A water-resistant non-isocyanate-based polyurethane adhesive, its preparation method and application

Abstract

This invention provides a water-resistant, non-isocyanate-based polyurethane adhesive, its preparation method, and its applications. The adhesive features a cross-linked network structure obtained by reacting a trifunctional five-membered cyclic carbonate with tris(2-aminoethyl)amine; the trifunctional five-membered cyclic carbonate has the structure shown in Formula I. This non-isocyanate-based polyurethane adhesive is suitable for a wider range of environmental conditions and applications. It can be used not only in dry environments but also maintains good adhesion performance in humid, high-humidity, and even underwater environments, unaffected by moisture. Even after being submerged underwater for a period of time, its adhesive strength after removal and air drying is still similar to that of the unsubmerged sample, thus meeting the bonding requirements in humid environments, such as bonding items in bathrooms, kitchens, and outdoor construction. This expands the application field of polyurethane adhesives, providing a more reliable solution for various industrial and civilian bonding needs.

Description

Technical Field

[0001] This invention belongs to the field of polymer adhesive technology, and particularly relates to a water-resistant non-isocyanate-based polyurethane adhesive, its preparation method and application. Background Technology

[0002] Adhesives have a wide range of applications in modern industry and daily life, from bonding building materials and furniture manufacturing to assembling electronic products. However, humid environments pose a significant challenge to the adhesive performance of adhesives. Moisture can penetrate the adhesive layer, weakening the bonding force between the adhesive and the adherend, leading to reduced bond strength. In unavoidable humid or wet environments, such as bathrooms, kitchens, toilets, basements, and outdoor construction, ordinary adhesives often fail to achieve ideal bonding results, potentially leading to problems such as non-adhesion, detachment, and bubbling. Furthermore, the curing reaction of traditional moisture-curing polyurethane adhesives is sensitive to humidity; excessively high humidity may cause over-reaction, forming bubbles or defects, further affecting bond strength and severely impacting the performance and lifespan of the finished product.

[0003] Therefore, developing an adhesive that can maintain good bonding performance in humid environments is of great practical significance. Summary of the Invention

[0004] The purpose of this invention is to provide a water-resistant non-isocyanate-based polyurethane adhesive, its preparation method and application. The adhesive has good water resistance, can maintain stable bonding performance in humid environments, and can even react directly in water to form an adhesive. At the same time, it avoids the use of toxic isocyanates, realizing the application of green, environmentally friendly, safe and non-toxic adhesives.

[0005] This invention provides a water-resistant non-isocyanate-based polyurethane adhesive having a cross-linked network structure, wherein the cross-linked network structure is obtained by reacting a trifunctional five-membered cyclic carbonate with tris(2-aminoethyl)amine;

[0006] The trifunctional five-membered cyclic carbonate has the structure shown in Formula I:

[0007] Formula I.

[0008] This invention provides a method for preparing a water-resistant, non-isocyanate-based polyurethane adhesive, comprising the following steps:

[0009] A) Glyceryl glycerol triglycidyl ether and an organic ammonium halide are mixed in a solvent and carbon dioxide gas is introduced to carry out the reaction, yielding a trifunctional five-membered cyclic carbonate.

[0010] B) A trifunctional five-membered cyclic carbonate is mixed with tris(2-aminoethyl)amine and reacted to obtain a water-resistant non-isocyanate-based polyurethane adhesive.

[0011] Preferably, the mass ratio of glycerol triglycidyl ether to organic ammonium halide is 100:(5~10).

[0012] The organohalogenated ammonium salt includes one or more of tetrabutylammonium chloride, tetrabutylammonium bromide, and benzyltriethylammonium chloride.

[0013] Preferably, in step A), the solvent is N,N-dimethylformamide, N,N-dimethylacetamide, or N-methylpyrrolidone; the mass ratio of glycerol triglycidyl ether to the solvent is 100:(25~50).

[0014] Preferably, the reaction temperature in step A) is 100~130℃ and the reaction time is 48~84 hours.

[0015] Preferably, in step A), the flow rate of carbon dioxide gas is 1.8~2.7 L / h.

[0016] Preferably, after completing the reaction in step A), the resulting reaction mixture is extracted with a mixture of ethyl acetate and water, and the organic layer is distilled to remove the catalyst and solvent, yielding a five-membered cyclic carbonate.

