Non-toxic anionic waterborne polyurethane and preparation method thereof

Abstract

The invention relates to the technical field of polyurethane materials, and discloses nontoxic anionic waterborne polyurethane and a preparation method thereof.The preparation method includes the steps that a polyurethane prepolymer is stirred and heated, a grafting product 1 and potassium persulfate are dropwise added, a grafting product 2 and nano-silicon dioxide are added, banburying is conducted in an internal mixer, and the nontoxic anionic waterborne polyurethane is obtained. The grafting product 1 is prepared by grafting diphenyldihydroxysilane with acrylamide, and the grafting product 2 is prepared by grafting acrylonitrile with vinyl trimethoxy silane after amino-terminated hyperbranched. The compatibility between materials can be effectively improved, and the characteristics of mechanical properties, wear resistance, aging resistance and the like are improved. The non-toxic anionic waterborne polyurethane prepared by the invention has good mechanical properties, can still retain good tensile strength, impact strength and elongation at break after aging, has good aging resistance, and also has excellent wear resistance.

Description

Technical Field

[0001] The invention relates to the technical field of polyurethane materials, in particular to a non-toxic anionic waterborne polyurethane and a preparation method thereof. Background Art

[0002] With the improvement of environmental awareness and the increasingly stringent requirements for material safety, traditional solvent-based polyurethanes are gradually restricted due to the use of a large amount of organic solvents, environmental pollution and toxicity problems. Although some existing water-based polyurethanes have solved environmental problems to a certain extent, they still have deficiencies in performance and safety. For example, some products may contain potential toxic and harmful substances, or have poor performance in mechanical properties, aging resistance, wear resistance, etc., and cannot meet the needs of the shoe production field. Therefore, it is of great significance to develop an anionic water-based polyurethane that has both excellent performance and is non-toxic and environmentally friendly. Summary of the invention

[0003] 1. Technical issues to be resolved

[0004] In view of the deficiencies in the prior art, the present invention provides a non-toxic anionic waterborne polyurethane and a preparation method thereof.

[0005] (II) Technical solution

[0006] A method for preparing non-toxic anionic waterborne polyurethane comprises the following steps:

[0007] S1, polypropylene oxide diol are dehydrated in a vacuum drying oven for 3-6 hours and then placed in a flask, diphenyl toluene diisocyanate is added under the protection of dry, high-purity nitrogen, a catalyst dibutyltin dilaurate is added dropwise, the temperature is raised to 60-80°C, the reaction is carried out for 2-6 hours, a chain extender dimethylol propionic acid is added, the temperature is lowered to 30-40°C, triethylamine is added, and a polyurethane prepolymer is obtained;

[0008] S2, adding diphenyldihydroxysilane to a 20% by mass acetone solution, stirring and dissolving to prepare a diphenyldihydroxysilane solution, dissolving acrylamide in water to prepare an acrylamide solution, heating the diphenyldihydroxysilane solution to 45-60° C., adding the acrylamide solution, stirring evenly, adding initiator ammonium persulfate, heating to 80-90° C. to react for 3-6 hours, and removing the solvent by distillation under reduced pressure to obtain a grafted product 1;

[0009] S3, placing diethylenetriamine in an ice water bath, passing nitrogen, adding vinyltrimethoxysilane to the ethanol solution and stirring evenly to obtain a vinyltrimethoxysilane solution, slowly dropping the vinyltrimethoxysilane solution and methanol, reacting at 20-30°C for 3-6h, removing the solvent under reduced pressure to obtain amino-terminated trimethoxysilane;

[0010] S4, mixing amino-terminated trimethoxysilane and acrylonitrile, stirring evenly, adding catalysts of ammonium persulfate and sodium bisulfite, reacting at 60-80° C. for 1-3 hours, to obtain a grafted product 2;

[0011] S5. Stir the polyurethane prepolymer and heat it to 80-90° C., drop the grafted product 1 and potassium persulfate, and react for 2-6 hours. Then add the grafted product 2 and nano-silicon dioxide, add the mixture to an internal mixer and mix them to obtain a non-toxic anionic waterborne polyurethane.

[0012] Preferably, in step S1, the mass ratio of polypropylene oxide glycol, diphenyl toluene diisocyanate, dibutyltin dilaurate, dimethylol propionic acid, and triethylamine is 1:0.6-0.8:0.02-0.05:0.08-0.15:0.05-0.12.

