A fast-curing thermally conductive and flame-retardant epoxy adhesive and its preparation method

Abstract

This application discloses a fast-curing, thermally conductive, and flame-retardant epoxy adhesive. The raw materials for preparation include component A and component B. Component A, by weight, comprises: 14-25 parts epoxy resin, 5-20 parts modified epoxy resin, 3-8 parts toughening agent I, 3-6 parts diluent, 0.5-2.5 parts coupling agent I, 0-1 part additives, 0.3-1.5 parts thixotropic agent I, and 55-70 parts thermally conductive and flame-retardant filler I. Component B is the curing component. This invention is applied to the fixing of battery cells to the bottom water-cooling plate, suitable for power battery PACK modules. It exhibits good adhesion to untreated PI and PET films, excellent aging performance, stable storage period, resistance to high and low temperature shocks, high thermal conductivity, and achieves V0 flame-retardant performance. Furthermore, its fast-curing properties well meet the requirements of early-stage production processes.

Description

TECHNICAL FIELD

[0001] The application relates to a rapid-curing heat-conducting flame-retardant epoxy adhesive and a preparation method thereof, and relates to the field of adhesives. BACKGROUND

[0002] With the continuous development of new energy technology, new energy vehicles have higher and higher requirements for the energy density and battery capacity of power batteries. While the performance of power batteries is continuously improved, the heat problem is becoming more and more serious. Long-term high temperature will adversely affect the performance of the battery. Equipping the power battery with a water-cooling system is an important means to improve the heat problem of the battery. The adhesive for fixing the battery module and the cooling system needs to have firm bonding effect, good heat conduction and flame-retardant performance, and in order to prolong the service life of the battery, the adhesive also needs to have good aging resistance and be suitable for application in a high-temperature and high-humidity environment. The surface material of the battery module is mainly aluminum alloy, PI film and PET film. The existing epoxy curing structural adhesive needs 7 days to reach the final strength, the storage stability period of the adhesive is less than 15 days, the controllability of the adhesive is poor, and it is difficult to meet the production rhythm. Moreover, the heat-conducting epoxy resin adhesive has poor bonding effect on untreated PI and PET films, which increases the complexity of the production steps.

[0003] Chinese patent CN202210142320.5 discloses a two-component polyurethane adhesive for power battery structure bonding and a preparation method thereof. By adding a polyol containing a benzene ring, the mechanical strength, high-temperature resistance of the structural adhesive is increased, the bonding strength to metal, PET film and electrophoretic plate is enhanced, and the hydrolysis resistance of the structural adhesive is improved, so that the structural adhesive has low modulus, good electrical insulation, high flame retardance and excellent high-temperature and high-humidity resistance. However, the heat conduction performance is poor, and the heat exchange efficiency between the battery system and the cooling system is low. Chinese patent CN202110030642.6 discloses a high-humidity-resistant and heat-resistant heat-conducting structural adhesive for power battery bonding, preparation and use. By matching a specific complex amine crosslinking agent with a flexible modified epoxy resin, a micro-phase separation two-phase network structure is formed in the high-molecular network structure, which helps to reduce the hardness and elastic modulus of the cured product while improving the wet-heat post-tensile shear strength retention rate. However, the curing speed of the prepared structural adhesive is slow, resulting in a long production and processing time. SUMMARY

[0004] In order to prepare an epoxy adhesive which can be rapidly cured at room temperature, has excellent adhesive force, excellent aging performance, stable storage period, high-temperature and low-temperature impact resistance, high thermal conductivity and V0 flame retardant performance, the first aspect of the present application provides a rapidly cured thermal conductive flame-retardant epoxy adhesive, the preparation raw materials of the A component and the B component, the preparation raw materials of the A component include: epoxy resin 14-25 parts, modified epoxy resin 5-20 parts, toughening agent I 3-8 parts, diluent 3-6 parts, coupling agent I 0.5-2.5 parts, auxiliary agent 0-1 part, thixotropic agent I 0.3-1.5 parts, thermal conductive flame-retardant filler I 55-70 parts by weight; the B component is a curing component.

