A gradient-cured bonded polyaramid amorphous strip adhesive as well as a preparation method and application thereof
The polyarylamide amorphous ribbon adhesive, which is bonded by gradient curing, utilizes a compound of modified E51 epoxy resin, specific phenolic epoxy resin, and carboxyl-terminated nitrile rubber to construct a flexible and rigid cross-linked network. This solves the problem of easy cracking of epoxy resin adhesives during thermal cycling and achieves excellent adhesion at both low and high temperatures.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- 弘润清源(北京)科技有限责任公司
- Filing Date
- 2026-01-27
- Publication Date
- 2026-05-29
AI Technical Summary
Existing epoxy resin adhesives are difficult to maintain excellent adhesion at both low and high temperatures during thermal cycling, which can easily lead to cracking of amorphous ribbons. Existing modification methods cannot simultaneously improve shear strength at both low and high temperatures.
A gradient-curing adhesive for polyarylamide amorphous ribbons is developed by compounding modified E51 epoxy resin with a specific ratio of phenolic epoxy resin and carboxyl-terminated nitrile rubber to construct a flexible and rigid cross-linked network, thereby enhancing interfacial bonding. Polyarylamide and latent amine curing agents are added to control the curing temperature and rate.
By simultaneously improving the shear strength of the amorphous ribbon surface at room temperature, low temperature and high temperature, and ensuring that it does not crack after 30 thermal cycles, the stability of the interface bonding and the resistance to thermal cycling are achieved.
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Figure CN122104140A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of adhesive technology, specifically relating to a gradient-curing adhesive for polyarylamide amorphous tapes, its preparation method, and its application. Background Technology
[0002] Reliable bonding of amorphous ribbons is crucial for ensuring the performance of composite structures containing amorphous ribbons. As the core bonding material, the adhesive's performance directly determines the interfacial bonding strength and thermal cycling stability of the composite structure. Currently, epoxy resin adhesives are the most widely used type of adhesive in the field of amorphous ribbon bonding. However, the cross-linked structure formed after curing is a homogeneous rigid system, which is difficult to buffer or release directional stress concentration at the interface during thermal cycling, easily leading to interfacial cracking and inducing amorphous ribbon fragmentation.
[0003] To address the aforementioned problems of epoxy resin adhesives, existing technologies have attempted modification and optimization by introducing modified silicone resins, hyperbranched epoxy resins, or adding fillers such as silica. For example, Chinese patent CN115181524B discloses a silica / epoxy resin inorganic-organic hybrid adhesive, which exhibits good shear strength at high temperatures. Chinese patent CN108611036B discloses a cashew phenol glycidyl ether modified epoxy resin adhesive, which exhibits good shear strength at low temperatures.
[0004] However, existing technologies cannot maintain excellent adhesion at both low and high temperatures, which can easily lead to the generation and propagation of interfacial microcracks under thermal cycling conditions, and thus cause cracking failure of amorphous ribbons. Summary of the Invention
[0005] The purpose of this invention is to provide a gradient-curing adhesive for polyarylamide amorphous ribbons, its preparation method, and its application.
[0006] To achieve the above objectives, the present invention provides the following technical solution: The first aspect of this invention provides a gradient-curing adhesive for amorphous polyarylamide ribbons, comprising the following components in parts by weight: 1-5 parts of polyarylamide, modified E... The mixture comprises 55-65 parts of epoxy resin, 5-8 parts of compounded phenolic epoxy resin, 15-20 parts of reactive diluent, 1-2 parts of silane coupling agent, 0.5-1 part of antioxidant, 0.3-0.5 parts of heat stabilizer, and 3-5 parts of curing agent; the compounded phenolic epoxy resin includes phenolic epoxy resin F-44, phenolic epoxy resin F-51, and phenolic epoxy resin F-48; the modified E 51 epoxy resin is prepared by modifying E-51 epoxy resin with carboxyl-terminated butadiene-acrylonitrile rubber.
[0007] Preferably, the modified E The preparation method of 51 epoxy resin includes the following steps: (1) Heat 55-60 parts by weight of E-51 epoxy resin, stir, and keep warm; (2) Under nitrogen protection, add carboxyl-terminated butadiene-acrylonitrile rubber, raise the temperature to 120-125℃, and react at a constant temperature for 2.5-3 hours with stirring; (3) After the reaction is complete, the temperature is lowered to obtain modified E-51 epoxy resin.
