Epoxy soybean oil modified phenolic resin composition for cem-3 copper clad plate and application thereof

Abstract

The application discloses an epoxy soybean oil modified phenolic resin composition for CEM-3 copper-clad plates and application thereof, which comprises epoxy soybean oil modified phenolic resin, epoxy resin, amino triazine modified phenolic resin, phosphorus flame retardant, inorganic flame retardant filler and additives; the epoxy soybean oil modified phenolic resin is a reaction type modified resin obtained by ring-opening addition reaction of epoxy soybean oil and phenolic compounds and further polycondensation with formaldehyde. Through the synergy of the epoxy soybean oil modified phenolic resin, the epoxy resin and the amino triazine modified phenolic resin, and the N / P / Mg / Al four-element synergistic flame retardant system, the heat resistance of the prepared CEM-3 copper-clad plate can reach 290 DEG C / 300 seconds or above without blistering and delamination, the size error after etching is less than or equal to 0.08 mm / m, the flame retardant grade reaches UL94 V-0 level, and Tg is greater than or equal to 165 DEG C. The resin composition is compatible with the existing CEM-3 production line impregnation, semi-curing and hot pressing process, and is suitable for the manufacture of CEM-3 copper-clad plates with high requirements for heat resistance and size stability.

Description

Technical Field

[0001] This invention relates to the field of rigid copper-clad laminates for printed circuits, specifically to an epoxy soybean oil modified phenolic resin composition for CEM-3 copper-clad laminates and its application. Background Technology

[0002] CEM-3 (Composite Epoxy Material-3) copper clad laminates are widely used in LED lighting, automotive electronics, home appliance control boards, and 5G communication equipment due to their excellent machinability, electrical insulation, and heat resistance. With the increasing adoption of lead-free soldering processes and the development of electronic devices towards higher power density and higher reliability, higher requirements are being placed on the heat resistance, dimensional stability, and environmental performance of CEM-3 copper clad laminates.

[0003] Currently, the resin system for CEM-3 copper clad laminates mainly faces the following technical bottlenecks:

[0004] 1. Insufficient heat resistance: Traditional CEM-3 sheets use an epoxy / phenolic resin system, which can only meet the short-term welding conditions of 260℃ / 10 seconds. It is difficult to meet the heat shock resistance requirements of 290℃ / 300 seconds or more in high-temperature scenarios such as new energy vehicles and 5G base stations.

[0005] 2. Poor dimensional stability: Conventional resins have high internal stress after curing, resulting in high board warpage (warpage ≥ 1.5%). Dimensional errors are difficult to control within 0.08 mm / m, which cannot meet the requirements of precision electronic packaging.

[0006] 3. The conflict between environmental protection and cost: Existing high heat-resistant systems mostly rely on phosphorus- or bromine-containing flame retardants, which, while meeting flame retardant requirements, pose environmental risks or are too costly. Meanwhile, the market penetration of domestically produced CEM-3 copper clad laminates is limited due to the high production cost of glass fiber mat.

[0007] Some technologies have already attempted to introduce bio-based materials into the field of copper clad laminates.

[0008] For example, Chinese patent CN104448718A discloses a resin composition. Although this technology introduces bio-based components, its resin system is mainly composed of phosphorus-modified phenolic epoxy resin (accounting for 70-90 parts), and epoxidized soybean oil-modified epoxy resin is only used as an auxiliary toughening component (10-30 parts). It fails to give full play to the synergistic effect of the long-chain structure of soybean oil and other resins.

[0009] For example, Chinese patent CN102408673B discloses a resin composition containing epoxidized soybean oil modified phenolic resin and nitrogen-containing phenolic resin for preparing paper-based copper-clad laminates. However, this technical solution has the following limitations: (1) The ring-opening addition reaction and the polycondensation reaction are carried out in the same temperature range (80-90℃), and the two-step reaction is not controlled by separate temperature steps. The degree of ring-opening reaction of epoxidized soybean oil is limited. The reaction temperature of 80-90℃ is insufficient to drive the full ring-opening reaction of epoxidized soybean oil epoxy groups and phenolic hydroxyl groups, resulting in some epoxidized soybean oil epoxy groups not participating in the reaction. In the end, there is unreacted free epoxidized soybean oil in the resin, which affects the uniformity and heat resistance of the cured product; (2) The resin composition does not contain epoxy resin, and the cured body (2) It relies on phenolic self-condensation, and the crosslinking density is insufficient, making it difficult to meet the requirements of CEM-3 copper clad laminate for high heat resistance (above 290℃ / 300 seconds); (3) The nitrogen-containing phenolic resin is modified with melamine, and the nitrogen content is only 4-6%. The product is non-flame retardant and cannot meet the UL94V-0 flame retardant requirements; (4) The application field is paper-based copper clad laminate. The wetting characteristics and curing shrinkage behavior of its substrate (wood pulp paper) are fundamentally different from those of CEM-3 composite substrate (glass fiber felt + glass fiber cloth). This resin system cannot be directly used for the preparation of CEM-3 copper clad laminate.

[0010] Therefore, developing a resin composition for CEM-3 copper clad laminates that can utilize the toughening and cost advantages of soybean oil, and can synergize with specific resin systems to achieve high heat resistance, high dimensional stability, and controllable cost remains a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0011] To address the aforementioned shortcomings of existing technologies, this invention provides an epoxy soybean oil-modified phenolic resin composition for CEM-3 copper clad laminates. By combining an epoxy soybean oil-modified phenolic resin solution, epoxy resin, and aminotriazine-modified phenolic resin, the problem of insufficient heat resistance is solved. Furthermore, by introducing epoxide soybean oil into the phenolic resin backbone through a chemical reaction to form a reactive modified resin for toughening, the problem of poor dimensional stability is resolved. Finally, by combining aminotriazine-modified phenolic resin, a phosphorus-based flame retardant, and a magnesium-aluminum composite inorganic flame retardant filler, an N / P / Mg / Al quaternary flame retardant system is formed, achieving halogen-free flame retardancy. This results in a resin composition for CEM-3 copper clad laminates that exhibits high heat resistance, high dimensional stability, and controllable cost.

[0012] To achieve the above objectives, the present invention provides the following technical solution: an epoxy soybean oil modified phenolic resin composition for CEM-3 copper clad laminates, comprising, by weight, the following components: 60-85 parts epoxy soybean oil modified phenolic resin solution, 10-50 parts epoxy resin, 5-35 parts aminotriazine modified phenolic resin, 20-60 parts inorganic flame retardant filler, 4-15 parts phosphorus-based flame retardant, 1-3 parts additives, and the balance being a first solvent; wherein the epoxy soybean oil modified phenolic resin is a reactive modified phenolic resin obtained by ring-opening reaction of epoxy soybean oil with phenolic compounds, followed by condensation reaction with formaldehyde; and the inorganic flame retardant filler is a compound of magnesium hydroxide and aluminum hydroxide.

