Bi-component epoxy graft modified waterborne polyurethane primer as well as preparation method and application thereof

Abstract

The invention provides a two-component epoxy graft modified waterborne polyurethane primer as well as a preparation method and application thereof, and belongs to the technical field of primer. According to the invention, the modified polyurethane curing agent is matched with the amino silane coupling agent and the auxiliary agent, and a synergistic effect with the epoxy graft modified waterborne polyurethane resin is realized, so that the two-component epoxy graft modified waterborne polyurethane primer coating with excellent cohesiveness and aging resistance is obtained, and the bonding requirements of windshields and metal plates in main engine plants and after-sales markets are met.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of primer, and particularly relates to a two-component epoxy grafting modified waterborne polyurethane primer, a preparation method and application thereof. BACKGROUND

[0002] With the rapid development of science and technology, the installation of windshield glass and side window glass in automobile manufacturing and after-sales maintenance has extremely high requirements for safety and reliability, and the traditional mechanical fixing mode is basically replaced by more efficient and firm bonding technology. Polyurethane bonding glue is widely used in the fields of automobiles and rail transit due to its excellent mechanical properties, low-temperature flexibility, durability and other characteristics, especially high-strength one-component moisture-curing polyurethane bonding glue. The high-strength polyurethane bonding glue has poor infiltration and penetration effect on the ceramic glaze of glass and sheet metal, and it is difficult to form a good bonding effect, so it needs to be pretreated with an activator and a primer to achieve excellent bonding and fixing effect. At present, the activators and primers used in the main plant and after-sales maintenance market are mainly based on silane and isocyanate systems, which contain a large amount of organic solvents such as ethanol, low-boiling alkanes, ethyl acetate and butanone. With the increasingly stringent global environmental regulations, automobile manufacturers and the after-sales maintenance market are under pressure to reduce volatile organic compound (VOC) emissions, and harmful volatile substances such as organic solvents and volatile isocyanates have a great impact on the health of workers; at the same time, the NCO in the system has high reactivity and is easily reacted with water vapor in the air, which has high requirements for the storage environment; for low-temperature and low-humidity conditions in winter, the water vapor content in the air is low, and it is difficult for the primer to form a good chemical bond with the substrate and the bonding glue in a short time in a low-temperature environment, which is not conducive to the disassembly of the glass fixture in the main plant and the rapid departure in the after-sales market.

[0003] The prior art discloses an epoxy resin two-component polyurethane adhesive, the A component includes polyurethane grafted epoxy resin, crosslinking agent, active diluent, plasticizer and curing accelerator, and the B component is a mixed curing agent obtained by mixing ethylenediamine and m-phenylenediamine at a mass ratio of 1-2:1. However, the epoxy resin adhesive with ethylenediamine and m-phenylenediamine as the curing agent has high brittleness, the bonding strength needs to be improved, the aging resistance is poor, and it cannot meet the requirements of low-temperature use.

[0004] Therefore, it is of great research significance and application value to develop a two-component epoxy grafting modified waterborne polyurethane primer with excellent adhesion, aging resistance and low-temperature bonding. SUMMARY

[0005] To solve the technical problems in the prior art, the primary object of the present application is to provide a two-component epoxy grafting modified waterborne polyurethane primer, which has excellent adhesion, aging resistance and low-temperature bonding, and meets the requirements of windshield glass and sheet metal bonding in the main plant and after-sales market.

[0006] Still another object of the present application is to provide a preparation method of the above-mentioned two-component epoxy graft-modified waterborne polyurethane primer.

[0007] Still another object of the present application is to provide an application of the above-mentioned two-component epoxy graft-modified waterborne polyurethane primer in automobile glass installation.

[0008] To achieve the above-mentioned objects, the present application adopts the following technical solutions: The present application protects a two-component epoxy graft-modified waterborne polyurethane primer, which comprises the following components in mass fraction: A component: epoxy graft-modified waterborne polyurethane resin 20-30 parts, dispersing agent 0.2-0.5 parts, carbon black 5-8 parts, deionized water 67.5-78.8 parts; B component: modified polyurethane curing agent 80-90 parts, amino silane coupling agent 4-18 parts, curing accelerator 5-10 parts; The modified polyurethane curing agent is prepared by pre-polymerization of hydrophilic polyol and isocyanate, and chain extension of fatty polyamine, and the modified polyurethane curing agent does not contain NCO groups and has a number average molecular weight of 1000-10000. In the modified polyurethane curing agent, the ratio of the total molar amount of hydroxyl groups in the hydrophilic polyol, the total molar amount of cyan acid groups in the isocyanate, and the molar amount of the fatty polyamine is 1:3-3.5:2-2.5; And the total molar amount of cyan acid groups in the isocyanate is equal to the sum of the total molar amount of hydroxyl groups in the hydrophilic polyol and the molar amount of the fatty polyamine. The isocyanate is at least one of diisocyanate or triisocyanate.

