CN109810467B

CN109810467B - Thermosetting resin composition, and prepreg and laminated board prepared from thermosetting resin composition

Info

Publication number: CN109810467B
Application number: CN201910075087.1A
Authority: CN
Inventors: 何继亮; 陈诚; 王宁; 黄荣辉; 马建; 崔春梅; 储正振
Original assignee: Suzhou Shengyi Technology Co Ltd
Current assignee: Suzhou Shengyi Technology Co Ltd
Priority date: 2019-01-25
Filing date: 2019-01-25
Publication date: 2021-12-28
Anticipated expiration: 2039-01-25
Also published as: CN109810467A

Abstract

The invention discloses a thermosetting resin composition, which comprises the following components in parts by weight: (a) epoxy resin: 100 parts of (A); (b) unsaturated polyester active ester resin modified by vinyl crosslinking agent: 50-300 parts; (c) accelerator (b): 0.05-4 parts. The unsaturated polyester active ester resin modified by the vinyl cross-linking agent can effectively combine an active ester cured epoxy resin system and a hydrocarbon resin cured system in a chemical bond form, and effectively combine the excellent performance of the active ester cured epoxy system and the excellent performance of the hydrocarbon resin, so that the resin composition has excellent dielectric property, heat resistance, strength, rigidity and flexibility after being cured, high peel strength, low water absorption and small heat shrinkage, and can be applied to high-speed and high-frequency printed circuit boards.

Description

Thermosetting resin composition, and prepreg and laminated board prepared from thermosetting resin composition

Technical Field

The invention relates to a thermosetting resin composition, and a prepreg and a laminated board prepared from the thermosetting resin composition, and belongs to the technical field of electronic materials.

Background

In recent years, with the progress of high-speed and high-frequency information processing and information transmission technologies, higher and higher requirements are being made on dielectric properties of printed circuit board materials. In short, the printed circuit board material needs to have a low dielectric constant and dielectric loss tangent to reduce the delay, distortion and loss of signals during high-speed transmission and the interference between signals. Accordingly, it is desirable to provide a thermosetting resin composition which can exhibit a sufficiently low dielectric constant and a sufficiently low dielectric loss tangent in a signal transmission process of high speed and high frequency, in a printed circuit board material produced using the thermosetting resin composition.

In view of the above problems, in the prior art, an epoxy resin system cured with an active ester resin can give a cured product excellent in dielectric properties. However, epoxy resins cured with active ester resins have a problem of insufficient heat resistance, and it is difficult to achieve both heat resistance and low dielectric constant and low dielectric loss tangent, and thus they cannot meet the requirements of practical applications of materials.

On the other hand, hydrocarbon resins, such as polybutadiene, and copolymers of butadiene and styrene, also have excellent dielectric properties, and are becoming one of the mainstream technologies in this field. However, a great deal of research shows that although hydrocarbon resin can provide good dielectric properties, due to the flexible and nonpolar carbon chain structure of hydrocarbon resin, the cured hydrocarbon resin has the problems of insufficient rigidity, low strength, poor heat resistance, low glass transition temperature, poor adhesion and the like, and many problems still need to be solved in practical application.

Therefore, it has been one of the main research and development directions in the field to develop a novel thermosetting resin composition which can be used to produce a printed circuit board material that exhibits a sufficiently low dielectric constant and a low dielectric loss tangent in a signal transmission process with a high speed and a high frequency.

Disclosure of Invention

The invention aims to provide a thermosetting epoxy resin composition and a prepreg and a laminated board prepared by applying the thermosetting epoxy resin composition.

In order to achieve the purpose of the invention, the technical scheme adopted by the invention is as follows: a thermosetting resin composition comprising, in parts by weight:

(a) epoxy resin: 100 parts of (A);

(b) unsaturated polyester active ester resin modified by vinyl crosslinking agent: 50-300 parts;

(c) accelerator (b): 0.05-4 parts;

the alkene crosslinking agent modified unsaturated polyester active ester is prepared by reacting alkene monomer and unsaturated polyester

Mixtures or prepolymers of active esters, initiators, mixtures of said unsaturated polyester active esters

The structural formula is as follows:

wherein:

the value of n is 0.5-10;

X₁selected from-CH = CH-),

And must contain-CH = CH-;

Y₁one or more selected from the following groups:

naphthylene ethers of the formula

Middle Z₁Is isopropylidene, cyclopentadienyl, sulfuryl, methylene or oxygen atom, Rx is hydrogen atom or alkyl with carbon atom number less than or equal to 5;

ra is a hydrogen atom, benzoyl, substituted benzoyl or alkanoyl;

rb is a hydrogen atom, a phenyl group or a substituted phenyl group.