[0013] Furthermore, the solid content of the epoxy soybean oil modified phenolic resin solution is 68-72%, and the epoxy equivalent is 400-500 g / eq; the epoxy soybean oil modified phenolic resin is prepared through the following steps:

[0014] Step 1: 20-30 parts by weight of epoxidized soybean oil and 40-60 parts by weight of phenolic compounds are reacted at 100-140℃ for 1-3 hours under the action of 0.1-0.5 parts by weight of the first catalyst, so that the epoxy group of epoxidized soybean oil and the phenolic hydroxyl group of phenolic compound undergo a ring-opening addition reaction to obtain an intermediate containing phenolic ether bond and secondary hydroxyl group.

[0015] Step 2: Cool the intermediate to below 50°C, add 120-160 parts by weight of formaldehyde aqueous solution, 10-30 parts by weight of phenolic compound and 0.1-0.5 parts by weight of second catalyst, heat to 90-100°C to carry out polycondensation reaction until the gelation time reaches 140-160s at 150°C.

[0016] Step 3: Vacuum dehydration until the gelation time reaches 100-120 seconds at 150℃;

[0017] Step 4: Cool to below 70°C, add a second solvent to adjust the solid content to 68-72%.

[0018] Furthermore, the phenolic compound is one or more of phenol, bisphenol A, alkyl-substituted phenol, and cashew phenol; the first catalyst is one or two of triethylamine and triethanolamine; the second catalyst is one or two of ammonia and ethylenediamine; and the second solvent is one or two of methyl ethyl ketone and acetone.

[0019] Furthermore, the epoxy resin is a mixture of phenolic epoxy resin and bisphenol A type epoxy resin, with a mass ratio of phenolic epoxy resin to bisphenol A type epoxy resin E-51 of 4:1 and a solid content of 100%.

[0020] Furthermore, the aminotriazine-modified phenolic resin is a solid resin obtained by condensation reaction of one or two of benzoguanidine and acetylguanidine with phenolic resin, with a hydroxyl equivalent of 120-140 g / eq, a nitrogen content of 12-18%, and a softening point of 100-130℃.

[0021] Furthermore, in the inorganic flame retardant filler, the mass ratio of aluminum hydroxide to magnesium hydroxide is 1:(2-3.5).

[0022] Furthermore, the phosphorus-based flame retardant is one or more of triphenyl phosphate, bisphenol A-bis(diphenyl phosphate), resorcinol-bis(diphenyl phosphate), and resorcinol-bis[bis(2,6-dimethylphenyl) phosphate].

[0023] Furthermore, the first solvent is one or both of propylene glycol methyl ether and propylene glycol monomethyl ether acetate.

[0024] Furthermore, the adjuvant contains 0.5-1.0 parts of dispersant, 0.5-1.0 parts of silane coupling agent, and 0.1-0.5 parts of 2-methylimidazole accelerator.

[0025] Furthermore, the preparation method of the CEM-3 copper clad laminate epoxy soybean oil modified phenolic resin composition is as follows: epoxy soybean oil modified phenolic resin, epoxy resin, aminotriazine modified phenolic resin, inorganic flame retardant filler, phosphorus flame retardant, additives, and first solvent are dispersed in a high-speed disperser at a speed of 1000-3000 r / min for 40-80 min, and the viscosity is adjusted to 80-200 mPa·s@25℃ to obtain resin solution.

[0026] On the other hand, a CEM-3 copper clad laminate has an insulating layer comprising a cured layer obtained by impregnating the resin composition with reinforcing material and hot pressing it. The reinforcing material includes a core reinforcing material and a surface reinforcing material. The core reinforcing material is 75-105 g / m² glass fiber mat, and the surface reinforcing material is 7628-7638 type electronic grade glass fiber cloth.

[0027] Furthermore, the preparation method of the CEM-3 copper clad laminate includes the following steps:

[0028] S1: Impregnate electronic-grade glass fiber cloth with the resin solution, controlling the resin content of the cloth to be 45-50%; impregnate glass fiber mat with the resin solution, controlling the resin content of the mat to be 65-70%; dry the impregnated electronic-grade glass fiber cloth and glass fiber mat in an oven at 155-230℃ to obtain glass cloth semi-cured sheet and glass mat semi-cured sheet.

[0029] S2: Stack 1-4 glass mat prepreg sheets with 2 glass cloth prepreg sheets, and cover the top and bottom with 12-35μm electronic copper foil to obtain the laminated material;

[0030] S3: The laminated materials are hot-pressed in a vacuum hot press at 160-180℃ and 4-6MPa for 85-100 minutes to obtain CEM-3 copper clad laminate.

[0031] The epoxy soybean oil modified phenolic resin composition for CEM-3 copper clad laminates of the present invention has the following beneficial effects:

[0032] 1. This invention conducts the ring-opening addition reaction (100-140℃) and formaldehyde condensation reaction (90-100℃) of epoxidized soybean oil in steps at different temperature ranges: the high-temperature range (100-140℃) ensures the full ring-opening reaction between the epoxy groups and phenolic hydroxyl groups of the epoxidized soybean oil, improving the chemical bonding rate of the epoxidized soybean oil chain segments; the medium-temperature range (90-100℃) allows for controlled condensation, preserving sufficient reactive sites for subsequent co-curing with epoxy resin. This stepwise temperature control strategy differs from the one-step reaction method in the prior art, which operates at a single temperature range of 80-90℃, thus improving the structural controllability and performance consistency of the modified phenolic resin from the source.

[0033] 2. This invention introduces epoxy resin to form a ternary co-cured network. Experiments have shown that binary systems without epoxy resin cannot be molded or have poor performance on CEM-3 copper-clad laminates. However, the ternary system of this invention, with its phenolic hydroxyl groups and residual epoxy groups in the epoxy-modified soybean oil phenolic resin, can form multiple crosslinking points with the epoxy groups of the epoxy resin, the phenolic hydroxyl groups in the aminotriazine-modified phenolic resin, and the active nitrogen on the triazine ring, constructing a three-dimensional interpenetrating network structure. The epoxy soybean oil segments act as internal toughening agents in the network, reducing curing shrinkage; the benzoguanamine-modified phenolic resin, due to the simultaneous presence of the nitrogen-containing rigid structure of the triazine ring and the aromatic structure of the benzene ring in its molecule, contributes to both nitrogen-containing flame retardancy and high thermal stability; the epoxy resin, as the main crosslinking bridging component, ensures the density and heat resistance of the cured network. The synergistic effect of these three components gives the cured system high heat resistance, low internal stress, and good dimensional stability.

[0034] 3. This invention uses benzoguanidine (or acetylguanidine) modified phenolic resin, which has a high nitrogen content (12-18%), providing a higher nitrogen-containing flame retardant contribution at the same dosage. At the same time, the benzene ring substituents of benzoguanidine endow the modified phenolic resin with better organic solvent solubility and compatibility with epoxy resin, which is beneficial to the uniform formulation of the resin composition.

