A non-isocyanate polyurethane adhesive resistant to extreme environments and a method of making the same

Abstract

This invention belongs to the field of preparation of non-isocyanate polyurethanes, specifically relating to a method for preparing a non-isocyanate polyurethane adhesive resistant to extreme environments. By preparing cyclic carbonate monomers with rigid structures, selecting the types of di / polyamines, and adjusting the ratio of flexible segment amine compounds to rigid amine compounds, a series of non-isocyanate polyurethane adhesives with excellent mechanical properties are prepared, achieving controllable bonding strength and resistance to extreme environments. The adhesive synthesis method of this invention is simple, and the reaction conditions are easy to control. The lap shear strength of the bonding Al reaches 16.7 MPa; the lap shear strength reaches 15.6 MPa at a low temperature of -196℃; and the lap shear strength reaches 15.2 MPa at a high temperature of 190℃. After immersion in a solvent for 24 hours, the lap shear strength of the bonded sample can still be maintained above 15.4 MPa, reaching 16.5 MPa. This method has wide applications in aerospace, medical devices, and chemical product packaging, and has good market prospects.

Description

Technical Field

[0001] This invention belongs to the field of preparation of non-isocyanate polyurethane, specifically relating to a non-isocyanate polyurethane adhesive resistant to extreme environments and its preparation method. Background Technology

[0002] Adhesives for aerospace applications are key materials in the manufacture of high-tech products such as launch vehicles, satellites, and spacecraft. These aerospace devices must withstand the severe challenges of extreme environments during launch, orbital operation, and recovery. The high acceleration and intense vibrations during launch, the ultra-low and ultra-high temperature cycles after entering space, the material stability under high vacuum conditions, and the unique environments exposed to space radiation and micrometeorite impacts make ordinary adhesives inadequate. Therefore, adhesives resistant to extreme environments have become a major and critical technical challenge that cannot be avoided and must be properly addressed in the research and development of high-tech equipment such as aerospace equipment, and it has significant scientific importance.

[0003] Non-isocyanate polyurethane (NIPU), as a novel polyurethane material, has attracted increasing attention in recent years. Compared with traditional polyurethane adhesives, NIPU has several unique advantages, one of which is that it does not use toxic and moisture-sensitive isocyanate monomers, a major problem faced by polyurethanes during synthesis, transportation, and storage. NIPU is prepared through the addition polymerization of cyclic carbonates and amine compounds, generating a large number of hydroxyl groups on the polymer backbone. These hydroxyl groups can form intermolecular and intramolecular hydrogen bonds. The abundant hydrogen bonds enable more interactions with the substrate surface, giving NIPU excellent tensile strength and lap shear strength. Patent application CN 117586499 A discloses a resveratrol-based non-isocyanate polyurethane adhesive, which prepares lap plates using stainless steel as a substrate, with the sample CREPP-1.0 (9.2 MPa) reaching the maximum strength. Patent application CN 117363297 A discloses a high-performance non-isocyanate polyurethane adhesive material that can achieve bonding, repair, and protection of various substrates in ultra-low temperature environments. The bonding strength to steel plates exceeds 14 MPa and the bonding strength to aluminum alloys exceeds 11 MPa in ultra-low temperature (liquid nitrogen, -196℃) environments.

[0004] In summary, although NIPU has been extensively studied in the adhesive field, its bonding strength has not yet reached the level required for some specialized applications, and its relatively low mechanical properties limit its application in adhesives that withstand extreme environments, such as high temperatures and solvents. Therefore, there is an urgent need to develop a method for preparing a class of non-isocyanate polyurethanes resistant to extreme environments. Summary of the Invention

[0005] To address the problem of poor resistance to extreme environments in existing adhesives, this invention provides a non-isocyanate polyurethane adhesive resistant to extreme environments and its preparation method.

[0006] In a first aspect, the present invention provides a method for preparing an extreme environment resistant non-isocyanate polyurethane adhesive, wherein a diglycidyl ether intermediate is synthesized from a phenolic compound containing a rigid group as a raw material, and then reacted with carbon dioxide to obtain a five-membered cyclic carbonate monomer, and finally reacted with a flexible segment amine compound and a rigid segment amine compound to obtain the aforementioned extreme environment resistant non-isocyanate polyurethane adhesive.

[0007] The phenolic compound containing a rigid group is selected from one of magnolol, resveratrol, and genistein;

[0008] The flexible segment amine compound is selected from ternary amine compounds containing polyether structures or long-chain diamine compounds with a molecular weight of 400-600; the rigid segment amine compound is selected from short-chain ternary amine compounds with a molecular weight of 100-200 or diamine compounds containing a six-membered aliphatic ring.

