A polyether type high solid content solvent-free waterborne polyurethane emulsion, elastomer and preparation method thereof

Abstract

The application provides a polyether type high solid content solvent-free water-based polyurethane emulsion, an elastomer and a preparation method thereof; the preparation raw material of the water-based polyurethane emulsion comprises the following components in the following weight parts: polyether polyol 90-360 parts by weight, alicyclic isocyanate 180-220 parts by weight, amine catalyst 1-5 parts by weight, hydrophilic chain extender 20-40 parts by weight, organic amine alkaline neutralizer 20-40 parts by weight, small molecular weight alcohol chain extender and / or large molecular weight alcohol chain extender 19-50 parts by weight, defoaming agent 1-5 parts by weight and deionized water 700 parts by weight. The application selects reaction raw materials with solvent functions, realizes solvent-free green synthesis, and significantly reduces the emission of organic volatile substances. The prepared water-based polyurethane emulsion has the characteristics of high solid content, and the prepared water-based polyurethane elastomer has excellent mechanical properties and hydrolysis resistance.

Description

Technical Field

[0001] This invention relates to the field of polyurethane materials technology, specifically to a polyether-type high-solids-content solvent-free waterborne polyurethane emulsion, elastomer, and preparation method thereof. Background Technology

[0002] Polyurethane (PU) is a polymer material produced by the addition polymerization reaction of polyols and isocyanates. With its excellent mechanical properties, abrasion resistance, and tunable structural characteristics, PU has been widely used in coatings, footwear materials, sound insulation materials, and automotive interiors. In recent years, with increasing global environmental awareness and increasingly stringent regulations on volatile organic compound (VOC) emissions, waterborne polyurethane (WPU), using water as the dispersion medium, has significantly reduced the use of organic solvents and has become a research hotspot and mainstream development in the field of polyurethane materials.

[0003] While waterborne polyurethane boasts excellent overall performance, it still suffers from significant drawbacks: insufficient hydrolysis resistance, making it prone to degradation and failure under humid and hot environments; low solids content, which can lead to a loose film structure, reduced mechanical properties and resistance to media, and slow drying, impacting construction efficiency. Furthermore, although current waterborne polyurethane manufacturing processes have significantly reduced the amount of organic solvents used, a small amount of organic solvent is still required to dissolve reactants or control the viscosity of the reaction system.

[0004] How to further improve the solid content and hydrolysis resistance of waterborne polyurethane while reducing the amount of organic solvents used to achieve truly solvent-free synthesis is a key scientific issue and core technological challenge that is currently driving the development of waterborne polyurethane towards high performance and green technology. Summary of the Invention

[0005] To overcome the shortcomings of existing technologies, this invention provides a polyether-type high-solids-content solvent-free waterborne polyurethane emulsion, elastomer, and their preparation method. This invention selects reactants that also function as solvents, achieving solvent-free and green synthesis of the polyether-type high-solids-content solvent-free waterborne polyurethane emulsion and elastomer. The synthesis process effectively avoids the use of organic solvents, significantly reducing the emission of volatile organic compounds. The prepared waterborne polyurethane emulsion exhibits high solids content and good storage stability, while the prepared waterborne polyurethane elastomer possesses excellent mechanical properties and hydrolysis resistance.

[0006] The objective of this invention is achieved through the following technical solution: A polyether-type high-solids-content solvent-free aqueous polyurethane emulsion, wherein the raw materials for preparing the aqueous polyurethane emulsion comprise the following components in parts by weight: 90-360 parts by weight of polyether polyol, 180-220 parts by weight of alicyclic isocyanate, 1-5 parts by weight of amine catalyst, 20-40 parts by weight of hydrophilic chain extender, 20-40 parts by weight of organic amine alkaline neutralizer, 19-50 parts by weight of low molecular weight alcohol chain extender and / or high molecular weight alcohol chain extender, 1-5 parts by weight of defoamer, and 700 parts by weight of deionized water.

