A high thermal conductivity epoxy resin composition for copper clad laminate and preparation method thereof

Abstract

The present invention provides a highly thermally conductive epoxy resin composition for copper-clad laminates and a preparation method thereof. This method first prepares a modified silane compound, which is then used to modify a thermally conductive filler. This improves both the dispersibility of the thermally conductive filler in the epoxy resin system and the flame retardancy of the system. Aluminum-based copper-clad laminates prepared using this epoxy resin composition exhibit excellent properties such as flexural peel strength, heat resistance, and breakdown voltage resistance.

Description

Technical Field

[0001] The invention relates to a high thermal conductivity epoxy resin composition for copper-clad laminates and a preparation method thereof, in particular to a high thermal conductivity epoxy resin composition for aluminum-based copper-clad laminates and a preparation method thereof. Background Art

[0002] With the continuous advancement of electronic technology, electronic products are becoming increasingly lightweight, thin, compact, high-density, and multifunctional. The demands for high performance, light weight, and compact size are becoming increasingly prominent in various electronic products. Ultra-thinness and high density have become the mainstream development trends in flexible circuit boards. However, as circuit boards become thinner and circuit lines become finer, the heat generated per unit area during operation increases. If this heat cannot be dissipated promptly, the reliability and service life of electronic products will decline. Therefore, the heat dissipation problem of circuit boards is attracting increasing attention. However, the thermal conductivity of traditional FR-4 copper-clad laminates is low, only 0.15-0.30W / (mK), which cannot meet the rapid heat dissipation requirements of end products. Aluminum-based copper-clad laminates, due to their excellent heat dissipation and electrical properties, have been widely used in integrated circuits, automobiles, motorcycles, office automation, high-power electrical equipment, power supply equipment, and other fields.

[0003] Aluminum-based copper-clad laminates (ACCLs) are composed of aluminum sheet, a thermally conductive insulating layer, and copper foil. In addition to the general properties of CCLs, they also offer excellent heat dissipation, dimensional stability, and good processing and electromagnetic shielding properties. The thermally conductive insulating layer, which primarily conducts heat and provides insulation, is the core technology of ACLs. It directly impacts their overall performance and is a research hotspot for high-thermal-conductivity aluminum substrates.

[0004] CN104610707A discloses a metal-based copper-clad laminate for high-power LEDs manufactured using high-performance RCC. The resin composition of the metal-based copper-clad laminate comprises completely halogen-free and phosphorus-free resins, rubber, and other components. The laminate achieves flame retardancy through a high filling amount of thermally conductive and flame-retardant fillers and resins. The laminate has good thermal conductivity and flame retardancy, high heat resistance, high moisture resistance, and a low coefficient of expansion. The thermally conductive insulating layer will not decompose during use, nor will it produce halogen- or phosphorus-containing toxic and harmful gases due to combustion, thus posing no health risk. The laminate is environmentally friendly and can be widely used in metal substrates, flexible boards, multilayer boards, and the like with heat dissipation requirements. The thermally conductive insulating layer of the metal-based copper-clad laminate prepared using the resin composition is thin and has a fine pore size, providing good thermal conductivity and flame retardancy for the lightweight, thin, compact, and integrated development of electronic products, and enabling high-density wiring.

[0005] CN105623198A discloses a high thermal conductivity resin composition and its application. This patent adds thermal conductive fillers to a bismaleimide-modified epoxy and flexible epoxy resin system to prepare a thermally conductive metal substrate. Although the board has excellent heat dissipation and heat resistance and improved flexibility, the board has a maximum peel strength of only 1.4N / mm, and it will still crack after bending, and the insulation layer has no flame retardant function.

[0006] CN107502253A discloses an adhesive for high-thermal-conductivity copper-clad aluminum substrates and its preparation method. The resulting product exhibits stable thermal conductivity and flame retardancy. This invention incorporates a large proportion of bisphenol A epoxy resin modified with an inactive metal oxide, significantly increasing the product's heat resistance. DDS, a sulfone-based curing agent, is used as the primary curing agent, resulting in a more compact molecular structure after curing, which increases the crosslinking density, heat resistance, and thermal conductivity. A large proportion of fillers, using aluminum oxide and / or aluminum nitride, improves the thermal conductivity of the material. High-purity aluminum oxide of varying particle sizes is rationally combined to increase the alumina's packing density and thus the material's thermal conductivity.