[0009] Furthermore, the flexible segment amine compound is selected from at least one of Priamine 1074, Priamine 1075, and polyetheramine T403, and the rigid segment amine compound is selected from at least one of 1,8-diamino-p-menthane (MDA), isophorone diamine (IPDA), and tris(2-aminoethyl)amine (TAEA).

[0010] Furthermore, the molar amount of amino groups in the flexible segment amine compound accounts for 20%-95% of the total molar amount of amino groups in both the flexible segment amine compound and the rigid segment amine compound.

[0011] Furthermore, the molar ratio of the cyclic carbonate in the five-membered cyclic carbonate monomer to the total amount of amino groups in the flexible segment amine compound and the rigid segment amine compound is 1:1.

[0012] Furthermore, the phenolic compound containing the rigid group is magnolol, the flexible segment amine compound is selected from triamine compounds with a molecular weight of 400-600 containing a polyether structure, and the rigid segment amine compound is selected from short carbon chain triamine compounds with a molecular weight of 100-200.

[0013] Furthermore, it includes the following steps:

[0014] S1. A phenolic compound containing a rigid group is reacted with epichlorohydrin under the action of a first catalyst and stirred. Then, an aqueous solution of sodium hydroxide is added to continue the reaction to obtain a diglycidyl ether intermediate.

[0015] S2. The diglycidyl ether intermediate prepared in step S1 is dissolved in a solvent along with the second catalyst and the co-catalyst. The mixture is placed in a high-pressure reactor and reacted under CO2 conditions to obtain a five-membered cyclic carbonate monomer.

[0016] S3. The five-membered cyclic carbonate monomer prepared in step S2 is dissolved in a solvent in proportion with flexible segment amine compounds and rigid segment amine compounds for prepolymerization reaction. After post-treatment, an extreme environment resistant non-isocyanate polyurethane adhesive is obtained.

[0017] Further, the first catalyst in step S1 is at least one of benzyltriethylammonium chloride, tetrabutylammonium chloride, and tetrabutylammonium bromide.

[0018] Furthermore, the molar ratio of the phenolic hydroxyl content in the rigid-group phenolic compound to the first catalyst is 1:0.05-0.1; the molar ratio of the phenolic hydroxyl content in the rigid-group phenolic compound to epichlorohydrin is 1:20-25; and the molar ratio of the phenolic hydroxyl content in the rigid-group phenolic compound to sodium hydroxide is 1:1-1.2.

[0019] Furthermore, in step S1, the stirring reaction conditions are 80-100℃ for 2-4 hours, then cooled to room temperature, and 40wt% sodium hydroxide aqueous solution is added through a constant pressure funnel to continue the reaction for 1-12 hours.

[0020] Furthermore, the second catalyst in step S2 is one of tetrabutylammonium iodide, tetrabutylammonium bromide, and tetrabutylammonium chloride, and the co-catalyst is L-ascorbic acid; the solvent is one of N-methylpyrrolidone, acetone, and butanone.

[0021] Furthermore, the molar ratio of the epoxy group of the diglycidyl ether intermediate to the second catalyst is 1:0.02-0.04, and the molar ratio of the epoxy group of the diglycidyl ether intermediate to the co-catalyst is 1:0.01-0.02.

[0022] Furthermore, the reaction conditions in step S2 are a pressure of 2-4 MPa and a reaction temperature of 80°C for 24-48 hours.

[0023] Furthermore, the prepolymerization reaction conditions in step S3 are 70-90℃ for 1-3 hours.

[0024] Further, the solvent in step S3 is at least one of anhydrous chloroform, anhydrous dimethylacetamide (DMAc), anhydrous dimethylformamide (DMF), and anhydrous dimethyl sulfoxide (DMSO).

[0025] Furthermore, the post-treatment of diglycidyl ether in step S1 is as follows: after washing with water, the organic phase is retained, and then dried with anhydrous magnesium sulfate, filtered, rotary evaporated, and vacuum dried.

[0026] Further, after the reaction in step S2 is completed, the organic phase is retained after washing with water and filtering to obtain the five-membered cyclic carbonate monomer.

[0027] Furthermore, the post-processing method of step S3 is as follows: the reacted mixture is transferred to a polytetrafluoroethylene mold to evaporate the solvent and then solidify.

[0028] Furthermore, the curing reaction conditions in step S3 are: evaporation of solvent at 50-70℃ for 12-24 hours, further evaporation of solvent at 90-100℃ and curing for 12-24 hours, and curing at 150℃ for 12-24 hours.

[0029] Secondly, this invention discloses a type of non-isocyanate polyurethane adhesive resistant to extreme environments, prepared using the method described above. Its resistance to extreme environments is as follows: the lap shear strength of the bonded Al reaches 16.7 MPa; the lap shear strength reaches 15.6 MPa at a low temperature of -196℃; the lap shear strength reaches 15.2 MPa at a high temperature of 190℃; and after the bonded sample is immersed in a solvent for 24 hours, the lap shear strength still remains above 15.4 MPa, reaching 16.5 MPa.

