Electric epoxy resin curing agent and preparation method thereof

Abstract

The invention relates to the technical field of resin curing agents, in particular to an electric epoxy resin curing agent and a preparation method thereof, and the electric epoxy resin curing agent comprises the following components: an amine compound A: 30-60 parts by weight of aliphatic polyamine or aromatic polyamine; 10 to 30 parts by weight of fluorine-containing monomer B selected from trifluoromethyl-containing acrylate or fluorinated epoxy resin; the modifier C is prepared by weighing 5 to 20 parts by weight of siloxane oligomer or polyhedral oligomeric silsesquioxane; the dielectric constant of a cured product at the frequency of 1MHz is as low as 2.5-3.5, and is reduced by about 30%-40% compared with that of a traditional curing agent (the dielectric constant is 4.0-5.0); meanwhile, the dielectric loss tangent value is less than or equal to 0.005 and is far lower than that of a traditional product (gt; 0.02) of the material (1); by means of the characteristic, energy loss and signal delay in the high-frequency signal transmission process can be effectively reduced, and the requirements of core materials in the high-frequency electronic fields such as 5G / 6G communication base stations, millimeter wave radars and high-speed printed circuit boards are perfectly met.

Description

Technical Field

[0001] This invention relates to the field of resin curing agent technology, specifically to an electro-epoxy resin curing agent and its preparation method. Background Technology

[0002] With the development of high-frequency electronic technologies such as 5G communication and millimeter-wave radar, electronic packaging materials have stringent requirements for dielectric properties. Epoxy resin has become a core substrate due to its excellent mechanical strength and insulation properties, but its dielectric constant of 4.0-5.5 and dielectric loss >0.02 at 1MHz are insufficient to meet the requirements of high-frequency signal transmission, necessitating modification and optimization through curing agents.

[0003] Existing curing agent technologies for reducing dielectric constant have significant limitations: fluorinated curing agents (such as CN108752213A) reduce the dielectric constant to 3.8-4.2, but the fluorine element leads to poor compatibility with epoxy resins, resulting in a 15%-20% decrease in the tensile strength of the cured product; siloxane-modified amine curing agents (such as US9873826B2) have a dielectric constant of 3.5-4.0, but lower the glass transition temperature (Tg) to below 120℃, making them unsuitable for high-temperature conditions; porous curing agents (such as CN110591985A) have a dielectric constant as low as 2.8-3.2, but the micropores damage mechanical properties, reducing impact strength by more than 30%, and exhibiting large performance fluctuations.

[0004] The existing technology has three major contradictions: First, there is an imbalance between dielectric and mechanical properties. When the fluorine content exceeds 30wt%, the viscosity increases by more than 50% within 24 hours after the curing agent is mixed with the epoxy resin, making processing difficult. Second, there is a conflict between process and performance. In order to pursue ultra-low dielectric constant, high temperature and high pressure reaction is used, which increases energy consumption and darkens the color of the curing agent, affecting application. Third, there is insufficient customization. Simultaneously meeting the requirements of dielectric constant <3.0 and Tg>180℃ requires complex processes, which increases costs by more than 40%.

[0005] Furthermore, high-performance, low-dielectric curing agents rely on imports, costing as much as 800-1200 yuan / kg, with long delivery cycles; some products release toxic gases and do not comply with environmental regulations. Therefore, developing curing agents that combine low dielectric (<3.5), high heat resistance (Tg>150℃), good compatibility, and industrial feasibility has become key to breaking through the bottleneck of high-frequency materials. Summary of the Invention

[0006] Technical problems to be solved

[0007] In view of the above-mentioned shortcomings of the prior art, the present invention provides an electro-epoxy resin curing agent and its preparation method, which can effectively solve the problems in the prior art.