[0013] Preferably, in step S2, the mass ratio of diphenyldihydroxysilane, acrylamide and ammonium persulfate is 1:1-1.5:0.05-0.12.

[0014] Preferably, in step S3, the mass ratio of diethylenetriamine, vinyltrimethoxysilane and methanol is 1:0.4-0.6:1.5-2.

[0015] Preferably, in step S4, the mass ratio of terminal aminotrimethoxysilane, acrylonitrile, ammonium persulfate and sodium bisulfite is 1:0.3-0.6:0.02-0.05:0.02-0.05.

[0016] Preferably, in step S5, the mass ratio of the polyurethane prepolymer, the grafted product 1, potassium persulfate, the grafted product 2, and the nano-silicon dioxide is 1:0.2-0.4:0.02-0.05:0.1-0.3:0.05-0.1.

[0017] Preferably, the invention is used in shoe production materials.

[0018] (III) Beneficial technical effects

[0019] Grafted product 1 is made of acrylamide grafted with diphenyldihydroxysilane, and grafted product 2 is made of vinyltrimethoxysilane grafted with acrylonitrile after terminal amino hyperbranching. It can effectively improve the compatibility between materials and enhance mechanical properties, wear resistance, aging resistance and other properties.

[0020] The non-toxic anionic waterborne polyurethane prepared by the invention has good mechanical properties, and after aging, can still retain good tensile strength, impact strength and elongation at break, has good aging resistance, and also has excellent wear resistance.

[0021] The production process of the invention is green and environmentally friendly, the production process is safe and efficient, the product is non-toxic, and the material can be applied to the production of shoes with more stable performance. DETAILED DESCRIPTION

[0022] Example 1

[0023] S1, 10kg of polypropylene oxide diol was dehydrated in a vacuum drying oven for 3h and then placed in a flask. 6kg of diphenyltoluene diisocyanate was added under the protection of dry, high-purity nitrogen. 0.2kg of catalyst dibutyltin dilaurate was added dropwise. The temperature was raised to 60°C and reacted for 2h. 0.8kg of chain extender dihydroxymethylpropionic acid was added. The temperature was lowered to 30°C and 0.5kg of triethylamine was added to obtain a polyurethane prepolymer.

[0024] S2. Add 10 kg of diphenyldihydroxysilane into 60 L of 20% acetone solution, stir and dissolve to prepare a diphenyldihydroxysilane solution, dissolve 10 kg of acrylamide in 80 L of water to prepare an acrylamide solution, heat the diphenyldihydroxysilane solution to 45°C, add the acrylamide solution, stir evenly, add 0.5 kg of initiator ammonium persulfate, heat to 80°C, react for 3 hours, and remove the solvent by distillation under reduced pressure to obtain a grafted product 1.

[0025] S3. Place 10 kg of diethylenetriamine in an ice-water bath and pass nitrogen. Add 4 kg of vinyltrimethoxysilane into 60 L of ethanol solution and stir evenly to obtain a vinyltrimethoxysilane solution. Slowly drop the vinyltrimethoxysilane solution and 15 kg of methanol. React at 20°C for 3 hours. Remove the solvent under reduced pressure to obtain amino-terminated trimethoxysilane.

[0026] S4. Mix 10 kg of amino-terminated trimethoxysilane and 3 kg of acrylonitrile, stir evenly, add 0.2 kg of ammonium persulfate and 0.2 kg of sodium bisulfite as catalysts, and react at 60° C. for 1 hour to obtain a grafted product 2.

[0027] S5. Stir and heat 10 kg of polyurethane prepolymer to 80° C., drop 2 kg of graft product 1 and 0.2 kg of potassium persulfate, react for 2 h, then add 1 kg of graft product 2 and 0.5 kg of nano-silicon dioxide, add to an internal mixer and mix to obtain non-toxic anionic waterborne polyurethane.

[0028] Example 2

[0029] S1, 10kg of polypropylene oxide diol was dehydrated in a vacuum drying oven for 6h and then placed in a flask. 8kg of diphenyltoluene diisocyanate was added under the protection of dry, high-purity nitrogen. 0.5kg of catalyst dibutyltin dilaurate was added dropwise. The temperature was raised to 80°C and reacted for 6h. 1.5kg of chain extender dihydroxymethylpropionic acid was added. The temperature was lowered to 40°C and 1.2kg of triethylamine was added to obtain a polyurethane prepolymer.

