Preparation method of heat-resistant high-filling epoxy copper clad plate material

Abstract

The application discloses a preparation method of a heat-resistant high-filling epoxy copper-clad plate material and belongs to the technical field of copper plate materials. After mixing boron nitride and carbon nanotubes, ball milling is assisted to peel and modify the surface by using glycine to obtain amino acid modified hybrid fillers; a trifunctional bio-based epoxy resin is synthesized by using trans-resveratrol as raw material; a multifunctional benzoic acid ester type active ester curing agent is prepared by reacting 1,6-dihydroxynaphthalene with benzoyl chloride. The amino acid modified hybrid fillers, the trifunctional epoxy resin, the multifunctional benzoic acid ester type curing agent and 2-ethyl-4-methyl imidazole are prepared into a high-filling impregnation liquid, a low-dielectric glass fiber cloth is impregnated, pre-cured, and then heat-pressed and cured in a vacuum condition in multiple temperature rising stages to obtain the copper-clad plate. The application effectively solves the technical problems of insufficient heat dissipation and large signal loss in the high-frequency and high-speed application of the traditional epoxy copper-clad plate.

Description

Technical Field

[0001] This invention belongs to the field of copper plate material technology, specifically, it relates to a method for preparing a heat-resistant, high-filler epoxy copper-clad laminate material. Background Technology

[0002] Copper-clad laminate (CCL), as a core material for printed circuit boards (PCBs), occupies an irreplaceable strategic position in the modern electronic information industry. High-frequency, high-speed epoxy CCL is an electronic material composed of epoxy resin, fiberglass cloth, inorganic fillers, and copper foil in a specific ratio. Its dielectric, thermal, and mechanical properties directly determine the PCB's performance in high-speed signal transmission and thermal management. This material is primarily used as a key substrate for 5G / 6G communication equipment, millimeter-wave automotive radar, AI server backplanes, high-speed switches, and high-end consumer electronics products. It can significantly reduce signal transmission loss, improve system heat dissipation efficiency, and enhance long-term reliability, thereby supporting the development of national strategic emerging industries such as data centers, autonomous driving, and high-end computing.

[0003] However, the performance of traditional epoxy copper clad laminate materials remains significantly limited under extreme high-frequency and high-speed operating conditions, making it difficult to meet the increasingly stringent requirements of the modern electronics industry for comprehensive material performance. First, after curing traditional bisphenol A type epoxy with amine or phenolic curing agents, a large number of polar secondary hydroxyl groups remain in the network, resulting in a dielectric constant typically between 4.2 and 4.8, and a dielectric loss factor as high as 0.015 to 0.025 (@10GHz). This causes severe signal attenuation, impedance discontinuities, and crosstalk problems in the millimeter-wave band. Second, the glass transition temperature of these materials is mostly between 130 and 180°C, and their thermal conductivity is generally below 0.5 W / m·K. In applications such as high-power AI chips and 5G massive MIMO antennas, their heat dissipation capacity is severely insufficient, easily leading to localized overheating, delamination, and reliability failure. Third, the high filler content of traditional materials easily leads to filler agglomeration, a sharp increase in processing viscosity, and interface defects, further deteriorating peel strength and flexural properties.

[0004] To address the aforementioned issues, researchers both domestically and internationally have conducted extensive research on modification technologies, primarily focusing on traditional process routes such as modification of highly filled inorganic fillers, optimization of resin molecular structures, development of novel curing agents, and surface treatment. While highly filled silica or alumina can reduce density (Dk) and improve rigidity, dispersion becomes difficult when the filler content exceeds 60 wt%, resulting in poor system leveling and stress concentration points after curing. The interfacial bonding of fillers modified with traditional silane coupling agents lacks stability under high-temperature and humid conditions. Regarding resin optimization, although fluorine-containing or liquid crystal structures have been introduced, they are costly and have poor process compatibility. While reactive ester curing systems can reduce polar groups, a systematic solution for synergy with highly filled nanomaterials has not yet been developed. Furthermore, single-dimensional fillers struggle to construct efficient three-dimensional thermal pathways, and nanofiller agglomeration and interfacial phonon scattering remain prominent issues.