[0007] According to an embodiment of the present invention, the raw materials for preparing the aqueous polyurethane emulsion include the following components in parts by weight: 180-270 parts by weight of polyether polyol, 200-220 parts by weight of alicyclic isocyanate, 1-4 parts by weight of amine catalyst, 20-30 parts by weight of hydrophilic chain extender, 20-30 parts by weight of organic amine alkaline neutralizer, 25-39 parts by weight of low molecular weight alcohol chain extender and / or high molecular weight alcohol chain extender, 2-5 parts by weight of defoamer, and 700 parts by weight of deionized water.

[0008] According to an embodiment of the present invention, the raw materials for preparing the aqueous polyurethane emulsion include the following components in parts by weight: 180-190 parts by weight of polyether polyol, 200-210 parts by weight of alicyclic isocyanate, 1-2 parts by weight of amine catalyst, 20-25 parts by weight of hydrophilic chain extender, 20-25 parts by weight of organic amine alkaline neutralizer, 25-33 parts by weight of low molecular weight alcohol chain extender, 2-4 parts by weight of defoamer, and 700 parts by weight of deionized water.

[0009] According to an embodiment of the present invention, the raw materials for preparing the aqueous polyurethane emulsion include the following components in parts by weight: 180-190 parts by weight of polyether polyol, 200-210 parts by weight of alicyclic isocyanate, 1-5 parts by weight of amine catalyst, 20-25 parts by weight of hydrophilic chain extender, 20-25 parts by weight of organic amine alkaline neutralizer, 8-27 parts by weight of high molecular weight alcohol chain extender, 12-20 parts by weight of low molecular weight alcohol chain extender, 2-4 parts by weight of defoamer, and 700 parts by weight of deionized water.

[0010] According to an embodiment of the present invention, the raw materials for preparing the aqueous polyurethane emulsion include 90 parts by weight, 100 parts by weight, 150 parts by weight, 180 parts by weight, 190 parts by weight, 200 parts by weight, 250 parts by weight, 270 parts by weight, 300 parts by weight, or 360 parts by weight of polyether polyol.

[0011] According to an embodiment of the present invention, the raw materials for preparing the aqueous polyurethane emulsion include 180 parts by weight, 190 parts by weight, 200 parts by weight, 210 parts by weight, or 220 parts by weight of alicyclic isocyanate.

[0012] According to an embodiment of the present invention, the raw materials for preparing the aqueous polyurethane emulsion include 1 part by weight, 2 parts by weight, 3 parts by weight, 4 parts by weight, or 5 parts by weight of an amine catalyst.

[0013] According to an embodiment of the present invention, the raw materials for preparing the waterborne polyurethane emulsion include 20 parts by weight, 21 parts by weight, 22 parts by weight, 23 parts by weight, 24 parts by weight, 25 parts by weight, 30 parts by weight, 35 parts by weight, or 40 parts by weight of a hydrophilic chain extender.

[0014] According to an embodiment of the present invention, the raw materials for preparing the aqueous polyurethane emulsion include 20 parts by weight, 21 parts by weight, 22 parts by weight, 23 parts by weight, 24 parts by weight, 25 parts by weight, 30 parts by weight, 35 parts by weight, or 40 parts by weight of an organic amine alkaline neutralizing agent.

[0015] According to an embodiment of the present invention, the raw materials for preparing the aqueous polyurethane emulsion include 25 parts by weight, 26 parts by weight, 27 parts by weight, 28 parts by weight, 29 parts by weight, 30 parts by weight, 31 parts by weight, 32 parts by weight, or 33 parts by weight of a low molecular weight alcohol chain extender.

[0016] According to an embodiment of the present invention, the raw materials for preparing the aqueous polyurethane emulsion include 8 parts by weight, 9 parts by weight, 10 parts by weight, 12 parts by weight, 14 parts by weight, 15 parts by weight, 16 parts by weight, 17 parts by weight, 18 parts by weight, 20 parts by weight, 22 parts by weight, 24 parts by weight, 25 parts by weight, 26 parts by weight, or 27 parts by weight of a high molecular weight alcohol chain extender and 12 parts by weight, 13 parts by weight, 14 parts by weight, 15 parts by weight, 16 parts by weight, 17 parts by weight, 18 parts by weight, 19 parts by weight, or 20 parts by weight of a low molecular weight alcohol chain extender.

