Special film with high adhesive force and preparation method thereof

Abstract

The invention relates to the field of special films, in particular to a high-adhesion special film and a preparation method thereof, and the special film comprises a polymer base film, a bonding layer arranged on at least one side of the polymer base film and a metal layer arranged on the bonding layer. According to the special film, the bonding layer is arranged between the base film and the metal layer, the performance of adhesive force is enhanced, excellent dielectric performance and good temperature resistance are kept, and the prepared special film is suitable for high-performance composite current collectors and thin-film capacitors and has important industrial application value and wide market prospects.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of special films, in particular to a special film with high adhesion and a preparation method thereof. BACKGROUND

[0002] With the rapid development of modern electronic devices, electric vehicles, aerospace and energy storage technology, the demand for high-performance special thin film materials is increasing. Among the many special films, composite current collector films and capacitor films as two key materials play a decisive role in the performance of electronic devices and energy storage systems.

[0003] Composite current collector films are mainly used in electrochemical devices such as lithium ion batteries, as the current collector of the positive and negative electrodes, playing a role in collecting current and conducting energy. Traditional current collectors mostly use metal foils (such as copper foil, aluminum foil), but have the disadvantages of heavy weight, easy corrosion, and high safety risk in the case of battery thermal runaway. In recent years, composite current collectors adopt a sandwich structure of "polymer substrate + metal plating layer", which can not only reduce weight, but also improve the safety performance and cycle life of the battery through the insulation and flexibility of the polymer material. However, the core challenge of this structure is how to achieve a firm bond between the metal layer and the polymer base film to avoid the decline in conductivity caused by interface peeling. Capacitor films, especially polymer film capacitors, play an important role in the global industrial capacitor market due to their high dielectric strength, low energy loss, and good self-healing properties. They are widely used in power electronic systems, new energy vehicle drive systems, pulse power systems and other fields. With the continuous increase in power of electronic devices and power equipment, and the continuous pursuit of small size and compact power modules, capacitor films need to work stably at higher temperatures and stronger electric fields, which puts high requirements on the dielectric properties, heat resistance of the film, and the bonding force between the electrode and the dielectric layer.

[0004] In summary, the physical bonding force between the polymer base film and the metal layer in the composite current collector is limited, and interface peeling easily occurs under long-term use or extreme conditions, leading to increased resistance or even functional failure. Traditional polymer capacitor films have a sharp decline in dielectric properties at high temperatures, a significant increase in leakage current, and a significant reduction in efficiency, which cannot meet the demand of high-temperature application scenarios. Therefore, the existing technology cannot simultaneously achieve high adhesion, excellent dielectric properties, and good temperature resistance, and a new type of special film needs to be developed to meet the above requirements. SUMMARY

[0005] In view of the problems in the prior art, the purpose of the present application is to provide a special film with high adhesion and a preparation method thereof.

[0006] The purpose of the present application is achieved by adopting the following technical solutions: In a first aspect, the present invention provides a special film with high adhesion, comprising a polymer base film, an adhesive layer disposed on at least one side of the polymer base film, and a metal layer disposed on the adhesive layer.

[0007] Preferably, the special membrane comprises, from top to bottom, a first metal layer, a first adhesive layer, a polymer base film layer, a second adhesive layer, and a second metal layer.

[0008] Preferably, the polymer base film layer is made of one of polyethylene terephthalate (PET), polypropylene (PP), polyimide (PI), and polyethylene naphthalate (PEN).

[0009] Preferably, the thickness of the polymer-based film layer is 2-20 μm.

[0010] Preferably, the metal layer is copper, aluminum, or silver, and has a thickness of 20-500 nm.

[0011] Preferably, the thickness of the adhesive layer is 1-2 μm, and the components of the adhesive layer, calculated by weight, include: 80-120 parts polyether modified epoxy resin, 5-25 parts nano-reinforcing filler, 0.5-3 parts silane coupling agent, 0.1-0.5 parts defoamer, 10-30 parts curing agent and 200-400 parts solvent.