[0035] 4. This invention combines aminotriazine-modified phenolic resin (N source), phosphorus-based flame retardant (P source), magnesium hydroxide, and aluminum hydroxide (Mg / Al source) to form comprehensive flame-retardant protection covering both gas-phase and condensed-phase flame retardancy, achieving a halogen-free flame-retardant UL94 V-0 rating, filling the gap in prior art which could only produce non-flame-retardant products. Its flame-retardant mechanism is as follows:

[0036] (1) Gas-phase flame retardancy: Phosphorus-based flame retardants (such as BDP) generate phosphoric acid, metaphosphoric acid, and polyphosphoric acid free radical scavengers during thermal decomposition, which capture active free radicals such as H· and OH· in the gas phase, interrupting the chain combustion reaction. The triazine ring in aminotriazine-modified phenolic resin releases nitrogen-containing inert gases (such as N2 and NH3) during thermal decomposition, diluting the concentration of combustible gases and carrying away heat. The combined effect of phosphorus-based and nitrogen-containing components in the gas phase makes the free radical scavenging efficiency and gas dilution effect better than those of a single component.

[0037] (2) Condensed phase flame retardancy: The polyphosphoric acid generated by the thermal decomposition of phosphorus-based flame retardants promotes the dehydration and carbonization of the substrate in the condensed phase, forming a dense carbon layer barrier. Magnesium hydroxide (decomposition temperature about 340℃) and aluminum hydroxide (decomposition temperature about 220℃) undergo endothermic dehydration reactions in different temperature ranges, continuously absorbing heat and reducing the surface temperature of the material over a wide temperature range. At the same time, the magnesium oxide and aluminum oxide generated by dehydration are deposited on the surface of the carbon layer, significantly enhancing the density and thermal stability of the carbon layer.

[0038] (3) Gradient flame retardancy: Aluminum hydroxide first dehydrates and absorbs heat at around 220℃, inhibiting the initial temperature rise of the material; magnesium hydroxide continues to dehydrate at around 340℃, providing continuous heat absorption protection in the higher temperature range. This gradient heat absorption decomposition characteristic, combined with the catalytic char formation of phosphorus-based flame retardants and the gas-phase dilution effect of nitrogen-containing components, forms a full-process flame retardant protection from low temperature to high temperature.

[0039] The CEM-3 copper clad laminate of the present invention has the following beneficial effects: The comprehensive performance of the CEM-3 copper clad laminate of experimental group 1 of the present invention is as follows: heat resistance 335 seconds (290℃), dimensional stability 0.06mm / m, Tg 187℃, CTE 28 ppm / ℃, and flame retardant rating UL94 V-0. Detailed Implementation

[0040] The technical solution of the present invention will be clearly and completely described below. The described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Example 1

[0041] This embodiment provides an epoxy soybean oil modified phenolic resin composition for CEM-3 copper clad laminates, comprising the following components by weight: 60-85 parts epoxy soybean oil modified phenolic resin solution, 10-50 parts epoxy resin, 5-35 parts aminotriazine modified phenolic resin, 20-60 parts inorganic flame retardant filler, 4-15 parts phosphorus-based flame retardant, 1-3 parts additives, and the balance being a first solvent; the epoxy soybean oil modified phenolic resin is a reactive modified phenolic resin obtained by ring-opening reaction of epoxy soybean oil and phenolic compounds, followed by condensation reaction with formaldehyde; the inorganic flame retardant filler is a compound of magnesium hydroxide and aluminum hydroxide.

[0042] The resin composition of this embodiment achieves high heat resistance, low internal stress, and good dimensional stability through a ternary co-curing network of epoxidized soybean oil-modified phenolic resin, epoxy resin, and aminotriazine-modified phenolic resin. Furthermore, by incorporating an N / P / Mg / Al quaternary flame-retardant system, a halogen-free UL94 V-0 flame-retardant rating is achieved.

[0043] In this embodiment, the solid content of the epoxy soybean oil modified phenolic resin solution is 68-72%, and the epoxy equivalent is 400-500 g / eq; the epoxy soybean oil modified phenolic resin is prepared through the following steps:

[0044] Step 1: 20-30 parts by weight of epoxidized soybean oil and 40-60 parts by weight of phenolic compounds are reacted at 100-140℃ for 1-3 hours under the action of 0.1-0.5 parts by weight of the first catalyst, so that the epoxy group of epoxidized soybean oil and the phenolic hydroxyl group of phenolic compound undergo a ring-opening addition reaction to obtain an intermediate containing phenolic ether bond and secondary hydroxyl group.

[0045] Step 2: Cool the intermediate to below 50°C, add 120-160 parts by weight of formaldehyde aqueous solution (mass concentration 36%~38%), 10-30 parts by weight of phenolic compound and 0.1-0.5 parts by weight of second catalyst, heat to 90-100°C to carry out polycondensation reaction until the gelation time reaches 140-160s at 150°C;

[0046] Step 3: Vacuum dehydration until the gelation time reaches 100-120 seconds at 150℃;

[0047] Step 4: Cool to below 70°C, add a second solvent to adjust the solid content to 68-72%.

[0048] The preparation method of the epoxidized soybean oil modified phenolic resin adopts a stepwise temperature-controlled synthesis technology. The high-temperature stage (100-140℃) ensures sufficient ring-opening reaction between the epoxy groups of the epoxidized soybean oil and the phenolic hydroxyl groups, improving the chemical bonding rate. The medium-temperature stage (90-100℃) performs controlled polycondensation, preserving reactive sites. This avoids the incomplete reaction and free epoxidized soybean oil issues associated with the one-step reaction (80-90℃). The resulting epoxidized soybean oil modified phenolic resin has an epoxy equivalent of 400-500 g / eq, a solid content of 68-72%, a controllable structure, and consistent performance.

[0049] In this embodiment, the phenolic compound is one or more of phenol, bisphenol A, alkyl-substituted phenols, and cashew phenol; the phenolic compound provides reactive sites to meet different cost and performance requirements.

[0050] In this embodiment, the first catalyst is one or both of triethylamine and triethanolamine; the second catalyst is one or both of ammonia and ethylenediamine; the first catalyst promotes the ring-opening reaction; the second catalyst promotes the polycondensation reaction, resulting in high reaction efficiency and few side reactions.

[0051] In this embodiment, the second solvent is one or both of methyl ethyl ketone and acetone.

[0052] In this embodiment, the epoxy resin is a mixture of phenolic epoxy resin and bisphenol A type epoxy resin, with a mass ratio of phenolic epoxy resin to bisphenol A type epoxy resin E-51 of 4:1 and a solid content of 100%. The phenolic epoxy resin provides a high crosslinking density and acts as a crosslinking bridging component, enhancing the thermal stability and mechanical strength of the cured network. The bisphenol A type epoxy resin E-51 is used to adjust the system viscosity; it forms an interpenetrating network structure with the epoxy soybean oil-modified phenolic resin and the aminotriazine-modified phenolic resin, improving Tg and flexural strength.