[0009] The B component of the two-component epoxy graft-modified waterborne polyurethane primer of the present application introduces polyurethane segments with better flexibility into the modified polyurethane curing agent, reduces the brittleness of the epoxy resin after curing in the primer, and improves the bonding effect and aging resistance. In the modified polyurethane curing agent, one amino group in the aliphatic polyamine reacts with isocyanate, improving the low-temperature bonding property of the primer, and the remaining amino group is the reaction end of the modified polyurethane curing agent, which crosslinks and cures with the epoxy groups in the A component. Therefore, the molar amount of one amino group in the aliphatic polyamine reacts with the remaining cyan acid group in the prepolymer reaction, and the total molar amount of the cyan acid group of the isocyanate is the sum of the total molar amount of the hydroxyl group of the hydrophilic polyol and the molar amount of the aliphatic polyamine. The amino group in the amino silane coupling agent in the B component reacts with the epoxy group in the A component to open the ring, and the siloxane hydrolysis generates silanol, which dehydrates and condenses with the hydroxyl groups on the surface of the substrate to form a chemical bond, improving the water resistance, heat resistance, and moisture resistance in the aging resistance. The obtained primer has excellent adhesion, aging resistance, and low-temperature bonding properties, meeting the requirements of the main engine manufacturers and the aftermarket windshield glass and sheet metal bonding.

[0010] Specifically, the modified polyurethane curing agent without NCO groups is obtained by detecting the disappearance of the NCO infrared peak by an infrared spectrometer.

[0011] Preferably, the weight fraction of the amino silane coupling agent is 5-15 parts.

[0012] Preferably, the hydrophilic polyol is at least one of polycaprolactone diol or polyethylene glycol.

[0013] Preferably, the amino silane coupling agent is at least one of 3-aminopropyl triethoxysilane, N-2-aminoethyl-3-aminopropyl trimethoxysilane, 3-diethylenetriamine propyl trimethoxysilane, N-phenyl-3-aminopropyl trimethoxysilane, or bis(3-trimethoxysilylpropyl)amine.

[0014] Preferably, the isocyanate is at least one of diphenylmethane diisocyanate, toluene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, a triisocyanate is HDI trimer, TDI trimer, IPDI trimer, or HDI biuret.

[0015] Preferably, the mass ratio of the A component and the B component is in the range of 5-10:1.

[0016] Preferably, the aliphatic polyamine is at least one of ethylenediamine, hexanediamine, diethylenetriamine, or triethylenetetramine.

[0017] Preferably, the dispersant is selected according to the prior art and is one or more of an acrylic copolymer, a fatty alcohol polyoxyethylene ether, or a modified waterborne polyurethane.

[0018] More preferably, the dispersant is a polyether siloxane copolymer.

[0019] Preferably, the epoxy grafting modified waterborne polyurethane resin is obtained by adding an epoxy propyl alcohol end-capping agent, a neutralizing agent after a polyester polyol and a diisocyanate prepolymer, hydrophilic chain extension.

[0020] Preferably, the polyester polyol comprises at least one of phthalic anhydride polyester polyol, polycarbonate polyol or polycaprolactone polyol.

[0021] Preferably, the raw material diisocyanate of the epoxy grafting modified waterborne polyurethane resin is at least one of diphenylmethane diisocyanate, toluene diisocyanate, hexamethylene diisocyanate or isophorone diisocyanate.

[0022] Preferably, the hydrophilic chain extension is realized by adding a hydrophilic chain extender, and the hydrophilic chain extender is at least one of 2,2-dimethylol propionic acid or 2,2-dimethylol butyric acid.

[0023] Preferably, the neutralizing agent is triethylamine.

[0024] Preferably, the curing accelerator is at least one of a phenol, a tertiary amine, an organic acid, an acid anhydride or a mercaptan.

[0025] More preferably, the curing accelerator is resorcinol.

