Benzocyclobutenyl-terminated active ester resin as well as preparation method and application thereof

Abstract

The invention relates to the technical field of active resin, in particular to benzocyclobutenyl-terminated active ester resin as well as a preparation method and application thereof. The preparation method of the benzocyclobutenyl-terminated active ester resin comprises the following steps: stirring and mixing an acyl chloride-containing compound, diallyl bisphenol A, a benzocyclobutenyl end-capping reagent and a first organic solvent to obtain a first mixture; dropwise adding an acid-binding agent into the first mixture, and carrying out polymerization reaction to obtain a reaction product; and purifying the reaction product, and removing the first organic solvent to obtain the benzocyclobutenyl-terminated active ester resin. According to the preparation method, through the synergistic effect of flexible chain segment embedding, terminal group polarity adjustment, main chain polarity optimization and molecular weight control, the intermolecular acting force of BMI containing the BCB terminal group is effectively reduced, the compatibility of BMI molecules containing the BCB terminal group and an organic solvent is improved, and therefore the solubility of the BMI molecules is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of active resin, in particular to a benzocyclobutene-terminated active ester resin and a preparation method and application thereof. BACKGROUND

[0002] Printed circuit board (PCB) is widely used in the fields of microwave communication, aerospace, medical equipment, industrial control, etc. PCB is an important component of electronic communication, and the performance of PCB mainly depends on the performance of copper-clad plate. With the rapid development of high-frequency and high-speed communication field, higher requirements for the performance of copper-clad plate are put forward in the communication field. In the copper-clad plate, the base resin is the main raw material and has an important influence on the performance of the copper-clad plate. Benzocyclobutene (BCB) is a full carbon-hydrogen structure monomer, which has low polarity, and the polymer containing BCB group has excellent dielectric properties after curing. At the same time, BCB monomer has high reactivity, which makes BCB monomer generate o-xylene intermediate at 200℃ or above. In addition, BCB monomer can occur chain extension or crosslinking reaction through cycloaddition or linear addition polymerization, and also can form benzohexacyclic ring structure by Diels-Alder addition reaction with other dienophiles. In the Diels-Alder addition reaction process, no additional catalyst or initiator is needed, and no by-products or small molecules are produced. Therefore, the polymer containing BCB group has good dielectric properties and thermal stability, and is considered as a new generation of high-performance low-dielectric material.

[0003] Bismaleimide resin (BMI) has good thermal stability, dielectric property, corrosion resistance and other advantages, and the molding process of BMI is simple. In the curing process of BMI, no small molecule substances are released, so BMI is one of the most competitive resin types of high-performance copper-clad plate substrate materials. If BMI is combined with the polymer containing BCB group to form a BMI cured product containing BCB end group, the BMI cured product can have good thermal stability, glass transition temperature (Tg) and low dielectric constant (Dk). However, the rigidity of the molecular chain and the interaction between or within the chains in the BMI cured product will affect the solubility of the BMI cured product in the solvent, which greatly limits the application of the BMI cured product. SUMMARY

[0004] The present application provides a benzocyclobutene-terminated active ester resin and a preparation method and application thereof, to solve the technical problem of how to improve the solubility of BMI containing BCB end group.

[0005] In a first aspect, the present application provides a preparation method of a benzocyclobutene-terminated active ester resin, which comprises: stirring and mixing an acyl chloride compound, a diallyl bisphenol A, a benzocyclobutenyl capping agent and a first organic solvent to obtain a first mixture; adding a deacidifying agent dropwise into the first mixture and performing a polymerization reaction to obtain a reaction product; purifying the reaction product and removing the first organic solvent to obtain a benzocyclobutenyl-capped active ester resin.

[0006] Optionally, the amount of substance n1 of the acyl chloride compound, the amount of substance n2 of the diallyl bisphenol A and the amount of substance n3 of the benzocyclobutenyl capping agent satisfy: n1:n2:n3=1:(0.50 to 0.91):(0.18 to 1.00).

[0007] Optionally, the deacidifying agent includes any one of triethylamine, trimethylamine, pyridine, sodium carbonate, potassium carbonate and potassium hydroxide; the amount of substance n4 of the deacidifying agent and the amount of substance n1 of the acyl chloride compound in the first mixture satisfy: n4:n1=(2.03 to 2.05):1.

[0008] Optionally, the first organic solvent includes at least two of toluene, xylene, butanone, methyl isobutyl ketone and dimethylformamide; and / or The acyl chloride compound includes at least one of 2,2'-biphenyl dicarboxylic acid chloride, 4,4'-biphenyl dicarboxylic acid chloride, isophthaloyl chloride, terephthaloyl chloride and phthaloyl chloride.

[0009] Optionally, the temperature of the polymerization reaction is 50°C to 80°C, and the time of the polymerization reaction is 1h to 4h.

[0010] In a second aspect, the embodiments of the present application provide a benzocyclobutenyl-capped active ester resin, which is obtained by the preparation method in the first aspect; the active ester resin has a molecular structure as shown in formula 1, Formula 1, In formula 1, R includes , , , and at least one of them; the value of n is 1 to 10.

[0011] In a third aspect, the embodiments of the present application provide a copper-clad plate, which includes the active ester resin in the second aspect.

[0012] In a fourth aspect, the embodiments of the present application provide a preparation method of a copper-clad plate, which includes: The active ester resin, the resin matrix, the filler, the promoter and the second solvent in the second aspect are mixed to obtain a prepreg with a preset solid content; wherein the resin matrix is a bismaleimide resin or an epoxy resin; and the preset solid content is 60% to 70%; The glass fiber cloth is impregnated using the prepreg with the preset solid content to obtain an impregnated glass fiber cloth; The impregnated glass fiber cloth is baked to obtain a prepreg; The prepreg is laminated to obtain a laminate; The copper foil is covered on both sides of the laminate, and vacuum hot pressing is performed to obtain a copper-clad plate.

[0013] Optionally, in the case where the resin matrix is a bismaleimide resin, the mass m1 of the active ester resin, the mass m2 of the resin matrix, the mass m3 of the filler and the mass m4 of the promoter satisfy: m1:m2:m3:m4=(33 to 45):100:(35 to 65):(0.3 to 0.6); and / or In the case where the resin matrix is an epoxy resin, the mass m1 of the active ester resin, the mass m2 of the resin matrix, the mass m3 of the filler and the mass m4 of the promoter satisfy: m1:m2:m3:m4=(50 to 70):100:(40 to 70):(0.2 to 0.5).