[0017] According to an embodiment of the present invention, the raw materials for preparing the waterborne polyurethane emulsion include 1 part by weight, 2 parts by weight, 3 parts by weight, 4 parts by weight, or 5 parts by weight of defoamer.

[0018] According to an embodiment of the present invention, the polyether polyol is selected from any one or two of polypropylene glycol or polytetrahydrofuran ether diol; the number average molecular weight of the polyether polyol is 500-2000 g / mol.

[0019] According to an embodiment of the present invention, the alicyclic isocyanate is selected from any one or two of isophorone diisocyanate and 4,4'-dicyclohexylmethane diisocyanate.

[0020] According to an embodiment of the present invention, the amine catalyst is selected from any one or more of triethylenediamine, triethanolamine, dimethylaminopropylisopropanolamine, and N,N-dimethylcyclohexylamine. The use of the amine catalyst is beneficial for maintaining the storage stability of the aqueous polyurethane emulsion. The amine catalyst has high catalytic activity that is not reduced by the presence of moisture.

[0021] According to an embodiment of the present invention, the hydrophilic chain extender is 2,2-dihydroxymethylbutyric acid.

[0022] According to an embodiment of the present invention, the organic amine basic neutralizing agent is selected from any one or more of triethylamine, diethanolamine, and N,N-dimethylethanolamine.

[0023] According to an embodiment of the present invention, the high molecular weight alcohol chain extender is selected from diethyl dimethylolmalonate.

[0024] According to an embodiment of the present invention, the low molecular weight alcohol chain extender is selected from any one or more of 1,4-butanediol, 1,6-hexanediol, ethylene glycol, diethylene glycol, glycerol, diethylene glycol, triethylene glycol, and trimethylolpropane.

[0025] In particular, by selecting a combination of high molecular weight alcohol chain extenders and low molecular weight alcohol chain extenders, the present invention significantly improves the tensile strength and elongation at break of the prepared waterborne polyurethane elastomer, while the water absorption rate of the obtained waterborne polyurethane elastomer is <11%, indicating that the prepared waterborne polyurethane elastomer has excellent mechanical properties and hydrolysis resistance.

[0026] According to an embodiment of the present invention, the defoamer is any one or two of glycerol polyoxypropylene ether and polyoxyethylene polyoxypropylene glycerol ether; the number average molecular weight of the defoamer is 3000-3600 g / mol.

[0027] According to an embodiment of the present invention, the solid content of the aqueous polyurethane emulsion is 40-45%.

[0028] In this invention, the term "solvent-free" means free of organic solvents.

[0029] The present invention also provides a method for preparing the above-mentioned polyether-type high-solids-content solvent-free aqueous polyurethane emulsion, comprising the following steps: (1) Heat the polyether polyol and vacuum it to remove the internal moisture. After cooling, introduce nitrogen gas and add alicyclic isocyanate and amine catalyst to carry out prepolymerization reaction to obtain isocyanate-terminated polyurethane prepolymer. (2) Add hydrophilic chain extender and high molecular weight alcohol chain extender to carry out chain extension reaction, and after cooling, add organic amine alkaline neutralizer to balance the pH; add low molecular weight alcohol chain extender to carry out low temperature chain extension reaction; finally add deionized water and defoamer to carry out emulsification and dispersion, and filter to prepare polyether type high solids content solvent-free waterborne polyurethane emulsion; or, (2') Add a hydrophilic chain extender to carry out the chain extension reaction, and after cooling, add an organic amine alkaline neutralizer to balance the pH; add a low molecular weight alcohol chain extender to carry out the low temperature chain extension reaction; finally add deionized water and defoamer to carry out emulsification and dispersion, and filter to prepare a polyether-type high solids content solvent-free waterborne polyurethane emulsion.