[0005] In summary, although some progress has been made in the research on the modification of epoxy copper clad laminates, the following core issues still need to be addressed: First, there is a lack of a systematic solution that can simultaneously achieve "ultra-low Dk / Df, high heat resistance, high thermal conductivity, and excellent processability"; second, the dispersion stability and low interfacial impedance mechanism of nano-hybrid fillers in highly filled epoxy matrix are still unclear; third, the multi-scale structural regulation of resin-curing agent-filler has not been effectively coupled, making it difficult to exert a synergistic strengthening effect; fourth, traditional processes lack the ability to optimize the microstructure of materials at multiple levels, from molecular networks to nano-thermal conductive pathways. Therefore, developing a new heat-resistant, highly filled epoxy copper clad laminate technology that can break through performance limits, achieve multi-scale synergistic modification, and possess both excellent comprehensive performance and good process adaptability is of great strategic significance and broad application prospects for promoting my country's high-end electronic manufacturing and enhancing the self-sufficiency of key components for 5G / 6G and artificial intelligence. Summary of the Invention

[0006] To address the problems of high dielectric constant and dielectric loss (Dk typically 4.2-4.8, Df 0.015-0.025@10GHz), low glass transition temperature (mostly 130-180℃), low thermal conductivity (<0.5W / m·K), easy agglomeration of fillers leading to a sharp increase in processing viscosity and a decrease in peel strength when using traditional epoxy copper clad laminate materials in 5G / 6G high-frequency and high-speed applications, this invention provides a method for preparing a heat-resistant, high-filler epoxy copper clad laminate material reinforced with nano-hybrid fillers.

[0007] The present invention adopts the following technical solution: a method for preparing a heat-resistant high-filled epoxy copper-clad laminate material, which, by mass, includes the following steps: (1) mixing 60-100 parts of boron nitride and 3-15 parts of carbon nanotubes at a mass ratio of (20-60):1, adding 0.2-3.0 times the total mass of glycine (CAS No.: 56-40-6), ball milling and drying to obtain amino acid modified thermally conductive and insulating hybrid filler; (2) feeding trans-resveratrol (CAS No.: 501-36-0) and epichlorohydrin (CAS No.: 106-89-8) at a molar ratio of 1:(8-20), adding 0.5-5.0% of the mass of trans-resveratrol of tetrabutylammonium bromide (CAS No.: 1643-19-2), making the system alkaline after the first reaction and reacting a second time to obtain trifunctional epoxy resin; (3) mixing 1,6-dihydroxynaphthalene (CAS No.: 575-44- 0) Dissolve in anhydrous dichloromethane at 8-15 times its mass, add 1-5% of triethylamine (CAS No.: 121-44-8) and 0.1-1% of 4-dimethylaminopyridine (CAS No.: 1122-58-3) by mass, then add benzoyl chloride (CAS No.: 98-88-4) dropwise to obtain a multifunctional benzoic acid ester type curing agent; (4) 55-85 parts of amino acid modified thermally conductive and insulating hybrid filler, trifunctional epoxy resin 10-35 parts, 3-20 parts of multifunctional benzoic acid ester curing agent, 0.05-1.0 parts of 2-ethyl-4-methylimidazole (CAS No.: 931-36-2), N,N-dimethylformamide (CAS No.: 68-12-2) was added to adjust the viscosity, and the foam was removed to obtain the impregnation solution; (5) the low dielectric constant glass fiber cloth was impregnated with the above impregnation solution and pre-cured to obtain a prepreg; (6) the prepreg was stacked with copper foil and hot-pressed to obtain the prepreg.

[0008] Preferably, the ball milling process in step (1) is as follows: place the ball in a milling jar and use ZrO2 balls to mill at a speed of 200-600 rpm for 2-8 hours.