[0014] Optionally, the bismaleimide resin includes at least one of bis(3-ethyl-5-methyl-4-maleimide phenyl) methane, bis(3,5-diethyl-4-maleimide phenyl) methane, bis(4-maleimide phenyl) methane, bis(3,5-dimethyl-4-maleimide phenyl) methane, 2,2'-bis[4-(4-maleimide phenoxy) phenyl] propane, diphenyl methane bismaleimide and 2,2'-N,N'-m-phenylene bismaleimide; and / or The epoxy resin includes at least one of dicyclopentadiene phenol epoxy resin, bisphenol A formaldehyde novolac epoxy resin, phenol formaldehyde novolac epoxy resin and o-cresol novolac epoxy resin; and / or The promoter includes at least one of 2,4,6-tris(dimethylaminomethyl) phenol, triphenylphosphine, 4-dimethylaminopyridine, 2-methylimidazole and 1-benzyl-2-methylimidazole; and / or The filler includes at least one of silicon dioxide, montmorillonite, magnesium oxide, aluminum trioxide and mica powder; and / or The second organic solvent includes at least one of acetone, butanone, methyl isobutyl ketone, toluene, propylene glycol monomethyl ether and ethylene glycol methyl ether.

[0015] The above technical solution provided by the embodiments of the present application has the following advantages compared with the prior art. The preparation method of the benzocyclobutene end-capped active ester resin provided by the embodiments of the present application uses diallyl bisphenol A as a monomer, can introduce flexible chain segments in benzocyclobutene, which can reduce the molecular crystallization tendency of the bismaleimide resin and improve the dispersion capacity of the bismaleimide resin in an organic solvent; in addition, the introduction of a benzocyclobutene end-capping agent can reduce the hydrogen bonding or polar attraction between the end groups of the benzocyclobutene end-capped active ester resin, and improve the solubility of the bismaleimide resin in a non-polar or medium-polar solvent; in addition, the introduction of an acyl chloride-containing compound in the preparation method can form an active ester resin main chain through the polymerization reaction of the acyl chloride-containing compound and diallyl bisphenol A, which can enhance the compatibility of the ester resin main chain with the organic solvent and adjust the solubility of the bismaleimide resin molecule; in addition, the slow addition of the acid-binding agent can gently control the polymerization reaction rate, reduce the dissolution resistance caused by the entanglement between the bismaleimide resin molecules, and further improve the solubility. BRIEF DESCRIPTION OF DRAWINGS

[0016] The accompanying drawings, which are incorporated into and form a part of the specification, illustrate preferred embodiments of the present application and, together with the description, serve to explain the principles of the application.

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the accompanying drawings needed to be used in the embodiments or the prior art description will be briefly introduced. Obviously, for those skilled in the art, other drawings can also be obtained without creative labor based on these drawings.

[0018] Figure 1 The preparation method of the benzocyclobutene end-capped active ester resin provided by the embodiments of the present application has a preparation method flowchart. Figure 2 The preparation method of the copper-clad plate provided by the embodiments of the present application has a preparation method flowchart. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solutions and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0020] The range descriptions described in the present application, such as numerical range, ratio range and the like, include all possible sub-ranges and single values within the range, for example, the range description of "1 to 6" or "1~6" covers all sub-ranges (such as 1 to 3, 2 to 5, etc.) and single numbers (such as 1, 2, 3, 4, 5, 6) between 1 and 6. Unless otherwise specified, the terms "comprise", etc. used herein mean "include but not limited to"; the relationship terms "first", "second", etc. are only used to distinguish different entities or operations, and do not imply actual sequence or relationship; "and / or" means that multiple cases can exist alone or simultaneously; "at least one", "multiple", "at least one" and the like refer to any combination of the corresponding objects, including single or multiple combinations. The proportional relationship involved in the present application, such as mass ratio, molar ratio and the like, should be understood as the corresponding relationship between the front and the back of the ratio according to the description order. The raw materials, reagents, instruments and equipment used in the present application can be purchased or prepared by existing methods.

[0021] Figure 1 An exemplary flow chart of a preparation method of a benzocyclobutene-terminated active ester resin provided by the embodiments of the present application is shown. As Figure 1 shown, the preparation method of a benzocyclobutene-terminated active ester resin provided by the embodiments of the present application comprises: S1. Stirring and mixing an acyl chloride compound, a diallyl bisphenol A, a benzocyclobutene-terminated agent and a first organic solvent to obtain a first mixture; S2. Adding an acid-binding agent dropwise into the first mixture and performing a polymerization reaction to obtain a reaction product; S3. Purifying the reaction product, removing the first organic solvent, and obtaining a benzocyclobutene-terminated active ester resin.

[0022] It should be noted that the stirring and mixing can be carried out in a four-necked reactor equipped with nitrogen, stirring, reflux condenser.

[0023] It should be noted that the purification can be filtration, water washing and reduced pressure distillation. The target pH value of the water washing can be 7.

[0024] It should be noted that the dropping time can be 1h to 3h, and after the dropping is completed, the temperature is raised to the required temperature for the polymerization reaction.

[0025] It should be noted that the preparation method of a benzocyclobutene-terminated active ester resin provided by the embodiments of the present application reduces the intermolecular force and improves the polarity matching by molecular structure design and reaction control, so as to improve the solubility of the BCB end group-containing BMI. The specific mechanism is as follows: 1. Introducing flexible segments to reduce molecular rigidity and packing density: This preparation method uses diallyl bisphenol A as a monomer, which contains an allyl group (-CH2-CH=CH2) in its molecular structure. This flexible segment can be embedded in the main chain of the resin molecule through polymerization, breaking the dense packing of the rigid aromatic ring (such as benzene ring, imide ring) in the BMI molecule, reducing the van der Waals force and π-π stacking interaction between molecules, thereby reducing the crystallization tendency of the BMI molecule (rigid molecules tend to crystallize, and the higher the crystallinity, the lower the solubility), and improving the dispersion ability of the BMI molecule in organic solvents.

[0026] 2. Structural adjustment of BCB end groups: The introduction of BCB end-capping agent (benzocyclobutene group) replaces the strong polarity or high reactivity end groups (such as imide group, hydroxyl group, etc.) that may exist in the BMI molecule through end-capping reaction. The BCB group itself has moderate polarity and small steric hindrance, which can reduce the hydrogen bonding or polarity attraction between end groups, avoid the formation of aggregates due to the interaction between BMI molecules, and thus improve the solubility of BMI molecules in non-polar or moderately polar solvents.

[0027] 3. Polar matching optimization of active ester structure: This preparation method forms an active ester resin main chain by polymerization of an acyl chloride compound and diallyl bisphenol A, and the polarity of the ester group (-COO-) is between that of the imide group (-CO-N-CO-) and the alkyl group, which is more easily matched with common organic solvents (such as ketones, ethers), thereby enhancing the compatibility of the ester resin main chain with organic solvents. Compared with the strong polar and rigid structure of pure BMI molecules, the polarity adjustment of active ester can significantly improve the solubility of BMI molecules.

[0028] 4. Controllability of molecular weight and distribution: The dropwise addition of the acid binding agent (stepwise neutralization of the acid generated by the reaction, such as HCl) can gently control the polymerization reaction rate, avoiding excessive molecular weight or wide distribution caused by vigorous reaction. Moderate molecular weight (avoiding entanglement caused by too long molecular chains) and narrow distribution help to reduce the dissolution resistance caused by molecular entanglement, further improving the solubility.