[0012] Preferably, the polyether-modified epoxy resin is at least one of Adico EP-4000, Cellway HQ-5000, and Adico EP-1307.

[0013] Preferably, the silane coupling agent is an aminosilane coupling agent, including at least one of γ-aminopropyltriethoxysilane, γ-aminopropylmethyldiethoxysilane, N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane, and N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane.

[0014] Preferably, the defoamer is at least one of BYK-A525, BYK-065, and DS8750.

[0015] Preferably, the curing agent is an amine curing agent, including at least one of Wanhua TSG-7190, Momentive 8140, and Huntsman D-230.

[0016] Preferably, the solvent is at least one selected from toluene, xylene, isopropanol, ethylene glycol methyl ether, N-methylpyrrolidone, and N,N-dimethylformamide.

[0017] Preferably, the preparation method of the nano-reinforced filler includes: S1. Preparation of anhydride-terminated polyimide: Under nitrogen protection, p-phenylenediamine was weighed and added to N,N-dimethylformamide. After thorough mixing at room temperature, 3,3',4,4'-biphenyltetracarboxylic dianhydride was added. The temperature was raised to 35-45℃ and stirred for 8-12 hours to obtain an anhydride-terminated polyimide precursor solution. S2. Preparation of amino-framework two-dimensional nanomaterials: Weigh out water and N,N-dimethylformamide and mix them. Add scandium acetate (Sc(OAc)3) and yttrium acetate (Y(OAc)3) and dissolve them completely. Then add 2,3,6,7,10,11-hexaaminotriphenyl (HATP) and sonicate at room temperature for 1-2 hours. Then transfer the mixed solution to a reaction vessel and solvothermal react at 80-100℃ for 10-20 hours. After the reaction is completed, cool naturally and wash three times with acetone and water by centrifugation. Dry under vacuum to obtain amino framework two-dimensional nanomaterials. S3. Preparation of nano-reinforced fillers: Under nitrogen protection, amino framework two-dimensional nanomaterials were added to an anhydride-terminated polyimide precursor solution. After thorough mixing at room temperature, the mixture was heated to 30-40℃ and stirred for 6-10 hours. Then, acetic anhydride as a dehydrating agent and triethylamine as a catalyst were added, and the mixture was heated to 100-120℃ and stirred for 6-10 hours. The solvent was removed by vacuum distillation, and the mixture was washed three times with ethanol and dried under vacuum to obtain the nano-reinforced filler.

[0018] Preferably, in S1, the ratio of p-phenylenediamine, 3,3',4,4'-biphenyltetracarboxylic dianhydride and N,N-dimethylformamide is 10.8 g:(29.7-30.1) g:(100-200) mL.

[0019] Preferably, in S2, the ratio of scandium acetate, yttrium acetate, 2,3,6,7,10,11-hexaaminotriphenyl, water and N,N-dimethylformamide is (6.7-15.5)g:(8.1-18.6)g:(31.8-33.4)g:(50-150)mL:(100-200)mL.

[0020] Preferably, in step S3, the ratio of the amino-framework two-dimensional nanomaterial and the anhydride-terminated polyimide precursor solution is (2.5-8.5) g: 100 mL.

[0021] Preferably, in S3, the dehydrating agent is acetic anhydride, the catalyst is triethylamine, and the ratio of the dehydrating agent, the catalyst, and the anhydride-terminated polyimide precursor solution is (5-15)g:(2-8)g:100mL.

[0022] Secondly, the present invention provides a method for preparing a special film with high adhesion, comprising the following steps: Step 1, Prepare the adhesive coating solution: Weigh each component of the adhesive layer according to the weight proportions, place them in a high-speed disperser, disperse until a uniform suspension is formed, and filter through a filter screen; Step 2, Coating and curing the adhesive layer: Apply the adhesive coating liquid to the surface of the base film, and then place the coated film in an oven for curing treatment to complete the initial cross-linking and shaping of the adhesive layer; Step 3, Deposit metal layer: The film material after the adhesive layer has been cured is sent into the magnetron sputtering vacuum chamber, and a metal target is sputtered onto the adhesive layer of the film material to achieve the required thickness. Step 4, Post-processing: The film with the deposited metal layer is cured in a curing chamber and then wound up to complete the preparation.