[0026] The application also protects the preparation method of the above-mentioned two-component epoxy grafting modified waterborne polyurethane primer, comprising the following steps: S1. Mix an epoxy grafting modified waterborne polyurethane resin emulsion, carbon black and a dispersant to obtain component A; S2. React isocyanate and organic tin catalyst after the hydrophilic polyol and solvent are added to 50±2℃, and the reaction is added to a fatty polyamine solution to obtain a modified polyurethane curing agent; S3. Add the modified polyurethane curing agent prepared in step S2 to a stirring disperser, add an amino silane coupling agent and a curing accelerator to obtain component B of the two-component epoxy grafting modified waterborne polyurethane primer.

[0027] The application of the above-mentioned two-component epoxy grafting modified waterborne polyurethane primer in automobile glass installation is also within the protection scope of the application.

[0028] Preferably, the component A and the component B are mixed uniformly at a mass ratio of 10:1.

[0029] Preferably, the application is the application of the two-component epoxy grafting modified waterborne polyurethane primer with an adhesive.

[0030] Compared with the prior art, the application has the following beneficial effects: The present application provides a two-component epoxy grafting modified waterborne polyurethane primer. The modified polyurethane curing agent is combined with amino silane coupling agent and auxiliary agent, and cooperates with epoxy grafting modified waterborne polyurethane resin to obtain a two-component epoxy grafting modified waterborne polyurethane primer with excellent adhesion, aging resistance and low-temperature bonding, which meets the requirements of main engine manufacturers and after-sales market windshield glass and sheet metal bonding. DETAILED DESCRIPTION

[0031] The present application is further described below in conjunction with examples. These examples are only used to illustrate the present application and are not used to limit the scope of the present application. The experimental methods in the following example embodiments are not specified, and are generally carried out according to conventional conditions or according to the conditions recommended by the manufacturer; the raw materials, reagents, etc. used, if not specifically stated, are all raw materials and reagents that can be obtained through commercial channels such as conventional markets. Any non-essential changes and substitutions made by those skilled in the art based on the present application are within the scope of the present application.

[0032] Some reagents used in the embodiments and comparative examples of the present application are described as follows: Polyester polyol: phthalic anhydride polyester polyol, PN-110, Stepan (Nanjing) Chemical Co., Ltd.; Diisocyanate: diphenylmethane diisocyanate, Wanhua Chemical Group Co., Ltd.; Hydrophilic chain extender: 2,2-dimethylol propionic acid, Shandong Xinghai Chemical Co., Ltd.; 1,4-butanediol, Shandong Ruigang Chemical Co., Ltd.; Blocking agent: epoxy propanol, Jinan Yunuo Chemical Co., Ltd.; Neutralizing agent: triethylamine, Jinan Shuangying Chemical Co., Ltd.; Hydrophilic polyol: polyethylene glycol, PEG-1000, Haian Petrochemical Factory of Jiangsu Province; Triisocyanate: HDI trimer, Covestro (China) Co., Ltd.; Dispersant: polyether siloxane copolymer, 127B, Zhuhai Jintuan Chemical Co., Ltd.; Carbon black: water-based carbon black, S650, Shanghai Lisheng Industry Co., Ltd.; Resorcinol, Shandong Cunfuyuan Chemical Co., Ltd.; Amino silane coupling agent 1#: bis(3-trimethoxysilylpropyl)amine, Hubei Jianghan New Material Co., Ltd.; Amino silane coupling agent 2#: 3-aminopropyl triethoxysilane, Nanjing Nengte New Material Technology Co., Ltd.; Amino silane coupling agent 3#: N-2-aminoethyl-3-aminopropyl trimethoxysilane, Hangzhou Jessica Chemical Co., Ltd.; Silane coupling agent: γ-methacryloxypropyltrimethoxysilane, Nanjing Nengxin New Material Technology Co., Ltd. Fatty polyamine 1#: diethylenetriamine: Nanjing Daze Trading Co., Ltd. Fatty polyamine 2#: ethylenediamine: Jinan Liyan Chemical Co., Ltd. Fatty polyamine 3#: hexamethylene diamine: Jinan Yuanlian Chemical Co., Ltd. Modified polyurethane curing agent 1#: 100 g of hydrophilic polyol PEG-1000 and 100 g of solvent acetone were placed in a reactor, stirred and heated to 50°C, 107.65 g of triisocyanate HDI trimer and 0.01 g of stannous octoate were added, and the reaction was kept at temperature until the NCO content was 6.01%, then cooled to room temperature. The pre-polymer dissolved in acetone was added dropwise into 45.39 g of fatty polyamine 1#: diethylenetriamine, and after the dropwise addition was completed, the reaction was continued until the NCO infrared peak disappeared. The solvent acetone was removed by vacuum distillation to obtain a modified polyurethane curing agent. The ratio of the total moles of hydroxyl groups of the hydrophilic polyol, the total moles of isocyanate cyanate groups, and the moles of fatty polyamine was 1:3.2:2.2, and the molecular weight of the modified polyurethane curing agent was 2200. Modified polyurethane curing agent 2#: the preparation method was the same as that of modified polyurethane curing agent 1#, except that 26.44 g of ethylenediamine was used instead of diethylenetriamine, and the molecular weight of the modified polyurethane curing agent was 2000. Modified polyurethane curing agent 3#: the preparation method was the same as that of modified polyurethane curing agent 1#, except that 51.13 g of hexamethylene diamine was used instead of diethylenetriamine, and the molecular weight of the modified polyurethane curing agent was 2300. Modified polyurethane curing agent 4#: the preparation method was the same as that of modified polyurethane curing agent 1#, except that 100.91 g of triisocyanate HDI trimer and 41.27 g of diethylenetriamine were added, i.e. the ratio of the total moles of hydroxyl groups of the hydrophilic polyol, the total moles of isocyanate cyanate groups, and the moles of fatty polyamine was 1:3:2, and the molecular weight of the modified polyurethane curing agent was 2400. Modified polyurethane curing agent 5#: the preparation method was the same as that of modified polyurethane curing agent 1#, except that 117.73 g of triisocyanate HDI trimer and 51.59 g of diethylenetriamine were added, i.e. the ratio of the total moles of hydroxyl groups of the hydrophilic polyol, the total moles of isocyanate cyanate groups, and the moles of fatty polyamine was 1:3.5:2.5, and the molecular weight of the modified polyurethane curing agent was 1900. Modified polyurethane curing agent 6#: the preparation method was the same as that of modified polyurethane curing agent 1#, except that 55.73 g of toluene diisocyanate was used, and the molecular weight of the modified polyurethane curing agent was 1000.