[0009] Preferably, the ball-to-material ratio during ball milling in step (1) is 10:1-20:1; the drying method in step (1) is vacuum drying, the drying temperature is 40-100℃, and the drying time is 12-24h.

[0010] Preferably, the parameters for the first reaction in step (2) are as follows: reaction temperature 60-85℃, reaction time 1-8h; and the parameters for the second reaction in step (2) are as follows: reaction temperature 60-85℃, reaction time 0.5-6h.

[0011] Preferably, in step (2), an aqueous solution of sodium hydroxide (CAS No.: 1310-73-2) is added dropwise to make the system alkaline; after the second reaction in step (2), the system is filtered to remove salt, extracted with ethyl acetate, separated, and removed by vacuum distillation to remove excess epichlorohydrin.

[0012] Preferably, the molar ratio between 1,6-dihydroxynaphthalene and benzoyl chloride in step (3) is 1:(2.0-2.5); the method of adding benzoyl chloride in step (3) is as follows: benzoyl chloride is slowly added at a rate of 0.2-1.0 mL / min at 0-10℃, and the temperature is controlled for 1-4 h after the addition is completed, and then the temperature is raised to 10-30℃ to continue the reaction for 2-24 h.

[0013] Preferably, step (3) after adding benzoyl chloride further includes the steps of filtration to remove salt, washing with dilute hydrochloric acid, water, and saturated sodium bicarbonate solution in sequence, drying the organic phase, rotary evaporation, and recrystallization with ethanol. The specific operation is as follows: filter to remove salt using a Buchner funnel and medium-speed qualitative filter paper with a pore size of 10-20 μm, wash with 1-2 mol / L dilute hydrochloric acid, water, and saturated sodium bicarbonate solution three times each, dry the organic phase with 5-15 g of anhydrous sodium sulfate at room temperature for 2-6 h, then remove the solvent by rotary evaporation at 30-50 °C and a vacuum degree of -0.08--0.1 MPa, add 20-50 mL of anhydrous ethanol to the residue and heat to reflux to dissolve, slowly cool to 0-5 °C to crystallize for 2-4 h, wash twice with ice-cold ethanol, and dry under vacuum at 60-80 °C for 4-12 h.

[0014] Preferably, the viscosity at 25°C in step (4) is 300-3000 mPa·s; the degassing parameters in step (4) are as follows: vacuum degree ≤ 5 kPa, degassing for 5-60 min.

[0015] Preferably, the pre-curing parameters in step (5) are as follows: the first stage is heated at 85-110℃ for 1-6 min, the second stage is heated at 115-145℃ for 3-10 min, and the third stage is heated at 150-180℃ for 2-10 min, with a total time of 2-30 min.

[0016] Preferably, in step (6), the vacuum degree of hot pressing curing is ≤200Pa and the pressure is 1-8MPa. The heating program of hot pressing curing is as follows: the first stage is 80-120℃ and the heat is maintained for 0.5-2h; the second stage is 140-180℃ and the heat is maintained for 0.5-2h; the third stage is 200-240℃ and the heat is maintained for 1-3h; and the fourth stage is 250-270℃ and the heat is maintained for 0.5-2h.

