A two-component fast-curing thermally conductive epoxy structural adhesive and a preparation method thereof

Abstract

The invention discloses a two-component fast-curing heat-conducting epoxy structural adhesive and a preparation method thereof. The two-component fast-curing heat-conducting epoxy structural adhesive comprises a component A and a component B. The component A comprises the following raw materials in parts by weight: 20-30 parts of a low-viscosity epoxy resin, 1-5 parts of an epoxy diluent, 2-10 parts of acrylic acid-terminated polybutadiene, 50-70 parts of a filler, 0.1-0.5 parts of a dispersant, 1-5 parts of a thixotropic agent, and 0.1-0.5 parts of a toner; and the component B comprises the following raw materials in parts by weight: 10-15 parts of a modified rubber, 10-15 parts of a low-viscosity polyamide curing agent, 2-5 parts of a fatty primary amine curing agent, 1-3 parts of a phenolic accelerator, 50-70 parts of a filler, and 1-5 parts of a thixotropic agent.

Description

Technical Field

[0001] The invention relates to the field of thermally conductive epoxy structural adhesive, and more specifically to a two-component rapidly curable thermally conductive epoxy structural adhesive and a preparation method thereof. Background Art

[0002] With the development of integrated circuits and assembly technology in the electronics industry, the size of electronic components and logic circuits tends to be miniaturized, and their development towards multifunctionality and integration is bound to cause a significant increase in heat generation, which places high demands on the thermal conductivity of bonding and packaging materials to prevent excessive heat from damaging electronic systems. High-performance electronic devices need to use materials with high thermal conductivity to dissipate heat. Traditional structural adhesives usually lack effective thermal conductivity, which leads to thermal management problems in bonding structures and potential performance limitations.

[0003] In this context, thermally conductive structural adhesive has been developed as a new type of thermally conductive material. Through structural design and the use of new materials, it effectively improves the thermal conductivity. It can maximize the thermal conductivity, high temperature stability and impact resistance while ensuring material performance. It has been widely used in heat dissipation and connection in electronics, communications, automobiles, aviation and other fields.

[0004] Under such conditions, the curing performance, bonding performance, high temperature resistance, and flame retardancy of the adhesive are particularly important. Therefore, it is of great significance to develop a room temperature fast curing, thermally conductive epoxy electronic structural adhesive with excellent comprehensive performance. Summary of the invention

[0005] In view of the above-mentioned defects of the prior art, the present invention provides a two-component fast-curing thermally conductive epoxy structural adhesive and a preparation method thereof.

[0006] In order to achieve the purpose of the present invention, the present invention is implemented by the following technical scheme: a two-component fast-curing thermally conductive epoxy structural adhesive, comprising component A and component B, wherein component A comprises the following raw materials in parts by weight: 20-30 parts of low-viscosity epoxy resin, 1-5 parts of epoxy diluent, 2-10 parts of acrylic acid-terminated polybutadiene, 50-70 parts of filler, 0.1-0.5 parts of dispersant, and 1-5 parts of thixotropic agent;

[0007] The B component comprises the following raw materials in parts by weight: 10-15 parts of modified rubber, 10-15 parts of low-viscosity polyamide curing agent, 2-5 parts of fatty primary amine curing agent, 1-3 parts of phenolic accelerator, 50-70 parts of filler, 1-5 parts of thixotropic agent and 0.1-0.5 parts of color powder.

[0008] In the two-component fast-curing thermally conductive epoxy structural adhesive of the present invention, the low-viscosity epoxy resin is a liquid bisphenol A epoxy resin, and the epoxy diluent is at least one of cardanol glycidyl ether, C12-14 fatty glycidyl ether or 1,4-butanediol diglycidyl ether.

[0009] In the two-component fast-curing heat-conductive epoxy structural adhesive of the present invention, the acrylic acid-terminated polybutadiene is a mixture of one or more of non-double-terminated acrylic acid-terminated polybutadiene and multifunctional acrylic acid polybutadiene.

