Preparation method and application of modified carbon nanotube and preparation method and application of epoxy molding compound

Abstract

The invention relates to the field of epoxy molding compounds, and discloses a preparation method and application of a modified carbon nanotube and a preparation method and application of an epoxy molding compound. The preparation method comprises the following steps: (1) mixing a mixed acid solution with a carbon nanotube for reaction to obtain an acidified carbon nanotube; (2) mixing a mixed solution of thionyl chloride and N, N-dimethylformamide with the acidified carbon nano tube for reaction to obtain an acylating chlorination carbon nano tube; (3) under the protection of an inert gas, mixing the acylating chlorination carbon nano tube with ethanediamine for reaction to obtain an amino modified carbon nano tube; and (4) carrying out ultrasonic treatment on the amino modified carbon nanotube and a modifier containing an epoxy group. The epoxy molding compound prepared from the modified carbon nanotube has excellent strength and toughness, can effectively solve the problems of insufficient strength and toughness and the like of the existing epoxy molding compound, and can be well used in the field of electronic packaging.

Description

Technical Field

[0001] The invention relates to the field of epoxy molding compounds, and in particular to a preparation method and application of modified carbon nanotubes and a preparation method and application of epoxy molding compounds. Background Art

[0002] Epoxy resin is used as the main resin and curing agent and is cured at high temperature under the action of a curing accelerator. The combination of epoxy resin and phenolic resin is the mainstream of today's electronic plastic packaging materials. The above materials are supplemented with inorganic fillers such as silica and calcium carbonate, as well as flame retardants and various additives to prepare plastic packaging materials that meet the needs of electronic packaging.

[0003] However, the strength and toughness of the epoxy molding compounds commonly used today are relatively low. In actual applications, especially after the materials are molded, problems such as product cracking often occur.

[0004] Chinese patent application CN 109627425A discloses a modified bentonite / epoxy resin composite material and a preparation method thereof. The modified bentonite / epoxy resin composite material is only modified E-51 epoxy resin. Due to the low basic performance, although the prepared epoxy resin composite material has greatly improved performance, it still cannot meet the use requirements of electronic plastic packaging materials. At the same time, since the extruded product has been solidified and formed, it cannot be used for electronic material packaging.

[0005] Chinese patent CN111117540B discloses an organic bentonite modified high-strength and high-heat-resistant epoxy molding compound for semiconductor packaging, the bending strength of which can reach 180MPa, but no attention has been paid to the toughness of the material. Therefore, in the field of electronic packaging materials, it is still necessary to find a method that can effectively improve the strength and toughness of epoxy molding compounds at the same time. Summary of the invention

[0006] The purpose of the present invention is to overcome the problems that the strength and toughness of epoxy molding compounds in the prior art need to be further improved, and to provide a preparation method and application of modified carbon nanotubes and a preparation method and application of epoxy molding compounds. The epoxy molding compound prepared by using the modified carbon nanotubes of the present invention has excellent strength and toughness, which can effectively solve the problems of insufficient strength and toughness of the current epoxy molding compounds, and can be well used in the field of electronic packaging.

[0007] In order to achieve the above object, the present invention provides a method for preparing modified carbon nanotubes, which comprises the following steps:

[0008] (1) reacting the mixed acid solution with carbon nanotubes to obtain acidified carbon nanotubes;

[0009] (2) reacting a mixture of thionyl chloride and N,N-dimethylformamide with the acidified carbon nanotubes to obtain acyl chloride carbon nanotubes;

[0010] (3) reacting the acyl chloride carbon nanotubes with ethylenediamine under the protection of an inert gas to obtain amino-modified carbon nanotubes;

[0011] (4) subjecting the amino-modified carbon nanotubes and the modifier containing an epoxy group to ultrasonic treatment;

[0012] The mixed acid solution is a mixed solution of a sulfuric acid solution and a nitric acid solution, the concentration of the sulfuric acid solution is 90-98wt%, and the concentration of the nitric acid solution is 65-70wt%.

[0013] Preferably, in step (1), the reaction conditions include: temperature of 70-90°C, time of 1-4h; and / or

[0014] The mixed acid solution is obtained by mixing the sulfuric acid solution and the nitric acid solution in a volume ratio of 1-4:1.

[0015] Preferably, in step (2), the reaction conditions include: temperature of 60-80°C, time of 20-25h; and / or

[0016] In the mixed solution of thionyl chloride and N,N-dimethylformamide, the volume ratio of thionyl chloride to N,N-dimethylformamide is 18-21:1.

[0017] Preferably, in step (3), the reaction conditions include: temperature of 90-120°C and time of 45-50h;

[0018] Preferably, the epoxy-containing modifier is an epoxy-containing modifier having a C4-C 10 An alkyl glycidyl ether compound, preferably at least one of n-butyl glycidyl ether, octyl glycidyl ether and decyl glycidyl ether; and / or

[0019] The weight ratio of the carbon nanotubes to the epoxy-containing modifier is 1:10-1:5.

