Ultrathin high-viscosity graphene heat-conducting double-sided adhesive tape and preparation method thereof

Abstract

The invention relates to the technical field of thermal management materials, discloses an ultrathin high-viscosity graphene heat-conducting double-sided adhesive tape and a preparation method thereof, and aims to solve the problems that in the prior art, the heat-conducting property and the adhesive property are difficult to adjust, a heat-conducting filler is easy to agglomerate and disperse, a heat-conducting network is difficult to construct or the adhesive force is damaged. The adhesive tape is provided with a composite adhesive layer, and is characterized by being composed of a three-dimensional continuous porous graphene network skeleton, a functional interface layer chemically grafted on the surface of the skeleton, and a high-molecular adhesive matrix which fills the interior of the skeleton and is chemically bonded with the interface layer. The preparation method comprises the steps of skeleton construction, surface functionalization, monomer infiltration and in-situ curing molding. By the adoption of the technical scheme, the characteristics of high heat conduction, high adhesion, ultra-thinness and static electricity resistance can be achieved.

Description

Technical Field

[0001] This invention belongs to the field of thermal management materials technology, specifically, it relates to an ultrathin, high-viscosity graphene thermally conductive double-sided tape and its preparation method. Background Technology

[0002] Against the backdrop of the continuous evolution of electronic information technology towards high power density, miniaturization, and high functional integration, the operating power consumption and heat flux density per unit volume of electronic components have increased dramatically. This has made thermal management a key technological bottleneck restricting their performance, reliability, and lifespan. In this context, thermally conductive double-sided tape, as a crucial material for connecting and securing precision electronic components, plays a role far beyond its traditional mechanical holding function; it also bears the important mission of constructing efficient and stable heat conduction paths. These functional tapes must, within a limited structural space, rapidly and effectively transfer waste heat generated by core heat sources such as chips and power devices to heat sinks or housings, thereby ensuring the stable operation of the entire electronic system. Therefore, developing thermally conductive double-sided tapes that combine excellent adhesion, superior thermal conductivity, and ultra-thin dimensions is of vital technological value for promoting the development of modern electronics manufacturing.

[0003] In existing technologies, to impart thermal conductivity to polymer tapes, a common approach is to physically blend high-thermal-conductivity inorganic or carbon-based fillers into an acrylic or silicone-based polymer adhesive matrix. Specifically, this approach relies on incorporating ceramic microparticles such as alumina or boron nitride, or carbon material powders such as graphite or carbon nanotubes, into a liquid adhesive at a specific mass or volume fraction, followed by coating and curing to create a composite adhesive layer. The underlying thermal conductivity mechanism is based on the expectation that these dispersed, high-thermal-conductivity filler particles will contact each other or be sufficiently close within the insulating polymer matrix, forming a three-dimensional network capable of conducting phonons—the so-called "thermal conduction pathway." At a specific stage of technological development, this "polymer matrix-thermal-conducting filler" composite system effectively addressed the heat dissipation requirements of electronic devices at the time. By controlling the type, particle size, morphology, and proportion of the filler, a balance between thermal conductivity and adhesive properties could be achieved to a certain extent, forming the technological basis for current mainstream products.

[0004] However, with the continuous development of related technologies and the increasingly stringent requirements for performance indicators in application scenarios, the aforementioned technical paradigm based on physical blending and filling has begun to reveal profound limitations in its inherent physical mechanisms, particularly in the synergistic improvement of the two core indicators of high adhesion and high thermal conductivity, where it has encountered an irreconcilable bottleneck. The reason for this lies in a fundamental contradiction within this technical system: the inherent conflict between the "percolation threshold" required for constructing the thermally conductive network and the "matrix continuity" required to maintain the adhesive's bonding performance. On the one hand, to form an effective thermally conductive pathway throughout the entire adhesive layer, the volume fraction of the thermally conductive filler must reach a critical value, namely the percolation threshold. Below this threshold, the filler particles are isolated and dispersed in the polymer ocean, unable to form continuous heat flow channels, resulting in limited improvement in macroscopic thermal conductivity. On the other hand, the adhesive properties of pressure-sensitive tapes, such as peel strength, shear strength, and holding power, are physically based on the full wetting, entanglement, and van der Waals forces of polymer chains. This requires the adhesive matrix to maintain its macroscopic continuity and the mobility of chain segments. When a large amount of filler is added to overcome the thermal conductivity percolation threshold, the continuity of the polymer matrix is ​​severely disrupted and damaged by countless filler particles. The activity space of the polymer chains is restricted, and their wetting ability on the adhered surface is greatly reduced. At the same time, the cohesive force within the adhesive layer is weakened due to the reduced matrix proportion, ultimately leading to a sharp deterioration in adhesive performance. Furthermore, this contradiction becomes particularly acute when graphene, a two-dimensional material with ultra-high intrinsic thermal conductivity, is introduced as a filler. Graphene sheets have a huge specific surface area and extremely strong interlayer π-π stacking effects, making them exhibit extremely poor compatibility and dispersibility in common non-polar or weakly polar adhesive matrices, and they are prone to irreversible agglomeration. These agglomerates not only fail to form an ideal, regularly oriented thermally conductive network, but also severely hinder phonon transport due to their large amount of interfacial thermal resistance and random structure. Meanwhile, these micron-sized or even larger agglomerates act as defects and stress concentration points in the adhesive layer, causing even more serious damage to the mechanical properties and adhesive reliability of the tape. This leads to a technical dilemma: graphene cannot effectively disperse and form a thermally conductive network at the low filler content allowed to maintain high viscosity; while increasing the filler content to force the formation of a thermally conductive network will cause severe agglomeration and a collapse in adhesion properties.

