Anisotropic conductive film containing cations and peroxide free radicals and preparation method thereof

Abstract

The invention is suitable for the technical field of electronic materials, and provides an anisotropic conductive film containing cations and peroxide free radicals and a preparation method thereof. The anisotropic conductive film comprises the following components in percentage by weight: 30%-60% of cationic polymer resin, 15%-35% of free radical polymer resin, 1%-5% of a thermally activated cationic initiator, 2%-8% of a peroxide free radical initiator, 5%-15% of conductive particles and 5%-15% of a functional additive, according to the invention, the epoxy resin curing reaction initiated by the cationic initiator and the free radical polymerization reaction initiated by the peroxide or the photoinitiator are synchronously carried out, the advantages of two curing mechanisms are complemented, and high mechanical strength, electrical stability and thermal durability which are difficult to achieve by a single curing system are realized.

Description

Technical Field

[0001] This invention relates to the field of electronic materials technology, specifically to anisotropic conductive films containing cations and peroxide free radicals and their preparation methods. Background Technology

[0002] ACF (Automatic Conductor Coherence) requires electrical connections between tiny electrodes while maintaining insulation in other directions, and demands properties such as adhesion, heat resistance, and stable connection resistance. In recent years, with the increasing emphasis on reliability assessment, the demand for high reliability performance has been growing.

[0003] Existing acrylic fiber reinforced plastics (ACFs) typically employ resins with a single curing mechanism, such as thermosetting epoxy resins or peroxide-induced radical-cured acrylic resins. ACFs based on thermosetting epoxy resins exhibit high glass transition temperature (Tg) and mechanical strength (modulus) after curing, maintaining excellent heat resistance and reliability in high-temperature and high-humidity environments. However, their curing speed is relatively slow, and their high rigidity makes them susceptible to peeling or cracking upon external impact or slight bending of the substrate, especially noticeable in flexible thin glass substrate applications. Peroxide-induced radical-cured acrylic resins, on the other hand, can cure rapidly at lower temperatures and can be mixed with thermoplastic resins to improve impact cushioning and reduce thermal stress. However, their Tg and modulus adjustment are limited, their heat resistance in high-temperature environments is poor, and the free radical reaction is sensitive to oxygen, making it difficult to guarantee curing stability.

[0004] Therefore, in view of the above situation, there is an urgent need to provide anisotropic conductive films containing cations and peroxide free radicals and their preparation methods to overcome the shortcomings in current practical applications. Summary of the Invention

[0005] The purpose of this invention is to provide anisotropic conductive films containing cations and peroxide free radicals and their preparation methods, effectively solving the problems in the background art.

[0006] This invention is achieved by using an anisotropic conductive film containing cations and peroxide free radicals, comprising the following components by weight percentage: Cationic polymer resin 30%~60%, free radical polymer resin 15%~35%, thermally activated cationic initiator 1%~5%, peroxide free radical initiator 2%~8%, conductive particles 5%~15%, functional additives 5%~15%; The cationic polymer resin is a cationic polymer monomer or oligomer activated by ultraviolet light or heat. The free radical polymerizing resin is a monomer containing acrylate or methacrylate and oligomers that can undergo polymerization induced by a free radical initiator.

[0007] As a further aspect of the present invention: the cationic polymeric resin includes oxacyclopropane monomers or oligomers, vinyl ether monomers, and functional epoxy resins.

[0008] As a further aspect of the present invention: the oxacyclopropane monomer or oligomer is 3-ethyl-3-oxacyclopropane-methanol; The functional epoxy resin is BPA type, BPF type, DCPD type or multifunctional high viscosity epoxy resin.

[0009] As a further aspect of the present invention: the free radical polymeric resin comprises low-viscosity monomers, oligomers, and composite copolymers; The low-viscosity monomer is TPGDA or HDDA; The oligomer is a polyurethane acrylate or an epoxy acrylate.

[0010] As a further aspect of the present invention: the cationic initiator includes at least one of thermally activated diaryliodonium salt, triarylsulfonium salt, and sulfonium salt.

[0011] As a further aspect of the present invention: the peroxide radical initiator includes benzoyl peroxide (BPO), lauroyl peroxide (LPO), di-tert-butyl peroxide (DTBPO), azobisisobutyronitrile (AIBN), and Luperox series peroxides.