[0053] In this embodiment, the aminotriazine-modified phenolic resin is a solid resin obtained by condensation reaction of one or both of benzoguanidine and acetylguanidine with phenolic resin. It has a nitrogen content of 12-18%. The benzoguanidine / acetylguanidine modification, with a nitrogen content of 12-18%, is significantly higher than that of melamine modification (4-6%), resulting in a substantial contribution to flame retardancy. The aminotriazine-modified phenolic resin has a hydroxyl equivalent of 120-140 g / eq; a softening point of 100-130℃; good compatibility with epoxy resin, facilitating uniform formulation of the resin composition; and is a pale yellow to light brown solid. The benzoguanidine / acetylguanidine modification also provides rigid crosslinking nodes, improving Tg and flexural strength.

[0054] In this embodiment, the mass ratio of aluminum hydroxide to magnesium hydroxide in the inorganic flame-retardant filler is 1:(2-3.5). Aluminum hydroxide (decomposes at 220℃) and magnesium hydroxide (decomposes at 340℃) create a gradient endothermic effect, covering a wider temperature range. A mass ratio of 1:(2-3.5) achieves the optimal balance between flame retardancy and heat resistance.

[0055] In this embodiment, the phosphorus-based flame retardant is one or more of triphenyl phosphate (TPP), bisphenol A-bis(diphenyl phosphate) (BDP), resorcinol-bis(diphenyl phosphate) (RDP), and resorcinol-bis[bis(2,6-dimethylphenyl)phosphate] (RDX). Phosphorus-based flame retardants can capture free radicals in the gas phase, interrupting the combustion chain reaction; and form a N / P / Mg / Al quaternary synergy with nitrogen-containing resins and inorganic fillers to achieve highly efficient halogen-free flame retardancy.

[0056] In this embodiment, the adjuvant comprises 0.5-1.0 parts of dispersant, 0.5-1.0 parts of silane coupling agent, and 0.1-0.5 parts of 2-methylimidazole accelerator.

[0057] In this embodiment, the first solvent is one or both of propylene glycol methyl ether (PM) and propylene glycol monomethyl ether acetate (PMA).

[0058] In this embodiment, the preparation method of the epoxidized soybean oil modified phenolic resin composition for CEM-3 copper clad laminate is as follows: epoxidized soybean oil modified phenolic resin, epoxy resin, aminotriazine modified phenolic resin, inorganic flame retardant filler, phosphorus flame retardant, additives, and first solvent are dispersed in a high-speed disperser at a speed of 1000-3000 r / min for 40-80 min, and the viscosity is adjusted to 80-200 mPa·s to obtain the resin composition slurry. Example 2

[0059] This embodiment provides a CEM-3 copper-clad laminate, the insulating layer of which comprises a cured layer obtained by impregnating a reinforcing material with the resin composition described in Example 1 and hot-pressing it. The reinforcing material includes a core reinforcing material and a face reinforcing material. The core reinforcing material is glass fiber mat, and the face reinforcing material is electronic-grade glass fiber cloth. The preparation method of the CEM-3 copper-clad laminate includes the following steps:

[0060] S1: Impregnate 7628-7638 type electronic grade glass fiber cloth with the resin solution, controlling the resin content of the cloth to be 45-50%; impregnate glass fiber mat with a basis weight of 75-105 g / m² with the resin solution, controlling the resin content of the mat to be 65-70%;

[0061] S2: Dry the impregnated electronic-grade glass fiber cloth and glass fiber mat in an oven at 155-230℃ to obtain glass cloth semi-cured sheets and glass mat semi-cured sheets.

[0062] S3: Stack 1-4 glass mat prepreg sheets with 2 glass cloth prepreg sheets, and cover the top and bottom with 12-35μm electronic copper foil to obtain the laminated material;

[0063] S4: The laminated materials are hot-pressed in a vacuum hot press at 160-180℃ and 4-6MPa for 85-100 minutes to obtain CEM-3 copper clad laminate.

[0064] The CEM-3 copper clad laminate has a heat resistance of over 290℃ / 300 seconds without bubbling or delamination, a dimensional error of ≤0.08mm / m, and a flame retardant rating of UL94 V-0.

[0065] The beneficial effects of the epoxidized soybean oil modified phenolic resin composition and CEM-3 copper clad laminate of the present invention will be explained below through several experimental and control groups.

[0066] The preparation methods of epoxidized soybean oil modified phenolic resin in all experimental and control groups are as follows:

[0067] Step 1: 25 parts of epoxidized soybean oil and 50 parts of phenol were reacted in a reactor at 120°C for 2 hours under the action of 0.3 parts of triethylamine. This allowed the epoxy groups of the epoxidized soybean oil to undergo a ring-opening addition reaction with the phenolic hydroxyl groups of the phenolic compound, yielding an intermediate containing phenolic ether bonds and secondary hydroxyl groups. The intermediate was then cooled to below 50°C, and 140 parts of formaldehyde aqueous solution (37% by mass), 20 parts of phenol, and 0.3 parts of ammonia were added. The mixture was then heated to 95°C to carry out a polycondensation reaction. Samples were taken every 30 minutes to test the gelation time (150°C) until the gelation time reached 150 seconds.

[0068] Step 2: Vacuum dehydration, controlling the vacuum degree ≥0.08MPa, until the gelation time reaches 110s at 150℃;

[0069] Step 3: Cool to below 70℃, add methyl ethyl ketone to adjust the solid content to 70%, discharge the material to obtain an epoxidized soybean oil modified phenolic resin solution.

[0070] Experimental group 1

[0071] (a) Preparation of resin composition.

[0072] 70 parts of epoxidized soybean oil modified phenolic resin (70% solid content), 25 parts of epoxy resin (100% solid content), 15 parts of aminotriazine modified phenolic resin (hydroxyl equivalent 130 g / eq, nitrogen content 15%), 5 parts of aluminum hydroxide, 15 parts of magnesium hydroxide, 8 parts of BDP, 0.6 parts of BYK-110 dispersant, 0.6 parts of KH-560 silane coupling agent, 0.3 parts of 2-methylimidazole accelerator, and 30 parts of propylene glycol methyl ether (PM) were dispersed in a high-speed disperser at 2000 r / min for 60 min, and the viscosity was adjusted to 100-150 mPa·s (25℃) to obtain a resin solution.

[0073] (ii) Preparation of CEM-3 copper clad laminate.

[0074] S1: Impregnate 7628 type electronic grade glass fiber cloth with the above resin solution, controlling the adhesive content of the cloth at 45-50%, and dry in an oven at 155℃-230℃ to remove the solvent, obtaining a glass cloth semi-cured sheet; use 85g / m 2 The glass fiber mat is impregnated with the above resin solution, and the resin content of the mat is controlled at 65-70%. It is then dried in an oven at 155-230℃ to remove the solvent, thus obtaining a glass mat semi-cured sheet.

[0075] S2: Take 4 glass mat semi-cured sheets as the core material, 2 glass cloth semi-cured sheets as the surface material, and cover them with 12-35μm electronic copper foil on the top and bottom to obtain the laminated material.