[0030] According to an embodiment of the present invention, in step (1), after heating to 100-120 °C, vacuum is applied to remove the moisture inside the polyether polyol.

[0031] According to an embodiment of the present invention, in step (1), nitrogen gas is introduced after cooling to 40-60 °C.

[0032] According to an embodiment of the present invention, in step (1), the temperature of the prepolymerization reaction is 80-90 °C and the time of the prepolymerization reaction is 1 hour.

[0033] According to an embodiment of the present invention, in steps (2) and (2'), the temperature of the chain extension reaction is 80-90°C, and the time of the chain extension reaction is 1 hour.

[0034] According to an embodiment of the present invention, in steps (2) and (2'), an organic amine alkaline neutralizing agent is added to balance the pH after cooling to 40-60 °C.

[0035] According to an embodiment of the present invention, in steps (2) and (2'), the temperature of the low-temperature chain extension reaction is 40-50 °C, and the time of the low-temperature chain extension reaction is 3 hours.

[0036] The present invention also provides a waterborne polyurethane elastomer, which is prepared by subjecting the above-mentioned waterborne polyurethane emulsion to low-temperature drying and high-temperature heat treatment.

[0037] According to an embodiment of the present invention, the low-temperature drying is drying at 40-60°C until the shape is set, and the high-temperature heat treatment is drying at 100-110°C for 4-6 hours.

[0038] According to an embodiment of the present invention, the waterborne polyurethane elastomer has a tensile strength of 29.1-38.4 MPa, an elongation at break of 430-680%, and a water absorption rate of <11%.

[0039] This invention also provides a method for preparing the above-mentioned waterborne polyurethane elastomer, the method comprising the following steps: The waterborne polyurethane emulsion was subjected to low-temperature drying and high-temperature heat treatment to prepare the waterborne polyurethane elastomer.

[0040] According to an embodiment of the present invention, the low-temperature drying is drying at 40-60°C until the shape is set, and the high-temperature heat treatment is drying at 100-110°C for 4-6 hours.

[0041] The beneficial effects of this invention are: This invention provides a polyether-type high-solids-content solvent-free waterborne polyurethane emulsion, an elastomer, and a method for their preparation. This invention utilizes reactants that also function as solvents, achieving a solvent-free, green synthesis of the polyether-type high-solids-content solvent-free waterborne polyurethane emulsion and elastomer. The synthesis process effectively avoids the use of organic solvents, significantly reducing the emission of volatile organic compounds. The prepared waterborne polyurethane emulsion exhibits high solids content and good storage stability, while the prepared waterborne polyurethane elastomer possesses excellent mechanical properties and hydrolysis resistance. Attached Figure Description

[0042] Figure 1 The images show the polyether-type high-solids-content solvent-free waterborne polyurethane emulsion samples prepared in Examples 1-3 of this invention after centrifugation at 3000 r / min for 15 min.

[0043] Figure 2 These are photographs of the polyether-type high-solids-content solvent-free waterborne polyurethane elastomer samples prepared in Examples 1-6 of this invention.

[0044] Figure 3 This is a schematic diagram of the preparation process of the polyether-type high solids content solvent-free waterborne polyurethane prepared in Examples 1-3 of the present invention.

[0045] Figure 4 This is a schematic diagram of the preparation process of the polyether-type high-solids-content solvent-free waterborne polyurethane prepared in Examples 4-6 of the present invention.

[0046] Figure 5 The Fourier transform infrared spectra of the polyether-type high-solids-content solvent-free waterborne polyurethanes prepared in Examples 1-6 of this invention are shown.

[0047] Figure 6 The mechanical properties of the polyether-type high-solids-content solvent-free waterborne polyurethane elastomers prepared in Examples 1-6 of this invention are shown in the diagram.