[0010] In the two-component fast-curing thermally conductive epoxy structural adhesive of the present invention, the filler is aluminum hydroxide, angular silica powder or aluminum oxide, and the filler has a particle size of 8-10 microns, 15-20 microns and 50 microns, or a mixture of the above-mentioned different particle sizes;

[0011] The dispersant is at least one of BYK9076 dispersant and BYK-118E dispersant, the toner is pigment carbon black, and the thixotropic agent is fumed silica.

[0012] In the two-component fast-curing thermally conductive epoxy structural adhesive of the present invention, the modified rubber is an amino-terminated modified rubber, and the low-viscosity polyamide curing agent is a low-molecular-weight polyamide curing agent with a viscosity of less than 1000 cps and an active hydrogen equivalent of less than 200 g / eq.

[0013] In the two-component fast-curing heat-conductive epoxy structural adhesive of the present invention, the fatty primary amine curing agent is a mixture of one or more of diethylenetriamine, triethylenetetramine and tetraethylenepentamine.

[0014] In the two-component fast-curing thermally conductive epoxy structural adhesive of the present invention, the phenolic accelerator is 2,4,6-tris(dimethylaminomethyl)-phenol DMP30.

[0015] In order to achieve the purpose of the present invention, the present invention is implemented by another technical solution: a preparation method of a two-component fast-curing thermally conductive epoxy structural adhesive, based on the above-mentioned two-component fast-curing thermally conductive epoxy structural adhesive, comprising the following steps:

[0016] Step 1: Weigh low-viscosity epoxy resin, epoxy diluent, acrylic acid-terminated polybutadiene, filler, dispersant, and thixotropic agent according to the above weight parts, use a stirrer to mix the low-viscosity epoxy resin, epoxy diluent, acrylic acid-terminated polybutadiene and dispersant, and then add the filler and thixotropic agent in sequence to prepare component A;

[0017] Step 2: Weigh the modified rubber, low viscosity polyamide curing agent, fatty primary amine curing agent, phenolic accelerator, filler, thixotropic agent and color powder according to the above weight parts, use a stirrer to mix the modified rubber, low viscosity polyamide curing agent, fatty primary amine curing agent and phenolic accelerator, and then add the filler, thixotropic agent and color powder in sequence to prepare component B;

[0018] Step 3: Mix the prepared component A and component B in a volume ratio of 2:1 to prepare a two-component fast-curing thermally conductive epoxy structural adhesive.

[0019] In the preparation method of the two-component fast-curing thermally conductive epoxy structural adhesive of the present invention, in step 1, the mixer is a double planetary vacuum mixer, and step 1 is specifically as follows:

[0020] The low-viscosity epoxy resin, epoxy diluent, acrylic acid-terminated polybutadiene and dispersant are stirred at a speed of 20 r / min, dispersed at a speed of 250 r / min, stirred at a temperature less than or equal to 40° C., and stirred for 15 min.

[0021] After adding the filler, the stirring speed is 20r / min, the dispersion speed is 250r / min, the stirring temperature is less than or equal to 40°C, and the stirring time is 15min;

[0022] After adding the thixotropic agent, the stirring speed is 25 r / min, the dispersion speed is 600 r / min, the stirring temperature is less than or equal to 50°C, and the stirring time is 60 min;

[0023] After the stirring was completed, the vacuum was turned on, the gauge pressure was -0.09 MPa, the stirring speed was 20 r / min, the dispersion speed was 200 r / min, and the stirring was continued for 30 min to obtain component A.

[0024] In the preparation method of the two-component fast-curing thermally conductive epoxy structural adhesive of the present invention, in step 2, the mixer is a double planetary vacuum mixer, and step 2 is specifically as follows:

[0025] The modified rubber, low-viscosity polyamide curing agent, fatty primary amine curing agent and phenolic accelerator are stirred at a speed of 20 r / min, a dispersion speed of 250 r / min, a stirring temperature of less than or equal to 40° C., and a stirring time of 15 min.

[0026] After adding the filler, the stirring speed is 20r / min, the dispersion speed is 250r / min, the stirring temperature is less than or equal to 40°C, and the stirring time is 15min;

[0027] After adding the thixotropic agent and color powder, the stirring speed is 25 r / min, the dispersion speed is 600 r / min, the stirring temperature is less than or equal to 50°C, and the stirring time is 60 min;

[0028] After the stirring was completed, the vacuum was turned on, the gauge pressure was -0.09 MPa, the stirring speed was 20 r / min, the dispersion speed was 200 r / min, and the stirring was continued for 30 min to obtain component B.