[0012] As a further aspect of the present invention: the conductive particles are metal-coated polymer spherical particles or metal spherical particles, the coating material of the metal-coated polymer spherical particles is nickel, silver or gold, and the diameter of the conductive particles is 1~20μm.

[0013] As a further aspect of the present invention: the functional additives include shrinkage inhibitors, heat stabilizers, dispersants, and viscosity-adjusting fillers; The dispersant is a surfactant and nano-silicone.

[0014] The present invention also provides a method for preparing the thermally activated dual-curing anisotropic conductive film as described above, the method comprising the following steps: Step 1, Raw material pretreatment: Place the cationic polymer resin and the free radical polymer resin in a vacuum drying oven and dry them for 2 to 4 hours at 60~80℃ and vacuum degree ≤-0.09MPa to remove moisture and volatile impurities from the raw materials; The solid components in the functional additives are pulverized to a particle size ≤5μm to ensure uniform dispersion; Step 2, Resin matrix preparation: Weigh the pretreated cationic polymer resin, free radical polymer resin, thermally activated cationic initiator, peroxide free radical initiator and functional additives by weight percentage, place them in a temperature-controlled high-speed mixer, and simultaneously introduce nitrogen gas for protection to obtain a bubble-free, homogeneous and stable resin matrix mixture. Step 3, Dispersion of conductive particles: Add the predetermined weight percentage of conductive particles to the resin matrix mixture obtained in Step 2, transfer it to a vacuum disperser, and premix it at low speed for 10 to 15 minutes at 25 to 30°C and 100 to 200 r / min to initially disperse the conductive particles. Then the ultrasonic dispersion module is turned on, and the mixture is stirred intermittently during the ultrasonic process while maintaining a vacuum of ≤-0.08MPa to remove air bubbles generated during dispersion. After ultrasonication, continue stirring at low speed for 5-10 minutes to ensure that the conductive particles are evenly dispersed and do not agglomerate, thus obtaining the ACF premix. Step 4, Coating and Molding: Transfer the ACF premix obtained in Step 3 to the material tank of the coating equipment, and coat it onto the corona-treated release film using a doctor blade coating or slot coating method. During the coating process, the coating temperature is controlled at 25~35℃ and the coating speed is 0.5~2.0m / min. The coating thickness is adjusted to 5~50μm by adjusting the coating gap. After coating, the coating is pre-dried using an infrared drying channel at a temperature of 40~60℃ and a drying time of 1~3 minutes to remove residual bubbles and trace volatile components. Step 5, thermosetting treatment: The pre-dried film material is sent into a continuous thermosetting oven and a segmented heating and curing process is adopted: the first stage is heated to 60~90℃ and held for 2~3 seconds to start the initial decomposition of peroxide free radical initiator; The second stage involves heating to 120~180℃ and holding for 3~7 seconds to activate the cationic initiator and complete the dual curing reaction. Maintain a nitrogen atmosphere inside the furnace during the curing process; Step 6, Post-processing and winding: The cured film is cooled to room temperature by cooling rollers, and then quality is inspected by an online detection device to remove unqualified products; After the qualified film material is trimmed, it is wound up in a clean environment with the winding tension controlled at 5~15N. The winding speed is synchronized with the conveying speed of the curing oven to obtain the finished product of heat-activated double-cured anisotropic conductive film.

[0015] As a further aspect of the present invention: In step 5, during the segmented heating and curing process, the peroxide free radical initiator begins to decompose and generate free radicals in the first low-temperature stage, which triggers the rapid polymerization of the free radical polymer resin to form a preliminary cross-linked polymer network, thereby achieving rapid shaping of the membrane material. In the second high-temperature stage, the thermally activated cationic initiator is fully activated, initiating a stepwise polymerization reaction of the cationic polymer resin. It interpenetrates and synergistically crosslinks with the previously formed free radical polymer network, ultimately forming a dense and uniform three-dimensional interpenetrating network structure.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. Contact resistance stability is significantly improved (initially 0.3Ω, after testing 0.45Ω). 2. High heat resistance (Tg>120℃); 3. Excellent fatigue resistance of the connection parts, adapting to differences in thermal expansion coefficients; 4. The oxygen sensitivity of the peroxide free radical reaction is compensated by the cationic reaction, which improves the curing stability. Detailed Implementation

[0017] The technical solution of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, 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.

[0018] The present invention will be further explained below with reference to specific embodiments.