[0007] The thermally conductive insulating layer is made by adding thermally conductive fillers to a thermosetting resin matrix. Although thermosetting resins, such as epoxy, offer excellent overall performance, their thermal conductivity is very low and cannot meet heat dissipation requirements. To improve the thermal conductivity of the insulating dielectric layer, inorganic fillers with good thermal conductivity must be added. Currently, thermally conductive particles such as aluminum oxide, magnesium oxide, aluminum nitride, boron nitride, and silicon nitride are widely used. However, these thermally conductive particles suffer from uneven dispersion within the resin matrix, which in turn affects the thermal conductivity of the insulating dielectric layer. Furthermore, epoxy resin is flammable and can generate heat and combustion when heat dissipation performance is poor, posing significant challenges to its application. Summary of the Invention

[0008] To solve the above technical problems, the present invention provides a high thermal conductivity epoxy resin composition for aluminum-based copper-clad laminates and a preparation method thereof. The method first prepares a modified silane compound, and then uses the modified silane compound to modify the thermal conductive filler, thereby improving the dispersibility of the thermal conductive filler in the epoxy resin system and improving the flame retardancy of the system.

[0009] In order to achieve the above object, the present invention adopts the following technical solutions:

[0010] A high thermal conductivity epoxy resin composition for aluminum-based copper-clad laminates, wherein the composition is prepared from the following components in parts by mass:

[0011] 100 parts epoxy resin

[0012] 10-20 parts of thermoplastic rubber

[0013] 120-160 parts of modified thermal conductive filler

[0014] 5-20 parts of curing agent

[0015] 1-3 parts of curing accelerator

[0016] 10-30 parts solvent

[0017] The epoxy resin is one or more of bisphenol A epoxy resin, bisphenol S epoxy resin, bisphenol F epoxy resin, biphenyl epoxy resin, naphthalene epoxy resin, glycidyl ester epoxy resin, glycidyl amine epoxy resin, and alicyclic epoxy resin;

[0018] The thermoplastic rubber is a combination of one or more of carboxyl-terminated nitrile rubber, butyl rubber, hydrogenated nitrile rubber, nitrile rubber, and hydroxyl-terminated nitrile rubber;

[0019] The curing agent is a combination of one or more of dicyandiamide, diaminodiphenylmethane, amino resin, and anhydride curing agents;

[0020] The curing accelerator is a combination of one or more of 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, and 2-ethyl-4-phenylimidazole;

[0021] The solvent is a combination of one or more of toluene, acetone, xylene, methyl isobutyl ketone, methyl butyl ketone, ethylene glycol monoethyl ether, and ethylene glycol monomethyl ether;

[0022] The preparation process of the modified thermally conductive filler is as follows:

[0023] Step 1:

[0024] Phosphorus oxychloride and pentaerythritol are added to anhydrous acetonitrile and stirred evenly. Under nitrogen protection, the temperature is raised to 50-60°C and stirred for 0.5-1h. After adding aluminum chloride, the temperature is further raised to 80-90°C and stirred for 1-2h. After distilling off the solvent, the mixture is washed and dried to obtain intermediate 1. The mass ratio of phosphorus oxychloride, pentaerythritol and aluminum chloride is: 3-5:1-2:0.03-0.1; the amount of anhydrous acetonitrile used is 300-500ml.

[0025] Step 2:

[0026] Add intermediate 1, triethylamine and toluene to a flask, and dropwise add a toluene solution of p-hydroxybenzaldehyde to the flask. The temperature during the dropwise addition process is controlled at -5°C to 0°C. After the dropwise addition is completed, the temperature is raised to 65-80°C and kept for reaction for 3-5 hours. After the reaction is completed, the mixture is cooled, filtered, and the filtrate is vacuum-distilled to remove toluene and triethylamine to obtain intermediate 2. The molar ratio of intermediate 1, triethylamine and p-hydroxybenzaldehyde is 1:0.2:2.

