A high thermal conductivity copper clad laminate and its preparation process

Abstract

The present invention discloses a high thermal conductivity copper clad laminate and a preparation process thereof, comprising the following steps: (1) pretreatment of inorganic particles; (2) modification of inorganic particles; (3) preparation of adhesive solution; (4) preparation of high thermal conductivity adhesive solution; (5) preparation of copper clad laminate. The high thermal conductivity copper clad laminate provided by the present invention is prepared by mixing inorganic particle powder, polyetheretherketone powder, epoxy resin and polyphenylene ether powder to obtain a high thermal conductivity adhesive solution, which is then used as an impregnation resin for the copper clad laminate, and then heated and cured, so that the prepared copper clad laminate has excellent thermal conductivity and heat resistance, high peel strength and mechanical strength, and low water absorption, and has good application prospects.

Description

Technical Field

[0001] The invention belongs to the technical field of copper clad laminates, and in particular relates to a high thermal conductivity copper clad laminate and a preparation process thereof. Background Art

[0002] Copper clad laminate (abbreviated as copper clad laminate) is a plate-shaped material made by impregnating the reinforcing material with resin, covering one or both sides with copper foil, and then hot pressing. Copper clad laminate is the base material for processing printed circuit boards (PCBs), and its development is largely dependent on the development of the PCB industry. PCB has now become an indispensable main component for the interconnection of circuits in most electronic products. With the invention and application of integrated circuits, the miniaturization and high performance of electronic products have promoted the development of copper clad laminate technology. High-end electronic products such as automotive electronics and IC packaging have put forward higher requirements on the reliability of PCB substrates. The reliability requirements are mainly based on the development trend of PCBs towards fine lines, small holes, thin plates, and laminates, as well as the implementation of the ROSH directive under the social environment of ROSH laws and electronic products towards high-frequency transmission. The biggest impact on PCBs is the lead-free process, which puts forward higher requirements on the reliability of PCB substrates.

[0003] In order to ensure the high reliability of electronic equipment, copper clad laminates must have the following properties: excellent heat resistance, that is, high glass transition temperature, thermal decomposition temperature and long thermal stratification time; high mechanical strength; low thermal expansion coefficient; excellent flame retardant properties; lower dielectric constant and dielectric loss to ensure high signal transmission rate and efficiency of PCB; excellent resistance to moisture and heat and high pressure cooking; good resistance to CAF (Conductive Anodic Filament, leakage phenomenon of anodic glass filament); good long-term heat aging resistance; and excellent processing performance.

[0004] Thermally conductive copper clad laminates are a new type of copper clad laminates with a certain thermal conductivity that are specially researched and developed to address the shortcomings of low thermal conductivity of ordinary copper clad laminates. Thermally conductive copper clad laminates developed on the basis of ordinary copper clad laminates can be roughly divided into two categories: thermally conductive metal-based and resin-based thermally conductive copper clad laminates. There is no obvious difference in structure from ordinary copper clad laminates, and their thermal conductivity is improved on the basis of retaining electrical insulation performance. Thermal conductivity is an important indicator of thermally conductive copper clad laminates. In the prior art, in order to improve the thermal conductivity of the thermally conductive insulating layer, the amount of thermally conductive particles is often increased, which will cause the viscosity of the glue to increase, processing difficulties, poor mechanical strength and toughness of the matrix, reduced bonding performance, and more gaps inside the system, reducing electrical breakdown and insulation performance. Therefore, increasing the amount of thermally conductive particles in order to unilaterally pursue high thermal conductivity will affect and destroy the balance between other physical performance indicators, and the prepared thermally conductive copper clad laminate has poor comprehensive performance.