[0033] Modified polyurethane curing agent 7#: the preparation method is the same as that of modified polyurethane curing agent 1#, the difference is that 100.91 g of triisocyanate HDI trimer and 51.59 g of diethylenetriamine are added, that is, the ratio of the total molar amount of hydroxyl groups of the hydrophilic polyol, the total molar amount of cyanate groups of isocyanate, and the molar amount of fatty polyamine is 1:3:2.5, and the molecular weight of the modified polyurethane curing agent is 1300; Modified polyurethane curing agent 8#: the preparation method is the same as that of modified polyurethane curing agent 1#, the difference is that 117.73 g of triisocyanate HDI trimer and 41.27 g of diethylenetriamine are added, that is, the ratio of the total molar amount of hydroxyl groups of the hydrophilic polyol, the total molar amount of cyanate groups of isocyanate, and the molar amount of fatty polyamine is 1:3.5:2, and the molecular weight of the modified polyurethane curing agent is 7600; Modified polyurethane curing agent 9#: the preparation method is the same as that of modified polyurethane curing agent 1#, the difference is that 67.28 g of triisocyanate HDI trimer and 20.63 g of diethylenetriamine are added, that is, the ratio of the total molar amount of hydroxyl groups of the hydrophilic polyol, the total molar amount of cyanate groups of isocyanate, and the molar amount of fatty polyamine is 1:2:1, and the molecular weight of the modified polyurethane curing agent is 5600; Modified polyurethane curing agent 10#: the preparation method is the same as that of modified polyurethane curing agent 1#, the difference is that 134.56 g of triisocyanate HDI trimer and 61.90 g of diethylenetriamine are added, that is, the ratio of the total molar amount of hydroxyl groups of the hydrophilic polyol, the total molar amount of cyanate groups of isocyanate, and the molar amount of fatty polyamine is 1:4:3, and the molecular weight of the modified polyurethane curing agent is 1800; Curing agent 4#: diethylenetriamine; Curing agent 5#: the preparation method is the same as that of modified polyurethane curing agent 1#, the difference is that 43.26 g of aromatic polyamine p-phenylenediamine is used instead of diethylenetriamine; Curing agent 6#: amino-terminated polyurethane resin curing agent SL-103A.