[0023] The beneficial effects of this invention are as follows: 1. This invention enhances adhesion by setting an adhesive layer between the base film and the metal layer, while maintaining excellent dielectric properties and good temperature resistance. The resulting special film is suitable for high-performance composite current collectors and thin-film capacitors, and has significant industrial application value and broad market prospects.

[0024] 2. The adhesive layer of this invention uses polyether-modified epoxy resin as the main material and nano-reinforcing filler as the reinforcing agent, thereby improving the overall performance of the membrane material. The nano-reinforcing filler is a core-shell coated filler prepared by reacting and combining an amino-containing scandium-yttrium composite nanoframework material with an anhydride-terminated polyimide. Compared to traditional polyimide materials, the nano-reinforcing filler prepared in this invention exhibits better compatibility in the system and demonstrates superior enhancement performance in improving the system's strength, adhesion, and other properties. Furthermore, testing revealed that the unique ratio of scandium and yttrium used in the nano-reinforcing filler results in better performance than using a single metal.

[0025] 3. The polyimide segments in the nano-reinforced filler form a strong bond with the two-dimensional MOF nanosheets through amide bonds. Simultaneously, the various polar functional groups on the filler surface can form coordination bonds with the metal layer, establishing a stable chemical bond between the base film, adhesive layer, and metal layer. This also helps to form a uniform electric field distribution, avoiding early breakdown caused by localized electric field concentration. Furthermore, the various crosslinking points on the filler surface can form a dense three-dimensional network structure with the epoxy resin, effectively suppressing the movement of polymer segments at high temperatures.

[0026] 4. This invention exhibits excellent process adaptability, with the adhesive layer demonstrating superior stability. It is fully compatible with existing coating-sputtering production processes and suitable for large-scale continuous production. The special membrane material of this invention demonstrates outstanding performance in terms of flexibility, high-temperature resistance, and long-term reliability, ensuring stable product performance in various application environments. Detailed Implementation

[0027] To better understand the above technical solutions, exemplary embodiments of the present invention are described in more detail below. While exemplary embodiments of the present invention are shown, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present invention and to fully convey the scope of the invention to those skilled in the art.

[0028] The present invention will be further described below with reference to the following embodiments.

[0029] Example 1 A high-adhesion special film includes, from top to bottom, a first metal layer, a first adhesive layer, a polymer base film layer, a second adhesive layer, and a second metal layer. The polymer base film layer is made of homopolymer polyimide (PI, DuPont Kapton H), and its thickness is 12 μm. All metal layers are made of copper and have a thickness of 300 nm. All adhesive layers have a thickness of 1.5 μm.

[0030] The adhesive layer comprises, by weight, parts of: 100 parts polyether modified epoxy resin, 15 parts nano-reinforcing filler, 1.6 parts silane coupling agent, 0.3 parts defoamer, 20 parts curing agent and 300 parts solvent.

[0031] The polyether-modified epoxy resin is Aidico EP-4000; the silane coupling agent is γ-aminopropyltriethoxysilane; the defoamer is BYK-A525; the curing agent is Wanhua TSG-7190; and the solvent is toluene.