[0020] Preferably, in step (4), the conditions of the ultrasonic treatment include: power of 550-650 W and time of 2-8 h.

[0021] The second aspect of the present invention provides a modified carbon nanotube prepared by the above preparation method.

[0022] The third aspect of the present invention provides an epoxy molding compound, which contains epoxy resin, phenolic resin, solid filler, the modified carbon nanotubes, ion capture agent, low stress modifier, coupling agent, accelerator and release agent;

[0023] Preferably, the content of the epoxy resin is 5-12% by weight, the content of the phenolic resin is 2-10% by weight, the content of the solid filler is 75-90% by weight, the content of the modified carbon nanotubes is 0.3-1.0% by weight, the content of the ion capture agent is 0.1-1.0% by weight, the content of the low stress modifier is 0.1-1.0% by weight, the content of the coupling agent is 0.1-1.0% by weight, the content of the accelerator is 0.1-0.5% by weight, and the content of the release agent is 0.1-0.8% by weight.

[0024] The fourth aspect of the present invention provides a method for preparing the epoxy molding compound, which comprises: heating and melting the epoxy resin and the modified carbon nanotubes, then cooling and crushing, then mixing the obtained material with phenolic resin, solid filler, accelerator, low stress modifier, coupling agent, release agent and ion capture agent, and then kneading the obtained mixture.

[0025] A fifth aspect of the present invention provides an application of the epoxy molding compound in an electronic packaging process.

[0026] The method described in the present invention prepares modified carbon nanotubes through a series of reactions of carbon nanotubes. The modified carbon nanotubes have better compatibility with epoxy resin, can effectively solve the dispersion and interface problems of carbon nanotubes in resin, and have better interface strength. The epoxy molding compound prepared by using the modified carbon nanotubes can have excellent strength and toughness at the same time, which can meet the requirements of high-performance packaging and have good reliability and formability. DETAILED DESCRIPTION

[0027] The specific embodiments of the present invention are described in detail below. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0028] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0029] The method for preparing the modified carbon nanotubes of the present invention comprises the following steps:

[0030] (1) reacting the mixed acid solution with carbon nanotubes to obtain acidified carbon nanotubes;

[0031] (2) reacting a mixture of thionyl chloride and N,N-dimethylformamide with the acidified carbon nanotubes to obtain acyl chloride carbon nanotubes;

[0032] (3) reacting the acyl chloride carbon nanotubes with ethylenediamine under the protection of an inert gas to obtain amino-modified carbon nanotubes;

[0033] (4) Ultrasonic treatment is performed on the amino-modified carbon nanotubes and the modifier containing epoxy groups.

[0034] In the method of the present invention, in step (1), the mixed acid solution is a mixed solution of sulfuric acid solution and nitric acid solution, the concentration of the sulfuric acid solution is 90-98wt%, preferably 96-98wt%, and the concentration of the nitric acid solution is 65-70wt%, preferably 67-69wt%. The mixed acid solution reacts with the carbon nanotubes to produce acidified carbon nanotubes.

[0035] In a specific embodiment, step (1) further comprises washing the prepared acidified carbon nanotubes with water until they are neutral, and then drying them.

[0036] In a preferred embodiment, in order to better acidify the carbon nanotubes, the mixed acid solution is obtained by mixing the sulfuric acid solution and the nitric acid solution in a volume ratio of 1-4:1, preferably by mixing the sulfuric acid solution and the nitric acid solution in a volume ratio of 1-3:1, and more preferably by mixing the sulfuric acid solution and the nitric acid solution in a volume ratio of 3:1.

[0037] In a preferred embodiment, the reaction conditions include: a temperature of 70-90°C and a reaction time of 1-4 hours. Specifically, the reaction temperature may be 70°C, 80°C or 90°C; and the reaction time may be 1 hour, 2 hours, 3 hours or 4 hours.

[0038] In a specific embodiment, in step (1), the amount relationship between the mixed acid solution and the carbon nanotubes is not emphasized. During the reaction, it is sufficient to ensure that the mixed acid solution completely submerges the carbon nanotubes.

[0039] In the method of the present invention, in step (2), chlorinated carbon nanotubes are prepared by reacting thionyl chloride and N,N-dimethylformamide with acidified carbon nanotubes. In a preferred embodiment, the reaction conditions include: a temperature of 60-80°C and a reaction time of 20-25 hours. Specifically, the reaction temperature can be 60°C, 70°C or 80°C; the reaction time can be 20 hours, 21 hours, 22 hours, 23 hours, 24 hours or 25 hours.

[0040] In a preferred embodiment, in the mixed solution of thionyl chloride and N,N-dimethylformamide, the volume ratio of thionyl chloride to N,N-dimethylformamide is 18-21: 1. Specifically, the volume ratio of thionyl chloride to N,N-dimethylformamide can be 18: 1, 19: 1, 20: 1 or 21: 1.