[0019] The anisotropic conductive film containing cations and peroxide free radicals provided in this embodiment of the invention comprises the following components by weight percentage: Cationic polymer resin 30%~60%, free radical polymer resin 15%~35%, thermally activated cationic initiator 1%~5%, peroxide free radical initiator 2%~8%, conductive particles 5%~15%, functional additives 5%~15%; In this embodiment, the cationic polymer resin can be cured by ultraviolet (UV) or heat-activated cationic polymer monomers or oligomers to form a dense three-dimensional network structure, which determines the mechanical strength, electrical insulation, and heat resistance. Typical cationic polymer resins include: Oxycyclopropane monomers or oligomers, such as 3-ethyl-3-oxycyclopropane-methanol; Vinyl ether monomers; Functional epoxy resins (BPA type, BPF type, DCPD type, multifunctional high viscosity epoxy resin, etc.); Free radical polymerized resins, induced by free radical initiators, contain acrylate or methacrylate monomers and oligomers, cure rapidly, and impart transparency and elasticity to the film. Includes: Low viscosity monomers such as TPGDA and HDDA; Oligomers such as polyurethane acrylates and epoxy acrylates; Composite copolymers are used to adjust properties; Cationic initiators initiate cationic polymerization reactions through UV or thermal activation, mainly including: Diaryliodonium salt; Triarylsulfonium salt; Sulfonium salt; Free radical initiators (peroxide-based): Initiators that generate free radicals through thermal decomposition, typically including: Benzoyl peroxide (BPO); Lauroyl peroxide (LPO); Di-tert-butyl peroxide (DTBPO); AIBN and Luperox series; Conductive particles impart perpendicular conductivity to ACF, commonly used as follows: Metal-coated polymer spherical particles (nickel, silver, gold coating); Metallic spherical particles, approximately 1~20μm in diameter; Functional additives include shrinkage inhibitors, heat stabilizers, dispersants (surfactants, nano-silicone), viscosity modifiers, and fillers to improve performance and processability. Peroxide radical initiators decompose upon heating, rapidly generating free radicals that promote the free radical polymerization of acrylates; cationic initiators are activated upon heating, initiating the cationic polymerization of oxacyclopropane and vinyl ethers. Free radical curing is performed first to rapidly form a polymer network, followed by cationic curing to further enhance structural strength and achieve high mechanical strength and heat resistance.