[0032] The preparation method of the nano-reinforced filler includes: S1. Under nitrogen protection, 10.8 g of p-phenylenediamine was weighed and added to 150 mL of N,N-dimethylformamide. After mixing thoroughly at room temperature, 29.9 g of 3,3',4,4'-biphenyltetracarboxylic dianhydride was added. The temperature was raised to 40 °C and stirred for 10 h to obtain an anhydride-terminated polyimide precursor solution. S2. Weigh 100 mL of water and 150 mL of N,N-dimethylformamide and mix them. Add 13.3 g of scandium acetate (Sc(OAc)3) and 10.6 g of yttrium acetate (Y(OAc)3). After dissolving completely, add 32.5 g of 2,3,6,7,10,11-hexaaminotriphenyl (HATP). Sonicate the mixture at room temperature for 1.5 h. Then transfer the mixed solution to a reaction vessel and solvothermal react at 90 °C for 15 h. After the reaction is complete, allow it to cool naturally. Wash the mixture three times by centrifugation with acetone and water, and then vacuum dry to obtain amino framework two-dimensional nanomaterials. Under the protection of nitrogen, 5.5 g of amino framework two-dimensional nanomaterials were added to 100 mL of anhydride-terminated polyimide precursor solution. After thorough mixing at room temperature, the mixture was heated to 35 °C and stirred for 8 h. Then, 10 g of acetic anhydride dehydrating agent and 5 g of triethylamine catalyst were added, the mixture was heated to 110 °C and stirred for 8 h. The solvent was removed by vacuum distillation, the mixture was washed three times with ethanol, dried under vacuum, and pulverized to obtain nano-reinforced fillers with a particle size of 200 nm.

[0033] The method for preparing the above-mentioned high-adhesion special film includes the following steps: Step 1, Prepare the adhesive coating solution: Weigh each component of the adhesive layer according to the weight proportions, place them in a high-speed disperser, disperse until a uniform and stable suspension is formed, and filter with a 400-mesh filter. Step 2, Coating and curing the adhesive layer: Apply the adhesive coating liquid to the surface of the base film, and then place the coated film in an oven for curing. First, cure it in an oven at 80℃ for 1.5 minutes, and then raise the temperature to 120℃ for 3 minutes to complete the initial cross-linking and shaping of the adhesive layer. Step 3, Depositing the metal layer: The cured film material of the adhesive layer is sent into the magnetron sputtering vacuum chamber, and under argon protection, the vacuum degree is controlled at 5×10⁻⁶. -3 Metal target material is sputtered and deposited on the adhesive layer of the membrane material at a pressure of 0.8 Pa and a power density of 3 W / cm³. 2 The deposition reaches the required thickness; Step 4, post-processing: Place the film with the deposited metal layer in a curing chamber at 50°C for 24 hours, and finally rewind it to complete the preparation.

[0034] Example 2 A high-adhesion special film includes, from top to bottom, a metal layer, an adhesive layer, and a polymer base film layer. The adhesive layer has a thickness of 1 μm. The polymer base film layer is made of polyethylene terephthalate (PET) and has a thickness of 8 μm. The metal layer is aluminum and has a thickness of 200 nm.

[0035] The adhesive layer comprises, by weight, parts of: 80 parts polyether modified epoxy resin, 5 parts nano-reinforcing filler, 0.5 parts silane coupling agent, 0.1 parts defoamer, 10 parts curing agent and 200 parts solvent.

[0036] The polyether-modified epoxy resin is Cellway HQ-500. The silane coupling agent is γ-aminopropylmethyldiethoxysilane. The defoamer is BYK-065. The curing agent is Momentive 8140. The solvent is isopropanol.

[0037] The preparation method of the nano-reinforced filler includes: S1. Under nitrogen protection, 10.8 g of p-phenylenediamine was weighed and added to 100 mL of N,N-dimethylformamide. After mixing thoroughly at room temperature, 29.7 g of 3,3',4,4'-biphenyltetracarboxylic dianhydride was added. The temperature was raised to 35 °C and stirred for 8 h to obtain an anhydride-terminated polyimide precursor solution. S2. Weigh 50 mL of water and 100 mL of N,N-dimethylformamide and mix them. Add 6.7 g of scandium acetate (Sc(OAc)3) and 8.1 g of yttrium acetate (Y(OAc)3). After dissolving completely, add 31.8 g of 2,3,6,7,10,11-hexaaminotriphenyl (HATP). Sonicate the mixture at room temperature for 1 h. Then transfer the mixed solution to a reaction vessel and solvothermal react at 80 °C for 10 h. After the reaction is complete, allow it to cool naturally. Wash the mixture three times by centrifugation with acetone and water, and then vacuum dry to obtain amino framework two-dimensional nanomaterials. Under the protection of nitrogen, 2.5g of amino framework two-dimensional nanomaterials were added to 100mL of anhydride-terminated polyimide precursor solution. After thorough mixing at room temperature, the mixture was heated to 30℃ and stirred for 6h. Then, 5g of acetic anhydride dehydrating agent and 2g of triethylamine catalyst were added, the mixture was heated to 100℃ and stirred for 6h. The solvent was removed by vacuum distillation, the mixture was washed three times with ethanol, dried under vacuum, and pulverized to obtain the nano-reinforced filler.