[0048] Figure 7 The particle size distribution diagrams are for the polyether-type high-solids-content solvent-free aqueous polyurethane emulsions prepared in Examples 1-6 of this invention. Detailed Implementation

[0049] The technical solution of the present invention will be further described in detail below with reference to specific embodiments. It should be understood that the following embodiments are merely illustrative and explanatory of the present invention, and should not be construed as limiting the scope of protection of the present invention. All technologies implemented based on the above content of the present invention are covered within the scope of protection intended by the present invention.

[0050] Unless otherwise specified, the experimental methods used in the following examples are conventional methods; unless otherwise specified, the reagents and materials used in the following examples are commercially available.

[0051] Example 1 (1) 184 parts by weight of polypropylene glycol with a molecular weight of 1000 g / mol was heated to 110 °C and vacuumed to remove internal moisture. After cooling to 50 °C, nitrogen gas was introduced. 1.8 parts by weight of triethylenediamine catalyst, 97.4 parts by weight of isophorone diisocyanate and 110 parts by weight of 4,4'-dicyclohexylmethane diisocyanate were added. The temperature was maintained at 80 °C and stirred for 1 hour. Then 23.6 parts by weight of 2,2-dihydroxymethylbutyric acid were added and the reaction was continued for 1 hour. After cooling to 40 °C, 22.6 parts by weight of triethylamine were added for neutralization for 15 min. Then 32.4 parts by weight of 1,4-butanediol were added and stirred evenly. 700 parts by weight of deionized water were slowly added and stirred for 40 min. Then 3 parts by weight of defoamer were added and stirred at 45 °C for 3 hours. After filtration, waterborne polyurethane emulsion was obtained.

[0052] (2) The waterborne polyurethane emulsion was placed in a glass dish and dried and cured at 40 °C until the weight was constant. Then the temperature was raised to 100 °C and heated for 4 hours to obtain the waterborne polyurethane elastomer.

[0053] Example 2 (1) Other operations are the same as in Example 1, except that 27 parts by weight of 1,4-butanediol are added to obtain an aqueous polyurethane emulsion.

[0054] (2) Same as in Example 1, a solvent-free waterborne polyurethane elastomer was obtained.

[0055] Example 3 (1) Other operations are the same as in Example 1, except that 25.2 parts by weight of 1,4-butanediol are added to obtain an aqueous polyurethane emulsion.

[0056] (2) Same as in Example 1, a solvent-free waterborne polyurethane elastomer was obtained.

[0057] Example 4 (1) 184 parts by weight of polypropylene glycol with a molecular weight of 1000 g / mol was heated to 110 °C and vacuumed to remove internal moisture. After cooling to 50 °C, nitrogen gas was introduced. 1.8 parts by weight of triethylenediamine catalyst, 97.4 parts by weight of isophorone diisocyanate and 110 parts by weight of 4,4'-dicyclohexylmethane diisocyanate were added. The temperature was maintained at 80 °C and stirred for 1 hour. Then 23.6 parts by weight of 2,2-dimethylolbutyric acid were added and the reaction was continued for 1 hour. Then 8.8 parts by weight of diethyl dimethylolmalonic acid were added and the reaction was continued for 1 hour. After cooling to 40 °C, 22.6 parts by weight of triethylamine were added for neutralization for 15 min. Then 19.8 parts by weight of 1,4-butanediol were added and stirred evenly. 700 parts by weight of deionized water were slowly added and stirred for 40 min. Then 3 parts by weight of defoamer were added and stirred at 45 °C for 3 hours. After filtration, waterborne polyurethane emulsion was obtained.

[0058] (2) Same as in Example 1, a waterborne polyurethane elastomer was obtained.

[0059] Example 5 (1) Other operations are the same as in Example 4, except that 17.6 parts by weight of diethyl bis(hydroxymethyl)malonate and 16.2 parts by weight of 1,4-butanediol are added to obtain an aqueous polyurethane emulsion.

[0060] (2) Same as in Example 1, a waterborne polyurethane elastomer was obtained.