[0008] Preferably, the carboxyl-terminated nitrile butadiene rubber comprises a first carboxyl-terminated nitrile butadiene rubber, a second carboxyl-terminated nitrile butadiene rubber, and a third carboxyl-terminated nitrile butadiene rubber in a mass ratio of 1:(1.3-1.5):(0.4-0.6).
[0009] Preferably, the first-terminal carboxyl-terminated nitrile butadiene rubber has a carboxyl content of 0.46-0.60 mol / kg and an acrylonitrile content of 16.0-22.0%; the second-terminal carboxyl-terminated nitrile butadiene rubber has a carboxyl content of 0.51-0.65 mol / kg and an acrylonitrile content of 22.1-27.0%; and the third-terminal carboxyl-terminated nitrile butadiene rubber has a carboxyl content of 0.58-0.65 mol / kg and an acrylonitrile content of 8.0-12.0%.
[0010] This invention uses E Modifying E-51 epoxy resin with carboxyl-terminated nitrile butadiene rubber (NBR) can improve the shear strength of the adhesive on the surface of amorphous ribbons at room temperature. Furthermore, modifying it with a specific ratio of first, second, and third NBRs can enhance its shear strength at high temperatures. Analysis shows that under these conditions, the carboxyl groups at the ends of the NBR undergo a ring-opening addition reaction with the epoxy groups on the E-51 epoxy resin molecular chain, forming a gradient flexible crosslinked network and a strong polar interfacial bond. By varying the acrylonitrile and carboxyl content of the three NBRs, a stable crosslinked network with both rigidity and toughness is constructed, while simultaneously strengthening the interfacial bond at high temperatures and preventing network relaxation and interfacial delamination.
[0011] Preferably, the compounded phenolic epoxy resins include phenolic epoxy resin F-44, phenolic epoxy resin F-51 and phenolic epoxy resin F-48 in a mass ratio of (0.8-1.0):(0.4-0.6):(1.5-1.7).
[0012] This invention, by adding three types of phenolic epoxy resins in specific proportions, can react with modified E... Epoxy resin 51 plays a synergistic role in improving the shear strength of the adhesive on the surface of amorphous ribbon at low temperatures. Analysis shows that a specific ratio of phenolic epoxy resin and modified E-51 synergistically enhances low-temperature strength. The structural differences among the three phenolic epoxy resins create a flexible and rigid transition network, which, in conjunction with the flexible segments of end-carboxyl-terminated nitrile rubber, prevents low-temperature embrittlement. Simultaneously, it alleviates interfacial thermal stress, reduces microcrack formation, and ensures load-bearing capacity and interfacial stability at low temperatures.
[0013] Preferably, the preparation method of polyarylamide includes the following steps: melamine and 1,3,5-pyridinetricarboxylic acid chloride are added to a reaction flask, and then pyridine and N-methylpyrrolidone are added in sequence. The mixture is stirred at room temperature to obtain a crude product, which is washed in sequence with anhydrous ethanol, ultrapure water and acetone, then centrifuged, the solid is retained, washed, vacuum dried and cooled to room temperature to obtain polyarylamide.
[0014] Preferably, the mass ratio of melamine to 1,3,5-trimethylbenzene chloride is (0.5-0.65):(1.3-1.5).
[0015] This invention improves the adhesive properties by adding polyarylamide to the system, which can have a synergistic effect with other components.
[0016] Preferably, the curing agent is a latent amine curing agent.
[0017] Preferably, the active diluent is a mixture of TMPTA and TPGDA in a mass ratio of 1:(0.8-1.0).
[0018] The second aspect of this invention provides a method for preparing a gradient-cured polyarylamide amorphous ribbon adhesive, comprising the following steps: placing modified E-51 epoxy resin in a stirring vessel and maintaining the temperature at 60°C; mixing phenolic epoxy resin F-44, phenolic epoxy resin F-51, and phenolic epoxy resin F-48 uniformly to obtain a compounded phenolic epoxy resin; sequentially adding the compounded phenolic epoxy resin and an active diluent to the modified E-51 epoxy resin and stirring; cooling; sequentially adding polyarylamide, a curing agent, a silane coupling agent, an antioxidant, and a heat stabilizer and stirring; placing the mixture in a vacuum degassing chamber for degassing to obtain the gradient-cured polyarylamide amorphous ribbon adhesive.
[0019] The second aspect of the present invention provides the application of gradient-cured polyarylamide amorphous ribbon adhesive in the preparation of polyarylamide-amorphous ribbon composite materials.