[0005] Therefore, the fundamental challenge of existing technologies is no longer simply finding fillers with higher thermal conductivity, but rather how to fundamentally overcome the inherent contradiction between the thermal percolation threshold and the continuity of the adhesive matrix in physical blend systems. How to achieve a leapfrog improvement in thermal conductivity without significantly sacrificing the continuity of the polymer matrix and ensuring high adhesion performance, by surface functionalizing or constructing pre-organized structures for high-performance fillers such as graphene, and inducing them to spontaneously form an ordered and efficient three-dimensional thermally conductive network in the adhesive matrix, at filler addition amounts far below the traditional percolation threshold, and further integrating additional properties such as antistatic and highly transparent release films to meet the needs of precision electronic assembly, has become a key challenge and an urgent technical problem for those skilled in the art. Summary of the Invention

[0006] The purpose of this invention is to overcome the fundamental contradiction inherent in existing technologies that involve physically blending thermally conductive fillers into a polymer adhesive matrix, where the thermal conductivity and adhesive properties are difficult to reconcile. Specifically, it addresses the technical dilemma of two-dimensional thermally conductive fillers such as graphene, which, due to their percolation threshold requirements and tendency to agglomerate and disperse poorly in the matrix, cannot construct an effective thermally conductive network with the low filler content required to maintain high adhesive performance, while high filler content severely disrupts the continuity of the adhesive matrix and causes adhesive strength collapse. To achieve the above-mentioned objective, this invention provides an ultrathin, high-adhesion graphene thermally conductive double-sided tape and its preparation method. This technical solution fundamentally abandons the thermal conductivity mechanism based on physical blending percolation, instead employing a pre-constructed, functionalized, and in-situ chemically bonded three-dimensional continuous thermally conductive network architecture. This achieves excellent thermal conductivity, high peel strength adhesive performance, ultrathin physical dimensions, and integrated antistatic properties simultaneously with an extremely low graphene volume fraction.

[0007] To achieve the above objectives, a first aspect of the present invention provides an ultrathin, high-adhesion graphene thermally conductive double-sided adhesive tape, which structurally comprises a composite adhesive layer composed of the following components: A three-dimensional continuous porous graphene network framework macroscopically spans the entire three-dimensional volume of the composite adhesive layer, forming a physically continuous pathway for phonon and electron transport. The three-dimensional continuous porous graphene network framework has a volume porosity greater than 95%, with an average pore size ranging from 50 micrometers to 300 micrometers. The graphene network framework is formed by growing a single layer or a few layers of graphene sheets on a three-dimensional porous template via chemical vapor deposition and then removing the template. Its inherent three-dimensional interconnected structure ensures the continuity of the heat flow path from one main surface of the composite adhesive layer to the opposite main surface. The mass fraction of the graphene network framework in the composite adhesive layer is less than 5%.

[0008] A surface-functionalized interface layer is chemically grafted onto all exposed surfaces of the three-dimensional continuous porous graphene network framework, serving as a chemical bridge connecting the inorganic graphene framework and the organic polymer adhesive matrix. The surface-functionalized interface layer is a product formed by the chemical reaction of a specific silane coupling agent with a surface-activated graphene surface. The silane coupling agent contains at least one group in its molecular structure that can react with active sites on the graphene surface (such as hydroxyl or carboxyl groups) to form stable covalent bonds (such as siloxane bonds), and at the other end of its molecular structure, it contains at least one active functional group capable of participating in the subsequent in-situ polymerization reaction of the polymer adhesive matrix. Specifically, the active functional group is methacryloyloxy. The silane coupling agent is 3-(methacryloyloxypropyl)trimethoxysilane.

[0009] A polymeric adhesive matrix completely fills the internal pores of a three-dimensional continuous porous graphene network framework coated with a surface-functionalized interface layer, and is chemically bonded to the surface-functionalized interface layer. The polymeric adhesive matrix is ​​formed by in-situ free radical polymerization within the graphene network framework using a premix containing at least two acrylate monomers. A robust covalent bond is formed between the polymeric adhesive matrix and the surface-functionalized interface layer through a copolymerization reaction involving the methacryloxy functional groups. This structure allows the polymeric adhesive matrix to be microscopically segmented by the graphene network, but macroscopically interconnected through pores, maintaining the necessary chain mobility and wetting ability for a pressure-sensitive adhesive.

[0010] Specifically, the polymer adhesive matrix is ​​prepared by in-situ polymerization of the following raw materials in parts by weight: 70 parts by weight of butyl acrylate as the main monomer that imparts flexibility and initial tack to the adhesive; 28 parts by weight of methyl methacrylate as a comonomer that improves the cohesive strength and glass transition temperature of the adhesive; 1 part by weight of 1,6-hexanediol diacrylate as a crosslinking agent to form a suitable network structure during polymerization to improve holding power and temperature resistance; and 1 part by weight of 1-hydroxycyclohexylphenyl ketone as a photoinitiator to initiate free radical polymerization under ultraviolet irradiation of a specific wavelength.

[0011] Furthermore, the ultrathin high-viscosity graphene thermally conductive double-sided adhesive tape also includes a first release layer and a second release layer symmetrically disposed on the two main surfaces of the composite adhesive layer. Both the first and second release layers are 50-micron-thick polyethylene terephthalate (PET) films, with a 1-micron-thick polydimethylsiloxane release agent coating on the side facing the composite adhesive layer. The peel force between this release agent coating and the composite adhesive layer is 0.05 N / 25 mm under a 180-degree peel test.

[0012] In a preferred embodiment of the present invention, to impart antistatic function to the double-sided adhesive tape, a conductive coating is applied to the outer surface of the first release layer (i.e., the surface not in contact with the composite adhesive layer). The surface resistivity of this conductive coating is 10^6 to 10^9 Ω / sq. The conductive coating is a conductive polymer coating based on poly(3,4-ethylenedioxythiophene):polystyrene sulfonic acid (PEDOT:PSS). Due to its inherent conductivity, the interconnected structure of the three-dimensional continuous porous graphene network framework gives the composite adhesive layer overall volume conductivity, which can effectively dissipate surface static charge when bonded to the release layer with the conductive coating.

[0013] A second aspect of the present invention provides a method for preparing the above-mentioned ultrathin, high-viscosity graphene thermally conductive double-sided adhesive tape. This method abandons the traditional physical blending-coating-curing process and instead adopts a multi-step, precisely controlled integrated process of template-growth-functionalization-wetting-in-situ polymerization, specifically including the following steps: Step 1: Construction of a three-dimensional continuous porous graphene network framework. A three-dimensional porous nickel foam was selected as the sacrificial template. The nickel foam had a thickness of 100 micrometers, a pore density of 100 PPI (pores per inch), and a volumetric porosity greater than 97%. The nickel foam template was placed in the center of the quartz tube of a tubular chemical vapor deposition (CVD) furnace. Under a mixed atmosphere of argon and hydrogen (volume ratio 4:1, total flow rate 205 sccm), the furnace temperature was programmed to rise to 1000°C at a rate of 20°C / min. The nickel foam template was annealed at 1000°C for 30 minutes. Subsequently, the hydrogen supply was cut off, and methane (CH4) at a flow rate of 10 sccm was introduced as the carbon source gas. The graphene growth reaction was carried out at 1000°C and atmospheric pressure for 15 minutes. After the reaction, the methane supply was stopped, and the furnace was naturally cooled to room temperature in an argon atmosphere to obtain a composite nickel foam structure with its surface completely covered by a graphene layer.