[0029] The implementation of the two-component fast-curing heat-conducting epoxy structural adhesive and the preparation method thereof of the present invention has the following beneficial effects: the two-component fast-curing heat-conducting epoxy structural adhesive prepared by the method of the present invention can achieve rapid positioning, and has excellent heat aging resistance and wet heat performance. The curing time is fast, the product production cycle is shortened, and the cost is saved. And the thermal conductivity is good, and the heat can be quickly conducted out. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0031] Figure 1 The present invention is a schematic flow chart of a method for preparing a two-component fast-curing thermally conductive epoxy structural adhesive. DETAILED DESCRIPTION

[0032] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0033] In the present application, the two-component fast-curing thermally conductive epoxy structural adhesive comprises component A and component B, wherein component A comprises the following raw materials in parts by weight: 20-30 parts of low-viscosity epoxy resin, 1-5 parts of epoxy diluent, 2-10 parts of acrylic acid-terminated polybutadiene, 50-70 parts of filler, 0.1-0.5 parts of dispersant, and 1-5 parts of thixotropic agent;

[0034] The B component comprises the following raw materials in parts by weight: 10-15 parts of modified rubber, 10-15 parts of low-viscosity polyamide curing agent, 2-5 parts of fatty primary amine curing agent, 1-3 parts of phenolic accelerator, 50-70 parts of filler, 1-5 parts of thixotropic agent and 0.1-0.5 parts of color powder.

[0035] In a preferred embodiment, the component A further comprises the following raw materials in parts by weight: 0.5-1 part of KH-560 silane coupling agent, specifically γ-glycidyloxypropyltrimethoxysilane.

[0036] Preferably, the low viscosity epoxy resin is a liquid bisphenol A epoxy resin, and the epoxy diluent is at least one of cardanol glycidyl ether, C12-14 fatty glycidyl ether or 1,4-butanediol diglycidyl ether.

[0037] Preferably, the acrylic acid-terminated polybutadiene is a mixture of one or more of non-dual-terminated acrylic acid-terminated polybutadiene and multifunctional acrylic acid polybutadiene.

[0038] Preferably, the filler is aluminum hydroxide, angular silicon powder or aluminum oxide, and the filler is one of 8-10 microns, 15-20 microns and 50 microns in particle size or a mixture of the above several different particle sizes.

[0039] The dispersant is at least one of BYK9076 dispersant and BYK-118E dispersant, the toner is pigment carbon black, and the thixotropic agent is fumed silica.

[0040] Preferably, the modified rubber is an amino-terminated modified rubber, and the low-viscosity polyamide curing agent is a low-molecular-weight polyamide curing agent with a viscosity of less than 1000 cps and an active hydrogen equivalent of less than 200 g / eq.

[0041] Preferably, the fatty primary amine curing agent is a mixture of one or more of diethylenetriamine, triethylenetetramine and tetraethylenepentamine.

[0042] Preferably, the phenolic accelerator is 2,4,6-tris(dimethylaminomethyl)-phenol DMP30.

[0043] like Figure 1 As shown, the present application also discloses a method for preparing a two-component fast-curing thermally conductive epoxy structural adhesive, based on the above-mentioned two-component fast-curing thermally conductive epoxy structural adhesive, comprising the following steps:

[0044] Step 1: Weigh low-viscosity epoxy resin, epoxy diluent, acrylic acid-terminated polybutadiene, filler, dispersant, and thixotropic agent according to the above weight parts, use a stirrer to mix the low-viscosity epoxy resin, epoxy diluent, acrylic acid-terminated polybutadiene and dispersant, and then add the filler and thixotropic agent in sequence to prepare component A;

[0045] Step 2: Weigh the modified rubber, low viscosity polyamide curing agent, fatty primary amine curing agent, phenolic accelerator, filler, thixotropic agent and color powder according to the above weight parts, use a stirrer to mix the modified rubber, low viscosity polyamide curing agent, fatty primary amine curing agent and phenolic accelerator, and then add the filler, thixotropic agent and color powder in sequence to prepare component B;

[0046] Step 3: Mix the prepared component A and component B in a volume ratio of 2:1 to prepare a two-component fast-curing thermally conductive epoxy structural adhesive.