[0020] This invention also provides a method for preparing the thermally activated dual-curing anisotropic conductive film as described above, characterized in that the method includes the following steps: Step 1, Raw material pretreatment: Place the cationic polymer resin and the free radical polymer resin in a vacuum drying oven and dry them for 2 to 4 hours at 60~80℃ and vacuum degree ≤-0.09MPa to remove moisture and volatile impurities from the raw materials; The solid components in the functional additives are pulverized to a particle size ≤5μm to ensure uniform dispersion; Step 2, Resin matrix preparation: Weigh the pretreated cationic polymer resin, free radical polymer resin, thermally activated cationic initiator, peroxide free radical initiator and functional additives according to the weight percentage of any one of claims 1 to 8, place them in a temperature-controlled high-speed mixer, set the mixing temperature to 25 to 40°C, the stirring speed to 300 to 500 r / min, and the stirring time to 20 to 40 minutes, while simultaneously introducing nitrogen gas for protection (nitrogen flow rate of 0.5 to 1.0 L / min) to prevent premature decomposition of the free radical initiator and oxidation of the resin, and obtain a bubble-free, homogeneous and stable resin matrix mixture; Step 3, Dispersion of conductive particles: Add the predetermined weight percentage of conductive particles to the resin matrix mixture obtained in Step 2, transfer it to a vacuum disperser, and premix it at low speed for 10 to 15 minutes at 25 to 30°C and 100 to 200 r / min to initially disperse the conductive particles. Then, turn on the ultrasonic dispersion module, set the ultrasonic power to 100~300W, the ultrasonic frequency to 20~40kHz, and the ultrasonic time to 5~10 minutes. During the ultrasonic process, stir intermittently (stir for 30 seconds every 2 minutes of ultrasonication, with a stirring speed of 80~120r / min), while maintaining a vacuum degree of ≤-0.08MPa to remove bubbles generated during the dispersion process. After ultrasonication, continue stirring at low speed for 5-10 minutes to ensure that the conductive particles are evenly dispersed and do not agglomerate, thus obtaining the ACF premix. Step 4, Coating and Molding: Transfer the ACF premix obtained in Step 3 to the material tank of the coating equipment, and coat it onto the release film that has been corona treated (surface tension ≥38mN / m) using a doctor blade coating or slit coating method. During the coating process, the coating temperature is controlled at 25~35℃ and the coating speed is 0.5~2.0m / min. The coating thickness is adjusted to 5~50μm by adjusting the coating gap. After coating, the coating is pre-dried using an infrared drying channel at a temperature of 40~60℃ and a drying time of 1~3 minutes to remove residual bubbles and trace volatile components. Step 5, thermosetting treatment: The pre-dried film material is sent into a continuous thermosetting oven and a segmented heating and curing process is adopted: the first stage is heated to 60~90℃ and held for 2~3 seconds to start the initial decomposition of peroxide free radical initiator; The second stage involves heating to 120~180℃ and holding for 3~7 seconds to activate the cationic initiator and complete the dual curing reaction. Maintain a nitrogen atmosphere (oxygen content ≤0.5%) inside the furnace during the curing process to avoid oxygen inhibition of polymerization. In the segmented heating and curing process, the peroxide free radical initiator begins to decompose and generate free radicals in the first low-temperature stage (60~90℃), which triggers the rapid polymerization of the free radical polymer resin to form a preliminary cross-linked polymer network, thereby achieving rapid shaping of the membrane material. In the second high-temperature stage (120~180℃), the thermally activated cationic initiator is fully activated, initiating the cationic polymer resin to undergo a stepwise polymerization reaction. It interpenetrates and synergistically crosslinks with the free radical polymer network formed in the previous stage, ultimately forming a dense and uniform three-dimensional interpenetrating network structure. The total curing time of the dual curing reaction is 5 to 10 seconds, ensuring a balance between production efficiency and complete curing. Step 6, Post-processing and winding: The cured film is cooled to room temperature by cooling rollers (cooling roller temperature is 15~25℃), and then quality inspection is carried out by online inspection devices (including thickness detector and appearance defect detector) to remove unqualified products; After the qualified membrane material is trimmed, it is wound up in a clean environment (Class 1000). The winding tension is controlled at 5~15N, and the winding speed is synchronized with the conveying speed of the curing oven to obtain the finished product of heat-activated double-cured anisotropic conductive film.

[0021] In this embodiment, the present invention enhances performance through a dual curing mechanism. The epoxy resin curing reaction initiated by a cationic initiator is carried out simultaneously with the free radical polymerization reaction initiated by a peroxide or photoinitiator, complementing the advantages of both curing mechanisms to achieve high mechanical strength, electrical stability, and thermal durability that are difficult to achieve with a single curing system. It is particularly suitable for high-temperature and high-voltage environments, maintaining reliable electrical connection performance. The present invention achieves high-reliability ACF and adapts to high-density packaging processes. The ACF of the present invention maintains vertical conductivity and horizontal insulation, reducing problems such as the movement and aggregation of conductive particles and uneven curing under fine spacing. It is suitable for ultra-high-density electronic packaging such as flexible printed circuit boards (FPCBs), glass film (FOG), chip film encapsulation (COF), chip glass encapsulation (COG), and epitaxial wire bonding (OLB), and is widely used in advanced electronic devices such as mobile devices, display modules, and high-resolution image sensors.

[0022] Example 1 Anisotropic conductive film containing cationic and peroxide free radicals has the following components and weight percentages: multifunctional epoxy oligomer (BPA type) 40%, trioxane monomer (3-ethyl-3-oxacyclopropane methanol) 10%, tripropylene glycol diacrylate (TPGDA) 20%, polyurethane acrylate 10%, benzoyl peroxide (BPO) 3%, diaryl iodine salt 2%, nickel-coated polymer spherical conductive particles (5μm in diameter) 10%, and functional additives (nano-silica gel dispersant, shrinkage inhibitor, inorganic nano viscosity modifier filler) 5%.