[0029] In summary, the preparation method of the benzocyclobutene end-capped active ester resin provided by the embodiments of the present application effectively reduces the interaction between BMI molecules containing BCB end groups, improves the compatibility of BMI molecules containing BCB end groups with organic solvents, and thus improves the solubility of BMI molecules.

[0030] In some alternative embodiments, the molar amount n1 of the acyl chloride compound, the molar amount n2 of the diallyl bisphenol A, and the molar amount n3 of the benzo-cyclobutene capping agent satisfy: n1:n2:n3=1:(0.50 to 0.91):(0.18 to 1.00).

[0031] In these embodiments, the molar ratio of 1:(0.50 to 0.91):(0.18 to 1.00) among the acyl chloride compound, the diallyl bisphenol A, and the benzo-cyclobutene capping agent can cooperatively adjust the intermolecular force, the polarity distribution, and the molecular weight of the benzo-cyclobutene-capped active ester resin through a polymerization reaction, thereby improving the intermolecular force of the BCB-end-group-containing BMI molecule and increasing the solubility of the BMI molecule.

[0032] The molar amount n2 of the diallyl bisphenol A can be 0.50, 0.55, 0.60, 0.65, 0.70, 0.75, 0.80, 0.85, 0.90, or 0.91.

[0033] In some alternative embodiments, the acid-binding agent includes any one of triethylamine, trimethylamine, pyridine, sodium carbonate, potassium carbonate, and potassium hydroxide; and the molar amount n4 of the acid-binding agent and the molar amount n1 of the acyl chloride compound in the first mixture satisfy: n4:n1=(2.03 to 2.05):1.

[0034] In these embodiments, the use of the acid-binding agent including any one of triethylamine, trimethylamine, pyridine, sodium carbonate, potassium carbonate, and potassium hydroxide, and the molar ratio of (2.03 to 2.05):1 of the acid-binding agent and the acyl chloride compound in the first mixture can gently control the polymerization rate through the acid-binding agent, avoid excessive molecular weight or too wide distribution caused by violent reaction, and help to reduce the solubility resistance caused by intermolecular entanglement, thereby further increasing the solubility of the BMI molecule.

[0035] The molar amount n4 of the acid-binding agent can be 2.030, 2.035, 2.040, 2.045, or 2.050.

[0036] In some alternative embodiments, the first organic solvent includes at least two of toluene, xylene, butanone, methyl isobutyl ketone, and dimethylformamide; and / or The acyl chloride compound includes at least one of 2,2'-biphenyl dicarboxylic acid chloride, 4,4'-biphenyl dicarboxylic acid chloride, isophthaloyl chloride, terephthaloyl chloride, and phthaloyl chloride.

[0037] In these embodiments, the use of the first organic solvent comprising at least two of toluene, xylene, butanone, methyl isobutyl ketone and dimethylformamide can facilitate the uniform dispersion of the acyl chloride-containing compound, the diallyl bisphenol A and the benzocyclobutene capping agent, and facilitate the subsequent acid binding agent dropwise addition stage of the polymerization reaction to proceed sufficiently to form the benzocyclobutene-capped active ester resin. In addition, the use of the first organic solvent comprising at least two of toluene, xylene, butanone, methyl isobutyl ketone and dimethylformamide can facilitate the uniform dispersion of the acyl chloride-containing compound, the diallyl bisphenol A and the benzocyclobutene capping agent, and facilitate the subsequent acid binding agent dropwise addition stage of the polymerization reaction to proceed sufficiently to form the benzocyclobutene-capped active ester resin. In some alternative embodiments, the temperature of the polymerization reaction is 50°C to 80°C, and the time of the polymerization reaction is 1h to 4h.

[0038] In these embodiments, the temperature of 50°C to 80°C and the time of 1h to 4h of the polymerization reaction can facilitate the sufficient proceeding between the acyl chloride-containing compound, the diallyl bisphenol A and the benzocyclobutene capping agent to form the benzocyclobutene-capped active ester resin.

[0039] The temperature of the polymerization reaction can be 50°C, 55°C, 60°C, 65°C, 70°C, 75°C or 80°C.

[0040] The time of the polymerization reaction can be 1h, 1.5h, 2.0h, 2.5h, 3.0h, 3.5h or 4.0h.

[0041] Based on one general inventive concept, the embodiments of the present application provide a benzocyclobutene-capped active ester resin, which is obtained by the preparation method; the active ester resin has a molecular structure as shown in Formula 1, Formula 1, In Formula 1, R comprises , , , and at least one; n has a value of 1 to 10.

[0042] The active ester resin is obtained based on the above preparation method, and the specific steps of the preparation method can refer to the above embodiments. Since the active ester resin adopts part or all of the technical solutions of the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be repeated here.

[0043] It should be noted that the active ester resin is introduced with the BCB structure, the BCB structure gives the active ester resin cured product good dielectric properties, the active ester resin can occur Diels-Alder addition reaction with allyl and BMI at high temperature, form a benzohexa ring structure, the benzohexa ring structure can further improve the thermal stability of BMI, and no by-products or small molecules are produced in the Diels-Alder addition reaction process, which can effectively reduce the delamination and explosion of the substrate of the copper-clad plate during lamination or tin soldering. At the same time, the Diels-Alder addition reaction can introduce the allyl structure into the BMI, which not only overcomes the problem of large brittleness and difficult processing of the BMI cured product, but also increases the solubility of the BMI, so that the BMI is suitable for various scenes. In addition, there is no polar hydroxyl group in the structure of the BMI system, so that the BMI cured product has good dielectric properties, overcoming the problem of dielectric property decline caused by bismaleimide toughening modification.

[0044] Based on one overall inventive concept, the embodiments of the present application provide a copper-clad plate, which comprises the active ester resin.

[0045] The copper-clad plate is realized based on the active ester resin described above, and the specific composition of the active ester resin can refer to the embodiments described above. Since the copper-clad plate adopts part or all of the technical solutions of the embodiments described above, it at least has all the beneficial effects brought by the technical solutions of the embodiments described above, which will not be repeated here.

[0046] Figure 2 An exemplary flow chart of a preparation method of a copper-clad plate provided by the embodiments of the present application is shown; Based on one overall inventive concept, as Figure 2 shown, the embodiments of the present application provide a preparation method of a copper-clad plate, which comprises: S1. Mixing the active ester resin, a resin matrix, a filler, a promoter and a second solvent to obtain a prepreg with a preset solid content; wherein the resin matrix is a bismaleimide resin or an epoxy resin; and the preset solid content is 60% to 70%; S2. Using the prepreg with a preset solid content to impregnate a glass fiber cloth to obtain an impregnated glass fiber cloth; S3. Baking the impregnated glass fiber cloth to obtain a semi-cured sheet; S4. Laminating the semi-cured sheet to obtain a laminated body; S5. Covering copper foils on both sides of the laminated body and performing vacuum hot pressing to obtain a copper-clad plate.