[0020] The conditions for gradient curing of the adhesive are as follows: curing temperature is 85℃ / 1.5h + 125℃ / 2.5h + 155℃ / 1h, and the heating rate is controlled at 3℃ / min.
[0021] Compared with the prior art, the advantages and beneficial effects of the present invention are as follows: 1. This invention uses E Modifying epoxy resin with carboxyl-terminated nitrile butadiene rubber (NBR) can improve the shear strength of the adhesive on the surface of amorphous ribbons at room temperature. Furthermore, modifying the NBR with a specific ratio of first, second, and third NBRs can improve its shear strength at high temperatures.
[0022] 2. This invention, by adding three types of phenolic epoxy resin in specific proportions, can react with modified E... 51. Epoxy resin plays a synergistic role, improving the shear strength of the adhesive on the surface of amorphous ribbon at low temperatures. Attached Figure Description
[0023] Figure 1 This is a schematic diagram of bonding an amorphous ribbon to the surface using the adhesive of Example 1.
[0024] Figure 2 This is a schematic diagram of bonding an amorphous ribbon to the surface using the adhesive from Comparative Example 1. Detailed Implementation
[0025] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0026] All raw materials used in the following embodiments of the present invention are commercially available products: The silane coupling agent is silane coupling agent KH550.
[0027] The antioxidant is antioxidant 1010.
[0028] The heat stabilizer is calcium stearate.
[0029] TMPTA, propane trimethylol triacrylate, CAS: 15625-89-5.
[0030] TPGDA, tripropylene glycol diacrylate, CAS: 42978-66-5.
[0031] Irgacure184, CAS No. 947-19-3.
[0032] TPO, CAS No. 75980-60-8.
[0033] Phenolic epoxy resin F-44 and phenolic epoxy resin F-51, Chuzhou Huisheng Electronic Materials Co., Ltd.
[0034] Phenolic epoxy resin F-48, Greenlink (Jining) Chemical Technology Co., Ltd.
[0035] The latent amine curing agent is a mixture of dicyandiamide (DICY) and 2-methylimidazole in a mass ratio of 4:1. Dicyandiamide, CAS: 461-58-5.
[0036] The first-terminal carboxyl-based nitrile butadiene rubber is model CTBN-20, manufactured by Tianyuan Aviation Materials (Yingkou) Technology Co., Ltd.; the carboxyl content of the first-terminal carboxyl-based nitrile butadiene rubber is 0.46-0.60 mol / kg, and the acrylonitrile content is 16.0-22.0%.
[0037] The second-terminal carboxyl-terminated nitrile butadiene rubber is model CTBN-25, manufactured by Tianyuan Aviation Materials (Yingkou) Technology Co., Ltd.; the carboxyl content of the second-terminal carboxyl-terminated nitrile butadiene rubber is 0.51-0.65 mol / kg, and the acrylonitrile content is 22.1-27.0%.
[0038] The third-terminal carboxyl-terminated nitrile butadiene rubber is model CN-10-I, manufactured by Shenzhen Hongyuan Chemical New Material Technology Co., Ltd.; the carboxyl content of the third-terminal carboxyl-terminated nitrile butadiene rubber is 0.58-0.65 mol / kg, and the acrylonitrile content is 8.0-12.0%.
[0039] E 51 epoxy resin, Phoenix E 51. Wanqing (Jiangyin) Chemical Technology Co., Ltd.
[0040] Example 1 This embodiment provides a gradient-curing adhesive for polyarylamide amorphous ribbons, comprising the following components in parts by weight: 3 parts polyarylamide, modified E... The composition includes 60 parts of epoxy resin 51, 7 parts of compounded phenolic epoxy resin, 18 parts of reactive diluent, 1.6 parts of silane coupling agent, 0.7 parts of antioxidant, 0.4 parts of heat stabilizer, and 6 parts of latent amine curing agent. The reactive diluent is a mixture of TMPTA and TPGDA at a mass ratio of 1:0.8. The compounded phenolic epoxy resin includes phenolic epoxy resin F-44, phenolic epoxy resin F-51, and phenolic epoxy resin F-48 at a mass ratio of 0.9:0.5:1.6.