[0008] Technical solution

[0009] This invention provides an electro-epoxy resin curing agent and its preparation method, comprising the following components: amine compound A: selected aliphatic polyamine or aromatic polyamine, 30-60 parts by weight; fluorinated monomer B: selected trifluoromethyl acrylate or fluorinated epoxy resin, 10-30 parts by weight; modifier C: siloxane oligomer or cage-type silsesquioxane, weighed 5-20 parts by weight; catalyst D: 0.5-1 parts by weight.

[0010] Furthermore, the amine compound A molecule contains 2-4 active amino groups, specifically at least one of ethylenediamine, diethylenetriamine, m-phenylenediamine, or 4,4'-diaminodiphenylmethane, and the fluorine content in the fluorinated monomer B is 15-30 wt%, preferably trifluoroethyl acrylate or hexafluorobisphenol A diglycidyl ether, and the fluorine content is controlled at 20-25 wt%.

[0011] Furthermore, the number average molecular weight of the modifier C is 500-2000, and the catalyst D is selected from boron trifluoride diethyl ether complex, imidazole compound, or organotin compound.

[0012] A method for preparing an electro-epoxy resin curing agent, the method comprising:

[0013] S1: Initial reaction system setup: Add 30-60 parts by weight of amine compound A and 0.1-2 parts by weight of catalyst D to the reaction vessel, turn on the stirrer, and simultaneously heat the reaction vessel to 50-80℃ using a heating device. Keep stirring at this temperature to ensure that amine compound A and catalyst D are fully and evenly mixed.

[0014] S2: Fluorine-containing monomer dropwise addition and reaction: Add 10-30 parts by weight of the weighed fluorine-containing monomer B into the dropping funnel. Under the conditions of maintaining the temperature inside the reactor at 50-80℃ and nitrogen protection, start adding the fluorine-containing monomer B dropwise into the reactor. Control the dropping rate and keep the dropping time at 0.5-2 hours. Adjust the heating device to raise the temperature inside the reactor to 60-90℃. Continue stirring and reacting at this temperature for 2-4 hours.

[0015] S3: Addition and reaction of modifier: Add 5-20 parts by weight of modifier C to the reactor, then raise the temperature inside the reactor to 100-120℃, maintain the stirring rate at 200-400r / min, and continue the reaction for 1-3 hours to allow modifier C to fully combine and react with the reaction system.

[0016] S4: Product processing: After the reaction is completed, turn off the heating device and stop the nitrogen gas supply, and let the material in the reactor cool naturally to room temperature; the cooled material is the low dielectric epoxy resin curing agent, which can be collected and stored in a suitable container.

[0017] Furthermore, after product processing, the product's performance is tested. The resin curing agent and bisphenol A epoxy resin are mixed evenly at a mass ratio of 1:5, then cured at 120℃ for 2 hours, and then cured at 150℃ for 1 hour. The dielectric constant (1MHz) of the cured product is tested according to GB / T 1409-2006 standard, and its value should be in the range of 2.5-3.5; the dielectric loss tangent value is ≤0.005; at the same time, the tensile strength of the cured product is tested, and it should reach 40-50MPa.

[0018] Furthermore, in step S1, after amine compound A and catalyst D by weight are added to the reactor, nitrogen gas is introduced into the reactor at a certain flow rate (e.g., 100-200 mL / min) to remove air from the reactor and to use nitrogen gas as a protective gas.

[0019] Furthermore, in step S1, the stirring speed of the stirrer is 200-400 r / min, and the reaction vessel is stirred for 10-20 minutes.

[0020] Furthermore, the stirring rate of the reactor in S2 is 200-400 r / min.

[0021] Beneficial effects

[0022] In this invention, highly electronegative fluorine atoms are introduced into the molecular structure through the synergistic effect of fluorine-containing monomer B and amine compound A, which can significantly reduce the polarity of the curing agent and the epoxy resin system after curing. Experimental data show that the dielectric constant of the cured product at a frequency of 1MHz is as low as 2.5-3.5, which is about 30%-40% lower than that of traditional curing agents (dielectric constant 4.0-5.0). At the same time, the dielectric loss tangent is ≤0.005, which is much lower than that of traditional products (>0.02). This characteristic enables it to effectively reduce energy loss and signal delay in high-frequency signal transmission, perfectly meeting the core material requirements of high-frequency electronic fields such as 5G / 6G communication base stations, millimeter-wave radar, and high-speed printed circuit boards, and solving the problem of low signal transmission efficiency caused by insufficient dielectric properties of traditional curing agents.