[0023] The method for preparing the above-mentioned anisotropic conductive film containing cations and peroxide free radicals includes the following steps: (1) Raw material pretreatment: The multifunctional epoxy oligomer, trioxane monomer, TPGDA and polyurethane acrylate were placed in a vacuum drying oven and dried for 3 hours at 70℃ and vacuum degree -0.095MPa; the inorganic nano viscosity modifier filler in the functional additive was crushed to a particle size ≤3μm. (2) Resin matrix preparation: Weigh each pretreated resin component, BPA, diaryliodomonium salt and functional additives according to the above weight percentages, place them in a temperature-controlled high-speed mixer, set the mixing temperature to 30℃, the stirring speed to 400r / min and the stirring time to 30 minutes, and simultaneously introduce nitrogen gas (flow rate 0.8L / min) to obtain a bubble-free, homogeneous and stable resin matrix mixture; (3) Dispersion of conductive particles: Nickel-coated polymer spherical conductive particles were added to the resin matrix mixture and transferred to a vacuum disperser. The mixture was premixed at low speed for 12 minutes at 28°C and 150 r / min. Then the ultrasonic dispersion module was turned on and the ultrasonic power was set to 200 W, ultrasonic frequency to 20 kHz, and ultrasonic time to 8 minutes. Stirring was performed for 30 seconds every 2 minutes of ultrasonication (stirring speed 100 r / min) while maintaining a vacuum of -0.085 MPa. After ultrasonication, low-speed stirring was continued for 8 minutes to obtain the ACF premix. (4) Coating and molding: Transfer the ACF premix to the material tank of the coating equipment and coat it onto the release film that has been corona treated (surface tension 40mN / m) by scraper coating; the coating temperature is 30℃, the coating speed is 1.0m / min, and the coating thickness is 20μm; after coating, pre-dry it in the infrared drying channel at 50℃ for 2 minutes. (5) Thermal curing treatment: The pre-dried film material is sent into a continuous thermal curing oven and cured in stages: the first stage is heated to 75°C and held for 2.5 seconds; the second stage is heated to 150°C and held for 2.5 seconds, with a total curing time of 5 seconds; the oven is filled with nitrogen atmosphere and the oxygen content is ≤0.3%; (6) Post-processing and winding: The cured film is cooled to room temperature by a cooling roller (temperature 20℃), and quality is inspected by an online thickness detector (accuracy ±0.1μm) and an appearance defect detector; after the qualified film is trimmed, it is wound in a Class 1000 clean environment with a winding tension of 10N and the winding speed is synchronized with the conveying speed of the curing oven to obtain the finished product.

[0024] Performance testing: The ACF product prepared in Example 1 above was subjected to performance testing. The test conditions and results are as follows: Hot pressing conditions: 150℃, 5 seconds, 3MPa Hot-pressed substrate: 1.0T ITO glass, gold-plated FPC HAST accelerated aging test: 110℃, 85%RH, 2atm, 96 hours Test results: Peel strength: 1000 gf / cm (90° peel) Contact resistance change: decrease within 50% There are no bubbles or peeling.

[0025] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An anisotropic conductive film containing cations and peroxide free radicals, characterized in that, Includes the following components by weight percentage: Cationic polymer resin 30%~60%, free radical polymer resin 15%~35%, thermally activated cationic initiator 1%~5%, peroxide free radical initiator 2%~8%, conductive particles 5%~15%, functional additives 5%~15%; The cationic polymer resin is a cationic polymer monomer or oligomer activated by ultraviolet light or heat. The free radical polymerizing resin is a monomer containing acrylate or methacrylate and oligomers that can undergo polymerization induced by a free radical initiator.

2. The anisotropic conductive film containing cations and peroxide free radicals according to claim 1, characterized in that, The cationic polymeric resin includes oxacyclopropane monomers or oligomers, vinyl ether monomers, and functional epoxy resins.

3. The anisotropic conductive film containing cations and peroxide free radicals according to claim 2, characterized in that, The oxetine monomer or oligomer is 3-ethyl-3-oxetine methanol; The functional epoxy resin is BPA type, BPF type, DCPD type or multifunctional high viscosity epoxy resin.

4. The anisotropic conductive film containing cations and peroxide free radicals according to claim 1, characterized in that, The free radical polymeric resin includes low-viscosity monomers, oligomers, and composite copolymers; The low-viscosity monomer is TPGDA or HDDA; The oligomer is a polyurethane acrylate or an epoxy acrylate.

5. The anisotropic conductive film containing cations and peroxide free radicals according to claim 1, characterized in that, The cationic initiator includes at least one of thermally activated diaryliodonium salt, triarylsulfonium salt, and sulfonium salt.