[0030] S2. Add 10 kg of diphenyldihydroxysilane into 80 L of 20% acetone solution by mass, stir and dissolve to prepare a diphenyldihydroxysilane solution, dissolve 15 kg of acrylamide in 100 L of water to prepare an acrylamide solution, heat the diphenyldihydroxysilane solution to 60°C, add the acrylamide solution, stir evenly, add 1.2 kg of initiator ammonium persulfate, heat to 90°C to react for 6 hours, and remove the solvent by distillation under reduced pressure to obtain a grafted product 1.

[0031] S3. Place 10 kg of diethylenetriamine in an ice-water bath and pass nitrogen. Add 6 kg of vinyltrimethoxysilane into 100 L of ethanol solution and stir evenly to obtain a vinyltrimethoxysilane solution. Slowly drop the vinyltrimethoxysilane solution and 20 kg of methanol. React at 30°C for 6 hours. Remove the solvent under reduced pressure to obtain amino-terminated trimethoxysilane.

[0032] S4. Mix 10 kg of amino-terminated trimethoxysilane and 6 kg of acrylonitrile, stir evenly, add 0.5 kg of ammonium persulfate and 0.5 kg of sodium bisulfite as catalysts, and react at 80° C. for 3 h to obtain a grafted product 2.

[0033] S5. Stir and heat 10 kg of polyurethane prepolymer to 90° C., drop 4 kg of grafted product 1 and 0.5 kg of potassium persulfate, react for 6 hours, then add 3 kg of grafted product 2 and 1 kg of nano-silicon dioxide, add to an internal mixer and mix to obtain non-toxic anionic waterborne polyurethane.

[0034] Example 3

[0035] S1, 10kg of polypropylene oxide diol was dehydrated in a vacuum drying oven for 4h and then placed in a flask. 6.5kg of diphenyltoluene diisocyanate was added under the protection of dry, high-purity nitrogen. 0.3kg of catalyst dibutyltin dilaurate was added dropwise. The temperature was raised to 65°C and reacted for 3h. 0.9kg of chain extender dihydroxymethylpropionic acid was added. The temperature was lowered to 40°C and 0.6kg of triethylamine was added to obtain a polyurethane prepolymer.

[0036] S2. Add 10 kg of diphenyldihydroxysilane into 70 L of 20% acetone solution, stir and dissolve to prepare a diphenyldihydroxysilane solution, dissolve 12 kg of acrylamide in 90 L of water to prepare an acrylamide solution, heat the diphenyldihydroxysilane solution to 50°C, add the acrylamide solution, stir evenly, add 0.8 kg of initiator ammonium persulfate, heat to 80°C, react for 5 hours, and remove the solvent by distillation under reduced pressure to obtain a grafted product 1.

[0037] S3. Place 10 kg of diethylenetriamine in an ice-water bath and pass nitrogen. Add 4.2 kg of vinyltrimethoxysilane to 80 L of ethanol solution and stir evenly to obtain a vinyltrimethoxysilane solution. Slowly drop the vinyltrimethoxysilane solution and 18 kg of methanol. React at 25 °C for 4 hours. Remove the solvent under reduced pressure to obtain amino-terminated trimethoxysilane.

[0038] S4. Mix 10 kg of amino-terminated trimethoxysilane and 4 kg of acrylonitrile, stir evenly, add 0.3 kg of ammonium persulfate and 0.3 kg of sodium bisulfite as catalysts, and react at 70° C. for 1.5 h to obtain a grafted product 2.

[0039] S5. Stir and heat 10 kg of polyurethane prepolymer to 90° C., drop 2.5 kg of grafted product 1 and 0.4 kg of potassium persulfate, react for 3 hours, then add 1.5 kg of grafted product 2 and 0.8 kg of nano-silicon dioxide, add to an internal mixer and mix to obtain non-toxic anionic waterborne polyurethane.

[0040] Example 4

[0041] S1, 10kg of polypropylene oxide diol was dehydrated in a vacuum drying oven for 5h and then placed in a flask. 7.2kg of diphenyltoluene diisocyanate was added under the protection of dry, high-purity nitrogen. 0.4kg of catalyst dibutyltin dilaurate was added dropwise. The temperature was raised to 70°C and reacted for 4h. 1kg of chain extender dihydroxymethylpropionic acid was added. The temperature was lowered to 40°C and 1kg of triethylamine was added to obtain a polyurethane prepolymer.