[0023] Furthermore, the selected catalyst D (such as boron trifluoride diethyl ether complex) can precisely control the reaction process, increasing the conversion rate of amine compounds with fluorinated monomers to over 95%, significantly higher than the system without catalyst (conversion rate 70%-80%). Simultaneously, the temperature and time parameters for each reaction stage were optimized through orthogonal experiments, effectively avoiding side reactions (such as oxidation of amines and self-polymerization of fluorinated monomers). The product molecular weight distribution index (PDI) is controlled at 1.2-1.5, exhibiting high molecular structural uniformity. In addition, the curing agent demonstrates excellent storage stability; under sealed conditions at 25°C for 6 months, the viscosity change rate is ≤5%, with no stratification or precipitation, meeting the full-cycle stability requirements of "preparation-storage-use" in industrial production. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0025] Figure 1 This is a flowchart illustrating the structure of the present invention. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0027] The present invention will be further described below with reference to embodiments.

[0028] Example 1: An electro-epoxy resin curing agent, see attached... Figure 1 It includes the following components: Amine compound A: selected aliphatic or aromatic polyamine, 30 parts by weight; Fluorinated monomer B: selected trifluoromethyl acrylate or fluorinated epoxy resin, 10 parts by weight; Modifier C: siloxane oligomer or cage-type silsesquioxane, 5 parts by weight; Catalyst D: 0.5 parts by weight.

[0029] The amine compound A molecule contains two active amino groups, specifically at least one of ethylenediamine, diethylenetriamine, m-phenylenediamine or 4,4'-diaminodiphenylmethane. The fluorine content in the fluorinated monomer B is 15 wt%, preferably trifluoroethyl acrylate or hexafluorobisphenol A diglycidyl ether, and the fluorine content is controlled at 20 wt%.

[0030] The number average molecular weight of the modifier C is 500-2000, and the catalyst D is selected from boron trifluoride diethyl ether complex, imidazole compound or organotin compound.

[0031] Example 2: An electro-epoxy resin curing agent, comprising the following components: Amine compound A: selected from aliphatic or aromatic polyamines, 60 parts by weight; Fluorinated monomer B: selected from trifluoromethyl acrylate or fluorinated epoxy resin, 30 parts by weight; Modifier C: siloxane oligomer or cage-type silsesquioxane, 20 parts by weight; Catalyst D: 1 part by weight.

[0032] The amine compound A contains four active amino groups, specifically at least one of ethylenediamine, diethylenetriamine, m-phenylenediamine, or 4,4'-diaminodiphenylmethane. The fluorine content of the fluorinated monomer B is 30 wt%, preferably trifluoroethyl acrylate or hexafluorobisphenol A diglycidyl ether, and the fluorine content is controlled at 25 wt%. The number average molecular weight of the modifier C is 2000, and the catalyst D is selected from boron trifluoride ether complex, imidazole compounds, or organotin compounds.

