Epoxy composition capable of being used for bonding camera module support and preparation method of epoxy composition

Abstract

The invention relates to the technical field of structural adhesives, in particular to an epoxy composition capable of being used for bonding a camera module support and a preparation method of the epoxy composition, and the epoxy composition comprises the following components in parts by weight: 7-10 parts of epoxy resin; 20-25 parts of flexible epoxy resin; 5-10 parts of a core-shell epoxy resin toughening agent; 20-25 parts of a compound filler; 30 to 31 parts of organic hydrazide; and 8-9 parts of a modified amine adduct. The flexible epoxy resin has at least one structural characteristic of a long-chain polyether structure and an indene structure. The compound filler comprises calcium carbonate and silicon dioxide. The epoxy composition capable of being used for bonding the camera module support has the advantages of low precipitation, low curing shrinkage, high bonding strength, low modulus and excellent falling resistance, the reliability of the camera module support structure can be remarkably improved, and the epoxy composition is suitable for application environments of various miniature high-performance camera modules.

Description

Technical Field

[0001] This invention relates to an epoxy composition that can be used for bonding camera module brackets and its preparation method, belonging to the field of structural adhesive technology. Background Technology

[0002] The digital age is rapidly evolving, encompassing a wide range of applications from smart terminals to new energy vehicles, bringing about a revolution in camera technology. This revolution is not only driven by breakthroughs in sensors and processing algorithms, but also closely linked to the application of materials supporting these technologies, with the assembly process of camera modules being crucial. The miniaturization and increasing complexity of camera module structures lead to a decrease in the mechanical strength of the lens bracket, making it difficult to withstand the stress generated by mechanical vibrations during operation, thus affecting the camera's operational stability. To address this issue, the industry widely adopts a technique of fixing the lens bracket with structural adhesive, effectively improving the robustness of the lens bracket structure and enhancing the camera's operational stability.

[0003] Structural adhesives for lens mounts are widely used in the manufacturing of camera modules for smartphones, tablets, laptops, automotive electronics, and many other fields. However, as the performance of camera modules continues to improve, the performance requirements for structural adhesives are also increasing. Currently, existing structural adhesives typically experience significant volume shrinkage during thermosetting. This shrinkage introduces additional stress between the lens and the mount, leading to defects such as lens warping and cracking, thus affecting the camera's operational stability. Existing structural adhesives also suffer from high elastic modulus and poor flexibility, making it difficult to effectively buffer mechanical stress. Furthermore, existing structural adhesives are prone to exudation, which can easily cause chemical contamination of the lens within a confined space, affecting the camera's resolution.

[0004] Therefore, there is an urgent need to develop a structural adhesive material to solve a series of problems caused by high curing shrinkage, high elastic modulus, poor flexibility, and large exudation in the existing technology, thereby improving the working stability and image high definition of the camera. Summary of the Invention

[0005] This invention addresses the technical problems of high exudation and high curing shrinkage of existing structural adhesives by providing an epoxy composition and its preparation method for bonding camera module brackets. The epoxy composition features low exudation, low curing shrinkage, high bonding strength, low modulus, and excellent drop resistance, which can significantly improve the reliability of camera module bracket structures.

[0006] The technical solution of the present invention to solve the above-mentioned technical problems is as follows: An epoxy composition that can be used for bonding camera module brackets, wherein the epoxy composition comprises the following components in parts by weight: 7-10 parts epoxy resin; 20-25 parts of flexible epoxy resin; 5-10 parts of core-shell epoxy resin toughening agent; 20-25 parts of compound filler; 30-31 parts of organic hydrazide; 8-9 parts of modified amine adduct.

[0007] Based on the above technical solution, the present invention can also be improved as follows: Furthermore, the flexible epoxy resin has at least one structural feature of a long-chain polyether structure and a dihydroindene structure.

[0008] Furthermore, the flexible epoxy resin has the following structure: ; Among them, the long-chain polyether and dihydroindene structure in the molecular structure have good low shrinkage and flexibility, and the epoxy group in the molecular structure makes it highly reactive.