[0047] This preparation method refers to the preparation method of the copper-clad laminate described above. The specific composition of the copper-clad laminate can be referred to in the above embodiments. Since this preparation method adopts some or all of the technical solutions of the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be elaborated here.

[0048] It should be noted that the number of prepreg sheets used in this lamination process can be from 3 to 15.

[0049] It should be noted that the specific operation of this vacuum hot pressing varies depending on the resin matrix. When the resin matrix is ​​bismaleimide resin, the specific operation of this vacuum hot pressing includes: first, heating the laminate from room temperature to 200°C at a heating rate of 3°C / min, while simultaneously increasing the pressure from 0.2MPa to 4MPa at a rate of 0.1MPa / min, and evacuating the laminate and copper foil to within 80 torr, and maintaining the pressure for 1 to 2 hours to obtain the pressed body; then heating the pressed body to 210°C to 240°C, and maintaining it under constant pressure (4MPa) for 3 to 6 hours. When the resin matrix is ​​epoxy resin, the specific operation of the vacuum hot pressing includes: first, heating the laminate from room temperature to 180°C at a heating rate of 3°C / min, while simultaneously increasing the pressure from 0.2MPa to 4MPa at a rate of 0.1MPa / min, and evacuating the laminate and copper foil to within 80 torr, and maintaining the press under pressure for 1 to 2 hours to obtain the pressed body; then heating the pressed body to 200°C to 230°C, and maintaining it under constant pressure (4MPa) for 3 to 5 hours.

[0050] In some alternative embodiments, when the resin matrix is ​​a bismaleimide resin, the mass m1 of the active ester resin, the mass m2 of the resin matrix, the mass m3 of the filler, and the mass m4 of the accelerator satisfy: m1:m2:m3:m4 = (33 to 45):100:(35 to 65):(0.3 to 0.6); and / or When the resin matrix is ​​epoxy resin, the mass m1 of the active ester resin, the mass m2 of the resin matrix, the mass m3 of the filler and the mass m4 of the accelerator satisfy the following: m1:m2:m3:m4 = (50 to 70):100:(40 to 70):(0.2 to 0.5).

[0051] In these embodiments, in the case where the resin matrix is a bismaleimide resin, the active ester resin, the resin matrix, the filler and the promoter are fully reacted in a mass ratio of (33 to 45): 100: (35 to 65): (0.3 to 0.6) to form a BCB end group-containing BMI molecule, which has good solubility, does not cause delamination and board explosion, and can effectively improve the thermal stability of the BMI cured product, thereby improving the heat resistance of the BMI-based copper-clad plate and reducing the dielectric constant of the copper-clad plate. In addition, in the case where the resin matrix is an epoxy resin, the active ester resin, the resin matrix, the filler and the promoter are fully reacted in a mass ratio of (50 to 70): 100: (40 to 70): (0.2 to 0.5) to form a BCB end group-containing epoxy resin solid product, which overcomes the problems of poor dielectric properties and high water absorption rate caused by traditional epoxy curing agents, and can improve the heat resistance of the epoxy resin-based copper-clad plate and reduce the dielectric constant of the copper-clad plate.

[0052] In the case where the resin matrix is a bismaleimide resin, the mass m1 of the active ester resin can be 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44 or 45. The mass m3 of the filler can be 35, 40, 45, 50, 55, 60 or 65. The mass m4 of the promoter can be 0.30, 0.35, 0.40, 0.45, 0.50, 0.55 or 0.60.

[0053] In the case where the resin matrix is an epoxy resin, the mass m1 of the active ester resin can be 50, 55, 60, 65 or 70. The mass m3 of the filler can be 40, 45, 50, 55, 60, 65 or 70. The mass m4 of the promoter can be 0.20, 0.25, 0.30, 0.35, 0.40, 0.45 or 0.50.

[0054] In some alternative embodiments, the bismaleimide resin comprises at least one of bis(3-ethyl-5-methyl-4-maleimide phenyl) methane, bis(3,5-diethyl-4-maleimide phenyl) methane, bis(4-maleimide phenyl) methane, bis(3,5-dimethyl-4-maleimide phenyl) methane, 2,2'-bis[4-(4-maleimide phenoxy) phenyl] propane, diphenyl methane bismaleimide and 2,2'-N,N'-m-phenylene bismaleimide; and / or The epoxy resin comprises at least one of dicyclopentadiene phenol epoxy resin, bisphenol A formaldehyde novolac epoxy resin, phenol formaldehyde novolac epoxy resin and o-cresol formaldehyde epoxy resin; and / or the accelerator includes at least one of 2,4,6-tris(dimethylaminomethyl)phenol, triphenylphosphine, 4-dimethylaminopyridine, 2-methylimidazole, and 1-benzyl-2-methylimidazole; and / or the filler includes at least one of silicon dioxide, montmorillonite, magnesium oxide, di-aluminum trioxide, and mica powder; and / or the second organic solvent includes at least one of acetone, butanone, methyl isobutyl ketone, toluene, propylene glycol monomethyl ether, and ethylene glycol methyl ether.

[0055] In these embodiments, the use of a bismaleimide resin including at least one of bis(3-ethyl-5-methyl-4-maleimide phenyl)methane, bis(3,5-diethyl-4-maleimide phenyl)methane, bis(4-maleimide phenyl)methane, bis(3,5-dimethyl-4-maleimide phenyl)methane, 2,2'-bis[4-(4-maleimide phenoxy)phenyl]propane, diphenylmethane bismaleimide, and 2,2'-N,N'-m-phenylene bismaleimide, the use of an accelerator including at least one of 2,4,6-tris(dimethylaminomethyl)phenol, triphenylphosphine, 4-dimethylaminopyridine, 2-methylimidazole, and 1-benzyl-2-methylimidazole, the use of a filler including at least one of silicon dioxide, montmorillonite, magnesium oxide, di-aluminum trioxide, and mica powder, and the use of a second organic solvent including at least one of acetone, butanone, methyl isobutyl ketone, toluene, propylene glycol monomethyl ether, and ethylene glycol methyl ether can be fully reacted to form a BCB end group-containing BMI molecule, which has good solubility, does not have delamination or board explosion, and can effectively improve the thermal stability of the BMI cured product, thereby improving the heat resistance of the BMI-based copper-clad plate and reducing the dielectric constant of the copper-clad plate. In addition, the use of an epoxy resin including at least one of dicyclopentadiene phenol epoxy resin, bisphenol A formaldehyde novolac epoxy resin, phenol formaldehyde novolac epoxy resin, and o-cresol formaldehyde novolac epoxy resin instead of the bismaleimide resin can enable the active ester resin, the resin matrix, the filler, and the accelerator to be fully reacted to form a BCB end group-containing epoxy resin solid product, which overcomes the problems of poor dielectricity and high water absorption rate caused by traditional epoxy curing agents, and can improve the heat resistance of the epoxy resin-based copper-clad plate and reduce the dielectric constant of the copper-clad plate.