[0017] Compared with existing technologies, the present invention has the following significant advantages: The present invention uses glycine to ball-mill-assisted simultaneous exfoliation and surface amphiphilic modification of boron nitride and carbon nanotubes. The amino and carboxyl functional groups in the glycine molecule form strong hydrogen bonds and chemical bonds with the epoxy groups in the epoxy resin and the ester groups in the curing agent, respectively, which greatly reduces the filler-matrix interface thermal resistance (ITR) and phonon scattering. At the same time, carbon nanotubes, as a "thermal bridge", effectively bridge the two-dimensional nanosheets, and construct a continuous three-dimensional thermally conductive network in situ under high filling amount (55-85 parts), realizing efficient long-distance phonon transmission. Furthermore, the trifunctional rigid bio-based epoxy resin synthesized from trans-resveratrol provides a high crosslinking density and a low-polarity aromatic backbone structure. Meanwhile, the 1,6-dihydroxynaphthyl polyfunctional benzoate-type active ester curing agent undergoes a transesterification ring-opening reaction with the epoxy resin under the catalysis of 2-ethyl-4-methylimidazolium (instead of a traditional addition reaction), which completely avoids the formation of high-polarity secondary hydroxyl groups and forms a curing network with low-polarity ester bonds as the main chain. This greatly suppresses dipole orientation polarization and ion polarization loss at the molecular level. The multi-scale synergistic effect of the above-mentioned nano-interface optimization, molecular network design, and macro-filler network construction enables the copper-clad laminate prepared by this invention to possess ultra-high heat resistance (Tg>220℃), excellent thermal conductivity (2.5-3.2W / m·K), extremely low dielectric constant and loss (Dk3.0-3.2, Df<0.003@10GHz), high peel strength (>1.35N / mm), and excellent resistance to humid heat (T-288>50min, water absorption rate<0.16%). This completely solves the core technical problems of traditional bisphenol A type epoxy / amine (or phenol) curing systems in 5G / 6G high-frequency and high-speed applications, such as difficult heat dissipation, severe signal attenuation, and poor high-filler processability. It provides a high-performance material solution for fields such as millimeter-wave radar, high-speed AI server backplanes, and high-frequency and high-speed printed circuit boards. Attached Figure Description

[0018] Figure 1 The image shows the infrared spectrum of the amino acid-modified thermally conductive and insulating hybrid filler prepared in Example 1.

[0019] Figure 2 This is the infrared spectrum of the trifunctional epoxy resin prepared in Example 1.

[0020] Figure 3 The image shows the infrared spectrum of the multifunctional benzoate curing agent prepared in Example 1.

[0021] Figure 4 This is a sample image of the impregnation solution prepared in Example 1. Detailed Implementation

[0022] The present invention will now be described in detail through specific embodiments. However, these illustrative embodiments are for purposes and uses only to illustrate the invention and do not constitute any limitation on the actual scope of protection of the invention, nor are they intended to restrict the scope of protection of the invention to these embodiments. For parameter ranges not mentioned, intermediate values ​​are selected. Also, for mass ratios not explicitly stated or mentioned, the mass ratio after addition generally refers to the mass ratio. Furthermore, in the present invention, the unit of mass is grams (g).

