High-strength two-component polyurethane adhesive and preparation method thereof

Abstract

The invention discloses a high-strength two-component polyurethane adhesive and a preparation method thereof, the adhesive is composed of a component A and a component B, and the volume ratio of the component A to the component B is 1: 1; the component A is prepared from the following raw materials in parts by weight: 12 to 40 parts of polyester polyol, 3 to 20 parts of polyether polyol, 10 to 40 parts of bio-based polyol, 0 to 10 parts of a plasticizer, 0.05 to 0.2 part of a catalyst, 0.5 to 1.5 parts of a defoaming agent, 1 to 7 parts of a 4A molecular sieve and 30 to 55 parts of calcium carbonate. According to the high-strength two-component polyurethane adhesive and the preparation method thereof, a controllable polyhydroxy compound is prepared from epoxy resin to synthesize a polyurethane prepolymer, and the compound is high in crosslinking density and contains an epoxy group, so that the shearing strength and the tensile strength of a traditional polyurethane adhesive can be improved.

Description

Technical Field

[0001] The invention relates to the technical field of adhesives, and in particular to a high-strength two-component polyurethane adhesive and a preparation method thereof. Background Art

[0002] Two-component polyurethane adhesives are mainly composed of isocyanate-terminated prepolymers as the curing agent component, and the other component is a full polyether or oil-based mixture; there are also hydroxyl-terminated prepolymers, and the other component is an isocyanate group as the curing agent. When preparing two-component polyurethane adhesive products, the mass ratio of the components can be adjusted according to the desired effect. In order to achieve complete curing, the isocyanate content is usually slightly excessive.

[0003] Two-component polyurethane adhesives are mainly solvent-free, with 100% solid content and no solvent volatilization; they have good initial adhesion; the ratio of the two components can be adjusted according to the usage; they can be cured at room temperature or at elevated temperatures. However, traditional polyurethane adhesives have a series of disadvantages, such as not being resistant to high temperatures, not being resistant to aging due to humidity and heat, and insufficient bonding strength; therefore, composite epoxy modification is required to prepare high-strength polyurethanes. Epoxy resins have the advantages of high bonding strength and resistance to humidity and heat, and if the two form an interpenetrating network structure, the performance of polyurethane can be improved.

[0004] In the prior art, many scholars have also begun to carry out composite modification through different methods. For example, Chinese patent CN118406458A discloses a solvent-free one-component polyurethane adhesive for woodworking building materials and its use method, which describes the use of a small amount of hydroxyl groups on epoxy resin to react epoxy resin with isocyanate and polyol as a prepolymer to prepare a one-component PUR, and the composite modification is limited. Of course, there are also interesting composite methods in grouting materials. Chinese patent CN108276550B discloses a soybean oil-based polyurethane / epoxy resin grouting material and its preparation method. The A component of this scheme is epoxy resin + soybean oil prepolymer, and the B component is epoxy curing agent + chain extender. The epoxy and polyurethane are cured simultaneously to form an interpenetrating structure, but the reaction speed is fast and uncontrollable. Chinese patent CN117777932A discloses an epoxy hybrid hyperbranched polyurethane adhesive and a preparation method thereof. The reaction of this scheme is relatively complicated, requiring amine and epoxy to react first, then adding monofunctional epoxy / secondary amine to react, and then reacting with isocyanate after dehydration. A total of three steps are required to complete the preparation of polyhydroxy core hyperbranched polyurethane, and a small amount of solvent needs to be added during the reaction process; the highest tensile strength in the embodiment is only 2.05Mpa. Therefore, it is necessary to simplify the preparation process of polyhydroxy compounds to achieve solvent-free addition and high-strength two-component polyurethane adhesive. Summary of the invention

[0005] In view of the problems existing in the prior art, the present invention provides a high-strength two-component polyurethane adhesive and a preparation method thereof.