[0033] By synergistically combining fluorine-containing monomer B and amine compound A, highly electronegative fluorine atoms are introduced into the molecular structure, significantly reducing the polarity of the curing agent and the cured epoxy resin system. Experimental data show that the dielectric constant of the cured product at 1MHz is as low as 2.5-3.5, a reduction of approximately 30%-40% compared to traditional curing agents (dielectric constant 4.0-5.0); simultaneously, the dielectric loss tangent is ≤0.005, far lower than traditional products (>0.02). This characteristic effectively reduces energy loss and signal delay during high-frequency signal transmission, perfectly meeting the core material requirements of high-frequency electronic fields such as 5G / 6G communication base stations, millimeter-wave radar, and high-speed printed circuit boards, solving the problem of low signal transmission efficiency caused by insufficient dielectric properties of traditional curing agents. While reducing the dielectric constant, this invention constructs a "fluorine-silicon synergistic enhancement" molecular structure by introducing modifier C (siloxane oligomer or cage-like silsesquioxane). The flexible segments of siloxanes can alleviate internal stress in the system, while the rigid cage-like structure of cage-like silsesquioxanes can enhance the rigidity of the material. The combination of the two results in a tensile strength of 40-50 MPa for the cured product, which is 15-20% higher than that of traditional amine curing agents, while maintaining an elongation at break of 5%-8%, thus combining high strength with a certain degree of toughness. In addition, the selection of aromatic polyamines (such as m-phenylenediamine) further enhances the rigidity and heat resistance of the molecular chain, and the glass transition temperature (Tg) of the cured product can reach 150-180℃. It can maintain structural stability at high temperatures and overcome the technical pain point of fluorinated materials, which often suffer from decreased mechanical properties due to excessive flexibility of the molecular chain.

[0034] Example 3: A method for preparing an electro-epoxy resin curing agent, the method being used to realize a resin curing agent, the method comprising,

[0035] S1: Initial reaction system setup: Add 30 parts by weight of amine compound A and 0.1 parts by weight of catalyst D to the reactor. Turn on the stirrer and simultaneously heat the reactor to 50°C using a heating device. Maintain stirring at this temperature to ensure thorough and uniform mixing of amine compound A and catalyst D. After adding amine compound A and catalyst D to the reactor, introduce nitrogen gas into the reactor at a certain flow rate (e.g., 100-200 mL / min) to purge air from the reactor and use nitrogen as a protective gas. The stirring speed of the stirrer is 200-400 r / min, and the reactor is stirred for 10-20 minutes.

[0036] S2: Fluorine-containing monomer addition and reaction: Add 10 parts by weight of fluorine-containing monomer B to the dropping funnel. Under the conditions of maintaining the temperature inside the reactor at 50℃ and nitrogen protection, start adding fluorine-containing monomer B dropwise into the reactor. Control the dropping rate to keep the dropping time at 0.5 hours to ensure that fluorine-containing monomer B is added evenly to the reaction system. After the dropping is completed, adjust the heating device to raise the temperature inside the reactor to 60℃. Continue stirring the reaction at this temperature for 2 hours to allow amine compound A to react fully with fluorine-containing monomer B. The stirring rate of the reactor in S2 is 200-400 r / min.

[0037] S3: Addition and reaction of modifier: After the reaction reaches the above time, add 5 parts by weight of modifier C to the reaction vessel, then raise the temperature inside the reaction vessel to 100℃, maintain the stirring rate at 200r / min, and continue the reaction for 1 hour to allow modifier C to fully combine and react with the reaction system.

[0038] S4: Product processing: After the reaction is complete, turn off the heating device and stop the nitrogen supply. Allow the material in the reactor to cool naturally to room temperature. The cooled material is the low-dielectric epoxy resin curing agent, which can be collected and stored in a suitable container.

[0039] After product treatment, the product's performance is tested. The resin curing agent and bisphenol A epoxy resin are mixed evenly at a mass ratio of 1:5, then cured at 120℃ for 2 hours, and then cured at 150℃ for 1 hour. The dielectric constant (1MHz) of the cured product is tested according to GB / T1409-2006 standard, and its value should be in the range of 2.5-3.5; the dielectric loss tangent value is ≤0.005; at the same time, the tensile strength of the cured product is tested, and it should reach 40-50MPa.

[0040] Example 4: S1: Initial reaction system setup: 60 parts by weight of amine compound A and 2 parts by weight of catalyst D were added to the reactor. The stirrer was turned on, and the reactor was heated to 80°C using a heating device. Stirring was maintained at this temperature to ensure that amine compound A and catalyst D were thoroughly mixed. After adding amine compound A and catalyst D to the reactor, nitrogen gas was introduced into the reactor at a certain flow rate (e.g., 200 mL / min) to remove air from the reactor and to use nitrogen as a protective gas. The stirring speed of the stirrer was 400 r / min, and the reactor was stirred for 20 minutes.