[0005] As a preferred embodiment, the preparation raw materials of the B component include: curing agent 20-35 parts, accelerator 0-1 part, toughening agent II 0.5-5 parts, coupling agent II 0.5-2.5 parts, thixotropic agent II 0.3-1 part, thermal conductive flame-retardant filler II 55-70 parts by weight.

[0006] As a preferred embodiment, the epoxy resin is bisphenol A epoxy resin, the epoxy equivalent weight of the bisphenol A epoxy resin is 184-195 g / mol, and the viscosity at 25 DEG C is 12000-15000 mPa s.

[0007] As a preferred embodiment, the bisphenol A epoxy resin is selected from one or a combination of 618 epoxy resin, 616 epoxy resin and 6101 epoxy resin.

[0008] As a preferred embodiment, the modified epoxy resin is polyurethane modified epoxy resin, the epoxy equivalent weight of the polyurethane modified epoxy resin is 210-630 g / mol, and the viscosity at 25 DEG C is 20000-70000 mPa s.

[0009] As a preferred embodiment, the polyurethane modified epoxy resin is selected from one or a combination of EPU-133L, EPU-302 and EPU-300S.

[0010] The applicant found during the experiment that when the curing speed of the prepared epoxy adhesive is too fast, the brittleness of the adhesive is high, which leads to the decline of the bonding performance between the adhesive and the bonding substrate. The applicant found that by introducing a polyurethane modified epoxy resin with an epoxy equivalent weight of 210-250 g / mol and a viscosity of 40,000-60,000 mPa·s, and the weight ratio of the epoxy resin to the polyurethane modified epoxy resin is (14-25):(5-20), the toughness of the adhesive is improved, and the bonding effect of the obtained adhesive is best. The possible reason is that when the epoxy equivalent weight is 210-250 g / mol, the weight ratio of (14-25):(5-20) is used, the epoxy resin and the polyurethane modified epoxy resin can form an interpenetrating network structure, but the compatibility of the polyurethane structure and the epoxy structure is poor, and only under the preferred physical property parameters, forced miscibility can be achieved to increase the compatibility effect, but when the weight ratio exceeds the preferred range, the interpenetrating network structure will collapse, the polyurethane structure and the epoxy structure will separate, cracks will be formed, the shear strength of the adhesive will decrease, and the mechanical properties of the aging resistance will be affected.

[0011] As a preferred embodiment, the toughening agent I and the toughening agent II are selected from one or a combination of QB9466, MX-154, PB-1300, and CTBN modifier.

[0012] As a preferred embodiment, the diluent is selected from one or a combination of dodecyl glycidyl ether, benzyl glycidyl ether, phenyl glycidyl ether, ethylene glycol diglycidyl ether, butanediol diglycidyl ether, and polyhydroxy polyether.

[0013] As a preferred embodiment, the curing agent is selected from one or a combination of an amine curing agent or a polythiol curing agent, the amine curing agent is selected from one or a combination of a polyamide curing agent, an alicyclic amine curing agent, and a polyether amine curing agent.

[0014] As a preferred embodiment, the curing agent is a combination of an amine curing agent and a polythiol curing agent, and the weight ratio of the amine curing agent to the polythiol curing agent is (18-23):(9-15).

[0015] As a preferred embodiment, the polythiol curing agent is selected from one or a combination of Japan Toray QE340M, Covestro Capcure3800, GABREL GMP800, and Green Light GL1800.