[0006] In order to achieve the above object, the present invention provides a high-strength two-component polyurethane adhesive, the adhesive is composed of two components A and B, and the volume ratio of component A to component B is 1:1;

[0007] The A component is prepared from the following raw materials in parts by weight:

[0008] 12-40 parts by weight of polyester polyol, 3-20 parts by weight of polyether polyol, 10-40 parts by weight of bio-based polyol, 0-10 parts by weight of plasticizer, 0.05-0.2 parts by weight of catalyst, 0.5-1.5 parts by weight of defoamer, 1-7 parts by weight of 4A molecular sieve, 30-55 parts by weight of calcium carbonate;

[0009] The B component is prepared from the following raw materials in parts by weight:

[0010] 1-15 parts by weight of aliphatic amine curing agent, 10-30 parts by weight of aromatic epoxy resin, 35-120 parts by weight of polyester polyol, 100-140 parts by weight of isocyanate compound, and 25-50 parts by weight of calcium carbonate.

[0011] Preferably, the polyester polyol of component A and the polyester polyol of component B are selected from one or more of Cargill Biotech's pripol 2033, pripol 2043, priplast 1838, priplast 1900, Huada Chemical's CMA-44, T24, T-4420, and Hunan Juren Chemical's 2044, 3057.

[0012] Preferably, the polyether polyol is selected from one or more of Bluestar Dongda DL-2000D, NRC-2000, DL-2000E, DL-1000, and MN-1000E.

[0013] Preferably, the bio-based polyol is selected from one or more of Ito Oil H368, AC-006, AC-009, Zhangjiagang Feihang Technology FH-3140, FH-3170.

[0014] Preferably, the plasticizer is selected from one or more of tricresyl phosphate, triethyl phosphate, toluene diphenyl phosphate, and isopropylated triphenyl phosphate;

[0015] The defoaming agent is selected from at least one of BYK-088, BYK-066N, BYK-A 530 and BYK-1790 produced by BYK Chemical.

[0016] Preferably, the catalyst is selected from one or more of dibutyltin dilaurate, stannous octoate, and dibutyltin diacetate;

[0017] The calcium carbonate of component A and the calcium carbonate of component B are both selected from one or more of heavy calcium carbonate GR-601, GR-603, GR-1500 and light calcium carbonate produced by Jiangxi Bairui Calcium Carbonate.

[0018] Preferably, the fatty amine curing agent is a 1-4-functional amine curing agent, preferably a 1-2-functional curing agent, and the 1-4-functional amine curing agent is selected from one or more of 1,6-hexanediamine, trimethylhexanediamine, KH-550, diethylaminopropylamine, diethylenetriamine, and triethylenetetramine.

[0019] Preferably, the aromatic epoxy resin is a 2-4 functional epoxy resin, preferably a 2-3 functional epoxy resin, and the 2-4 functional epoxy resin is selected from one or more of Tiantai Chemical TT310, TT410, bisphenol A novolac epoxy resin, Huayi resin EBA-75, AG-80, AG70, AG601, and AFG90.

[0020] Preferably, the isocyanate compound is selected from toluene diisocyanate, liquefied MDI, and polymethylene polyphenyl polyisocyanate.

[0021] The present invention also provides a method for preparing the high-strength two-component polyurethane adhesive, which is characterized by comprising the following steps:

[0022] Step S1: Preparation of component A of polyurethane adhesive:

[0023] Step S101: 12-40 parts by weight of polyester polyol, 3-20 parts by weight of polyether polyol, 10-40 parts by weight of bio-based polyol, and 0-10 parts by weight of plasticizer are uniformly mixed, and then subjected to vacuum stirring and dehydration treatment at 100-130° C. for 2-4 hours;

[0024] Step S102: Cooling the treated mixture to 50-60° C., then adding 0.05-0.2 parts by weight of a catalyst, 0.5-1.5 parts by weight of a defoamer, 1-7 parts by weight of a 4A molecular sieve, and 30-55 parts of calcium carbonate treated by dehydration at 100-130° C. for 2-4 hours, mixing evenly, and vacuum degassing to obtain component A;

[0025] Step S2: Preparation of polyurethane adhesive component B:

[0026] Step S201, preparation of polyhydroxy compound: 1-15 parts by weight of aliphatic amine curing agent and 10-30 parts by weight of aromatic epoxy resin are added into a reaction kettle, reacted at room temperature for 2-4 hours, and then heated to 80°C and maintained for 2-4 hours to ensure complete reaction, and the obtained controllable polyhydroxy compound A1 is a yellow or orange slightly viscous liquid;