[0047] Specifically, in step 1, the mixer is a double planetary vacuum mixer, and step 1 is specifically as follows:

[0048] The low-viscosity epoxy resin, epoxy diluent, acrylic acid-terminated polybutadiene and dispersant are stirred at a speed of 20 r / min, dispersed at a speed of 250 r / min, stirred at a temperature less than or equal to 40° C., and stirred for 15 min.

[0049] After adding the filler, the stirring speed is 20r / min, the dispersion speed is 250r / min, the stirring temperature is less than or equal to 40°C, and the stirring time is 15min;

[0050] After adding the thixotropic agent, the stirring speed is 25 r / min, the dispersion speed is 600 r / min, the stirring temperature is less than or equal to 50°C, and the stirring time is 60 min;

[0051] After the stirring was completed, the vacuum was turned on, the gauge pressure was -0.09 MPa, the stirring speed was 20 r / min, the dispersion speed was 200 r / min, and the stirring was continued for 30 min to obtain component A.

[0052] Specifically, in step 2, the mixer is a double planetary vacuum mixer, and step 2 is specifically as follows:

[0053] The modified rubber, low-viscosity polyamide curing agent, fatty primary amine curing agent and phenolic accelerator are stirred at a speed of 20 r / min, a dispersion speed of 250 r / min, a stirring temperature of less than or equal to 40° C., and a stirring time of 15 min.

[0054] After adding the filler, the stirring speed is 20r / min, the dispersion speed is 250r / min, the stirring temperature is less than or equal to 40°C, and the stirring time is 15min;

[0055] After adding the thixotropic agent and color powder, the stirring speed is 25 r / min, the dispersion speed is 600 r / min, the stirring temperature is less than or equal to 50°C, and the stirring time is 60 min;

[0056] After the stirring was completed, the vacuum was turned on, the gauge pressure was -0.09 MPa, the stirring speed was 20 r / min, the dispersion speed was 200 r / min, and the stirring was continued for 30 min to obtain component B.

[0057] Embodiment 1

[0058] The present embodiment provides a two-component fast-curing thermally conductive epoxy structural adhesive, including component A and component B, wherein the volume ratio of component A to component B is 2:1, and component A includes the following raw materials in parts by weight: 30 parts of low-viscosity epoxy resin REP 1310, 3 parts of epoxy diluent, 8 parts of EPMAT (acrylic-terminated polybutadiene), 0.3 parts of BYK 9076 (dispersant), 1 part of KH560 (KH-560 silane coupling agent), 57 parts of aluminum hydroxide (filler), and 2 parts of thixotropic agent.

[0059] Component B includes the following raw materials in parts by weight: 12 parts of Aradur 350 (low viscosity polyamide curing agent), 13 parts of ATBN1300X16 (modified rubber), 4 parts of DETA (fatty primary amine curing agent), 1 part of DMP30 (phenolic accelerator), 66 parts of aluminum hydroxide (filler), 2.5 parts of thixotropic agent, and 0.1 parts of color powder.

[0060] This embodiment also provides a method for preparing a two-component fast-curing thermally conductive epoxy structural adhesive, comprising the following steps:

[0061] 30 parts of low-viscosity epoxy resin REP1310, 3 parts of diluent, 8 parts of EPMAT, 0.3 parts of byk 9076, and 1 part of KH560 were added to the material cup respectively, and the speed was set to 900rpm for 30s + 1200rpm for 120s. After stirring, 57 parts of aluminum hydroxide and 2 parts of thixotropic agent were added, and the speed was set to 900rpm for 30s + 1200rpm for 120s. After stirring, the vacuum degree was set to 0.07-0.1MPa, and stirred at 1200rpm for 150s. After cooling to room temperature, the main agent component A was obtained;

[0062] 12 parts of Aradur 350, 13 parts of ATBN1300X16, 4 parts of DETA and 1 part of DMP30 were added to the material cup respectively, and the speed was set to 900rpm for 30s+1200rmp for 120s. After the stirring was completed, 66 parts of aluminum hydroxide, 2.5 parts of thixotropic agent and 0.1 part of color powder were added, and the speed was set to 900rpm for 30s+1200rmp for 120s. After the stirring was completed, the vacuum degree was set to maintain at 0.07-0.1MPa, and the mixture was stirred at 1200rmp for 150s. After cooling to room temperature, the curing agent component B was obtained.