[0016] The applicants found in the experiment that the use of polythiol curing agent, especially polythiol curing agent with active hydrogen equivalent of 224 g / eq, together with amine curing agent can improve the curing speed of the adhesive, shorten the operable time, maintain the toughness of the adhesive, and avoid the embrittlement problem caused by too fast curing. The possible reason is that polythiol with active hydrogen equivalent of 224 g / eq can form thiolate anion in the system, and the thiolate anion as a very strong nucleophile can quickly open the epoxy group to react, so that the epoxy adhesive can be rapidly cured at room temperature. However, the epoxy structure of the rapidly cured epoxy resin is not easy to deform, and the structure is relatively brittle. By using the weight ratio of amine curing agent to polythiol curing agent of (18-23):(9-15), the epoxy structure can be interpenetrated, the toughness of the cured product can be increased, and the embrittlement problem caused by too fast curing can be avoided.

[0017] As a preferred embodiment, the thermal conductivity of the thermal conductive and flame-retardant filler I and the thermal conductive and flame-retardant filler II is 0.8-3.2 W / m.K, the D50 is 8-25 μm, and the oil absorption is 10-23 g / 100 g.

[0018] As a preferred embodiment, the thermal conductivity of the thermal conductive and flame-retardant filler I is 1.7-2.2 W / m.K, the D50 is 10-18 μm, and the oil absorption is 10-19 g / 100 g.

[0019] As a preferred embodiment, the thermal conductivity of the thermal conductive and flame-retardant filler II is 2.8-3.2 W / m.K, the D50 is 20-25 μm, and the oil absorption is 10-19 g / 100 g.

[0020] As a preferred embodiment, the thermal conductive and flame-retardant filler I and the thermal conductive and flame-retardant filler II are selected from one or a combination of DCS-1000E, DCS-1500E, DCS-2000E, and DCS-3000E, which are purchased from Guangdong Dongguan Dongchao New Material Co., Ltd.

[0021] During the experiment, the applicant discovered that using thermally conductive and flame-retardant fillers with particle sizes of 10-18 μm and 20-25 μm can produce epoxy adhesives with high thermal conductivity. Furthermore, the resulting epoxy adhesive exhibits stable performance and maintains excellent dielectric properties over a long period. The applicant speculates that this is likely because the combined use of 10-18 μm and 20-25 μm fillers results in a high thermal conductivity, leading to better thermal conductivity in the epoxy adhesive. Additionally, the use of fillers with different particle sizes allows for interleaving, reducing voids and further enhancing the thermal conductivity of the epoxy adhesive. When the particle size is below the preferred size, heat transfer resistance increases, and the thermal conductivity of the filler decreases. Conversely, when the particle size is above the preferred size, sedimentation and stratification of the filler can easily occur, affecting the stability of the epoxy adhesive.

[0022] In a preferred embodiment, the coupling agent II is an amino-containing siloxane, which is selected from one or a combination of several of γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, and N-phenylaminomethyltriethoxysilane.

[0023] In a preferred embodiment, the coupling agent I is selected from one or a combination of several of γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, and vinyltriethoxysilane.

[0024] In a preferred embodiment, the additive is selected from one or a combination of several of the following: defoamer, antioxidant, and dispersant.

[0025] In a preferred embodiment, the additive is a dispersant.

[0026] During the experiment, the applicant discovered that using a weight ratio of (55-70):(0-1) for thermally conductive flame-retardant filler and dispersant in component A can improve the stability of epoxy adhesive, avoid sedimentation problems, and exhibit high stability in harsh environments, without yellowing or stratification. The possible reason is that the thermally conductive flame-retardant filler has a high weight ratio. If it exceeds the preferred weight ratio range, the thermally conductive flame-retardant filler will have poor dispersibility in epoxy resin, and is prone to agglomeration, sedimentation, and stratification. By adding a dispersant with a preferred weight ratio, the high molecular weight alkyl ammonium salt copolymer dispersant can increase the molecular resistance between thermally conductive flame-retardant fillers, reduce agglomeration between them, and avoid sedimentation problems, thereby giving it excellent stability during storage.