[0030] The materials prepared by this invention can be applied in the field of aerospace equipment, maintaining the normal operation of electronic devices in high-altitude and low-temperature environments. They ensure stable connections between components in extreme temperature environments, guaranteeing flight safety. They can also be applied to medical devices, used in the manufacture of medical equipment and instruments that require frequent sterilization or exposure to chemical reagents, ensuring the stability of bonded areas. Furthermore, they can be used in chemical product packaging, for packaging products that come into contact with solvents, ensuring that the packaging materials do not deteriorate due to solvent contact during transportation and storage.

[0031] Beneficial effects:

[0032] 1. The synthesis method of this invention is simple, and the reaction conditions are easy to control. By preparing cyclic carbonate monomers containing rigid structures, selecting the types of di / polyamines, and adjusting the ratio of flexible segment amine compounds to rigid amine compounds, a non-isocyanate polyurethane adhesive with excellent mechanical properties is prepared, achieving controllable bonding strength and resistance to extreme environments. The introduction of rigid structures not only enhances the cohesive energy of the material but also improves its solvent resistance. The rigid structure makes the molecular chains more difficult to rotate and bend, resulting in a more compact arrangement between the molecular chains. Due to the smaller gaps between the molecular chains, solvent molecules have difficulty penetrating into the material, thereby improving the material's solvent resistance. A portion of the prepared material's molecular structure consists of soft segments (containing carbon-carbon bonds, ether bonds, etc. in the main chain), exhibiting good flexibility. The synergistic effect of these segments and the rigid groups in the structure achieves a high-performance adhesive with excellent bonding strength and resistance to extreme environments.

[0033] 2. The non-isocyanate polyurethane adhesive provided by this invention exhibits superior performance by generating more interactions with the substrate surface through abundant hydrogen bonds and polar groups, combined with the material's inherent high cohesive energy. This material possesses excellent tensile strength, lap shear strength, high and low temperature resistance, and solvent resistance. Specifically, the lap shear strength when bonding aluminum reaches 16.7 MPa; after treatment at a low temperature (-196℃) for 24 hours, the lap shear strength reaches 15.6 MPa; and after treatment at a high temperature (190℃) for 30 minutes, the lap shear strength reaches 15.2 MPa. After immersion in solvents (acetone, DMF, diethyl ether, ethyl acetate, n-hexane, tetrahydrofuran, toluene) for 24 hours, the lap shear strength of the bonded samples still remains above 15.4 MPa, reaching 16.5 MPa. Attached Figure Description

[0034] Figure 1 The MAG-T403 prepared in Example 2 30 MDA 70 Infrared spectrum;

[0035] Figure 2 RE-1074 obtained in Example 5 70 MDA 30 Infrared spectrum;

[0036] Figure 3 The Gen-1075 prepared in Example 8 80 IPDA 20 Infrared spectrum;

[0037] Figure 4 RE-1074 obtained in Example 5 70 MDA 30 The stretch shear diagram. Detailed Implementation

[0038] To better understand the above-mentioned objectives, features, and advantages of the present invention, the solutions of the present invention will be further described below. It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other. Many specific details are set forth in the following description to provide a thorough understanding of the present invention, but the present invention can also be implemented in other ways different from those described herein; obviously, the embodiments in the specification are only some embodiments of the present invention, and not all embodiments.

[0039] The preferred embodiments of the present invention will now be described in detail with reference to specific examples. It should be understood that the following examples are given for illustrative purposes only and are not intended to limit the scope of the invention. Those skilled in the art can make various modifications and substitutions to the present invention without departing from its spirit and essence.

[0040] Unless otherwise specified, the experimental and calculation methods used in the following embodiments are conventional methods. Unless otherwise specified, the materials and reagents used in the following embodiments are commercially available. The performance testing instrument used in the embodiments of this invention is a Fourier transform infrared spectrometer for microstructure analysis.

[0041] To test its performance as an adhesive, aluminum was chosen as the bonding material. Before bonding, the aluminum was sanded smooth. Then, NIPU material was cut into rectangles (25 × 12.5 × 0.1 mm) and placed between two identical substrates (100 × 25 × 2 mm), with an overlap area of ​​25 mm × 12.5 mm. This sandwich-shaped sample was then hot-pressed in a hot press (190 °C, 10 min, 0.5 MPa). After cooling to room temperature and standing for 12 hours, a uniaxial tensile test was performed at 20 °C with a strain rate of 5 mm / min to determine the overlap shear strength. Tensile shear strength tests were conducted according to GB / T 7124-2008 to evaluate its adhesive strength.

[0042] High temperature resistant test specimens: The bonded specimens were heated to 190°C with a hot air gun for 30 minutes, and then the tensile bond strength was tested.

