A method for manufacturing a high-toughness epoxy resin copper-clad plate

Abstract

The application provides a manufacturing method of high-toughness epoxy resin copper-clad plate, mainly including the following steps: preparation of bisphenol fluorene epoxy resin, preparation of resin-based glue solution, preparation of semi-cured sheet and manufacturing of high-toughness epoxy resin copper-clad plate. The high-toughness epoxy resin copper-clad plate prepared by the application has good toughness, heat resistance and corrosion resistance.

Description

Technical Field

[0001] This invention relates to a method for manufacturing copper-clad laminates, and more particularly to a method for manufacturing high-toughness epoxy resin copper-clad laminates. Background Technology

[0002] Copper clad laminate (CCL) is the core substrate material for manufacturing printed circuit boards (PCBs). It is widely used in various electronic devices such as computers, communication equipment, and automotive electronics, primarily serving as insulation, support, and carrier of conductive lines. Epoxy resin has become one of the most widely used matrix resins for copper clad laminates due to its excellent adhesion, electrical insulation, chemical resistance, and relatively low cost.

[0003] However, epoxy resin forms a highly cross-linked three-dimensional network structure after curing, which restricts the movement of molecular chain segments. This results in inherent defects in the cured product, such as high brittleness, poor impact and crack resistance, and high internal stress. When applied to copper-clad laminates, these material science deficiencies directly translate into shortcomings in product performance: during subsequent PCB drilling, cutting, assembly, and use, the board is prone to microcracks or even fractures due to mechanical or thermal stress, seriously affecting the reliability and service life of the product. In particular, the high-frequency vibration and instantaneous overload automotive electronic environment, or the multilayer drilling process of high-density interconnect (HDI) boards, place higher demands on the toughness of copper-clad laminates.

[0004] To improve the toughness of epoxy resins, the industry has conducted extensive research and proposed various toughening modification methods. Traditional methods mainly include adding rubber elastomers (REs), thermoplastics (TPs), core-shell polymers (CSPs), liquid crystal polymers (LCPs) as the second phase dispersion; or introducing rigid inorganic fillers and constructing interpenetrating polymer networks (IPNs). In recent years, novel toughening strategies have also emerged, such as using hyperbranched polymers (HBPs), bio-based materials (BBMs), or modifying the crosslinking network topology (TSs) through molecular design. Some specific patented technical solutions include: reducing crosslinking density and improving toughness by synthesizing epoxy resin solutions with oxazolidinone structures and extending the main chain length; or introducing natural products such as epoxidized lignin into epoxy resin synthesis to improve mechanical properties.

[0005] While existing technologies have improved the toughness of epoxy resin copper-clad laminates to some extent, some limitations and challenges remain. For example, many toughening methods may sacrifice the material's heat resistance (Tg), dimensional stability, dielectric properties (Dk / Df), or processability while improving toughness; some methods offer limited improvements in toughness, making it difficult to meet the increasingly stringent requirements of high-reliability applications. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a method for manufacturing a high-toughness epoxy resin copper-clad laminate, wherein the high-toughness epoxy resin copper-clad laminate obtained therefrom has good toughness, heat resistance and corrosion resistance.

[0007] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows:

[0008] A method for manufacturing a high-toughness epoxy resin copper-clad laminate includes the following steps:

[0009] S1. Add epichlorohydrin, bisphenol fluorene, 1,4-dioxane, and hexadecyltrimethylammonium bromide to a reaction flask, heat to 75-80℃ under nitrogen protection, stir for 30-40 minutes, add sodium hydroxide solution dropwise to the reaction flask within 1 hour, heat to 80-85℃ after the addition is complete, stir for 1-2 hours, and cool to room temperature to obtain the reaction solution;

[0010] S2. After the reaction solution obtained in step S1 is allowed to stand and separate into layers, the upper layer liquid is taken. The upper layer liquid is washed with deionized water until neutral. Epichlorohydrin and 1,4-dioxane are recovered by rotary evaporation and then cooled to room temperature to obtain bisphenol fluorene epoxy resin.

[0011] S3. Add polypropylene carbonate to the bisphenol fluorene epoxy resin obtained in step S2, heat to 150°C and stir for 1-2 hours to obtain the resin matrix;

[0012] S4. Add the accelerator, curing agent, filler, solvent, and siloxane to the resin matrix obtained in step S3, heat to 75-85℃ and stir for 3-4 hours to obtain a resin-based adhesive.