[0023] Example 1

[0024] The preparation method of heat-resistant high-filler epoxy copper clad laminate material includes the following steps: (1) Preparation of amino acid modified thermally conductive and insulating hybrid filler: Weigh 80g boron nitride (average flake diameter 1-2μm, thickness 10-50nm, purity >99%) and 3g carbon nanotubes (diameter 20-50nm, length 1-5μm, purity >99%, mass ratio 26.7:1), add 1.0 times the total mass of glycine (83g), and place it in a planetary ball mill (model: QM). -3SP2 (Nanjing Nanda Instrument Factory) In a jar, ZrO2 balls (5mm diameter, ball-to-material ratio 15:1) were used for ball milling at 400 rpm for 4 hours to assist in exfoliation and surface modification. After ball milling, the filler was washed five times with anhydrous ethanol until neutral (pH=7), and then placed in a vacuum drying oven (model: DZF-6050, Beijing Lida Instrument) at 60℃ for 12 hours to obtain an amino acid-modified thermally conductive and insulating hybrid filler containing both amino and carboxyl functional groups (yield 78g). Figure 1 As shown. (2) Preparation of trifunctional epoxy resin: 5.0g of trans-resveratrol and 24.3g of epichlorohydrin (molar ratio 1:12) were added, and 0.1g of tetrabutylammonium bromide (as a phase transfer catalyst) of 2.0% of trans-resveratrol were added. The mixture was placed in a three-necked round-bottom flask and reacted at 75℃ for 4h under a mechanical stirrer (model: JJ-1, Jiangsu Jiadabo Instruments). Then, 12g of 20wt% sodium hydroxide aqueous solution was slowly added dropwise, with the dropping rate controlled at 1m. The system pH was adjusted to 10⁻¹¹ using a flow rate of L / min, and the reaction was continued for 2 hours. After the reaction, the system was filtered under reduced pressure to remove salts, and extracted three times with 200 mL of ethyl acetate (500 mL each time). The organic phase was separated and the excess epichlorohydrin was removed by vacuum distillation using a rotary evaporator (model: RE-2000E, Shanghai Youhua Instruments) at 40℃, -0.095 MPa, to obtain a trifunctional epoxy resin (yield 18.2 g, epoxy value 0.45 mol / 100 g). Figure 2As shown. (3) Preparation of polyfunctional benzoic acid ester type curing agent: 5.0g of 1,6-dihydroxynaphthalene was dissolved in 50g of anhydrous dichloromethane, and 3% of its mass of triethylamine (0.15g) and 0.5% of 4-dimethylaminopyridine (0.025g, as catalyst) were added. The mixture was placed in an ice bath and the temperature was controlled at 5℃. 9.6g of benzoyl chloride (molar ratio 1:2.2, dropping rate 0.5mL / min) was slowly added dropwise. The reaction was carried out for 2h, and then the temperature was raised to 25℃ and continued. The reaction continued for 10 hours; the phase was filtered to remove salt, and then washed three times successively with dilute hydrochloric acid (1 mol / L, 100 mL), deionized water (100 mL), and saturated sodium bicarbonate solution (100 mL). The organic phase was dried with anhydrous sodium sulfate (5 g) for 4 hours, and the solvent was removed by rotary evaporation (40℃, -0.095 MPa). The phase was recrystallized from ethanol (20 mL), filtered, and dried to obtain a polyfunctional benzoate curing agent (yield 11.3 g). Figure 3 As shown. (4) Preparation of high-filling impregnation solution: Take 70g of amino acid modified hybrid filler obtained in step (1), 20g of trifunctional epoxy resin obtained in step (2), 9.5g of polyfunctional benzoic acid ester curing agent obtained in step (3), 0.5g of 2-ethyl-4-methylimidazolium, add N,N-dimethylformamide (DMF, about 150g) to a viscosity of 1500mPa·s at 25℃ (using NDJ-8S digital viscometer, Shanghai Jieheng Instruments), degas at a vacuum of 4kPa for 20min (vacuum pump model: 2XZ-4) to obtain impregnation solution. (5) Preparation of prepreg: The low dielectric constant glass fiber cloth (D-glass 2116 type, thickness 0.105mm, surface density 104g / m²) was impregnated with the impregnation solution (impregnation speed 0.5m / min, impregnation solution temperature 25℃), and pre-cured for 12min in stages by heating in an oven (model: 101-2AB, Shanghai Yuejin Medical Electric) at 90℃ / 2min→120℃ / 5min→150℃ / 5min, so that the resin mass fraction of the prepreg was 45% (determined by drying and weighing method). (6) Preparation of copper clad laminate: Eight prepreg sheets and two low-profile electrolytic copper foils (1.0 oz thick, double-sided) were stacked together and placed in a vacuum hot press (model: QY-30, Shanghai Kemei Instruments). The copper clad laminate (1.0 mm thick) was obtained by hot pressing and curing in four stages at a vacuum of 50 Pa and a pressure of 4 MPa: 100℃ / 1h → 160℃ / 1h → 220℃ / 2h → 260℃ / 1h. After cooling to room temperature, the copper clad laminate was obtained.

[0025] Specific parameters of Examples 2-12 and Comparative Examples 1-12

[0026] The following tables are designed step-by-step, with each table showing parameters different from those in Example 1, while the remaining parameters are the same as in Example 1. The examples cover all endpoint and intermediate values ​​(correct mass ratios or molar ratios), and the parameters vary for each example. The comparative examples are based on adjustments to Example 1, using missing key components, substitutions of conventional similar components, or parameters exceeding the range, setting significant differences; therefore, the parameters differ between the comparative examples.