[0043] Low-temperature test specimens: The bonded specimens were placed in liquid nitrogen for 24 hours, and then the tensile bond strength was tested.

[0044] Solvent-resistant test specimens: The bonded specimens are immersed in an organic solvent for 24 hours, and then the tensile bond strength is tested.

[0045] Example 1

[0046] (1) Preparation of magnolol epoxy resin (MAG-EP)

[0047] Honokiol (20 g, 75.2 mmol, 1 eq) and benzyltriethylammonium chloride (3.4 g, 14.9 mmol, 0.1 eq) were added to a 500 mL three-necked flask under a nitrogen atmosphere. Then epichlorohydrin (276.6 g, 3006.5 mmol, 40 eq) was added, and the mixture was heated to 80 °C to form a clear solution. The mixture was stirred and reacted for 4 h.

[0048] The temperature was then lowered to room temperature, and 40 wt% NaOH solution (11.8 mL, 165.4 mmol, 2.2 eq) was added dropwise using a constant pressure funnel. After reacting for 1 h, the mixture was filtered to remove salt, washed three times with water, and the organic phase was collected. Anhydrous magnesium sulfate was then added and dried. The mixture was filtered, and epichlorohydrin was removed by rotary evaporation. The product was then dried under vacuum at 60 °C for 24 h to obtain a white powder. The yield was 94%.

[0049] (2) Preparation of magnolol five-membered cyclic carbonate (MAG-BCC)

[0050] MAG-EP (20 g, 52.9 mmol, 1 eq), tetrabutylammonium iodide (0.78 g, 2.1 mmol, 0.04 eq), and L-ascorbic acid (0.19 g, 1.08 mmol, 0.02 eq) were dissolved in acetone and added to a high-pressure reactor. CO2 was introduced at 2 MPa, and the reaction was carried out at 80 °C for 24 h. After the reaction was completed, the reaction solution was added dropwise to deionized water, stirred overnight, washed three times with water, and then freeze-dried for 24 h to obtain MAG-BCC. The yield was 91%.

[0051] (3) Preparation of magnolol non-isocyanate polyurethane (MAG-PHU)

[0052] The molar ratio of amino to cyclic carbonate was controlled at 1:1, with the amino content of rigid-chain amines accounting for 80% of the total content. MAG-BCC (0.5 g, 1.1 mmol, 1 eq), TAEA (0.086 g, 0.59 mmol, 0.53 eq), and Priamine 1075 (0.12 g, 0.22 mmol, 0.2 eq) were added to a single-necked flask, dissolved in anhydrous chloroform and anhydrous DMAc, prepolymerized at 80 °C for 3 h, then poured into a polytetrafluoroethylene mold, and volatilized at 50 °C for 12 h, cured at 90 °C for 24 h, and cured at 150 °C for 24 h, respectively, to obtain MAG-TAEA. 80 1075 20 .

[0053] Example 2

[0054] (1) Preparation of magnolol epoxy resin (MAG-EP)

[0055] Same as Example 1(1).

[0056] (2) Preparation of magnolol five-membered cyclic carbonate (MAG-BCC)

[0057] Same as Example 1(2).

[0058] (3) Preparation of magnolol non-isocyanate polyurethane (MAG-PHU)

[0059] The molar ratio of amino to cyclic carbonate was controlled at 1:1, and the amino content of rigid-chain amines accounted for 70% of the total content. MAG-BCC (0.5 g, 1.1 mmol, 1 eq), T403 (0.097 g, 0.22 mmol, 0.2 eq), and MDA (0.13 g, 0.77 mmol, 0.7 eq) were added to a single-necked flask, dissolved in anhydrous chloroform and anhydrous DMAc, prepolymerized at 80°C for 3 h, then poured into a polytetrafluoroethylene mold, and volatilized at 50°C for 12 h, cured at 90°C for 24 h, and cured at 150°C for 24 h, respectively, to obtain MAG-T403. 30 MDA 70 .

[0060] Example 3

[0061] (1) Preparation of magnolol epoxy resin (MAG-EP)

[0062] Same as Example 1(1).

[0063] (2) Preparation of magnolol five-membered cyclic carbonate (MAG-BCC)

[0064] Same as Example 1(2).

[0065] (3) Preparation of magnolol non-isocyanate polyurethane (MAG-PHU)

[0066] The molar ratio of amino to cyclic carbonate was controlled at 1:1, and the amino content of rigid-chain amine accounted for 20% of the total content. MAG-BCC (0.5 g, 1.1 mmol, 1 eq), T403 (0.258 g, 0.59 mmol, 0.53 eq), and IPDA (0.037 g, 0.22 mmol, 0.2 eq) were added to a single-necked flask, dissolved in anhydrous chloroform and anhydrous DMAc, prepolymerized at 80°C for 3 h, then poured into a polytetrafluoroethylene mold, and volatilized at 50°C for 12 h, cured at 90°C for 24 h, and cured at 150°C for 24 h, respectively, to obtain MAG-T403. 80 IPDA 20 .