[0041] In a specific embodiment, in step (2), the amount relationship between the mixed solution of dichlorothionyl and N,N-dimethylformamide and the acidified carbon nanotubes prepared in step (1) is not limited during the reaction process, and it is only necessary to ensure that the mixed solution completely submerges the acidified nanotubes.

[0042] In the method of the present invention, in step (3), the chlorinated carbon nanotubes are reacted with ethylenediamine to graft amino groups onto the carbon nanotubes to obtain amino-modified carbon nanotubes.

[0043] In a specific embodiment, the amount of the chlorinated carbon nanotubes and the ethylenediamine in step (3) is not limited, and it is only necessary to ensure that the amino-modified carbon nanotubes can be prepared.

[0044] In a preferred embodiment, in step (3), the reaction conditions include: a temperature of 90-120°C and a reaction time of 45-50 hours. Specifically, the reaction temperature may be 90°C, 100°C, 110°C or 120°C; and the reaction time may be 45h, 46h, 47h, 48h, 49h or 50h.

[0045] In a specific embodiment, in step (3), the inactive gas refers to a gas that does not participate in the reaction during the reaction. In a specific embodiment, the inactive gas is selected from at least one of nitrogen and an inert gas (such as argon).

[0046] In the method of the present invention, the amino-modified carbon nanotubes are further reacted with the modifier containing epoxy groups, and the epoxy groups in the modifier containing epoxy groups can be further reacted with the amino groups on the amino-modified carbon nanotubes to obtain the final product modified carbon nanotubes. The carbon nanotubes prepared by the method of the present invention can have better compatibility with epoxy resin, are more tightly combined with the resin matrix, and have higher strength of the bonding interface, so that the prepared epoxy molding compound can have both excellent strength performance and toughness, and can be used very well in electronic packaging.

[0047] In the method of the present invention, the epoxy-containing modifier and the amino-modified carbon nanotubes further react under ultrasonic conditions to prepare modified carbon nanotubes.

[0048] In a preferred embodiment, in order to make the performance of the prepared modified carbon nanotubes more excellent, the epoxy-containing modifier is a C4-C 10 The alkyl glycidyl ether compound is preferably at least one of n-butyl glycidyl ether, octyl glycidyl ether and decyl glycidyl ether, and more preferably n-butyl glycidyl ether.

[0049] In a preferred embodiment, the weight ratio of the carbon nanotubes to the epoxy-containing modifier is 1:10-1:5, preferably 1:8-1:5, and more preferably 1:6. Specifically, the weight ratio of the carbon nanotubes to the epoxy-containing modifier can be 1:5, 1:6, 1:7, 1:8, 1:9 or 1:10.

[0050] In the method of the present invention, the reaction is promoted by ultrasonic wave, which can make the carbon nanotubes more dispersible on the one hand, and can make the carbon nanotubes and the epoxy-containing modifier react mechanically and chemically on the other hand, and promote the reaction more thoroughly, and ensure the structure of the prepared modified carbon nanotubes. In step (4), the power during the ultrasonic treatment is particularly important for the performance of the prepared modified carbon nanotubes, and directly affects the strength and toughness of the epoxy molding compound prepared by the carbon nanotubes. In a preferred embodiment, in step (4), the conditions of the ultrasonic treatment include: the power is 550-650W, more preferably 580-620W, and the time is 2-8h. Specifically, the power of the ultrasonic wave can be 550W, 580W, 600W, 620W or 650W, and the reaction time can be 2h, 3h, 4h, 5h, 6h, 7h or 8h.

[0051] The present invention can also provide a modified carbon nanotube prepared according to the method described in the present invention, wherein the modified carbon nanotube can effectively improve the dispersibility of the carbon nanotube in the resin, and further improve the bonding strength between the carbon nanotube and the resin interface, thereby greatly improving the strength and toughness of the epoxy molding compound prepared by using the modified carbon nanotube, so that the prepared epoxy molding compound can meet the high-performance packaging requirements, and at the same time have good reliability and molding performance.

[0052] The present invention further provides an epoxy molding compound, which contains epoxy resin, phenolic resin, solid filler, the modified carbon nanotube, ion capture agent, low stress modifier, coupling agent, accelerator and release agent.

[0053] In the epoxy molding compound described in the present invention, the modified carbon nanotubes described in the present invention can significantly improve the performance of the epoxy molding compound, and also have the function of a colorant, so there is no need to add additional colorants to the composition described in the present invention.