[0041] The modified E The preparation method of 51 epoxy resin includes the following steps: (1) Heat 58 parts by weight of E-51 epoxy resin to 80°C, stir at 200 rpm, and keep warm for 30 min; (2) Under nitrogen protection, add 7 parts by mass of terminal carboxyl butadiene nitrile rubber, raise the temperature to 120°C, increase the stirring speed to 300 rpm, and react at a constant temperature for 2.7 h; the terminal carboxyl butadiene nitrile rubber includes a first terminal carboxyl butadiene nitrile rubber, a second terminal carboxyl butadiene nitrile rubber and a third terminal carboxyl butadiene nitrile rubber in a mass ratio of 1:1.4:0.5.
[0042] (3) After the reaction is complete, the temperature is lowered to 60°C and stirred for 10 minutes to obtain modified E-51 epoxy resin.
[0043] Polyarylamide was prepared according to the method of Example 1 in patent application number 202511661236.4, specifically including the following steps: 0.61 g of melamine and 1.31 g of 1,3,5-pyridinetricarboxylic acid chloride were added to a reaction flask, followed by the sequential addition of 4 mL of pyridine and 40 mL of N-methylpyrrolidone. The mixture was stirred at room temperature for 30 h to obtain a crude product, which was washed sequentially with anhydrous ethanol, ultrapure water and acetone, sonicated for 25 min, and then centrifuged at 8000 r / min for 4 min to separate the solid and liquid phases. The solid was retained and washed twice with each solvent according to the above process. Finally, the product was vacuum dried at 65 °C for 15 h, cooled to room temperature, and ground to a fineness of less than 300 mesh to obtain polyarylamide.
[0044] The preparation method of the gradient-cured polyarylamide amorphous ribbon adhesive includes the following steps: Modified E-51 epoxy resin is placed in a mixing tank and kept at 60°C. Phenolic epoxy resin F-44, phenolic epoxy resin F-51, and phenolic epoxy resin F-48 are mixed evenly to obtain a compound phenolic epoxy resin. The compound phenolic epoxy resin and reactive diluent are added sequentially to the modified E-51 epoxy resin, and the mixture is stirred at 250 rpm for 20 minutes. The temperature is lowered to 40°C, and polyarylamide, latent amine curing agent, silane coupling agent, antioxidant, and heat stabilizer are added sequentially. The mixture is stirred at 200 rpm for 30 minutes. The mixture is then placed in a vacuum degassing chamber and degassed at -0.1 MPa pressure for 15 minutes to obtain the gradient-cured polyarylamide amorphous ribbon adhesive.
[0045] Example 2 The difference between this embodiment and Embodiment 1 is that: a gradient-curing adhesive for amorphous polyarylamide ribbon comprises the following components in parts by weight: 2 parts polyarylamide, modified E... The composition includes 55 parts epoxy resin, 8 parts compounded phenolic epoxy resin, 15 parts reactive diluent, 1 part silane coupling agent, 1 part antioxidant, 0.3 parts heat stabilizer, and 6 parts latent amine curing agent. The reactive diluent comprises a TMPTA / TPGDA compound at a mass ratio of 1:0.8. The compounded phenolic epoxy resin includes phenolic epoxy resins F-44, F-51, and F-48 at a mass ratio of 1.0:0.6:1.5.
[0046] The modified E The preparation method of 51 epoxy resin includes the following steps: (1) Heat 60 parts by weight of E-51 epoxy resin to 80°C, stir at 200 rpm, and keep warm for 30 min; (2) Under nitrogen protection, add 8 parts by mass of terminal carboxyl butadiene nitrile rubber, raise the temperature to 120°C, increase the stirring speed to 300 rpm, and react at a constant temperature for 2.5-3 hours; the terminal carboxyl butadiene nitrile rubber includes a first terminal carboxyl butadiene nitrile rubber, a second terminal carboxyl butadiene nitrile rubber and a third terminal carboxyl butadiene nitrile rubber in a mass ratio of 1:1.3:0.6.
[0047] (3) After the reaction is complete, the temperature is lowered to 60°C and stirred for 10 minutes to obtain modified E-51 epoxy resin.