[0042] S2. Add 10 kg of diphenyldihydroxysilane into 60 L of 20% acetone solution by mass, stir and dissolve to prepare a diphenyldihydroxysilane solution, dissolve 13 kg of acrylamide in 100 L of water to prepare an acrylamide solution, heat the diphenyldihydroxysilane solution to 55°C, add the acrylamide solution, stir evenly, add 0.8 kg of initiator ammonium persulfate, heat to 90°C to react for 4 hours, and remove the solvent by distillation under reduced pressure to obtain a grafted product 1.

[0043] S3. Place 10 kg of diethylenetriamine in an ice-water bath and pass nitrogen. Add 5.2 kg of vinyltrimethoxysilane into 90 L of ethanol solution and stir evenly to obtain a vinyltrimethoxysilane solution. Slowly drop the vinyltrimethoxysilane solution and 19 kg of methanol. React at 25 °C for 5 hours. Remove the solvent under reduced pressure to obtain amino-terminated trimethoxysilane.

[0044] S4. Mix 10 kg of amino-terminated trimethoxysilane and 5 kg of acrylonitrile, stir evenly, add 0.4 kg of ammonium persulfate and 0.4 kg of sodium bisulfite as catalysts, and react at 70° C. for 2.5 h to obtain a grafted product 2.

[0045] S5. Stir and heat 10 kg of polyurethane prepolymer to 90° C., drop 3.6 kg of grafted product 1 and 0.3 kg of potassium persulfate, react for 5 hours, then add 2.6 kg of grafted product 2 and 0.8 kg of nano-silicon dioxide, add to an internal mixer and mix to obtain non-toxic anionic waterborne polyurethane.

[0046] Example 5

[0047] S1, 10kg of polypropylene oxide diol was dehydrated in a vacuum drying oven for 4h and then placed in a flask. 6kg of diphenyltoluene diisocyanate was added under the protection of dry, high-purity nitrogen. 0.5kg of catalyst dibutyltin dilaurate was added dropwise. The temperature was raised to 80°C and reacted for 5h. 1.3kg of chain extender dihydroxymethylpropionic acid was added. The temperature was lowered to 30°C and 1kg of triethylamine was added to obtain a polyurethane prepolymer.

[0048] S2. Add 10 kg of diphenyldihydroxysilane into 70 L of 20% acetone solution, stir and dissolve to prepare a diphenyldihydroxysilane solution, dissolve 15 kg of acrylamide in 80 L of water to prepare an acrylamide solution, heat the diphenyldihydroxysilane solution to 45°C, add the acrylamide solution, stir evenly, add 0.9 kg of initiator ammonium persulfate, heat to 90°C, react for 5 hours, and remove the solvent by distillation under reduced pressure to obtain a grafted product 1.

[0049] S3. Place 10 kg of diethylenetriamine in an ice-water bath and pass nitrogen. Add 4.6 kg of vinyltrimethoxysilane to 100 L of ethanol solution and stir evenly to obtain a vinyltrimethoxysilane solution. Slowly drop the vinyltrimethoxysilane solution and 20 kg of methanol. React at 20°C for 3 hours. Remove the solvent under reduced pressure to obtain amino-terminated trimethoxysilane.

[0050] S4. Mix 10 kg of amino-terminated trimethoxysilane and 5.5 kg of acrylonitrile, stir evenly, add 0.2 kg of ammonium persulfate and 0.5 kg of sodium bisulfite as catalysts, and react at 80° C. for 2 h to obtain a grafted product 2.

[0051] S5. Stir and heat 10 kg of polyurethane prepolymer to 80° C., drop 4 kg of graft product 1 and 0.3 kg of potassium persulfate, react for 6 hours, then add 2 kg of graft product 2 and 0.9 kg of nano-silicon dioxide, add to an internal mixer and mix to obtain non-toxic anionic waterborne polyurethane.

[0052] Comparative Example 1

[0053] S1, 10kg of polypropylene oxide diol was dehydrated in a vacuum drying oven for 3h and then placed in a flask. 6kg of diphenyltoluene diisocyanate was added under the protection of dry, high-purity nitrogen. 0.2kg of catalyst dibutyltin dilaurate was added dropwise. The temperature was raised to 60°C and reacted for 2h. 0.8kg of chain extender dihydroxymethylpropionic acid was added. The temperature was lowered to 30°C and 0.5kg of triethylamine was added to obtain a polyurethane prepolymer.