[0014] Step Two: Removal of the Sacrificial Template. The graphene-coated composite nickel foam structure obtained in Step One was completely immersed in a 3 mol / L hydrochloric acid aqueous solution and chemically etched in a 60°C water bath for 8 hours until the nickel foam template was completely corroded and dissolved. During the reaction, hydrochloric acid reacted with nickel to form nickel chloride, which dissolved in the water, while the chemically stable graphene structure was completely preserved, forming a self-supporting three-dimensional continuous porous graphene network framework that was completely identical to the original nickel foam template structure. Subsequently, the graphene network framework was repeatedly rinsed with a large amount of deionized water until the pH of the washing solution was 7 to thoroughly remove residual acid and nickel ions. Finally, the cleaned graphene network framework was freeze-dried to remove moisture while preserving its original three-dimensional porous structure to the greatest extent possible, resulting in a dried three-dimensional graphene network framework.

[0015] Step 3: Surface Functionalization of the Graphene Network Framework. This step consists of two sub-steps: surface activation and coupling agent grafting. First, surface activation is performed. The dried three-dimensional graphene network framework obtained in Step 2 is placed in the chamber of a plasma reactor and subjected to plasma treatment under an oxygen atmosphere. Specific process parameters are: oxygen flow rate of 50 sccm, chamber pressure maintained at 50 Pa, RF power of 100 W, and treatment time of 180 seconds. This treatment introduces oxygen-containing functional groups, mainly hydroxyl (-OH) and carboxyl (-COOH) groups, into the defect sites and edges of the sp2 carbon lattice of graphene, providing active reaction sites for subsequent chemical grafting.

[0016] Next, coupling agent grafting was performed. The surface-activated three-dimensional graphene network framework was immersed in a pre-prepared coupling agent solution. This coupling agent solution was prepared by dissolving 2 parts by volume of 3-(methacryloyloxypropyl)trimethoxysilane (TMSPMA) in 98 parts by volume of anhydrous toluene. Under a nitrogen atmosphere, the system was heated to 80°C and magnetically stirred for 12 hours. During this process, the methoxysilyl groups in the TMSPMA molecules underwent a hydrolytic condensation reaction with the hydroxyl groups on the graphene surface, forming stable Si-OC covalent bonds, thereby firmly grafting the organic molecular chain containing the methacryloyloxy functional group onto the surface of the graphene framework. After the reaction, the functionalized graphene network framework was removed and ultrasonically cleaned sequentially with toluene and ethanol to remove physically adsorbed, unreacted TMSPMA molecules. Finally, it was dried in a vacuum oven at 60°C for 4 hours to obtain a functionalized three-dimensional graphene network framework with polymeric active groups grafted onto its surface.

[0017] Step 4: Preparation and impregnation of the adhesive monomer premix. Following the aforementioned formulation, 70 parts by weight of butyl acrylate, 28 parts by weight of methyl methacrylate, 1 part by weight of 1,6-hexanediol diacrylate, and 1 part by weight of 1-hydroxycyclohexylphenyl ketone were mixed uniformly under light-protected conditions to prepare a transparent, homogeneous, low-viscosity adhesive monomer premix. The first release layer was laid flat on a clean, horizontal substrate, and the functionalized three-dimensional graphene network skeleton obtained in Step 3 was placed flat in the center of the release layer. Then, the prepared adhesive monomer premix was dripped onto the graphene network skeleton until it was completely covered. This assembly was placed in a vacuum impregnation apparatus, and the pressure inside the chamber was evacuated to 100 Pa and maintained for 5 minutes to remove air from the pores of the graphene skeleton. Then, the chamber was slowly restored to atmospheric pressure, and atmospheric pressure was used to force the monomer premix into each pore of the graphene skeleton, ensuring complete and bubble-free impregnation.

[0018] Step 5: In-situ curing and molding of the composite tape. After impregnation, the second release layer is carefully applied to the graphene skeleton impregnated with monomer premix, forming a sandwich structure of "release layer-composite adhesive layer-release layer". This sandwich structure assembly is passed through a pair of precisely gap-controlled rollers, with the gap set at 105 micrometers to ensure uniform thickness of the final composite adhesive layer. Next, the pressed assembly is transported to an ultraviolet (UV) curing device, where it is irradiated on both sides using a high-pressure mercury lamp with a center wavelength of 365 nm, with the irradiation energy dose controlled at 1000 mJ / cm². 2 Under ultraviolet light, the photoinitiator in the premix decomposes to generate free radicals, initiating a chain polymerization reaction of acrylate monomers. During this process, the methacryloxy functional groups grafted onto the graphene framework surface participate in the polymerization reaction as comonomers, firmly anchoring the growing polymer chains to the graphene framework through the formation of C-C covalent bonds. Simultaneously, the reaction of the crosslinking agent forms a three-dimensional polymer network structure. After the polymerization reaction is complete, a structurally stable, high-performance, ultra-thin, high-adhesion graphene thermally conductive double-sided adhesive tape is obtained. Cutting and winding the finished product completes all preparation steps.

[0019] The technical solution provided by this invention fundamentally changes the relationship between thermally conductive fillers and polymer matrices in traditional physical blending systems by pre-constructing a three-dimensional continuous graphene network framework, functionalizing its surface, and then generating a polymer binder matrix within the framework through in-situ polymerization to form chemical bonds. In this system, the graphene framework provides a highly efficient, continuous thermal conductivity channel at an extremely low mass fraction (less than 5%), and its thermal conductivity no longer depends on the percolation behavior of randomly distributed particles. Simultaneously, the polymer binder matrix maintains its macroscopic continuity and functional integrity, and the strong chemical bond interface between it and the graphene framework eliminates interfacial thermal resistance, significantly enhancing the overall mechanical properties and structural stability of the composite material. Therefore, this invention achieves a significant leap in thermal conductivity without sacrificing, and even enhances, adhesive performance, successfully resolving the fundamental contradictions in the prior art and providing a novel and highly practical material solution for thermal management of high-performance electronic devices. To make the objectives, technical solutions, and advantages of this invention clearer, the following will provide a comprehensive and detailed description of an ultrathin, high-viscosity graphene thermally conductive double-sided adhesive tape and its preparation method, in conjunction with specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the scope of protection of the invention. Any modifications, equivalent substitutions, or improvements made by those skilled in the art under the guidance of this invention should be included within the scope of protection claimed by this invention.

