Low-odor hydrolysis-resistant thiol curing agent as well as preparation method and application thereof

Abstract

The invention belongs to the field of new materials, and provides a low-odor hydrolysis-resistant thiol curing agent and a preparation method and application thereof, and the low-odor hydrolysis-resistant thiol curing agent is obtained by reaction of polyether polyol, halogenated hydrocarbon and a sulfhydrylation reagent; wherein the mass content of carbonyl in the polyether polyol is less than 100 ppm, and the mercaptan curing agent finally obtained by controlling the carbonyl content in the polyether polyol has the characteristics of low odor and hydrolysis resistance. The thiol curing agent can be independently used or mixed with other thiol compounds, and the thiol curing agent and epoxy resin are cured under the action of an accelerant and an auxiliary agent to prepare an epoxy adhesive. The adhesive has extremely low odor, can ensure the health of a user, can still keep stable bonding strength and other properties after being used outdoors for a long time, and is widely applied to outdoor repair and other operations.

Description

Technical Field

[0001] The invention belongs to the field of new materials, and in particular relates to epoxy adhesives. It provides a low-odor, hydrolysis-resistant thiol curing agent, a preparation method and an application thereof. Background Art

[0002] Epoxy resin adhesives are widely used for general and special purposes such as leak prevention, sealing, bonding, coatings and surface construction due to their excellent properties such as high bonding strength, easy operation, chemical resistance and aging resistance. Common curing agents for epoxy resins are mainly thiols, amines, anhydrides, imidazoles, etc. Traditional epoxy curing agents require 24 hours to completely gel at room temperature, but when thiol curing agents are present, they can be cured quickly in 5 minutes, so they are widely used in quick repair adhesives and winter operations.

[0003] However, thiol curing agents emit odor during use, which will directly affect the health of users. At the same time, when used outdoors for a long time, they are very likely to cause the colloid to crack after being eroded by the environment, thus reducing the service life of the epoxy adhesive.

[0004] Therefore, how to find a curing agent that will not have a negative impact on the environment and human health, will not affect other properties of the thiol curing agent, and is more suitable for outdoor use environments is a problem that needs to be solved urgently in this field. Summary of the invention

[0005] In view of the problems existing in the prior art, the present invention provides a preparation method and application of a low-odor, hydrolysis-resistant thiol curing agent, the preparation method comprising a reaction step of a polyether polyol, a halogenated hydrocarbon and a thiolating agent; wherein the mass content of carbonyl in the polyether polyol is less than 100ppm, and the thiol curing agent finally obtained by controlling the carbonyl content in the polyether polyol has the characteristics of low odor and hydrolysis resistance. The thiol curing agent can be cured alone or mixed with other thiol compounds with epoxy resin under the action of a promoter and an auxiliary agent to prepare an epoxy adhesive; the adhesive has an extremely low odor, can ensure the health of the user, and can still maintain stable bonding strength and other properties after long-term outdoor use, and is widely used in outdoor repair and other operations.

[0006] The specific technical solutions of the present invention are as follows: The inventors firstly provide a low-odor and hydrolysis-resistant mercaptan curing agent, which is obtained by reacting polyether polyol, halogenated hydrocarbon and thiol-forming agent, and the characteristic of the curing agent is that the carbonyl mass content of the polyether polyol is less than 100 ppm.

[0007] Furthermore, the halogenated hydrocarbon is epichlorohydrin; and the thiol-forming agent is selected from one of sodium sulfide, sodium hydrosulfide, thiourea and sodium polysulfide.

[0008] Compared with the prior art, the biggest feature of the present application is to control the mass content of carbonyl groups in the polyether polyol to be less than 100ppm; when the mass content of carbonyl groups in the polyether polyol is ≥100ppm, the odor of the adhesive will become larger and the water resistance will deteriorate, affecting its bonding strength. The inventor selects qualified raw materials by testing the carbonyl content of the purchased polyether polyols. The specifically selected polyether polyol has a hydroxyl value of 200-700KOH / g, and more specifically can be selected from Yantai Wanhua Chemical R2302, Bluestar Dongda MN-500, Nantong Chenrun GP-303, Yinuowei New Materials C303, Shandong Longhua New Materials C304, Zibo Dexin Federal DMN-450. The carbonyl content must be tested before use, and it can be used in the technical solution of the present application only if it meets the above standards.