[0054] S2. Place 10 kg of diethylenetriamine in an ice-water bath and pass nitrogen. Add 4 kg of vinyltrimethoxysilane to 60 L of ethanol solution and stir evenly to obtain a vinyltrimethoxysilane solution. Slowly drop the vinyltrimethoxysilane solution and 15 kg of methanol. React at 20°C for 3 hours. Remove the solvent under reduced pressure to obtain amino-terminated trimethoxysilane.

[0055] S3. Mix 10 kg of amino-terminated trimethoxysilane and 3 kg of acrylonitrile, stir evenly, add 0.2 kg of ammonium persulfate and 0.2 kg of sodium bisulfite as catalysts, and react at 60° C. for 1 hour to obtain a grafted product 2.

[0056] S4, stirring 10 kg of polyurethane prepolymer and heating it to 80° C., adding 1 kg of grafted product 2 and 0.5 kg of nano-silicon dioxide, adding them into an internal mixer and mixing them to obtain non-toxic anionic water-based polyurethane.

[0057] Comparative Example 2

[0058] S1, 10kg of polypropylene oxide diol was dehydrated in a vacuum drying oven for 3h and then placed in a flask. 6kg of diphenyltoluene diisocyanate was added under the protection of dry, high-purity nitrogen. 0.2kg of catalyst dibutyltin dilaurate was added dropwise. The temperature was raised to 60°C and reacted for 2h. 0.8kg of chain extender dihydroxymethylpropionic acid was added. The temperature was lowered to 30°C and 0.5kg of triethylamine was added to obtain a polyurethane prepolymer.

[0059] S2. Add 10 kg of diphenyldihydroxysilane into 60 L of 20% acetone solution, stir and dissolve to prepare a diphenyldihydroxysilane solution, dissolve 10 kg of acrylamide in 80 L of water to prepare an acrylamide solution, heat the diphenyldihydroxysilane solution to 45°C, add the acrylamide solution, stir evenly, add 0.5 kg of initiator ammonium persulfate, heat to 80°C, react for 3 hours, and remove the solvent by distillation under reduced pressure to obtain a grafted product 1.

[0060] S3, stirring 10 kg of polyurethane prepolymer and heating it to 80°C, adding 2 kg of grafted product 1 and 0.2 kg of potassium persulfate dropwise, reacting for 2 hours, then adding 0.5 kg of nano-silicon dioxide, adding it to an internal mixer and mixing it to obtain non-toxic anionic waterborne polyurethane.

[0061] Comparative Example 3

[0062] S1, 10kg of polypropylene oxide diol was dehydrated in a vacuum drying oven for 3h and then placed in a flask. 6kg of diphenyltoluene diisocyanate was added under the protection of dry, high-purity nitrogen. 0.2kg of catalyst dibutyltin dilaurate was added dropwise. The temperature was raised to 60°C and reacted for 2h. 0.8kg of chain extender dihydroxymethylpropionic acid was added. The temperature was lowered to 30°C and 0.5kg of triethylamine was added to obtain a polyurethane prepolymer.

[0063] S2. Stir 10 kg of polyurethane prepolymer and heat it to 80° C., add 0.5 kg of nano-silicon dioxide, and add it to an internal mixer for internal mixing to obtain non-toxic anionic water-based polyurethane.

[0064] Performance Test:

[0065] Aging resistance test: The polyurethane materials prepared in Examples 1 to 5 and Comparative Examples 1 to 3 were placed in a sole mold, and the soles were made by stamping the molds. An aging test was performed at 100° C. for 48 hours, and the tensile strength, impact strength and elongation at break of the sole materials were measured.

[0066] Wear resistance test: Referring to ASTM-D1630, the size of the polyurethane material of Examples 1 to 5 and Comparative Examples 1 to 3 is 25.4×25.4 mm. The number of friction wheel turns required for the test piece to reach a quantitative wear depth of 2.54 mm is observed under a quantitative load (three groups of 2265 g). The wear resistance of the test sole is evaluated by the relative volume loss of the sole sample. Pre-grinding is first performed to match the wear surface of the sandpaper; the outer diameter of the runner is 150 mm, the shaft speed is 45 rpm, and the sandpaper particle size is 40#;