[0048] The preparation method of the gradient-cured polyarylamide amorphous ribbon adhesive includes the following steps: Modified E-51 epoxy resin is placed in a mixing tank and kept at 60°C. Phenolic epoxy resin F-44, phenolic epoxy resin F-51, and phenolic epoxy resin F-48 are mixed evenly to obtain a compound phenolic epoxy resin. The compound phenolic epoxy resin and reactive diluent are added sequentially to the modified E-51 epoxy resin, and the mixture is stirred at 250 rpm for 20 minutes. The temperature is lowered to 40°C, and polyarylamide, latent amine curing agent, silane coupling agent, antioxidant, and heat stabilizer are added sequentially. The mixture is stirred at 200 rpm for 30 minutes. The mixture is then placed in a vacuum degassing chamber and degassed at -0.1 MPa pressure for 15 minutes to obtain the gradient-cured polyarylamide amorphous ribbon adhesive.
[0049] Comparative Example 1 The difference between this comparative example and Example 1 is that the carboxyl-terminated nitrile butadiene rubber comprises a first-terminated carboxyl-terminated nitrile butadiene rubber, a second-terminated carboxyl-terminated nitrile butadiene rubber, and a third-terminated carboxyl-terminated nitrile butadiene rubber in a mass ratio of 1:1:1. The model is the same as in Example 1.
[0050] Comparative Example 2 The difference between this comparative example and Example 1 is that the end-carboxyl nitrile rubber is a first-end-carboxyl nitrile rubber. The model is the same as in Example 1.
[0051] Comparative Example 3 The difference between this comparative example and Example 1 is that the carboxyl-terminated nitrile butadiene rubber comprises a first carboxyl-terminated nitrile butadiene rubber and a second carboxyl-terminated nitrile butadiene rubber in a mass ratio of 1:1.4. The model is the same as in Example 1.
[0052] Comparative Example 4 The difference between this comparative example and Example 1 is that the compounded phenolic epoxy resin is replaced with phenolic epoxy resin F-51.
[0053] Comparative Example 5 The difference between this comparative example and Example 1 is that the compounded phenolic epoxy resin includes phenolic epoxy resin F-44 and phenolic epoxy resin F-51 in a mass ratio of 0.9:0.5.
[0054] Comparative Example 6 The difference between this comparative example and Example 1 is that the compounded phenolic epoxy resin includes phenolic epoxy resin F-44, phenolic epoxy resin F-51 and phenolic epoxy resin F-48 in a mass ratio of 1:1:1.
[0055] Comparative Example 7 This comparative example is the product prepared according to Example 1 of Chinese Patent CN115181524B, "A Method for Preparing a Silica / Epoxy Resin Inorganic-Organic Hybrid Adhesive".
[0056] Comparative Example 8 This comparative example is a D10 adhesive prepared according to the preparation method of a cashew phenol glycidyl ether modified epoxy resin adhesive in Chinese Patent CN108611036B.
[0057] Performance testing The shear strength of the adhesives in Examples 1-2 and Comparative Examples 1-8 was tested. The bonded test pieces were amorphous ribbon test pieces with an adhesive layer thickness of 0.2 mm. The curing temperature was 85℃ / 1.5h + 125℃ / 2.5h + 155℃ / 1h, and the heating rate was controlled at 3℃ / min, according to GB / T7124. The 2008 standard conducts shear strength tests at 25℃, -150℃, and 120℃.
[0058] The amorphous ribbon after curing the adhesive was subjected to a variable temperature cycling test. The specific cycling process was as follows: the temperature was increased from room temperature (25℃) to 120℃ at a rate of 3℃ / min, held for 1 hour, then decreased to -150℃ at a rate of 3℃ / min, held for 1 hour, and then increased to 25℃ at a rate of 3℃ / min to complete one cycle. This process was repeated until 30 cycles were completed, and then it was observed whether cracking occurred.
[0059] The performance test results are shown in Table 1.
[0060] Table 1 Performance Test Results
[0061] As shown in Table 1, the adhesives of Examples 1-2 maintain excellent adhesion to the surface of amorphous ribbons at room temperature, low temperature and high temperature, and do not crack after 30 thermal cycles.
[0062] In Comparative Example 1, the CTBN blend ratio was 1:1:1, which resulted in an excessively high proportion of low-acrylonitrile CN-10-I and an insufficient proportion of high-acrylonitrile CTBN-20 / 25. This led to an excessively flexible crosslinking network with insufficient rigid support, causing the network to loosen easily at high temperatures and resulting in a decrease in shear strength at 120℃. At the same time, the gradient network structure was destroyed under these conditions, making it unable to effectively buffer the interfacial thermal stress during thermal cycling, ultimately leading to cracking. Although some toughness was retained at low temperatures, insufficient rigidity resulted in a decrease in load-bearing capacity, and the shear strength at -150℃ decreased.