[0027] Step 3:

[0028] Place the intermediate 2 and anhydrous methanol in a flask, and add dropwise a solution of 3-aminopropyltrimethoxysilane in anhydrous methanol while stirring under nitrogen protection. After the addition is completed, stir and react at 60-70°C for 5-8 hours. After the reaction is completed, pour the reaction product into ice water, filter, and dry to obtain a modified silane compound;

[0029] The molar ratio of the intermediate 2 to the 3-aminopropyltrimethoxysilane is 1:2;

[0030] Step 4:

[0031] The mixture of aluminum oxide and silicon carbide is added to 200-300 ml of a 10 wt% sodium hydroxide aqueous solution, stirred in a water bath at 70-80° C. for a reaction of 3-5 hours. After the reaction is completed, the mixture is cooled to room temperature, filtered, washed with water, and dried at 60° C. for 10-12 hours to obtain a surface hydroxylated aluminum oxide and silicon carbide mixture 1.

[0032] The mass ratio of the aluminum oxide to silicon carbide is 2-3:1;

[0033] Step 5:

[0034] The modified silane compound and γ-glycidyloxypropyltrimethoxysilane are added to 300-500 ml of 90 wt% ethanol aqueous solution for hydrolysis to obtain a hydrolysis solution, and the surface hydroxylated aluminum oxide and silicon carbide mixture 1 is added to the above hydrolysis solution; the mixture is refluxed under stirring for 2-3 hours at a reaction temperature of 60-70°C, and filtered, washed, and dried to obtain a modified thermal conductive filler.

[0035] The mass ratio of the modified silane compound, γ-glycidyloxypropyltrimethoxysilane, surface hydroxylated aluminum oxide and silicon carbide mixture 1 is 4-5:1-2:20-30.

[0036] The preparation method of the high thermal conductive epoxy resin composition comprises the following steps:

[0037] According to the formula, epoxy resin and thermoplastic rubber are weighed and added to the solvent, stirred evenly, and the modified thermal conductive filler is slowly added while stirring, and dispersed evenly using a high-speed shearing machine. Then, the curing agent and curing accelerator are added in sequence and stirred evenly to obtain a high thermal conductive epoxy resin composition.

[0038] The preparation method of the aluminum-based copper-clad laminate comprises the following steps:

[0039] Step 1: Apply the high thermal conductivity epoxy resin composition to the rough surface of the copper foil.

[0040] Step 2: baking the copper foil coated with the high thermal conductivity epoxy resin composition to form a semi-solid coated copper foil;

[0041] Step 3: Lay the semi-solidified adhesive-coated copper foil on the aluminum substrate, heat and pressurize to form the aluminum-based copper clad laminate, wherein the heating temperature is 160°C-210°C and the pressurizing pressure is 25-40kg / cm 2 , hot pressing time is 60-120min.

[0042] Compared with the prior art, the present invention has the following beneficial effects:

[0043] The present invention first uses phosphorus oxychloride and pentaerythritol in the presence of a catalyst to prepare a spirocyclic chlorinated bisphosphate, which is then reacted with p-hydroxybenzaldehyde to introduce aldehyde groups at both ends of the spirocyclic chlorinated bisphosphate to obtain an intermediate II. The intermediate II is then reacted with 3-aminopropyltrimethoxysilane to obtain a modified silane compound. The modified silane compound has a flame-retardant structure of the spirocyclic chlorinated bisphosphate, which can improve the flame retardancy of the system. The modified silane compound is used to modify a mixture of aluminum oxide and silicon carbide to obtain a modified filler, which can improve the dispersibility of the filler in the resin system. Furthermore, the γ-glycidyloxypropyltrimethoxysilane added during the filler modification process can introduce epoxy groups into the modified filler. During the curing process of the epoxy resin system, the epoxy groups introduced by the modified filler participate in the curing and cross-linking reaction, which can further improve the mechanical properties of the cured epoxy resin composition. DETAILED DESCRIPTION