[0056] The present application is further described below in conjunction with specific examples. The experimental methods in the following examples, for which no specific conditions are noted, are generally determined according to national standards / industry standards; if there are no corresponding national standards / industry standards, the methods are determined according to general international standards, conventional conditions, or according to the conditions suggested by the manufacturers.

[0057] Example 1

[0058] As Figure 1As shown, a method for preparing a benzocyclobutene-terminated active ester resin comprises: S1. Stirring and mixing an acyl chloride compound, a diallyl bisphenol A, a benzocyclobutene capping agent, and a first organic solvent to obtain a first mixture; S2. Dropping an acid-binding agent into the first mixture and performing a polymerization reaction to obtain a reaction product; S3. Purifying the reaction product and removing the first organic solvent to obtain a benzocyclobutene-terminated active ester resin.

[0059] The dropping time is 2.5 h.

[0060] The amount of substance n1 of the acyl chloride compound, the amount of substance n2 of the diallyl bisphenol A, and the amount of substance n3 of the benzocyclobutene capping agent satisfy: n1:n2:n3 = 1 mol:0.67 mol:0.67 mol.

[0061] The acid-binding agent is sodium carbonate; the amount of substance n4 of the acid-binding agent and the amount of substance n1 of the acyl chloride compound in the first mixture satisfy: n4:n1 = 2.04 mol:1 mol.

[0062] The first organic solvent comprises toluene and methyl isobutyl ketone, and the mass ratio of toluene to methyl isobutyl ketone is 3:1; the mass of the first organic solvent is 1700 g.

[0063] The acyl chloride compound comprises 2,2'-diphenyl dicarboxylic acid chloride.

[0064] The temperature of the polymerization reaction is 60°C, and the time of the polymerization reaction is 2 h.

[0065] Example 2

[0066] Compared with Example 1, the differences of Example 2 are as follows, and the rest are the same: The dropping time is 2.0 h.

[0067] The amount of substance n1 of the acyl chloride compound, the amount of substance n2 of the diallyl bisphenol A, and the amount of substance n3 of the benzocyclobutene capping agent satisfy: n1:n2:n3 = 1 mol:0.5 mol:1.0 mol.

[0068] The acid-binding agent is sodium carbonate; the amount of substance n4 of the acid-binding agent and the amount of substance n1 of the acyl chloride compound in the first mixture satisfy: n4:n1 = 2.03 mol:1 mol.

[0069] The first organic solvent comprises toluene and dimethylformamide, and the mass ratio of toluene to dimethylformamide is 4:1; the mass of the first organic solvent is 1660 g.

[0070] The acyl chloride compound is 4,4'-biphenyldicarboxylic acid chloride.

[0071] The polymerization reaction was carried out at a temperature of 50°C for 4 hours.

[0072] Example 3

[0073] Compared to Example 1, Example 3 differs as follows; all other aspects are the same: The dripping time is 3 hours.

[0074] The amounts of the acyl chloride compound n1, the amount of diallyl bisphenol A n2, and the amount of the benzocyclobutenyl end-capping agent n3 satisfy the following: n1:n2:n3 = 1 mol: 0.83 mol: 0.33 mol.

[0075] The acid-binding agent is trimethylamine; the amount of the acid-binding agent n4 and the amount of the acyl chloride compound n1 in the first mixture satisfy: n4:n1 = 2.05 mol: 1 mol.

[0076] The first organic solvent includes toluene and methyl ethyl ketone (MEK), with a mass ratio of toluene to MEK of 4:3; the mass of the first organic solvent is 1500g.

[0077] The acyl chloride-containing compound is isophthaloyl chloride.

[0078] The polymerization reaction was carried out at a temperature of 55°C for 3 hours.

[0079] Example 4

[0080] Compared to Example 1, Example 4 differs as follows; all other aspects are the same: The dripping time is 3 hours.

[0081] The amounts of the acyl chloride compound n1, the amount of diallyl bisphenol A n2, and the amount of the benzocyclobutenyl end-capping agent n3 satisfy the following: n1:n2:n3 = 1 mol: 0.88 mol: 0.25 mol.

[0082] The acid-binding agent is potassium carbonate; the amount of the acid-binding agent n4 and the amount of the acyl chloride compound n1 in the first mixture satisfy: n4:n1 = 2.03 mol: 1 mol.

[0083] The first organic solvent comprises xylene and dimethylformamide, wherein the mass ratio of xylene to dimethylformamide is 4:1; the mass of the first organic solvent is 1500g. The acyl chloride compound is phthaloyl chloride.

[0084] The polymerization reaction was carried out at a temperature of 70°C for 4 hours.

[0085] Example 5 Compared with embodiment 1, the difference of embodiment 5 is as follows, and the rest is the same: The time for dropping is 3 h.

[0086] The amount of substance n1 of the acyl chloride compound, the amount of substance n2 of the diallyl bisphenol A and the amount of substance n3 of the benzocyclobutenyl blocking agent satisfy: n1:n2:n3=1 mol:0.91 mol:0.18 mol.

[0087] The acid-binding agent is sodium carbonate; the amount of substance n4 of the acid-binding agent and the amount of substance n1 of the acyl chloride compound in the first mixture satisfy: n4:n1=2.05:1.

[0088] The first organic solvent includes toluene and butanone, and the mass ratio of toluene to butanone is 4:3; the mass of the first organic solvent is 1500 g.

[0089] The acyl chloride compound contained is terephthaloyl chloride.

[0090] The temperature of the polymerization reaction is 65℃, and the time of the polymerization reaction is 3 h.

[0091] Embodiment 6

[0092] As shown in Figure 2 A preparation method of a copper-clad plate, comprising: S1. mixing the active ester resin of embodiment 1, a resin matrix, a filler, a promoter and a second solvent to obtain a prepreg with a preset solid content; wherein the resin matrix is a bismaleimide resin; and the preset solid content is 65%; S2. using the prepreg with the preset solid content to perform impregnation treatment on a glass fiber cloth to obtain an impregnated glass fiber cloth; S3. baking the impregnated glass fiber cloth to obtain a prepreg; S4. laminating 8 prepregs to obtain a laminate; S5. covering copper foils on both sides of the laminate and performing vacuum hot pressing to obtain a copper-clad plate.

[0093] In the case where the resin matrix is a bismaleimide resin, the mass m1 of the active ester resin, the mass m2 of the resin matrix, the mass m3 of the filler and the mass m4 of the promoter satisfy: m1:m2:m3:m4=38:100:50:0.5.

[0094] The bismaleimide resin is bis(4-maleimido phenyl) methane; The promoter is 2-methyl imidazole; The filler is silicon dioxide; The second organic solvent is butanone, and the mass ratio of the second organic solvent to the resin matrix is 102:100.

[0095] The preset solid content is 65%.

[0096] The baking temperature is 160℃, and the baking time is 7min.