[0038] The method for preparing the above-mentioned high-adhesion special film includes the following steps: Step 1, Prepare the adhesive coating solution: Weigh each component of the adhesive layer according to the weight proportions, place them in a high-speed disperser, disperse until a uniform and stable suspension is formed, and filter with a 400-mesh filter. Step 2, Coating and curing the adhesive layer: Coating the adhesive layer coating liquid onto the surface of the base film, and then placing the coated film material in an oven for curing treatment. First, cure it in an oven at 80℃ for 1 minute, and then raise the temperature to 120℃ for 2 minutes to complete the initial cross-linking and shaping of the adhesive layer. Step 3, Depositing the metal layer: The cured film material of the adhesive layer is sent into the magnetron sputtering vacuum chamber, and under argon protection, the vacuum degree is controlled at 5×10⁻⁶. -3Metal target material is sputtered and deposited on the adhesive layer of the membrane material at a pressure of 0.5 Pa and a power density of 2 W / cm³. 2 The deposition reaches the required thickness; Step 4, post-processing: Place the film with the deposited metal layer in a curing chamber at 50°C for 24 hours, and finally rewind it to complete the preparation.

[0039] Example 3 A special film with high adhesion includes, from top to bottom, a first metal layer, a first adhesive layer, a polymer base film layer, a second adhesive layer, and a second metal layer. The thickness of the adhesive layer is 2 μm.

[0040] The polymer-based film layer is made of polypropylene (PP) and has a thickness of 15 μm. The metal layer is made of copper and has a thickness of 300 nm.

[0041] The adhesive layer comprises, by weight, parts of: 120 parts polyether modified epoxy resin, 25 parts nano-reinforcing filler, 3 parts silane coupling agent, 0.5 parts defoamer, 30 parts curing agent and 400 parts solvent.

[0042] The polyether-modified epoxy resin is Adico EP-1307. The silane coupling agent is N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane. The defoamer is DS8750. The curing agent is Huntsman D-230. The solvent is N-methylpyrrolidone.

[0043] The preparation method of the nano-reinforced filler includes: S1. Under the protection of nitrogen, 10.8 g of p-phenylenediamine was weighed and added to 200 mL of N,N-dimethylformamide. After mixing thoroughly at room temperature, 30.1 g of 3,3',4,4'-biphenyltetracarboxylic dianhydride was added. The temperature was raised to 45 °C and stirred for 12 h to obtain an anhydride-terminated polyimide precursor solution. S2. Weigh 150 mL of water and 200 mL of N,N-dimethylformamide and mix them. Add 15.5 g of scandium acetate (Sc(OAc)3) and 18.6 g of yttrium acetate (Y(OAc)3). After dissolving completely, add 33.4 g of 2,3,6,7,10,11-hexaaminotriphenyl (HATP). Sonicate the mixture at room temperature for 2 h. Then transfer the mixed solution to a reaction vessel and solvothermal react at 100 °C for 20 h. After the reaction is complete, allow it to cool naturally. Wash the mixture three times by centrifugation with acetone and water, and then vacuum dry to obtain amino framework two-dimensional nanomaterials. Under the protection of nitrogen, 8.5 g of amino framework two-dimensional nanomaterials were added to 100 mL of anhydride-terminated polyimide precursor solution. After thorough mixing at room temperature, the mixture was heated to 40 °C and stirred for 10 h. Then, 15 g of acetic anhydride dehydrating agent and 8 g of triethylamine catalyst were added. The mixture was heated to 120 °C and stirred for 10 h. The solvent was removed by vacuum distillation, and the mixture was washed three times with ethanol, dried under vacuum, and pulverized to obtain the nano-reinforced filler.