[0027] A second aspect of the present invention provides a method for preparing a rapid-curing, thermally conductive, and flame-retardant epoxy adhesive, comprising the following steps:

[0028] (1) Add epoxy resin, modified epoxy resin, diluent, and additives to a reaction vessel, control the rotation speed at 1000-1500 r / min, control the temperature at 45-55℃, and stir thoroughly. Then add coupling agent I, toughening agent I, and thermally conductive and flame-retardant filler I, control the rotation speed at 1200 r / min-2500 r / min, disperse at high speed for 30 min, add thixotropic agent I, control the rotation speed at 1000-1500 r / min, evacuate to -0.08 MPa to -0.1 MPa, and stir for 30-60 min to obtain component A.

[0029] (2) Add curing agent, coupling agent II, and toughening agent II to the reactor, and stir evenly at a speed of 1000-1500 r / min. Then add thermally conductive and flame-retardant filler II at 1200-2500 r / min and disperse at high speed for 30 min. Add thixotropic agent II and stir at a speed of 1000-1500 r / min. Vacuum at -0.08 MPa to -0.1 MPa and stir for 30-60 min to obtain component B.

[0030] (3) When using, simply mix component A and component B.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] (1) The rapid curing thermally conductive and flame-retardant epoxy adhesive of the present invention uses polyurethane epoxy resin with an epoxy equivalent of 210-250 g / mol and a viscosity of 40000-60000 mPa·s, and the epoxy resin and polyurethane epoxy resin are in a weight ratio of (14-25):(5-20). The epoxy adhesive formed has a certain toughness after rapid curing. It has excellent aging resistance and good shear strength when fixing the battery cell and the bottom water-cooling plate. It is suitable for bonding with a variety of materials and has excellent shear resistance.

[0033] (2) The fast-curing thermally conductive and flame-retardant epoxy adhesive of the present invention uses a combination of amine curing agent and polythiol curing agent, and adopts a weight ratio of (18-23):(9-15), which improves the curing speed of the adhesive, shortens the working time, maintains the toughness of the adhesive, and avoids the embrittlement problem caused by excessively fast curing.

[0034] (3) The rapid curing thermally conductive and flame-retardant epoxy adhesive of the present invention uses a combination of thermally conductive and flame-retardant fillers with a particle size of 10-18μm and a particle size of 20-25μm. The epoxy adhesive prepared has a high thermal conductivity, which can enable the heat generated by the battery module to be rapidly exchanged with the cooling system.

[0035] (4) The rapid curing thermally conductive and flame-retardant epoxy adhesive of the present invention uses a weight ratio of (55-70):(0-1) for thermally conductive and flame-retardant filler and dispersant in component A. The prepared epoxy adhesive has stable performance during storage and is not prone to sedimentation, delamination, or yellowing. It has the effect of temperature and humidity resistance and can withstand extreme cold and heat cycles.

[0036] (5) The fast-curing thermally conductive and flame-retardant epoxy adhesive described in this invention is used to fix the battery cell and the bottom water-cooling plate. It is suitable for power battery PACK modules. It has good bonding effect on untreated PI and PET films, excellent aging performance, stable storage period, resistance to high and low temperature shock, high thermal conductivity, and can achieve V0 flame retardant performance. Its fast curing properties also meet the requirements of early-stage production processes. Detailed Implementation

[0037] Example 1

[0038] A fast-curing, thermally conductive, and flame-retardant epoxy adhesive is prepared from raw materials comprising component A and component B. Component A, by weight, comprises: 20 parts epoxy resin, 7 parts modified epoxy resin, 6 parts toughening agent I, 5 parts diluent, 1 part coupling agent I, 0.6 parts additive, 0.4 parts thixotropic agent I, and 60 parts thermally conductive and flame-retardant filler I. Component B, by weight, comprises: 29 parts curing agent, 0.4 parts accelerator, 4 parts toughening agent II, 1 part coupling agent II, 0.6 parts thixotropic agent II, and 65 parts thermally conductive and flame-retardant filler II.

[0039] The epoxy resin is bisphenol A epoxy resin with an epoxy equivalent of 184-195 g / mol, a viscosity of 12000 mPa·s at 25°C, and is designated as type 618 epoxy resin.