[0067] Example 4

[0068] (1) Preparation of resveratrol epoxy resin (RE-EP)

[0069] Resveratrol (20 g, 87.7 mmol, 0.3 eq) and tetrabutylammonium chloride (3.65 g, 13.1 mmol) were added to a 500 mL three-necked flask under a nitrogen atmosphere. Then epichlorohydrin (605 g, 6576.1 mmol, 75 eq) was added, and the mixture was heated to 90 °C to form a clear solution. The mixture was stirred and reacted for 3 h.

[0070] The temperature was then lowered to room temperature, and 40 wt% NaOH solution (24.4 mL, 342.0 mmol, 3.9 eq) was added dropwise using a constant pressure funnel. After reacting for 1 h, the mixture was filtered to remove salt, washed three times with water, and the organic phase was collected. Anhydrous magnesium sulfate was then added and dried. The mixture was filtered, and epichlorohydrin was removed by rotary evaporation. The product was then dried under vacuum at 60 °C for 24 h to obtain a white powder. The yield was 93%.

[0071] (2) Preparation of resveratrol pentaneous cyclic carbonate (RE-TCC)

[0072] RE-EP (20 g, 50.5 mmol, 1 eq), tetrabutylammonium bromide (1.95 g, 6.0 mmol, 0.12 eq), and L-ascorbic acid (0.53 g, 3.01 mmol, 0.06 eq) were dissolved in acetone and added to a high-pressure reactor. CO2 was introduced at 3 MPa, and the reaction was carried out at 100 °C for 12 h. After the reaction was completed, the reaction solution was added dropwise to deionized water, stirred overnight, washed three times with water, and then freeze-dried for 24 h to obtain RE-TCC. The yield was 92%.

[0073] (3) Preparation of resveratrol-based non-isocyanate polyurethane (RE-PHU)

[0074] The molar ratio of amino to cyclic carbonate was controlled at 1:1, and the amino content of rigid-chain amines accounted for 10% of the total content. RE-BCC (0.5 g, 0.947 mmol, 1 eq), Priamine 1074 (0.683 g, 1.28 mmol, 1.35 eq), and IPDA (0.024 g, 0.14 mmol, 0.15 eq) were added to a single-necked flask, dissolved in anhydrous DMF, prepolymerized at 80°C for 3 h, then poured into a polytetrafluoroethylene mold, and volatilized at 70°C for 24 h, cured at 100°C for 12 h, and cured at 150°C for 12 h, respectively, to obtain RE-1074. 90 IPDA 10 .

[0075] Example 5

[0076] (1) Preparation of resveratrol epoxy resin (RE-EP)

[0077] Same as Example 4(1).

[0078] (2) Preparation of resveratrol pentaneous cyclic carbonate (RE-TCC)

[0079] Same as Example 4(2).

[0080] (3) Preparation of resveratrol-based non-isocyanate polyurethane (RE-PHU)

[0081] The molar ratio of amino to cyclic carbonate was controlled at 1:1, and the amino content of rigid-chain amines accounted for 30% of the total content. RE-BCC (0.5 g, 0.947 mmol, 1 eq), Priamine 1074 (0.531 g, 0.994 mmol, 1.05 eq), and MDA (0.073 g, 0.426 mmol, 0.45 eq) were added to a single-necked flask, dissolved in anhydrous DMF, prepolymerized at 80°C for 3 h, then poured into a polytetrafluoroethylene mold, and volatilized at 50°C for 12 h, cured at 90°C for 24 h, and cured at 150°C for 24 h, respectively, to obtain RE-1074. 70 IPDA 30 .

[0082] Example 6

[0083] (1) Preparation of resveratrol epoxy resin (RE-EP)

[0084] Same as Example 4(1).

[0085] (2) Preparation of resveratrol pentaneous cyclic carbonate (RE-TCC)

[0086] Same as Example 4(2).

[0087] (3) Preparation of resveratrol-based non-isocyanate polyurethane (RE-PHU)

[0088] The molar ratio of amino to cyclic carbonate was controlled at 1:1, with the amino content of rigid-chain amines accounting for 80% of the total content. RE-BCC (0.5 g, 0.947 mmol, 1 eq), Priamine 1075 (0.159 g, 0.284 mmol, 0.3 eq), and MDA (0.193 g, 1.136 mmol, 1.2 eq) were added to a single-necked flask, dissolved in anhydrous DMF, prepolymerized at 80°C for 3 h, then poured into a polytetrafluoroethylene mold, and volatilized at 50°C for 12 h, cured at 90°C for 24 h, and cured at 150°C for 24 h, respectively, to obtain RE-1075. 20 MDA 80 .