[0044] The method for preparing the above-mentioned high-adhesion special film includes the following steps: Step 1, Prepare the adhesive coating solution: Weigh each component of the adhesive layer according to the weight proportions, place them in a high-speed disperser, disperse until a uniform and stable suspension is formed, and filter with a 400-mesh filter. Step 2, Coating and curing the adhesive layer: Coat the surface of the base film with the adhesive layer coating liquid, and then place the coated film material in an oven for curing treatment. First, cure in an oven at 80℃ for 2 minutes, and then raise the temperature to 120℃ for 5 minutes to complete the initial cross-linking and shaping of the adhesive layer. Step 3, Depositing the metal layer: The cured film material of the adhesive layer is sent into the magnetron sputtering vacuum chamber, and under argon protection, the vacuum degree is controlled at 5×10⁻⁶. -3 At a pressure of 1.0 Pa and a power density of 2-4 W / cm³, a metal target is sputtered onto the adhesive layer of the membrane material. 2 The deposition reaches the required thickness; Step 4, post-processing: Place the film with the deposited metal layer in a curing chamber at 50°C for 24 hours, and finally rewind it to complete the preparation.

[0045] Comparative Example 1 A special membrane differs from Example 1 in that the nano-reinforcing filler in the adhesive layer is replaced with polyimide nanomaterials, while the other components and preparation process remain unchanged.

[0046] The preparation method of the polyimide nanomaterial includes: S1. Under nitrogen protection, 10.8 g of p-phenylenediamine was weighed and added to 150 mL of N,N-dimethylformamide. After mixing thoroughly at room temperature, 29.9 g of 3,3',4,4'-biphenyltetracarboxylic dianhydride was added. The temperature was raised to 40 °C and stirred for 10 h to obtain an anhydride-terminated polyimide precursor solution. Under the protection of S2 and nitrogen, 10g of acetic anhydride and 5g of triethylamine catalyst were added to 100mL of anhydride-terminated polyimide precursor solution. The temperature was raised to 110℃ and stirred for 8h. The solvent was removed by vacuum distillation, and the mixture was washed three times with ethanol, dried under vacuum, and pulverized to obtain polyimide nanomaterials with a particle size of 200nm.

[0047] Comparative Example 2 A special membrane differs from Example 1 in that the preparation process of the nano-reinforcing filler in the adhesive layer is different (only scandium is used in the metal framework), while the other components and preparation process remain unchanged.

[0048] The preparation method of the nano-reinforced filler includes: S1. Under nitrogen protection, 10.8 g of p-phenylenediamine was weighed and added to 150 mL of N,N-dimethylformamide. After mixing thoroughly at room temperature, 29.9 g of 3,3',4,4'-biphenyltetracarboxylic dianhydride was added. The temperature was raised to 40 °C and stirred for 10 h to obtain an anhydride-terminated polyimide precursor solution. S2. Weigh 100 mL of water and 150 mL of N,N-dimethylformamide and mix them. Add 23.9 g of scandium acetate (Sc(OAc)3) and dissolve it completely. Then add 32.5 g of 2,3,6,7,10,11-hexaaminotriphenyl (HATP) and sonicate at room temperature for 1.5 h. Then transfer the mixed solution to a reaction vessel and solvothermal react at 90 °C for 15 h. After the reaction is completed, cool naturally and wash three times with acetone and water by centrifugation. Vacuum dry to obtain amino framework two-dimensional nanomaterials. Under the protection of nitrogen, 5.5 g of amino framework two-dimensional nanomaterials were added to 100 mL of anhydride-terminated polyimide precursor solution. After thorough mixing at room temperature, the mixture was heated to 35 °C and stirred for 8 h. Then, 10 g of acetic anhydride dehydrating agent and 5 g of triethylamine catalyst were added, the mixture was heated to 110 °C and stirred for 8 h. The solvent was removed by vacuum distillation, the mixture was washed three times with ethanol, dried under vacuum, and pulverized to obtain nano-reinforced fillers with a particle size of 200 nm.

