Phosphorus-containing latent accelerator, epoxy composition and preparation method and application thereof

Abstract

The invention discloses a phosphorus-containing latent accelerator, an epoxy composition and a preparation method and application of the phosphorus-containing latent accelerator and the epoxy composition, and belongs to the technical field of electronic packaging materials. When the phosphorus-containing latent accelerator provided by the invention is applied to a subsequent epoxy composition, the phosphorus-containing latent accelerator can cooperate with components in the epoxy composition, so that the gelation time of the epoxy composition is effectively prolonged, the spiral flow length is increased, the fluidity in a molten state is improved, and the bending strength and modulus of the obtained epoxy composition are also improved; the phosphorus-containing latent accelerator and the epoxy composition prepared by the preparation method provided by the invention have excellent effects. As the epoxy composition provided by the invention has the excellent effects, the epoxy composition can be widely applied to preparation of the electronic packaging material, the comprehensive performance of the electronic packaging material is improved, and the processing difficulty is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of electronic packaging materials, and in particular relates to a phosphorus-containing latent accelerator, an epoxy composition, and a preparation method and application thereof. Background Art

[0002] Epoxy molding compound is a commonly used plastic encapsulation material in the semiconductor industry. It is composed of epoxy resin, curing agent, accelerator, filler, coupling agent, modifier, flame retardant, release agent, colorant, etc. It is mainly used for the encapsulation and protection of electronic components, such as integrated circuits, semiconductor devices, LED chips, power modules, electronic transformers, sensors, etc. Its excellent electrical properties, mechanical properties and chemical resistance can make electronic components have good insulation, heat resistance, corrosion resistance and mechanical strength, effectively protect electronic components from moisture, corrosion and mechanical damage, thereby improving the reliability and service life of electronic components. At present, more than 95% of electronic components are encapsulated with epoxy molding compound.

[0003] As the requirements for electronic devices increase day by day, better performance, better portability, etc., the performance requirements for packaging materials are also correspondingly improved. In order to meet the special functions and application scenarios of electronic devices, such as thermal conductivity, electromagnetic shielding, etc., functional fillers need to be added. Compared with traditional fillers, these powders have poor surface properties and poor compatibility with epoxy. As a result, functional epoxy molding compound products often have defects such as poor temperature resistance, poor density, low mechanical strength, poor fluidity, and low addition amount. Poor mechanical properties can easily lead to stress cracking, warping, and reduce reliability. Poor fluidity will make it difficult to implement the process, and defects such as flash and voids will appear. This is one of the difficulties faced by functional epoxy molding compounds at this stage. Summary of the invention

[0004] The object of the present invention is to solve the above problems and provide a phosphorus-containing latent accelerator, an epoxy composition, a preparation method and an application thereof, wherein the product obtained after being applied to the epoxy composition has good fluidity, stability and excellent mechanical properties.

[0005] To achieve the above object, in a first aspect of the present invention, the present invention provides a method for preparing a phosphorus-containing latent accelerator, the preparation method comprising the following steps:

[0006] Tetraphenylphosphine bromide and a diphenol compound are added to an alcohol solution, and then a metal hydroxide is added to carry out a complex reaction. After the reaction is completed, the solution is filtered and washed, and the filter residue is collected to obtain a phosphorus-containing latent accelerator.

[0007] The diphenol compound includes at least one of 4,4-dihydroxybiphenyl and hydroquinone.

[0008] The present invention has been found through research that the phosphorus-containing latent accelerator prepared by the preparation method provided by the present invention can be well applied to epoxy compositions as an accelerator, can effectively prolong the gel time of the epoxy composition, increase the spiral flow length, and improve the fluidity of the molten state, and the bending strength and modulus of the obtained epoxy composition are also improved; that is, the phosphorus-containing latent accelerator prepared by the preparation method provided by the present invention has excellent effects.

[0009] Preferably, the reaction process of the phosphorus-containing latent accelerator is as shown in Formula I and Formula II respectively;

[0010]

[0011] As a preferred embodiment of the preparation method of the present invention, the temperature of the complex reaction is 20-30° C. and the time is 3-6 hours.

[0012] As a preferred embodiment of the preparation method of the present invention, the molar ratio of tetraphenylphosphonium bromide, diphenol compound and metal hydroxide is 1:(2.5-5):(1-4).