[0027] Step S201: 7-18 parts by weight of the controllable polyhydroxy compound A1 and 35-120 parts by weight of a polyester polyol with a molecular weight of 2000 are subjected to vacuum stirring and dehydration at 100-130° C. for 2-4 hours, then cooled to 80-90° C., 100-140 parts by weight of an isocyanate compound are added, and reacted for 2-4 hours to obtain an isocyanate prepolymer A2;

[0028] Step S203: finally, 50-75 parts by weight of isocyanate prepolymer A2 and 25-50 parts by weight of dehydrated calcium carbonate II are mixed evenly, and vacuum degassing is performed to obtain component B;

[0029] Step S3: Mix component A and component B in a volume ratio of 1:1 to obtain a high-strength two-component polyurethane adhesive.

[0030] Preferably, there are many preparation routes for the controllable polyhydroxy compounds, and improper combination of aromatic epoxy resin and aliphatic amine curing agent is easy to form a dense network structure, forming a colloid or semi-solid state, for details, please refer to the attached Figure 1 , 2 In addition, in the preparation of isocyanate prepolymer A2, the large difference in the amount of 2000 molecular weight polyester polyol used is caused by the different NCO contents of isocyanate.

[0031] The technical solution of the present invention has the following beneficial effects:

[0032] The invention provides a high-strength two-component polyurethane adhesive and a preparation method thereof. A controllable polyhydroxy compound is prepared by using epoxy resin to synthesize a polyurethane prepolymer. The compound has a high crosslinking density and contains epoxy groups, and can improve the shear strength and tensile strength of traditional polyurethane adhesives.

[0033] The present invention can control the hydroxyl value and viscosity by controlling the ratio of epoxy resins with different functionalities and the ratio of fatty amines with different numbers of primary amines to obtain a polyhydroxy compound, and can also increase the crosslinking density, form a network structure, and increase the tensile strength and shear strength; only a part of the polyhydroxy compound reacts, and the epoxy group is still retained, which has a promoting effect on the shear strength; the polyhydroxy compound is connected to the isocyanate prepolymer, and the overall cohesive strength can also be increased.

[0034] The present invention has high-strength performance: by using a polyhydroxy compound A1 prepared by a specific fatty amine curing agent and an aromatic epoxy resin, and an isocyanate prepolymer A2 prepared by a specific polyester polyol and an isocyanate compound, the high-strength two-component polyurethane adhesive of the present invention exhibits excellent tensile strength and shear strength, meeting the demand for high-strength adhesives in industrial applications.

[0035] The adhesive properties of the present invention can be improved: Due to the unique structure of the polyol A1 and the isocyanate prepolymer A2, the adhesive of the present invention exhibits excellent bonding properties to a variety of substrates, especially metals and plastics.

[0036] The present invention forms an interpenetrating network structure by combining epoxy resin with isocyanate prepolymer. This innovative structural design significantly improves the cohesive strength and durability of the adhesive.

[0037] The adhesive of the present invention is a solvent-free formula with 100% solid content and no solvent volatilization, which is beneficial to environmental protection and the health of operators. By adjusting the proportion of each component, the performance of the adhesive can be customized according to different application requirements, providing good flexibility.

[0038] The present invention has excellent anti-aging performance: due to the introduction of epoxy resin, the adhesive of the present invention exhibits good resistance to moisture and heat aging and is suitable for applications exposed to harsh environments for a long time.

[0039] Compared with the prior art, the preparation process of the present invention is simpler, no additional solvent needs to be added, and production costs and environmental risks are reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 The present invention is an experimental structure diagram of aromatic epoxy resins and aliphatic amines with different functionalities;

[0041] Figure 2 The present invention is a schematic diagram of the ring-opening reaction of epoxy group and primary amine. DETAILED DESCRIPTION

[0042] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0043] Example 1

[0044] Reference Figure 1 to Figure 2 The present invention provides a high-strength two-component polyurethane adhesive and a preparation method thereof, and the specific steps are as follows:

[0045] Step 1: Preparation of polyols:

[0046] 22g KH-550 and 172g AFG-90 were added to the reactor, stirred at room temperature for 2-4h, and then stirred at 80°C for 2-4h to ensure complete reaction. The obtained product was an orange slightly viscous liquid polyol A1;