[0054] In a preferred embodiment, in order to further improve the strength and toughness of the epoxy molding compound, in the epoxy molding compound, the content of the epoxy resin is 5-12% by weight, the content of the phenolic resin is 2-10% by weight, the content of the solid filler is 75-90% by weight, the content of the modified carbon nanotubes is 0.3-1.0% by weight, the content of the ion capture agent is 0.1-1.0% by weight, the content of the low stress modifier is 0.1-1.0% by weight, the content of the coupling agent is 0.1-1.0% by weight, the content of the accelerator is 0.1-0.5% by weight, and the content of the release agent is 0.1-0.8% by weight.

[0055] In a specific embodiment, the specific selection and composition of the epoxy resin in the composition for preparing the epoxy molding compound are not limited. The modified carbon nanotubes described in the present invention can be adapted to a variety of epoxy resins, and can improve their dispersibility and compatibility in the resin to a certain extent. For example, the epoxy resin can be selected from one or more of o-cresol epoxy resin, biphenyl epoxy resin, multifunctional epoxy resin, aralkyl epoxy resin, ester ring epoxy resin, heterocyclic epoxy resin, bisphenol A epoxy resin, bisphenol F epoxy resin, dicyclopentadiene epoxy resin and naphthalene ring epoxy resin.

[0056] In a preferred embodiment, in order to further improve the performance of the prepared epoxy molding compound, the epoxy resin is selected from one or more of o-cresol epoxy resin, biphenyl epoxy resin, multifunctional epoxy resin and dicyclopentadiene epoxy resin.

[0057] In the method of the present invention, the specific composition or type of the phenolic resin is not limited. Specifically, the phenolic resin can be selected from one or more of linear phenolic resin, biphenyl phenolic resin, naphthalene phenolic resin and aralkyl phenolic resin, preferably one or more of linear phenolic resin, biphenyl phenolic resin and aralkyl phenolic resin.

[0058] In a preferred embodiment, the solid filler is selected from crystalline silica powder and / or fused silica powder, preferably fused silica powder.

[0059] In a preferred embodiment, the accelerator is selected from one or more of triphenylphosphine and its derivatives, imidazole, 2-methylimidazole, 2-ethyl-4-methylimidazole, 1,8-diazabicycloundec-7-ene and organic amines, and triphenylphosphine and its derivatives are further preferred.

[0060] In a preferred embodiment, the low stress modifier is selected from one or more of silicone-modified epoxy resin, silicone resin, liquid carboxyl-terminated nitrile rubber and triblock copolymer containing silicone component, and silicone-modified epoxy resin is more preferred.

[0061] In a preferred embodiment, the coupling agent is selected from one or more of γ-glycidyl ether trimethoxy silane, γ-aminopropyl triethoxy silane, γ-mercaptopropyl trimethoxy silane and γ-aminopropyl trimethoxy silane, and more preferably γ-glycidyl ether trimethoxy silane.

[0062] In a preferred embodiment, the release agent is selected from one or more of carnauba wax, polyethylene wax, oxidized polyethylene wax, Fischer-Tropsch wax, polypropylene wax, and fatty acid wax, and is more preferably oxidized polyethylene wax.

[0063] In a preferred embodiment, the ion scavenger is selected from one or more of an anion scavenger, a cation scavenger, an anion-cation composite ion scavenger and a hydrotalcite compound, and is more preferably a hydrotalcite compound.

[0064] The present invention also provides a method for preparing epoxy molding compound, which comprises: mixing epoxy resin and the modified carbon nanotubes, heating and melting them, and then cooling and crushing them; then mixing the obtained material with phenolic resin, solid filler, accelerator, low stress modifier, coupling agent, release agent and ion capture agent, and then kneading the obtained mixture.

[0065] In the method for preparing epoxy molding compound described in the present invention, by first fully mixing the epoxy resin and the modified carbon nanotubes, and then mixing the obtained mixture with the remaining material, the dispersibility of the material can be improved, and the modified carbon nanotubes can be dispersed more evenly in the material, so that the performance of the prepared epoxy molding compound is better.

[0066] In a preferred embodiment, the heating and melting temperature is 100-150°C, more preferably 110-130°C, specifically, the heating and melting temperature may be 100°C, 110°C, 120°C, 130°C, 140°C or 150°C.

[0067] In a preferred embodiment, the epoxy resin and the modified carbon nanotubes are mixed by stirring and then heated to melt. Preferably, the stirring time is 30-90 minutes.

[0068] In a specific implementation, the epoxy resin and the modified carbon nanotubes are mixed and heated to melt, and then cooled to room temperature and crushed and sieved, and the sieved material is taken for later use.

[0069] In a preferred embodiment, the mixing temperature is 80-110° C., preferably 90-100° C. Specifically, the mixing temperature may be 80° C., 90° C., 100° C. or 110° C.

[0070] In a specific embodiment, the mixing time is 6-10 minutes.

[0071] The present invention also provides an application of the epoxy molding compound in an electronic packaging process. The epoxy molding compound of the present invention has extremely high bending strength and impact strength, good formability, high reliability, and can be well applied in electronic packaging.