[0061] Example 6 (1) Other operations are the same as in Example 1, except that 26.4 parts by weight of diethyl bis(hydroxymethyl)malonate and 12.6 parts by weight of 1,4-butanediol are added to obtain an aqueous polyurethane emulsion.

[0062] (2) Same as in Example 1, a waterborne polyurethane elastomer was obtained.

[0063] Comparative Example 1 The other operations are the same as in Example 1, except that 37.7 parts by weight of 1,4-butanediol are added to obtain an aqueous polyurethane emulsion.

[0064] The viscosity of the obtained waterborne polyurethane emulsion increased, making emulsification and dispersion more difficult. A small amount of sedimentation occurred after centrifugation, and the stability decreased.

[0065] Comparative Example 2 The other operations are the same as in Example 1, except that 19.4 parts by weight of 1,4-butanediol are added to obtain an aqueous polyurethane emulsion.

[0066] The viscosity of the obtained waterborne polyurethane emulsion was controlled, but there were a lot of unreacted isocyanates, which led to an increase in side reactions. A small amount of precipitation appeared after centrifugation of the emulsion, and the stability decreased.

[0067] Comparative Example 3 The other operations are the same as in Example 1, except that 17.6 parts by weight of 2,2-dimethylolbutyric acid are added to obtain an aqueous polyurethane emulsion. Due to the reduction in the number of hydrophilic groups introduced during the preparation process, the stability of the obtained aqueous polyurethane emulsion decreases, and obvious stratification occurs after standing overnight.

[0068] Comparative Example 4 184 parts by weight of polypropylene glycol with a molecular weight of 1000 g / mol were heated to 110 °C, and internal moisture was removed by vacuuming. After cooling to 50 °C, nitrogen gas was introduced, and 1.8 parts by weight of triethylenediamine catalyst, 97.4 parts by weight of isophorone diisocyanate, and 110 parts by weight of 4,4'-dicyclohexylmethane diisocyanate were added. The temperature was maintained at 80 °C and the mixture was stirred for 1 hour. Then, 23.6 parts by weight of 2,2-dimethylolbutyric acid were added and the reaction was continued for 1 hour. Then, 57.2 parts by weight of diethyl dimethylolmalonate were added and the reaction was continued for 1 hour. After cooling to 40 °C, 22.6 parts by weight of triethylamine were added for neutralization for 15 min. Then, 700 parts by weight of deionized water were added and the mixture was stirred for 40 min. Finally, 3 parts by weight of defoamer were added and the mixture was stirred at 45 °C for 3 hours. After filtration, an aqueous polyurethane emulsion was obtained.

[0069] The obtained waterborne polyurethane emulsion has increased viscosity, making dispersion difficult and preventing emulsification.

[0070] Table 1. Performance test results of polyether-type high-solids-content solvent-free waterborne polyurethane elastomers in Examples 1-6 and Comparative Examples 1-2

[0071] Figure 1 The images show the polyether-type high-solids-content solvent-free aqueous polyurethane emulsion samples prepared in Examples 1-3 of this invention after centrifugation at 3000 r / min for 15 min. It can be seen that the prepared aqueous polyurethane emulsions did not exhibit obvious stratification or precipitation, indicating that the prepared aqueous polyurethane emulsions possess good storage stability.

[0072] Figure 2 These are photographs of the polyether-type high-solids-content solvent-free waterborne polyurethane elastomer samples prepared in Examples 1-6 of this invention. It can be seen that the prepared waterborne polyurethane elastomers are transparent and have no obvious defects.

[0073] Figure 3 This is a schematic diagram of the preparation process of the polyether-type high solids content solvent-free waterborne polyurethane prepared in Examples 1-3 of the present invention.

[0074] Figure 4 This is a schematic diagram of the preparation process of the polyether-type high-solids-content solvent-free waterborne polyurethane prepared in Examples 4-6 of the present invention.

[0075] Figure 5 The Fourier transform infrared (FTIR) spectra of the polyether-type high-solids-content solvent-free waterborne polyurethanes prepared in Examples 1-6 of this invention are shown. It can be seen that at 2260 cm⁻¹... –1 No absorption peak of the isocyanate group was observed, indicating that the isocyanate has completely reacted.