[0047] Step 2: Preparation of component A of polyurethane adhesive:

[0048] 20g of Juren Chemical's 2044, 8g of Cargill Bio-priplast 1900, 30g of Ito Oil H368, and 2 parts of toluene diphenyl phosphate plasticizer were placed at 100-130°C for vacuum stirring and dehydration for 2-4h, cooled to 50-60°C, 0.05g of stannous octoate, 0.5g of defoamer BYK-066N, 5 parts of 4A molecular sieves, and 34.45g of calcium carbonate dehydrated at 100-130°C for 2-4h were added, mixed evenly, and vacuum degassed to obtain component A;

[0049] Step 3: Preparation of component B of polyurethane adhesive:

[0050] 20g of the polyol A1 prepared in step 1 and 37.9g ​​of Cargill Bio-priplast 1900 are placed in a reactor, and dehydrated by vacuum stirring at 100-130°C for 2-4h. After cooling to 80-90°C, 100g of liquefied MDI is added, and the reaction is continued for 2-4h to obtain isocyanate prepolymer A2. 60 parts of isocyanate prepolymer A2 are placed in a reactor, and 40 parts of dehydrated calcium carbonate are added, and the mixture is mixed evenly, and vacuum degassing is performed to obtain component B.

[0051] Step 4: Mix the polyurethane A / B components in a volume ratio of 1:1 to obtain a high-strength epoxy-modified two-component polyurethane adhesive.

[0052] Example 2

[0053] Step 1: Preparation of polyols:

[0054] 28g of diethylaminopropylamine, 80g of EPA-75 and 102g of AFG-90 were added to the reactor, stirred at room temperature for 2-4h, and then stirred at 80°C for 2-4h to ensure complete reaction. The obtained product was a light yellow liquid A1 polyol compound;

[0055] Step 2: Preparation of component A of polyurethane adhesive:

[0056] 15 parts of 3057 of Juren Chemical, 10 g of Cargill Bio-priplast 1900, 28 g of Ito Oil AC-006, 5 g of DL-2000D of Bluestar Dongda, and 2 parts of toluene diphenyl phosphate plasticizer, placed at 100-130°C for vacuum stirring and dehydration for 2-4 hours, cooled to 50-60°C, added with 0.05 g of stannous octoate, 0.5 g of defoamer BYK-066N, 3 parts of 4A molecular sieve, and 36.45 g of calcium carbonate dehydrated at 100-130°C for 2-4 hours, mixed evenly, and vacuum degassed to obtain component A;

[0057] Step 4: Preparation of component B of polyurethane adhesive:

[0058] 35g of the polyol A1 obtained in step 1, 19g of T-24 from Huada Chemical, and 19g of Priplast 1900 from Cargill Bio were placed in a reactor, and dehydrated under vacuum stirring at 100-130°C for 2-4h. After cooling to 80-90°C, 100g of liquefied MDI was added, and the reaction was continued for 2-4h to obtain isocyanate prepolymer A2. 65 parts of isocyanate prepolymer A2 were placed in a reactor, and 35 parts of dehydrated calcium carbonate were added, the mixture was mixed evenly, and component B was obtained by vacuum degassing.

[0059] Step 4: Mix the polyurethane A / B components in a volume ratio of 1:1 to obtain a high-strength epoxy-modified two-component polyurethane adhesive.

[0060] Example 3

[0061] Step 1: Preparation of polyols:

[0062] 12 g of diethylaminopropylamine, 9 g of 1,6-hexanediamine, 140 g of EPA-75 and 50 g of AFG-90 were added to the reactor, stirred at room temperature for 2-4 h, and then stirred at 80° C. for 2-4 h to ensure complete reaction. The obtained product was an orange slightly viscous liquid polyol A1;

[0063] Step 2: Preparation of component A of polyurethane adhesive:

[0064] 22g of 2044 from Juren Chemical, 5g of T-4420 from Huada Chemical, 25g of AC-006 from Ito Oil, 5g of DL-2000D from Bluestar Dongda, and 3 parts of toluene diphenyl phosphate plasticizer were placed at 100-130°C for vacuum stirring and dehydration for 2-4h, cooled to 50-60°C, 0.05g of stannous octoate, 0.5g of defoamer BYK-066N, 3 parts of 4A molecular sieves, and 36.45g of calcium carbonate dehydrated at 100-130°C for 2-4h were added, mixed evenly, and vacuum degassed to obtain component A;