[0005] Chinese patent application No. 201910077824.1 discloses a method for preparing a copper clad laminate with high thermal conductivity: 2-aminophenol, sodium hydroxide and ethanol are mixed to obtain solution A; formaldehyde solution is added to solution A, the pH is adjusted to neutral, and polyethylene glycol is added to obtain solution B; F127 is added to solution B, coated, dried, heated and kept warm, and then immersed in an ethanol solution of maleic acid and tetrahydropyrrole, washed and dried to obtain solid phase D; solid phase D is immersed in an ethanol solution of chloroiridic acid, tetraethyl orthosilicate and isopropanol, dried to obtain solid phase E; solid phase E is heated to obtain solid phase F; solid phase F is mixed with epoxy resin, carboxyl liquid nitrile rubber, dicyandiamide, 1-methylimidazole and acetone, coated and dried to obtain resin-coated copper foil and resin-coated aluminum substrate; the copper foil and the aluminum substrate are laminated and compacted, and vacuum pressed to obtain a copper clad laminate. However, the method for preparing copper clad laminates in this patent is relatively complicated, not conducive to industrial production, and does not mention how to improve the heat resistance of copper clad laminates. Summary of the invention

[0006] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a high thermal conductivity copper clad laminate and a preparation process thereof. The prepared copper clad laminate has a high thermal conductivity and heat resistance temperature, as well as high peel strength and mechanical strength; the operation process is simple, the preparation conditions are mild, the production cost is low, and it is easy to mass-produce and scale production, and has a good industrial production foundation and broad application prospects.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A preparation process of a high thermal conductivity copper clad laminate comprises the following steps:

[0009] (1) Pretreatment of inorganic particles: silicon carbide powder and aluminum nitride powder are added to a ball mill, followed by anhydrous ethanol, and wet ball milling is performed to obtain pretreated inorganic particles;

[0010] (2) Modification of inorganic particles: adding the pretreated inorganic particles obtained in step (1) to anhydrous ethanol, followed by adding tetrabutyl titanate, deionized water, and sodium dodecylbenzene sulfonate, stirring evenly, adding aqueous ammonia, and performing a hydrothermal reaction. After the reaction is completed, filtering, washing, and drying are performed, and then calcining under a nitrogen atmosphere to obtain modified inorganic particles;

[0011] (3) Preparation of glue solution: epoxy resin, polyphenylene ether powder, phthalic anhydride and dicyandiamide are uniformly mixed, and then acetone and triphenylphosphine are added to react with stirring at a constant temperature. After the reaction is completed, glue solution is obtained;

[0012] (4) Preparation of a highly thermally conductive adhesive: adding the modified inorganic particles, polyetheretherketone, and 3-chloropropyltrimethoxysilane in step (2) to a ball mill for ball milling to obtain mixed particles, and then adding the mixed particles to the adhesive in step (3), stirring at room temperature, and obtaining a highly thermally conductive adhesive after stirring;

[0013] (5) Preparation of copper clad laminate: The cut glass fiber cloth is evenly coated with the high thermal conductivity adhesive solution described in step (4), and baked in an oven to obtain a prepreg. The prepregs with a flat surface and uniform coating are cut according to size, stacked neatly, copper foils are attached to both sides, and pressed in a hot press to obtain the high thermal conductivity copper clad laminate.

[0014] Preferably, in step (1), the mass ratio of silicon carbide powder to aluminum nitride powder is 1-3:1; the ball milling speed is 1500-3000 r / min, and the time is 2-3 h.

[0015] Preferably, in step (2), the mass ratio of the pretreated inorganic particles, tetrabutyl titanate, deionized water, sodium dodecylbenzene sulfonate and ammonia water is 10:50-100:30-40:100-150:60-80; and the mass concentration of the ammonia water is 20-25%.

[0016] Preferably, the temperature of the hydrothermal reaction in step (2) is 120-160° C., and the reaction time is 5-10 h; the calcination temperature is 900-1100° C., and the calcination time is 2-4 h.

[0017] Preferably, in parts by weight, the raw materials in step (3) are 60-80 parts of epoxy resin, 10-15 parts of polyphenylene ether powder, 10-20 parts of phthalic anhydride, 10-20 parts of dicyandiamide, 20-40 parts of acetone, and 2-5 parts of triphenylphosphine.