[0049] Comparative Example 3 A special membrane differs from Example 1 in that the preparation process of the nano-reinforcing filler in the adhesive layer is different (the metal framework uses only yttrium), while the other components and preparation process remain unchanged.

[0050] The preparation method of the nano-reinforced filler includes: S1. Under nitrogen protection, 10.8 g of p-phenylenediamine was weighed and added to 150 mL of N,N-dimethylformamide. After mixing thoroughly at room temperature, 29.9 g of 3,3',4,4'-biphenyltetracarboxylic dianhydride was added. The temperature was raised to 40 °C and stirred for 10 h to obtain an anhydride-terminated polyimide precursor solution. S2. Weigh 100 mL of water and 150 mL of N,N-dimethylformamide and mix them. Add 23.9 g of yttrium acetate (Y(OAc)3) and dissolve it completely. Then add 32.5 g of 2,3,6,7,10,11-hexaaminotriphenyl (HATP) and sonicate at room temperature for 1.5 h. Then transfer the mixed solution to a reaction vessel and solvothermal react at 90 °C for 15 h. After the reaction is complete, cool naturally and wash three times with acetone and water by centrifugation. Vacuum dry to obtain amino framework two-dimensional nanomaterials. Under the protection of nitrogen, 5.5 g of amino framework two-dimensional nanomaterials were added to 100 mL of anhydride-terminated polyimide precursor solution. After thorough mixing at room temperature, the mixture was heated to 35 °C and stirred for 8 h. Then, 10 g of acetic anhydride dehydrating agent and 5 g of triethylamine catalyst were added, the mixture was heated to 110 °C and stirred for 8 h. The solvent was removed by vacuum distillation, the mixture was washed three times with ethanol, dried under vacuum, and pulverized to obtain nano-reinforced fillers with a particle size of 200 nm.

[0051] Experimental Example The performance of the special membranes prepared in Example 1 and Comparative Examples 1-3 was tested, and all tests were conducted in accordance with national or international standards.

[0052] The testing items include: Mechanical properties (tensile strength and elongation at break, refer to ASTM D882, universal testing machine, tensile rate 50 mm / min), adhesion properties (tenacity, refer to ASTM D4541 (pull-out method)), dielectric properties (dielectric constant and dielectric loss, refer to ASTM D150, 25°C, 1 kHz), high temperature resistance (high temperature tensile strength tested according to ASTM D4541 after treatment at 120°C for 2 hours).

[0053] The test results are shown in Table 1: Table 1 Performance test results of different special membranes As shown in Table 1, the mechanical properties, dielectric properties, adhesion properties, and high-temperature resistance of Example 1 are superior to those of the other comparative examples. Compared with Comparative Examples 2 and 3, the bimetallic system of Example 1 optimizes the electronic structure and interfacial binding energy of the MOF, providing more binding sites and a more stable structure than a single metal. Comparative Example 1 performed the worst, possibly because it uses traditional polyimide nanomaterials, which rely entirely on weak physical adsorption and limited polarity, lacking the strong interfacial anchoring and synergistic enhancement effects of MOFs.

[0054] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. The illustrative expressions of the above terms in this specification should not be construed as necessarily referring to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0055] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A special film with high adhesion, characterized by, The special film comprises a polymer base film, an adhesive layer arranged on at least one side of the polymer base film, and a metal layer arranged on the adhesive layer; The adhesive layer comprises, in terms of weight fractions, 80-120 parts of polyether modified epoxy resin, 5-25 parts of nano-enhanced filler, 0.5-3 parts of silane coupling agent, 0.1-0.5 parts of defoaming agent, 10-30 parts of curing agent, and 200-400 parts of solvent. The special film comprises, from top to bottom, a first metal layer, a first adhesive layer, a polymer base film layer, a second adhesive layer, and a second metal layer.

2. The special film with high adhesion according to claim 1, characterized in that, The polymer base film layer is made of one of polyethylene terephthalate, polypropylene, polyimide, and polyethylene naphthalate.