[0013] Exemplarily, the molar ratio of tetraphenylphosphine bromide, diphenol compound and metal hydroxide can be any point value or any two point range values ​​between 1:(2.5-5):(1-4), for example, it can be 1:2.5:1, 1:2.5:2, 1:2.5:3, 1:2.5:4, 1:3.5:1, 1:3.5:2, 1:3.5:3, 1:3.5:4, 1:5:1, 1:5:2, 1:5:3, 1:5:4, etc.

[0014] As a preferred embodiment of the preparation method of the present invention, the mass volume ratio of tetraphenylphosphonium bromide and alcohol is 1g:(10-30)mL.

[0015] The present invention has found that when the parameters in the preparation process are further selected to be within the above range, the yield of the obtained phosphorus-containing latent promoter is higher.

[0016] As a preferred embodiment of the preparation method of the present invention, the washing is performed until the pH value of the washing liquid is 7.0-8.0.

[0017] As a preferred embodiment of the preparation method of the present invention, the alcohol includes methanol.

[0018] As a preferred embodiment of the preparation method of the present invention, the metal hydroxide includes sodium hydroxide and potassium hydroxide.

[0019] In a second aspect of the present invention, the present invention provides a phosphorus-containing latent accelerator, and the phosphorus-containing latent accelerator is prepared by the preparation method of the present invention.

[0020] In the third aspect of the present invention, the present invention provides the use of the phosphorus-containing latent accelerator in the preparation of an epoxy composition.

[0021] In a fourth aspect of the present invention, the present invention provides an epoxy composition, wherein the epoxy composition comprises the phosphorus-containing latent accelerator of the present invention.

[0022] As a preferred embodiment of the epoxy composition of the present invention, the epoxy composition comprises the following components in parts by weight: 5-10 parts of epoxy resin, 2-10 parts of curing agent, 75-110 parts of inorganic filler, and 0.05-1 part of phosphorus-containing latent accelerator.

[0023] The present invention has been found that by using the phosphorus-containing latent accelerator provided by the present invention as a component of the epoxy composition, it can cooperate well with other components to effectively prolong the gel time of the epoxy composition, increase the spiral flow length, and improve the fluidity of the molten state, and the bending strength and modulus of the obtained epoxy composition are also improved.

[0024] As a preferred embodiment of the epoxy composition of the present invention, the epoxy composition further comprises the following components in parts by weight: 0.1-1 parts of coupling agent, 0.5-2 parts of stress modifier, 0.05-0.2 parts of release agent, 0.1-0.6 parts of defoaming agent, 0.01-0.5 parts of colorant, and 0.1-2 parts of flame retardant.

[0025] The present invention has found that further adding the above-mentioned components to the epoxy composition can better improve the comprehensive performance of the epoxy composition.

[0026] As a preferred embodiment of the epoxy composition of the present invention, the epoxy resin includes at least one of solid bisphenol A epoxy resin, o-cresol epoxy resin, biphenyl epoxy resin, dicyclopentadiene epoxy resin, naphthalene epoxy resin, and polyaromatic ring epoxy resin.

[0027] Preferably, the epoxy resin includes at least one of o-cresol-formaldehyde epoxy resin and biphenyl epoxy resin.

[0028] The present invention has found that when the epoxy resin further includes at least one of o-cresol-formaldehyde epoxy resin and biphenyl epoxy resin, the epoxy resin interacts with the phosphorus-containing latent accelerator to achieve better fluidity in the molten state.

[0029] As a preferred embodiment of the epoxy composition of the present invention, the curing agent includes at least one of linear phenolic resin, aralkyl phenolic resin, biphenyl aralkyl phenolic resin and linear bisphenol A phenolic resin.

[0030] Preferably, the curing agent includes at least one of linear phenol formaldehyde resin, aralkylphenol resin, and biphenyl aralkylphenol resin.

[0031] As a preferred embodiment of the epoxy composition of the present invention, the inorganic filler includes at least one of spherical silica, crystalline silica and alumina.

[0032] Preferably, the Dv50 particle size of the spherical silica is 1.5-80 μm, the Dv50 particle size of the crystalline silica is 5-40 μm, and the Dv50 particle size of the alumina is 1-50 μm.