[0013] S5. Immerse the fiberglass cloth in the resin-based adhesive obtained in step S4, remove it and bake it in an oven for 1-2 minutes to obtain a semi-cured sheet;

[0014] S6. Take 4 semi-cured sheets obtained in step S5 and stack them together to obtain a laminate. Cover the top and bottom surfaces of the laminate with a copper foil and place it in a laminator for hot pressing to obtain a high-toughness epoxy resin copper-clad laminate.

[0015] Furthermore, in step S1 of the present invention, the mass concentration of sodium hydroxide solution is 40%, and the ratio of epichlorohydrin, bisphenol fluorene, 1,4-dioxane, hexadecyltrimethylammonium bromide, and sodium hydroxide solution is 48g:18g:80mL:1g:(10-15)mL, and the stirring speed is 300 rpm.

[0016] Furthermore, in step S3 of the present invention, the mass ratio of polypropylene carbonate to bisphenol fluorene epoxy resin obtained in step S2 is 3:1, and the stirring speed is 400-600 rpm.

[0017] Further, in step S4 of the present invention, by mass parts, there are 0.6-1 parts of accelerator, 15-18 parts of curing agent, 12-15 parts of filler, 65-68 parts of solvent, 5-6 parts of siloxane, and 56-60 parts of resin matrix obtained in step S3; the stirring speed is 600-800 rpm.

[0018] Furthermore, in step S4 of the present invention, the accelerator is 2-phenylimidazolium, the curing agent is 4,4'-diaminodiphenylmethane, the filler is hollow glass microspheres with an average particle size of 80-100 μm, the solvent is propylene glycol monomethyl ether, and the siloxane is acetoxypropylheptamethyltrisiloxane.

[0019] Furthermore, in step S5 of the present invention, the glass fiber cloth is grade E glass fiber cloth, and the baking temperature is 170-180℃.

[0020] Furthermore, in step S6 of the present invention, the hot pressing process is as follows: in the first stage, the hot pressing temperature is 150°C and the time is 2 hours; in the second stage, the hot pressing temperature is 170°C and the time is 1.5 hours; in the third stage, the hot pressing temperature is 190°C and the time is 2.5 hours.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1) The epoxy resin in the resin-based adhesive used in this invention is a bisphenol fluorene epoxy resin with a fluorene cyclic side group structure in the main chain. The fluorene cyclic side group structure is a large-volume, rigid structural unit that can improve the rigidity of the molecular chain, increase the steric hindrance, and thus improve the heat resistance and mechanical properties of the copper-clad laminate.

[0023] 2) The polypropylene carbonate in the resin-based adhesive used in this invention is a thermoplastic resin that can form a quasi-interpenetrating network structure with bisphenol fluorene epoxy resin. This structure can induce various energy dissipation mechanisms such as crazing and shear banding when the material is impacted, thereby improving the toughness of the epoxy resin and the copper-clad laminate. Accordingly, step S6 of this invention adopts a multi-stage heating and hot pressing process to allow the resin to flow and impregnate fully, thereby promoting the formation and curing of the quasi-interpenetrating network structure.

[0024] 3) The siloxane in the resin-based adhesive used in this invention—acetyloxypropylheptamethyltrisiloxane—can disperse the internal stress of the resin and improve the toughness, water resistance, and corrosion resistance of the copper-clad laminate. Detailed Implementation

[0025] The present invention will now be described in detail with reference to specific embodiments. The illustrative embodiments and descriptions of the present invention are used to explain the present invention, but are not intended to limit the present invention.

[0026] Example 1

[0027] To manufacture high-toughness epoxy resin copper-clad laminates, follow these steps:

[0028] S1. Epichlorohydrin, bisphenol fluorene, 1,4-dioxane, and hexadecyltrimethylammonium bromide were added to a reaction flask. Under nitrogen protection, the temperature was raised to 78°C, and the mixture was stirred at 300 rpm for 35 minutes. Over one hour, a 40% sodium hydroxide solution was added dropwise to the reaction flask. After the addition was complete, the temperature was raised to 84°C, and the mixture was stirred at 300 rpm for 1.5 hours. The mixture was then cooled to room temperature to obtain the reaction solution. The ratio of epichlorohydrin, bisphenol fluorene, 1,4-dioxane, hexadecyltrimethylammonium bromide, and sodium hydroxide solution was 48 g: 18 g: 80 mL: 1 g: 12 mL.

