Copper-clad plate based on polyphenyl ether resin glue solution and preparation process of copper-clad plate

Abstract

The invention discloses a copper-clad plate based on a polyphenyl ether resin glue solution and a preparation process of the copper-clad plate, and particularly belongs to the field of copper-clad plate glue solution manufacturing. The copper-clad plate is prepared by dipping a reinforcing material in a glue solution and then laminating and cladding copper; wherein the glue solution is prepared from the following components in parts by mass: 20 to 40 parts of polyphenyl ether resin, 20 to 35 parts of benzoxazine resin, 2 to 10 parts of curing agent, 0.5 to 1 part of curing accelerator, 50 to 100 parts of diluent and 25 to 30 parts of modified filler; the modified filler provided by the invention can effectively improve the insulating property, the dielectric property and the mechanical property of the copper-clad plate glue solution, and the polytetrafluoroethylene micro powder, the glass fiber powder and the barium sulfate powder in a specific particle size range in the modified filler are simultaneously used in a specific dosage ratio range, so that the modified filler has a certain synergistic effect on the performance of the copper-clad plate.

Description

Technical Field

[0001] The present invention belongs to the field of manufacturing copper clad laminates, and particularly relates to a copper clad laminate based on polyphenylene ether resin solution and its preparation process. Background Art

[0002] Most copper clad laminates use single fillers or simple mixed fillers (such as silica, talcum powder, etc.) to reduce the dielectric constant or enhance the mechanical properties, but there are the following limitations: Firstly, it is difficult for single fillers to meet the comprehensive requirements of high insulation, low dielectric loss and high peel strength; Secondly, uneven particle size distribution of fillers easily leads to poor dispersion, affecting the thermal stability and interfacial bonding strength of copper clad laminates; Thirdly, although traditional fillers (such as inorganic oxides) can reduce the dielectric constant, they are prone to introduce hygroscopicity, reduce the moisture and heat resistance, and have insufficient control over the loss of high-frequency signal transmission. In addition, some researchers have tried to introduce polytetrafluoroethylene (PTFE) to utilize its excellent insulation and chemical inertness, but its compatibility with the resin matrix is poor, and it is difficult to achieve synergistic improvement of mechanical properties when used alone. Summary of the Invention

[0003] Aiming at the deficiencies of the prior art, the purpose of the present invention is to innovatively adopt a strategy of multi-component synergistic modification, and solve the key problems of filler dispersion, interfacial bonding and functional synergy by optimizing the mass ratio and particle size control of polytetrafluoroethylene micropowder, glass fiber powder and barium sulfate powder.

[0004] To achieve the above purpose, the present invention discloses the following solutions:

[0005] In the first aspect, the present invention provides a copper clad laminate based on polyphenylene ether resin solution, which is obtained by impregnating a reinforcing material with the solution and then laminating and copper-cladding.

[0006] By mass, the solution includes the following components:

[0007]

[0008]

[0009] The preparation method of the modified filler includes the following steps:

[0010] 1-1. Pretreatment: Mix polytetrafluoroethylene micropowder, glass fiber powder and barium sulfate powder with a mass ratio of (8-10):(3-5):1 evenly, soak them in 10-15 times the amount of 15wt% sodium hydroxide solution for 1.5h-2.5h, take them out and drain, to obtain the pretreated mixed powder;

[0011] 1-2. Reaction system setup: Mix the pretreated mixed powder and 75 v / v% ethanol aqueous solution at a solid-liquid ratio of 1:(15-20) g / mL to obtain a reaction system;

[0012] 1-3. Primary stirring reaction: Stir the reaction system at (200-300) r / min for 1-2 h under a nitrogen atmosphere at 28°C - 30°C;

[0013] 1-4. Secondary stirring reaction: Add a certain amount of silane coupling agent KH-540 to the reaction system, maintain the nitrogen atmosphere and the same stirring rate, and continue the reaction for 50-70 min, where the addition amount of the silane coupling agent is 5-7% of the total mass of the reaction system;

[0014] 1-5. Temperature-raising reaction: Raise the temperature of the reaction system to 90-100°C, keep the stirring rate, and continue the reaction for 2.5-3.5 h to obtain a reaction product;

[0015] 1-6. Post-treatment: Cool the reaction product to room temperature, centrifuge to obtain a precipitate, and dry the precipitate at 55-65°C for 2.5-3.5 h to obtain the modified filler.