[0097] The specific operation of vacuum hot pressing includes: first, the temperature of the stack is raised from room temperature to 200℃ at a rate of 3℃ / min, at the same time, the pressure is raised from 0.2MPa to 4MPa at a rate of 0.1MPa / min, and the stack and copper foil are vacuumed to within 80torr, and the pressure is kept for 2h to obtain a pressure body; then the pressure body is raised to 220℃, and kept for 5h under the condition of constant pressure (4MPa).

[0098] Example 7 Compared with Example 4, the difference of Example 7 is as follows, and the rest is the same: The active ester resin is the active ester resin of Example 2.

[0099] The resin matrix is a bismaleimide resin.

[0100] In the case of the resin matrix being a bismaleimide resin, the mass m1 of the active ester resin, the mass m2 of the resin matrix, the mass m3 of the filler, and the mass m4 of the promoter satisfy: m1:m2:m3:m4=45:100:55:0.4.

[0101] The bismaleimide resin is 2,2'-N,N'-m-phenylene bismaleimide; The promoter is 4-dimethylaminopyridine; The filler is montmorillonite; The second organic solvent is methyl isobutyl ketone, and the ratio of the mass of the second organic solvent to the mass of the resin matrix is 123:100.

[0102] The preset solid content is 62%.

[0103] The baking temperature is 180℃, and the baking time is 5min.

[0104] The pressure is kept for 1h to obtain a pressure body; then the pressure body is raised to 235℃, and kept for 4h under the condition of constant pressure (4MPa).

[0105] Example 8

[0106] Compared with Example 4, the difference of Example 8 is as follows, and the rest is the same: The active ester resin is the active ester resin of Example 3.

[0107] The resin matrix is a bismaleimide resin.

[0108] In the case where the resin matrix is a bismaleimide resin, the mass m1 of the active ester resin, the mass m2 of the resin matrix, the mass m3 of the filler, and the mass m4 of the accelerator satisfy: m1:m2:m3:m4=36:100:52:0.4.

[0109] The bismaleimide resin is 2,2'-bis[4-(4-maleimido phenoxy)phenyl]propane; The accelerator is triphenylphosphine; The filler is mica powder; The second organic solvent is acetone, and the ratio of the mass of the second organic solvent to the mass of the resin matrix is 101:100.

[0110] The preset solid content is 65%.

[0111] The baking temperature is 175°C, and the baking time is 6 min.

[0112] The pressing is maintained under the pressure for 1.5 h to obtain a pressed body; the pressed body is then heated to 225°C and maintained under a constant pressure (4 MPa) for 5.5 h.

[0113] Example 9 Compared with Example 4, the differences of Example 9 are as follows, and the rest are the same: The active ester resin is the active ester resin of Example 4.

[0114] The resin matrix is a bismaleimide resin.

[0115] In the case where the resin matrix is a bismaleimide resin, the mass m1 of the active ester resin, the mass m2 of the resin matrix, the mass m3 of the filler, and the mass m4 of the accelerator satisfy: m1:m2:m3:m4=35:100:48:0.5.

[0116] The bismaleimide resin is diphenylmethane bismaleimide; The accelerator is 1-benzyl-2-methylimidazole; The filler is aluminum trioxide; The second organic solvent is ethylene glycol methyl ether, and the ratio of the mass of the second organic solvent to the mass of the resin matrix is 95:100.

[0117] The preset solid content is 66%.

[0118] The baking temperature is 175°C, and the baking time is 5 min.

[0119] The pressing is maintained under the pressure for 1.5 h to obtain a pressed body; the pressed body is then heated to 220°C and maintained under a constant pressure (4 MPa) for 6.0 h.

[0120] Example 10

[0121] The difference between Example 10 and Example 4 is as follows, and the rest is the same: The active ester resin is the active ester resin of Example 5.

[0122] The resin matrix is a bismaleimide resin.

[0123] In the case where the resin matrix is a bismaleimide resin, the mass m1 of the active ester resin, the mass m2 of the resin matrix, the mass m3 of the filler, and the mass m4 of the accelerator satisfy: m1:m2:m3:m4=40:100:55:0.4.

[0124] The bismaleimide resin is bis(3-ethyl-5-methyl-4-maleimide phenyl)methane; The accelerator is 2,4,6-tris(dimethylaminomethyl)phenol; The filler is magnesium oxide; The second organic solvent is butanone, and the ratio of the mass of the second organic solvent to the mass of the resin matrix is 92:100.

[0125] The preset solid content is 68%.

[0126] The temperature of the baking is 185°C, and the time of the baking is 5 min.

[0127] The pressing is kept under the pressure for 2.0 h to obtain a pressing body; and then the pressing body is heated to 235°C, and kept under the constant pressure (4 MPa) for 4.0 h.

[0128] Example 11 The difference between Example 11 and Example 4 is as follows, and the rest is the same: The active ester resin is the active ester resin of Example 1.

[0129] The resin matrix is an epoxy resin.

[0130] In the case where the resin matrix is an epoxy resin, the mass m1 of the active ester resin, the mass m2 of the resin matrix, the mass m3 of the filler, and the mass m4 of the accelerator satisfy: m1:m2:m3:m4=62:100:54:0.3.

[0131] The epoxy resin is o-cresol formaldehyde epoxy resin; The accelerator is 2,4,6-tris(dimethylaminomethyl)phenol; The filler is mica powder; The second organic solvent is acetone, and the ratio of the mass of the second organic solvent to the mass of the resin matrix is 127:100.

[0132] The specific operation of vacuum hot pressing includes: first, the stack is heated from room temperature to 180℃ at a heating rate of 3℃ / min, at the same time, the pressure is increased from 0.2MPa to 4MPa at a rate of 0.1MPa / min, and the stack and copper foil are vacuumed to within 80torr, and the pressure is kept for 1h to obtain a pressure body; then the pressure body is heated to 220℃, and kept for 3h under the condition of constant pressure (4MPa).

[0133] Example 12

[0134] Compared with Example 11, the difference of Example 12 is as follows, and the rest is the same: The active ester resin is the active ester resin of Example 2.

[0135] The resin matrix is an epoxy resin.

[0136] In the case of the resin matrix being an epoxy resin, the mass m1 of the active ester resin, the mass m2 of the resin matrix, the mass m3 of the filler and the mass m4 of the promoter satisfy: m1:m2:m3:m4=58:100:65:0.4.

[0137] The epoxy resin is a bisphenol A formaldehyde novolac epoxy resin; The promoter is triphenylphosphine; The filler is silicon dioxide; The second organic solvent is propylene glycol monomethyl ether, and the ratio of the mass of the second organic solvent to the mass of the resin matrix is 115:100.

[0138] The preset solid content is 66%.

[0139] The temperature of the baking is 160℃, and the time of the baking is 6min.

[0140] The pressure is kept for 1.5h to obtain a pressure body; then the pressure body is heated to 210℃, and kept for 5.0h under the condition of constant pressure (4MPa).

[0141] Example 13 Compared with Example 11, the difference of Example 13 is as follows, and the rest is the same: The active ester resin is the active ester resin of Example 4.