[0063] In Comparative Example 2, a single CTBN-20 was used. Due to the lack of elastic buffer segments of low-acrylonitrile CN-10-I and high-polarity reinforcing segments of CTBN-25, a gradient flexible network could not be formed. Furthermore, at low temperatures, the segment flexibility of single CTBN-20 was insufficient, making it prone to segment freezing, causing the adhesive layer to become brittle and undergo brittle fracture under shear force, resulting in a significant decrease in shear strength at -150℃. At high temperatures, there were not enough elastic segments to absorb thermal stress, and the interfacial polar bonding force between single CTBN-20 and the amorphous ribbon was weaker than that of the composite system, making the interface prone to peeling and reducing the shear strength at 120℃. During temperature cycling, without a gradient network to buffer thermal stress, stress concentrated at the interface, leading to cracking.
[0064] Comparative Example 3 uses a binary blend of CTBN-20 and CTBN-25, lacking low acrylonitrile CN-10-I as an elastic buffer component, which prevents the construction of a complete gradient flexible network. At low temperatures, the adhesive layer becomes brittle due to the lack of flexible segments, and the shear strength at -150°C decreases significantly. During thermal cycling, it cannot effectively absorb the thermal expansion mismatch stress of the amorphous ribbon. After the stress accumulates, it causes interface cracking. At high temperatures, although it retains a certain rigidity due to the high acrylonitrile component, there are no elastic segments to alleviate network relaxation, and the shear strength at 120°C is still lower than that of Example 1.
[0065] In Comparative Example 4, replacing the compounded phenolic epoxy resin with a single F-51 resulted in insufficient rigidity of F-44 at high temperatures and a lack of transition buffering effect of F-48. At high temperatures, F-51 lacked rigidity, the crosslinking network was prone to loosening, and the shear strength at 120℃ dropped significantly. At low temperatures, the absence of F-48 as a transition unit to alleviate the embrittlement tendency of F-51 resulted in insufficient toughness of the adhesive layer and a decrease in shear strength at -150℃. Due to the lack of a gradient transition network, the interfacial thermal stress during thermal cycling could not be buffered, ultimately leading to cracking.
[0066] In Comparative Example 5, the binary compound of F-44 and F-51 lacks F-48 as a flexible-rigid transition unit. There is a performance gap between the high rigidity of F-44 and the high activity of F-51, which cannot form a continuous gradient transition network. At low temperatures, the rigid segments of F-44 are prone to freezing, and the high crosslinking density of F-51 further aggravates embrittlement. The adhesive layer is prone to brittle fracture, and the shear strength at -150°C decreases. During temperature cycling, the performance gap causes stress to concentrate at the crosslinking interface of F-44 / F-51, which cannot be effectively dispersed, eventually leading to cracking. At high temperatures, although F-44 can provide some rigid support, without F-48 to optimize network density, the shear strength at 120°C is still lower than that of Example 1.
[0067] In Comparative Example 6, the phenolic epoxy resin compounding ratio was 1:1:1, resulting in insufficient F-48 and excessive F-51. This weakened the buffering capacity of the gradient transition network, making it unable to effectively alleviate the embrittlement trend of F-44 at low temperatures, resulting in insufficient toughness of the adhesive layer and a decrease in shear strength at -150℃. At high temperatures, the highly active crosslinking network of F-51 was prone to relaxation, and the insufficient F-48 led to poor network density, resulting in a decrease in shear strength at 120℃. During thermal cycling, the transition buffering capacity was insufficient, and the interfacial thermal stress could not be fully dispersed, ultimately leading to cracking.
[0068] Comparative Examples 7 and 8 show that the adhesives of the prior art cannot maintain excellent shear strength at both low and high temperatures simultaneously. Comparative Example 7 exhibits high shear strength at high temperatures but poor performance at low temperatures, while Comparative Example 8 maintains excellent shear strength at low temperatures but exhibits low shear strength at high temperatures.
[0069] pass Figure 1-2 It can be seen that the adhesive of Example 1 is less prone to cracking when bonded to the surface of amorphous ribbon, while the adhesive of Comparative Example 1 is prone to cracking on the surface of amorphous ribbon.