[0009] Furthermore, the inventors provide a method for preparing the above-mentioned low-odor hydrolysis-resistant thiol curing agent, the specific steps are as follows: (1) Add a polyether polyol having a carbonyl mass content of less than 100 ppm and a catalyst into a reaction vessel, then slowly drop a halogenated hydrocarbon therein, control the dropping temperature and the dropping time, then sequentially add a thiolating agent and a phase transfer catalyst, fill with protective gas, and keep the reaction at a certain temperature; (2) After the reaction is completed, the aqueous phase is removed, a certain amount of water is added to the organic phase, and then dilute sulfuric acid is added to adjust the pH to 3-5, and the mixture is stirred for 5 hours. The mixture is allowed to stand for separation, and then a certain amount of water is added to the organic phase, and the mixture is washed with water for 5 hours. The mixture is separated, and the thiol curing agent is obtained by rotary evaporation.

[0010] Preferably, the molar ratio of the halogenated hydrocarbon to the polyether polyol is (0.5-6):1, and the halogenated hydrocarbon is epichlorohydrin.

[0011] The catalyst is selected from one of tin tetrachloride, stannous octoate, tributyltin chloride, boron trifluoride, and boron trifluoride ethyl ether; the amount of the catalyst is 0.05-6% of the mass of the polyether polyol, the dropping temperature of the polyether polyol and the halogenated hydrocarbon is 28-75°C; the dropping reaction time is 3-11h. The above reaction parameters can ensure that the first step intermediate of the synthesis meets the requirements, the viscosity is 2000-3000mpa.s, and the residual amount of the halogenated hydrocarbon is 0.

[0012] The thiolating agent is selected from one of sodium sulfide, sodium hydrosulfide, thiourea and sodium polysulfide, the molar ratio of the thiolating agent to the halogenated hydrocarbon is (1-9):1, the reaction temperature is 70-130°C, the reaction time is 3-10h, and the reaction pressure is 0.1-10MPa.

[0013] The protective gas is selected from one of carbon dioxide, nitrogen, hydrogen sulfide and argon.

[0014] The phase transfer catalyst is selected from tetrabutylammonium chloride, tetrabutylammonium bromide, polyethylene glycol, and glycerol; the amount of the phase transfer catalyst is 0.5-25% of the mass of the polyether polyol. The water washing time in the above step (2) can also be based on the content of the above phase transfer catalyst, and the water washing can be carried out until the residual phase transfer catalyst content in the system is less than 0.5%.

[0015] Furthermore, in the preparation method of the thiol curing agent, the amount of the catalyst is 0.3-5% of the mass of the polyether polyol, the reaction temperature of the polyether polyol and the halogenated hydrocarbon is 35-70°C, and the reaction time is 3-9h; the thiolating agent is selected from one of sodium hydrosulfide, sodium polysulfide, and thiourea; the molar ratio of the thiolating agent to the halogenated hydrocarbon is (2-6):1, the reaction temperature of the thiolating reaction is 80-120°C, the reaction pressure is 0.1-6MPa, and the reaction time is 3-7h; the protective gas is nitrogen or hydrogen sulfide, and the phase transfer catalyst is selected from tetrabutylammonium bromide or polyethylene glycol, and the amount is 5-10% of the mass of the polyether polyol.

[0016] The chromaticity of the mercaptan curing agent obtained above is less than or equal to 15, the viscosity is 12000-14000 mpa.s, the mercapto content is greater than or equal to 12%, the low boiling point content is less than or equal to 1.2%, and the total chlorine content is less than or equal to 800 ppm.

[0017] After obtaining the above-mentioned thiol curing agent, the present invention further provides an epoxy adhesive composition, which comprises, by weight, 10-90 parts of the above-mentioned thiol curing agent, 10-90 parts of epoxy resin, and 0.1-15 parts of accelerator.

[0018] Preferably, the contents of the components in the composition are as follows, by weight: 30-60 parts of thiol curing agent, 30-60 parts of epoxy resin, and 2-9 parts of accelerator.