[0089] Example 7

[0090] (1) Preparation of Gen-EP epoxy resin (gen-EP)

[0091] Gentianone (20 g, 73.9 mmol, 1 eq) and tetrabutylammonium bromide (4.29 g, 13.3 mmol, 0.21 eq) were added to a 500 mL three-necked flask under a nitrogen atmosphere. Then epichlorohydrin (470.1 g, 5109.8 mmol, 69 eq) was added, and the mixture was heated to 100 °C to form a clear solution. The mixture was stirred and reacted for 2 h.

[0092] The temperature was then lowered to room temperature, and 40 wt% NaOH solution (18.1 mL, 266.0 mmol, 3.6 eq) was added dropwise using a constant pressure funnel. After reacting for 1 h, the mixture was filtered to remove salt, washed three times with water, and the organic phase was collected. Anhydrous magnesium sulfate was then added and dried. The mixture was filtered, and epichlorohydrin was removed by rotary evaporation. The product was then dried under vacuum at 60 °C for 24 h to obtain a white powder. The yield was 90%.

[0093] (2) Preparation of genistein five-membered cyclic carbonate (Gen-TCC)

[0094] Gen-EP (20 g, 45.6 mmol, 1 eq), tetrabutylammonium chloride (1.14 g, 4.1 mmol, 0.09 eq), and L-ascorbic acid (0.36 g, 2.0 mmol, 0.045 eq) were dissolved in acetone and added to a high-pressure reactor. CO2 was introduced at 4 MPa, and the reaction was carried out at 90 °C for 20 h. After the reaction was completed, the reaction solution was added dropwise to deionized water, stirred overnight, washed three times with water, and then freeze-dried for 24 h to obtain Gen-TCC. The yield was 92%.

[0095] (3) Preparation of Gen-PHU (genistein-based non-isocyanate polyurethane)

[0096] The molar ratio of amino to cyclic carbonate was controlled at 1:1, and the amino content of rigid-chain amines accounted for 5% of the total content. Gen-BCC (0.5 g, 0.877 mmol, 1 eq), Priamine 1075 (0.700 g, 1.250 mmol, 1.425 eq), and IPDA (0.011 g, 0.066 mmol, 0.075 eq) were added to a single-necked flask, dissolved in anhydrous DMSO, prepolymerized at 80 °C for 3 h, then poured into a polytetrafluoroethylene mold, and volatilized at 60 °C for 16 h, cured at 95 °C for 24 h, and cured at 150 °C for 20 h, respectively, to obtain Gen-1075. 95 IPDA5.

[0097] Example 8

[0098] (1) Preparation of Gen-EP epoxy resin (gen-EP)

[0099] Same as Example 7(1).

[0100] (2) Preparation of genistein five-membered cyclic carbonate (Gen-TCC)

[0101] Same as Example 7(2).

[0102] (3) Preparation of Gen-PHU (genistein-based non-isocyanate polyurethane)

[0103] The molar ratio of amino to cyclic carbonate was controlled at 1:1, and the amino content of rigid-chain amines accounted for 20% of the total content. Gen-BCC (0.5 g, 0.877 mmol, 1 eq), Priamine 1074 (0.563 g, 1.052 mmol, 1.2 eq), and IPDA (0.045 g, 0.263 mmol, 0.3 eq) were added to a single-necked flask, dissolved in anhydrous DMSO, prepolymerized at 80 °C for 3 h, then poured into a polytetrafluoroethylene mold, and volatilized at 50 °C for 12 h, cured at 90 °C for 24 h, and cured at 150 °C for 24 h, respectively, to obtain Gen-1075. 80 IPDA 20 .

[0104] Example 9

[0105] (1) Preparation of Gen-EP epoxy resin (gen-EP)

[0106] Same as Example 7(1).

[0107] (2) Preparation of genistein five-membered cyclic carbonate (Gen-TCC)

[0108] Same as Example 7(2).

[0109] (3) Preparation of Gen-PHU (genistein-based non-isocyanate polyurethane)

[0110] The molar ratio of amino to cyclic carbonate was controlled at 1:1, with the amino content of rigid-chain amines accounting for 70% of the total content. Gen-BCC (0.5 g, 0.877 mmol, 1 eq), Priamine 1074 (0.211 g, 0.395 mmol, 0.45 eq), and MDA (0.157 g, 0.921 mmol, 1.05 eq) were added to a single-necked flask, dissolved in anhydrous DMSO, prepolymerized at 80 °C for 3 h, then poured into a polytetrafluoroethylene mold, and volatilized at 50 °C for 12 h, cured at 90 °C for 24 h, and cured at 150 °C for 24 h, respectively, to obtain Gen-1074. 30 MDA 70 .