[0072] The present invention will be described in detail below through examples, but the protection scope of the present invention is not limited thereto.

[0073] The experimental methods in the following examples, unless otherwise specified, are all conventional methods in the art; the experimental raw materials used in the following examples, unless otherwise specified, are all conventional commercially available products in the art.

[0074] The carbon nanotubes used in the following examples and comparative examples were purchased from Jiangsu Tiannai Technology Co., Ltd., with the brand name FT6000;

[0075] The biphenyl epoxy resin used was purchased from Mitsubishi Chemical Corporation with the brand name YX4000.

[0076] The multifunctional epoxy resin used was purchased from DIC Corporation, brand HP 7241;

[0077] The o-cresol epoxy resin used was purchased from Jinan Shengquan Group Co., Ltd. with the brand name SQCN 700-3;

[0078] The dicyclopentadiene epoxy resin used was purchased from DIC Corporation and its brand number is HP 7200.

[0079] The linear phenolic resin used was purchased from Jinan Shengquan Group Co., Ltd., with the brand name PF 8010;

[0080] The aralkylphenol-type phenolic resin used was purchased from Jinan Shengquan Group Co., Ltd. with the brand name SH4064;

[0081] The biphenyl phenolic resin used was purchased from Meiwa Co., Ltd., with the brand name MEH 7851SS;

[0082] The accelerator used was triphenylphosphine, purchased from Nanjing Lanbi'an Biochemical Technology Co., Ltd.;

[0083] The low stress modifier used is silicone modified epoxy resin purchased from Dow Corning Company with the brand name SF-8241EG;

[0084] The coupling agent used was γ-glycidyl ether trimethoxysilane (silane coupling agent KH560), purchased from Jiangsu Chenguang Company;

[0085] The ion capture agent used is hydrotalcite, which is purchased from Kyowa Chemical Industry Co., Ltd. of Japan and has the brand name DHT-4C.

[0086] In the following examples and comparative examples, please see Table 1 for the specific selection of ingredients and specific amounts of each raw material used in the preparation of epoxy molding compound.

[0087] Example 1

[0088] (1) dissolving carbon nanotubes in a mixed acid solution (the volume ratio of sulfuric acid solution to nitric acid solution is 3:1, the concentration of sulfuric acid solution is 98 wt %, and the concentration of nitric acid solution is 68 wt %), reacting at 80° C. for 2 h to obtain acidified carbon nanotubes;

[0089] (2) dissolving the acidified carbon nanotubes in a mixture of thionyl chloride and DMF in a volume ratio of 20:1, raising the temperature to 70° C., stirring and reacting for 24 hours, and then filtering, washing the obtained filter residue with tetrahydrofuran, and then vacuum drying to obtain acyl chloride carbon nanotubes;

[0090] (3) under nitrogen protection, mixing the chlorinated carbon nanotubes with ethylenediamine, reacting at 100° C. for 48 h, filtering the obtained product, washing the obtained filter residue with tetrahydrofuran, and then drying to obtain amino-modified carbon nanotubes;

[0091] (4) in an ultrasonic environment, the amino-modified carbon nanotubes and n-butyl glycidyl ether were mixed and reacted for 4 hours at an ultrasonic power of 550 W. After the reaction, the obtained material was placed in an oven at 80° C. for drying to obtain modified carbon nanotubes, wherein the weight ratio of the carbon nanotubes to n-butyl glycidyl ether was 1:5;

[0092] (5) The epoxy resin and the modified carbon nanotubes are mixed, and then heated to 120° C. to melt, stirred thoroughly for 60 minutes, cooled to 25° C. and then crushed, and the sieved material is sieved; the sieved material, phenolic resin, solid filler, accelerator, low stress modifier, coupling agent, release agent and ion capture agent are then mixed, and the mixture is added to an open mill for mixing at a mixing temperature of 100° C. and mixed for 8 minutes to obtain the epoxy molding compound.

[0093] Example 2

[0094] (1) dissolving carbon nanotubes in a mixed acid solution (the volume ratio of sulfuric acid solution to nitric acid solution is 3:1, the concentration of sulfuric acid solution is 98 wt %, and the concentration of nitric acid solution is 68 wt %), reacting at 80° C. for 2 h to obtain acidified carbon nanotubes;

[0095] (2) dissolving the acidified carbon nanotubes in a mixture of thionyl chloride and DMF in a volume ratio of 20:1, raising the temperature to 70° C., stirring and reacting for 24 hours, and then filtering, washing the obtained filter residue with tetrahydrofuran, and then vacuum drying to obtain acyl chloride carbon nanotubes;

[0096] (3) under nitrogen protection, mixing the chlorinated carbon nanotubes with ethylenediamine, reacting at 100° C. for 48 h, filtering the obtained product, washing the obtained filter residue with tetrahydrofuran, and then drying to obtain amino-modified carbon nanotubes;