[0027] Table 1: Preparation parameters of amino acid modified thermally conductive and insulating hybrid filler in step (1) (Examples 1-8, units: g, rpm, h)

[0028]

[0029] Table 2: Preparation parameters of amino acid modified thermally conductive and insulating hybrid filler in step (1) (Examples 9-12 and Comparative Examples 1-8, Unit: g, rpm, h)

[0030]

[0031] Table 3: Preparation parameters of trifunctional epoxy resin in step (2) (Examples 1-8)

[0032]

[0033] Table 4: Preparation parameters of trifunctional epoxy resin in step (2) (partial adjustments to Examples 9-12 and Comparative Examples 9-12, sodium hydroxide is 20wt%)

[0034]

[0035] Table 5: Preparation parameters of polyfunctional benzoate curing agent in step (3) (Examples 1-8)

[0036]

[0037] Table 6: Preparation parameters of polyfunctional benzoate curing agent in step (3) (Examples 9-12)

[0038]

[0039] Table 7: Preparation parameters of high-filling impregnation solution in step (4) (Examples 1-12, Unit: g, mPa·s, min)

[0040]

[0041] Table 8: Preparation parameters of prepreg and copper-clad laminate in steps (5) and (6) (Examples 1-12, units: min, %, Pa, MPa, h)

[0042]

[0043] Performance testing methods: Glass transition temperature (Tg): Tg was calculated using a differential scanning calorimeter (TA Instruments Q2000) under a nitrogen atmosphere, with a heating rate of 10℃ / min and a temperature range of 25-300℃. The midpoint method was used. Thermal conductivity: Tested according to ASTM E1461 using a laser scintillation thermal conductivity meter (Netzsch LFA467), with a sample diameter of 12.7 mm and a thickness of 2 mm, at room temperature (25℃), and averaged in triplicate. Dielectric constant (Dk) and dielectric loss (Df) @10GHz: Tested according to IPC-TM-6502.5.5.9 using a vector network analyzer (Keysight E5071C), with a sample size of 50 mm × 50 mm × 1 mm and a frequency of 10 GHz. T-288 heat resistance time: According to IPC-TM-6502.4.24.1 standard, using a thermomechanical analyzer (model: TAInstrumentsQ800), maintain a constant temperature of 288℃ until delamination or deformation occurs.

[0044] Peel strength: According to IPC-TM-6502.4.8 standard, using a universal testing machine (model: Instron5967), 180° peel, peel speed 50mm / min, copper foil width 9mm. Water absorption: According to IPC-TM-6502.6.2.1 standard, after boiling in a pressure cooker (121℃, 0.1MPa) for 2 hours, dried and weighed to calculate the percentage increase in weight.

[0045] Table 9: Performance test results of Examples 1-8 (thermal performance: Tg (°C), thermal conductivity (W / m·K), Dk@10GHz, Df@10GHz)

[0046]

[0047] Table 10: Performance test results of Examples 9-12 (thermal performance: Tg (°C), thermal conductivity (W / m·K), Dk@10GHz, Df@10GHz)

[0048]

[0049] Table 11: Performance test results of Examples 1-8 (Heat-resistant mechanical parts: T-288 (min), peel strength (N / mm), water absorption (%))

[0050]

[0051] Table 12: Performance test results of Examples 9-12 (Heat-resistant mechanical parts: T-288 (min), peel strength (N / mm), water absorption (%))

[0052]

[0053] Table 13: Performance test results of comparative examples 1-8 (thermal performance: Tg (°C), thermal conductivity (W / m·K), Dk@10GHz, Df@10GHz)

[0054]

[0055] Table 14: Performance test results of comparative examples 9-12 (thermal performance: Tg (°C), thermal conductivity (W / m·K), Dk@10GHz, Df@10GHz)