[0019] Among them, the epoxy resin is selected from one or two of glycidyl ether epoxy resins, glycidyl ester epoxy resins, glycidyl amine epoxy resins, alicyclic epoxy resins, epoxidized olefin epoxy resins, hydantoin epoxy resins, imide epoxy resins, silicone epoxy resins, and organic iron epoxy resins; preferably, it is a combination of one or two of glycidyl ether epoxy resins and glycidyl ester epoxy resins.

[0020] The accelerator is selected from ethylenediamine, 1,2-diaminopropane, 1,3-diaminopropane, 1,5-diaminopentane, hexamethylenediamine, tetramethylenediamine, trimethylhexamethylenediamine, 2-methyl-1,5-diaminopentane, polyetherdiamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, diethylenepropylamine, polyamide, isophoronediamine, N-aminoethylpiperazine, meta-phenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, meta-phenylenediamine, dicyandiamide, adipic acid dihydrazide, dipropylenetriamine, bis(hexamethylene)triamine, 2,4,6-tris(dimethylamino)methyl One or more of tris(2-ethylhexanoic acid), 2,4,6-tris(dimethylaminomethylphenol) tris(2-ethylhexanoic acid) salt, 2,4,6-tris(dimethylaminomethylphenol) trioleate, benzyldimethylamine, ethylenediamine, triethanolamine, o-hydroxybenzyldimethylamine, acetylacetone metal salt, triphenylphosphine and its phosphonium salt, active tris(2-ethylhexanoic acid) chromium, organic acid salt amine complex, 1,8-diaza-bicyclo(5,4,0)-7-undecene, 2-thiolbenzothiazole, thiourea and its derivatives, cycloalkylimidazoline, 2-imidazoline, aromatic tertiary amine containing epoxy group, phthalate accelerator; More preferably, it is one of 2,4,6-tris(dimethylaminomethylphenol), benzyldimethylamine, ethylenediamine, triethanolamine, o-hydroxybenzyldimethylamine, triphenylphosphine, diethylenetriamine, triethylenetetramine and tetraethylenepentamine.

[0021] In summary, the present invention provides a method for preparing a low-odor, hydrolysis-resistant thiol curing agent, and further provides an epoxy adhesive composition. The adhesive has extremely low odor, which greatly reduces the impact on people's physical and mental health during use. At the same time, it can still maintain stable bonding strength and other properties after long-term outdoor use. It can be widely used in outdoor repair operations and has very good application prospects. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] The detection methods in the following embodiments are exemplified as follows: 1. Detection method of carbonyl content Based on the principle of producing hydrazone derivatives by the reaction of carbonyl compounds with 2,4-dinitrophenylhydrazine, the carbonyl group in polyether polyols was tested by spectrophotometry.

[0024] 2. Test method for odor level of mercaptan curing agents 200 g of thiol curing agent was placed in a 250 mL polytetrafluoroethylene bottle and the bottle cap was tightly closed. It was then placed in an oven at 80°C for 24 hours. Seven people smelled and scored the odor respectively, and the average value was taken as the product odor.

[0025] Odor rating: 1-no odor; 2-slight odor; 3-smell; non-irritating; 4-irritating odor; 5-strong irritating odor.

[0026] 3. Water absorption test Mix the mercaptan curing agent with the epoxy resin and the accelerator and place them for 24 hours to form a solidified product. The mass of the solidified product is weighed and recorded as W. 1 Then put the solidified product in a beaker filled with distilled water and place it at 30℃ for 7 days. Then take out the sample, absorb the water on the surface of the sample with absorbent paper, and then measure its mass as W. 2 , and then calculate the water absorption rate: Water absorption rate = (W 2 -W 1 )*100% / W 1 。

[0027] 4. Tensile strength test The tensile strength of the adhesive is tested using the national standard GB / T1040.2-2022.

[0028] 5. Outdoor debonding test The cured epoxy adhesive made of mercaptan curing agent, epoxy resin and accelerator was placed outdoors for 6 months, and then the surface condition of the cured product was observed.