[0018] Preferably, the constant temperature stirring in step (3) is 50-70°C, the time is 1-2h, and the stirring speed is 200-300r / min.

[0019] Preferably, in step (4), the mass ratio of the modified inorganic particles, polyetheretherketone, and 3-chloropropyltrimethoxysilane is 100:10-15:1-5; the ball milling speed is 2500-3500 r / min, and the time is 0.5-1 h.

[0020] Preferably, in step (4), the mass ratio of the mixed particles to the glue is 5-10:100; the stirring speed is 300-500 r / min, and the time is 0.5-1 h.

[0021] Preferably, the baking temperature in step (5) is 60-80°C and the time is 20-40 min; the pressing conditions are: temperature 180-240°C, pressure 1-3 MPa, and curing time 80-120 min.

[0022] The present invention also protects a high thermal conductivity copper clad plate prepared by the preparation process.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] (1) The high thermal conductivity copper clad laminate preparation process provided by the present invention comprises mixing epoxy resin and polyphenylene ether powder, introducing phthalic anhydride as a compatibilizer, and making the two less likely to phase separate during heating and curing. At the same time, the added phthalic anhydride has a benzene ring group, which can improve the rigidity of the epoxy resin and improve the heat resistance. Subsequently, the imidazole curing agent dicyandiamide is added. During heating and curing, the polyphenylene ether powder is melted and forms a semi-interpenetrating polymer network with other components in the epoxy resin, which can increase the crosslinking density and mechanical properties of the epoxy resin after curing. When the epoxy resin is heated, its internal steric hindrance increases, so that the activity of its chain segments is restricted, thereby improving the heat resistance of the epoxy resin.

[0025] (2) The high thermal conductivity copper-clad laminate preparation process provided by the present invention improves the surface energy of the powder particles by mixing and wet-grinding the silicon carbide powder and the aluminum nitride powder, so that the powder particles can be better mixed and evenly mixed, and the wettability of the powder particles in the solution is also improved, which is beneficial to the subsequent coating reaction; then the pretreated inorganic particles are hydrothermally reacted with tetrabutyl titanate to generate nano-titanium dioxide particles in situ on the surface of the inorganic particles, which can form irregular particles and increase the contact area of ​​the particles, thereby making the heat transfer effect better. In addition, the particle sizes of the nano-titanium dioxide, the silicon carbide powder and the aluminum nitride powder are different, and a size effect can be generated between the particles. The compound filling of the inorganic mixed particles makes the particles stack more densely, and the construction More heat-conducting network chains can be produced, thereby enhancing the thermal conductivity of the copper clad laminate; then the modified inorganic particles are blended with polyetheretherketone and 3-chloropropyltrimethoxysilane for ball milling. 3-Chloropropyltrimethoxysilane can effectively improve the dispersibility of inorganic particles and polyetheretherketone in the adhesive, and also improve the compatibility of inorganic particles with the adhesive, thereby improving the mechanical properties of the copper clad laminate. Polyetheretherketone powder is added to the system as a filler. Its excellent heat resistance and insulation properties can improve the heat resistance of epoxy resin together with the modified inorganic particles, thereby avoiding the disadvantage of being unable to be evenly dispersed in the resin due to the difficulty in processing polyetheretherketone. At the same time, polyetheretherketone also has good water absorption resistance and can effectively extend the service life of the copper clad laminate.

[0026] (3) The high thermal conductivity copper clad laminate provided by the present invention is prepared by mixing inorganic particle powder, polyetheretherketone powder, epoxy resin and polyphenylene ether powder to obtain a high thermal conductivity adhesive liquid, which is then used as an impregnation resin for the copper clad laminate, and then heated and cured. The prepared copper clad laminate has excellent thermal conductivity and heat resistance, high peel strength and mechanical strength, and low water absorption, and has good application prospects. DETAILED DESCRIPTION

[0027] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] The epoxy resin was purchased from Jining Sanshi Biotechnology Co., Ltd., model E51; the polyphenylene ether powder was purchased from Dongguan Xingxiang New Materials Co., Ltd., with a mesh size of 200 mesh; the polyetheretherketone powder was purchased from Ningbo Dinghang Special Plastic Co., Ltd., with a mesh size of 325 mesh; the particle size of the silicon carbide powder was 600-800 mesh, and the particle size of the aluminum nitride was 400-600 mesh.