[0041] S2: Fluorine monomer addition and reaction: Add 30 parts by weight of fluorine monomer B to the dropping funnel. Under the conditions of maintaining the temperature inside the reactor at 80°C and nitrogen protection, start adding fluorine monomer B dropwise into the reactor. Control the dropping rate and keep the dropping time at 2 hours to ensure that fluorine monomer B can be added evenly into the reaction system. After the dropping is completed, adjust the heating device to raise the temperature inside the reactor to 90°C. Continue stirring the reaction at this temperature for 4 hours to allow amine compound A and fluorine monomer B to react fully.

[0042] S3: Addition and reaction of modifier: After the reaction reaches the above time, add 20 parts by weight of modifier C to the reaction vessel, then raise the temperature inside the reaction vessel to 120°C, maintain the stirring rate at 400 r / min, and continue the reaction for 3 hours to allow modifier C to fully combine and react with the reaction system.

[0043] S4: Product Processing: After the reaction is complete, turn off the heating device and stop the nitrogen supply. Allow the material in the reactor to cool naturally to room temperature. The cooled material is the low-dielectric epoxy resin curing agent, which can be collected and stored in a suitable container.

[0044] After product processing, the product's performance is tested. The resin curing agent and bisphenol A epoxy resin are mixed evenly at a mass ratio of 1:5, then cured at 120℃ for 2 hours, and then cured at 150℃ for 1 hour. The dielectric constant (1MHz) of the cured product is tested according to GB / T1409-2006 standard, and its value should be in the range of 2.5-3.5; the dielectric loss tangent value is ≤0.005; at the same time, the tensile strength of the cured product is tested, and it should reach 40-50MPa.

[0045]

[0046]

[0047]

[0048] Table 1

[0049] All performance data of the curing agent of this invention are derived from products manufactured according to the aforementioned preparation method and process parameters, and obtained through testing according to relevant standards; the data of traditional curing agents are the average test values ​​of common similar products on the market. This table can intuitively reflect the advantages of the curing agent of this invention in terms of dielectric properties, mechanical properties, processing performance, and economy, and meets the needs of relevant testing and comparative analysis.

[0050] The catalyst D in this invention (such as boron trifluoride diethyl ether complex) can precisely control the reaction process, increasing the conversion rate of amine compounds with fluorinated monomers to over 95%, which is significantly higher than the system without catalyst (conversion rate of 70%-80%). Simultaneously, the temperature and time parameters for each reaction stage are optimized through orthogonal experiments, effectively avoiding side reactions (such as oxidation of amines and self-polymerization of fluorinated monomers). The product molecular weight distribution index (PDI) is controlled at 1.2-1.5, exhibiting high molecular structural uniformity. Furthermore, the curing agent exhibits excellent storage stability. Under sealed conditions at 25°C for 6 months, the viscosity change rate is ≤5%, with no stratification or precipitation, meeting the full-cycle stability requirements of "preparation-storage-use" in industrial production. By adjusting the fluorine content (15-30 wt%) of the fluorinated monomer B, the dielectric constant can be controlled as needed (e.g., a dielectric constant as low as 2.8 with 25 wt% fluorine content, and approximately 3.5 with 15 wt% fluorine content). Changing the type of modifier C (e.g., using aminosiloxane to enhance adhesion to metal substrates) can adapt to the specific needs of different application scenarios. This modular design allows the curing agent to be quickly customized according to downstream customer needs, such as developing a low-modulus version (tensile modulus reduced to 2.5-3.0 GPa) for flexible electronic devices, or an ultra-high Tg version (Tg≥200°C) for high-temperature environments, greatly enhancing the technology's potential for industrial application.

[0051] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the protection scope of the technical solutions of the embodiments of the present invention.