[0033] As a preferred embodiment of the epoxy composition of the present invention, the coupling agent includes at least one of γ-aminopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane and γ-mercaptopropyltrimethoxysilane.

[0034] As a preferred embodiment of the epoxy composition of the present invention, the stress modifier includes at least one of carboxyl-terminated nitrile rubber, amine-terminated nitrile rubber, silicone rubber, epoxy-modified silicone resin, methacrylic-containing silane, amino-containing silane, and mercapto-containing silane.

[0035] As a preferred embodiment of the epoxy composition of the present invention, the release agent includes at least one of calcium stearate, carnauba wax, polyethylene wax, oxidized polyethylene wax, Fischer-Tropsch wax, polypropylene wax, and fatty acid wax.

[0036] As a preferred embodiment of the epoxy composition of the present invention, the defoaming agent includes at least one of BYK-535 and BYK-530.

[0037] As a preferred embodiment of the epoxy composition of the present invention, the colorant includes insulating carbon black.

[0038] As a preferred embodiment of the epoxy composition of the present invention, the flame retardant includes at least one of a halogen flame retardant, a phosphorus flame retardant, a nitrogen flame retardant, a phosphorus-halogen flame retardant, a phosphorus-nitrogen flame retardant, and a hydroxide flame retardant.

[0039] In a fifth aspect of the present invention, the present invention provides a method for preparing the epoxy composition, which comprises the following steps: crushing the raw materials and then mixing them, followed by banburying, and further crushing them after the banburying to obtain the epoxy composition.

[0040] As a preferred embodiment of the preparation method of the present invention, the mixing is performed at a rotation speed of 1500-2500 rpm for 25-35 min.

[0041] As a preferred embodiment of the preparation method of the present invention, the banburying is performed by extrusion at 80-100°C.

[0042] In a sixth aspect of the present invention, the present invention provides use of the epoxy composition in preparing electronic packaging materials.

[0043] Compared with the prior art, the present invention has the following beneficial effects:

[0044] The present invention provides a method for preparing a phosphorus-containing latent accelerator. When the phosphorus-containing latent accelerator prepared by the preparation method is applied to a subsequent epoxy composition, it can cooperate with the components in the epoxy composition to effectively extend the gel time of the epoxy composition, increase the spiral flow length, and improve the fluidity of the molten state, and the bending strength and modulus of the epoxy composition obtained are also improved; that is, the phosphorus-containing latent accelerator and the epoxy composition prepared by the preparation method provided by the present invention have excellent effects. Since the epoxy composition provided by the present invention has the above-mentioned excellent effects, it can be widely used in the preparation of electronic packaging materials, improve the comprehensive performance of electronic packaging materials and reduce the difficulty of processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 is the NMR spectrum of phosphorus-containing latent promoter 1;

[0046] Figure 2 is the NMR spectrum of phosphorus-containing latent promoter 2;

[0047] Figure 3 is the infrared spectrum of phosphorus-containing latent accelerator 1;

[0048] Figure 4 is the infrared spectrum of phosphorus-containing latent accelerator 2;

[0049] Figure 5 This is the curing curve diagram in Effect Example 2. DETAILED DESCRIPTION

[0050] In order to better illustrate the purpose, technical solutions and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments.

[0051] Unless otherwise specified, the reagents, methods and equipment used in the present invention are all conventional reagents, methods and equipment in the art; and unless otherwise specified, the raw materials used in parallel experiments are from the same batch of raw materials.

[0052] The names, structures, and manufacturer information of the raw materials used in the present invention are shown in Table 1;

[0053] Table 1

[0054]

[0055]

[0056]

[0057] Example 1

[0058] The embodiment of the present invention provides a phosphorus-containing latent accelerator (self-made accelerator 1, TPPB-HQ), and the preparation method of the phosphorus-containing latent accelerator comprises the following steps:

[0059] 10.48 g of tetraphenylphosphonium bromide (0.025 mol) and 11 g of hydroquinone (0.100 mol) were added to 150 mL of methanol solution, stirred and dissolved at 25 °C, and then 1 g of sodium hydroxide (0.025 mol) was added. After reacting for 3 h, the residue was collected and washed with deionized water until the pH value of the washing liquid was 8. After washing, it was dried in an oven at 85 °C to obtain the homemade accelerator 1.

