized in that, In step (1), the selected diol has an average molecular weight of 1000-3000 g / mol and is selected from one or more of polytetrahydrofuran (PTMEG), polycaprolactone (PCL), polybutylene adipate (PBA), and polycarbonate (PCDL). The selected diisocyanate is selected from one or more of 4,4'-dicyclohexylmethane diisocyanate (HMDI), diphenylmethane-4,4'-diisocyanate (MDI), isophorone diisocyanate (IPDI), toluene diisocyanate (TDI), and hexamethylene diisocyanate (HDI). The hydrophilic chain extender is one or more of dimethylolpropionic acid (DMPA), dimethylolbutyric acid (DMBA), sodium ethylenediamine ethanesulfonate, and sodium 1,4-butanediol-2-sulfonate. The selected catalyst is selected from one or more of dibutyltin dilaurate (DBTDL), bismuth laurate, stannous octoate, or bismuth isooctanoate.

3. The preparation method according to claim 1, characterized in that, In step (1), the molar ratio of the diol to the diisocyanate is (0.25-2):1, and the molar ratio of the hydrophilic chain extender to the diisocyanate is (0.20-2):

1.

4. The preparation method according to claim 1, characterized in that, In step (1), the molar ratio of catalyst to diisocyanate is (0.002~0.05):1, the heating reaction temperature is 60~80℃, and the reaction time is 2~4h.

5. The preparation method according to claim 1, characterized in that, In step (2), the diol chain extender is one or more of 1,3-propanediol (PDO), 1,4-butanediol (BDO), 1,6-hexanediol (HDO) and N,N-bis(2-hydroxyethyl)oxalamide (BHO), and the molar ratio of the amount of the diol chain extender to the diisocyanate is (0.05-1):

1.

6. The preparation method according to claim 1, characterized in that, In step (2), the organic solvent is acetone, and the mass-volume ratio of the diol chain extender to the organic solvent is (0.05-0.5):(10-50), unit: g / mL.

7. The preparation method according to claim 1, characterized in that, In step (3), the heating reaction temperature is 45-60℃ and the reaction time is 2-3h. In step (4), the molar ratio of the triethylamine neutralizer to the hydrophilic chain extender in step (1) is (0.9-1):

1. In step (4), the stirring reaction is carried out at 200-400r / min for 0.1-1h.

8. The preparation method according to claim 1, characterized in that, In step (5), the dihydrazide chain extender is adipic dihydrazide (ADH), carbamate dihydrazide (CHZ), maleic dihydrazide (MDH), or oxalate dihydrazide (ODH), and the diamine chain extender is 1,5-diaminopentane (PDA), 1,6-diaminohexane (HMDA), 1,3-diaminopropane (DAP), p-phenylenediamine (PPD), or triethylenetetramine (TETA). The molar ratio of the diamine chain extender or dihydrazide chain extender to the diisocyanate in step (1) is (0.1-2):

1. The stirring reaction is carried out at 1000-2000 r / min for 10-15 h. The drying temperature is 60-80 °C, and the reaction time is 24-72 h.

9. A waterborne polyurethane elastomer material with superior mechanical properties, prepared by any one of the methods described in claims 1-8.

10. The application of the waterborne polyurethane elastomer material with superior mechanical properties as described in claim 9 in electromagnetic device shielding materials, flexible actuators, and biomedical materials.

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