[0056]

[0057] Table 15: Performance test results of comparative examples 1-8 (heat-resistant mechanical parts: T-288 (min), peel strength (N / mm), water absorption (%))

[0058]

[0059] Table 16: Performance test results of comparative examples 9-12 (heat-resistant mechanical parts: T-288 (min), peel strength (N / mm), water absorption (%))

[0060]

[0061] The test results show that the product in the example has a Tg of 228.4-244.2℃, a thermal conductivity of 2.62-3.18 W / m·K (high-filler hybrid filler improves the thermal conductivity network), Dk of 3.04-3.15, Df of 0.0019-0.0028 (low-polarity curing agent reduces losses), T-288 > 50 min, peel strength > 1.35 N / mm, and water absorption < 0.16%. A high filler ratio improves thermal conductivity and heat resistance, but increases viscosity; a low filler ratio results in a slightly lower Tg but reduced thermal conductivity. The comparative example shows significant performance degradation due to the lack of boron nitride hybridization (thermal conductivity network breakage, thermal conductivity decreases by 30-60%), replacement of urea / conventional resin (functional group mismatch, Df increases by 3-5 times), parameters that are too low (insufficient modification) or too high (agglomeration / degradation, Tg decreases by 20-50℃). In Comparative Example 3, the excessively low molar ratio of epichlorohydrin (1:5) led to incomplete epoxidation of the trans-resveratrol triphenol hydroxyl groups, resulting in a large amount of residual highly polar phenolic hydroxyl groups. This caused the dielectric loss factor Df to rise sharply to 0.0125, approaching the level of traditional bisphenol A type epoxy copper clad laminates (0.015-0.025). This further demonstrates the crucial role of the epichlorohydrin feed ratio in obtaining a low-polarity trifunctional epoxy resin structure. The above data collectively prove the necessity of the key components and parameter ranges.

[0062] The above description, in conjunction with specific embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, several simple deductions or substitutions can be made without departing from the concept of the present invention, and all such deductions or substitutions should be considered to fall within the scope of protection defined by the claims submitted herein.

Claims

1. A method for preparing a heat-resistant, highly filled epoxy copper-clad laminate material, characterized in that, The process, by mass, includes the following steps: (1) mixing 60-100 parts of boron nitride with 3-15 parts of carbon nanotubes at a mass ratio of (20-60):1, adding 0.2-3.0 times the total mass of glycine, ball milling, and drying to obtain an amino acid-modified thermally conductive and insulating hybrid filler; (2) feeding trans-resveratrol and epichlorohydrin at a molar ratio of 1:(8-20), adding 0.5-5.0% of the mass of tetrabutylammonium bromide of trans-resveratrol, making the system alkaline after the first reaction, and then reacting a second time to obtain a trifunctional epoxy resin; (3) dissolving 1,6-dihydroxynaphthalene in anhydrous dichloromethane, adding 1, 1-5% by mass of 6-dihydroxynaphthalene, triethylamine and 0.1-1% by mass of 4-dimethylaminopyridine, followed by the addition of benzoyl chloride to obtain a multifunctional benzoic acid ester type curing agent; (4) 55-85 parts of amino acid modified thermally conductive and insulating hybrid filler, 10-35 parts of trifunctional epoxy resin, 3-20 parts of multifunctional benzoic acid ester type curing agent, 0.05-1.0 parts of 2-ethyl-4-methylimidazole, N,N-dimethylformamide is added to adjust the viscosity, and degassing is performed to obtain an impregnation solution; (5) The low dielectric constant glass fiber cloth is impregnated with the above impregnation solution and pre-cured to obtain a prepreg; (6) The prepreg is laminated with copper foil and hot-pressed to obtain the prepreg.

2. The method for preparing the heat-resistant, high-filler epoxy copper-clad laminate material according to claim 1, characterized in that, The ball milling process in step (1) is as follows: Place the ball in a milling jar and use ZrO2 balls to mill at a speed of 200-600 rpm for 2-8 hours.