[0076] S3: Place the laminated material in a vacuum press and press it for 90 minutes at a temperature of 170℃ and a pressure of 5MPa to obtain CEM-3 copper clad laminate.

[0077] Experimental group 2

[0078] (a) Preparation of resin composition.

[0079] 85 parts of epoxidized soybean oil modified phenolic resin (70% solid content), 12 parts of epoxy resin (100% solid content), 10 parts of aminotriazine modified phenolic resin (hydroxyl equivalent 130 g / eq, nitrogen content 15%), 5 parts of aluminum hydroxide, 15 parts of magnesium hydroxide, 8 parts of BDP, 0.6 parts of BYK-110 dispersant, 0.6 parts of KH-560 silane coupling agent, 0.3 parts of 2-methylimidazole accelerator, and 30 parts of propylene glycol methyl ether (PM) were dispersed in a high-speed disperser at 2000 r / min for 60 min, and the viscosity was adjusted to 100-150 mPa·s (25℃) to obtain a resin solution.

[0080] (ii) Preparation of CEM-3 copper clad laminate.

[0081] S1: Impregnate 7628 type electronic grade glass fiber cloth with the above resin solution, controlling the adhesive content of the cloth at 45-50%, and dry in an oven at 155℃-230℃ to remove the solvent, obtaining a glass cloth semi-cured sheet; use 85g / m 2 The glass fiber mat is impregnated with the above resin solution, and the resin content of the mat is controlled at 65-70%. It is then dried in an oven at 155-230℃ to remove the solvent, thus obtaining a glass mat semi-cured sheet.

[0082] S2: Take 4 glass mat semi-cured sheets as the core material, 2 glass cloth semi-cured sheets as the surface material, and cover them with 12-35μm electronic copper foil on the top and bottom to obtain the laminated material.

[0083] S3: Place the laminated material in a vacuum press and press it for 90 minutes at a temperature of 170℃ and a pressure of 5MPa to obtain CEM-3 copper clad laminate.

[0084] Experimental group 3

[0085] (a) Preparation of resin composition.

[0086] 60 parts of epoxidized soybean oil modified phenolic resin (70% solid content), 20 parts of epoxy resin (100% solid content), 28 parts of aminotriazine modified phenolic resin (hydroxyl equivalent 130 g / eq, nitrogen content 15%), 5 parts of aluminum hydroxide, 15 parts of magnesium hydroxide, 8 parts of BDP, 0.6 parts of BYK-110 dispersant, 0.6 parts of KH-560 silane coupling agent, 0.3 parts of 2-methylimidazole accelerator, and 30 parts of propylene glycol methyl ether (PM) were dispersed in a high-speed disperser at 2000 r / min for 60 min, and the viscosity was adjusted to 100-150 mPa·s (25℃) to obtain a resin solution.

[0087] (ii) Preparation of CEM-3 copper clad laminate.

[0088] S1: Impregnate 7628 type electronic grade glass fiber cloth with the above resin solution, controlling the adhesive content of the cloth at 45-50%, and dry in an oven at 155℃-230℃ to remove the solvent, obtaining a glass cloth semi-cured sheet; use 85g / m 2 The glass fiber mat is impregnated with the above resin solution, and the resin content of the mat is controlled at 65-70%. It is then dried in an oven at 155-230℃ to remove the solvent, thus obtaining a glass mat semi-cured sheet.

[0089] S2: Take 4 glass mat semi-cured sheets as the core material, 2 glass cloth semi-cured sheets as the surface material, and cover them with 12-35μm electronic copper foil on the top and bottom to obtain the laminated material.

[0090] S3: Place the laminated material in a vacuum press and press it for 90 minutes at a temperature of 170℃ and a pressure of 5MPa to obtain CEM-3 copper clad laminate.

[0091] Comparison Group 1

[0092] (a) Preparation of resin composition.

[0093] 70 parts of ordinary thermosetting phenolic resin solution (70% solid content), 25 parts of epoxy resin (100% solid content), 15 parts of aminotriazine modified phenolic resin (hydroxyl equivalent 130 g / eq, nitrogen content 15%), 5 parts of aluminum hydroxide, 15 parts of magnesium hydroxide, 8 parts of BDP, 0.6 parts of BYK-110 dispersant, 0.6 parts of KH-560 silane coupling agent, 0.3 parts of 2-methylimidazole accelerator, and 30 parts of propylene glycol methyl ether (PM) were dispersed in a high-speed disperser at 2000 r / min for 60 min, and the viscosity was adjusted to 100-150 mPa·s (25℃) to obtain a resin solution.

[0094] (ii) Preparation of CEM-3 copper clad laminate.

[0095] S1: Impregnate 7628 type electronic grade glass fiber cloth with the above resin solution, controlling the adhesive content of the cloth at 45-50%, and dry in an oven at 155℃-230℃ to remove the solvent, obtaining a glass cloth semi-cured sheet; use 85g / m 2 The glass fiber mat is impregnated with the above resin solution, and the resin content of the mat is controlled at 65-70%. It is then dried in an oven at 155-230℃ to remove the solvent, thus obtaining a glass mat semi-cured sheet.

[0096] S2: Take 4 glass mat semi-cured sheets as the core material, 2 glass cloth semi-cured sheets as the surface material, and cover them with 12-35μm electronic copper foil on the top and bottom to obtain the laminated material.

[0097] S3: Place the laminated material in a vacuum press and press it for 90 minutes at a temperature of 170℃ and a pressure of 5MPa to obtain CEM-3 copper clad laminate.

[0098] Comparison Group 2

[0099] (a) Preparation of resin composition.

[0100] 70 parts of epoxidized soybean oil modified phenolic resin (70% solid content), 25 parts of epoxy resin (100% solid content), 5 parts of aluminum hydroxide, 15 parts of magnesium hydroxide, 8 parts of BDP, 0.6 parts of BYK-110 dispersant, 0.6 parts of KH-560 silane coupling agent, 0.3 parts of 2-methylimidazole accelerator, and 30 parts of propylene glycol methyl ether (PM) were dispersed in a high-speed disperser at 2000 r / min for 60 min, and the viscosity was adjusted to 100-150 mPa·s (25℃) to obtain the resin solution.

[0101] (ii) Preparation of CEM-3 copper clad laminate.

[0102] S1: Impregnate 7628 type electronic grade glass fiber cloth with the above resin solution, controlling the adhesive content of the cloth at 45-50%, and dry in an oven at 155℃-230℃ to remove the solvent, obtaining a glass cloth semi-cured sheet; use 85g / m 2 The glass fiber mat is impregnated with the above resin solution, and the resin content of the mat is controlled at 65-70%. It is then dried in an oven at 155-230℃ to remove the solvent, thus obtaining a glass mat semi-cured sheet.

[0103] S2: Take 4 glass mat semi-cured sheets as the core material, 2 glass cloth semi-cured sheets as the surface material, and cover them with 12-35μm electronic copper foil on the top and bottom to obtain the laminated material.