[0017] Preferably, the distillation of the organic layer includes the following steps:

[0018] The first stage of distillation is carried out at 45~55℃ until no obvious bubbles emerge. The second stage of distillation is carried out at 75~85℃ until no obvious bubbles emerge. The third stage of distillation is carried out at 125~135℃ until no solvent evaporates.

[0019] Preferably, in step B), the molar ratio of the trifunctional five-membered cyclic carbonate to tris(2-aminoethyl)amine is (95~105):100.

[0020] This invention provides the application of the water-resistant non-isocyanate-based polyurethane adhesive as described above in humid or wet environments.

[0021] This invention provides a water-resistant, non-isocyanate-based polyurethane adhesive with a cross-linked network structure obtained by reacting a trifunctional five-membered cyclic carbonate with tris(2-aminoethyl)amine; the trifunctional five-membered cyclic carbonate has the structure shown in Formula I. The non-isocyanate-based polyurethane adhesive of this invention is suitable for a wider range of environmental conditions and applications. It can be used not only in dry environments but also maintains good adhesion performance in humid, high-humidity, and even underwater environments, unaffected by moisture. Even after being submerged underwater for a period of time, its adhesive strength after removal and air drying is still similar to that of the unsubmerged sample, thus meeting the bonding requirements in humid environments, such as bonding items in bathrooms, kitchens, and outdoor construction. This expands the application field of polyurethane adhesives, providing a more reliable solution for various industrial and civilian bonding needs. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0023] Figure 1 The water contact angle of the adhesive in Example 1;

[0024] Figure 2 The water contact angle is that of the adhesive in Comparative Example 1. Detailed Implementation

[0025] This invention provides a water-resistant non-isocyanate-based polyurethane adhesive having a cross-linked network structure, wherein the cross-linked network structure is obtained by reacting a trifunctional five-membered cyclic carbonate with tris(2-aminoethyl)amine;

[0026] The trifunctional five-membered cyclic carbonate has the structure shown in Formula I:

[0027] Formula I.

[0028] In some embodiments of the present invention, one of the five-membered cyclic carbonates of the trifunctional five-membered cyclic carbonate reacts with one of the primary amines of the tri(2-aminoethyl)amine to open the ring, forming a carbamate bond. Each trifunctional five-membered cyclic carbonate is linked to three primary amine groups, and each tri(2-aminoethyl)amine is also linked to three carbamate bonds, thereby forming a cross-linked network structure, as shown in Formula II.

[0029] Formula II.

[0030] In this invention, the water-resistant non-isocyanate-based polyurethane adhesive contains block structures represented by Formula III and Formula IV, and the molar ratio of the block structure represented by Formula III to the block structure represented by Formula IV is preferably 1:(0.9~1.1), more preferably 1:1.

[0031] Formula III; Formula IV;

[0032] In this invention, Indicates a connection key.

[0033] This invention also provides a method for preparing a water-resistant non-isocyanate-based polyurethane adhesive, comprising the following steps:

[0034] A) Glyceryl glycerol triglycidyl ether and an organic ammonium halide are mixed in a solvent and carbon dioxide gas is introduced to carry out the reaction, yielding a trifunctional five-membered cyclic carbonate.

[0035] B) A trifunctional five-membered cyclic carbonate is mixed with tris(2-aminoethyl)amine and reacted to obtain a water-resistant non-isocyanate-based polyurethane adhesive.

[0036] In this invention, glycerol triglycidyl ether and an organic ammonium halide are mixed in a solvent, and carbon dioxide gas is introduced below the surface of the mixed solution to allow it to bubble continuously and react, thereby generating a mixed solution of a trifunctional five-membered cyclic carbonate and an organic ammonium halide.

[0037] In this invention, the organic ammonium halide salt is preferably one or more of tetrabutylammonium chloride (TBAI), tetrabutylammonium bromide (TBAB), and benzyltriethylammonium chloride (TEBA); the solvent is preferably N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), or N-methylpyrrolidone.