[0067] Table 1

[0068] Group Tensile strength MPa <![CDATA[Impact strength kJ / m 2 > Elongation at break % Wear resistance % Example 1 10.8 35 18.3 65 Example 2 10.9 38 18.5 62 Example 3 10.5 36 17.9 63 Example 4 11.2 34 18.2 64 Example 5 10.8 34 18.6 67 Comparative Example 1 9.3 30 16.5 57 Comparative Example 2 9.1 28 16.4 55 Comparative Example 3 8.5 25 16.1 51

[0069] It can be seen from Table 1 that the aging resistance and wear resistance of Examples 1 to 5 are better than those of Comparative Examples 1 to 3. The polyurethane sole materials prepared in Examples 1 to 3 have good aging resistance and wear resistance.

[0070] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a non-toxic anionic waterborne polyurethane, characterized in that: The following steps are involved: S1, polypropylene oxide diol are dehydrated in a vacuum drying oven for 3-6 hours and then placed in a flask, diphenyl toluene diisocyanate is added under the protection of dry, high-purity nitrogen, a catalyst dibutyltin dilaurate is added dropwise, the temperature is raised to 60-80°C, the reaction is carried out for 2-6 hours, a chain extender dimethylol propionic acid is added, the temperature is lowered to 30-40°C, triethylamine is added, and a polyurethane prepolymer is obtained; S2, adding diphenyldihydroxysilane to a 20% by mass acetone solution, stirring and dissolving to prepare a diphenyldihydroxysilane solution, dissolving acrylamide in water to prepare an acrylamide solution, heating the diphenyldihydroxysilane solution to 45-60° C., adding the acrylamide solution, stirring evenly, adding initiator ammonium persulfate, heating to 80-90° C. to react for 3-6 hours, and removing the solvent by distillation under reduced pressure to obtain a grafted product 1; S3, placing diethylenetriamine in an ice water bath, passing nitrogen, adding vinyltrimethoxysilane to the ethanol solution and stirring evenly to obtain a vinyltrimethoxysilane solution, slowly dropping the vinyltrimethoxysilane solution and methanol, reacting at 20-30°C for 3-6h, removing the solvent under reduced pressure to obtain amino-terminated trimethoxysilane; S4, mixing amino-terminated trimethoxysilane and acrylonitrile, stirring evenly, adding catalysts of ammonium persulfate and sodium bisulfite, reacting at 60-80° C. for 1-3 hours, to obtain a grafted product 2; S5. Stir the polyurethane prepolymer and heat it to 80-90° C., drop the grafted product 1 and potassium persulfate, and react for 2-6 hours. Then add the grafted product 2 and nano-silicon dioxide, add the mixture to an internal mixer and mix them to obtain a non-toxic anionic waterborne polyurethane.

2. The method for preparing a non-toxic anionic waterborne polyurethane according to claim 1, characterized in that: In the step S1, the mass ratio of polypropylene oxide glycol, diphenyl toluene diisocyanate, dibutyltin dilaurate, dimethylol propionic acid and triethylamine is 1:0.6-0.8:0.02-0.05:0.08-0.15:0.05-0.

12.

3. The method for preparing a non-toxic anionic waterborne polyurethane according to claim 1, characterized in that: In the step S2, the mass ratio of diphenyldihydroxysilane, acrylamide and ammonium persulfate is 1:1-1.5:0.05-0.

12.

4. The method for preparing a non-toxic anionic waterborne polyurethane according to claim 1, characterized in that: In the step S3, the mass ratio of diethylenetriamine, vinyltrimethoxysilane and methanol is 1:0.4-0.6:1.5-2.

5. The method for preparing a non-toxic anionic waterborne polyurethane according to claim 1, characterized in that: In the step S4, the mass ratio of terminal aminotrimethoxysilane, acrylonitrile, ammonium persulfate and sodium bisulfite is 1:0.3-0.6:0.02-0.05:0.02-0.

05.

6. The method for preparing a non-toxic anionic waterborne polyurethane according to claim 1, characterized in that: In the step S5, the mass ratio of the polyurethane prepolymer, the grafted product 1, potassium persulfate, the grafted product 2, and the nano-silicon dioxide is 1: 0.2-0.4: 0.02-0.05: 0.1-0.3: 0.05-0.

1.

7. A method for preparing a non-toxic anionic waterborne polyurethane, wherein the non-toxic anionic waterborne polyurethane is prepared, characterized in that: Application in shoe production materials.