[0029] Example 1

[0030] A preparation process of a high thermal conductivity copper clad laminate comprises the following steps:

[0031] (1) Pretreatment of inorganic particles: 200 g of silicon carbide powder and 100 g of aluminum nitride powder were added to a ball mill, followed by 80 mL of anhydrous ethanol, and wet ball milling was performed at a speed of 2500 r / min for 2.5 h. After the ball milling was completed, pretreated inorganic particles were obtained;

[0032] (2) Modification of inorganic particles: The pretreated inorganic particles (100 g) obtained in step (1) were added to 700 mL of anhydrous ethanol, followed by the addition of 370 g of tetrabutyl titanate, 700 g of deionized water, and 17 g of sodium dodecylbenzene sulfonate. After stirring, 350 g of 23% ammonia water was added. The mixture was hydrothermally reacted at 140° C. for 8 h. After the reaction was completed, the mixture was filtered, washed, and dried. The mixture was then calcined in a nitrogen atmosphere at a temperature of 1000° C. for 3 h to obtain modified inorganic particles.

[0033] (3) Preparation of glue solution: 700 g of epoxy resin, 130 g of polyphenylene ether powder, 170 g of phthalic anhydride, and 170 g of dicyandiamide were mixed evenly, and then 300 g of acetone and 40 g of triphenylphosphine were added. The mixture was stirred at a constant temperature of 60° C. for 1.5 h at a stirring speed of 250 r / min. After the reaction was completed, a glue solution was obtained;

[0034] (4) Preparation of high thermal conductive adhesive: Add the modified inorganic particles (100 g) in step (2), 13 g of polyetheretherketone, and 4 g of 3-chloropropyltrimethoxysilane into a ball mill and perform ball milling at a speed of 3000 r / min for 1 h to obtain mixed particles. Then, add 80 g of the mixed particles into the adhesive (1000 g) in step (3) and stir at room temperature at a speed of 400 r / min for 1 h. After stirring, a high thermal conductive adhesive is obtained.

[0035] (5) Preparing a copper clad laminate: evenly coating the cut glass fiber cloth with the high thermal conductivity adhesive solution described in step (4), and baking in an oven to obtain a prepreg, the baking temperature is 70° C., and the baking time is 30 min; cutting the prepregs with a flat surface and uniform coating according to the size, stacking them neatly, attaching copper foil on both sides, and placing them in a hot press to press, the pressing conditions are: temperature is 220° C., pressure is 2 MPa, and curing time is 100 min, to obtain the high thermal conductivity copper clad laminate.

[0036] Example 2

[0037] A preparation process of a high thermal conductivity copper clad laminate comprises the following steps:

[0038] (1) Pretreatment of inorganic particles: 200 g of silicon carbide powder and 100 g of aluminum nitride powder were added to a ball mill, followed by 70 mL of anhydrous ethanol, and wet ball milling was performed at a speed of 2000 r / min for 2.5 h. After the ball milling was completed, pretreated inorganic particles were obtained;

[0039] (2) Modification of inorganic particles: The pretreated inorganic particles (100 g) obtained in step (1) were added to 600 mL of anhydrous ethanol, followed by the addition of 330 g of tetrabutyl titanate, 600 g of deionized water, and 13 g of sodium dodecylbenzene sulfonate. After stirring, 300 g of 22% ammonia water was added. The mixture was hydrothermally reacted at 140° C. for 7 h. After the reaction was completed, the mixture was filtered, washed, and dried. The mixture was then calcined in a nitrogen atmosphere at a temperature of 1000° C. for 3 h to obtain modified inorganic particles.