[0029] Example 1 A thiol curing agent and a preparation method thereof, the specific steps are as follows: (1) Add 150g of polyether polyol (R2302 from Yantai Wanhua Chemical, with a carbonyl content of 50ppm) and 0.74g of catalyst SnCl into the reaction vessel. 4 •5H 2 O, slowly add 177g of epichlorohydrin (99.5%), the dropping temperature is 60°C, and the dropping time is 5h; then add 292g of NaHS solution (44wt%) and 14g of tetrabutylammonium chloride in sequence, and fill with protective gas H 2 S (pressure 0.5Mpa), keep the reaction at 100℃ for 5h.

[0030] (2) After the reaction is completed, the aqueous phase is removed, 600 g of water is added to the organic phase, and then dilute sulfuric acid is added to adjust the pH to 3-5, and the mixture is stirred for 5 hours. The mixture is allowed to stand for separation, and then 600 g of water is added to the organic phase. The mixture is washed with water for 5 hours, separated, and 275.00 g of a thiol curing agent is obtained by rotary evaporation.

[0031] The odor standard for testing and evaluating products is 1.

[0032] Example 2 A thiol curing agent and a preparation method thereof, the specific steps are as follows: (1) Add 150g of polyether polyol (Bluestar Dongda MN-500, with a carbonyl content of 30ppm) and 1.15g of catalyst stannous octoate into the reaction vessel, slowly drop 144g of epichlorohydrin (99.5%) into the bottle at a temperature of 50°C for about 6h, then add 256g of NaHS solution (32wt%) and 16g of glycerol in turn, and fill with protective gas N 2 (pressure 0.6Mpa), keep the reaction at 90℃ for 7h.

[0033] (2) After the reaction is completed, the aqueous phase is removed, 600 g of water is added to the organic phase, and then dilute sulfuric acid is added to adjust the pH to 3-5, and the mixture is stirred for 5 hours. The mixture is allowed to stand for separation, and then 600 g of water is added to the organic phase, and the mixture is washed with water for 5 hours. The mixture is separated, and 274.00 g of a thiol curing agent is obtained by rotary evaporation.

[0034] The odor standard for testing and evaluating products is 1.

[0035] Example 3 A thiol curing agent and a preparation method thereof, the specific steps are as follows: (1) Add 150g of polyether polyol (DMN-450 from Zibo Dexin Federal, with a carbonyl content of 100ppm) and 1.48g of tributyltin chloride as a catalyst to a reaction vessel, slowly drop 165g of epichlorohydrin (99.5%) into the bottle at a temperature of 50°C for 7h, then add 361g of NaHS solution (33wt%) and 25g of tetrabutylammonium bromide in sequence, and fill with protective gas H 2 S (pressure 0.3Mpa), and react at 110℃ for 3h.

[0036] (2) After the reaction is completed, the aqueous phase is removed, 600 g of water is added to the organic phase, and then dilute sulfuric acid is added to adjust the pH to 3-5, and the mixture is stirred for 5 hours. The mixture is allowed to stand for separation, and then 600 g of water is added to the organic phase, and the mixture is washed with water for 5 hours. The mixture is separated, and 276.00 g of a thiol curing agent is obtained by rotary evaporation.

[0037] The odor standard for the product tested and evaluated is 2.

[0038] Example 4 A thiol curing agent and a preparation method thereof, the specific steps are as follows: (1) Add 150g of polyether polyol (C303 from Innovative Materials, with a carbonyl content of 10ppm) and 0.58g of catalyst SnCl into the reaction vessel. 4 ·5H 2O, slowly add 159g of epichlorohydrin (99.5%) to the bottle, the dropping temperature is 55℃, the dropping time is about 5h, after the dropping is completed, the temperature is raised to 60℃ and kept warm for 2h, 358.27g of NaHS solution (32wt%) and 13.7g of tetrabutylammonium bromide are added in sequence, and the protective gas CO is filled in. 2 (pressure 0.6Mpa), keep the reaction at 120℃ for 3h.

[0039] (2) After the reaction is completed, the aqueous phase is removed, 600 g of water is added to the organic phase, and then dilute sulfuric acid is added to adjust the pH to 3-5, and the mixture is stirred for 5 hours. The mixture is allowed to stand for separation, and then 600 g of water is added to the organic phase, and the mixture is washed with water for 5 hours. The mixture is separated, and 269.00 g of a thiol curing agent is obtained by rotary evaporation.