[0009] Furthermore, the composite filler includes calcium carbonate and silicon dioxide.

[0010] Furthermore, the preparation method of the composite filler is as follows: Calcium carbonate and nano-silica were dispersed in ethanol, a coupling agent was added, the mixture was stirred thoroughly, and then allowed to stand. The supernatant was removed, and the resulting modified powder was dried to obtain the composite filler.

[0011] Furthermore, in the preparation of the compound filler, the amount of coupling agent is 1wt%-3wt% of the total mass of calcium carbonate and nano silica, and the mass ratio of calcium carbonate to nano silica is (9-11):1; the maximum particle size of calcium carbonate is 20-25μm, the average particle size is 10-12μm, and the maximum particle size of nano silica is 0.4-0.5μm, the average particle size is 0.05-0.1μm.

[0012] Furthermore, the organic hydrazide is a nitrogen-containing heterocyclic dihydrazide compound.

[0013] Furthermore, the method for preparing the organic hydrazide is as follows: Under inert gas protection, 5-isopropylhydantoin and methyl acrylate were added to a reactor, along with an alkaline catalyst and a polymerization inhibitor hydroquinone. The reaction was carried out under reflux conditions. After the reaction was completed, excess methyl acrylate was removed to obtain an intermediate, which is the 2:1 molar addition product of 5-isopropylhydantoin and methyl acrylate. Under inert gas protection, the intermediate is dissolved in ethanol, and an ethanol solution of hydrazine hydrate is slowly added. The mixture is refluxed to carry out the reaction. After the reaction is completed, the organic hydrazide is obtained by post-treatment and purification.

[0014] Furthermore, the organic hydrazide has the following structure: .

[0015] This invention also discloses a method for preparing an epoxy composition that can be used for bonding camera module brackets, the preparation method comprising the following steps: Weigh the required weights of epoxy resin, flexible epoxy resin, core-shell epoxy resin toughening agent, compound filler, and organic hydrazide, mix them thoroughly and evenly, add the required weights of modified amine adduct, and mix thoroughly and evenly under vacuum conditions to obtain the epoxy composition that can be used for bonding camera module brackets.

[0016] The beneficial effects of this invention are: This invention provides an epoxy composition suitable for bonding camera module brackets. The material uses flexible epoxy resin as the main resin, which has good flexibility and low curing shrinkage, and can effectively reduce problems such as lens warping and cracking caused by large curing shrinkage.

[0017] This invention uses compound fillers and a coupling agent modification process on the filler surface to significantly improve the compatibility and adhesion strength between inorganic fillers and organic resin matrix. By utilizing the complementary effect of micron-sized and nano-sized fillers in terms of particle size, the density and dimensional stability of the composition are effectively improved, and the curing shrinkage rate and precipitation tendency are significantly reduced.

[0018] This invention utilizes a self-synthesized organic hydrazide. By introducing the synergistic effect of rigid hydantoin heterocycles and flexible alkyl segments, the composition significantly improves toughness and drop resistance while maintaining high adhesive strength and thermal stability. The organic hydrazide component with the specific structure exhibits good reactivity and stable molecular structure, effectively reducing the composition's precipitation tendency and improving its curing reaction efficiency, thus meeting the high-performance material requirements of the high-performance camera module field.

[0019] In summary, the epoxy composition provided by this invention for bonding camera module brackets has the advantages of low exudation, low curing shrinkage, high bonding strength, low modulus, and excellent drop resistance, which can significantly improve the reliability of camera module bracket structures and is suitable for various application environments of miniature high-performance camera modules.