[0040] (3) Preparation of glue solution: 700 g of epoxy resin, 120 g of polyphenylene ether powder, 130 g of phthalic anhydride, and 130 g of dicyandiamide were mixed evenly, and then 300 g of acetone and 30 g of triphenylphosphine were added. The mixture was stirred at a constant temperature of 60° C. for 1.5 h at a stirring speed of 250 r / min. After the reaction was completed, a glue solution was obtained;

[0041] (4) Preparation of high thermal conductive adhesive: Add the modified inorganic particles (100 g) in step (2), 12 g of polyetheretherketone, and 3 g of 3-chloropropyltrimethoxysilane into a ball mill and perform ball milling at a speed of 2000 r / min for 0.5 h to obtain mixed particles. Then, add 70 g of the mixed particles into the adhesive (1000 g) in step (3) and stir at room temperature at a speed of 400 r / min for 1 h. After stirring, a high thermal conductive adhesive is obtained.

[0042] (5) Preparing a copper clad laminate: evenly coating the cut glass fiber cloth with the high thermal conductivity adhesive solution described in step (4), and baking in an oven to obtain a prepreg, the baking temperature is 70° C., and the baking time is 30 min; cutting the prepregs with flat surfaces and even coating according to the size, stacking them neatly, attaching copper foil on both sides, and pressing them in a hot press, the pressing conditions are: temperature is 200° C., pressure is 2 MPa, and curing time is 100 min, to obtain the high thermal conductivity copper clad laminate.

[0043] Example 3

[0044] A preparation process of a high thermal conductivity copper clad laminate comprises the following steps:

[0045] (1) Pretreatment of inorganic particles: 100 g of silicon carbide powder and 100 g of aluminum nitride powder were added to a ball mill, followed by 50 mL of anhydrous ethanol, and wet ball milling was performed at a speed of 1500 r / min for 3 h. After the ball milling was completed, pretreated inorganic particles were obtained;

[0046] (2) Modification of inorganic particles: The pretreated inorganic particles (100 g) obtained in step (1) were added to 500 mL of anhydrous ethanol, followed by the addition of 300 g of tetrabutyl titanate, 500 g of deionized water, and 10 g of sodium dodecylbenzene sulfonate. After stirring, 200 g of 20% ammonia water was added. The mixture was hydrothermally reacted at 120° C. for 10 h. After the reaction was completed, the mixture was filtered, washed, and dried. The mixture was then calcined in a nitrogen atmosphere at a temperature of 900° C. for 4 h to obtain modified inorganic particles.

[0047] (3) Preparation of glue solution: 600 g of epoxy resin, 100 g of polyphenylene ether powder, 100 g of phthalic anhydride, and 100 g of dicyandiamide were mixed uniformly, and then 200 g of acetone and 20 g of triphenylphosphine were added. The mixture was stirred at a constant temperature of 50° C. for 2 h at a stirring speed of 200 r / min. After the reaction was completed, a glue solution was obtained;

[0048] (4) Preparation of high thermal conductive adhesive: Add the modified inorganic particles (100 g) in step (2), 10 g of polyetheretherketone, and 1 g of 3-chloropropyltrimethoxysilane into a ball mill and mill them at a speed of 2500 r / min for 1 h to obtain mixed particles. Then, add 50 g of the mixed particles into the adhesive (1000 g) in step (3) and stir at room temperature at a speed of 300 r / min for 1 h. After stirring, a high thermal conductive adhesive is obtained.

[0049] (5) Preparing a copper clad laminate: evenly coating the cut glass fiber cloth with the high thermal conductivity adhesive solution described in step (4), and baking in an oven to obtain a prepreg, the baking temperature is 60° C., and the baking time is 40 min; cutting the prepregs with a flat surface and uniform coating according to the size, stacking them neatly, attaching copper foil on both sides, and pressing them in a hot press, the pressing conditions are: temperature is 180° C., pressure is 1 MPa, and curing time is 120 min, to obtain the high thermal conductivity copper clad laminate.