[0020] The core of the technical solution disclosed in this invention lies in constructing a composite adhesive layer that achieves functional separation of the thermally conductive pathway and the adhesive matrix at the microscopic level, yet forms a macroscopically unified whole through chemical bonding. This composite adhesive layer fundamentally abandons the traditional approach of relying on the physical blending of thermally conductive fillers in the matrix to reach a percolation threshold in order to form thermally conductive pathways. Instead, it pre-constructs a complete, continuous three-dimensional thermally conductive framework, and generates a polymeric adhesive matrix in situ within the porous structure of this framework. This achieves both excellent thermal conductivity and superior adhesive performance with extremely low levels of thermally conductive functional components.

[0021] In one specific embodiment, the present invention provides an ultrathin, high-adhesion graphene thermally conductive double-sided adhesive tape, the main structure of which is a composite adhesive layer. This composite adhesive layer comprises a three-dimensional continuous porous graphene network framework, a surface-functionalized interface layer chemically grafted onto the surface of the framework, and a polymeric adhesive matrix that completely fills the pores within the framework and chemically bonds with the interface layer.

[0022] Specifically, the three-dimensional continuous porous graphene network framework is the structural basis and core of the thermal conductivity of the composite adhesive layer. Macroscopically, it is a physically continuous mesh structure that runs through the entire three-dimensional volume of the composite adhesive layer. This continuity ensures an uninterrupted heat flow path composed of high-quality graphene from one main surface of the tape to the opposite main surface, thus providing a physical guarantee for efficient phonon transport. The framework has extremely high volumetric porosity; in a preferred embodiment, its volumetric porosity is greater than 95%, and can even reach over 97%. Such high porosity provides ample space for the subsequent filling of the polymer adhesive matrix, ensuring the macroscopic continuity and dominant position of the adhesive matrix. Simultaneously, the average pore size of its internal pores is precisely controlled between 50 micrometers and 300 micrometers. This pore size range ensures effective wetting of the adhesive monomer premix and allows for the formation of appropriately sized polymer microregions after curing, thereby maintaining the chain segment mobility necessary for the pressure-sensitive adhesive. The graphene network framework is formed by uniformly growing a single layer or a few layers of graphene on a three-dimensional porous metal foam (such as nickel foam) sacrificial template using chemical vapor deposition, followed by complete removal of the metal template using chemical etching. This method ensures that the graphene network perfectly replicates the three-dimensional interconnected structure of the template. Crucially, the mass fraction of this graphene network framework in the final composite adhesive layer is controlled at an extremely low level, typically below 5%, and in one specific embodiment, it is only 3%. This is due to both the extremely low density of graphene itself and the extremely high thermal conductivity of its three-dimensional network structure, achieving the target thermal conductivity without requiring a large amount of filler. Such a low filler content fundamentally avoids serious damage to the continuity of the polymer adhesive matrix, which is the structural basis for this invention to simultaneously achieve high thermal conductivity and high adhesive performance.

[0023] Furthermore, to address the inherent interfacial incompatibility between the inorganic graphene framework and the organic polymer binder matrix, and to eliminate the resulting significant interfacial thermal resistance, this invention introduces a surface-functionalized interface layer. This interface layer is not a physical coating, but rather a chemically grafted layer onto the entire exposed surface of a three-dimensional continuous porous graphene network framework. Essentially, it is a product of a chemical reaction between specific silane coupling agent molecules and a surface-activated graphene surface. The activation treatment, such as oxygen plasma treatment, aims to introduce oxygen-containing functional groups, primarily hydroxyl (-OH) and carboxyl (-COOH) groups, into the defect sites and edges of the sp2 carbon lattice of the graphene. These functional groups become the active reaction sites for subsequent chemical grafting. Subsequently, a special silane coupling agent, 3-(methacryloyloxypropyl)trimethoxysilane (TMSPMA), is used to react with the activated graphene framework. TMSPMA's molecular structure possesses dual functionality: the trimethoxysilyl group at one end, upon hydrolysis under specific conditions, can undergo a dehydration condensation reaction with the hydroxyl groups on the graphene surface, forming an extremely stable and hydrolysis-resistant silicon-oxygen-carbon (Si-OC) covalent bond, thus firmly anchoring the coupling agent molecule to the graphene framework surface; the methacryloyloxy functional group at the other end is an active group that can participate in free radical polymerization, serving as a co-reaction site for the subsequent in-situ polymerization reaction of the polymer adhesive matrix. In this way, a robust chemical bridge is established between the inorganic thermally conductive framework and the organic adhesive matrix, which originally had vastly different chemical properties, laying the foundation for their integrated fusion.

[0024] Based on this functional graphene network framework, a polymeric adhesive matrix is ​​generated through in-situ polymerization. The polymeric adhesive matrix completely fills the internal pores of the three-dimensional continuous porous graphene network framework coated with a surface-functionalized interface layer, and undergoes in-situ chemical bonding with the surface-functionalized interface layer. Specifically, a premix containing at least two acrylate monomers, a crosslinking agent, and a photoinitiator is first prepared. In one specific embodiment, the premix consists of the following parts by weight: 70 parts by weight of butyl acrylate, as the main monomer, whose lower glass transition temperature endows the final adhesive with the necessary softness, elasticity, and good wetting ability on the surface of the adhered object, and is the main source of the initial tack of the pressure-sensitive adhesive; 28 parts by weight of methyl methacrylate, as a comonomer, whose higher glass transition temperature can effectively improve the cohesive strength and modulus of the polymer, preventing creep or overflow of the adhesive under stress, thereby improving holding power and temperature resistance; 1 part by weight of 1,6- Hexanediol diacrylate, as a bifunctional crosslinking agent, allows the acrylate groups at both ends of its molecule to participate simultaneously in the growth of different polymer chains during polymerization, thereby forming chemical crosslinking points between chains and constructing a suitable three-dimensional network structure. This structure significantly enhances the shear strength and long-term tack of the adhesive. Additionally, 1 part by weight of 1-hydroxycyclohexylphenyl ketone, as a highly efficient type I photoinitiator, can rapidly decompose to generate free radicals under irradiation with ultraviolet light of a specific wavelength (such as 365 nm), thereby initiating the free radical polymerization reaction of the entire system.