[0040] The modified epoxy resin is a polyurethane modified epoxy resin with an epoxy equivalent of 210-250 g / mol and a viscosity of 40000-60000 mPa·s at 25℃. It was purchased from Complex High-Tech Materials (Shanghai) Co., Ltd., and the model is EPU-133L.

[0041] The diluent is 1,4-butanediol diglycidyl ether, the toughening agent I is Kanekazuchi MX-154 (Japan), and the toughening agent II is a CTBN modified toughening agent.

[0042] The thermally conductive and flame-retardant fillers I and II both have a thermal conductivity of 1.2-1.5 W / mK, a D50 of 8-10 μm, and an oil absorption of 20-30 g / 100 g. They were purchased from Dongchao New Materials Co., Ltd. in Dongguan City, Guangdong Province, and the model number is DCS-1500.

[0043] The coupling agent I is KH-560, and the coupling agent II is KH-550.

[0044] The additive is a dispersant, model BYK-9076. The thixotropic agents I and II are both Wacker H-17.

[0045] The accelerator is Wacker K54.

[0046] The curing agent is a combination of polyamide curing agent and polythiol curing agent in a weight ratio of 20:9. The polythiol was purchased from Toray Industries, Japan (QE340M), and the polyamide was purchased from Shanghai Junjiang Technology Co., Ltd. (model D8140).

[0047] A method for preparing a fast-curing, thermally conductive, and flame-retardant epoxy adhesive includes the following steps:

[0048] (1) Add epoxy resin, modified epoxy resin, diluent, and additives to a reaction vessel, control the rotation speed at 1200 r / min, control the temperature at 50℃, and stir thoroughly. Then add coupling agent I, toughening agent I, and thermally conductive and flame-retardant filler I, control the rotation speed at 2000 r / min, disperse at high speed for 30 min, add thixotropic agent I, control the rotation speed at 1200 r / min, evacuate to -0.1 MPa, and stir for 40 min to obtain component A.

[0049] (2) Add curing agent, coupling agent II and toughening agent II into the reactor, control the speed to 1200 r / min and stir evenly, then add thermally conductive and flame-retardant filler II at 2000 r / min and disperse at high speed for 30 min, add thixotropic agent II and control the speed to 1200 r / min, evacuate to -0.1 MPa and stir for 50 min to obtain component B;

[0050] (3) When using, simply mix component A and component B at a mass ratio of 1:1.

[0051] Example 2

[0052] A fast-curing, thermally conductive, and flame-retardant epoxy adhesive is prepared using the same steps as in Example 1, except that the raw materials for component A, by weight, include: 15 parts epoxy resin, 12 parts modified epoxy resin, 6 parts toughening agent I, 7 parts diluent, 1.5 parts coupling agent I, 0.6 parts additives, 0.4 parts thixotropic agent I, and 80 parts thermally conductive and flame-retardant filler I; the raw materials for component B, by weight, include: 29 parts curing agent, 0.4 parts accelerator, 4 parts toughening agent II, 2 parts coupling agent II, 0.6 parts thixotropic agent II, and 80 parts thermally conductive and flame-retardant filler II.

[0053] Example 3

[0054] A fast-curing, thermally conductive, and flame-retardant epoxy adhesive is prepared using the same steps as in Example 1, except that the raw materials for component A, by weight, include: 15 parts epoxy resin, 12 parts modified epoxy resin, 5 parts toughening agent I, 5 parts diluent, 2 parts coupling agent I, 0.6 parts additives, 0.4 parts thixotropic agent I, and 60 parts thermally conductive and flame-retardant filler I; the raw materials for component B, by weight, include: 33 parts curing agent, 0.4 parts accelerator, 3 parts toughening agent II, 1 part coupling agent II, 0.6 parts thixotropic agent II, and 62 parts thermally conductive and flame-retardant filler II.