[0020] Based on this invention, the material system can be adapted to meet specific application requirements, and all such adjustments fall within the scope of this invention. For example, adding fluorescent agents can impart fluorescence detection capabilities to the material, facilitating quality monitoring during the encapsulation process; introducing pigments such as color pastes or carbon black can adjust the material's appearance color to meet the identification or aesthetic requirements of different application scenarios. Furthermore, adding functional additives such as antioxidants, hydrolysis inhibitors, or UV absorbers can significantly improve the material's heat aging resistance, damp heat stability, and UV degradation resistance, enabling it to adapt to harsher environmental conditions and extend the lifespan of the support structure. All of the above adjustments can be implemented without departing from the core concept of this invention and are covered within the scope of protection of this invention. Detailed Implementation

[0021] The specific embodiments of the present invention will be described in detail below. The present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used is for describing particular embodiments only and is not intended to limit the invention.

[0023] An epoxy composition for bonding camera module brackets, comprising, by weight, the following components: 7-10 parts epoxy resin; 20-25 parts flexible epoxy resin; 5-10 parts core-shell epoxy resin toughening agent; 20-25 parts compound filler; 30-31 parts organic hydrazide; and 8-9 parts modified amine adduct.

[0024] Specifically, the flexible epoxy resin has at least one structural feature of a long-chain polyether structure and a dihydroindene structure.

[0025] Specifically, the flexible epoxy resin has the following structure: ; Among them, the long-chain polyether and dihydroindene structure in the molecular structure have good low shrinkage and flexibility, and the epoxy group in the molecular structure makes it highly reactive.

[0026] Specifically, the composite filler includes calcium carbonate and silicon dioxide.

[0027] Specifically, the preparation method of the composite filler is as follows: Calcium carbonate and nano-silica were dispersed in ethanol, a coupling agent was added, the mixture was stirred thoroughly, and then allowed to stand. The supernatant was removed, and the resulting modified powder was dried to obtain the composite filler.

[0028] More specifically, calcium carbonate and nano-silica are dispersed in ethanol, a coupling agent is added, and the mixture is stirred thoroughly for 1-2 hours. Then, it is allowed to stand for 25-35 minutes, the supernatant is removed, and the resulting modified powder is dried for 2-3 hours to obtain the composite filler.

[0029] Specifically, in the preparation of the compound filler, the amount of coupling agent is 1wt% to 3wt% of the total mass of calcium carbonate and nano silica, and the mass ratio of calcium carbonate to nano silica is (9-11):1; the maximum particle size of calcium carbonate is 20-25μm, the average particle size is 10-12μm, and the maximum particle size of nano silica is 0.4-0.5μm, the average particle size is 0.05-0.1μm.

[0030] More specifically, in the preparation of the compound filler in this embodiment of the invention, the mass ratio of calcium carbonate to nano-silica is 10:1; the maximum particle size of calcium carbonate is 25 μm and the average particle size is 12 μm, and the maximum particle size of nano-silica is 0.5 μm and the average particle size is 0.1 μm.

[0031] More specifically, the coupling agent used in the embodiments of the present invention is ANJEKA 6910A, a copolymer containing acidic groups.

[0032] Specifically, the organic hydrazide is a nitrogen-containing heterocyclic dihydrazide compound.

[0033] Specifically, the preparation method of the organic hydrazide is as follows: Under inert gas protection, 5-isopropylhydantoin and methyl acrylate were added to a reactor, along with an alkaline catalyst and a polymerization inhibitor hydroquinone. The reaction was carried out under reflux conditions. After the reaction was completed, excess methyl acrylate was removed to obtain an intermediate, which is the 2:1 molar addition product of 5-isopropylhydantoin and methyl acrylate. Under inert gas protection, the intermediate is dissolved in ethanol, and an ethanol solution of hydrazine hydrate is slowly added. The mixture is refluxed to carry out the reaction. After the reaction is completed, the organic hydrazide is obtained by post-treatment and purification.

[0034] Specifically, the organic hydrazide has the following structure: .

[0035] The reaction formula for the preparation of organic acylhydrazides is as follows: .