[0063] The prepared main agent component and curing agent component are packaged in a volume ratio of 2:1 to obtain an epoxy thermal conductive structural adhesive that can achieve rapid positioning and curing at room temperature.

[0064] Embodiment 2

[0065] The present embodiment provides a two-component fast-curing thermally conductive epoxy structural adhesive, including component A and component B, wherein the volume ratio of component A to component B is 2:1, and component A includes the following raw materials in parts by weight: 38 parts of low-viscosity epoxy resin REP 1310, 3 parts of diluent, 0.3 parts of BYK9076, 1 part of KH560, 57 parts of aluminum hydroxide, and 2 parts of thixotropic agent.

[0066] Component B includes the following raw materials in parts by weight: 12 parts of Aradur 350, 13 parts of ATBN 1300X16, 4 parts of DETA, 1 part of DMP30, 66 parts of aluminum hydroxide, 2.5 parts of thixotropic agent, and 0.1 part of color powder.

[0067] This embodiment also provides a method for preparing a two-component fast-curing thermally conductive epoxy structural adhesive, comprising the following steps:

[0068] 38 parts of low-viscosity epoxy resin REP1310, 3 parts of diluent, 0.3 parts of byk9076, and 1 part of KH560 were added to the material cup respectively, and the speed was set to 900rpm for 30s+1200rmp for 120s. After stirring, 57 parts of aluminum hydroxide and 2 parts of thixotropic agent were added, and the speed was set to 900rpm for 30s+1200rmp for 120s. After stirring, the vacuum degree was set to 0.07-0.1MPa, and stirred at 1200rmp for 150s. After cooling to room temperature, the main agent component A was obtained;

[0069] 12 parts of Aradur 350, 13 parts of ATBN1300X16, 4 parts of DETA and 1 part of DMP30 were added to the material cup respectively, and the speed was set to 900rpm for 30s+1200rmp for 120s. After the stirring was completed, 66 parts of aluminum hydroxide, 2.5 parts of thixotropic agent and 0.1 part of color powder were added, and the speed was set to 900rpm for 30s+1200rmp for 120s. After the stirring was completed, the vacuum degree was set to maintain at 0.07-0.1MPa, and the mixture was stirred at 1200rmp for 150s. After cooling to room temperature, the curing agent component B was obtained.

[0070] The prepared main agent component and curing agent component are packaged in a volume ratio of 2:1 to obtain an epoxy thermal conductive structural adhesive that can achieve rapid positioning and curing at room temperature.

[0071] Embodiment 3

[0072] The present embodiment provides a two-component fast-curing thermally conductive epoxy structural adhesive, including component A and component B, wherein the volume ratio of component A to component B is 2:1, and component A includes the following raw materials in parts by weight: 33 parts of low-viscosity epoxy resin REP1310, 3 parts of diluent and 4 parts of EPMAT, 0.3 parts of BYK 9076, 1 part of KH560, 57 parts of aluminum hydroxide, and 2 parts of thixotropic agent.

[0073] Component B includes the following raw materials in parts by weight: 14 parts of Aradur 350, 13 parts of ATBN 1300X16, 2 parts of DETA, 1 part of DMP30, 66 parts of aluminum hydroxide, 2.5 parts of thixotropic agent, and 0.1 part of color powder.