[0025] This low-viscosity monomer premix was vacuum impregnated to completely and bubble-free penetrate and fill all the pores of the functionalized graphene network framework. Subsequently, in-situ polymerization was initiated using UV curing. During polymerization, not only did butyl acrylate, methyl methacrylate, and 1,6-hexanediol diacrylate copolymerize and crosslink, but more importantly, the methacryloyloxy functional groups grafted onto the graphene framework surface also participated as comonomers in the growing polymer chains. In this way, the growing polymer adhesive matrix was directly "stitched" to the surface of the graphene framework through stable carbon-carbon covalent bonds. This combination of in-situ polymerization and chemical bonding ensures that although the polymer adhesive matrix is ​​microscopically divided into countless tiny regions by the graphene network, it is macroscopically interconnected through pores, maintaining the macroscopic continuity and chain segment mobility necessary for its function as a pressure-sensitive adhesive. Meanwhile, the strong interfacial bonding force greatly enhances the overall mechanical properties and structural stability of the composite material, and eliminates interfacial voids, providing an unobstructed channel for the effective transmission of phonons between graphene and polymer.

[0026] To constitute a complete double-sided adhesive tape product, the ultra-thin high-adhesion graphene thermally conductive double-sided adhesive tape also symmetrically comprises a first release layer and a second release layer, respectively adhered to the two main surfaces of the composite adhesive layer. In a specific embodiment, both the first and second release layers are made of polyethylene terephthalate (PET) film with a thickness of 50 micrometers. PET film is widely used due to its excellent dimensional stability, mechanical strength, and surface smoothness. On the side facing the composite adhesive layer, a polydimethylsiloxane (PDMS) release agent coating with a thickness of approximately 1 micrometer is precisely coated. This release agent coating has extremely low surface energy, does not chemically react with the acrylic polymer adhesive matrix, and has poor physical wetting, thereby achieving a slight and stable peel force. Through precise control, the peel force between the release agent coating and the composite adhesive layer is set to 0.05N / 25mm under standard 180-degree peel test conditions. This peel force ensures that the release layer will not fall off on its own during storage and transportation, and can be easily peeled off by the user during use without leaving any residue on the adhesive layer surface.

[0027] In a preferred embodiment of the present invention, to meet the stringent requirements of modern precision electronic equipment for electrostatic protection, the double-sided tape of the present invention can also integrate antistatic function. Specifically, a conductive coating is applied to the outer surface of the first release layer, i.e., the surface that does not contact the composite adhesive layer. The surface resistivity of this conductive coating is controlled within the electrostatic dissipation range of 10^6 to 10^9 Ω / sq. In a specific embodiment, the conductive coating is an aqueous conductive polymer coating based on poly(3,4-ethylenedioxythiophene):polystyrene sulfonic acid (PEDOT:PSS), formed into a uniform thin film through a precise coating process. Its working mechanism is that when the tape is attached to the device before use, this conductive release layer can provide a lateral dissipation path for static charges that may be generated during operation. More importantly, since the composite adhesive layer in the present invention contains a three-dimensional continuous graphene network framework running through the entire structure, and graphene itself is an excellent electrical conductor, the composite adhesive layer itself possesses volumetric conductivity from one main surface to another. When the release layer with a conductive coating is bonded to this conductive composite adhesive layer, a complete system is formed that can effectively conduct and dissipate surface static charge, thus providing reliable electrostatic protection for sensitive electronic components.

[0028] In a second aspect, the present invention provides a systematic method for preparing the aforementioned ultrathin, high-viscosity graphene thermally conductive double-sided adhesive tape. This method differs significantly from the traditional physical blending-coating-drying process; it is an integrated process flow that incorporates multiple precisely controlled steps, including template growth, chemical etching, surface chemical functionalization, vacuum wetting, and in-situ photocuring.

[0029] The first step of this method is the construction of a three-dimensional continuous porous graphene network framework. The starting material for this step is a three-dimensional mesh-like porous nickel foam, which is used as a sacrificial template. In one specific embodiment, the selected nickel foam template is 100 micrometers thick, has a pore density of 100 PPI (i.e., pores per inch), and an inherent volumetric porosity greater than 97%. This size nickel foam template is precisely cut and placed in the center of a quartz tube in the isothermal zone of a tubular chemical vapor deposition (CVD) furnace. Pretreatment is then performed under a reducing atmosphere of argon and hydrogen (precisely controlled volume ratio of 4:1, total flow rate of 205 sccm, i.e., standard cubic centimeters per minute), with the furnace temperature heated to 1000°C at a programmed rate of 20°C / min. After reaching the target temperature, the nickel foam template is annealed at this temperature for up to 30 minutes. The purpose of this annealing step is to eliminate the surface oxide layer and stress generated during the processing of nickel foam, and to repair its lattice defects, resulting in larger grains on its surface. This provides an ideal catalytic substrate for the subsequent uniform and large-area growth of high-quality graphene. After annealing, while maintaining a constant temperature of 1000°C, the hydrogen supply is cut off, and methane (CH4) gas at a flow rate of 10 sccm is immediately introduced as a carbon source. The catalytic growth reaction of graphene is carried out under atmospheric pressure for a precise duration of 15 minutes. At this high temperature, methane molecules are cracked under the catalysis of nickel, and carbon atoms are deposited and dissolved on the surface of nickel. When saturation is reached, carbon atoms precipitate on the surface of nickel and self-assemble into a six-membered ring graphene sp2 structure. The reaction time determines the number of graphene layers; under this parameter, high-quality single-layer or few-layer graphene can be obtained. After growth, the methane supply is immediately stopped, and the furnace and sample are allowed to cool naturally to room temperature under a pure argon atmosphere. This process yielded a composite nickel foam structure whose surface was completely covered by a layer of complete and uniform graphene film.