[0038] In this invention, the mass ratio of glycerol triglycidyl ether to organoammonium halide is preferably 100:(5~10), more preferably 100:(6~9), such as 100:5, 100:6, 100:7, 100:8, 100:9, 100:10, and preferably within the range of any of the above values ​​as the upper or lower limit; the mass ratio of glycerol triglycidyl ether to solvent is preferably 100:(25~50), more preferably 100:(30~45), such as 100:25, 100:30, 100:35, 100:40, 100:45, 100:50, and preferably within the range of any of the above values ​​as the upper or lower limit. The flow rate of carbon dioxide gas is preferably 1.8~2.7 L / h, more preferably 2.0~2.5 L / h, such as 1.8 L / h, 1.9 L / h, 2.0 L / h, 2.1 L / h, 2.2 L / h, 2.3 L / h, 2.4 L / h, 2.5 L / h, 2.6 L / h, 2.7 L / h, and preferably a range of values ​​with any of the above values ​​as the upper or lower limit.

[0039] In this invention, the reaction temperature is preferably 100~130℃, more preferably 110~120℃, such as 100℃, 105℃, 110℃, 115℃, 120℃, 125℃, 130℃, preferably a range of values ​​with any of the above values ​​as the upper or lower limit; the reaction time is preferably 48~84 hours, more preferably 48~72 hours.

[0040] After completing the above reaction, the present invention adds the obtained mixed solution of trifunctional five-membered cyclic carbonate and organoammonium halide to a mixed solution of ethyl acetate and water for extraction. After shaking the mixture, it is allowed to stand and separate into layers, and the lower pale yellow organic layer is removed. The above extraction operation is repeated 2 to 5 times to ensure that the catalyst organoammonium halide is completely removed. Then, the obtained pale yellow organic layer is subjected to vacuum distillation to remove the solvent, yielding a pure trifunctional five-membered cyclic carbonate product.

[0041] In this invention, the volume ratio of ethyl acetate to water in the mixed solution of ethyl acetate and water is preferably 1:(1~5), more preferably 1:(2~4).

[0042] In this invention, the vacuum distillation preferably includes three stages of distillation. The temperature of the first stage of distillation is preferably 45~55℃, more preferably 50℃, and the first stage of distillation continues until no obvious bubbles emerge. The temperature of the second stage of distillation is preferably 75~85℃, more preferably 80℃, and the second stage of distillation continues until no obvious bubbles emerge. The temperature of the third stage of distillation is 125~135℃, more preferably 130℃, and the third stage of distillation continues until no solvent evaporates.

[0043] After obtaining the trifunctional five-membered cyclic carbonate product, the present invention mixes the trifunctional five-membered cyclic carbonate with tris(2-aminoethyl)amine (TAEA), stirs it evenly at room temperature, and reacts it to obtain a water-resistant non-isocyanate-based polyurethane adhesive.

[0044] In this invention, one of the five-membered cyclic carbonates of the trifunctional five-membered cyclic carbonate reacts with one of the primary amines of tri(2-aminoethyl)amine to open the ring, forming a carbamate bond. The molar ratio of the trifunctional five-membered cyclic carbonate to tri(2-aminoethyl)amine is preferably (95~105):100, more preferably (98~102):100, such as 95:100, 96:100, 97:100, 98:100, 99:100, 100:100, 101:100, 102:100, 103:100, 104:100, 105:100, and preferably a range of values ​​with any of the above values ​​as the upper or lower limit.

[0045] In this invention, the reaction temperature is preferably room temperature, such as 20~30℃; the reaction time is preferably 10~40min, more preferably 20~30min.

[0046] The adhesive in this invention can cure underwater and has high bonding strength for the following reasons:

[0047] ① This invention uses tris(2-aminoethyl)amine (TAEA) as another component of the adhesive. TAEA is a trifunctional primary amine, which has two advantages: firstly, its small molecular weight allows for faster diffusion during the reaction; secondly, it has many reactive sites, resulting in stronger reactivity compared to other high molecular weight amines. Therefore, the adhesive in this invention can cure rapidly at room temperature without the need for other methods.

[0048] ② In addition, the reaction between the five-membered cyclic carbonate and the primary amine produces a urethane bond with a hydroxyl group at the β position after ring opening. Obviously, the material contains small polar groups such as hydroxyl, amino, and urethane groups. Furthermore, the adhesive structure of the present invention has a variety of polar groups and the polar groups are relatively dense, and the urethane groups are relatively close together, thus making the adhesive of the present invention hydrophobic.

[0049] ③ Due to the presence of a large number of strongly polar groups between adhesive molecules in this invention, the intermolecular forces are strong, which manifests as a particularly high viscosity of the adhesive. Therefore, it becomes difficult for water molecules to diffuse into the interior of the adhesive, and the influence they are affected by in water is also reduced.