[0104] S3: Place the laminated material in a vacuum press and press it for 90 minutes at a temperature of 170℃ and a pressure of 5MPa to obtain CEM-3 copper clad laminate.

[0105] Comparison Group 3

[0106] (a) Preparation of resin composition.

[0107] 60 parts of ordinary bisphenol A type epoxy resin (epoxy equivalent 450-500), 3.5 parts of dicyandiamide curing agent, 30 parts of aluminum hydroxide, 0.2 parts of 2-methylimidazole accelerator, and 40 parts of propylene glycol methyl ether (PM) were dispersed in a high-speed disperser at 2500 r / min for 60 min, and the viscosity was adjusted to 100-150 mPa·s (25℃) to obtain the resin solution.

[0108] (ii) Preparation of CEM-3 copper clad laminate.

[0109] S1: Impregnate 7628 type electronic grade glass fiber cloth with the above resin solution, controlling the adhesive content of the cloth at 45-50%, and dry in an oven at 155℃-230℃ to remove the solvent, obtaining a glass cloth semi-cured sheet; use 85g / m 2 The glass fiber mat is impregnated with the above resin solution, and the resin content of the mat is controlled at 65-70%. It is then dried in an oven at 155-230℃ to remove the solvent, thus obtaining a glass mat semi-cured sheet.

[0110] S2: Take 4 glass mat semi-cured sheets as the core material, 2 glass cloth semi-cured sheets as the surface material, and cover them with 12-35μm electronic copper foil on the top and bottom to obtain the laminated material.

[0111] S3: Place the laminated material in a vacuum press and press it for 90 minutes at a temperature of 170℃ and a pressure of 5MPa to obtain CEM-3 copper clad laminate.

[0112] Comparison Group 4

[0113] (a) Preparation of resin composition.

[0114] 15 parts of epoxidized soybean oil modified epoxy resin (epoxy value 0.4), 75 parts of phosphorus modified phenolic epoxy resin, 18 parts of biphenyl phenolic resin, 30 parts of boehmite, 50 parts of silica, 40 parts of acetone, and 40 parts of ethylene glycol methyl ether were dispersed in a high-speed disperser at 2000 r / min for 60 min, and the viscosity was adjusted to 100-150 mPa·s (25℃) to obtain the resin solution.

[0115] (ii) Preparation of CEM-3 copper clad laminate.

[0116] S1: The fabric is made of 7628 type electronic grade glass fiber cloth impregnated with the above resin solution, and the glue content of the cloth is controlled at 45-50%. It is dried in an oven at 155℃-230℃ to remove the solvent, and a glass cloth semi-cured sheet is obtained. The core material is made of E glass fiber paper with different lengths of glass fiber ratio impregnated with the above resin solution, and the glue content of the felt is controlled at 65-70%. It is dried in an oven at 155-230℃ to remove the solvent, and an E glass fiber paper semi-cured sheet is obtained.

[0117] S2: Depending on the required board thickness, add several E-fiberglass paper prepregs between two glass cloth prepregs, and cover one or both sides of the glass cloth prepregs with copper foil. Hot-press forming (temperature 180℃, pressure 30kg / cm²). 2 The copper-clad laminate is obtained by heat preservation for 120 minutes and vacuum degree controlled at 1-10 kPa. Among them, the E glass fiber paper is composed of 17% short glass fibers with a length of 4 mm, 25% glass fibers with a length of 8 mm, and 58% glass fibers with a length of 9 mm or more.

[0118] Comparison Group 5

[0119] (a) Preparation of resin composition.

[0120] In a 1000 mL three-necked flask, 200 parts of phenol, 50 parts of epoxidized soybean oil, and 0.5 parts of amine catalyst were added sequentially and reacted at 80-90 °C for 60-90 min. Then, 200 parts of formaldehyde and 20 parts of nitrogen-containing phenolic resin were added and reacted at 80-90 °C for 70-90 min. The mixture was then dehydrated under reduced pressure. After complete dehydration, the mixture was heat-processed, and the gelation time was tested at 160 °C. The gelation time was controlled to be 75 seconds. Methanol was then added to obtain an epoxidized soybean oil modified phenolic resin solution with a solid content of 50%.

[0121] (ii) Preparation of CEM-3 copper clad laminate.

[0122] An attempt was made to use fiberglass mat instead of paper to prepare CEM-3 copper-clad laminates. However, due to the low resin solids content (50%), short gelation time (75s / 160℃, fast B-stage curing), and lack of epoxy resin to provide cross-linking bridging, the resin's wetting of the fiberglass mat was severely insufficient, resulting in large areas of missing adhesive on the mat PP and substandard quality of the prepreg. Forced hot-pressing of the laminates resulted in large-area delamination and bubbles, making it impossible to obtain structurally complete CEM-3 boards. Therefore, the performance data of the copper-clad laminate prepared using paper is listed in Table 1. Its heat resistance is 120 seconds, dimensional stability is 0.18 mm / m, and flame retardancy rating is only HB level, all of which are lower than the specifications of the CEM-3 copper-clad laminate of this invention.

[0123] Comparison Group 6

[0124] (a) Preparation of resin composition.

[0125] 70 parts of epoxidized soybean oil modified phenolic resin (70% solid content), 25 parts of epoxy resin (100% solid content), 15 parts of aminotriazine modified phenolic resin (hydroxyl equivalent 130 g / eq, nitrogen content 15%), 10 parts of aluminum hydroxide, 10 parts of magnesium hydroxide, 8 parts of BDP, 0.6 parts of BYK-110 dispersant, 0.6 parts of KH-560 silane coupling agent, 0.3 parts of 2-methylimidazole accelerator, and 30 parts of propylene glycol methyl ether (PM) were dispersed in a high-speed disperser at 2000 r / min for 60 min, and the viscosity was adjusted to 100-150 mPa·s (25℃) to obtain a resin solution.

[0126] (ii) Preparation of CEM-3 copper clad laminate.

[0127] S1: Impregnate 7628 type electronic grade glass fiber cloth with the above resin solution, controlling the adhesive content of the cloth at 45-50%, and dry in an oven at 155℃-230℃ to remove the solvent, obtaining a glass cloth semi-cured sheet; use 85g / m 2 The glass fiber mat is impregnated with the above resin solution, and the resin content of the mat is controlled at 65-70%. It is then dried in an oven at 155-230℃ to remove the solvent, thus obtaining a glass mat semi-cured sheet.

[0128] S2: Take 4 glass mat semi-cured sheets as the core material, 2 glass cloth semi-cured sheets as the surface material, and cover them with 12-35μm electronic copper foil on the top and bottom to obtain the laminated material.

[0129] S3: Place the laminated material in a vacuum press and press it for 90 minutes at a temperature of 170℃ and a pressure of 5MPa to obtain CEM-3 copper clad laminate.

[0130] Comparison Group 7

[0131] (a) Preparation of resin composition.