[0044] The technical scheme of the present invention will be clearly and completely described below in conjunction with specific embodiments, but it will be understood by those skilled in the art that the following described embodiments are part of embodiments of the present invention, rather than all embodiments, and are only used to illustrate the present invention, and should not be considered as limiting the scope of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work premise belong to the scope of protection of the present invention. Those who do not specify specific conditions in the embodiments are carried out according to normal conditions or the conditions recommended by the manufacturer. Those whose reagents or instruments are not specified by the manufacturer are conventional products that can be purchased commercially.

[0045] Preparation Example 1

[0046] The preparation process of the modified thermally conductive filler is as follows:

[0047] Step 1:

[0048] 30.6 g of phosphorus oxychloride and 13.6 g of pentaerythritol were added to 400 ml of anhydrous acetonitrile and stirred evenly. Under nitrogen protection, the temperature was raised to 60°C and stirred for 1 hour. After adding 0.5 g of anhydrous aluminum chloride, the temperature was further raised to 80°C and stirred for 2 hours. After distilling off the solvent, the mixture was washed and dried to obtain intermediate 1.

[0049] Step 2:

[0050] 0.1 mol of intermediate 1, 0.2 mol of triethylamine and 450 ml of toluene were added to a flask, and 50 ml of a toluene solution containing 0.2 mol of p-hydroxybenzaldehyde was added dropwise to the flask. The temperature was controlled at -5°C during the addition process. After the addition was completed, the temperature was raised to 70°C and kept for reaction for 3 hours. After the reaction was completed, the mixture was cooled, filtered, and the filtrate was distilled under reduced pressure to remove toluene and triethylamine to obtain intermediate 2.

[0051] Step 3:

[0052] 0.1 mol of intermediate 2 and 400 ml of anhydrous methanol were added to a flask. 50 ml of anhydrous methanol solution of 0.2 mol of 3-aminopropyltrimethoxysilane was added dropwise while stirring under nitrogen protection. After the addition was completed, the mixture was stirred at 70°C for 6 hours. After the reaction was completed, the reaction product was poured into ice water, filtered, and dried to obtain a modified silane compound.

[0053] Step 4:

[0054] 20 g of aluminum oxide and 10 g of silicon carbide were added to 300 ml of a 10 wt% sodium hydroxide aqueous solution, and the mixture was stirred in a water bath at 70° C. for 3 h. After the reaction, the mixture was cooled to room temperature, filtered, washed with water, and dried at 60° C. for 12 h to obtain a surface hydroxylated aluminum oxide and silicon carbide mixture 1.

[0055] Step 5:

[0056] 5 g of a modified silane compound and 2 g of γ-glycidyloxypropyltrimethoxysilane were added to 300 ml of a 90 wt % ethanol aqueous solution for hydrolysis to obtain a hydrolysis solution. 30 g of a surface hydroxylated aluminum oxide and silicon carbide mixture 1 was added to the hydrolysis solution. The mixture was refluxed under stirring for 3 h at a reaction temperature of 70° C., and filtered, washed, and dried to obtain a modified thermally conductive filler 1.

[0057] Preparation Example 2

[0058] The preparation process of the modified thermally conductive filler is as follows:

[0059] Step 1:

[0060] 30.6 g of phosphorus oxychloride and 13.6 g of pentaerythritol were added to 400 ml of anhydrous acetonitrile and stirred evenly. Under nitrogen protection, the temperature was raised to 60°C and stirred for 1 hour. After adding 0.5 g of aluminum chloride, the temperature was further raised to 80°C and stirred for 2 hours. After distilling off the solvent, the mixture was washed and dried to obtain intermediate 1.