Claims

1. An electro-epoxy resin curing agent and its preparation method, characterized in that, The product includes the following components: Amine compound A: 30-60 parts by weight of aliphatic or aromatic polyamine; Fluorinated monomer B: 10-30 parts by weight of acrylate or fluorinated epoxy resin containing trifluoromethyl; Modifier C: 5-20 parts by weight of siloxane oligomer or cage-type silsesquioxane; Catalyst D: 0.5-1 parts by weight.

2. The electro-epoxy resin curing agent and its preparation method according to claim 1, characterized in that, The amine compound A molecule contains 2-4 active amino groups, specifically at least one of ethylenediamine, diethylenetriamine, m-phenylenediamine or 4,4'-diaminodiphenylmethane. The fluorine content in the fluorinated monomer B is 15-30 wt%, preferably trifluoroethyl acrylate or hexafluorobisphenol A diglycidyl ether, and the fluorine content is controlled at 20-25 wt%.

3. The electro-epoxy resin curing agent according to claim 1, characterized in that, The number average molecular weight of the modifier C is 500-2000, and the catalyst D is selected from boron trifluoride diethyl ether complex, imidazole compound or organotin compound.

4. A method for preparing an electro-epoxy resin curing agent, characterized in that, This preparation method is used to realize the resin curing agent of any one of claims 1-3, and the preparation method includes, S1: Initial reaction system setup: Add 30-60 parts by weight of amine compound A and 0.1-2 parts by weight of catalyst D to the reaction vessel, turn on the stirrer, and simultaneously heat the reaction vessel to 50-80℃ using a heating device. Keep stirring at this temperature to ensure that amine compound A and catalyst D are fully and evenly mixed. S2: Fluorine-containing monomer dropwise addition and reaction: Add 10-30 parts by weight of the weighed fluorine-containing monomer B into the dropping funnel. Under the conditions of maintaining the temperature inside the reactor at 50-80℃ and nitrogen protection, start adding the fluorine-containing monomer B dropwise into the reactor. Control the dropping rate and keep the dropping time at 0.5-2 hours. Adjust the heating device to raise the temperature inside the reactor to 60-90℃. Continue stirring and reacting at this temperature for 2-4 hours. S3: Addition and reaction of modifier: Add 5-20 parts by weight of modifier C to the reactor, then raise the temperature inside the reactor to 100-120℃, maintain the stirring rate at 200-400r / min, and continue the reaction for 1-3 hours to allow modifier C to fully combine and react with the reaction system. S4: Product processing: After the reaction is completed, turn off the heating device and stop the nitrogen gas supply, and let the material in the reactor cool naturally to room temperature; the cooled material is the low dielectric epoxy resin curing agent, which can be collected and stored in a suitable container.

5. The method for preparing an electro-epoxy resin curing agent according to claim 4, characterized in that, After product processing, the product's performance is tested. The resin curing agent and bisphenol A epoxy resin are mixed evenly at a mass ratio of 1:5, then cured at 120℃ for 2 hours, and then cured at 150℃ for 1 hour. The dielectric constant (1MHz) of the cured product is tested according to GB / T 1409-2006 standard, and its value should be in the range of 2.5-3.5; the dielectric loss tangent value is ≤0.005; at the same time, the tensile strength of the cured product is tested, and it should reach 40-50MPa.

6. The method for preparing an electro-epoxy resin curing agent according to claim 4, characterized in that, In step S1, after amine compound A and catalyst D by weight are added to the reactor, nitrogen gas is introduced into the reactor at a certain flow rate (e.g., 100-200 mL / min) to remove air from the reactor and to use nitrogen gas as a protective gas.

7. The method for preparing an electro-epoxy resin curing agent according to claim 4, characterized in that, In step S1, the stirring speed of the stirrer is 200-400 r / min, and the reaction vessel is stirred for 10-20 minutes.

8. The method for preparing an electro-epoxy resin curing agent according to claim 4, characterized in that, The stirring rate of the reactor in S2 is 200-400 r / min.

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