[0132] 70 parts of epoxidized soybean oil modified phenolic resin (70% solid content), 25 parts of epoxy resin (100% solid content), 15 parts of aminotriazine modified phenolic resin (hydroxyl equivalent 130 g / eq, nitrogen content 15%), 5 parts of aluminum hydroxide, 15 parts of magnesium hydroxide, 0.6 parts of BYK-110 dispersant, 0.6 parts of KH-560 silane coupling agent, 0.3 parts of 2-methylimidazole accelerator, and 30 parts of propylene glycol methyl ether (PM) were dispersed in a high-speed disperser at 2000 r / min for 60 min, and the viscosity was adjusted to 100-150 mPa·s (25℃) to obtain a resin solution.

[0133] (ii) Preparation of CEM-3 copper clad laminate.

[0134] S1: Impregnate 7628 type electronic grade glass fiber cloth with the above resin solution, controlling the adhesive content of the cloth at 45-50%, and dry in an oven at 155℃-230℃ to remove the solvent, obtaining a glass cloth semi-cured sheet; use 85g / m 2 The glass fiber mat is impregnated with the above resin solution, and the resin content of the mat is controlled at 65-70%. It is then dried in an oven at 155-230℃ to remove the solvent, thus obtaining a glass mat semi-cured sheet.

[0135] S2: Take 4 glass mat semi-cured sheets as the core material, 2 glass cloth semi-cured sheets as the surface material, and cover them with 12-35μm electronic copper foil on the top and bottom to obtain the laminated material.

[0136] S3: Place the laminated material in a vacuum press and press it for 90 minutes at a temperature of 170℃ and a pressure of 5MPa to obtain CEM-3 copper clad laminate.

[0137] The performance of the copper-clad laminates prepared in each experimental group and the control group was tested using the following methods:

[0138] Test Project Test standards / methods Heat resistance (290℃ floating weld) The sample was floated on the surface of a 290°C tin furnace, and the time when bubbling and delamination occurred was recorded. Dimensional stability IPC-TM-650 2.2.4, testing dimensional changes after etching. Flame retardancy UL94 Vertical Burning Test Glass transition temperature (Tg) IPC-TM-650 2.4.25, DSC method Coefficient of thermal expansion (CTE, α1) IPC-TM-650 2.4.24, TMA method, tests α1 (50-260℃ range), reflecting the dimensional stability of the board material during heating; the lower the value, the smaller the dimensional change at high temperature. Dielectric constant (Dk) IPC-TM-650 2.5.5.9, tested at 1MHz, reflects the impact of the board material on signal transmission. The lower and more stable the value, the better the high-frequency performance. Bending strength (longitudinal) IPC-TM-650 2.2.4 Peel strength (125℃) IPC-TM-650 2.4.8 (12-35μm copper foil) Water absorption rate IPC-TM-650 2.6.2.1 (E-24 / 50+D-24 / 23)

[0139] Table 1. Performance Comparison of CEM-3 Copper Clad Laminates in Different Experimental Groups

[0140] Test Project Experimental group 1 Experimental group 2 Experimental group 3 Industry standard Application substrate CEM-3 CEM-3 CEM-3 - Heat resistance (290℃ / s) 335 290 345 260℃ / 10 seconds or 260℃ / >120 seconds Dimensional stability (mm / m) 0.06 0.10 0.07 ≤0.15 Flame retardancy (UL94) V-0 V-0 V-0 V-0 Tg(℃, DSC) 187 169 193 140-160 CTE (α1, ppm / ℃, 50-260℃) 28 32 26 30-45 Dielectric constant (1MHz) 4.6 4.5 4.8 4.2-5.0 Flexural strength (MPa, longitudinal) 425 395 440 355-430 Peel strength (N / mm, 125℃) 1.78 1.85 1.72 ≥1.6 Water absorption rate (%) 0.07 0.09 0.08 0.06-0.20 cost lower Low medium -

[0141] Table 2 Performance Comparison of CEM-3 Copper Clad Laminates in Different Comparison Groups

[0142] Test Project Comparison Group 1 Comparison Group 2 Comparison Group 3 Comparison Group 4 Comparison Group 5 Comparison Group 6 Comparison Group 7 Application substrate CEM-3 CEM-3 CEM-3 CEM-3 Paper base CEM-3 CEM-3 Heat resistance 245 228 15 255 120 266 313 Dimensional stability 0.14 0.11 0.22 0.13 0.18 0.09 0.12 Flame retardancy V-0 V-1 V-0 V-0 HB V-0 V-1 Tg 165 158 135 172 142 178 182 CTE 35 39 42 34 46 30 33 Dielectric constant 4.9 4.6 4.4 4.7 4.8 4.7 4.5 flexural strength 445 410 380 405 370 415 420 Peel strength 1.68 1.80 1.58 1.65 1.6 1.75 1.76 Water absorption rate 0.11 0.09 0.15 0.10 0.12 0.08 0.10 cost medium lower Low high Low lower Low

[0143] (Note: Comparison group 5 uses paper-based copper-clad laminates; the data is for reference only.)

[0144] According to Tables 1 and 2, we can see that:

[0145] 1. Comparison between Experimental Group 1 and Control Groups 1 and 2 shows that all three components—epoxidized soybean oil-modified phenolic resin, epoxy resin, and aminotriazine-modified phenolic resin—are indispensable. Epoxidized soybean oil-modified phenolic resin provides flexibility and a low coefficient of thermal expansion; epoxy resin provides crosslinking bridging, high crosslinking density, and rigid crosslinking nodes; and aminotriazine-modified phenolic resin provides rigid crosslinking nodes and contributes to nitrogen-containing flame retardancy. The combination of these three components enables the cured network to possess high rigidity, moderate flexibility, and excellent thermal stability.

[0146] 2. Comparison between Experimental Group 1 and Control Group 7 shows that the N / P / Mg / Al quaternary flame retardant cannot achieve V-0 rating without phosphorus. Comparison between Experimental Group 1 and Control Group 6 shows that the ratio of magnesium hydroxide to aluminum hydroxide needs to be within an optimal range to obtain the best gradient flame retardant and heat resistance effects.

[0147] 3. When the paper-based formulation of control group 5 was used on CEM-3 substrate, significant problems of poor wetting, insufficient adhesive, and bubbles occurred, making it impossible to obtain qualified boards. Experimental group 1, by optimizing the wettability of the resin composition and using specific process parameters for 7628 type fiberglass cloth (45-50% adhesive content) and 85g / m² fiberglass mat (65-70% adhesive content), successfully prepared high-performance CEM-3 copper-clad laminates.

[0148] 4. Performance comparison of experimental groups 1-3 shows that increasing the content of epoxidized soybean oil-modified phenolic resin is beneficial for improving peel strength and reducing dielectric constant, but it will reduce Tg and flexural strength; increasing the content of benzoguanamine-modified phenolic resin is beneficial for improving Tg and flexural strength, but it will increase dielectric constant. The formulation ratio of experimental group 1 achieves the best balance of various properties, taking into account the comprehensive requirements of heat resistance (335s), dimensional stability (0.06 mm / m), high Tg (187℃), V-0 flame retardancy, and lower cost.