[0034] 1. Experimental method Preparation method of epoxy grafting modified waterborne polyurethane resin: 100 parts of PN-110 and 30 parts of solvent acetone were placed in a reactor, stirred and heated to 50°C, and then 50 parts of diphenylmethane diisocyanate and 0.01 parts of stannous octoate were added, and the reaction was carried out until the NCO content was 4.67%, then 7.5 parts of 2,2-dimethylol propionic acid was added and the reaction was carried out until the NCO content was 2.02%, then 6.67 parts of end-capping agent epoxy propanol was added and the reaction was carried out until the NCO infrared peak disappeared, and 5.66 parts of triethylamine was added to neutralize the salt.

[0035] Preparation method of two-component epoxy grafting modified waterborne polyurethane primer: S1. The epoxy grafting modified waterborne polyurethane resin is placed in a high-speed stirring disperser, deionized water is added for emulsification and dispersion, and then distillation under reduced pressure to obtain an epoxy grafting modified waterborne polyurethane emulsion. The above emulsion, carbon black and dispersant are added to a sand mill, and ground until the appearance is uniform and delicate to obtain a two-component epoxy grafting modified waterborne polyurethane primer A component; S2. The hydrophilic polyol and solvent acetone are placed in a reactor, stirred and heated to 50℃, and then triisocyanate and organic tin catalyst stannous octoate are added. After reaction at 50℃ until the NCO content is 5.58%, the temperature is lowered to room temperature. The acetone-dissolved prepolymer is added dropwise to the fatty polyamine solution, and after the dropwise addition is completed, the reaction is continued until the NCO infrared peak disappears. The solvent acetone is removed by distillation under reduced pressure; S3. The modified polyurethane curing agent is added to a stirring disperser, and then amino silane coupling agent and curing accelerator resorcinol are added and stirred uniformly to obtain a two-component epoxy grafting modified waterborne polyurethane primer B component; S4. Before construction, the A component and the B component are mixed uniformly at a mass ratio of 10:1 to obtain a two-component epoxy grafting modified waterborne polyurethane primer.

[0036] The present embodiment provides a series of two-component epoxy grafting modified waterborne polyurethane primers. The weight fractions of the components in the formula are as shown in Tables 1 and 2.

[0037] Table 1 Formula of Examples 1-7

[0038] Table 2 Formula of Examples 8-12

[0039] The weight fractions of the components in the formula of the comparative examples of the present application are as shown in Table 3.

[0040] Table 3 Formula of Comparative Examples 1-10

[0041] 2. Test index (1) Peeling adhesion: tested according to “DVS 1618-2002 Elastic Thick Film Adhesion in Rolling Stock”; The specific implementation steps are as follows: first, the surface of the substrate is thoroughly cleaned with a cleaning agent, and after drying, a layer of primer is uniformly applied to the surface of the substrate with a brush, and after the primer is completely dry, 5 polyurethane adhesive strips with a width of about 10 mm and a length of at least 50 mm are sprayed on the surface of the substrate coated with the primer. The substrate with the sprayed adhesive strips is placed in a standard state (23℃ / 50%RH) for 7 days; after 7 days of curing, the adhesive strips are cut to the adhesive surface with a knife, and the adhesive strips are peeled off with tweezers (peeling angle 130~160°). During the peeling process, the adhesive strips are cut to the adhesive surface every 5~10 mm horizontally, and the cutting section interval time is about 3s. Continue to apply load to the material, and the test length is at least 50 mm. The test sample is a non-self-adhesive two-component polyurethane adhesive with a shear strength of about 5.0MPa; (2) Aging resistance: tested according to "HG / T 4363-2012 Single-component polyurethane adhesive for automobile window glass"; (3) Low temperature adhesion: according to the test method of peel adhesion, the sample was placed in an environment of 0℃ for 6h, and the peel adhesion was observed.

[0042] 3. Test results Table 4 Test results of examples 1~7

[0043] Table 5 Test results of examples 8~12

[0044] Table 6 Test results of comparative examples 1~10

[0045] From the data in Table 4 and Table 5, the series of two-component epoxy grafted modified waterborne polyurethane primers provided in examples 1~12 have excellent adhesion, aging resistance and low temperature adhesion.