3. The method for preparing the heat-resistant, high-filler epoxy copper-clad laminate material according to claim 2, characterized in that, In step (1), the ball-to-material ratio during ball milling is 10:1-20:1; in step (1), the drying method is vacuum drying, the drying temperature is 40-100℃, and the drying time is 12-24h.

4. The method for preparing the heat-resistant, high-filler epoxy copper-clad laminate material according to claim 1, characterized in that, The parameters for the first reaction in step (2) are as follows: reaction temperature 60-85℃, reaction time 1-8h; the parameters for the second reaction in step (2) are as follows: reaction temperature 60-85℃, reaction time 0.5-6h.

5. The method for preparing the heat-resistant, high-filler epoxy copper-clad laminate material according to claim 1, characterized in that, In step (2), sodium hydroxide aqueous solution is added dropwise to make the system alkaline; after the second reaction in step (2), the system is filtered to remove salt, extracted with ethyl acetate, separated, and removed by vacuum distillation to remove excess epichlorohydrin.

6. The method for preparing the heat-resistant, high-filler epoxy copper-clad laminate material according to claim 1, characterized in that, In step (3), the molar ratio between 1,6-dihydroxynaphthalene and benzoyl chloride is 1:(2.0-2.5); the method of adding benzoyl chloride in step (3) is as follows: benzoyl chloride is slowly added at a rate of 0.2-1.0 mL / min at 0-10℃. After the addition is completed, the temperature is controlled for 1-4 h, and then the temperature is raised to 10-30℃ to continue the reaction for 2-24 h.

7. The method for preparing the heat-resistant, high-filler epoxy copper-clad laminate material according to claim 1, characterized in that, Step (3) after adding benzoyl chloride also includes the steps of filtration to remove salt, washing with dilute hydrochloric acid, water and saturated sodium bicarbonate solution in sequence, drying the organic phase, rotary evaporation and recrystallization with ethanol. The specific operation is as follows: filter to remove salt using a Buchner funnel and medium-speed qualitative filter paper with a pore size of 10-20 μm, wash with 1-2 mol / L dilute hydrochloric acid, water and saturated sodium bicarbonate solution three times each, dry the organic phase with 5-15 g of anhydrous sodium sulfate at room temperature for 2-6 h, then remove the solvent by rotary evaporation at 30-50 °C and vacuum degree of -0.08--0.1 MPa, add 20-50 mL of anhydrous ethanol to the residue and heat to reflux to dissolve, slowly cool to 0-5 °C to crystallize for 2-4 h, wash twice with ice-cold ethanol, and dry under vacuum at 60-80 °C for 4-12 h.

8. The method for preparing the heat-resistant, high-filler epoxy copper-clad laminate material according to claim 1, characterized in that, In step (4), the viscosity at 25℃ is 300-3000 mPa·s; the degassing parameters in step (4) are as follows: vacuum degree ≤ 5 kPa, degassing for 5-60 min.

9. The method for preparing the heat-resistant, high-filler epoxy copper-clad laminate material according to claim 1, characterized in that, The pre-curing parameters in step (5) are as follows: the first stage is heated at 85-110℃ for 1-6 min, the second stage is heated at 115-145℃ for 3-10 min, and the third stage is heated at 150-180℃ for 2-10 min, with a total time of 2-30 min.

10. The method for preparing the heat-resistant, high-filler epoxy copper-clad laminate material according to claim 1, characterized in that, In step (6), the vacuum degree of hot pressing curing is ≤200Pa and the pressure is 1-8MPa. The heating program for hot pressing curing is as follows: the first stage is 80-120℃ and the heat is maintained for 0.5-2h; the second stage is 140-180℃ and the heat is maintained for 0.5-2h; the third stage is 200-240℃ and the heat is maintained for 1-3h; and the fourth stage is 250-270℃ and the heat is maintained for 0.5-2h.

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