[0097] (4) In an ultrasonic environment, the amino-modified carbon nanotubes and n-butyl glycidyl ether were mixed and reacted for 4 hours at an ultrasonic power of 570 W. After the reaction, the obtained material was placed in an oven at 80° C. for drying to obtain modified carbon nanotubes, wherein the weight ratio of the carbon nanotubes to n-butyl glycidyl ether was 1:5;

[0098] (5) The epoxy resin and the modified carbon nanotubes are mixed, and then heated to 110° C. to melt, stirred thoroughly for 80 minutes, cooled to 25° C. and then crushed, and the sieved material is sieved; the sieved material, phenolic resin, solid filler, accelerator, low stress modifier, coupling agent, release agent and ion capture agent are then mixed, and the mixture is added to an open mill for mixing at a mixing temperature of 95° C. After mixing for 7 minutes, the epoxy molding compound is obtained.

[0099] Example 3

[0100] (1) dissolving carbon nanotubes in a mixed acid solution (the volume ratio of sulfuric acid solution to nitric acid solution is 3:1, the concentration of sulfuric acid solution is 98 wt %, and the concentration of nitric acid solution is 68 wt %), reacting at 80° C. for 2 h to obtain acidified carbon nanotubes;

[0101] (2) dissolving the acidified carbon nanotubes in a mixture of thionyl chloride and DMF in a volume ratio of 20:1, raising the temperature to 70° C., stirring and reacting for 24 hours, and then filtering, washing the obtained filter residue with tetrahydrofuran, and then vacuum drying to obtain acyl chloride carbon nanotubes;

[0102] (3) under nitrogen protection, mixing the chlorinated carbon nanotubes with ethylenediamine, reacting at 100° C. for 48 h, filtering the obtained product, washing the obtained filter residue with tetrahydrofuran, and then drying to obtain amino-modified carbon nanotubes;

[0103] (4) in an ultrasonic environment, the amino-modified carbon nanotubes and n-butyl glycidyl ether were mixed and reacted for 4 hours at an ultrasonic power of 600 W. After the reaction, the obtained material was placed in an oven at 80° C. for drying to obtain modified carbon nanotubes, wherein the weight ratio of the carbon nanotubes to n-butyl glycidyl ether was 1:7;

[0104] (5) The epoxy resin and the modified carbon nanotubes are mixed, and then heated to 130° C. to melt, stirred thoroughly for 60 minutes, cooled to 25° C. and crushed, and the sieved material is sieved; the sieved material, phenolic resin, solid filler, accelerator, low stress modifier, coupling agent, release agent and ion capture agent are then mixed, and the mixture is added to an open mill for mixing at a mixing temperature of 100° C. and mixed for 7 minutes to obtain the epoxy molding compound.

[0105] Example 4

[0106] (1) dissolving carbon nanotubes in a mixed acid solution (the volume ratio of sulfuric acid solution to nitric acid solution is 3:1, the concentration of sulfuric acid solution is 98 wt %, and the concentration of nitric acid solution is 68 wt %), reacting at 80° C. for 2 h to obtain acidified carbon nanotubes;

[0107] (2) dissolving the acidified carbon nanotubes in a mixture of thionyl chloride and DMF in a volume ratio of 20:1, raising the temperature to 70° C., stirring and reacting for 24 hours, and then filtering, washing the obtained filter residue with tetrahydrofuran, and then vacuum drying to obtain acyl chloride carbon nanotubes;

[0108] (3) under nitrogen protection, mixing the chlorinated carbon nanotubes with ethylenediamine, reacting at 100° C. for 48 h, filtering the obtained product, washing the obtained filter residue with tetrahydrofuran, and then drying to obtain amino-modified carbon nanotubes;

[0109] (4) in an ultrasonic environment, the amino-modified carbon nanotubes and n-butyl glycidyl ether were mixed and reacted for 4 hours, the ultrasonic power was 650 W, and after the reaction, the obtained material was placed in an oven at 80° C. for drying to obtain modified carbon nanotubes, wherein the weight ratio of the carbon nanotubes to n-butyl glycidyl ether was 1:10;

[0110] (5) The epoxy resin and the modified carbon nanotubes are mixed, and then heated to 120° C. to melt, stirred thoroughly for 60 minutes, cooled to 25° C. and then crushed, and the sieved material is sieved; the sieved material, phenolic resin, solid filler, accelerator, low stress modifier, coupling agent, release agent and ion capture agent are then mixed, and the mixture is added to an open mill for mixing at a mixing temperature of 100° C. and mixed for 7 minutes to obtain the epoxy molding compound.