[0029] S2. After the reaction solution obtained in step S1 is allowed to stand and separate into layers, the upper layer liquid is taken. The upper layer liquid is washed with deionized water until neutral. Epichlorohydrin and 1,4-dioxane are recovered by rotary evaporation and then cooled to room temperature to obtain bisphenol fluorene epoxy resin.

[0030] S3. Add polypropylene carbonate to the bisphenol fluorene epoxy resin obtained in step S2 at a mass ratio of 3:1, heat to 150°C and stir at 500 rpm for 1.5 hours to obtain the resin matrix;

[0031] S4. Add the accelerator, curing agent, filler, solvent, and siloxane to the resin matrix obtained in step S3, heat to 80℃, and stir at 700 rpm for 3.5 hours to obtain a resin-based adhesive; by mass parts, there are 0.8 parts of accelerator, 17 parts of curing agent, 14 parts of filler, 67 parts of solvent, 5.5 parts of siloxane, and 58 parts of the resin matrix obtained in step S3, wherein the accelerator is 2-phenylimidazolium, the curing agent is 4,4'-diaminodiphenylmethane, the filler is hollow glass microspheres with an average particle size of 90 μm, the solvent is propylene glycol monomethyl ether, and the siloxane is acetoxypropylheptamethyltrisiloxane;

[0032] S5. Immerse the E-grade glass fiber cloth (2116) in the resin-based adhesive obtained in step S4, take it out and bake it in an oven at 175°C for 1.5 minutes to obtain a semi-cured sheet;

[0033] S6. Take 4 semi-cured sheets obtained in step S5 and stack them together to obtain a laminate. Cover the top and bottom sides of the laminate with a copper foil (1 oz) respectively, and place it in a laminator for hot pressing to obtain a high-toughness epoxy resin copper-clad laminate. The hot pressing process is as follows: First stage, the hot pressing temperature is 150℃ and the time is 2 hours; Second stage, the hot pressing temperature is 170℃ and the time is 1.5 hours; Third stage, the hot pressing temperature is 190℃ and the time is 2.5 hours.

[0034] Example 2

[0035] To manufacture high-toughness epoxy resin copper-clad laminates, follow these steps:

[0036] S1. Epichlorohydrin, bisphenol fluorene, 1,4-dioxane, and hexadecyltrimethylammonium bromide were added to a reaction flask. Under nitrogen protection, the mixture was heated to 80°C and stirred at 300 rpm for 30 minutes. Over one hour, a 40% sodium hydroxide solution was added dropwise to the reaction flask. After the addition was complete, the mixture was heated to 85°C and stirred at 300 rpm for 1 hour. The mixture was then cooled to room temperature to obtain the reaction solution. The ratio of epichlorohydrin, bisphenol fluorene, 1,4-dioxane, hexadecyltrimethylammonium bromide, and sodium hydroxide solution was 48g:18g:80mL:1g:15mL.

[0037] S2. After the reaction solution obtained in step S1 is allowed to stand and separate into layers, the upper layer liquid is taken. The upper layer liquid is washed with deionized water until neutral. Epichlorohydrin and 1,4-dioxane are recovered by rotary evaporation and then cooled to room temperature to obtain bisphenol fluorene epoxy resin.

[0038] S3. Add polypropylene carbonate to the bisphenol fluorene epoxy resin obtained in step S2 at a mass ratio of 3:1, heat to 150°C and stir at 600 rpm for 1 hour to obtain the resin matrix.