[0142] The resin matrix is an epoxy resin.

[0143] In the case of the resin matrix being an epoxy resin, the mass m1 of the active ester resin, the mass m2 of the resin matrix, the mass m3 of the filler and the mass m4 of the promoter satisfy: m1:m2:m3:m4=62:100:48:0.5.

[0144] The epoxy resin is a dicyclopentadiene phenol epoxy resin; The accelerator is 2-methylimidazole; The filler is montmorillonite; The second organic solvent is toluene, and the ratio of the mass of the second organic solvent to the mass of the resin matrix is 115:100.

[0145] The preset solid content is 65%.

[0146] The baking temperature is 185°C, and the baking time is 3 min.

[0147] The compression is maintained under pressure for 2.0 h to obtain a compression body; the compression body is then heated to 225°C and maintained under constant pressure (4 MPa) for 4.0 h.

[0148] Comparative Example 1 Comparative Example 1 differs from Example 6 as follows, and the rest are the same: The active ester resin is replaced by an active ester curing agent, which is DFE616L provided by Sichuan Dongcai Science and Technology Group Co., Ltd.

[0149] The preset solid content is 65%.

[0150] The baking temperature is 160°C, and the baking time is 7 min.

[0151] The compression is maintained under pressure for 2 h to obtain a compression body; the compression body is then heated to 220°C and maintained under constant pressure (4 MPa) for 5 h.

[0152] Comparative Example 2 Comparative Example 1 differs from Example 7 as follows, and the rest are the same: The active ester resin is replaced by an active ester curing agent, which is DFE616L provided by Sichuan Dongcai Science and Technology Group Co., Ltd.

[0153] The preset solid content is 62%.

[0154] The baking temperature is 180°C, and the baking time is 5 min.

[0155] The compression is maintained under pressure for 1 h to obtain a compression body; the compression body is then heated to 235°C and maintained under constant pressure (4 MPa) for 4 h.

[0156] Comparative Example 3 Comparative Example 1 differs from Example 8 as follows, and the rest are the same: The active ester resin is replaced by an active ester curing agent, which is DFE616L provided by Sichuan Dongcai Science and Technology Group Co., Ltd.

[0157] The preset solid content is 65%.

[0158] The baking temperature is 175℃, and the baking time is 6min.

[0159] The pressing is kept under the pressure for 1.5h to obtain a pressing body; the pressing body is heated to 225℃, and kept for 5.5h under the constant pressure (4MPa).

[0160] Comparative Example 4 Comparative Example 1 is different from Comparative Example 9 as follows, and the rest is the same: The active ester resin is replaced by an active ester curing agent, which is DFE616L provided by Sichuan Dongcai Science and Technology Group Co., Ltd.

[0161] The preset solid content is 66%.

[0162] The baking temperature is 175℃, and the baking time is 5min.

[0163] The pressing is kept under the pressure for 1.5h to obtain a pressing body; the pressing body is heated to 220℃, and kept for 6.0h under the constant pressure (4MPa).

[0164] Comparative Example 5 Comparative Example 1 is different from Comparative Example 10 as follows, and the rest is the same: The active ester resin is replaced by an active ester curing agent, which is DFE616L provided by Sichuan Dongcai Science and Technology Group Co., Ltd.

[0165] The preset solid content is 68%.

[0166] The baking temperature is 185℃, and the baking time is 5min.

[0167] The pressing is kept under the pressure for 2.0h to obtain a pressing body; the pressing body is heated to 235℃, and kept for 4.0h under the constant pressure (4MPa).

[0168] Comparative Example 6 Comparative Example 1 is different from Comparative Example 11 as follows, and the rest is the same: The active ester resin is replaced by an active ester curing agent, which is DFE616L provided by Sichuan Dongcai Science and Technology Group Co., Ltd.

[0169] The preset solid content is 63%.

[0170] The baking temperature is 170℃, and the baking time is 4min.

[0171] The compression body was obtained by keeping compression under pressure for 1.0 h, and then the compression body was heated to 220 ℃ and kept for 3.0 h under constant pressure (4 MPa).

[0172] Comparative Example 7 Comparative Example 1 is different from Comparative Example 12 as follows, and the rest is the same: The active ester resin was replaced by an active ester curing agent, which was DFE616L provided by Sichuan Dongcai Science and Technology Group Co., Ltd.

[0173] The preset solid content was 66%.

[0174] The baking temperature was 160 ℃, and the baking time was 6 min.

[0175] The compression body was obtained by keeping compression under pressure for 1.5 h, and then the compression body was heated to 210 ℃ and kept for 5.0 h under constant pressure (4 MPa).

[0176] Comparative Example 8 Comparative Example 1 is different from Comparative Example 13 as follows, and the rest is the same: The active ester resin was replaced by an active ester curing agent, which was DFE616L provided by Sichuan Dongcai Science and Technology Group Co., Ltd.

[0177] The preset solid content was 65%.

[0178] The baking temperature was 185 ℃, and the baking time was 3 min.

[0179] The compression body was obtained by keeping compression under pressure for 2.0 h, and then the compression body was heated to 225 ℃ and kept for 4.0 h under constant pressure (4 MPa).

[0180] Related experiments and effect data: 1. The copper-clad plates obtained in Examples 6 to 10 and Comparative Examples 1 to 5 were collected respectively, and their performances were detected, and the results are shown in Table 1. Among them, the glass transition temperature Tg was determined by dynamic mechanical analysis (DMA) according to the DMA method specified in IPC-TM-650 2.4.24.4; the dielectric constant Dk and the dielectric loss Df were tested by SPDR method according to the method specified in IEC61189-2-721 to test 10 GHz data; the bending strength and bending modulus were tested by three-point bending performance test according to GB / T 14452-1993 standard.

[0181] Table 1 Performance data of copper-clad plates obtained in Examples 6 to 10 and Comparative Examples 1 to 5 2. The copper-clad plates obtained in Example 11 to Example 13 and Comparative Example 6 to Comparative Example 8 were collected respectively, and the properties were detected, and the results are shown in Table 2. Among them, the water absorption test: the test was carried out according to the standard of GB / T 1034-2008.

[0182] Table 2 Performance data of the copper-clad plates obtained in Example 11 to Example 13 and Comparative Example 6 to Comparative Example 8 As can be seen from Table 1, the preparation method of the active ester resin terminated by a benzocyclobutene group provided in the embodiments of the present application reduces the intermolecular force and improves the polarity matching by molecular structure design and reaction control, so as to improve the solubility of the BCB end group-containing BMI. In addition, the high-solubility BMI molecule of the preparation method can also obtain a copper-clad plate with high heat resistance, high mechanical strength, low dielectric constant and low dielectric loss.

[0183] As can be seen from Table 2, the preparation method of the copper-clad plate provided in the embodiments of the present application can be used in traditional epoxy resins in addition to preparing high-solubility BMI molecules, so as to finally prepare a copper-clad plate with high heat resistance, low dielectric constant and low dielectric loss.