[0111] Example 5

[0112] (1) dissolving carbon nanotubes in a mixed acid solution (the volume ratio of sulfuric acid solution to nitric acid solution is 3:1, the concentration of sulfuric acid solution is 98 wt %, and the concentration of nitric acid solution is 68 wt %), reacting at 80° C. for 2 h to obtain acidified carbon nanotubes;

[0113] (2) dissolving the acidified carbon nanotubes in a mixture of thionyl chloride and DMF in a volume ratio of 20:1, raising the temperature to 70° C., stirring and reacting for 24 hours, and then filtering, washing the obtained filter residue with tetrahydrofuran, and then vacuum drying to obtain acyl chloride carbon nanotubes;

[0114] (3) under nitrogen protection, mixing the chlorinated carbon nanotubes with ethylenediamine, reacting at 100° C. for 48 h, filtering the obtained product, washing the obtained filter residue with tetrahydrofuran, and then drying to obtain amino-modified carbon nanotubes;

[0115] (4) In an ultrasonic environment, the amino-modified carbon nanotubes and n-butyl glycidyl ether were mixed and reacted for 4 hours at an ultrasonic power of 630 W. After the reaction, the obtained material was placed in an oven at 80° C. for drying to obtain modified carbon nanotubes, wherein the weight ratio of the carbon nanotubes to n-butyl glycidyl ether was 1:7;

[0116] (5) The epoxy resin and the modified carbon nanotubes are mixed, and then heated to 130° C. to melt, stirred thoroughly for 60 minutes, cooled to 25° C. and then crushed, and the sieved material is sieved; the sieved material, phenolic resin, solid filler, accelerator, low stress modifier, coupling agent, release agent and ion capture agent are then mixed, and the mixture is added to an open mill for mixing at a mixing temperature of 95° C. After mixing for 9 minutes, the epoxy molding compound is obtained.

[0117] Example 6

[0118] (1) dissolving carbon nanotubes in a mixed acid solution (the volume ratio of sulfuric acid solution to nitric acid solution is 3:1, the concentration of sulfuric acid solution is 98 wt %, and the concentration of nitric acid solution is 68 wt %), reacting at 80° C. for 2 h to obtain acidified carbon nanotubes;

[0119] (2) dissolving the acidified carbon nanotubes in a mixture of thionyl chloride and DMF in a volume ratio of 20:1, raising the temperature to 70° C., stirring and reacting for 24 hours, and then filtering, washing the obtained filter residue with tetrahydrofuran, and then vacuum drying to obtain acyl chloride carbon nanotubes;

[0120] (3) under nitrogen protection, mixing the chlorinated carbon nanotubes with ethylenediamine, reacting at 100° C. for 48 h, filtering the obtained product, washing the obtained filter residue with tetrahydrofuran, and then drying to obtain amino-modified carbon nanotubes;

[0121] (4) in an ultrasonic environment, the amino-modified carbon nanotubes and n-butyl glycidyl ether were mixed and reacted for 4 hours, the ultrasonic power was 600 W, and after the reaction, the obtained material was placed in an oven at 80° C. for drying to obtain modified carbon nanotubes, wherein the weight ratio of the carbon nanotubes to n-butyl glycidyl ether was 1:6;

[0122] (5) The epoxy resin and the modified carbon nanotubes are mixed, and then heated to 125° C. to melt, stirred thoroughly for 60 minutes, cooled to 25° C. and then crushed, and the sieved material is sieved; the sieved material, phenolic resin, solid filler, accelerator, low stress modifier, coupling agent, release agent and ion capture agent are then mixed, and the mixture is added to an open mill for mixing at a mixing temperature of 100° C. and mixed for 7 minutes to obtain the epoxy molding compound.

[0123] Comparative Example 1

[0124] The method of Example 1 is followed, except that in the process of preparing the epoxy molding compound (i.e., step (5)), the modified carbon nanotubes are replaced with an equal weight of carbon black for preparation.

[0125] Comparative Example 2

[0126] The method of Example 2 is followed, except that in the process of preparing the epoxy molding compound (i.e., step (5)), the weight of the modified carbon nanotubes is changed to 0.2 weight parts, and the weight of the solid filler is changed to 83.2 weight parts.

[0127] Comparative Example 3

[0128] The method of Example 4 is followed, except that in the process of preparing the epoxy molding compound (i.e., step (5)), the weight of the modified carbon nanotubes is changed to 1.2 parts by weight and the weight of the solid filler is changed to 79.8 parts by weight.

[0129] Comparative Example 4

[0130] The method of Example 6 is followed, except that in step (5), the modified carbon nanotubes are replaced with carbon nanotubes of equal weight for preparation.

[0131] Comparative Example 5

[0132] The method of Example 6 is followed, except that in step (5), the modified carbon nanotubes are replaced with an equal weight portion of amino-modified carbon nanotubes (i.e., the product prepared in step (3)).

[0133] Table 1 Specific ingredients and specific amounts of each raw material used in the preparation process of epoxy molding compound in Examples 1-6 (by weight, unit: g)

[0134]

[0135]

[0136] Note: / indicates that this component is not contained.