[0060] Example 2

[0061] The embodiment of the present invention provides a phosphorus-containing latent accelerator (self-made accelerator 2, TBBP-DHDP), and the preparation method of the phosphorus-containing latent accelerator comprises the following steps:

[0062] 10.48 g of tetraphenylphosphonium bromide (0.025 mol) and 18.62 g of 4,4-dihydroxybiphenyl (0.100 mol) were added to 250 mL of methanol solution, stirred and dissolved at 25 °C, and then 4 g of sodium hydroxide (0.100 mol) was added. After reacting for 3 h, the residue was collected and washed with deionized water until the pH value of the washing liquid was 7. After washing, it was dried in an oven at 85 °C to obtain the homemade promoter 2.

[0063] Example 3

[0064] The embodiment of the present invention provides a phosphorus-containing latent accelerator (self-made accelerator 1), and the only difference between the phosphorus-containing latent accelerator and Example 1 is that 5 g of sodium hydroxide (0.125 mol) is added.

[0065] Example 4

[0066] The embodiment of the present invention provides a phosphorus-containing latent accelerator (self-made accelerator 1), and the only difference between the phosphorus-containing latent accelerator and Example 1 is that the amount of hydroquinone is 5.5 g (0.050 mol).

[0067] Example 5

[0068] The embodiment of the present invention provides a phosphorus-containing latent accelerator (self-made accelerator 1). The only difference between the phosphorus-containing latent accelerator and Example 1 is that the reaction is filtered after 1 hour.

[0069] Example 6

[0070] The embodiment of the present invention provides a phosphorus-containing latent accelerator (self-made accelerator 1). The only difference between the phosphorus-containing latent accelerator and Example 1 is that 1 g of sodium hydroxide (0.025 mol) is added after stirring and dissolving at 60° C., and the mixture is reacted for 3 hours and then filtered.

[0071] Example 7

[0072] The embodiment of the present invention provides a phosphorus-containing latent accelerator (self-made accelerator 2), the only difference between the phosphorus-containing latent accelerator and Example 2 is that the amount of 4,4-dihydroxybiphenyl is 9.31 g (0.050 mol).

[0073] Effect Example 1

[0074] Effect Example of the Invention The yield of the phosphorus-containing latent accelerator prepared in Example 1-7 was calculated, yield = target product generation amount / target product theoretical generation amount * 100%; the results obtained are shown in Table 2;

[0075] Table 2

[0076] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Yield 84.3％ 82.8％ 55.2％ 34.1％ 70.1％ 75.9％ 66.8％

[0077] It can be seen from Table 2 that when the parameters in the preparation process are further selected within the preferred range of the present invention, the yield of the obtained phosphorus-containing latent promoter is higher, at more than 82.8%.

[0078] The phosphorus-containing latent accelerators prepared in Example 1 and Example 2 were characterized by using a JNM-ECZ400S nuclear magnetic resonance spectrometer from JEOL and a VERTEX70v infrared spectrometer from Bruker. Figure 1 As shown, the infrared spectrum is Figure 3 As shown, the NMR spectrum of the homemade promoter 2 is as follows Figure 2 As shown, the infrared spectrum is Figure 4 shown; from Figure 1-2 It can be seen that the characteristic hydrogen absorption peak of the synthesized homemade promoter is consistent with the expected product; Figure 3-4 It can be seen that the -1 and 3057cm -1 The characteristic peak of the CH bond of the benzene ring is located at 1587cm -1 and 1588cm -1The characteristic peak of C=C bond is located at 1108cm -1 and 1110cm -1 The characteristic peak of P-Ar bond and the peak at 722cm -1 and 723cm -1 The characteristic absorption peak of PC bond further indicates that the compound with the expected structure was successfully prepared.

[0079] Application Examples 1-10 and Comparative Application Examples 1-3

[0080] The application examples of the present invention and the comparative application examples provide an epoxy composition, the components (parts by mass) of the epoxy composition are shown in Table 3-4;

[0081] Table 3

[0082]

[0083]

[0084] Table 4

[0085]

[0086] The preparation method of the epoxy composition provided in Application Example 1 comprises the following steps: adding the solid components in Table 3 to a high-speed mixer for powdering, mixing at a speed of 2000 rpm for 30 minutes to obtain a premix; adding the premix to the main feeding system of a twin-screw extruder, adding the liquid components to the side feeding system of the twin-screw extruder, mixing and extruding at 90°C, and crushing to obtain an epoxy composition.