[0074] This embodiment also provides a method for preparing a two-component fast-curing thermally conductive epoxy structural adhesive, comprising the following steps:

[0075] 33 parts of low-viscosity epoxy resin REP1310, 3 parts of diluent and 4 parts of EPMAT, 0.3 parts of byk 9076 and 1 part of KH560 were added to the material cup respectively, and the speed was set to 900rpm for 30s + 1200rpm for 120s. After stirring, 57 parts of aluminum hydroxide and 2 parts of thixotropic agent were added, and the speed was set to 900rpm for 30s + 1200rpm for 120s. After stirring, the vacuum degree was set to 0.07-0.1MPa, and stirred at 1200rpm for 150s. After cooling to room temperature, the main agent component A was obtained;

[0076] 14 parts of Aradur 350, 13 parts of ATBN1300X16, 2 parts of DETA and 1 part of DMP30 were added to the material cup respectively, and the speed was set to 900rpm for 30s+1200rmp for 120s. After the stirring was completed, 66 parts of aluminum hydroxide, 2.5 parts of thixotropic agent and 0.1 part of color powder were added, and the speed was set to 900rpm for 30s+1200rmp for 120s. After the stirring was completed, the vacuum degree was set to maintain at 0.07-0.1MPa, and the mixture was stirred at 1200rmp for 150s. After cooling to room temperature, the curing agent component B was obtained.

[0077] The prepared main agent component and curing agent component are packaged in a volume ratio of 2:1 to obtain an epoxy thermal conductive structural adhesive that can achieve rapid positioning and curing at room temperature.

[0078] Embodiment 4

[0079] The present embodiment provides a two-component fast-curing thermally conductive epoxy structural adhesive, including component A and component B, wherein the volume ratio of component A to component B is 2:1, and component A includes the following raw materials in parts by weight: 30 parts of low-viscosity epoxy resin REP 1310, 3 parts of diluent and 8 parts of EPMAT, 0.3 parts of BYK 9076, 1 part of KH560, 57 parts of silicon powder, and 2 parts of thixotropic agent.

[0080] Component B includes the following raw materials in parts by weight: Aradur 350, 13 parts of ATBN 1300X16, 4 parts of DETA, 1 part of DMP30, 66 parts of silica powder, 2.5 parts of thixotropic agent, and 0.1 part of color powder.

[0081] This embodiment also provides a method for preparing a two-component fast-curing thermally conductive epoxy structural adhesive, comprising the following steps:

[0082] 30 parts of low-viscosity epoxy resin REP 1310, 3 parts of diluent, 8 parts of EPMAT, 0.3 parts of byk 9076, and 1 part of KH560 were added to the material cup respectively, and the speed was set to 900rpm for 30s + 1200rpm for 120s. After stirring, 57 parts of silicon micropowder and 2 parts of thixotropic agent were added, and the speed was set to 900rpm for 30s + 1200rpm for 120s. After stirring, the vacuum degree was set to 0.07-0.1MPa, and stirred at 1200rpm for 150s. After cooling to room temperature, the main agent component A was obtained;

[0083] 12 parts of Aradur 350, 13 parts of ATBN 1300X16, 4 parts of DETA and 1 part of DMP30 were added to the material cup respectively, and the speed was set to 900rpm for 30s+1200rmp for 120s. After stirring, 66 parts of silicon powder, 2.5 parts of thixotropic agent and 0.1 part of color powder were added, and the speed was set to 900rpm for 30s+1200rmp for 120s. After stirring, the vacuum degree was set to 0.07-0.1MPa, and stirred at 1200rmp for 150s. After cooling to room temperature, the curing agent component B was obtained.

[0084] The prepared main agent component and curing agent component are packaged in a volume ratio of 2:1 to obtain an epoxy thermal conductive structural adhesive that can achieve rapid positioning and curing at room temperature.

[0085] Application examples:

[0086] The samples prepared in the examples were subjected to the following tests:

[0087] (1) 1h / 72h bonding strength:

[0088] Sample preparation: Mix component A and component B in a volume ratio of 2:1. Drop the mixed glue on a 6061 aluminum sheet that has been sanded and marked with lines. The thickness of the glue layer is controlled by 250-micron glass beads. Curing at room temperature for 1h / 72h will give the test sample.

[0089] Test requirements: The prepared samples were tested using a universal material testing machine at room temperature. The process was based on standard GB / T 7124-2008. The results are shown in Table 1.

[0090] (2) Thermal conductivity:

[0091] Sample preparation: Mix component A and component B in a volume ratio of 2:1, pour the mixed glue into the silicone mold, and cure at room temperature for 24 hours to obtain the test sample. Sample requirements: diameter 30mm, thickness ≤5mm, and smooth surface.