[0061] Step 2:

[0062] 0.1 mol of intermediate 1, 0.2 mol of triethylamine and 450 ml of toluene were added to a flask, and 50 ml of a toluene solution containing 0.2 mol of p-hydroxybenzaldehyde was added dropwise to the flask. The temperature was controlled at -5°C during the addition process. After the addition was completed, the temperature was raised to 70°C and kept for reaction for 3 hours. After the reaction was completed, the mixture was cooled, filtered, and the filtrate was distilled under reduced pressure to remove toluene and triethylamine to obtain intermediate 2.

[0063] Step 3:

[0064] 0.1 mol of intermediate 2 and 400 ml of anhydrous methanol were added to a flask. 50 ml of anhydrous methanol solution of 0.2 mol of 3-aminopropyltrimethoxysilane was added dropwise while stirring under nitrogen protection. After the addition was completed, the mixture was stirred at 70°C for 6 hours. After the reaction was completed, the reaction product was poured into ice water, filtered, and dried to obtain a modified silane compound.

[0065] Step 4:

[0066] 20 g of aluminum oxide and 10 g of silicon carbide were added to 300 ml of a 10 wt% sodium hydroxide aqueous solution, and the mixture was stirred in a water bath at 70° C. for 3 h. After the reaction, the mixture was cooled to room temperature, filtered, washed with water, and dried at 60° C. for 12 h to obtain a surface hydroxylated aluminum oxide and silicon carbide mixture 1.

[0067] Step 5:

[0068] 7 g of the modified silane compound was added to 300 ml of a 90 wt % ethanol aqueous solution for hydrolysis to obtain a hydrolysis solution. 30 g of a surface hydroxylated aluminum oxide and silicon carbide mixture 1 was added to the hydrolysis solution. The mixture was refluxed under stirring for 3 h at a reaction temperature of 70° C., and filtered, washed, and dried to obtain a modified thermally conductive filler 1.

[0069] Preparation Example 3

[0070] The preparation process of the modified thermally conductive filler is as follows:

[0071] 7 g of γ-glycidyloxypropyltrimethoxysilane was added to 300 ml of 90 wt % ethanol aqueous solution for hydrolysis to obtain a hydrolysis solution. 30 g of a surface hydroxylated aluminum oxide and silicon carbide mixture 1 was added to the hydrolysis solution. The mixture was refluxed under stirring for 3 h at a reaction temperature of 70° C., and filtered, washed, and dried to obtain a modified thermally conductive filler 1.

[0072] Example 1

[0073] Preparation of high thermal conductivity epoxy resin composition for aluminum-based copper-clad laminates:

[0074] According to the formula, 100 parts of epoxy resin E51 and 10 parts of terminal carboxyl nitrile rubber were weighed and added to 20 parts of toluene, and stirred evenly. 120 parts of the modified thermal conductive filler 1 obtained in Preparation Example 1 were slowly added while stirring, and dispersed evenly using a high-speed shearing machine at a speed of 1200 r / min and a dispersion time of 30 min. Then, 15 parts of dicyandiamide and 2 parts of 2-methylimidazole were added in sequence and stirred evenly to obtain a high thermal conductive epoxy resin composition.

[0075] Example 2

[0076] Preparation of high thermal conductivity epoxy resin composition for aluminum-based copper-clad laminates:

[0077] According to the formula, 100 parts of epoxy resin E51 and 15 parts of terminal hydroxyl nitrile rubber were weighed and added to 30 parts of toluene, and stirred evenly. 140 parts of the modified thermal conductive filler 1 obtained in Preparation Example 1 were slowly added while stirring, and dispersed evenly using a high-speed shearing machine with a speed of 1000 r / min and a dispersion time of 30 min. Then, 15 parts of diaminodiphenylmethane and 1.5 parts of 2-ethylimidazole were added in sequence and stirred evenly to obtain a high thermal conductive epoxy resin composition.