[0087] The preparation methods of the epoxy compositions provided in Application Examples 2-10 and Comparative Application Examples 1-3 are consistent with that in Application Example 1.

[0088] Effect Example 2

[0089] The curing performance of the epoxy composition prepared in application examples 1-2 and comparative application examples 1-3 was investigated, mainly by using a TA DSC250 differential scanning calorimeter for testing, with a heating rate of 3°C / min, from 25°C to 250°C, and analyzing the data of the starting, peak, end temperature and curing enthalpy, and the results are shown in Table 5;

[0090] Table 5

[0091] Comparative application example 1 Comparative Application Example 2 Comparative Application Example 3 Application Example 1 Application Example 2 Starting temperature / ℃ 105.90 115.10 117.09 140.07 132.77 Peak temperature / ℃ 124.71 132.42 136.01 160.48 153.09 End temperature / ℃ 140.99 151.82 162.41 178.08 169.69 Curing enthalpy / J / g 251.86 249.22 250.92 262.88 270.17

[0092] It can be seen from Table 5 that when the phosphorus-containing latent accelerator of the present invention is used, the epoxy composition obtained has a high starting temperature, peak temperature, end temperature and curing enthalpy in the curing performance test, that is, it has a good curing effect; wherein the corresponding curing curve is as follows Figure 5 As shown, TPP, TPP-BQ, TPPB, TPPB-HQ, and TPPB-DHDP correspond to comparative application example 1, comparative application example 2, comparative application example 3, application example 1, and application example 2, respectively.

[0093] Effect Example 3

[0094] The effects of the present invention are as follows: The performance of the epoxy compositions prepared by application examples 1-10 and comparative application examples 1-3 is investigated, including the following aspects:

[0095] 1. Gel time: Take 1.0g of epoxy composition and place it on a heating plate at 175±1℃. Start timing when the sample melts and keep pressing with a flat spatula. Stop timing when it turns into a gel state and record the corresponding time.

[0096] 2. Spiral flow length: ASTM D-3123 test is adopted. At 175°C, the transfer pressure is set to 6.9 MPa. The epoxy composition is injected into the spiral flow length test mold preheated to the same temperature through a transfer molding press. The length of the longest continuous point is read and recorded;

[0097] 3. Bending strength: Test according to GB / T9341, with a load application speed of 2 mm / min until the cured epoxy composition product breaks, read the load value and record it;

[0098] 4. Flexural modulus: The epoxy composite parts (size 3*15*50mm) were tested using a TA DMA850 dynamic thermal mechanical analyzer. The test mode was a three-point bending mode, with a fixed amplitude oscillation, a preload force of 0.5N, a heating rate of 3°C / min, and the temperature was increased from 25°C to 280°C. The modulus data at 25°C and 260°C were read and recorded respectively.

[0099] The preparation method of the epoxy composition parts in the bending strength and bending modulus tests is as follows: according to the sample size requirements of each test, the epoxy composition is injected into a mold of a corresponding shape by an injection molding machine at 80-100°C, and cured at 175°C for 6 hours, and then demolded and taken out to obtain the corresponding epoxy composition parts;

[0100] The results obtained are shown in Table 6;

[0101] Table 6

[0102]

[0103] It can be seen from Table 6 that when the preparation method provided by the present invention is adopted, the prepared epoxy composition has a longer gelation time, a longer spiral flow length, and a higher flexural modulus and flexural strength after being prepared into a product; specifically, the obtained epoxy composition has a gelation time of more than 70 s, a spiral flow length of more than 94 cm, a flexural modulus of more than 21.5 GPa at 25° C., a flexural modulus of more than 1.40 GPa at 260° C., and a flexural strength of more than 145.6 MPa;

[0104] It can be seen from Application Example 1 and Comparative Application Examples 1-3 that when a phosphorus-containing latent accelerator other than that provided by the present invention is used, the comprehensive performance of the epoxy composition obtained is significantly reduced; specifically, for example, the gelation time of the epoxy composition obtained in Comparative Application Example 1 is significantly shortened, the spiral flow length is significantly reduced, and the bending modulus and bending strength also show a certain downward trend; the bending modulus of the epoxy composition obtained in Comparative Application Example 2 shows a significant downward trend, and the bending strength, gelation time and spiral flow length also show a certain downward trend; the comprehensive performance of the epoxy composition obtained in Comparative Application Example 3 also shows a significant downward trend.