[0076] Figure 6 The figures show the mechanical properties of the polyether-type high-solids-content solvent-free waterborne polyurethane elastomers prepared in Examples 1-6 of this invention. The mechanical properties were tested using an INSTRON 2382 electronic universal testing machine from INSTRON Corporation, USA. According to the GB / T1040.3-2006 standard, the waterborne polyurethane elastomer film was cut into dumbbell-shaped strips (50 mm × 8.5 mm) for measurement at a tensile rate of 50 mm / min. The test results show that the tensile strength of the waterborne polyurethane elastomers prepared in Examples 1-3 is 29.1-33.2 MPa, and the elongation at break is 430-530%. The tensile strength of the waterborne polyurethane elastomers prepared in Examples 4-6 is 36.0-38.4 MPa, and the elongation at break is 490-680%.

[0077] Figure 7 The particle size distribution diagrams are shown for the polyether-type high-solids-content solvent-free aqueous polyurethane emulsions prepared in Examples 1-6 of this invention. The particle size distribution was measured using a Mastersizer 3000 from Malvern Instruments, UK, for dynamic light scattering particle size analysis. The test results show that the aqueous polyurethane emulsions prepared in Examples 1-6 exhibit a unimodal particle size distribution, and the emulsions possess good stability.

[0078] The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiments. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A polyether-type high-solids-content solvent-free aqueous polyurethane emulsion, wherein, The raw materials for preparing the aqueous polyurethane emulsion include the following components in parts by weight: 90-360 parts by weight of polyether polyol, 180-220 parts by weight of alicyclic isocyanate, 1-5 parts by weight of amine catalyst, 20-40 parts by weight of hydrophilic chain extender, 20-40 parts by weight of organic amine alkaline neutralizer, 19-50 parts by weight of low molecular weight alcohol chain extender and / or high molecular weight alcohol chain extender, 1-5 parts by weight of defoamer, and 700 parts by weight of deionized water.

2. The emulsion according to claim 1, wherein, The raw materials for preparing the aqueous polyurethane emulsion include the following components in parts by weight: 180-270 parts by weight of polyether polyol, 200-220 parts by weight of alicyclic isocyanate, 1-4 parts by weight of amine catalyst, 20-30 parts by weight of hydrophilic chain extender, 20-30 parts by weight of organic amine alkaline neutralizer, 25-39 parts by weight of low molecular weight alcohol chain extender and / or high molecular weight alcohol chain extender, 2-5 parts by weight of defoamer, and 700 parts by weight of deionized water.

3. The emulsion according to claim 2, wherein, The raw materials for preparing the aqueous polyurethane emulsion include the following components in parts by weight: 180-190 parts by weight of polyether polyol, 200-210 parts by weight of alicyclic isocyanate, 1-2 parts by weight of amine catalyst, 20-25 parts by weight of hydrophilic chain extender, 20-25 parts by weight of organic amine alkaline neutralizer, 25-33 parts by weight of low molecular weight alcohol chain extender, 2-4 parts by weight of defoamer, and 700 parts by weight of deionized water.

4. The emulsion according to claim 2, wherein, The raw materials for preparing the aqueous polyurethane emulsion include the following components in parts by weight: 180-190 parts by weight of polyether polyol, 200-210 parts by weight of alicyclic isocyanate, 1-5 parts by weight of amine catalyst, 20-25 parts by weight of hydrophilic chain extender, 20-25 parts by weight of organic amine alkaline neutralizer, 8-27 parts by weight of high molecular weight alcohol chain extender, 12-20 parts by weight of low molecular weight alcohol chain extender, 2-4 parts by weight of defoamer, and 700 parts by weight of deionized water.