[0030] The second step of the method involves the removal of the sacrificial template. The graphene-coated composite nickel foam structure obtained in step one is completely immersed in a pre-prepared 3 mol / L hydrochloric acid aqueous solution. The entire system is placed in a constant-temperature water bath at 60°C for a chemical etching reaction lasting up to 8 hours. During this process, the chemically reactive metallic nickel reacts violently with hydrochloric acid (Ni + 2HCl → NiCl2 + H2↑), is completely corroded and dissolved in the aqueous solution, forming soluble nickel chloride. The chemically stable graphene, however, does not react under these conditions and is therefore completely preserved, forming a hollow, self-supporting, three-dimensional continuous porous graphene network framework that is completely identical in morphology to the original nickel foam template structure. To ensure product purity, after etching, the resulting graphene network framework is repeatedly and thoroughly rinsed with a large amount of deionized water. The pH of the washing solution is monitored using precision pH paper or a pH meter until it stabilizes at neutral 7, indicating that residual hydrochloric acid and nickel ions have been completely removed. Finally, to prevent the collapse of its fine three-dimensional porous structure while removing moisture, freeze-drying technology was employed. Specifically, the moist graphene framework was rapidly frozen to tens of degrees below zero Celsius, and then the solid ice was directly sublimated into water vapor and removed under high vacuum. This method avoids the structural damage caused by the surface tension of liquid water during conventional drying processes, resulting in a structurally intact and fluffy dried three-dimensional graphene network framework.

[0031] Step three of the method is the crucial surface functionalization of the graphene network framework. This step is subdivided into two sub-steps: surface activation and coupling agent grafting. First, surface activation is performed. The dried three-dimensional graphene network framework obtained in step two is placed flat on the sample stage of a plasma reactor chamber. It is then subjected to plasma treatment in an oxygen atmosphere. Specific process parameters are strictly controlled as follows: oxygen flow rate of 50 sccm, pressure within the reaction chamber maintained at 50 Pa by adjusting the vacuum pump speed and inlet flow rate, radio frequency (RF) power output set to 100 W, and treatment time accurate to 180 seconds. In this high-energy plasma environment, the graphene surface is etched and bombarded by highly reactive oxygen free radicals, introducing a large number of oxygen-containing functional groups, mainly hydroxyl (-OH) and carboxyl (-COOH), into its inherent defect sites and layer edges. These functional groups provide ample chemical reaction anchors for subsequent silane coupling agent grafting.

[0032] Next, chemical grafting with a coupling agent was performed. The surface-activated three-dimensional graphene network framework with active functional groups was immediately immersed in a pre-prepared coupling agent solution. This coupling agent solution was prepared by dissolving 2 parts by volume of 3-(methacryloyloxypropyl)trimethoxysilane (TMSPMA) in 98 parts by volume of anhydrous toluene and dispersing it uniformly in an ultrasonic bath. Under continuous protection of an inert gas (such as nitrogen), the reaction flask containing the graphene framework and coupling agent solution was heated to 80°C, and the grafting reaction was carried out at this temperature with magnetic stirring for up to 12 hours. During this process, the methoxysilyl groups in the TMSPMA molecules undergo hydrolysis and condensation reactions with the hydroxyl groups on the graphene surface, forming stable Si-OC covalent bonds, thereby firmly grafting the organic molecular chain segments with methacryloyloxy functional groups to every accessible surface of the graphene framework. After the reaction was completed, the functionalized graphene network framework was removed. To remove any physically adsorbed, non-chemically bonded TMSPMA molecules, it was cleaned multiple times in an ultrasonic cleaner using fresh toluene and ethanol solvents. Finally, the cleaned framework was dried in a vacuum oven at 60°C for 4 hours to obtain the final functionalized three-dimensional graphene network framework with polymeric active groups uniformly grafted onto its surface.

[0033] Step four of the method involves the preparation and impregnation of the adhesive monomer premix. Strictly following the aforementioned formula, 70 parts by weight of butyl acrylate, 28 parts by weight of methyl methacrylate, 1 part by weight of 1,6-hexanediol diacrylate, and 1 part by weight of 1-hydroxycyclohexylphenyl ketone are precisely weighed into a light-proof brown beaker. The mixture is then magnetically stirred until a clear, transparent, homogeneous adhesive monomer premix with low viscosity is formed. Subsequently, the first release layer (such as a PDMS-coated PET film) is laid flat on an absolutely clean, level glass substrate. The dried, fluffy functionalized three-dimensional graphene network skeleton obtained in step three is carefully and evenly placed in the center of the release layer. Next, the prepared adhesive monomer premix is ​​slowly and evenly added dropwise to the graphene network skeleton using a dropper until the premix completely impregnates and covers the entire skeleton. To achieve defect-free impregnation, the entire assembly is moved into a vacuum impregnation device (such as a vacuum drying oven or vacuum glove box), and the pressure inside the chamber is rapidly evacuated to a vacuum level of 100 Pa and maintained stably for 5 minutes. The purpose of this step is to completely remove air trapped within the complex porous structure of the graphene framework. Then, the air inlet valve is slowly opened, allowing the chamber to return to atmospheric pressure. During this process, the external atmospheric pressure forcefully compresses the low-viscosity monomer premix into every tiny pore of the graphene framework, ensuring complete impregnation without any residual air bubbles.

[0034] Step five of the method involves in-situ curing of the composite tape. After thorough impregnation, the second release layer is carefully and gently applied from one end to the other onto the graphene skeleton soaked in monomer premix, avoiding air bubbles, thus forming a standard "release layer-composite adhesive layer-release layer" sandwich structure. To precisely control the thickness of the final product, this sandwich structure assembly is immediately passed through a pair of precisely gap-controlled pressure rollers. The gap between the rollers is pre-calibrated and set to 105 micrometers, slightly larger than the original thickness of the graphene skeleton, to accommodate the filling adhesive. The pressing process not only extrudes very little excess premix but also ensures that the thickness of the final composite adhesive layer is uniform throughout the entire surface area. The pressed assembly is then conveyed to a UV curing device via a conveyor belt. Using a high-pressure mercury lamp with a center wavelength of 365 nm, the assembly is simultaneously irradiated from both top and bottom directions, with the total irradiation energy dose precisely controlled at 1000 mJ / cm². 2 Under strong ultraviolet light excitation, the photoinitiator 1-hydroxycyclohexylphenyl ketone in the premix rapidly decomposes to generate highly reactive free radicals, thereby initiating a rapid chain polymerization reaction of acrylate monomers within the system. During this polymerization network formation process, the methacryloyloxy functional groups grafted onto the graphene backbone surface act as comonomers, participating in the polymerization reaction through the opening of their double bonds. This forms stable C-C covalent bonds, firmly anchoring the growing polymer chains to the graphene backbone surface. Simultaneously, the reaction of the crosslinking agent 1,6-hexanediol diacrylate forms a three-dimensional polymer network structure with a certain strength. The entire polymerization reaction is completed within seconds to tens of seconds. After the polymerization reaction, a structurally stable, high-performance, ultra-thin, high-adhesion graphene thermally conductive double-sided adhesive tape is obtained. Finally, the large-format finished product is precisely cut and wound as needed, completing all preparation steps. Detailed Implementation

[0035] This embodiment aims to specifically demonstrate the detailed process of preparing an ultrathin, high-viscosity graphene thermally conductive double-sided adhesive tape according to the method of the present invention.