[0040] The odor standard for testing and evaluating products is 1.

[0041] Example 5 A thiol curing agent and a preparation method thereof, the specific steps are as follows: (1) Add 150g of polyether polyol (Nantong Chenrun GP-303, carbonyl content 10ppm) and 0.80g of catalyst SnCl into the reaction vessel. 4 ·5H 2 O, slowly add 148g of epichlorohydrin (99.5%) to the bottle, the dropping temperature is 60℃, the dropping time is about 9h, after the dropping is completed, the temperature is raised to 65℃ and kept warm for 1h, 358.27g of NaHS solution (32wt%) and 13.7g of tetrabutylammonium bromide are added in sequence, and the protective gas H is filled in. 2 S (pressure 0.5 MPa), and react at 120°C for 5 h.

[0042] (2) After the reaction is completed, the aqueous phase is removed, 600 g of water is added to the organic phase, and then dilute sulfuric acid is added to adjust the pH to 3-5, and the mixture is stirred for 5 hours. The mixture is allowed to stand for separation, and then 600 g of water is added to the organic phase, and the mixture is washed with water for 5 hours. The mixture is separated, and 269.00 g of a thiol curing agent is obtained by rotary evaporation.

[0043] The odor standard for testing and evaluating products is 1.

[0044] Comparative Example 1 Compared with Example 5, except for the use of different polyether polyols (NJ-303E from a company in Jiangsu, the carbonyl content was 500ppm after one year of storage), other conditions were the same as those in Example 5, and 269.09g of thiol curing agent was obtained.

[0045] The odor standard of the product tested and evaluated is 5.

[0046] Comparative Example 2 Compared with Example 5, except for the use of polyether polyol (NJ-303E from a company in Jiangsu, the carbonyl content of which was 200 ppm after being stored for half a year), other conditions were the same as those of Example 5, and 267.59 g of thiol curing agent was obtained.

[0047] The odor standard of the product tested and evaluated is 4.

[0048] Comparative Example 3 Compared with Example 5, except for the polyether polyol (NJ-303E from a company in Jiangsu, the carbonyl content was 300 ppm after being stored for eight months), other conditions were the same as those in Example 5, and 267.12 g of thiol curing agent was obtained.

[0049] The odor standard of the product tested and evaluated is 4.

[0050] Comparative Example 4 Compared with Example 5, except for the polyether polyol (HF-204 from a Zhejiang company, the carbonyl content of which was 400 ppm after being stored for one year), other conditions were the same as those of Example 5, and 266.10 g of thiol curing agent was obtained.

[0051] The odor standard of the product tested and evaluated is 5.

[0052] Comparative Example 5 Compared with Example 5, except for the use of polyether polyol (HF-204 from a Zhejiang company, with a carbonyl content of 130 ppm), other conditions are the same as those of Example 5, and 266.10 g of thiol curing agent is obtained.

[0053] The odor standard of the product tested and evaluated is 5.

[0054] Application Example 1 At 25°C and 50% RH, 50 g of liquid thiol curing material (the product prepared in Example 1) and 2.5 g of 2,4,6-tris(dimethylaminomethylphenol) were mixed, and then 50 g of epoxy resin E51 was added. The mixture was pre-mixed for 20 seconds using a spatula, and then degassed to obtain an epoxy adhesive having a diameter of about 8 cm and a thickness of 0.8 cm. The water absorption and tensile strength thereof were then tested.

[0055] Application Examples 2-5 With other conditions unchanged, the mercaptan curing material in Example 1 was replaced by the products in Examples 2-5, respectively, and the water absorption and tensile strength of the epoxy adhesives were tested after preparation.

[0056] Application Comparative Examples 1-5 With other conditions unchanged, the thiol solidified product in Example 1-4 was replaced by the product in Comparative Example 1-5, and the water absorption and tensile strength of the solidified product were tested after preparation.

[0057] Application Examples 6-9 According to the operating scheme of Application Example 5, the epoxy resins are replaced in the order of the application examples as follows: epoxy resin E44, epoxy resin E42, epoxy resin E55, and epoxy resin E51; the accelerators are replaced in the order of the application examples as follows: benzyldimethylamine, triethanolamine, diethylenetriamine, and triethylenetetramine, and the epoxy adhesives are prepared and then tested for water absorption and tensile strength, and the surface state of the cured product is observed after being placed outdoors for 6 months.