[0050] Example 4

[0051] A preparation process of a high thermal conductivity copper clad laminate comprises the following steps:

[0052] (1) Pretreatment of inorganic particles: 300 g of silicon carbide powder and 100 g of aluminum nitride powder were added to a ball mill, followed by 100 mL of anhydrous ethanol, and wet ball milling was performed at a speed of 3000 r / min for 2 h. After the ball milling was completed, pretreated inorganic particles were obtained;

[0053] (2) Modification of inorganic particles: The pretreated inorganic particles (100 g) obtained in step (1) were added to 800 mL of anhydrous ethanol, followed by the addition of 400 g of tetrabutyl titanate, 800 g of deionized water, and 20 g of sodium dodecylbenzene sulfonate. After stirring, 400 g of 25% ammonia water was added. The mixture was hydrothermally reacted at 160° C. for 5 h. After the reaction was completed, the mixture was filtered, washed, and dried. The mixture was then calcined in a nitrogen atmosphere at a temperature of 1100° C. for 2 h to obtain modified inorganic particles.

[0054] (3) Preparation of glue solution: 800 g of epoxy resin, 150 g of polyphenylene ether powder, 200 g of phthalic anhydride, and 200 g of dicyandiamide were mixed uniformly, and then 400 g of acetone and 50 g of triphenylphosphine were added. The mixture was stirred at a constant temperature of 70° C. for 1 h at a stirring speed of 300 r / min. After the reaction was completed, a glue solution was obtained;

[0055] (4) Preparation of high thermal conductive adhesive: Add the modified inorganic particles (100 g) in step (2), 15 g of polyetheretherketone, and 5 g of 3-chloropropyltrimethoxysilane into a ball mill and perform ball milling at a speed of 3500 r / min for 0.5 h to obtain mixed particles. Then, add 100 g of the mixed particles into the adhesive (1000 g) in step (3) and stir at room temperature at a speed of 500 r / min for 0.5 h. After stirring, a high thermal conductive adhesive is obtained.

[0056] (5) Preparing a copper clad laminate: evenly coating the cut glass fiber cloth with the high thermal conductivity adhesive solution described in step (4), and baking in an oven to obtain a prepreg, the baking temperature is 80° C., and the baking time is 20 min; cutting the prepregs with a flat surface and uniform coating according to the size, stacking them neatly, attaching copper foil on both sides, and placing them in a hot press to press, the pressing conditions are: temperature is 240° C., pressure is 1 MPa, and curing time is 80 min, to obtain the high thermal conductivity copper clad laminate.

[0057] Comparative Example 1

[0058] A preparation process of a high thermal conductivity copper clad laminate comprises the following steps:

[0059] (1) Pretreatment of inorganic particles: 200 g of silicon carbide powder and 100 g of aluminum nitride powder were added to a ball mill, followed by 80 mL of anhydrous ethanol, and wet ball milling was performed at a speed of 2500 r / min for 2.5 h. After the ball milling was completed, pretreated inorganic particles were obtained;

[0060] (2) Preparation of glue solution: 700 g of epoxy resin, 130 g of polyphenylene ether powder, 170 g of phthalic anhydride, and 170 g of dicyandiamide were mixed evenly, and then 300 g of acetone and 40 g of triphenylphosphine were added. The mixture was stirred at a constant temperature of 60° C. for 1.5 h at a stirring speed of 250 r / min. After the reaction was completed, a glue solution was obtained;

[0061] (3) Preparation of high thermal conductive adhesive: The pretreated inorganic particles (100 g) in step (1), 13 g of polyetheretherketone, and 4 g of 3-chloropropyltrimethoxysilane were added to a ball mill for ball milling at a speed of 3000 r / min for 1 h to obtain mixed particles, and then 80 g of the mixed particles were added to the adhesive (1000 g) in step (2) and stirred at room temperature at a speed of 400 r / min for 1 h. After stirring, a high thermal conductive adhesive was obtained;

[0062] (4) Preparing a copper clad laminate: evenly coating the cut glass fiber cloth with the high thermal conductivity adhesive solution described in step (3), and baking in an oven to obtain a prepreg, the baking temperature is 70° C., and the baking time is 30 min; cutting the prepregs with a flat surface and uniform coating according to the size, stacking them neatly, attaching copper foil on both sides, and pressing them in a hot press, the pressing conditions are: temperature is 220° C., pressure is 2 MPa, and curing time is 100 min, to obtain the high thermal conductivity copper clad laminate.