[0055] The modified epoxy resin is a polyurethane modified epoxy resin with an epoxy equivalent of 240-280 g / mol and a viscosity of 20000-35000 mPa·s at 25℃. It was purchased from Complex High-Tech Materials (Shanghai) Co., Ltd., and the model is EPU-302.

[0056] The curing agent is a combination of polyamide curing agent and polythiol curing agent in a weight ratio of 18:15.

[0057] The thermally conductive and flame-retardant fillers I and II have a thermal conductivity of 1.7-2.2 W / mK, a D50 of 10-18 μm, and an oil absorption of 10-19 g / 100 g. They were purchased from Dongchao New Materials Co., Ltd. in Dongguan City, Guangdong Province, and the model number is DCS-2000.

[0058] Example 4

[0059] A fast-curing, thermally conductive, and flame-retardant epoxy adhesive is prepared using the same steps as in Example 1, except that the raw materials for component A, by weight, include: 18 parts epoxy resin, 9 parts modified epoxy resin, 5 parts toughening agent I, 5 parts diluent, 2 parts coupling agent I, 0.6 parts additives, 0.4 parts thixotropic agent I, and 60 parts thermally conductive and flame-retardant filler I; the raw materials for component B, by weight, include: 33 parts curing agent, 0.4 parts accelerator, 3 parts toughening agent II, 1 part coupling agent II, 0.6 parts thixotropic agent II, and 62 parts thermally conductive and flame-retardant filler II.

[0060] The toughening agent I is PB-1300, which is polyisobutylene purchased from Daelim, South Korea.

[0061] The modified epoxy resin is a polyurethane modified epoxy resin with an epoxy equivalent of 590-630 g / mol and a viscosity of 40000-70000 mPa·s at 25℃. It was purchased from Complex High-Tech Materials (Shanghai) Co., Ltd., and the model is EPU-300S.

[0062] The curing agent is a combination of polyamide curing agent and polythiol curing agent in a weight ratio of 23:10.

[0063] The thermally conductive and flame-retardant filler I has a thermal conductivity of 1.7-2.2 W / mK, a D50 of 10-18 μm, and an oil absorption of 10-19 g / 100 g. It was purchased from Dongguan Dongchao New Materials Co., Ltd. in Guangdong Province, and its model is DCS-2000. The thermally conductive and flame-retardant filler II has a thermal conductivity of 2.8-3.2 W / mK, a D50 of 20-25 μm, and an oil absorption of 10-19 g / 100 g. It was purchased from Dongguan Dongchao New Materials Co., Ltd. in Guangdong Province, and its model is DCS-3000.

[0064] Performance testing

[0065] The A and B components of the prepared epoxy adhesive were mixed and applied to the substrate with a coating thickness of 0.1 mm. After curing at room temperature of 25°C, the mixture was tested.

[0066] 1. Workable time: The workable time was recorded after the epoxy adhesive prepared in Examples 1-4 was applied to the substrate and the time was recorded after curing at room temperature of 25°C.

[0067] 2. Hardness: The hardness of the epoxy adhesives prepared in Examples 1-4 was tested according to GB / T531.1-2008 standard.

[0068] 3. Thermal conductivity: The thermal conductivity of the epoxy adhesives prepared in Examples 1-4 was tested according to ASTM D5470 standard.

[0069] 4. Flame retardancy rating: The flame retardancy rating of the epoxy adhesives prepared in Examples 1-4 was tested according to UL94 standard.

[0070] 5. Dielectric strength: The dielectric strength of the epoxy adhesives prepared in Examples 1-4 was tested according to GB / T1695-81 standard.

[0071] 6. Volume resistivity: The volume resistivity of the epoxy adhesives prepared in Examples 1-4 was tested according to GB / T1692-92 standard.

[0072] 7. Shear strength: The shear strength of the epoxy adhesives prepared in Examples 1-4 in 3003Al-3003Al, PI-PI, and PET-PET substrates was tested according to GB / T 7124-2008 standard.