[0036] (1) Preparation of three-dimensional graphene network framework: A commercially available nickel foam with dimensions of 20cm x 20cm, a thickness of 100μm, a pore density of 100PPI, and a porosity greater than 97% was selected as a sacrificial template. It was placed in the isothermal zone of a CVD tubular furnace quartz tube. Under a mixed atmosphere of 200sccm argon and 5sccm hydrogen, the temperature was increased to 1000℃ at a rate of 20℃ / min and held for 30 minutes for annealing. Subsequently, the hydrogen supply was stopped, and 10sccm of methane gas was introduced. The reaction was carried out at 1000℃ and atmospheric pressure for 15 minutes. After the reaction, the methane supply was stopped, and the mixture was naturally cooled to room temperature in an argon atmosphere to obtain graphene-coated nickel foam.

[0037] (2) Template Removal and Drying: The above sample was immersed in a 3 mol / L hydrochloric acid solution and reacted in a 60°C water bath for 8 hours until the nickel foam was completely dissolved. The black self-supporting three-dimensional graphene network skeleton was removed and repeatedly rinsed with deionized water until the pH of the washing solution reached 7. Subsequently, it was freeze-dried for 24 hours to obtain a dry and fluffy graphene skeleton. After weighing and volume calculation, its target mass fraction in the final composite adhesive layer was 3.0 wt%.

[0038] (3) Surface functionalization: The dried graphene framework was placed in a plasma reactor and treated for 180 seconds at an oxygen flow rate of 50 sccm, a pressure of 50 Pa, and a radio frequency power of 100 W. It was then immersed in a solution prepared with 2 mL of TMSPMA and 98 mL of anhydrous toluene and reacted at 80 °C for 12 hours under nitrogen protection. After the reaction, it was ultrasonically cleaned three times each with toluene and ethanol, and then dried in a vacuum oven at 60 °C for 4 hours.

[0039] (4) Impregnation and Curing: Under light-protected conditions, 70g of butyl acrylate, 28g of methyl methacrylate, 1g of 1,6-hexanediol diacrylate, and 1g of 1-hydroxycyclohexylphenyl ketone were mixed evenly to prepare a monomer premix. A 50-micron-thick PET release film (single-sided PDMS coating) was placed on a glass plate, and the functionalized graphene framework was laid flat on it. The monomer premix was added dropwise until completely immersed. The component was placed in a vacuum chamber, evacuated to 100 Pa and maintained for 5 minutes, and then slowly restored to normal pressure. Afterward, another identical PET release film was covered and pressed together using rollers with a gap of 105 microns. Finally, this sandwich structure component was subjected to a UV curing machine with a power of 2kW and a center wavelength of 365nm at a specific speed to allow it to receive 1000mJ / cm. 2 The irradiation dose was used to cure both sides, and finally a double-sided adhesive tape with a composite adhesive layer thickness of 100 micrometers was obtained.

[0040] Comparative Example 1 This comparative example aims to prepare a thermally conductive double-sided tape with the same graphene content and thickness using a traditional physical blending method, for performance comparison.

[0041] (1) Adhesive preparation: 70g butyl acrylate, 28g methyl methacrylate, 1g 1,6-hexanediol diacrylate and 0.5g azobisisobutyronitrile (AIBN) were dissolved in 200g ethyl acetate and subjected to solution polymerization at 75℃ to obtain an acrylic pressure-sensitive adhesive solution with a solid content of about 33%.

[0042] (2) Physical blending: Take 300g of the acrylic pressure-sensitive adhesive solution prepared above (containing approximately 100g of polymer). Take another 3.09g of commercial graphene nanosheets (GNP, average sheet diameter 5 μm, thickness <10 nm). Add the GNP to the pressure-sensitive adhesive solution and stir at 8000 rpm for 2 hours using a high-speed shear disperser, followed by treatment with a probe-type ultrasonic processor for 1 hour to disperse it as evenly as possible, resulting in a black thermally conductive adhesive.

[0043] (3) Coating and Drying: The above thermally conductive adhesive is evenly coated onto a 50-micron-thick PET release film using a doctor blade coater. The coated release film is then placed in an oven at 100°C for 30 minutes to completely remove the ethyl acetate solvent. The wet film coating thickness is controlled so that the dried adhesive layer thickness is 100 microns.

[0044] (4) Lamination: After the adhesive layer cools to room temperature, another 50-micron thick PET release film is laminated onto the surface of the adhesive layer to obtain the final double-sided tape product.

[0045] Performance testing and data comparison The performance of the samples prepared in Example 1 and Comparative Example 1 was tested, and the test standards and results are summarized in the table below.

[0046] The data comparison in the table above clearly shows that the ultrathin, high-viscosity graphene thermally conductive double-sided adhesive tape prepared in Example 1, compared with the sample of Comparative Example 1 prepared using the traditional physical blending method, exhibits fundamental differences in its core performance, even with identical graphene filler content and final product thickness. Specifically, the vertical thermal conductivity of the product in Example 1 reached 5.2 W / m·K, which is 6.5 times that of the product in Comparative Example 1. This strongly demonstrates that the scheme of pre-constructing a three-dimensional continuous graphene network framework as a thermally conductive pathway is far superior in thermal conductivity to the randomly dispersed filler percolation network. Furthermore, the key adhesive performance indicators of Example 1, such as 180° peel strength and holding power, are not only not sacrificed due to the presence of thermal conductivity, but are significantly better than those of Comparative Example 1. This is attributed to the fact that in the structure of this invention, the dominant position and continuity of the polymer adhesive matrix are maintained, and the overall cohesive strength is improved through the enhanced composite structure formed by chemical bonding with the graphene framework. In Comparative Example 1, even with a low addition of only 3.0 wt%, the dispersed graphene sheets still disrupted the continuity of the polymer matrix, creating stress concentration points and thus weakening the adhesive properties. Furthermore, the significant difference in volume resistivity confirmed the formation of a through-conductive network in Example 1, while in Comparative Example 1, the graphene sheets failed to form effective contact. In summary, the technical solution provided by this invention successfully resolves the inherent contradiction between thermal conductivity and adhesive properties, achieving a high level of synergy between the two.