[0111] Comparative Example 1

[0112] (1) Preparation of magnolol epoxy resin (MAG-EP)

[0113] Same as Example 1(1).

[0114] (2) Preparation of magnolol five-membered cyclic carbonate (MAG-BCC)

[0115] Same as Example 1(2).

[0116] (3) Preparation of magnolol non-isocyanate polyurethane (MAG-PHU)

[0117] The molar ratio of amino to cyclic carbonate was controlled at 1:1, and the amino content of rigid segment amine accounted for 100% of the total content. MAG-BCC (0.5 g, 1.1 mmol, 1 eq) and TAEA (0.107 g, 0.733 mmol, 0.667 eq) were added to a single-necked flask, dissolved in anhydrous chloroform and anhydrous DMAc, prepolymerized at 80 °C for 3 h, and then poured into a polytetrafluoroethylene mold. After evaporation at 50 °C for 12 h, curing at 90 °C for 24 h, and curing at 150 °C for 24 h, respectively, MAG-TAEA was obtained.

[0118] Comparative Example 2

[0119] (1) Preparation of resveratrol epoxy resin (RE-EP)

[0120] Same as Example 4(1).

[0121] (2) Preparation of resveratrol pentaneous cyclic carbonate (RE-TCC)

[0122] Same as Example 4(2).

[0123] (3) Preparation of resveratrol-based non-isocyanate polyurethane (RE-PHU)

[0124] The molar ratio of amino to cyclic carbonate was controlled at 1:1, and the amino content of rigid segment amine accounted for 0% of the total content. RE-BCC (0.5 g, 0.947 mmol, 1 eq) and Priamine 1075 (0.795 g, 1.420 mmol, 1.5 eq) were added to a single-necked flask, dissolved in anhydrous DMF, prepolymerized at 80 °C for 3 h, and then poured into a polytetrafluoroethylene mold. After evaporation at 50 °C for 12 h, curing at 90 °C for 24 h, and curing at 150 °C for 24 h, respectively, RE-1075 was obtained.

[0125] Comparative Example 3

[0126] (1) Preparation of Gen-EP epoxy resin (gen-EP)

[0127] Same as Example 7(1).

[0128] (2) Preparation of genistein five-membered cyclic carbonate (Gen-TCC)

[0129] Same as Example 7(2).

[0130] (3) Preparation of Gen-PHU (genistein-based non-isocyanate polyurethane)

[0131] The molar ratio of amino to cyclic carbonate was controlled at 1:1, and the amino content of rigid segment amine accounted for 100% of the total content. Gen-BCC (0.5 g, 0.877 mmol, 1 eq) and MDA (0.224 g, 0.315 mmol, 1.5 eq) were added to a single-necked flask, dissolved in anhydrous DMSO, prepolymerized at 80 °C for 3 h, and then poured into a polytetrafluoroethylene mold. After evaporation at 50 °C for 12 h, curing at 90 °C for 24 h, and curing at 150 °C for 24 h, Gen-MDA was obtained.

[0132] Characterization Example 1

[0133] Infrared spectroscopy was performed on the cyclic carbonate monomers in Examples 2, 5, and 8, as well as the prepared NIPU materials. The obtained infrared spectra are shown below. Figure 1 , Figure 2 and Figure 3 Due to the ring-opening of the cyclic carbonate group, the 1795 cm⁻¹ corresponding to C=O... -1 The absorption peak at 1690 cm⁻¹ disappears, and the corresponding infrared spectrum of the prepared NIPU material shows a peak at 1690 cm⁻¹. -1 An absorption peak for C=O was observed at [location missing]. These results demonstrate the successful preparation of the NIPU material.

[0134] Table 1. Overlap shear strength prepared in the examples.

[0135]

[0136] As shown in Table 1, the NIPU adhesive provided by this invention exhibits excellent bonding strength, capable of withstanding extreme environments, with a bonding strength exceeding 9 MPa and reaching up to 16 MPa. It also demonstrates superior bonding performance, excellent resistance to high and low temperatures and solvents, with a low-temperature resistance of -196℃ and a high-temperature resistance of 190℃, and resistance to organic solvents. In both high and low temperature resistance and solvent resistance tests, the material's bonding performance only decreased slightly while maintaining good bonding strength above 9 MPa. In contrast, Comparative Examples 1, 2, and 3 showed lower bonding strength and poorer low-temperature resistance. For example, Comparative Example 3 had a room temperature bonding strength of 10.9 MPa, which decreased to 6.8 MPa after low-temperature testing. This is mainly due to the material's brittleness, high tensile strength but low elongation at break (only 5%), which significantly reduces its low-temperature resistance.