[0036] 5-Isopropylhydantoin and methyl acrylate undergo a bisMichael addition reaction under the action of an alkaline catalyst. This diester intermediate undergoes ammonolysis with excess hydrazine hydrate, converting all ester groups to hydrazide groups to form an organic hydrazide. The dihydrazide functional groups at both ends of the organic hydrazide molecule combine reactivity with low curing shrinkage; the hydantoin heterocyclic structure provides high adhesive strength and thermal stability; and the flexible propyl chain and hydrophobic isopropyl side chain exhibit good drop resistance.

[0037] A method for preparing an epoxy composition that can be used for bonding camera module brackets, the method comprising the following steps: Weigh the required weights of epoxy resin, flexible epoxy resin, core-shell epoxy resin toughening agent, compound filler, and organic hydrazide, mix them thoroughly and evenly, add the required weights of modified amine adduct, and mix thoroughly and evenly under vacuum conditions to obtain the epoxy composition that can be used for bonding camera module brackets.

[0038] The specific types of raw materials used in the embodiments of this invention are as follows (this does not constitute a limitation on the technical solution of this invention): The epoxy resin is EXA-850CRP from DIC Corporation of Japan; The flexible epoxy resin is EXA-4850 from DIC Corporation of Japan; The rubber-modified epoxy resin is 861340 produced by Shenzhen Jiadida Chemical Co., Ltd. The core-shell epoxy toughening agent is MX-125 manufactured by Kaneka Corporation of Japan. The calcium carbonate mentioned is WHISCAL A produced by Maruo Co., Ltd. of Japan. The nano-silica is YA050C manufactured by Yatsuma Corporation of Japan; The coupling agent is ANJEKA 6910A manufactured by Ezhou Anjikang Technology Co., Ltd. The modified amine adduct is MY-24 from Ajinomoto Co., Ltd., Japan.

[0039] Example 1 Preparation of composite fillers: 200g of calcium carbonate and 20g of nano-silica were dispersed in a beaker containing ethanol, and 3g of coupling agent (ANJEKA 6910A) was added. The mixture was stirred for 1 hour, allowed to stand for 30 minutes, and the supernatant was removed. The resulting modified powder was dried at 75°C for 3 hours to obtain the composite filler.

[0040] Example 2 Synthesis of organic acylhydrazides: Under nitrogen protection, 142.2 g of 5-isopropylhydantoin and 344.4 g of methyl acrylate were added to a 2000 mL three-necked flask, along with 5 g of potassium hydroxide (an alkaline catalyst) and 5 g of hydroquinone (a polymerization inhibitor). The mixture was heated to reflux and stirred for 3 hours. After the reaction was complete, excess methyl acrylate was removed by vacuum distillation to obtain a 2:1 molar addition product of 5-isopropylhydantoin and methyl acrylate.

[0041] Under nitrogen protection, 600 mL of ethanol was added to a three-necked flask. Then, 600 mL of a 5 mol / L hydrazine hydrate ethanol solution was added dropwise to the flask using a constant-pressure dropping funnel. The mixture was heated to reflux and stirred for 4 hours. After the reaction was complete, the mixture was distilled under reduced pressure and dried to obtain the organic hydrazide.

[0042] Example 3 Preparation of an epoxy composition for bonding camera module brackets: The epoxy composition described in this embodiment comprises the following components in parts by weight: Epoxy resin (EXA-850CRP): 7 parts; Flexible epoxy resin (EXA-4850): 25 parts; Core-shell epoxy resin toughening agent (MX-125): 5 parts; Composite filler (prepared in Example 1): 25 parts; Organic hydrazide (prepared in Example 2): 30 parts; Modified amine adduct (MY-24): 8 parts.

[0043] The preparation method is as follows: according to the above formula, weigh the required weight of epoxy resin, flexible epoxy resin, core-shell epoxy resin toughening agent, compound filler, and organic hydrazide. After stirring thoroughly, add the required weight of modified amine adduct. Stir thoroughly under vacuum conditions to obtain an epoxy composition that can be used for bonding camera module brackets.