[0050] In summary, the adhesive's fast curing speed, hydrophobicity, and high viscosity make it suitable for underwater curing and waterproofing applications.

[0051] Based on this, the present invention also provides an application of the water-resistant non-isocyanate-based polyurethane adhesive described above in a humid or wet environment. The present invention applies the water-resistant non-isocyanate-based polyurethane adhesive described above to the parts to be bonded, applies a certain pressure, and it can cure regardless of whether the environment is dry, humid, or submerged in water. Furthermore, experimental results show that the water-resistant non-isocyanate-based polyurethane adhesive of the present invention can cure rapidly underwater, and the bonding strength after underwater curing is even higher than that of samples cured at room temperature in a dry environment.

[0052] This invention provides a water-resistant, non-isocyanate-based polyurethane adhesive with the structure shown in Formula I. The non-isocyanate-based polyurethane adhesive of this invention is suitable for a wider range of environmental conditions and applications. It can be used not only in dry environments but also maintains good bonding performance in humid, high-humidity, and even underwater environments, unaffected by moisture. Even after being submerged underwater for a period of time, its bonding strength after removal and air drying is still similar to that of the unsubmerged sample, thus meeting the bonding requirements in humid environments, such as bonding items in bathrooms, kitchens, and outdoor construction. This expands the application areas of polyurethane adhesives, providing a more reliable solution for various industrial and civilian bonding needs.

[0053] To further illustrate the present invention, the following detailed description, in conjunction with embodiments, describes a water-resistant non-isocyanate-based polyurethane adhesive, its preparation method, and its application, but this should not be construed as limiting the scope of protection of the present invention.

[0054] Example 1

[0055] First, weigh 10.75g of glycerol triglycidyl ether (epoxide value 0.67), 1.5g of tetrabutylammonium iodide, and 5g of DMF and add them to a 50ml flask with a side arm. Then, introduce carbon dioxide below the surface of the reactants to make it bubble continuously.

[0056] Carbon dioxide was continuously introduced, the reaction temperature was 120°C, and the reaction lasted for 48 hours. After that, the apparatus was removed, and a pale yellow mixture was obtained.

[0057] Pour the mixture into a mixture of ethyl acetate and water, shake and let stand to separate the layers, remove the yellow organic layer, and repeat the above operation twice.

[0058] The obtained crude five-membered cyclic carbonate product was distilled under reduced pressure to remove the organic solvent, yielding the desired five-membered cyclic carbonate raw material.

[0059] Mix the five-membered cyclic carbonate with 3.51g TAEA until homogeneous. The resulting homogeneous viscous mixture can be used as a water-resistant adhesive.

[0060] Example 2

[0061] First, weigh 8g of glycerol triglycidyl ether (epoxide value 0.67), 0.5g of tetrabutylammonium bromide, and 3g of DMF and add them to a 50ml flask with a side arm. Then, introduce carbon dioxide below the surface of the reactants to make it bubble continuously.

[0062] Carbon dioxide was continuously introduced, the reaction temperature was 100℃, and the reaction lasted for 48 h. After that, the apparatus was removed, and a pale yellow mixture was obtained.

[0063] Pour the mixture into a mixture of ethyl acetate and water, shake and let stand to separate the layers, remove the yellow organic layer, and repeat the above operation twice.

[0064] The obtained crude five-membered cyclic carbonate product was distilled under reduced pressure to remove the organic solvent, yielding the desired five-membered cyclic carbonate raw material.

[0065] Mix the five-membered cyclic carbonate with 2.61g of TAEA until homogeneous. The resulting homogeneous viscous mixture can be used as a water-resistant adhesive.

[0066] Example 3

[0067] First, weigh 10g of glycerol triglycidyl ether (epoxide value 0.67), 0.5g of tetrabutylammonium iodide and 0.5g of tetrabutylammonium bromide, and add 10g of DMF to a 50ml flask with a side arm. Then, introduce carbon dioxide below the surface of the reactants to make it bubble continuously.

[0068] Carbon dioxide was continuously introduced, the reaction temperature was 100℃, and the reaction lasted for 72 h. After that, the apparatus was removed, and a pale yellow mixture was obtained.