[0016] Preferably, the particle size of the polytetrafluoroethylene micro-powder is 2-5 μm;

[0017] The single-filament major axis of the glass fiber powder is 11-17 μm, the single-filament cross-sectional diameter is 11-17 μm, and the ratio of the single-filament major axis to the diameter is 1:1;

[0018] The particle size of the barium sulfate is 0.7-1 μm.

[0019] Preferably, the benzoxazine resin is a liquid ODA-type benzoxazine resin.

[0020] Preferably, the curing agent is at least one of dicyandiamide and phenolic resin.

[0021] Preferably, the curing accelerator is at least one of 2-methylimidazole and 2-ethyl-4-methylimidazole.

[0022] Preferably, the diluent is at least one of acetone and butanone.

[0023] In the second aspect, the present invention provides a method for preparing the copper clad laminate of the first aspect, including the following steps:

[0024] 2-1. Preparation of adhesive solution: First, dissolve polyphenylene ether resin with a diluent to obtain a polyphenylene ether resin solution. Then, mix the polyphenylene ether resin solution, benzoxazine resin, curing agent, and curing accelerator, and stir at 2000 - 3000 r / min for 30 - 60 min. After adding the modified filler, continue to stir at 4000 r / min for 10 - 30 min to obtain the adhesive solution;

[0025] 2-2. Impregnation and drying: Immerse the reinforcing material in the adhesive solution, and after impregnation, dry it at 100 - 150 °C for 5 - 15 min to obtain a prepreg;

[0026] 2-3. Laminating and molding: Stack the prepreg and copper foil, and hot press at 100 - 150 °C and a pressure of 10 - 20 MPa for 20 - 40 min to obtain the copper clad laminate.

[0027] Preferably, the reinforcing material is at least one of fiberglass cloth and ceramic fiber cloth.

[0028] Preferably, the hot pressing in the laminating and molding is as follows: First, pre-press at 100 - 120 °C for 5 - 10 min, and then raise the temperature to 130 - 150 °C for main pressing for 30 - 40 min.

[0029] Advantages of the present invention:

[0030] The modified filler provided by the present invention can effectively improve the insulation performance, dielectric performance, and mechanical performance of the copper clad laminate adhesive solution. The polytetrafluoroethylene micropowder with a specific particle size range in the modified filler, when used simultaneously with glass fiber powder and barium sulfate powder within a specific dosage ratio range, has a certain synergistic effect on the performance of the copper clad laminate. Detailed implementation manners

[0031] Next, the technical solutions in the present invention will be clearly and completely described in combination with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0032] The following further elaborates on the technical solutions of the present invention in combination with specific embodiments. It should be understood that the following embodiments are only used to explain the present invention and are not used to limit the present invention.

[0033] In the present invention:

[0034] Polytetrafluoroethylene micropowder: The D90 average particle size is 2 - 5 μm, purchased from Shenyang Tianyu Xiang Micropowder Materials Factory. Other particle size micropowders used in the examples are all purchased from this company;

[0035] Polyphenylene ether resin: purchased from Nagase (China) Co., Ltd.;

[0036] Benzoxazine resin: ODA type benzoxazine resin, purchased from Jinan Shengquan Group Co., Ltd.;

[0037] Glass fiber powder: the single filament has a major axis of 11 - 17 μm, a cross-sectional diameter of 11 - 17 μm, and a ratio of major axis to diameter of 1:1, purchased from Weijia Composite Materials Co., Ltd.;

[0038] Barium sulfate powder: the D90 average particle size is 0.7 - 1 μm, purchased from Hongzhi New Materials Co., Ltd.;

[0039] Silane coupling agent: model KH - 540, purchased from Hangzhou Jessica Chemical Co., Ltd.;

[0040] Phenolic resin: dicyclopentadiene phenolic resin, purchased from Jinan Shengquan Group Co., Ltd.;

[0041] In the specific examples, other raw materials are commercially available, and the particle size of the above raw materials can be customized by the suppliers.