[0039] S4. Add the accelerator, curing agent, filler, solvent, and siloxane to the resin matrix obtained in step S3, heat to 85℃, and stir at 600 rpm for 3 hours to obtain a resin-based adhesive; by mass parts, there are 1 part accelerator, 18 parts curing agent, 15 parts filler, 68 parts solvent, 6 parts siloxane, and 60 parts resin matrix obtained in step S3, wherein the accelerator is 2-phenylimidazolium, the curing agent is 4,4'-diaminodiphenylmethane, the filler is hollow glass microspheres with an average particle size of 100 μm, the solvent is propylene glycol monomethyl ether, and the siloxane is acetoxypropylheptamethyltrisiloxane;

[0040] S5. Immerse the E-grade glass fiber cloth (2116) in the resin-based adhesive obtained in step S4, take it out and put it into an oven at 180°C for 1 minute to obtain a semi-cured sheet;

[0041] S6. Take 4 semi-cured sheets obtained in step S5 and stack them together to obtain a laminate. Cover the top and bottom sides of the laminate with a copper foil (1 oz) respectively, and place it in a laminator for hot pressing to obtain a high-toughness epoxy resin copper-clad laminate. The hot pressing process is as follows: First stage, the hot pressing temperature is 150℃ and the time is 2 hours; Second stage, the hot pressing temperature is 170℃ and the time is 1.5 hours; Third stage, the hot pressing temperature is 190℃ and the time is 2.5 hours.

[0042] Example 3

[0043] To manufacture high-toughness epoxy resin copper-clad laminates, follow these steps:

[0044] S1. Epichlorohydrin, bisphenol fluorene, 1,4-dioxane, and hexadecyltrimethylammonium bromide were added to a reaction flask. Under nitrogen protection, the temperature was raised to 75°C, and the mixture was stirred at 300 rpm for 40 minutes. Over one hour, a 40% sodium hydroxide solution was added dropwise to the reaction flask. After the addition was complete, the temperature was raised to 80°C, and the mixture was stirred at 300 rpm for 2 hours. The mixture was then cooled to room temperature to obtain the reaction solution. The ratio of epichlorohydrin, bisphenol fluorene, 1,4-dioxane, hexadecyltrimethylammonium bromide, and sodium hydroxide solution was 48 g: 18 g: 80 mL: 1 g: 10 mL.

[0045] S2. After the reaction solution obtained in step S1 is allowed to stand and separate into layers, the upper layer liquid is taken. The upper layer liquid is washed with deionized water until neutral. Epichlorohydrin and 1,4-dioxane are recovered by rotary evaporation and then cooled to room temperature to obtain bisphenol fluorene epoxy resin.

[0046] S3. Add polypropylene carbonate to the bisphenol fluorene epoxy resin obtained in step S2 at a mass ratio of 3:1, heat to 150°C and stir at 400 rpm for 2 hours to obtain the resin matrix.

[0047] S4. Add the accelerator, curing agent, filler, solvent, and siloxane to the resin matrix obtained in step S3, heat to 75°C, and stir at 800 rpm for 4 hours to obtain a resin-based adhesive; by mass parts, there are 0.6 parts of accelerator, 15 parts of curing agent, 12 parts of filler, 65 parts of solvent, 5 parts of siloxane, and 56 parts of the resin matrix obtained in step S3, wherein the accelerator is 2-phenylimidazolium, the curing agent is 4,4'-diaminodiphenylmethane, the filler is hollow glass microspheres with an average particle size of 80 μm, the solvent is propylene glycol monomethyl ether, and the siloxane is acetoxypropylheptamethyltrisiloxane;

[0048] S5. Immerse the E-grade glass fiber cloth (2116) in the resin-based adhesive obtained in step S4, take it out and bake it in an oven at 170°C for 2 minutes to obtain a semi-cured sheet;

[0049] S6. Take 4 semi-cured sheets obtained in step S5 and stack them together to obtain a laminate. Cover the top and bottom sides of the laminate with a copper foil (1 oz) respectively, and place it in a laminator for hot pressing to obtain a high-toughness epoxy resin copper-clad laminate. The hot pressing process is as follows: First stage, the hot pressing temperature is 150℃ and the time is 2 hours; Second stage, the hot pressing temperature is 170℃ and the time is 1.5 hours; Third stage, the hot pressing temperature is 190℃ and the time is 2.5 hours.