[0069] Pour the mixture into a mixture of ethyl acetate and water, shake and let stand to separate the layers, remove the yellow organic layer, and repeat the above operation twice.

[0070] The obtained crude five-membered cyclic carbonate product was distilled under reduced pressure to remove the organic solvent, yielding the desired five-membered cyclic carbonate raw material.

[0071] Mix the five-membered cyclic carbonate with 2.61g of TAEA until homogeneous. The resulting homogeneous viscous mixture can be used as a water-resistant adhesive.

[0072] Example 4

[0073] First, weigh 20 g of glycerol triglycidyl ether (epoxide value 0.67), 2.0 g of tetrabutylammonium bromide, and 5 g of DMAc and add them to a 50 ml flask with a side arm. Then, introduce carbon dioxide below the surface of the reactants to make it bubble continuously.

[0074] Carbon dioxide was continuously introduced, the reaction temperature was 130℃, and the reaction lasted for 60 h. After that, the apparatus was removed, and a pale yellow mixture was obtained.

[0075] Pour the mixture into a mixture of ethyl acetate and water, shake and let stand to separate the layers, remove the yellow organic layer, and repeat the above operation twice.

[0076] The obtained crude five-membered cyclic carbonate product was distilled under reduced pressure to remove the organic solvent, yielding the desired five-membered cyclic carbonate raw material.

[0077] Mix the five-membered cyclic carbonate with 6.53g of TAEA until homogeneous. The resulting homogeneous viscous mixture can be used as a water-resistant adhesive.

[0078] Example 5

[0079] First, weigh 10g of glycerol triglycidyl ether (epoxide value 0.67), 0.5g of tetrabutylammonium iodide, 0.5g of benzyltriethylammonium chloride, and 5g of DMF and add them to a 50ml flask with a side arm. Then, introduce carbon dioxide below the surface of the reactants to make it bubble continuously.

[0080] Carbon dioxide was continuously introduced, the reaction temperature was 120°C, and the reaction lasted for 48 hours. After that, the apparatus was removed, and a pale yellow mixture was obtained.

[0081] Pour the mixture into a mixture of ethyl acetate and water, shake and let stand to separate the layers, remove the yellow organic layer, and repeat the above operation twice.

[0082] The obtained crude five-membered cyclic carbonate product was distilled under reduced pressure to remove the organic solvent, yielding the desired five-membered cyclic carbonate raw material.

[0083] Mix the five-membered cyclic carbonate with 3.43g of TAEA until homogeneous. The resulting homogeneous viscous mixture can be used as a water-resistant adhesive.

[0084] Comparative Example 1

[0085] The adhesive NIPU-D400 was prepared according to the method in Example 1. The difference was that in Comparative Example 1, 14.4 g of polyetheramine D400 (the molar ratio of the primary amine group in polyetheramine D400 to the epoxy group in glycerol triglycidyl ether was 1:1) was used instead of 3.51 g of TAEA in Example 1.

[0086] Contact angle test

[0087] The water contact angles of the adhesives in Example 1 and Comparative Example 1 are as follows: Figures 1-2 As shown, Figure 1 The water contact angle of the adhesive in Example 1 is... Figure 2The water contact angle of the adhesive in Comparative Example 1 is given by... Figures 1-2 The comparison shows that the water contact angle of adhesive NIPU-D400 in Comparative Example 1 (104.2°) is smaller than that of NIPU-TAEA in Example 1 (116.7°), indicating that the NIPU-TAEA adhesive in this invention has stronger hydrophobic properties.

[0088] Water resistance test:

[0089] Two substrates, aluminum sheet (Al) and stainless steel (SS), were selected for the bonding test. The following bonding of stainless steel sheet and aluminum sheet, bonding area, and test method follow the national standard GB / T7124-2008, and the tensile rate is 8 mm / min.

[0090] Experimental group: The adhesive (NIPU) prepared in Example 1 and Comparative Example 1 was applied to two standard aluminum sheets (Al) or stainless steel sheets (SS). The two aluminum sheets (stainless steel sheets) were tightly adhered together and fixed with clips. The bonded parts were then immediately placed in water, removed after 1 hour, and placed indoors for two days before testing.

[0091] Control group: The adhesive prepared in Example 1 and Comparative Example 1 was applied to two standard aluminum or stainless steel sheets, the two aluminum (stainless steel) sheets were tightly attached together, fixed with clips, and tested after being placed indoors for two days.