[0137] This is merely a preferred embodiment of the present invention and is not intended to limit the scope of the patent. Any equivalent structural or procedural transformations made using the present invention specification, or any direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. A process for the preparation of an extreme environment resistant non-isocyanate polyurethane adhesive, characterized in that, The application relates to a non-isocyanate polyurethane adhesive resistant to extreme environments, which is synthesized by taking a phenolic compound containing a rigid group as a raw material, synthesizing a diglycidyl ether intermediate, reacting with carbon dioxide to obtain a five-membered ring carbonate monomer, and then reacting with amine compounds of flexible and rigid chain segments. The phenolic compound containing a rigid group is selected from one of magnolol, resveratrol and genistein. The amine compound of the flexible chain segment is selected from one of a three-amine compound containing a polyether structure and having a molecular weight of 400-600 or a long-carbon-chain di-amine compound; the amine compound of the rigid chain segment is selected from one of a short-carbon-chain three-amine compound having a molecular weight of 100-200 or a di-amine compound containing a six-membered aliphatic ring; the molar amount of the amino group in the amine compound of the flexible chain segment accounts for 20-95% of the total molar amount of the amino groups in the amine compound of the flexible chain segment and the amine compound of the rigid chain segment; and the molar ratio of the cyclic carbonate in the five-membered ring carbonate monomer to the total amount of the amino groups in the amine compound of the flexible chain segment and the amine compound of the rigid chain segment is 1:

1.

2. The production method according to claim 1, characterized by, The amine compound of the flexible chain segment is at least one of Priamine 1074, Priamine 1075 and polyether amine T403, and the amine compound of the rigid chain segment is at least one of 1,8-diamino-p-menthane, isophorone diamine and tri(2-aminoethyl)amine.

3. The preparation method according to claim 1, characterized in that, The phenolic compound containing a rigid group is magnolol, the amine compound of the flexible chain segment is a three-amine compound containing a polyether structure and having a molecular weight of 400-600, and the amine compound of the rigid chain segment is a short-carbon-chain three-amine compound having a molecular weight of 100-200.

4. The production method according to any one of claims 1 to 3, characterized by, The method comprises the following steps: S1, stirring and reacting a phenolic compound containing a rigid group with epichlorohydrin under the action of a first catalyst, then adding a sodium hydroxide aqueous solution to continue the reaction, to obtain a diglycidyl ether intermediate; S2, dissolving the diglycidyl ether intermediate prepared in step S1 in a solvent together with a second catalyst and a cocatalyst, placing the mixture in a high-pressure reactor, and reacting under the condition of CO2 input to obtain a five-membered ring carbonate monomer; S3, dissolving the five-membered ring carbonate monomer prepared in step S2 in a solvent together with an amine compound of a flexible chain segment and an amine compound of a rigid chain segment in a certain proportion to pre-polymerize, and then performing post-treatment to obtain the non-isocyanate polyurethane adhesive resistant to extreme environments.

5. The production method according to claim 4, characterized by, The first catalyst in step S1 is at least one of benzyltriethylammonium chloride, tetrabutylammonium chloride and tetrabutylammonium bromide, The second catalyst in step S2 is one of tetrabutylammonium iodide, tetrabutylammonium bromide and tetrabutylammonium chloride, and the cocatalyst is L-ascorbic acid; the solvent is one of N-methylpyrrolidone, acetone and butanone; The solvent in step S3 is at least one of anhydrous chloroform, anhydrous dimethylacetamide, anhydrous dimethylformamide and anhydrous dimethyl sulfoxide.

6. The preparation method according to claim 4, characterized in that, The molar ratio of the phenolic hydroxyl content in the rigid group-containing phenolic compound to the first catalyst is 1:0.05-0.1; the molar ratio of the phenolic hydroxyl content in the rigid group-containing phenolic compound to the epichlorohydrin is 1:20-25, and the molar ratio of the phenolic hydroxyl content in the rigid group-containing phenolic compound to the sodium hydroxide is 1:1-1.2; The molar ratio of the epoxy group in the diglycidyl ether intermediate to the second catalyst is 1:0.02-0.04, and the molar ratio of the epoxy group in the diglycidyl ether intermediate to the cocatalyst is 1:0.01-0.

02.

7. The preparation method according to claim 4, characterized in that, The stirring reaction condition in the step S1 is 80-100℃ for 2-4h, then reduced to room temperature, 40wt% sodium hydroxide aqueous solution is added through a constant pressure funnel, and the reaction is continued for 1-12h; The reaction condition in the step S2 is 2-4MPa, 80℃ for 24-48h; The prepolymerization condition in the step S3 is 70-90℃ for 1-3h.

8. A class of non-isocyanate polyurethane adhesives resistant to extreme environments characterized in that, The preparation method is prepared by using any one of the preparation methods in claims 1-3, 5-7. The preparation method is prepared by using any one of the preparation methods in claims 1-3, 5-7.

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