[0042] Preparation of modified filler

[0043] Modified filler ①

[0044] Step 1 - 1. Pretreatment: Mix polytetrafluoroethylene micro - powder, glass fiber powder and barium sulfate powder with a mass ratio of 8:3:1 evenly, then soak them in a 10 - fold amount of sodium hydroxide solution with a concentration of 15 wt% for 2 h, take them out and drain to obtain the pretreated mixed powder;

[0045] Step 1 - 2. Setup of reaction system: Add the pretreated mixed powder and 75 v / v% ethanol - aqueous solution into a three - necked flask according to a solid - liquid ratio of 1:20 g / mL to mix and obtain a reaction system. The three - necked flask is equipped with a stirrer, a thermometer and a gas guide tube;

[0046] Step 1 - 3. Primary stirring reaction: Pass nitrogen into the reaction system for protection, and under the constant temperature condition of 28 °C, continuously stir and react at a stirring rate of 200 r / min for 1 h;

[0047] Step 1 - 4. Secondary stirring reaction: Add a certain amount of silane coupling agent KH - 540 into the reaction system, maintain the nitrogen atmosphere and the same stirring rate, and continue to react for 50 min. The addition amount of the silane coupling agent is 5% of the total mass of the reaction system;

[0048] Step 1 - 5. Heating reaction: Heat the reaction system to 93 °C, keep the stirring rate at 200 r / min, and continuously react for 3 h to obtain a reaction product;

[0049] Step 1-6. Post-treatment: Cool the reaction product to room temperature, centrifuge to obtain a precipitate, place the precipitate in a vacuum drying oven, and dry it at 60 °C for 3 h to finally obtain the modified filler ①.

[0050] Modified filler ②

[0051] Step 1-1. Pretreatment: Mix polytetrafluoroethylene micropowder, glass fiber powder, and barium sulfate powder with a mass ratio of 10:5:1 evenly, then soak them in a sodium hydroxide solution with a concentration of 15 wt% and a volume 12 times that of the powder for 1.5 h. After taking them out and draining, obtain the pretreated mixed powder.

[0052] Step 1-2. Setup of reaction system: Add the pretreated mixed powder and 75 v / v% ethanol aqueous solution to a three-necked flask according to a solid-liquid ratio of 1:15 g / mL for mixing to obtain a reaction system. The three-necked flask is equipped with a stirrer, a thermometer, and a gas pipe.

[0053] Step 1-3. Primary stirring reaction: Pass nitrogen into the reaction system for protection, and under the constant temperature condition of 30 °C, continuously stir and react at a stirring rate of 300 r / min for 2 h.

[0054] Step 1-4. Secondary stirring reaction: Add a certain amount of silane coupling agent KH-540 to the reaction system, maintain the nitrogen atmosphere and the same stirring rate, and continue to react for 70 min. The addition amount of the silane coupling agent is 7% of the total mass of the reaction system.

[0055] Step 1-5. Temperature-raising reaction: Raise the temperature of the reaction system to 90 °C, keep the stirring rate at 300 r / min, and continuously react for 2.5 h to obtain a reaction product.

[0056] Step 1-6. Post-treatment: Cool the reaction product to room temperature, centrifuge to obtain a precipitate, place the precipitate in a vacuum drying oven, and dry it at 55 °C for 2.5 h to finally obtain the modified filler ②.

[0057] Modified filler ③

[0058] Step 1-1. Pretreatment: Mix polytetrafluoroethylene micropowder, glass fiber powder, and barium sulfate powder with a mass ratio of 9:4:1 evenly, then soak them in a sodium hydroxide solution with a concentration of 15 wt% and a volume 15 times that of the powder for 2.5 h. The mass ratio of the powder to sodium hydroxide is 1:15. After soaking, take them out and drain to obtain the pretreated mixed powder.