[0063] Comparative Example 2

[0064] A preparation process of a high thermal conductivity copper clad laminate comprises the following steps:

[0065] (1) Pretreatment of inorganic particles: 200 g of silicon carbide powder and 100 g of aluminum nitride powder were added to a ball mill, followed by 80 mL of anhydrous ethanol, and wet ball milling was performed at a speed of 2500 r / min for 2.5 h. After the ball milling was completed, pretreated inorganic particles were obtained;

[0066] (2) Modification of inorganic particles: The pretreated inorganic particles (100 g) obtained in step (1) were added to 700 mL of anhydrous ethanol, followed by the addition of 370 g of tetrabutyl titanate, 700 g of deionized water, and 17 g of sodium dodecylbenzene sulfonate. After stirring, 350 g of 23% ammonia water was added. The mixture was hydrothermally reacted at 140° C. for 8 h. After the reaction was completed, the mixture was filtered, washed, and dried. The mixture was then calcined in a nitrogen atmosphere at a temperature of 1000° C. for 3 h to obtain modified inorganic particles.

[0067] (3) Preparation of glue solution: 700 g of epoxy resin, 170 g of phthalic anhydride and 170 g of dicyandiamide were mixed evenly, and then 300 g of acetone and 40 g of triphenylphosphine were added. The mixture was stirred at a constant temperature of 60° C. for 1.5 h at a stirring speed of 250 r / min. After the reaction was completed, a glue solution was obtained;

[0068] (4) Preparation of high thermal conductive adhesive solution: Add the modified inorganic particles (80 g) in step (2) to the adhesive solution (1000 g) in step (3), and stir at room temperature at a speed of 400 r / min for 1 h to obtain a high thermal conductive adhesive solution;

[0069] (5) Preparing a copper clad laminate: evenly coating the cut glass fiber cloth with the high thermal conductivity adhesive solution described in step (4), and baking in an oven to obtain a prepreg, the baking temperature is 70° C., and the baking time is 30 min; cutting the prepregs with a flat surface and uniform coating according to the size, stacking them neatly, attaching copper foil on both sides, and placing them in a hot press to press, the pressing conditions are: temperature is 220° C., pressure is 2 MPa, and curing time is 100 min, to obtain the high thermal conductivity copper clad laminate.

[0070] The high thermal conductivity copper clad laminates prepared in Examples 1-4 and Comparative Examples 1-2 were subjected to performance tests, wherein the thermal conductivity test method was carried out according to the ASTM-5470 method; the peel strength was tested according to GB / T 4722-2017; the bending strength was tested according to the standard GB / T 2567-2021, and the bending strength specimen size was 4.0 mm thick, 100 mm long, 15 mm wide, the test speed was 10 mm / min, the number of tests was 5, the test temperature was 23°C, the relative humidity was 50%, and the specimen conditioning time was 30 h; the test results are shown in Table 1 below:

[0071] Table 1

[0072] Thermal conductivity W / (mK) Breakdown voltage / kV Peel strength (N / mm) Bending strength(MPa) Example 1 2.61 7.43 2.27 224 Example 2 2.34 7.28 2.15 212 Example 3 2.48 6.97 2.09 199 Example 4 2.55 7.12 2.18 207 Comparative Example 1 1.52 4.51 1.62 185 Comparative Example 2 1.66 4.36 1.53 197

[0073] It can be seen from Table 1 above that the high thermal conductivity copper clad laminate prepared by the present invention has good thermal conductivity. At the same time, the added modified inorganic particles have no effect on its mechanical properties, and the copper clad laminate has good peel strength and breakdown voltage, and has good application prospects.