Claims

1. An ultrathin, high-adhesion graphene thermally conductive double-sided adhesive tape, comprising a composite adhesive layer, characterized in that, The composite adhesive layer comprises the following components: a three-dimensional continuous porous graphene network framework macroscopically penetrating the entire three-dimensional volume of the composite adhesive layer, forming a physically continuous pathway for heat conduction; a surface-functionalized interface layer chemically bonded to the surface of the three-dimensional continuous porous graphene network framework, serving as a chemical bridge connecting the graphene network framework and the polymer adhesive matrix; and a polymer adhesive matrix filling the internal pores of the three-dimensional continuous porous graphene network framework coated with the surface-functionalized interface layer, wherein the polymer adhesive matrix and the surface-functionalized interface layer are chemically bonded, and the polymer adhesive matrix is ​​formed by in-situ polymerization of a premix containing at least one acrylate monomer within the graphene network framework.

2. The ultra-thin, high-adhesion graphene thermally conductive double-sided tape according to claim 1, characterized in that, The three-dimensional continuous porous graphene network skeleton has a volume porosity of more than 95%, and the average pore size of its internal pores ranges from 50 micrometers to 300 micrometers; furthermore, the mass fraction of the three-dimensional continuous porous graphene network skeleton in the composite adhesive layer is less than 5%.

3. The ultra-thin, high-adhesion graphene thermally conductive double-sided tape according to claim 1, characterized in that, The surface-functionalized interface layer is a product formed by a chemical reaction between a silane coupling agent and a surface-activated graphene surface with active sites. The molecular structure of the silane coupling agent contains at least one first functional group that can react with the active sites on the graphene surface to form a stable covalent bond, and the other end of its molecular structure contains at least one second active functional group that can participate in the in-situ polymerization reaction of the polymer adhesive matrix.

4. The ultra-thin, high-adhesion graphene thermally conductive double-sided tape according to claim 3, characterized in that, The active sites on the graphene surface are hydroxyl or carboxyl groups; the first functional group is a hydrolyzable silane group, which reacts with the hydroxyl group to form a siloxane bond; the second active functional group is methacryloyloxy; and the silane coupling agent is 3-(methacryloyloxypropyl)trimethoxysilane 1.

5. The ultra-thin, high-adhesion graphene thermally conductive double-sided tape according to claim 1, characterized in that, The polymer adhesive matrix is ​​formed by in-situ free radical polymerization of a premix containing at least two acrylate monomers within the graphene network framework. The polymer adhesive matrix and the surface functionalized interface layer are covalently connected through a copolymerization reaction involving the second active functional group.

6. The ultra-thin, high-adhesion graphene thermally conductive double-sided tape according to claim 5, characterized in that, The polymeric adhesive matrix is ​​prepared by the following parts by weight of raw materials through the in-situ polymerization reaction: 70 parts by weight of butyl acrylate, as the main monomer that imparts flexibility and initial tack to the adhesive; 28 parts by weight of methyl methacrylate, as the comonomer that improves the cohesive strength and glass transition temperature of the adhesive; 1 part by weight of 1,6-hexanediol diacrylate, as a crosslinking agent, used to form a network structure during polymerization to improve holding power and temperature resistance; and 1 part by weight of 1-hydroxycyclohexylphenyl ketone, as a photoinitiator, used to initiate the free radical polymerization reaction under ultraviolet light irradiation of a specific wavelength.

7. The ultra-thin, high-adhesion graphene thermally conductive double-sided adhesive tape according to any one of claims 1 to 6, characterized in that, It also includes a first release layer and a second release layer symmetrically disposed on the two main surfaces of the composite adhesive layer.

8. The ultra-thin, high-adhesion graphene thermally conductive double-sided tape according to claim 7, characterized in that, Both the first and second release layers are polyethylene terephthalate films, with a polydimethylsiloxane release agent coating applied to the side of the release layer facing the composite adhesive layer. Specifically, the polyethylene terephthalate film has a thickness of 50 micrometers, the polydimethylsiloxane release agent coating has a thickness of 1 micrometer, and the peel force between the release agent coating and the composite adhesive layer is 0.05 N / 25 mm under a 180-degree peel test.

9. The ultra-thin, high-viscosity graphene thermally conductive double-sided tape according to claim 7 or 8, characterized in that, To impart antistatic properties to the double-sided tape, the outer surface of the first release layer that does not contact the composite adhesive layer is coated with a conductive coating; the surface resistivity of the conductive coating is 10^6 to 10^9 Ω / sq, and the conductive coating is a conductive polymer coating based on poly(3,4-ethylenedioxythiophene):polystyrene sulfonic acid.

10. A method for preparing an ultrathin, high-viscosity graphene thermally conductive double-sided adhesive tape as described in any one of claims 1 to 9, characterized in that, It includes the following steps: Step 1: Construction of a three-dimensional continuous porous graphene network framework. This step specifically includes: providing a three-dimensional mesh porous metal as a sacrificial template; growing a graphene layer on the entire surface of the sacrificial template using chemical vapor deposition to obtain a graphene-coated composite structure; and completely removing the sacrificial template by chemical etching, followed by cleaning and drying to obtain the three-dimensional continuous porous graphene network framework. Step 2: Surface functionalization of the graphene network framework. This step specifically includes: surface activation treatment of the graphene network framework to introduce oxygen-containing functional groups as active reaction sites on its surface; and reacting the activated graphene network framework with a silane coupling agent having a first functional group and a second active functional group at each end of its molecule, such that the silane coupling agent forms a covalent bond with the active reaction site through the first functional group, thereby grafting the second active functional group onto the surface of the graphene network framework. Step 3: Preparation and impregnation of the adhesive monomer premix, specifically including: uniformly mixing at least one acrylate monomer, crosslinking agent, and initiator to prepare an adhesive monomer premix; and, using a vacuum-assisted method, completely and bubble-free impregnating and filling the internal pores of the functionalized graphene network skeleton with the adhesive monomer premix; Step 4: In-situ curing and molding of the composite tape, specifically including: covering the upper and lower main surfaces of the graphene skeleton impregnated with the monomer premix with release layers to form a sandwich structure component; and, by applying ultraviolet light irradiation or heating, initiating an in-situ polymerization reaction of the monomer premix inside the graphene network skeleton. During this polymerization process, the second active functional group grafted onto the surface of the graphene skeleton participates in the polymerization as a comonomer, thereby forming a chemical bond between the polymer adhesive matrix and the graphene network skeleton, and finally curing and molding into the double-sided tape.

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