[0184] In summary, the preparation method of the active ester resin terminated by a benzocyclobutene group provided in the embodiments of the present application effectively reduces the intermolecular force of the BCB end group-containing BMI by the synergistic effect of flexible chain segment embedding + end group polarity adjustment + main chain polarity optimization + molecular weight control, improves the compatibility of the BCB end group-containing BMI with organic solvents, and thus improves the solubility of the BMI molecule.

[0185] In addition, the preparation method of the active ester resin terminated by a benzocyclobutene group provided in the embodiments of the present application introduces a BCB group into the active ester resin, which improves the dielectric properties of the active ester resin. In addition, under high temperature conditions, the Diels-Alder addition reaction can make the allyl group and the BMI form a benzohexacyclic ring structure, which can effectively enhance the heat resistance of the BMI system, and no by-products or small molecules are produced in the process, effectively avoiding the delamination and explosion of the copper-clad plate during lamination or soldering.

[0186] In addition, the preparation method of the active ester resin terminated by a benzocyclobutene group provided in the embodiments of the present application not only guarantees the toughening performance of the active ester resin by introducing an allyl structure, but also overcomes the problem of reduced dielectric properties of the copper-clad plate caused by the diallyl bisphenol A, and can also increase the solubility of the BMI molecule or the epoxy resin, expand the application scenarios of the BMI molecule or the epoxy resin, and improve the application range of the copper-clad plate.

[0187] In addition, the application provides a preparation method of the benzocyclobutene-based active ester resin, the active ester resin obtained by the preparation method can be used as a curing agent of an epoxy resin in addition to being used for a BMI base resin, compared with traditional phenolic, anhydride and amine curing agents, the active ester resin does not have a polar hydroxyl group, and the problems of poor dielectricity and high water absorption caused by traditional epoxy curing agents are overcome, and the prepared copper-clad plate has good performance parameters.

[0188] In addition, the application provides a preparation method of a copper-clad plate, the overall process of the preparation method is simple, easy to operate and has high practicability.

[0189] The above describes only the specific embodiments of the application, so that those skilled in the art can understand or implement the application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined in the application can be implemented in other embodiments without departing from the spirit or scope of the application. Therefore, the application will not be limited to these embodiments shown in the application, but will conform to the widest range consistent with the principles and novel features of the application.

Claims

1. A process for the preparation of a benzocyclobutene-terminated active ester resin, characterized in that, The preparation method comprises: stirring and mixing an acyl chloride compound, a diallyl bisphenol A, a benzocyclobutenyl capping agent and a first organic solvent to obtain a first mixture; adding a deacidifying agent dropwise into the first mixture and performing a polymerization reaction to obtain a reaction product; purifying the reaction product and removing the first organic solvent to obtain a benzocyclobutenyl-capped active ester resin.

2. The production method according to claim 1, characterized by, The molar amount n1 of the acyl chloride compound, the molar amount n2 of the diallyl bisphenol A and the molar amount n3 of the benzocyclobutenyl capping agent satisfy: n1:n2:n3=1:(0.50 to 0.91):(0.18 to 1.00).

3. The production method according to claim 1, characterized by, The deacidifying agent comprises any one of triethylamine, trimethylamine, pyridine, sodium carbonate, potassium carbonate and potassium hydroxide; the molar amount n4 of the deacidifying agent and the molar amount n1 of the acyl chloride compound in the first mixture satisfy: n4:n1=(2.03 to 2.05):

1.

4. The method of claim 1, wherein, The first organic solvent comprises at least two of toluene, xylene, butanone, methyl isobutyl ketone and dimethylformamide; and / or The acyl chloride compound comprises at least one of 2,2'-biphenyl dicarboxylic acid chloride, 4,4'-biphenyl dicarboxylic acid chloride, isophthaloyl chloride, terephthaloyl chloride and phthaloyl chloride.

5. The preparation method according to claim 1, characterized in that, The temperature of the polymerization reaction is 50 to 80°C, and the time of the polymerization reaction is 1 to 4h.

6. A benzocyclobutene-based end-capped active ester resin characterized in that, The active ester resin is obtained by the preparation method of any one of claims 1 to 5; the active ester resin has a molecular structure as shown in formula 1, Formula 1, In Formula 1, R includes at least one of , , , and ; n has a value of 1 to 10.

7. A copper clad plate characterized by, The copper-clad plate comprises the active ester resin of claim 6.

8. A method for producing a copper clad plate, characterized by, The preparation method comprises: mixing the active ester resin of claim 6, a resin matrix, a filler, an accelerator and a second solvent to obtain a prepreg with a preset solid content; wherein the resin matrix is a bismaleimide resin or an epoxy resin; the preset solid content is 60% to 70%; using the prepreg with the preset solid content to perform an impregnation treatment on a glass fiber cloth to obtain an impregnated glass fiber cloth; baking the impregnated glass fiber cloth to obtain a prepreg; stacking the prepreg to obtain a laminate; covering copper foils on two sides of the laminate and performing vacuum hot pressing to obtain a copper-clad plate.

9. The production method according to claim 8, characterized by, In the case where the resin matrix is a bismaleimide resin, the mass m1 of the active ester resin, the mass m2 of the resin matrix, the mass m3 of the filler and the mass m4 of the accelerator satisfy: m1:m2:m3:m4=(33 to 45):100:(35 to 65):(0.3 to 0.6); and / or In the case where the resin matrix is an epoxy resin, the mass m1 of the active ester resin, the mass m2 of the resin matrix, the mass m3 of the filler and the mass m4 of the accelerator satisfy: m1:m2:m3:m4=(50 to 70):100:(40 to 70):(0.2 to 0.5).

10. The preparation method according to claim 8, characterized in that, The bismaleimide resin includes at least one of bismaleimide of 3-ethyl-5-methyl-4-maleimide phenyl methane, bismaleimide of 3,5-diethyl-4-maleimide phenyl methane, bismaleimide of 4-maleimide phenyl methane, bismaleimide of 3,5-dimethyl-4-maleimide phenyl methane, 2,2'-bis[4-(4-maleimide phenoxy) phenyl] propane, xylylene bismaleimide, and 2,2'-N,N'-m-phenylene bismaleimide; and / or The epoxy resin includes at least one of dicyclopentadiene phenol epoxy resin, bisphenol A formaldehyde novolac epoxy resin, phenol formaldehyde novolac epoxy resin, and o-cresol formaldehyde epoxy resin; and / or The accelerator includes at least one of 2,4,6-tris(dimethylaminomethyl) phenol, triphenylphosphine, 4-dimethylaminopyridine, 2-methylimidazole, and 1-benzyl-2-methylimidazole; and / or The filler includes at least one of silicon dioxide, montmorillonite, magnesium oxide, diatomic aluminum oxide, and mica powder; and / or The second organic solvent includes at least one of acetone, butanone, methyl isobutyl ketone, toluene, propylene glycol monomethyl ether, and ethylene glycol methyl ether.

Images