[0050] Example 4

[0051] To manufacture high-toughness epoxy resin copper-clad laminates, follow these steps:

[0052] S1. Epichlorohydrin, bisphenol fluorene, 1,4-dioxane, and hexadecyltrimethylammonium bromide were added to a reaction flask. Under nitrogen protection, the temperature was raised to 76°C, and the mixture was stirred at 300 rpm for 36 minutes. Over one hour, a 40% sodium hydroxide solution was added dropwise to the reaction flask. After the addition was complete, the temperature was raised to 81°C, and the mixture was stirred at 300 rpm for 1.6 hours. The mixture was then cooled to room temperature to obtain the reaction solution. The ratio of epichlorohydrin, bisphenol fluorene, 1,4-dioxane, hexadecyltrimethylammonium bromide, and sodium hydroxide solution was 48g:18g:80mL:1g:14mL.

[0053] S2. After the reaction solution obtained in step S1 is allowed to stand and separate into layers, the upper layer liquid is taken. The upper layer liquid is washed with deionized water until neutral. Epichlorohydrin and 1,4-dioxane are recovered by rotary evaporation and then cooled to room temperature to obtain bisphenol fluorene epoxy resin.

[0054] S3. Add polypropylene carbonate to the bisphenol fluorene epoxy resin obtained in step S2 at a mass ratio of 3:1, heat to 150°C and stir at 500 rpm for 2 hours to obtain the resin matrix;

[0055] S4. Add the accelerator, curing agent, filler, solvent, and siloxane to the resin matrix obtained in step S3, heat to 78℃, and stir at 700 rpm for 3 hours to obtain a resin-based adhesive; by mass parts, there are 0.9 parts of accelerator, 16 parts of curing agent, 13 parts of filler, 66 parts of solvent, 5.2 parts of siloxane, and 59 parts of the resin matrix obtained in step S3, wherein the accelerator is 2-phenylimidazolium, the curing agent is 4,4'-diaminodiphenylmethane, the filler is hollow glass microspheres with an average particle size of 100 μm, the solvent is propylene glycol monomethyl ether, and the siloxane is acetoxypropylheptamethyltrisiloxane;

[0056] S5. Immerse the E-grade glass fiber cloth (2116) in the resin-based adhesive obtained in step S4, take it out and bake it in an oven at 176°C for 2 minutes to obtain a semi-cured sheet;

[0057] S6. Take 4 semi-cured sheets obtained in step S5 and stack them together to obtain a laminate. Cover the top and bottom sides of the laminate with a copper foil (1 oz) respectively, and place it in a laminator for hot pressing to obtain a high-toughness epoxy resin copper-clad laminate. The hot pressing process is as follows: First stage, the hot pressing temperature is 150℃ and the time is 2 hours; Second stage, the hot pressing temperature is 170℃ and the time is 1.5 hours; Third stage, the hot pressing temperature is 190℃ and the time is 2.5 hours.

[0058] Comparative Example 1

[0059] The difference from Example 1 is that steps S1 and S2 are omitted, and the bisphenol fluorene epoxy resin in step S3 is replaced with E-51 epoxy resin.

[0060] Comparative Example 2

[0061] Unlike Example 1, step S3 is omitted, and the resin matrix used in step S4 is replaced with the bisphenol fluorene epoxy resin obtained in step S2, i.e., polypropylene carbonate is not used.

[0062] Comparative Example 3

[0063] The difference from Example 1 is that the organosilicon—acetyloxypropylheptamethyltrisiloxane—was not used in step S4.

[0064] Experiment Example 1: Toughness Test

[0065] Test reference standard / method: falling weight impact method.

[0066] Testing instrument: Drop hammer impact tester.

[0067] Test objects and targets: The impact area of ​​copper-clad laminates prepared in Examples 1-4 and Comparative Examples 2 and 3 by a drop hammer, wherein the drop hammer height is 1m and the drop hammer mass is 1kg.

[0068] A smaller impact area indicates better toughness. The test results are shown in Table 1.

[0069] Example 1 149 Example 2 148 Example 3 152 Example 4 154 Comparative Example 2 178 Comparative Example 3 172

[0070] Table 1

[0071] As shown in Table 1, the drop hammer impact areas of Examples 1-4 of the present invention are all relatively small, indicating that the high-toughness epoxy resin copper-clad laminate prepared by the present invention has good toughness. The preparation steps of Comparative Examples 2 and 3 are different from those of Example 1. Compared with Example 1, the drop hammer impact areas of Comparative Examples 2 and 3 are all increased, indicating that the polypropylene carbonate and acetoxypropylheptamethyltrisiloxane used in the present invention can effectively improve the toughness of the copper-clad laminate.