[0074] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A process for preparing a high thermal conductivity copper-clad laminate, characterized in that: The following steps are involved: (1) Pretreatment of inorganic particles: Add silicon carbide powder and aluminum nitride powder into a ball mill, then add anhydrous ethanol and perform wet ball milling. After the ball milling is completed, pretreated inorganic particles are obtained; (2) Modification of inorganic particles: the pretreated inorganic particles obtained in step (1) are added to anhydrous ethanol, followed by tetrabutyl titanate, deionized water, and sodium dodecylbenzene sulfonate. After stirring, ammonia water is added to carry out a hydrothermal reaction. After the reaction is completed, the particles are filtered, washed, and dried, and then calcined in a nitrogen atmosphere to obtain modified inorganic particles. (3) Preparation of glue solution: epoxy resin, polyphenylene ether powder, phthalic anhydride and dicyandiamide are mixed evenly, and then acetone and triphenylphosphine are added to react under constant temperature stirring. After the reaction is completed, glue solution is obtained; (4) Preparation of a highly thermally conductive adhesive: adding the modified inorganic particles, polyetheretherketone, and 3-chloropropyltrimethoxysilane in step (2) to a ball mill for ball milling to obtain mixed particles, and then adding the mixed particles to the adhesive in step (3), stirring at room temperature, and obtaining a highly thermally conductive adhesive after stirring; (5) preparing a copper clad laminate: evenly coating the cut glass fiber cloth with the high thermal conductivity adhesive solution described in step (4), baking it in an oven to obtain a prepreg, cutting the prepregs with a flat surface and even coating according to the size, stacking them neatly, attaching copper foil on both sides, and pressing them in a hot press to obtain the high thermal conductivity copper clad laminate; In parts by weight, the raw materials in step (3) are 60-80 parts of epoxy resin, 10-15 parts of polyphenylene ether powder, 10-20 parts of phthalic anhydride, 10-20 parts of dicyandiamide, 20-40 parts of acetone, and 2-5 parts of triphenylphosphine; In step (4), the mass ratio of the modified inorganic particles, polyetheretherketone, and 3-chloropropyltrimethoxysilane is 100:10-15:1-5; the ball milling speed is 2500-3500 r / min, and the time is 0.5-1h.

2. A process for preparing a high thermal conductivity copper clad laminate according to claim 1, characterized in that: In step (1), the mass ratio of silicon carbide powder to aluminum nitride powder is 1-3:1; the ball milling speed is 1500-3000 r / min, and the time is 2-3 h.

3. A process for preparing a high thermal conductivity copper clad laminate according to claim 1, characterized in that: In step (2), the mass ratio of the pretreated inorganic particles, tetrabutyl titanate, deionized water, sodium dodecylbenzene sulfonate and ammonia water is 10:30-40:50-80:1-2:20-40; the mass concentration of the ammonia water is 20-25%.

4. A process for preparing a high thermal conductivity copper clad laminate according to claim 1, characterized in that: The temperature of the hydrothermal reaction in step (2) is 120-160°C, and the reaction time is 5-10h; the temperature of the calcination is 900-1100°C, and the calcination time is 2-4h.

5. A process for preparing a high thermal conductivity copper clad laminate according to claim 1, characterized in that: The constant temperature stirring in step (3) is 50-70°C, the time is 1-2h, and the stirring speed is 200-300r / min.

6. A process for preparing a high thermal conductivity copper clad laminate according to claim 1, characterized in that: In step (4), the mass ratio of the mixed particles to the glue is 5-10:100; the stirring speed is 300-500 r / min, and the time is 0.5-1 h.

7. A process for preparing a high thermal conductivity copper clad laminate according to claim 1, characterized in that: The baking temperature in step (5) is 60-80°C and the time is 20-40 minutes; the pressing conditions are: temperature 180-240°C, pressure 1-3MPa, and curing time 80-120 minutes.

8. A high thermal conductivity copper clad laminate prepared by the preparation process according to any one of claims 1 to 7.