3. The high adhesion special film according to claim 1, characterized in that, The thickness of the polymer base film layer is 2-20 microns, the thickness of the metal layer is 20-500 nanometers, and the thickness of the adhesive layer is 1-2 microns.

4. The high adhesion special film according to claim 1, characterized in that, The polyether modified epoxy resin is at least one of EP-4000, HQ-5000, and EP-1307; the defoaming agent is at least one of BYK-A525, BYK-065, and DS8750; and the curing agent is an amine curing agent, including at least one of TSG-7190, 8140, and D-230.

5. The high adhesion special film according to claim 1, characterized in that, The preparation method of the nano-enhanced filler comprises:

6. The high adhesion special film according to claim 1, characterized in that, S1, under the protection of nitrogen, p-phenylenediamine is weighed and added to N,N-dimethylformamide, mixed thoroughly at room temperature, then 3,3',4,4'-biphenyl tetracarboxylic dianhydride is added, the temperature is raised to 35-45 DEG C, and the mixture is stirred for 8-12 hours to obtain an anhydride-terminated polyimide precursor solution; S2, water and N,N-dimethylformamide are weighed and mixed, scandium acetate and yttrium acetate are added, dissolved thoroughly, then 2,3,6,7,10,11-hexaaminotriphenyl is added, ultrasonic treatment is carried out at room temperature for 1-2 hours, then the mixed solution is transferred into a reaction kettle, and solvent thermal reaction is carried out at 80-100 DEG C for 10-20 hours, and post-treatment is carried out to obtain an amino framework two-dimensional nanomaterial; S3, under the protection of nitrogen, the amino framework two-dimensional nanomaterial is added to the anhydride-terminated polyimide precursor solution, mixed thoroughly at room temperature, the temperature is raised to 30-40 DEG C, and the mixture is stirred for 6-10 hours, then dehydrating agent acetic anhydride and catalyst triethylamine are added, the temperature is raised to 100-120 DEG C, and the mixture is stirred for 6-10 hours, and post-treatment is carried out to obtain the nano-enhanced filler. In S1, the ratio of p-phenylenediamine, 3,3',4,4'-biphenyl tetracarboxylic dianhydride and N,N-dimethylformamide is 10.8 g:(29.7-30.1) g:(100-200) mL.

7. The high adhesion special film according to claim 6, characterized in that, In S2, the ratio of scandium acetate, yttrium acetate, 2,3,6,7,10,11-hexaaminotriphenyl, water and N,N-dimethylformamide is (6.7-15.5) g:(8.1-18.6) g:(31.8-33.4) g:(50-150) mL:(100-200) mL.

8. The high adhesion special film according to claim 6, characterized in that, ​ 9. The high adhesion special film according to claim 6, characterized in that, In the S3, the ratio of the amino framework two-dimensional nanomaterial and the acid anhydride-terminated polyimide precursor solution is (2.5-8.5) g:100 mL; the dehydrating agent is acetic anhydride, the catalyst is triethylamine, and the ratio of the dehydrating agent, the catalyst and the acid anhydride-terminated polyimide precursor solution is (5-15) g:(2-8) g:100 mL.

10. A method of producing the high-adhesion special film according to claim 1, characterized by, The method comprises the following steps: Step 1, configuring an adhesive layer coating solution: ingredients of the adhesive layer are weighed according to the weight ratio, placed in a high-speed disperser, dispersed until a uniform suspension is formed, and filtered through a filter screen; Step 2, coating and curing the adhesive layer: the adhesive layer coating solution is coated on the surface of the base film, and then the coated film material is placed in an oven for curing treatment, so that the adhesive layer is preliminarily crosslinked and shaped; Step 3, depositing a metal layer: the film material after curing of the adhesive layer is sent into a magnetron sputtering vacuum chamber, a metal target material is sputtered and deposited on the adhesive layer of the film material, and the deposition reaches the required thickness; Step 4, post-treatment: the film material with the deposited metal layer is aged in an aging chamber, and finally wound, so that the preparation is completed.

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