[0092] Coat a layer of thermal conductive silicone grease on the surface of the prepared sample, then put it into the equipment to start the test. Each test process is carried out according to the standard ASTM D5470. The equipment used for the test is Xiangtan Instrument DRL-V thermal conductivity tester, with a cold pole temperature of 30℃, a hot pole temperature of 70℃, and a test pressure of 200N. The results are shown in Table 1.

[0093] Heat and humidity resistance

[0094] Sample preparation: Mix component A and component B in a volume ratio of 2:1, drop the mixed glue on a 6061 aluminum sheet that has been sanded and marked with lines, the glue layer thickness is 250 microns, and cure at room temperature for 72 hours to obtain the test sample. Place the prepared sample in an 85℃85RH% environmental chamber for 1000 hours and then test it.

[0095] Test requirements: The prepared samples were tested using a universal material testing machine at room temperature. The process was based on standard GB / T 7124-2008. The results are shown in Table 1.

[0096] Long-term heat aging resistance

[0097] Sample preparation: Mix component A and component B in a volume ratio of 2:1, drop the mixed glue on a 6061 aluminum sheet that has been sanded and marked with lines, the glue layer thickness is 250 microns, and cure at room temperature for 72 hours to obtain the test sample. Place the prepared sample in a 150℃ heat aging box for 1000 hours before testing.

[0098] Test requirements: The prepared samples were tested using a universal material testing machine at room temperature. The process was based on standard GB / T 7124-2008. The results are shown in Table 1.

[0099] Table 1 Test results of various embodiments

[0100]

[0101] According to the data in Table 1, it can be seen from Example 1 and Example 2 that when acrylate-terminated polybutadiene and DETA (here as primary amine) exist at the same time, the operating strength of 3Mpa can be reached within 1 hour, which can meet the downstream operating scenarios. At the same time, it is found that when only DETA exists, the primary amine only acts as a room temperature curing agent and cannot provide a faster operating strength within 1 hour.

[0102] From the 72h shear strength, it can be seen that the introduction of strong polar groups such as acrylates can achieve excellent adhesion to metal substrates. At the same time, the introduction of long polybutadiene chains improves the toughness of the epoxy system and greatly improves the tensile shear strength of the thermal conductive epoxy structural adhesive.

[0103] The above description is only a preferred embodiment of the present invention, and does not limit the implementation mode and protection scope of the present invention. For those skilled in the art, it should be aware that all solutions obtained by equivalent substitutions and obvious changes made using the contents of the specification of the present invention should be included in the protection scope of the present invention.

Claims

1. A two-component fast-curing thermally conductive epoxy structural adhesive, characterized in that: The method comprises component A and component B, wherein component A comprises the following raw materials in parts by weight: 20-30 parts of low-viscosity epoxy resin, 1-5 parts of epoxy diluent, 2-10 parts of acrylic acid-terminated polybutadiene, 50-70 parts of filler, 0.1-0.5 parts of dispersant, and 1-5 parts of thixotropic agent; The B component comprises the following raw materials in parts by weight: 10-15 parts of modified rubber, 10-15 parts of low-viscosity polyamide curing agent, 2-5 parts of fatty primary amine curing agent, 1-3 parts of phenolic accelerator, 50-70 parts of filler, 1-5 parts of thixotropic agent and 0.1-0.5 parts of color powder.

2. The two-component fast-curing thermally conductive epoxy structural adhesive according to claim 1, characterized in that: The low-viscosity epoxy resin is a liquid bisphenol A epoxy resin, and the epoxy diluent is at least one of cardanol glycidyl ether, C12-14 fatty glycidyl ether or 1,4-butanediol diglycidyl ether.

3. The two-component fast-curing thermally conductive epoxy structural adhesive according to claim 1, characterized in that: The acrylic acid-terminated polybutadiene is a mixture of one or more of non-double-terminated acrylic acid-terminated polybutadiene and multifunctional acrylic acid polybutadiene.

4. The two-component fast-curing thermally conductive epoxy structural adhesive according to claim 1, characterized in that: The filler is aluminum hydroxide, angular silicon powder or aluminum oxide, and the filler has a particle size of 8-10 microns, 15-20 microns and 50 microns, or a mixture of the above several different particle sizes; The dispersant is at least one of BYK9076 dispersant and BYK-118E dispersant, the toner is pigment carbon black, and the thixotropic agent is fumed silica.