[0137] Test Case

[0138] The properties of the epoxy molding materials prepared in Examples 1-6 and the materials prepared in Comparative Examples 1-5 were tested. The specific test results are shown in Table 2. The specific test method is as follows:

[0139] Gelation time: Heat the electric heating plate to 175±1℃, take 2-3g of sample and place it on the iron plate, stir it continuously with a small needle, and test the time it takes for the sample to change from fluid to gel;

[0140] Fluidity: Take 30 grams of the sample to be tested and use a resin transfer injection molding machine with a spiral flow metal mold to measure the fluidity. The injection pressure is 70kgf / cm 2 , mold temperature is 175±1℃;

[0141] Bending strength: The sample to be tested is made into a 15mm×10mm×125mm bending specimen and tested using a universal material testing machine;

[0142] Impact strength: A 15 mm × 10 mm × 100 mm specimen made of the sample to be tested is tested using a simply supported beam impact testing machine.

[0143] Formability: Use the sample to be tested to package the product and check whether the product appearance is good after electroplating.

[0144] Table 2

[0145]

[0146]

[0147] It can be seen from the above embodiments and comparative examples that by modifying carbon nanotubes, the modified carbon nanotubes prepared can effectively solve the dispersion and interface problems of carbon nanotubes in resin, thereby greatly improving the strength and toughness of epoxy molding compounds, which can not only meet high-performance packaging requirements, but also have good reliability and formability.

[0148] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A method for preparing modified carbon nanotubes, characterized in that: The preparation method comprises the following steps: (1) reacting the mixed acid solution with carbon nanotubes to obtain acidified carbon nanotubes; (2) reacting a mixture of thionyl chloride and N,N-dimethylformamide with the acidified carbon nanotubes to obtain acyl chloride carbon nanotubes; (3) reacting the acyl chloride carbon nanotubes with ethylenediamine under the protection of an inert gas to obtain amino-modified carbon nanotubes; (4) subjecting the amino-modified carbon nanotubes and the modifier containing an epoxy group to ultrasonic treatment; Wherein, the mixed acid solution is a mixed solution of sulfuric acid solution and nitric acid solution, the concentration of the sulfuric acid solution is 90-98wt%, and the concentration of the nitric acid solution is 65-70wt%.

2. The preparation method according to claim 1, characterized in that: In step (1), the reaction conditions include: temperature of 70-90°C, time of 1-4h; and / or The mixed acid solution is obtained by mixing the sulfuric acid solution and the nitric acid solution in a volume ratio of 1-4:

1.

3. The preparation method according to claim 1, characterized in that: In step (2), the reaction conditions include: temperature of 60-80°C, time of 20-25h; and / or In the mixed solution of thionyl chloride and N,N-dimethylformamide, the volume ratio of thionyl chloride to N,N-dimethylformamide is 18-21:

1.

4. The preparation method according to claim 1, characterized in that: In step (3), the reaction conditions include: temperature of 90-120° C. and time of 45-50 h.

5. The preparation method according to claim 1, characterized in that: The epoxy-containing modifier is an epoxy-containing modifier having a C4-C 10 An alkyl glycidyl ether compound, preferably at least one of n-butyl glycidyl ether, octyl glycidyl ether and decyl glycidyl ether; and / or The weight ratio of the carbon nanotubes to the epoxy-containing modifier is 1:10-1:

5.

6. The preparation method according to claim 1, characterized in that: In step (4), the conditions of the ultrasonic treatment include: power of 550-650W and time of 2-8h.

7. Modified carbon nanotubes prepared by the method according to any one of claims 1 to 6.

8. An epoxy molding compound, characterized in that: The epoxy molding compound contains epoxy resin, phenolic resin, solid filler, modified carbon nanotubes, ion capture agent, low stress modifier, coupling agent, accelerator and release agent, wherein the modified carbon nanotubes are the modified carbon nanotubes according to claim 7; Preferably, based on the total weight of the epoxy molding compound, the content of the epoxy resin is 5-12% by weight, the content of the phenolic resin is 2-10% by weight, the content of the solid filler is 75-90% by weight, the content of the modified carbon nanotubes is 0.3-1.0% by weight, the content of the ion capture agent is 0.1-1.0% by weight, the content of the low stress modifier is 0.1-1.0% by weight, the content of the coupling agent is 0.1-1.0% by weight, the content of the accelerator is 0.1-0.5% by weight, and the content of the release agent is 0.1-0.8% by weight.

9. A method for preparing the epoxy molding compound according to claim 8, characterized in that: The method comprises: heating and melting epoxy resin and modified carbon nanotubes, cooling and crushing, then mixing the obtained material with phenolic resin, solid filler, accelerator, low stress modifier, coupling agent, release agent and ion capture agent, and then kneading the obtained mixture.

10. Use of the epoxy molding compound according to claim 8 in an electronic packaging process.

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