[0044] Example 4 Preparation of an epoxy composition for bonding camera module brackets: The epoxy composition described in this embodiment comprises the following components in parts by weight: Epoxy resin (EXA-850CRP): 10 parts; Flexible epoxy resin (EXA-4850): 20 parts; Core-shell epoxy resin toughening agent (MX-125): 10 parts; Composite filler (prepared in Example 1): 20 parts; Organic hydrazides (prepared in Example 2): 31 parts; Modified amine adduct (MY-24): 9 parts.

[0045] The preparation method is as follows: according to the above formula, weigh the required weight of epoxy resin, flexible epoxy resin, core-shell epoxy resin toughening agent, compound filler, and organic hydrazide. After stirring thoroughly, add the required weight of modified amine adduct. Stir thoroughly under vacuum conditions to obtain an epoxy composition that can be used for bonding camera module brackets.

[0046] Example 5 Preparation of an epoxy composition for bonding camera module brackets: The epoxy composition described in this embodiment comprises the following components in parts by weight: Epoxy resin (EXA-850CRP): 8 parts; Flexible epoxy resin (EXA-4850): 22 parts; Core-shell epoxy resin toughening agent (MX-125): 8 parts; Composite filler (prepared in Example 1): 24 parts; Organic hydrazide (prepared in Example 2): 30 parts; Modified amine adduct (MY-24): 8 parts.

[0047] The preparation method is as follows: according to the above formula, weigh the required weight of epoxy resin, flexible epoxy resin, core-shell epoxy resin toughening agent, compound filler, and organic hydrazide. After stirring thoroughly, add the required weight of modified amine adduct. Stir thoroughly under vacuum conditions to obtain an epoxy composition that can be used for bonding camera module brackets.

[0048] Comparative Example 1 The epoxy composition was prepared using the same method as in Example 3, except that the formulation of Comparative Example 1 did not use flexible epoxy resin (EXA-4850), but instead used the same amount of commercially available rubber-modified epoxy resin, as detailed below: The epoxy composition described in this comparative example comprises the following components in parts by weight: Epoxy resin (EXA-850CRP): 7 parts; Rubber-modified epoxy resin (861340): 25 parts; Core-shell epoxy resin toughening agent (MX-125): 5 parts; Composite filler (prepared in Example 1): 25 parts; Organic hydrazide (prepared in Example 2): 30 parts; Modified amine adduct (MY-24): 8 parts.

[0049] The preparation method is as follows: according to the above formula, weigh the required weight of epoxy resin, rubber-modified epoxy resin, core-shell epoxy resin toughening agent, compound filler, and organic hydrazide. After thorough stirring, add the required weight of modified amine adduct. Stir thoroughly under vacuum conditions to obtain the epoxy composition.

[0050] Comparative Example 2 The epoxy composition was prepared using the same method as in Example 3, except that the formulation of Comparative Example 2 did not use the compound filler of the present invention, but instead used a single filler, as detailed below: The epoxy composition described in this comparative example comprises the following components in parts by weight: Epoxy resin (EXA-850CRP): 7 parts; Flexible epoxy resin (EXA-4850): 25 parts; Core-shell epoxy resin toughening agent (MX-125): 5 parts; Filler (WHISCAL A): 25 parts; Organic hydrazide (prepared in Example 2): 30 parts; Modified amine adduct (MY-24): 8 parts.

[0051] The preparation method is as follows: according to the above formula, weigh the required weight of epoxy resin, flexible epoxy resin, core-shell epoxy resin toughening agent, filler, and organic hydrazide. After stirring thoroughly, add the required weight of modified amine adduct. Stir thoroughly under vacuum conditions to obtain the epoxy composition.

[0052] Comparative Example 3 The epoxy composition was prepared using the same method as in Example 3, except that the formulation of Comparative Example 3 did not use the organic hydrazide of the present invention, but instead used a conventional commercially available hydrazide, as detailed below: The epoxy composition described in this comparative example comprises the following components in parts by weight: Epoxy resin (EXA-850CRP): 7 parts; Flexible epoxy resin (EXA-4850): 25 parts; Core-shell epoxy resin toughening agent (MX-125): 5 parts; Composite filler (prepared in Example 1): 25 parts; Organic hydrazide (candihydrazide): 30 parts; Modified amine adduct (MY-24): 8 parts.