[0072] Experiment Example 2: Heat Resistance Test

[0073] Test reference standard / method: DSC method as specified in 2.4.25 of IPC-TM-650.

[0074] Test instrument: Differential scanning calorimeter.

[0075] Test subjects and objectives: Glass transition temperatures of copper-clad laminates prepared in Examples 1-4 and Comparative Example 1.

[0076] A higher glass transition temperature indicates better heat resistance. The test results are shown in Table 2.

[0077] Example 1 196 Example 2 195 Example 3 199 Example 4 202 Comparative Example 1 183

[0078] Table 2

[0079] As can be seen from Table 2, the glass transition temperatures of Examples 1-4 of the present invention are all relatively high, indicating that the high-toughness epoxy resin copper-clad laminate prepared by the present invention has good heat resistance. The preparation steps of Comparative Example 1 are different from those of Example 1. Compared with Example 1, the glass transition temperature of Comparative Example 1 is lower, indicating that the bisphenol fluorene epoxy resin used in the present invention can effectively improve the heat resistance of the copper-clad laminate.

[0080] Experiment Example 3: Mechanical Property Testing

[0081] Test reference standard / method: 2.4.4 of IPC-TM-650 standard.

[0082] Testing instrument: Universal testing machine.

[0083] Test objects and objectives: Bending strength of copper-clad laminates prepared in Examples 1-4, Comparative Examples 1 and 3.

[0084] Higher bending strength indicates better mechanical properties. The test results are shown in Table 3.

[0085] Example 1 513.8 Example 2 515.7 Example 3 520.8 Example 4 521.4 Comparative Example 1 489.5 Comparative Example 3 513.2

[0086] Table 3

[0087] As can be seen from Table 3, the bending strength of Examples 1-3 of the present invention is relatively high, indicating that the high-toughness epoxy resin copper-clad laminate prepared by the present invention has good mechanical properties. The preparation steps of Comparative Example 1 are different from those of Example 1. Compared with Example 1, the bending strength of Comparative Example 1 is lower, indicating that the bisphenol fluorene epoxy resin used in the present invention can effectively improve the mechanical properties of the copper-clad laminate.

[0088] Experiment Example 4: Water Resistance Test

[0089] Test reference standard / method: IPC-TM-650 standard 2.6.2.1.

[0090] Test subjects and objectives: Water absorption rate of copper-clad laminates prepared in Examples 1-4 and Comparative Example 3.

[0091] A lower water absorption rate indicates better water resistance. The test results are shown in Table 4.

[0092] Example 1 0.83 Example 2 0.79 Example 3 0.86 Example 4 0.87 Comparative Example 3 1.03

[0093] Table 4

[0094] As shown in Table 4, the water absorption rates of Examples 1-3 of the present invention are all low, indicating that the high-toughness epoxy resin copper-clad laminate prepared by the present invention has good water resistance. The preparation steps of Comparative Example 3 are different from those of Example 1. Compared with Example 1, the water absorption rate of Comparative Example 3 is lower, indicating that the acetoxypropylheptamethyltrisiloxane used in the present invention can effectively improve the water resistance of the copper-clad laminate.

[0095] Experiment Example 5: Corrosion Resistance Test

[0096] Test method: Immerse the copper-clad laminate in 18% hydrochloric acid for 2 hours, remove it, wash it with water until neutral, and dry it at 100℃ for 1 hour. Refer to Experiment Example 3 to determine the bending strength again, and record it as the bending strength after corrosion. Calculate the bending strength retention rate according to the following formula:

[0097] Bending strength retention rate = (Bending strength after corrosion / Original bending strength) × 100%

[0098] In the formula, the original bending strength was measured by Experiment Example 3.

[0099] Test objects and objectives: the flexural strength retention rate of the copper-clad laminates prepared in Examples 1-4 and Comparative Example 3.

[0100] A higher flexural strength retention rate indicates better corrosion resistance. The test results are shown in Table 5.