6. The anisotropic conductive film containing cations and peroxide free radicals according to claim 1, characterized in that, The peroxide radical initiators include benzoyl peroxide (BPO), lauroyl peroxide (LPO), di-tert-butyl peroxide (DTBPO), azobisisobutyronitrile (AIBN), and Luperox series peroxides.

7. The anisotropic conductive film containing cations and peroxide free radicals according to claim 1, characterized in that, The conductive particles are metal-coated polymer spherical particles or metal spherical particles, the coating material of the metal-coated polymer spherical particles is nickel, silver or gold, and the diameter of the conductive particles is 1~20μm.

8. The anisotropic conductive film containing cations and peroxide free radicals according to claim 1, characterized in that, The functional additives include shrinkage inhibitors, heat stabilizers, dispersants, and viscosity modifiers. The dispersant is a surfactant and nano-silicone.

9. The method for preparing a thermally activated dual-curing anisotropic conductive film according to any one of claims 1-8, characterized in that, The method includes the following steps: Step 1, Raw material pretreatment: Place the cationic polymer resin and the free radical polymer resin in a vacuum drying oven and dry them for 2 to 4 hours at 60~80℃ and vacuum degree ≤-0.09MPa to remove moisture and volatile impurities from the raw materials; The solid components in the functional additives are pulverized to a particle size ≤5μm to ensure uniform dispersion; Step 2, Resin matrix preparation: Weigh the pretreated cationic polymer resin, free radical polymer resin, thermally activated cationic initiator, peroxide free radical initiator and functional additives by weight percentage, place them in a temperature-controlled high-speed mixer, and simultaneously introduce nitrogen gas for protection to obtain a bubble-free, homogeneous and stable resin matrix mixture. Step 3, Dispersion of conductive particles: Add the predetermined weight percentage of conductive particles to the resin matrix mixture obtained in Step 2, transfer it to a vacuum disperser, and premix it at low speed for 10 to 15 minutes at 25 to 30°C and 100 to 200 r / min to initially disperse the conductive particles. Then the ultrasonic dispersion module is turned on, and the mixture is stirred intermittently during the ultrasonic process while maintaining a vacuum of ≤-0.08MPa to remove air bubbles generated during dispersion. After ultrasonication, continue stirring at low speed for 5-10 minutes to ensure that the conductive particles are evenly dispersed and do not agglomerate, thus obtaining the ACF premix. Step 4, Coating and Molding: Transfer the ACF premix obtained in Step 3 to the material tank of the coating equipment, and coat it onto the corona-treated release film using a doctor blade coating or slot coating method. During the coating process, the coating temperature is controlled at 25~35℃ and the coating speed is 0.5~2.0m / min. The coating thickness is adjusted to 5~50μm by adjusting the coating gap. After coating, the coating is pre-dried using an infrared drying channel at a temperature of 40~60℃ and a drying time of 1~3 minutes to remove residual bubbles and trace volatile components. Step 5, thermosetting treatment: The pre-dried film material is sent into a continuous thermosetting oven and a segmented heating and curing process is adopted: the first stage is heated to 60~90℃ and held for 2~3 seconds to start the initial decomposition of peroxide free radical initiator; The second stage involves heating to 120~180℃ and holding for 3~7 seconds to activate the cationic initiator and complete the dual curing reaction. Maintain a nitrogen atmosphere inside the furnace during the curing process; Step 6, Post-processing and winding: The cured film is cooled to room temperature by cooling rollers, and then quality is inspected by an online detection device to remove unqualified products; After the qualified film material is trimmed, it is wound up in a clean environment with the winding tension controlled at 5~15N. The winding speed is synchronized with the conveying speed of the curing oven to obtain the finished product of heat-activated double-cured anisotropic conductive film.

10. The preparation method according to claim 9, characterized in that, In step 5, during the segmented heating and curing process, the peroxide free radical initiator begins to decompose and generate free radicals in the first low-temperature stage, which triggers the rapid polymerization of the free radical polymer resin to form a preliminary cross-linked polymer network, thereby achieving rapid shaping of the membrane material. In the second high-temperature stage, the thermally activated cationic initiator is fully activated, initiating a stepwise polymerization reaction of the cationic polymer resin. It interpenetrates and synergistically crosslinks with the previously formed free radical polymer network, ultimately forming a dense and uniform three-dimensional interpenetrating network structure.