[0053] The preparation method is as follows: according to the above formula, weigh the required weight of epoxy resin, flexible epoxy resin, core-shell epoxy resin toughening agent, compound filler, and organic hydrazide. After stirring thoroughly, add the required weight of modified amine adduct. Stir thoroughly under vacuum conditions to obtain an epoxy composition that can be used for bonding camera module brackets.

[0054] Comparative Example 4 The epoxy composition was prepared using the same method as in Example 4, except that the formulation of Comparative Example 4 did not use the flexible epoxy resin (EXA-4850), the compound filler of the present invention, or the organic hydrazide of the present invention. Instead, it used the same amount of commercially available rubber-modified epoxy resin, a single filler, and a conventional commercially available hydrazide; specifically as follows: The epoxy composition described in this comparative example comprises the following components in parts by weight: Epoxy resin (EXA-850CRP): 7 parts; Rubber-modified epoxy resin (861340): 25 parts; Core-shell epoxy resin toughening agent (MX-125): 5 parts; Filler (WHISCAL A): 25 parts; Organic hydrazide (candihydrazide): 30 parts; Modified amine adduct (MY-24): 8 parts.

[0055] The preparation method is as follows: according to the above formula, weigh the required weight of epoxy resin, rubber-modified epoxy resin, core-shell epoxy resin toughening agent, filler, and organic hydrazide. After stirring thoroughly, add the required weight of modified amine adduct. Stir thoroughly under vacuum conditions to obtain the epoxy composition.

[0056] The epoxy compositions obtained in Examples 3-5 and Comparative Examples 1-4 were subjected to performance tests, and the results are shown in Table 1. The test methods involved are as follows: Exudation test: Place a rectangular steel mesh with dimensions of 45mm × 35mm × 0.2mm in the center of the filter paper, apply adhesive (epoxy composition) to one side of the steel mesh and smooth it with a scraper; heat to cure (heating conditions are 110℃ / 30min), remove and cool to room temperature, and measure the length of the diffusion layer of the filter paper.

[0057] Thermosetting shrinkage test: Place a rectangular steel mesh with dimensions of 45mm × 35mm × 0.2mm in the center of the filter paper, apply adhesive (epoxy composition) to one side of the steel mesh and smooth it with a scraper; heat to cure (heating conditions are 110℃ / 30min), remove and cool to room temperature, and measure the minimum curl of the filter paper.

[0058] Adhesion test: Glass was bonded to a PCB substrate with an epoxy composition, and the thrust was tested at 25°C.

[0059] Modulus test: The sample of epoxy composition after being cured by heating is placed in a dynamic thermomechanical analyzer to test its modulus.

[0060] Drop test: The simulated sample of the PCB substrate and glass bonded with epoxy composition was placed in a 1.8m automatic drop tester for 50 cycles and observed for delamination or cracking.

[0061] Table 1. Component ratios and performance test results of the examples and comparative examples. Note: The closer the curl is to the diameter of the circular filter paper (90mm), the less shrinkage there is.

[0062] As can be seen from the test results in Table 1 above, the epoxy composition of the present invention, which can be used for bonding camera module brackets, has the advantages and characteristics of low exudation, low curing shrinkage, high bonding strength, low modulus, and good drop resistance.

[0063] Comparative Example 1 did not use the flexible epoxy resin of the present invention, but used a commercially available rubber-modified epoxy resin. The low exudation was acceptable, but the thermosetting shrinkage was large, the adhesion was low, the modulus was high, and the drop resistance was poor.

[0064] Comparative Example 2 did not use the compound filler of the present invention, but used a single filler. The thermosetting shrinkage, adhesion and modulus were acceptable, but the precipitation was large and the drop resistance was poor.