[0092] The experimental results are shown in Table 1:

[0093] Table 1 Water resistance test results

[0094]

[0095] The bonding strength was tested using the tensile test described above. The results showed that, under natural indoor conditions, the bonding strength of the adhesive to aluminum sheets and stainless steel was 6.34±0.91 MPa and 6.99±1.1 MPa, respectively. After soaking in water for 1 hour and then air-drying, the bonding strength to aluminum sheets was 7.28±1.23 MPa, which was higher than the bonding strength under dry conditions, representing an increase of 15.83%. The bonding strength to stainless steel sheets remained at 7.51±1.29 MPa, an increase of 7.44% compared to the dry conditions. In contrast, the adhesive in Comparative Example 1 reacted extremely slowly at room temperature and required heating to cure. At 50°C, the curing time was over 72 hours, and the cured bonding strength was only 1 / 10 of that of the adhesive in Example 1. Furthermore, the bonding strength of the adhesive in Example 1 after curing at 50°C was far lower than that cured at room temperature and underwater. This indicates that the adhesive of this invention has excellent water resistance and can maintain stable bonding performance in humid environments, even surpassing the strength under dry indoor conditions.

[0096] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A water-resistant non-isocyanate-based polyurethane adhesive having a cross-linked network structure, said cross-linked network structure being obtained by reacting a trifunctional five-membered cyclic carbonate with tris(2-aminoethyl)amine; The trifunctional five-membered cyclic carbonate has the structure shown in Formula I: Equation I.

2. A method for preparing a water-resistant non-isocyanate-based polyurethane adhesive, comprising the following steps: A) Glyceryl glycerol triglycidyl ether and an organic ammonium halide are mixed in a solvent and carbon dioxide gas is introduced to carry out the reaction, yielding a trifunctional five-membered cyclic carbonate. B) A trifunctional five-membered cyclic carbonate is mixed with tris(2-aminoethyl)amine and reacted to obtain a water-resistant non-isocyanate-based polyurethane adhesive.

3. The method for preparing the water-resistant non-isocyanate-based polyurethane adhesive according to claim 2, characterized in that, The mass ratio of the glycerol triglycidyl ether to the organic ammonium halide salt is 100:(5~10). The organohalogenated ammonium salt includes one or more of tetrabutylammonium chloride, tetrabutylammonium bromide, and benzyltriethylammonium chloride.

4. The method for preparing the water-resistant non-isocyanate-based polyurethane adhesive according to claim 2, characterized in that, In step A), the solvent is N,N-dimethylformamide, N,N-dimethylacetamide, or N-methylpyrrolidone; the mass ratio of glycerol triglycidyl ether to the solvent is 100:(25~50).

5. The method for preparing the water-resistant non-isocyanate-based polyurethane adhesive according to claim 2, characterized in that, The reaction temperature in step A) is 100~130℃, and the reaction time is 48~84 hours.

6. The method for preparing the water-resistant non-isocyanate-based polyurethane adhesive according to claim 2, characterized in that, In step A), the flow rate of carbon dioxide gas is 1.8~2.7 L / h.

7. The method for preparing the water-resistant non-isocyanate-based polyurethane adhesive according to claim 2, characterized in that, After completing the reaction in step A), the resulting reaction mixture was extracted with a mixture of ethyl acetate and water, and the organic layer was distilled to remove the catalyst and solvent, yielding a five-membered cyclic carbonate.

8. The method for preparing the water-resistant non-isocyanate-based polyurethane adhesive according to claim 7, characterized in that, Distillation of the organic layer includes the following steps: The first stage of distillation is carried out at 45~55℃ until no obvious bubbles emerge. The second stage of distillation is carried out at 75~85℃ until no obvious bubbles emerge. The third stage of distillation is carried out at 125~135℃ until no solvent evaporates.

9. The method for preparing the water-resistant non-isocyanate-based polyurethane adhesive according to claim 2, characterized in that, In step B), the molar ratio of the trifunctional five-membered cyclic carbonate to tris(2-aminoethyl)amine is (95~105):

100.

10. The application of the water-resistant non-isocyanate polyurethane adhesive as described in claim 1 or the water-resistant non-isocyanate polyurethane adhesive prepared by the preparation method according to any one of claims 2 to 8 in a humid or wet environment.

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