[0078] Example 3

[0079] Preparation of high thermal conductivity epoxy resin composition for aluminum-based copper-clad laminates:

[0080] According to the formula, 100 parts of bisphenol F epoxy resin and 18 parts of hydrogenated nitrile rubber were weighed and added to 30 parts of xylene, and stirred evenly. 160 parts of the modified thermal conductive filler 1 obtained in Preparation Example 1 were slowly added while stirring, and dispersed evenly using a high-speed shearing machine at a speed of 1500 r / min and a dispersion time of 30 min. Then, 12 parts of dicyandiamide and 3 parts of 2-phenylimidazole were added in sequence and stirred evenly to obtain a high thermal conductive epoxy resin composition.

[0081] Comparative Example 1

[0082] Preparation of high thermal conductivity epoxy resin composition for aluminum-based copper-clad laminates:

[0083] According to the formula, 100 parts of epoxy resin E51 and 10 parts of terminal carboxyl nitrile rubber were weighed and added to 20 parts of toluene, and stirred evenly. 120 parts of modified thermal conductive filler 2 obtained in Preparation Example 2 were slowly added while stirring, and dispersed evenly using a high-speed shearing machine with a speed of 1200 r / min and a dispersion time of 30 min. Then, 15 parts of dicyandiamide and 2 parts of 2-methylimidazole were added in sequence and stirred evenly to obtain a high thermal conductive epoxy resin composition.

[0084] Comparative Example 2

[0085] Preparation of high thermal conductivity epoxy resin composition for aluminum-based copper-clad laminates:

[0086] According to the formula, 100 parts of epoxy resin E51 and 10 parts of terminal carboxyl nitrile rubber were weighed and added to 20 parts of toluene, and stirred evenly. 120 parts of modified thermal conductive filler 3 obtained in Preparation Example 3 were slowly added while stirring, and dispersed evenly using a high-speed shearing machine with a speed of 1200 r / min and a dispersion time of 30 min. Then, 15 parts of dicyandiamide and 2 parts of 2-methylimidazole were added in sequence and stirred evenly to obtain a high thermal conductive epoxy resin composition.

[0087] Comparative Example 3

[0088] Preparation of high thermal conductivity epoxy resin composition for aluminum-based copper-clad laminates:

[0089] According to the formula, 100 parts of epoxy resin E51 and 10 parts of terminal carboxyl nitrile rubber were weighed and added to 20 parts of toluene, and stirred evenly. 80 parts of aluminum oxide and 40 parts of silicon carbide were slowly added while stirring. A high-speed shearing machine was used to disperse the mixture evenly at a speed of 1200 r / min and a dispersion time of 30 min. Then, 15 parts of dicyandiamide and 2 parts of 2-methylimidazole were added in sequence and stirred evenly to obtain a high thermal conductivity epoxy resin composition.

[0090] Application Examples

[0091] Aluminum-based copper-clad laminates were prepared using the high thermal conductivity epoxy resin compositions obtained in Examples 1 to 3 and Comparative Examples 1 to 3:

[0092] The preparation method of the aluminum-based copper-clad laminate comprises the following steps:

[0093] Step 1: Apply the high thermal conductivity epoxy resin composition to the rough surface of the copper foil.

[0094] Step 2: baking the copper foil coated with the high thermal conductivity epoxy resin composition to form a semi-solid coated copper foil;

[0095] Step 3: Lay the semi-solidified adhesive-coated copper foil on the aluminum substrate, heat and press to form the aluminum-based copper clad laminate, wherein the hot pressing temperature is 180°C and the pressure is 35kg / cm 2, hot pressing time is 100min, and the thickness of thermal conductive insulation layer is 100 microns.

[0096] Performance Testing

[0097] The thermally conductive insulating layers prepared in Examples 1 to 3 and Comparative Examples 1 to 3 of the present invention were tested and compared in terms of performance. The tensile strength of the thermally conductive insulating layers was tested according to GB1042-1979, and the thermal conductivity of the thermally conductive insulating layers was tested according to ASTM D5470-2006.

[0098] The results are shown in Table 1.