[0065] Comparative Example 3 did not use the organic hydrazide of the present invention, but used a commercially available hydrazide, which resulted in large precipitation and large thermosetting shrinkage; although the modulus was acceptable, the poor adhesion led to poor drop resistance.

[0066] Comparative Example 4 did not use the flexible epoxy resin, compound filler, and organic hydrazide of the present invention, resulting in large precipitation, poor adhesion, large thermosetting shrinkage, high modulus, and poor drop resistance.

[0067] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are exhaustively listed. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0068] For those skilled in the art, various modifications and improvements can be made without departing from the concept of the present invention, and these modifications and improvements are all within the scope of protection of the present invention. The scope of protection of the present invention is defined by the appended claims.

Claims

1. An epoxy composition for bonding camera module brackets, characterized in that, The epoxy composition comprises the following components in parts by weight: 7-10 parts epoxy resin; 20-25 parts of flexible epoxy resin; 5-10 parts of core-shell epoxy resin toughening agent; 20-25 parts of compound filler; 30-31 parts of organic hydrazide; 8-9 parts of modified amine adduct.

2. The epoxy composition for bonding camera module brackets according to claim 1, characterized in that, The flexible epoxy resin has at least one structural feature: a long-chain polyether structure and a dihydroindene structure.

3. The epoxy composition for bonding camera module brackets according to claim 2, characterized in that, The flexible epoxy resin has the following structure: 。 4. The epoxy composition for bonding camera module brackets according to claim 1, characterized in that, The composite filler includes calcium carbonate and silicon dioxide.

5. The epoxy composition for bonding camera module brackets according to claim 4, characterized in that, The preparation method of the composite filler is as follows: Calcium carbonate and nano-silica were dispersed in ethanol, a coupling agent was added, the mixture was stirred thoroughly, and then allowed to stand. The supernatant was removed, and the resulting modified powder was dried to obtain the composite filler.

6. The epoxy composition for bonding camera module brackets according to claim 5, characterized in that, In the preparation of the compound filler, the amount of coupling agent is 1wt%-3wt% of the total mass of calcium carbonate and nano silica, and the mass ratio of calcium carbonate to nano silica is (9-11):1; the maximum particle size of calcium carbonate is 20-25μm, the average particle size is 10-12μm, and the maximum particle size of nano silica is 0.4-0.5μm, the average particle size is 0.05-0.1μm.

7. The epoxy composition for bonding camera module brackets according to claim 1, characterized in that, The organic hydrazide is a nitrogen-containing heterocyclic dihydrazide compound.

8. The epoxy composition for bonding camera module brackets according to claim 7, characterized in that, The method for preparing the organic hydrazide is as follows: Under inert gas protection, 5-isopropylhydantoin and methyl acrylate were added to a reactor, along with an alkaline catalyst and a polymerization inhibitor hydroquinone. The reaction was carried out under reflux conditions. After the reaction was completed, excess methyl acrylate was removed to obtain an intermediate, which is the 2:1 molar addition product of 5-isopropylhydantoin and methyl acrylate. Under inert gas protection, the intermediate is dissolved in ethanol, and an ethanol solution of hydrazine hydrate is slowly added. The mixture is refluxed to carry out the reaction. After the reaction is completed, the organic hydrazide is obtained by post-treatment and purification.

9. The epoxy composition for bonding camera module brackets according to claim 7, characterized in that, The organic hydrazide has the following structure: 。 10. A method for preparing an epoxy composition for bonding camera module brackets as described in any one of claims 1-9, characterized in that, The preparation method includes the following steps: Weigh the required weights of epoxy resin, flexible epoxy resin, core-shell epoxy resin toughening agent, compound filler, and organic hydrazide, mix them thoroughly and evenly, add the required weights of modified amine adduct, and mix thoroughly and evenly under vacuum conditions to obtain the epoxy composition that can be used for bonding camera module brackets.

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