[0059] Step 1-2. Setup of reaction system: Add the pretreated mixed powder and 75 v / v% ethanol aqueous solution to a three-necked flask according to a solid-liquid ratio of 1:17 g / mL for mixing to obtain a reaction system. The three-necked flask is equipped with a stirrer, a thermometer, and a gas pipe.

[0060] Step 1-3. Primary stirring reaction: Introduce nitrogen into the reaction system for protection. Under the constant temperature condition of 29 °C, continuously stir the reaction at a stirring rate of 250 r / min for 1.5 h.

[0061] Step 1-4. Secondary stirring reaction: Add a certain amount of silane coupling agent KH-540 to the reaction system. Maintain the nitrogen atmosphere and the same stirring rate, and continue the reaction for 60 min. The addition amount of the silane coupling agent is 6% of the total mass of the reaction system.

[0062] Step 1-5. Heating reaction: Heat the reaction system to 100 °C, maintain the stirring rate of 250 r / min, and continuously react for 3.5 h to obtain the reaction product.

[0063] Step 1-6. Post-treatment: Cool the reaction product to room temperature, centrifuge to obtain the precipitate, place the precipitate in a vacuum drying oven, and dry it at 65 °C for 3.5 h to finally obtain the modified filler ③.

[0064] In order to verify the influence of each component in the modified filler on the performance of the adhesive solution, the raw materials are defaulted or replaced based on the modified filler ①, as follows:

[0065] Modified filler ④

[0066] Carry out according to the method for preparing the modified filler ①, with the difference that the particle size specification of the polytetrafluoroethylene micropowder is adjusted to an average D90 particle size of ≤1 μm.

[0067] Modified filler ⑤

[0068] Carry out according to the method for preparing the modified filler ①, with the difference that the particle size specification of the polytetrafluoroethylene micropowder is adjusted to an average D90 particle size of ≥6 μm.

[0069] Modified filler ⑥

[0070] Carry out according to the method for preparing the modified filler ①, with the difference that the mass ratio of the polytetrafluoroethylene micropowder, glass fiber powder, and barium sulfate powder in Step 1-1 is adjusted to 3:1:8.

[0071] Modified filler ⑦

[0072] Carry out according to the method for preparing the modified filler ①, with the difference that no glass fiber powder is added in the pretreatment step. After mixing the polytetrafluoroethylene and barium sulfate powder with a mass ratio of 8:1 evenly, continue with the subsequent preparation steps.

[0073] Preparation of copper clad laminate

[0074] Accurately weigh according to the mass parts of the raw materials in Table 1-2;

[0075] 2-1. Preparation of the adhesive solution: First, dissolve the polyphenylene ether resin with a diluent to obtain a polyphenylene ether resin solution. Then, mix the polyphenylene ether resin solution, benzoxazine resin, curing agent, and curing accelerator, and stir at 2500 r / min for 45 min. After adding the modified filler, continue to stir at 4000 r / min for 20 min to obtain the adhesive solution;

[0076] 2-2. Impregnation and drying: Immerse the reinforcing material in the adhesive solution, and after impregnation, dry it at 130 °C for 5 min to obtain a prepreg, where the reinforcing material is a ceramic fiber cloth;

[0077] 2-3. Laminating and molding: Stack the prepreg and copper foil, first pre-press at 120 °C for 10 min, and then raise the temperature to 150 °C for main pressing for 30 min to obtain a copper clad laminate.

[0078] Table 1 Mass parts of raw materials in the examples

[0079]

[0080] Note: "-" in the table indicates no addition.

[0081] Table 2 Mass parts of raw materials in the comparative examples

[0082]

[0083]

[0084] Note: "-" in the table indicates no addition.

[0085] Performance testing

[0086] Perform performance testing on the copper clad laminates prepared in Examples 1-3 and Comparative Examples 1-4.