[0101] Example 1 95.3 Example 2 96.1 Example 3 95.0 Example 4 94.9 Comparative Example 3 90.5

[0102] Table 5

[0103] As shown in Table 5, the flexural strength retention rates of Examples 1-3 of the present invention are all high, indicating that the high-toughness epoxy resin copper-clad laminate prepared by the present invention has good corrosion resistance. The preparation steps of Comparative Example 3 are different from those of Example 1. Compared with Example 1, the flexural strength retention rate of Comparative Example 3 is lower, indicating that the acetoxypropylheptamethyltrisiloxane used in the present invention can effectively improve the corrosion resistance of the copper-clad laminate.

[0104] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A method for manufacturing a high-toughness epoxy resin copper-clad laminate, characterized in that: Includes the following steps: S1. Add epichlorohydrin, bisphenol fluorene, 1,4-dioxane, and hexadecyltrimethylammonium bromide to a reaction flask, heat to 75-80℃ under nitrogen protection, stir for 30-40 minutes, add sodium hydroxide solution dropwise to the reaction flask within 1 hour, heat to 80-85℃ after the addition is complete, stir for 1-2 hours, and cool to room temperature to obtain the reaction solution; S2. After the reaction solution obtained in step S1 is allowed to stand and separate into layers, the upper layer liquid is taken. The upper layer liquid is washed with deionized water until neutral. Epichlorohydrin and 1,4-dioxane are recovered by rotary evaporation and then cooled to room temperature to obtain bisphenol fluorene epoxy resin. S3. Add polypropylene carbonate to the bisphenol fluorene epoxy resin obtained in step S2, heat to 150°C and stir for 1-2 hours to obtain the resin matrix; S4. Add the accelerator, curing agent, filler, solvent, and siloxane to the resin matrix obtained in step S3, heat to 75-85℃ and stir for 3-4 hours to obtain a resin-based adhesive. S5. Immerse the fiberglass cloth in the resin-based adhesive obtained in step S4, remove it and bake it in an oven for 1-2 minutes to obtain a semi-cured sheet; S6. Take 4 semi-cured sheets obtained in step S5 and stack them together to obtain a laminate. Cover the top and bottom surfaces of the laminate with a copper foil and place it in a laminator for hot pressing to obtain a high-toughness epoxy resin copper-clad laminate.

2. The method for manufacturing a high-toughness epoxy resin copper-clad laminate according to claim 1, characterized in that: In step S1, the mass concentration of sodium hydroxide solution is 40%, and the ratio of epichlorohydrin, bisphenol fluorene, 1,4-dioxane, hexadecyltrimethylammonium bromide, and sodium hydroxide solution is 48g:18g:80mL:1g:(10-15)mL. The stirring speed is 300 rpm.

3. The method for manufacturing a high-toughness epoxy resin copper-clad laminate according to claim 1, characterized in that: In step S3, the mass ratio of polypropylene carbonate to bisphenol fluorene epoxy resin obtained in step S2 is 3:1, and the stirring speed is 400-600 rpm.

4. The method for manufacturing a high-toughness epoxy resin copper-clad laminate according to claim 1, characterized in that: In step S4, by mass percentage, there are 0.6-1 parts of accelerator, 15-18 parts of curing agent, 12-15 parts of filler, 65-68 parts of solvent, 5-6 parts of siloxane, and 56-60 parts of resin matrix obtained in step S3; the stirring speed is 600-800 rpm.

5. The method for manufacturing a high-toughness epoxy resin copper-clad laminate according to claim 4, characterized in that: In step S4, the accelerator is 2-phenylimidazolium, the curing agent is 4,4'-diaminodiphenylmethane, the filler is hollow glass microspheres with an average particle size of 80-100 μm, the solvent is propylene glycol monomethyl ether, and the siloxane is acetoxypropylheptamethyltrisiloxane.

6. The method for manufacturing a high-toughness epoxy resin copper-clad laminate according to claim 1, characterized in that: In step S5, the fiberglass cloth is grade E fiberglass cloth, and the baking temperature is 170-180℃.

7. The method for manufacturing a high-toughness epoxy resin copper-clad laminate according to claim 1, characterized in that: In step S6, the hot pressing process is as follows: in the first stage, the hot pressing temperature is 150°C and the time is 2 hours; in the second stage, the hot pressing temperature is 170°C and the time is 1.5 hours. In the third stage, the hot pressing temperature is 190℃ and the time is 2.5 hours.