5. The two-component fast-curing thermally conductive epoxy structural adhesive according to claim 1, characterized in that: The modified rubber is an amino-terminated modified rubber, and the low-viscosity polyamide curing agent is a low-molecular-weight polyamide curing agent with a viscosity of less than 1000 cps and an active hydrogen equivalent of less than 200 g / eq.

6. The two-component fast-curing thermally conductive epoxy structural adhesive according to claim 1, characterized in that: The fatty primary amine curing agent is a mixture of one or more of diethylenetriamine, triethylenetetramine and tetraethylenepentamine.

7. The two-component fast-curing thermally conductive epoxy structural adhesive according to claim 1, characterized in that: The phenolic accelerator is 2,4,6-tris(dimethylaminomethyl)-phenol DMP30.

8. A method for preparing a two-component fast-curing thermally conductive epoxy structural adhesive, based on the two-component fast-curing thermally conductive epoxy structural adhesive according to any one of claims 1 to 7, characterized in that: The following steps are involved: Step 1: Weigh low-viscosity epoxy resin, epoxy diluent, acrylic acid-terminated polybutadiene, filler, dispersant, and thixotropic agent according to the above weight parts, use a stirrer to mix the low-viscosity epoxy resin, epoxy diluent, acrylic acid-terminated polybutadiene and dispersant, and then add the filler and thixotropic agent in sequence to prepare component A; Step 2: Weigh the modified rubber, low viscosity polyamide curing agent, fatty primary amine curing agent, phenolic accelerator, filler, thixotropic agent and color powder according to the above weight parts, use a stirrer to mix the modified rubber, low viscosity polyamide curing agent, fatty primary amine curing agent and phenolic accelerator, and then add the filler, thixotropic agent and color powder in sequence to prepare component B; Step 3: Mix the prepared component A and component B in a volume ratio of 2:1 to prepare a two-component fast-curing thermally conductive epoxy structural adhesive.

9. The method for preparing a two-component fast-curing thermally conductive epoxy structural adhesive according to claim 8, characterized in that: In the step 1, the mixer is a double planetary vacuum mixer, and the step 1 is specifically as follows: The stirring speed of the low-viscosity epoxy resin, epoxy diluent, acrylic acid-terminated polybutadiene and dispersant is 20 r / min, the dispersion speed is 250 r / min, the stirring temperature is less than or equal to 40° C., and the stirring time is 15 min; After adding the filler, the stirring speed is 20 r / min, the dispersion speed is 250 r / min, the stirring temperature is less than or equal to 40° C., and the stirring time is 15 min; After adding the thixotropic agent, the stirring speed is 25 r / min, the dispersion speed is 600 r / min, the stirring temperature is less than or equal to 50°C, and the stirring time is 60 min; After the stirring was completed, the vacuum was turned on, the gauge pressure was -0.09 MPa, the stirring speed was 20 r / min, the dispersion speed was 200 r / min, and the stirring was continued for 30 min to obtain component A.

10. The method for preparing a two-component fast-curing thermally conductive epoxy structural adhesive according to claim 8, characterized in that: In the step 2, the mixer is a double planetary vacuum mixer, and the step 2 is specifically as follows: The modified rubber, low-viscosity polyamide curing agent, fatty primary amine curing agent and phenolic accelerator are stirred at a speed of 20 r / min, a dispersion speed of 250 r / min, a stirring temperature of less than or equal to 40° C., and a stirring time of 15 min; After adding the filler, the stirring speed is 20 r / min, the dispersion speed is 250 r / min, the stirring temperature is less than or equal to 40° C., and the stirring time is 15 min; After adding the thixotropic agent and color powder, the stirring speed is 25 r / min, the dispersion speed is 600 r / min, the stirring temperature is less than or equal to 50°C, and the stirring time is 60 min; After the stirring was completed, the vacuum was turned on, the gauge pressure was -0.09 MPa, the stirring speed was 20 r / min, the dispersion speed was 200 r / min, and the stirring was continued for 30 min to obtain component B.

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