[0087] The test items are as follows:

[0088] CTI value: Test according to the standard method of 《IEC-112》;

[0089] Peel strength: Test according to the test standard of 《IPC-TM-650》2018;

[0090] Glass transition temperature Tg: Test according to the test standard of 《IPC-TM-650》2018;

[0091] Dielectric constant and dielectric loss: Test according to the specification of 《ASTM D150》;

[0092] The obtained results are shown in Table 3.

[0093] Table 3 Performance test results

[0094] Project / Group Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 CTI value (V) 600 650 600 400 500 350 300 Peel strength (N / mm) 1.632 1.652 1.638 1.283 1.408 1.179 1.113 Tg (°C) 275 278 276 221 229 201 195 Dielectric constant (Dk, 1 GHz) 2.32 2.43 2.34 3.16 3.07 3.24 2.28 Dielectric loss (Df, 1 GHz) 0.0038 0.0040 0.0039 0.0061 0.0056 0.0073 0.0034

[0095] Result analysis:

[0096] According to the results, it can be seen that the particle size of polytetrafluoroethylene micropowder has a significant impact on the performance of the copper clad laminate. When the particle size of polytetrafluoroethylene micropowder is controlled within 2 - 5 μm, the CTI value of the copper clad laminate reaches above 600 V, the peel strength remains above 1.5 N / mm, the glass transition temperature (Tg) is about 275 - 278 °C, and the dielectric constant Dk and dielectric loss Df are 2.32 - 2.43 and 0.0038 - 0.0040 respectively, showing excellent dielectric properties. When the particle size of polytetrafluoroethylene is too small (for example, in Comparative Example 1, polytetrafluoroethylene micropowder with a D90 average particle size ≤ 1 μm is used), the CTI value of the prepared copper clad laminate drops to 400 V and the dielectric constant increases to 3.16, indicating that too small a particle size in this modified filler system will lead to uneven dispersion of the filler, reducing the insulation performance and dielectric characteristics; when the particle size of polytetrafluoroethylene is too large (for example, in Comparative Example 2, polytetrafluoroethylene micropowder with a D90 average particle size ≥ 6 μm is used), the CTI value of the prepared copper clad laminate is 500 V, which is better than that of Comparative Example 1 but still significantly lower than that of the examples, indicating that too large a particle size will reduce the interfacial bonding ability of the filler and affect the comprehensive performance of the material. This shows that the particle size of polytetrafluoroethylene micropowder within the range of 2 - 5 μm can optimize the compatibility between the filler and the matrix, thereby improving the electrical, mechanical and thermal stability of the copper clad laminate.

[0097] The mass ratio of polytetrafluoroethylene micropowder, glass fiber powder and barium sulfate powder in the modified filler has a particularly crucial synergistic effect on the properties of the copper clad laminate. When Examples 1-3 adopt specific mass ratio ranges of polytetrafluoroethylene micropowder, glass fiber powder and barium sulfate powder, all performance indicators are in the optimal range. Among them, the CTI value of Example 2 reaches the highest 650V, the glass transition temperature Tg also reaches the highest 278°C, and the dielectric properties are stable; while in Comparative Example 3, due to the mass ratio of polytetrafluoroethylene, glass fiber powder and barium sulfate not being within the specific range, the CTI value of its copper clad laminate drops sharply to 350V, the Tg is only 201°C, and the dielectric loss Df increases significantly to 0.0073, indicating that the imbalance of the mass ratio will destroy the synergistic effect of the filler, resulting in a comprehensive deterioration of insulation, thermal stability and dielectric properties. In addition, in Comparative Example 4, the lack of glass fiber powder results in the CTI value of its copper clad laminate being only 300V, the peel strength dropping to 1.113N / mm, and the Tg being only 195°C, indicating that glass fiber powder is indispensable for enhancing mechanical strength and improving heat resistance. Polytetrafluoroethylene micropowder provides excellent insulation and chemical stability, glass fiber powder enhances mechanical properties, and barium sulfate powder improves dispersibility, optimizes electrical insulation and dielectric characteristics. None of them can be missing, and they have a certain synergistic effect. Therefore, by adding polytetrafluoroethylene micropowder, glass fiber powder and barium sulfate powder with a mass ratio of (8-10):(3-5):1, the present invention can precisely balance the functions of each component and achieve a comprehensive improvement in the properties of the copper clad laminate.