[0046] From the data of Table 6, the peel adhesion of the comparative example 1 using a fatty polyamine as the curing agent - diethylenetriamine, and the aluminum material and the plastic significantly decreased, the aging resistance test decreased, and the wet heat resistance decreased, indicating that the modified polyurethane curing agent of the present application improves its adhesion effect and aging resistance; the comparative example 2 used an aromatic polyamine - p-phenylenediamine instead of diethylenetriamine to modify the polyurethane, and the aging resistance and low temperature adhesion decreased; the comparative example 3 used a commercially available polyurethane curing agent, although the peel adhesion was good, the aging resistance test was poor, and the low temperature adhesion was poor; the comparative example 4 used a common silane coupling agent instead of the amino silane coupling agent, and the aging resistance decreased; the comparative example 5 used too little amino silane coupling agent and the comparative example 6 used too much amino silane coupling agent, both of which would cause the aging resistance to decrease; the comparative example 7 had too much fatty amine content in the modified polyurethane curing agent and the comparative example 8 had too little fatty amine content, both of which would cause the aging resistance to decrease, and too little fatty amine content would also decrease the peel adhesion and the low temperature adhesion; the comparative example 9 had too little isocyanate content in the modified polyurethane curing agent, which would decrease the peel adhesion, the aging resistance, and the low temperature adhesion; and the comparative example 10 had too much isocyanate content in the modified polyurethane curing agent, which would cause the wet heat resistance, the water resistance, and the weather resistance to decrease.

[0047] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present application and are not intended to limit the scope of protection of the present application. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present application.

Claims

1. A two-component epoxy graft modified waterborne polyurethane primer, characterized in that: The composition includes the following parts by weight: Component A: 20-30 parts of epoxy graft modified waterborne polyurethane resin, 0.2-0.5 parts of dispersant, 5-8 parts of carbon black, and 67.5-78.8 parts of deionized water; Component B: 80-90 parts of modified polyurethane curing agent, 4-18 parts of aminosilane coupling agent, and 5-10 parts of curing accelerator; The modified polyurethane curing agent is prepared by prepolymerizing a hydrophilic polyol and an isocyanate and chain-extending an aliphatic polyamine. The modified polyurethane curing agent does not contain an NCO group and has a number average molecular weight of 1,000 to 10,000. In the modified polyurethane curing agent, the ratio of the total molar amount of hydroxyl groups of the hydrophilic polyol, the total molar amount of cyanate groups of the isocyanate, and the molar amount of the fatty polyamine is 1:3-3.5:2-2.5; The total molar amount of the cyanate groups of the isocyanate is equal to the sum of the total molar amount of the hydroxyl groups of the hydrophilic polyol and the molar amount of the fatty polyamine; The isocyanate is at least one of diisocyanate or triisocyanate.

2. The two-component epoxy graft modified waterborne polyurethane primer according to claim 1, characterized in that: The weight proportion of the aminosilane coupling agent is 5-15 parts.

3. The two-component epoxy graft modified waterborne polyurethane primer according to claim 1, characterized in that: The isocyanate is diphenylmethane diisocyanate, toluene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, and the triisocyanate is at least one of HDI trimer, TDI trimer, IPDI trimer and HDI biuret.

4. The two-component epoxy graft modified waterborne polyurethane primer according to claim 1, characterized in that: The mass ratio of component A to component B is in the range of 5 to 10:

1.

5. The two-component epoxy graft modified waterborne polyurethane primer according to claim 1, characterized in that: The aminosilane coupling agent is at least one of 3-aminopropyltriethoxysilane, N-2-aminoethyl-3-aminopropyltrimethoxysilane, 3-diethylenetriaminopropyltrimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane or bis(3-trimethoxysilylpropyl)amine.

6. The two-component epoxy graft modified waterborne polyurethane primer according to claim 1, characterized in that: The fatty polyamine is at least one of ethylenediamine, hexamethylenediamine, diethylenetriamine or triethylenetetramine.

7. The two-component epoxy graft modified waterborne polyurethane primer according to claim 1, characterized in that: The epoxy graft modified waterborne polyurethane resin is obtained by prepolymerizing polyester polyol and diisocyanate, and then adding glycidol and a neutralizer after hydrophilic chain extension.

8. The method for preparing the two-component epoxy graft modified waterborne polyurethane primer according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1. The epoxy graft modified waterborne polyurethane resin emulsion, carbon black, and dispersant are mixed to obtain component A; S2. Heat the hydrophilic polyol and solvent to 50 ± 2°C, add isocyanate and organotin catalyst, and add the fatty polyamine solution to react to obtain a modified polyurethane curing agent; S3. Add the modified polyurethane curing agent prepared in step S2 into a stirring disperser, add an aminosilane coupling agent and a curing accelerator, and obtain a two-component epoxy graft modified waterborne polyurethane primer component B.

9. Use of the two-component epoxy graft modified waterborne polyurethane primer according to any one of claims 1 to 7 in automobile glass installation.

10. The use according to claim 9, characterized in that The components A and B were mixed uniformly at a mass ratio of 10:1.

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