[0149] 5. Compared with the traditional epoxy / dicyandiamide system (comparative group 3), experimental group 1 exhibits over 20 times improved heat resistance, a 52°C increase in Tg, a 33% reduction in the coefficient of thermal expansion, and a 73% improvement in dimensional stability. Compared with comparative group 4, experimental group 1 demonstrates significant advantages in heat resistance, Tg, dimensional stability, and peel strength, while also having lower raw material costs. Compared with comparative group 5, this invention successfully expands the application field of epoxy soybean oil modified phenolic resin from paper-based copper-clad laminates to CEM-3 copper-clad laminates, while simultaneously achieving a leapfrog upgrade from non-flame retardant to V-0 flame retardant.

[0150] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An epoxy soybean oil-modified phenolic resin composition for CEM-3 copper clad laminates, characterized in that: By weight, it consists of the following components: 60-85 parts of epoxidized soybean oil modified phenolic resin solution, 10-50 parts epoxy resin 5-35 parts aminotriazine modified phenolic resin, 20-60 parts of inorganic flame retardant filler 4-15 parts phosphorus-based flame retardant 1.1-3 parts of adjuvants, 30 parts of the first solvent; The epoxidized soybean oil modified phenolic resin is a reactive modified phenolic resin obtained by reacting epoxidized soybean oil with phenolic compounds in a ring-opening reaction, followed by a polycondensation reaction with formaldehyde. The epoxy resin is a mixture of phenolic epoxy resin and bisphenol A type epoxy resin; The aminotriazine-modified phenolic resin is a solid resin obtained by condensation reaction of one or two of benzoguanidine and acetylguanidine with phenolic resin. The inorganic flame-retardant filler is a compound of magnesium hydroxide and aluminum hydroxide.

2. The epoxy soybean oil-modified phenolic resin composition for CEM-3 copper clad laminates according to claim 1, characterized in that: The epoxy soybean oil modified phenolic resin solution has a solid content of 68-72% and an epoxy equivalent of 400-500 g / eq; the epoxy soybean oil modified phenolic resin is prepared through the following steps: Step 1: 20-30 parts by weight of epoxidized soybean oil and 40-60 parts by weight of phenolic compounds are reacted at 100-140℃ for 1-3 hours under the action of 0.1-0.5 parts by weight of the first catalyst, so that the epoxy group of epoxidized soybean oil and the phenolic hydroxyl group of phenolic compound undergo a ring-opening addition reaction to obtain an intermediate containing phenolic ether bond and secondary hydroxyl group. Step 2: Cool the intermediate to below 50°C, add 120-160 parts by weight of formaldehyde aqueous solution, 10-30 parts by weight of phenolic compound and 0.1-0.5 parts by weight of second catalyst, heat to 90-100°C to carry out polycondensation reaction until the gelation time reaches 140-160s at 150°C. Step 3: Vacuum dehydration until the gelation time reaches 100-120 seconds at 150℃; Step 4: Cool to below 70°C, add a second solvent to adjust the solid content to 68-72%.

3. The epoxy soybean oil modified phenolic resin composition for CEM-3 copper clad laminate according to claim 2, characterized in that: The phenolic compound is one or more of phenol, bisphenol A, alkyl-substituted phenol, and cashew phenol; the first catalyst is one or two of triethylamine and triethanolamine; the second catalyst is one or two of ammonia and ethylenediamine; and the second solvent is one or two of methyl ethyl ketone and acetone.

4. The epoxy soybean oil modified phenolic resin composition for CEM-3 copper clad laminate according to claim 1, characterized in that: The bisphenol A type epoxy resin is bisphenol A type epoxy resin E-51, and the mass ratio of the phenolic epoxy resin to the bisphenol A type epoxy resin E-51 is 4:1, with a solid content of 100%.

5. The epoxy soybean oil modified phenolic resin composition for CEM-3 copper clad laminate according to claim 1, characterized in that: The aminotriazine-modified phenolic resin has a hydroxyl equivalent of 120-140 g / eq, a nitrogen content of 12-18%, and a softening point of 100-130℃.

6. The epoxy soybean oil modified phenolic resin composition for CEM-3 copper clad laminate according to claim 1, characterized in that: In the inorganic flame retardant filler, the mass ratio of aluminum hydroxide to magnesium hydroxide is 1:(2-3.5).

7. The epoxy soybean oil modified phenolic resin composition for CEM-3 copper clad laminate according to claim 1, characterized in that: The phosphorus-based flame retardant is one or more of triphenyl phosphate, bisphenol A-bis(diphenyl phosphate), resorcinol-bis(diphenyl phosphate), and resorcinol-bis[bis(2,6-dimethylphenyl) phosphate].

8. The epoxy soybean oil modified phenolic resin composition for CEM-3 copper clad laminate according to claim 1, characterized in that: The first solvent is one or both of propylene glycol methyl ether and propylene glycol monomethyl ether acetate.

9. The epoxy soybean oil modified phenolic resin composition for CEM-3 copper clad laminate according to claim 1, characterized in that: The adjuvant contains 0.5-1.0 parts of dispersant, 0.5-1.0 parts of silane coupling agent, and 0.1-0.5 parts of 2-methylimidazole accelerator.

10. The epoxy soybean oil modified phenolic resin composition for CEM-3 copper clad laminates according to claim 1, characterized in that: The preparation method is as follows: Epoxidized soybean oil modified phenolic resin, epoxy resin, aminotriazine modified phenolic resin, inorganic flame retardant filler, phosphorus flame retardant, additives, and first solvent are dispersed in a high-speed disperser at a speed of 1000-3000 r / min for 40-80 min. Under the condition of 25℃, the viscosity is adjusted to 80-200 mPa·s to obtain resin solution.

11. A CEM-3 copper clad laminate, characterized in that: Its insulation layer comprises a cured layer obtained by impregnating a reinforcing material with the resin composition of any one of claims 1-10 and hot pressing it, wherein the reinforcing material comprises a core reinforcing material and a surface reinforcing material, wherein the core reinforcing material is 75-105 g / m² glass fiber mat and the surface reinforcing material is 7628-7638 type electronic grade glass fiber cloth.

12. The CEM-3 copper-clad laminate according to claim 11, characterized in that: The preparation method of the CEM-3 copper clad laminate includes the following steps: S1: Impregnate electronic-grade glass fiber cloth with the resin composition, controlling the adhesive content of the cloth to be 45-50%; impregnate glass fiber mat with the resin composition, controlling the adhesive content of the mat to be 65-70%; dry the impregnated electronic-grade glass fiber cloth and glass fiber mat in an oven at 155-230℃ to obtain glass cloth semi-cured sheet and glass mat semi-cured sheet. S2: Stack 1-4 glass mat prepreg sheets with 2 glass cloth prepreg sheets, and cover the top and bottom with 12-35μm electronic copper foil to obtain the laminated material; S3: The laminated materials are hot-pressed in a vacuum hot press at 160-180℃ and 4-6MPa for 85-100 minutes to obtain CEM-3 copper clad laminate.