[0098] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A copper-clad laminate based on polyphenylene ether resin glue, characterized in that: The copper-clad laminate is made by laminating and cladding the reinforcing material with copper after being impregnated with glue; The glue solution comprises the following components by mass: The preparation method of the modified filler comprises the following steps: 1-1 Pretreatment: The mass ratio of (8-10): (3-5): 1 polytetrafluoroethylene powder, glass fiber powder and barium sulfate powder was mixed evenly, placed in 10-15 times the amount, the concentration of 15wt% sodium hydroxide solution was soaked for 1.5h-2.5h, taken out and drained to obtain a pretreated mixed powder; 1-2. Reaction system construction: The pretreated mixed powder and 75v / v% ethanol aqueous solution were mixed at a solid-liquid ratio of 1:(15-20) g / mL to obtain a reaction system; 1-3. Initial stirring reaction: The reaction system was stirred at (200-300) r / min for 1h-2h under nitrogen atmosphere at 28°C-30°C; 1-4. Secondary stirring reaction: Add a certain amount of silane coupling agent KH-540 to the reaction system, maintain a nitrogen atmosphere and the same stirring rate, and continue the reaction for 50min-70min, wherein the amount of silane coupling agent added is 5-7% of the total mass of the reaction system; 1-5. Heating reaction: The reaction system is heated to 90-100°C, the stirring rate is maintained, and the reaction is continued for 2.5-3.5h to obtain a reaction product; 1-6. Post-treatment: The reaction product is cooled to room temperature, centrifuged to obtain a precipitate, and the precipitate is dried at 55-65° C. for 2.5-3.5 hours to obtain the modified filler.

2. The copper clad laminate according to claim 1, characterized in that: The particle size of the polytetrafluoroethylene powder is 2-5 μm; The glass fiber powder has a monofilament major diameter of 11-17 μm, a monofilament cross-sectional diameter of 11-17 μm, and a monofilament major diameter to diameter ratio of 1:1; The particle size of the barium sulfate is 0.7-1 μm.

3. The copper clad laminate according to claim 1, characterized in that: The benzoxazine resin is a liquid ODA type benzoxazine resin.

4. The copper clad laminate according to claim 1, characterized in that: The curing agent is at least one of dicyandiamide and phenolic resin.

5. The copper clad laminate according to claim 1, characterized in that: The curing accelerator is at least one of 2-methylimidazole and 2-ethyl-4-methylimidazole.

6. The copper clad laminate according to claim 1, characterized in that: The diluent is at least one of acetone and butanone.

7. The method for preparing the copper clad laminate according to any one of claims 1 to 6, characterized in that: The following steps are involved: 2-1. Preparation of glue solution: first dissolve the polyphenylene ether resin with a diluent to obtain a polyphenylene ether resin solution, then mix the polyphenylene ether resin solution, benzoxazine resin, curing agent, and curing accelerator, and stir at 2000-3000r / min for 30-60min, add the modified filler, and continue stirring at 4000r / min for 10-30min to obtain the glue solution; 2-2. Impregnation and drying: Impregnate the reinforcing material in the glue solution, and dry it at 100-150℃ for 5-15min to obtain a prepreg; 2-3. Lamination: The prepreg and the copper foil are laminated, and hot pressed at 100-150° C. and 10-20 MPa for 20-40 minutes to obtain the copper clad laminate.

8. The preparation method according to claim 7, characterized in that: The reinforcing material is at least one of glass fiber cloth and ceramic fiber cloth.

9. The preparation method according to claim 7, characterized in that: The hot pressing in the lamination molding is: pre-pressing at 100-120° C. for 5-10 minutes, and then heating to 130-150° C. for main pressing for 30-40 minutes.

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