[0099] Table 1 Performance comparison of different thermal insulation layers

[0100]

[0101] From the experimental results in Table 1, it can be seen that the epoxy resin composition of the present invention has high thermal conductivity, tensile strength and flame retardancy. The modified filler of the present application has a certain degree of improvement in thermal conductivity, tensile strength and flame retardancy compared to the unmodified filler and the filler modified with γ-glycidyloxypropyltrimethoxysilane alone.

[0102] The performance of the aluminum-based copper-clad laminates prepared in Examples 1 to 3 of the present invention and Comparative Examples 1 to 3 was tested and compared. The performance testing methods are as follows:

[0103] (1) Peel strength of bending surface: The copper foil is etched into a circuit with a width of 3 mm, and the circuit is fixed after being bent using a bending mold. The adhesion between the copper foil and the insulation layer is tested using a peel strength tester. The test conditions are: 288°C after thermal stress, 10s.

[0104] (2) Thermal stress: Cut the sample to be tested into three 50×50 mm samples. After bending them with a bending mold, immerse the 50×50 mm sample in a tin furnace at 288°C and observe the time for the sample to delaminate and bubble. The longer the time, the better the heat resistance.

[0105] (3) Baking plate: Cut the sample to be tested into three pieces of 100×100 mm and bake them in an oven at 288°C for 2 h. Observe the stratification and bubbling of the samples.

[0106] (4) Breakdown voltage: According to the IEC60243-1 method, the breakdown voltage of the thermal insulation layer is tested and the average value of 5 points is taken.

[0107] The results are shown in Table 2.

[0108] Table 2 Performance comparison of different aluminum-based copper clad laminates

[0109]

[0110] The experimental results in Table 2 show that the aluminum-based copper-clad laminate prepared using the epoxy resin composition of the present application exhibits excellent flexural peel strength, heat resistance, and breakdown voltage resistance. Furthermore, compared to unmodified fillers and fillers modified solely with γ-glycidoxypropyltrimethoxysilane, these fillers exhibit significant improvements in peelability, heat resistance, and breakdown voltage resistance.

[0111] The above contents are merely examples and explanations of the concept of the present invention. Those skilled in the art may make various modifications or additions to the described specific embodiments or replace them in a similar manner. As long as they do not deviate from the concept of the invention or exceed the defined scope, they should all fall within the scope of protection of the present invention.

Claims

1. A high thermal conductivity epoxy resin composition for copper clad laminates, characterized in that: The preparation method is based on the following components: 100 parts epoxy resin 10-20 parts of thermoplastic rubber 120-160 parts of modified thermal conductive filler 5-20 parts of curing agent 1-3 parts of curing accelerator 10-30 parts of solvent; The preparation process of the modified thermally conductive filler is as follows: Step 1: Phosphorus oxychloride and pentaerythritol are added to anhydrous acetonitrile and stirred evenly. Under nitrogen protection, the temperature is raised to 50-60°C and stirred for 0.5-1h. Anhydrous aluminum chloride is added and the temperature is further raised to 80-90°C and stirred for 1-2h. The solvent is removed by distillation, and the mixture is washed and dried to obtain intermediate 1. The mass ratio of phosphorus oxychloride, pentaerythritol, and anhydrous aluminum chloride is: 3-5:1-2:0.03-0.1; the amount of anhydrous acetonitrile used is 300-500ml. Step 2: Add intermediate 1, triethylamine and toluene to a flask, and dropwise add a toluene solution of p-hydroxybenzaldehyde to the flask. The temperature during the dropwise addition process is controlled at -5°C to 0°C. After the dropwise addition is completed, the temperature is raised to 65-80°C and kept for reaction for 3-5 hours. After the reaction is completed, the mixture is cooled, filtered, and the filtrate is decompressed and distilled to remove toluene and triethylamine to obtain intermediate 2. The molar ratio of intermediate 1, triethylamine and p-hydroxybenzaldehyde is 1:0.2:

2. Step 3: The intermediate 2 and anhydrous methanol were placed in a flask, and an anhydrous methanol solution of 3-aminopropyltrimethoxysilane was added dropwise while stirring under nitrogen protection. After the addition was completed, the mixture was stirred at 60-70°C for 5-8 hours. After the reaction was completed, the reaction product was poured into ice water, filtered, and dried to obtain a modified silane compound; the molar ratio of the intermediate 2 to the 3-aminopropyltrimethoxysilane was 1:2; Step 4: The mixture of aluminum oxide and silicon carbide is added to 200-300 ml of a 10 wt% sodium hydroxide aqueous solution, stirred in a water bath at 70-80° C. for a reaction of 3-5 hours. After the reaction is completed, the mixture is cooled to room temperature, filtered, washed with water, and dried at 60° C. for 10-12 hours to obtain a surface hydroxylated aluminum oxide and silicon carbide mixture 1; the mass ratio of the aluminum oxide to the silicon carbide is 2-3:1; Step 5: The modified silane compound and γ-glycidyloxypropyltrimethoxysilane are added to 300-500 ml of a 90 wt% ethanol aqueous solution for hydrolysis to obtain a hydrolysis solution, and the surface hydroxylated aluminum oxide and silicon carbide mixture 1 is added to the hydrolysis solution; Reflux reaction under stirring conditions for 2 to 3 hours at a reaction temperature of 60-70°C, filtering, washing, and drying to obtain a modified thermal conductive filler; The mass ratio of the modified silane compound, γ-glycidyloxypropyltrimethoxysilane, surface hydroxylated aluminum oxide and silicon carbide mixture 1 is 4-5:1-2:20-30.

2. The high thermal conductivity epoxy resin composition for copper clad laminate according to claim 1, wherein: The epoxy resin is one or a combination of bisphenol A epoxy resin, bisphenol S epoxy resin, bisphenol F epoxy resin, biphenyl epoxy resin, naphthalene epoxy resin, glycidyl ester epoxy resin, glycidyl amine epoxy resin, and alicyclic epoxy resin.

3. The high thermal conductivity epoxy resin composition for copper clad laminate according to claim 1, wherein: The thermoplastic rubber is a combination of one or more of carboxyl-terminated nitrile rubber, butyl rubber, hydrogenated nitrile rubber, nitrile rubber, and hydroxyl-terminated nitrile rubber.

4. The high thermal conductivity epoxy resin composition for copper clad laminate according to claim 1, wherein: The curing agent is a combination of one or more of dicyandiamide, diaminodiphenylmethane, amino resin, and acid anhydride curing agents.

5. The high thermal conductivity epoxy resin composition for copper clad laminate according to claim 1, wherein: The curing accelerator is a combination of one or more of 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, and 2-ethyl-4-phenylimidazole.

6. The high thermal conductivity epoxy resin composition for copper clad laminate according to claim 1, wherein: The solvent is a combination of one or more of toluene, acetone, xylene, methyl isobutyl ketone, methyl butyl ketone, ethylene glycol monoethyl ether, and ethylene glycol monomethyl ether.

7. The method for preparing a high thermal conductivity epoxy resin composition for copper clad laminates according to any one of claims 1 to 6, wherein: The method comprises the following steps: weighing epoxy resin and thermoplastic rubber according to the formula, adding them to a solvent, stirring evenly, slowly adding a modified thermal conductive filler while stirring, dispersing evenly using a high-speed shearing machine, and then sequentially adding a curing agent and a curing accelerator, and stirring evenly to obtain a high thermal conductive epoxy resin composition.

8. A method for preparing an aluminum-based copper-clad laminate, characterized in that: The steps include: Step 1: applying the high thermal conductivity epoxy resin composition according to any one of claims 1 to 6 to the rough surface of the copper foil; Step 2: baking the copper foil coated with the high thermal conductivity epoxy resin composition to form a semi-solid coated copper foil; Step 3: Laminating the semi-solid glue-coated copper foil with the aluminum substrate, heating and pressurizing to form the aluminum-based copper clad laminate.

9. The method for preparing an aluminum-based copper-clad laminate according to claim 8, wherein: In step 3, the heating temperature is 160-210°C and the pressurization pressure is 25-40 kg / cm 2 , hot pressing time is 60-120min.

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