[0073] 8. Double 85 aging: Aging at 85℃ and 85% humidity for 1500h, and testing the shear strength of the epoxy adhesives prepared in Examples 1-4 in 3003Al-3003Al substrates according to GB / T 7124-2008 standard.

[0074] 9. Thermal shock cycle: The epoxy adhesives prepared in Examples 1-4 were subjected to 200 thermal shock cycles in an environment of -40℃ to 150℃. The shear strength of the epoxy adhesives in 3003Al-3003Al substrates was tested in accordance with GB / T7124-2008 standard.

[0075] The test results are shown in Table 1.

[0076] Table 1

[0077]

Claims

1. A fast-curing, thermally conductive, flame-retardant epoxy adhesive, characterized in that, The preparation raw materials of the A component and the B component, the preparation raw materials of the A component include: epoxy resin 14-25 parts, modified epoxy resin 5-20 parts, toughening agent I 3-8 parts, diluent 3-6 parts, coupling agent I 0.5-2.5 parts, auxiliary agent 0-1 part, thixotropic agent I 0.3-1.5 parts, and heat-conducting and flame-retardant filler I 55-70 parts by weight; The epoxy resin is bisphenol A epoxy resin, the epoxy equivalent weight of the bisphenol A epoxy resin is 184-195 g / mol, and the viscosity at 25 DEG C is 12000-15000 mPa s; The modified epoxy resin is polyurethane modified epoxy resin, the epoxy equivalent weight of the polyurethane modified epoxy resin is 210-250 g / mol, and the viscosity at 25 DEG C is 40000-60000 mPa s; The preparation raw materials of the B component include: curing agent 20-35 parts, accelerator 0-1 part, toughening agent II 0.5-5 parts, coupling agent II 0.5-2.5 parts, thixotropic agent II 0.3-1 part, and heat-conducting and flame-retardant filler II 55-70 parts by weight; The curing agent is a combination of amine curing agent and polythiol curing agent, and the weight ratio of the amine curing agent to the polythiol curing agent is (18-23):(9-15). The amine curing agent is a polyamide curing agent.

2. The quick-curing, thermally conductive, flame-retardant epoxy adhesive of claim 1, wherein, The coupling agent II is amino-containing siloxane, and the amino-containing siloxane is selected from one or a combination of several of gamma-aminopropyl triethoxysilane, gamma-aminopropyl trimethoxysilane, and N-phenylaminomethyl triethoxysilane.

3. The quick curing, thermally conductive, flame retardant epoxy adhesive of claim 1, wherein, The auxiliary agent is selected from one or a combination of several of defoaming agent, antioxidant, and dispersant.

4. A process for the preparation of a fast curing, thermally conductive, flame retardant epoxy adhesive according to any one of claims 1 to 3, characterized in that, The method comprises the following steps: (1) the epoxy resin, the modified epoxy resin, the diluent, and the auxiliary agent are added into a reaction kettle, the rotation speed is controlled to be 1000-1500 r / min, the temperature is controlled to be 45-55 DEG C, and after stirring sufficiently, the coupling agent I, the toughening agent I, and the heat-conducting and flame-retardant filler I are added, the rotation speed is controlled to be 1200 r / min-2500 r / min, high-speed dispersion is carried out for 30 min, the thixotropic agent I is added, the rotation speed is controlled to be 1000-1500 r / min, vacuum is drawn to-0.08 MPa~-0.1 MPa, and stirring is carried out for 30-60 min to obtain the A component; (2) the curing agent, the coupling agent II, and the toughening agent II are added into a reaction kettle, the rotation speed is controlled to be 1000-1500 r / min, and then the heat-conducting and flame-retardant filler II is added at 1200 r / min-2500 r / min, high-speed dispersion is carried out for 30 min, the thixotropic agent II is added, the rotation speed is controlled to be 1000-1500 r / min, vacuum is drawn to-0.08 MPa~-0.1 MPa, and stirring is carried out for 30-60 min to obtain the B component; (3) when used, the A component and the B component are mixed.

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