[0065] Step 3: Preparation of component B of polyurethane adhesive:

[0066] 17g of the polyol A1 prepared in step 1 and 113.8g of Cargill Bio-priplast 1900 were placed in a reactor, and dehydrated under vacuum stirring at 100-130°C for 2-4h. After cooling to 80-90°C, 100g of toluene diisocyanate was added, and the reaction was continued for 2-4h to obtain isocyanate prepolymer A2. 56 parts of isocyanate A2 were placed in a reactor, and 44 parts of dehydrated calcium carbonate were added. After mixing evenly, the B component was obtained by vacuum degassing.

[0067] Step 4: Mix the polyurethane A / B components in a volume ratio of 1:1 to obtain a high-strength epoxy-modified two-component polyurethane adhesive.

[0068] Comparative Example 1

[0069] Step 1: Preparation of component A of polyurethane adhesive:

[0070] 22g of 2044 from Juren Chemical, 5g of T-4420 from Huada Chemical, 25g of AC-006 from Ito Oil, 5g of DL-2000D from Bluestar Dongda, and 3 parts of toluene diphenyl phosphate plasticizer were placed at 100-130°C for vacuum stirring and dehydration for 2-4h, cooled to 50-60°C, 0.05g of stannous octoate, 0.5g of defoamer BYK-066N, 3 parts of 4A molecular sieves, and 36.45g of calcium carbonate dehydrated at 100-130°C for 2-4h were added, mixed evenly, and vacuum degassed to obtain component A;

[0071] Step 2: Preparation of component B of polyurethane adhesive:

[0072] 30.24g of T-24 from Huada Chemical and 30.24g of Priplast 1900 from Cargill Bio are placed in a reactor, and dehydrated under vacuum stirring at 100-130°C for 2-4h. After cooling to 80-90°C, 100g of liquefied MDI is added, and the reaction is continued for 2-4h to obtain isocyanate prepolymer A2. 56 parts of isocyanate A2 are placed in a reactor, and 44 parts of dehydrated calcium carbonate are added. After mixing evenly, component B is obtained by vacuum degassing.

[0073] Step 3: Mix the polyurethane A / B components in a volume ratio of 1:1 to obtain a high-strength epoxy-modified two-component polyurethane adhesive.

[0074] Comparative Example 2

[0075] Step 1: Preparation of component A of polyurethane adhesive:

[0076] 17g of 2044 from Juren Chemical, 30g of H368 from Ito Oil, 5g of DL-2000D from Bluestar Dongda, and 8 parts of toluene diphenyl phosphate plasticizer were placed at 100-130°C for vacuum stirring and dehydration for 2-4h, cooled to 50-60°C, 0.05g of stannous octoate, 0.5g of defoamer BYK-066N, 3 parts of 4A molecular sieve, and 36.45g of calcium carbonate dehydrated at 100-130°C for 2-4h were added, mixed evenly, and vacuum degassed to obtain component A;

[0077] Step 2: Preparation of component B of polyurethane adhesive:

[0078] 82.36g of Cargill Bio Priplast 1900 is placed in a reactor, and dehydrated under vacuum stirring at 100-130°C for 2-4h. After cooling to 80-90°C, 100g of liquefied MDI is added, and the reaction is continued for 2-4h to obtain isocyanate prepolymer A2. 60 parts of isocyanate A2 are placed in a reactor, and 40 parts of dehydrated calcium carbonate are added. After mixing evenly, component B is obtained by vacuum degassing.

[0079] Step 3: Mix the polyurethane A / B components in a volume ratio of 1:1 to obtain a high-strength epoxy-modified two-component polyurethane adhesive.

[0080] Performance Testing

[0081] The two-component polyurethane adhesives of Examples 1-3 were respectively subjected to performance tests.

[0082] Viscosity test of polyol A1 product: Tested in accordance with ASTM E3116 standard;

[0083] Shear strength test: Tested in accordance with ISO 4587 standard;

[0084] Tensile strength test: Tested in accordance with ASTM D412 standard.