[0105] Finally, it should be noted that the above embodiments are intended to illustrate the technical solution of the present invention rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention may be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A method for preparing a phosphorus-containing latent accelerator, characterized in that: The preparation method comprises the following steps: Tetraphenylphosphine bromide and a diphenol compound are added to an alcohol solution, and then a metal hydroxide is added to carry out a complex reaction. After the reaction is completed, the mixture is filtered and washed, and the filter residue is collected to obtain a phosphorus-containing latent accelerator. The diphenol compound includes at least one of 4,4-dihydroxybiphenyl and hydroquinone.

2. The preparation method according to claim 1, characterized in that: The temperature of the complexation reaction is 20-30°C and the time is 3-6h; and / or, the molar ratio of tetraphenylphosphine bromide, diphenol compound and metal hydroxide is 1:(2.5-5):(1-4); And / or, the mass volume ratio of tetraphenylphosphonium bromide and alcohol is 1g:(10-30)mL.

3. A phosphorus-containing latent accelerator, characterized in that: The phosphorus-containing latent accelerator is prepared by the preparation method according to any one of claims 1 to 2.

4. Use of the phosphorus-containing latent accelerator as claimed in claim 3 in the preparation of an epoxy composition.

5. An epoxy composition, characterized in that The epoxy composition comprises the phosphorus-containing latent accelerator as claimed in claim 3.

6. The epoxy composition according to claim 5, characterized in that The epoxy composition comprises the following components in parts by weight: 5-10 parts of epoxy resin, 2-10 parts of curing agent, 75-110 parts of inorganic filler, and 0.05-1 part of phosphorus-containing latent accelerator.

7. The epoxy composition according to claim 6, characterized in that The epoxy composition further comprises the following components in parts by weight: 0.1-1 parts of a coupling agent, 0.5-2 parts of a stress modifier, 0.05-0.2 parts of a release agent, 0.1-0.6 parts of a defoaming agent, 0.01-0.5 parts of a colorant, and 0.1-2 parts of a flame retardant.

8. The epoxy composition according to claim 7, characterized in that Satisfy at least one of the following: 1) The epoxy resin includes at least one of solid bisphenol A epoxy resin, o-cresol epoxy resin, biphenyl epoxy resin, dicyclopentadiene epoxy resin, naphthalene epoxy resin, and polyaromatic ring epoxy resin; 2) the curing agent comprises at least one of linear phenolic resin, aralkyl phenolic resin, biphenyl aralkyl phenolic resin and linear bisphenol A phenolic resin; 3) The inorganic filler includes at least one of spherical silica, crystalline silica and alumina; 4) the coupling agent comprises at least one of γ-aminopropyltriethoxysilane, γ-glycidyloxypropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane and γ-mercaptopropyltrimethoxysilane; 5) The stress modifier includes at least one of carboxyl-terminated nitrile rubber, amine-terminated nitrile rubber, silicone rubber, epoxy-modified silicone resin, methacrylic silane, amino-containing silane, and mercapto-containing silane; 6) The release agent includes at least one of calcium stearate, carnauba wax, polyethylene wax, oxidized polyethylene wax, Fischer-Tropsch wax, polypropylene wax, and fatty acid wax; 7) The defoaming agent includes at least one of BYK-535, BYK-530, and AGITAN 260; 8) The colorant includes insulating carbon black; 9) The flame retardant includes at least one of a halogen flame retardant, a phosphorus flame retardant, a nitrogen flame retardant, a phosphorus-halogen flame retardant, a phosphorus-nitrogen flame retardant, and a hydroxide flame retardant.

9. The method for preparing the epoxy composition according to any one of claims 5 to 8, characterized in that: The preparation method comprises the following steps: crushing the raw materials and then mixing them, followed by banburying, and further crushing them after the banburying to obtain the epoxy composition.

10. Use of the epoxy composition according to any one of claims 5 to 8 in preparing electronic packaging materials.

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