5. The emulsion according to claim 1, wherein, The polyether polyol is selected from any one or two of polypropylene glycol or polytetrahydrofuran ether diol; the number average molecular weight of the polyether polyol is 500-2000 g / mol. And / or, the alicyclic isocyanate is selected from any one or two of isophorone diisocyanate and 4,4'-dicyclohexylmethane diisocyanate; And / or, the amine catalyst is selected from any one or more of triethylenediamine, triethanolamine, dimethylaminopropylisopropanolamine, and N,N-dimethylcyclohexylamine; And / or, the hydrophilic chain extender is 2,2-dihydroxymethylbutyric acid; And / or, the organic amine basic neutralizing agent is selected from any one or more of triethylamine, diethanolamine, and N,N-dimethylethanolamine; And / or, the high molecular weight alcohol chain extender is selected from diethyl dimethylolmalonate; And / or, the low molecular weight alcohol chain extender is selected from any one or more of 1,4-butanediol, 1,6-hexanediol, ethylene glycol, diethylene glycol, glycerol, diethylene glycol, triethylene glycol, and trimethylolpropane; And / or, the defoamer is any one or both of glycerol polyoxypropylene ether and polyoxyethylene polyoxypropylene glycerol ether.

6. The emulsion according to any one of claims 1-5, wherein, The solid content of the waterborne polyurethane emulsion is 40-45%.

7. A method for preparing the polyether-type high-solids-content solvent-free aqueous polyurethane emulsion according to any one of claims 1-6, comprising the following steps: (1) Heat the polyether polyol and vacuum it to remove the internal moisture. After cooling, introduce nitrogen gas and add alicyclic isocyanate and amine catalyst to carry out prepolymerization reaction to obtain isocyanate-terminated polyurethane prepolymer. (2) Add hydrophilic chain extender and high molecular weight alcohol chain extender to carry out chain extension reaction, and after cooling, add organic amine alkaline neutralizer to balance the pH; add low molecular weight alcohol chain extender to carry out low temperature chain extension reaction; finally add deionized water and defoamer to carry out emulsification and dispersion, and filter to prepare polyether type high solids content solvent-free waterborne polyurethane emulsion; or, (2') Add a hydrophilic chain extender to carry out the chain extension reaction, and after cooling, add an organic amine alkaline neutralizer to balance the pH; add a low molecular weight alcohol chain extender to carry out the low temperature chain extension reaction; finally add deionized water and defoamer to carry out emulsification and dispersion, and filter to prepare a polyether-type high solids content solvent-free waterborne polyurethane emulsion.

8. The preparation method according to claim 7, wherein, In step (1), after heating to 100-120 ℃, vacuum is applied to remove the moisture inside the polyether polyol; And / or, in step (1), nitrogen gas is introduced after cooling to 40-60 °C; And / or, in step (1), the temperature of the prepolymerization reaction is 80-90 °C, and the time of the prepolymerization reaction is 1 hour; And / or, in steps (2) and (2'), the temperature of the chain extension reaction is 80-90 °C and the time of the chain extension reaction is 1 hour; And / or, in steps (2) and (2'), after cooling to 40-60 °C, an organic amine alkaline neutralizing agent is added to balance the pH; And / or, in steps (2) and (2'), the temperature of the low-temperature chain extension reaction is 40-50 °C, and the time of the low-temperature chain extension reaction is 3 hours.

9. A waterborne polyurethane elastomer, wherein the waterborne polyurethane elastomer is prepared by subjecting the waterborne polyurethane emulsion according to any one of claims 1-5 to low-temperature drying and high-temperature heat treatment. Preferably, the low-temperature drying is performed at 40-60°C until the shape is set, and the high-temperature heat treatment is performed at 100-110°C for 4-6 hours.

10. The method for preparing the waterborne polyurethane elastomer according to claim 9, the method comprising the following steps: The waterborne polyurethane emulsion according to any one of claims 1-5 is subjected to low-temperature drying and high-temperature heat treatment to prepare the waterborne polyurethane elastomer. Preferably, the low-temperature drying is performed at 40-60°C until the shape is set, and the high-temperature heat treatment is performed at 100-110°C for 4-6 hours.

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