[0058] The performance test results of the final products of each application example and application comparison example are shown in Table 1: Table 1 It can be found from the table that the effects of application examples 4-9 are significantly better than those of application examples 1-3, but the effects of application examples 1-3 are significantly better than those of application comparative examples 1-5. This indicates that by controlling the mass content of carbonyl groups in the raw material polyether polyol, a thiol curing agent with low odor can be obtained, and the obtained epoxy adhesive has low water absorption, and the tensile strength does not change significantly. At the same time, after long-term outdoor use, it can still maintain stable bonding strength and other properties, and can be widely used in outdoor repair operations, while the curing agent of application comparative examples 1-5 does not have the above characteristics.

[0059] The above embodiments enable those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A low-odor, hydrolysis-resistant thiol curing agent obtained by reacting a polyether polyol, a halogenated hydrocarbon and a thiol-forming agent, characterized in that: The carbonyl mass content of the polyether polyol is less than 100 ppm.

2. The low-odor, hydrolysis-resistant mercaptan curing agent according to claim 1, characterized in that: The halogenated hydrocarbon is epichlorohydrin; the thiol-forming agent is selected from one of sodium sulfide, sodium hydrosulfide, thiourea and sodium polysulfide.

3. An epoxy adhesive composition containing the thiol curing agent according to claim 1, characterized in that: The composition thereof is calculated by weight as follows: 10-90 parts of mercaptan curing agent, 10-90 parts of epoxy resin, and 0.1-15 parts of accelerator.

4. The epoxy adhesive composition according to claim 3, characterized in that: The composition thereof is calculated by weight as follows: 30-60 parts of mercaptan curing agent, 30-60 parts of epoxy resin, and 2-9 parts of accelerator.

5. The epoxy adhesive composition according to claim 3 or 4, characterized in that: The epoxy resin is selected from one or two of glycidyl ether epoxy resin, glycidyl ester epoxy resin, glycidyl amine epoxy resin, alicyclic epoxy resin, epoxidized olefin epoxy resin, hydantoin epoxy resin, imide epoxy resin, silicone epoxy resin and organoferric epoxy resin.

6. The epoxy adhesive composition according to claim 3 or 4, characterized in that: The accelerator is selected from ethylenediamine, 1,2-diaminopropane, 1,3-diaminopropane, 1,5-diaminopentane, hexamethylenediamine, tetramethylenediamine, trimethylhexamethylenediamine, 2-methyl-1,5-diaminopentane, polyetherdiamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, diethylenepropylamine, polyamide, isophoronediamine, N-aminoethylpiperazine, meta-phenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, meta-phenylenediamine, dicyandiamide, adipic acid dihydrazide, dipropylenetriamine, bis(hexamethylene)triamine, 2,4,6-tri(dimethylamino) methylphenol), 2,4,6-tris(dimethylaminomethylphenol) tris(2-ethylhexanoic acid) salt, 2,4,6-tris(dimethylaminomethylphenol) trioleate, benzyldimethylamine, ethylenediamine, triethanolamine, o-hydroxybenzyldimethylamine, acetylacetone metal salt, triphenylphosphine and its phosphonium salt, active tris(2-ethylhexanoic acid) chromium, organic acid salt amine complex, 1,8-diaza-bicyclo(5,4,0)-7-undecene, 2-thiolbenzothiazole, thiourea and its derivatives, cycloalkylimidazoline, 2-imidazoline, aromatic tertiary amine containing epoxy group, one of phthalate accelerators.

7. The epoxy adhesive composition according to claim 5, characterized in that: The epoxy resin is selected from one or a combination of glycidyl ether epoxy resin and glycidyl ester epoxy resin.

8. The epoxy adhesive composition according to claim 6, characterized in that: The accelerator is selected from one of 2,4,6-tris(dimethylaminomethylphenol), benzyldimethylamine, ethylenediamine, triethanolamine, o-hydroxybenzyldimethylamine, triphenylphosphine, diethylenetriamine, triethylenetetramine and tetraethylenepentamine.

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