[0070] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. A gradient-curing adhesive for bonding polyarylamide amorphous tapes, characterized in that, The components include the following parts by weight: 1-5 parts of polyarylamide, modified E The mixture comprises 55-65 parts of epoxy resin, 5-8 parts of compounded phenolic epoxy resin, 15-20 parts of reactive diluent, 1-2 parts of silane coupling agent, 0.5-1 part of antioxidant, 0.3-0.5 parts of heat stabilizer, and 3-5 parts of curing agent; the compounded phenolic epoxy resin includes phenolic epoxy resin F-44, phenolic epoxy resin F-51, and phenolic epoxy resin F-48; the modified E 51 epoxy resin is prepared by modifying E-51 epoxy resin with carboxyl-terminated butadiene-acrylonitrile rubber.
2. The gradient-curing adhesive for polyarylamide amorphous ribbons according to claim 1, characterized in that, The modified E The preparation method of 51 epoxy resin includes the following steps: (1) Heat 55-60 parts by weight of E-51 epoxy resin, stir, and keep warm; (2) Under nitrogen protection, add carboxyl-terminated butadiene-acrylonitrile rubber, raise the temperature to 120-125℃, and react at a constant temperature for 2.5-3 hours with stirring; (3) After the reaction is complete, the temperature is lowered to obtain modified E-51 epoxy resin.
3. The gradient-curing adhesive for polyarylamide amorphous ribbons according to claim 2, characterized in that, The carboxyl-terminated nitrile butadiene rubber comprises a first carboxyl-terminated nitrile butadiene rubber, a second carboxyl-terminated nitrile butadiene rubber, and a third carboxyl-terminated nitrile butadiene rubber in a mass ratio of 1:(1.3-1.5):(0.4-0.6).
4. The gradient-curing adhesive for polyarylamide amorphous ribbons according to claim 3, characterized in that, The first-terminal carboxyl-terminated nitrile butadiene rubber has a carboxyl content of 0.46-0.60 mol / kg and an acrylonitrile content of 16.0-22.0%; the second-terminal carboxyl-terminated nitrile butadiene rubber has a carboxyl content of 0.51-0.65 mol / kg and an acrylonitrile content of 22.1-27.0%; and the third-terminal carboxyl-terminated nitrile butadiene rubber has a carboxyl content of 0.58-0.65 mol / kg and an acrylonitrile content of 8.0-12.0%.
5. The gradient-curing adhesive for bonding polyarylamide amorphous ribbons according to claim 1, characterized in that, The compounded phenolic epoxy resins include phenolic epoxy resin F-44, phenolic epoxy resin F-51 and phenolic epoxy resin F-48 with a mass ratio of (0.8-1.0):(0.4-0.6):(1.5-1.7).
6. The gradient-curing adhesive for bonding polyarylamide amorphous ribbons according to claim 1, characterized in that, The preparation method of polyarylamide includes the following steps: melamine and 1,3,5-pyridinetrimethylammonium chloride are added to a reaction flask, and then pyridine and N-methylpyrrolidone are added in sequence. The mixture is stirred at room temperature to obtain a crude product, which is washed in sequence with anhydrous ethanol, ultrapure water and acetone, then centrifuged, the solid is retained, washed, vacuum dried and cooled to room temperature to obtain polyarylamide.
7. The gradient-curing adhesive for bonding polyarylamide amorphous ribbons according to claim 6, characterized in that, The mass ratio of melamine to 1,3,5-trimethylbenzene chloride is (0.5-0.65):(1.3-1.5).
8. The gradient-curing adhesive for bonding polyarylamide amorphous ribbons according to claim 7, characterized in that, The reactive diluent is a mixture of TMPTA and TPGDA in a mass ratio of 1:(0.8-1.0).
9. A method for preparing a gradient-curing, bonding polyarylamide amorphous tape adhesive according to any one of claims 1-8, characterized in that, Includes the following steps: The modified E-51 epoxy resin was placed in a mixing tank, and phenolic epoxy resin F-44, phenolic epoxy resin F-51 and phenolic epoxy resin F-48 were mixed evenly to obtain a compound phenolic epoxy resin. The compound phenolic epoxy resin and reactive diluent were added to the modified E-51 epoxy resin in sequence and stirred. After cooling, polyarylamide, curing agent, silane coupling agent, antioxidant and heat stabilizer were added in sequence and stirred. The mixture was placed in a vacuum degassing box for degassing to obtain a gradient-cured polyarylamide amorphous ribbon adhesive.
10. The application of a gradient-curing adhesive for polyarylamide amorphous ribbon according to any one of claims 1-8 in the preparation of polyarylamide-amorphous ribbon composite materials.