[0085] Table 1 Example test results are as follows:

[0086] Table 1

[0087] project Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 A1 viscosity (mPa·s) 18200 28100 21400 - - Tensile strength(Mpa) 18.3 19.7 18.0 12.6 11.8 Shear strength (AL-AL, Mpa) 15.8 17.4 14.5 10.1 8.6

[0088] It can be seen from Table 1 that the high-strength two-component polyurethane adhesive prepared by the present invention has excellent tensile properties and very high bonding properties to aluminum materials, although the polyhydroxy compound A1 obtained by the reaction of the multifunctional epoxy ring opening and isocyanate has a slightly higher viscosity.

[0089] It can be seen from the above embodiments that the present invention provides a high-strength two-component polyurethane adhesive and a preparation method thereof, which utilizes epoxy resin to prepare a controllable polyhydroxy compound to synthesize a polyurethane prepolymer. The compound has a high cross-linking density and contains epoxy groups, which can improve the shear strength and tensile strength of traditional polyurethane adhesives.

[0090] The present invention can control the hydroxyl value and viscosity by controlling the ratio of epoxy resins with different functionalities and the ratio of fatty amines with different numbers of primary amines to obtain a polyhydroxy compound, and can also increase the crosslinking density, form a network structure, and increase the tensile strength and shear strength; only a part of the polyhydroxy compound reacts, and the epoxy group is still retained, which has a promoting effect on the shear strength; the polyhydroxy compound is connected to the isocyanate prepolymer, and the overall cohesive strength can also be increased.

[0091] The present invention has high-strength performance: by using a polyhydroxy compound A1 prepared by a specific fatty amine curing agent and an aromatic epoxy resin, and an isocyanate prepolymer A2 prepared by a specific polyester polyol and an isocyanate compound, the high-strength two-component polyurethane adhesive of the present invention exhibits excellent tensile strength and shear strength, meeting the demand for high-strength adhesives in industrial applications.

[0092] The adhesive properties of the present invention can be improved: Due to the unique structure of the polyol A1 and the isocyanate prepolymer A2, the adhesive of the present invention exhibits excellent bonding properties to a variety of substrates, especially metals and plastics.

[0093] The present invention forms an interpenetrating network structure by combining epoxy resin with isocyanate prepolymer. This innovative structural design significantly improves the cohesive strength and durability of the adhesive.

[0094] The adhesive of the present invention is a solvent-free formula with 100% solid content and no solvent volatilization, which is beneficial to environmental protection and the health of operators. By adjusting the proportion of each component, the performance of the adhesive can be customized according to different application requirements, providing good flexibility.

[0095] The present invention has excellent anti-aging performance: due to the introduction of epoxy resin, the adhesive of the present invention exhibits good resistance to moisture and heat aging and is suitable for applications exposed to harsh environments for a long time.

[0096] Compared with the prior art, the preparation process of the present invention is simpler, no additional solvent needs to be added, and production costs and environmental risks are reduced.

[0097] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A high-strength two-component polyurethane adhesive, characterized in that: The adhesive is composed of two components, A and B, and the volume ratio of component A to component B is 1:1; The A component is prepared from the following raw materials in parts by weight: 12-40 parts by weight of polyester polyol, 3-20 parts by weight of polyether polyol, 10-40 parts by weight of bio-based polyol, 0-10 parts by weight of plasticizer, 0.05-0.2 parts by weight of catalyst, 0.5-1.5 parts by weight of defoamer, 1-7 parts by weight of 4A molecular sieve, 30-55 parts by weight of calcium carbonate; The B component is prepared from the following raw materials in parts by weight: 1-15 parts by weight of aliphatic amine curing agent, 10-30 parts by weight of aromatic epoxy resin, 35-120 parts by weight of polyester polyol, 100-140 parts by weight of isocyanate compound, and 25-50 parts by weight of calcium carbonate.

2. The high-strength two-component polyurethane adhesive according to claim 1, characterized in that: The polyester polyol in component A and the polyester polyol in component B are selected from one or more of Cargill Bio's pripol 2033, pripol 2043, priplast 1838, priplast 1900, Huada Chemical's CMA-44, T24, T-4420, and Hunan Juren Chemical's 2044, 3057.

3. The high-strength two-component polyurethane adhesive according to claim 1, characterized in that: The polyether polyol is selected from one or more of Bluestar Dongda DL-2000D, NRC-2000, DL-2000E, DL-1000 and MN-1000E.

4. The high-strength two-component polyurethane adhesive according to claim 1, characterized in that: The bio-based polyol is selected from one or more of Ito Oil H368, AC-006, AC-009, Zhangjiagang Feihang Technology FH-3140, FH-3170.

5. The high-strength two-component polyurethane adhesive according to claim 1, characterized in that: The plasticizer is selected from one or more of tricresyl phosphate, triethyl phosphate, toluene diphenyl phosphate, and isopropylated triphenyl phosphate; The defoaming agent is selected from at least one of BYK-088, BYK-066N, BYK-A 530 and BYK-1790 produced by BYK Chemical.

6. The high-strength two-component polyurethane adhesive according to claim 1, characterized in that: The catalyst is selected from one or more of dibutyltin dilaurate, stannous octoate, and dibutyltin diacetate; The calcium carbonate in component A and the calcium carbonate in component B are both selected from one or more of heavy calcium carbonate GR-601, GR-603, GR-1500 and light calcium carbonate produced by Jiangxi Bairui Calcium Carbonate.

7. The high-strength two-component polyurethane adhesive according to claim 1, characterized in that: The fatty amine curing agent is a 1-4-functional amine curing agent, which is selected from one or more of 1,6-hexanediamine, trimethylhexanediamine, KH-550, diethylaminopropylamine, diethylenetriamine, and triethylenetetramine.

8. The high-strength two-component polyurethane adhesive according to claim 1, characterized in that: The aromatic epoxy resin is a 2-4 functional epoxy resin, and the 2-4 functional epoxy resin is selected from one or more of Tiantai Chemical TT310, TT410, bisphenol A novolac epoxy resin, Huayi resin EBA-75, AG-80, AG70, AG601, and AFG90.

9. The high-strength two-component polyurethane adhesive according to claim 1, characterized in that: The isocyanate compound is selected from toluene diisocyanate, liquefied MDI, and polymethylene polyphenyl polyisocyanate.

10. The method for preparing the high-strength two-component polyurethane adhesive according to any one of claims 1 to 9, characterized in that: The steps include: Step S1: Preparation of component A of polyurethane adhesive: Step S101: 12-40 parts by weight of polyester polyol, 3-20 parts by weight of polyether polyol, 10-40 parts by weight of bio-based polyol, and 0-10 parts by weight of plasticizer are uniformly mixed, and then subjected to vacuum stirring and dehydration treatment at 100-130° C. for 2-4 hours; Step S102: Cooling the treated mixture to 50-60° C., then adding 0.05-0.2 parts by weight of a catalyst, 0.5-1.5 parts by weight of a defoamer, 1-7 parts by weight of a 4A molecular sieve, and 30-55 parts of calcium carbonate treated by dehydration at 100-130° C. for 2-4 hours, mixing evenly, and vacuum degassing to obtain component A; Step S2: Preparation of polyurethane adhesive component B: Step S201, preparation of polyhydroxy compound: 1-15 parts by weight of aliphatic amine curing agent and 10-30 parts by weight of aromatic epoxy resin are added into a reaction kettle, reacted at room temperature for 2-4 hours, and then heated to 80°C and maintained for 2-4 hours to ensure complete reaction, and the obtained controllable polyhydroxy compound A1 is a yellow or orange slightly viscous liquid; Step S201: 7-18 parts by weight of the controllable polyhydroxy compound A1 and 35-120 parts by weight of the polyester polyol are subjected to vacuum stirring and dehydration at 100-130° C. for 2-4 hours, then cooled to 80-90° C., 100-140 parts by weight of the isocyanate compound are added, and reacted for 2-4 hours to obtain the isocyanate prepolymer A2; Step S203: finally, 50-75 parts by weight of the A2 prepolymer and 25-50 parts by weight of the dehydrated calcium carbonate II are mixed evenly, and vacuum degassing is performed to obtain component B; Step S3: Mix component A and component B in a volume ratio of 1:1 to obtain a high-strength two-component polyurethane adhesive.

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