As mentioned above, the unsaturated polyester active ester modified by the vinyl crosslinking agent is a mixture or prepolymer obtained by mixing a vinyl monomer, an unsaturated polyester active ester and an initiator together; when the mixture is a mixture of vinyl monomer, unsaturated polyester active ester and initiator, the mixture is in a physical blending state, but in the subsequent heating process, the vinyl monomer and the unsaturated polyester active ester still undergo a chemical reaction under the action of the initiator to form a polymer.

The amount of the alkene crosslinking agent modified unsaturated polyester active ester resin can be 55 parts, 60 parts, 65 parts, 70 parts, 90 parts, 100 parts, 120 parts, 150 parts, 180 parts, 200 parts, 210 parts, 230 parts, 250 parts, 260 parts, 270 parts, 280 parts, 290 parts and 295 parts.

In the structural formula of the unsaturated polyester active ester, the value of n is 0.5-10, and can be 1, 2, 3, 4, 5, 6, 7, 8 and 9, preferably an integer of 1-10, more preferably 1-8, more preferably 2-6, and more preferably 3-5.

Said X₁Selected from-CH = CH-),

And must contain-CH = CH-;

X₁may have a certain proportion of groups

A group; when X is present₁With a certain proportion of radicals

When in use, the problem of stickiness of hydrocarbon resin can be effectively improved,

preferably in a ratio of total X₁10 to 50% of the total amount of the organic solvent.

The alkene crosslinking agent modified unsaturated polyester active ester also comprises 0.05-25 parts of initiator. The initiator is a compound which is decomposed into free radicals by heat energy, can be used for initiating free radical polymerization and copolymerization of alkene and diene monomers, and can also be used for crosslinking curing and high molecular crosslinking reaction of unsaturated polyester. The initiator can be azo initiator, peroxy initiator and redox initiator, and can be one or more of the following initiators: tert-butyl hydroperoxide, dicumyl peroxide, di-tert-butyl peroxide, tert-butyl peroxybenzoate, dicyclohexyl peroxydicarbonate, cumene hydroperoxide, azobisisobutyronitrile and benzoyl peroxide. The initiator is preferably one or more of tert-butyl hydroperoxide, dicumyl peroxide, di-tert-butyl peroxide and tert-butyl peroxybenzoate. The addition amount of the initiator is 0.005-10 parts by weight, and the specific addition amount can be as follows: 0.005 parts by weight, 0.01 parts by weight, 0.02 parts by weight, 0.05 parts by weight, 0.10 parts by weight, 0.20 parts by weight, 0.50 parts by weight, 1 part by weight, 3 parts by weight, 5 parts by weight, 8 parts by weight, 10 parts by weight.

In the above, the molecular structure of the unsaturated polyester active ester in the component (b) has not only reactive unsaturated double bonds, but also active ester groups capable of performing curing reaction with the epoxy resin, the whole molecular chain has many reactive functional groups, the crosslinking density after curing and crosslinking is high, and the heat resistance and the mechanical strength of the resin curing system can be effectively improved. The special structure of the component (b) effectively combines an active ester cured epoxy resin system and a hydrocarbon resin cured system in a chemical bond form, the active ester cured epoxy system endows the resin system with better adhesive property, improves the peeling strength between the copper foil layer and the resin layer of the laminated board, does not influence the dielectric property of the resin system, and the hydrocarbon resin cured system endows the material with very good dielectric property and toughness.

In the above technical scheme, the epoxy resin is selected from one or more of bisphenol a epoxy resin, bisphenol F epoxy resin, phosphorus-containing epoxy resin, nitrogen-containing epoxy resin, o-cresol novolac epoxy resin, bisphenol a novolac epoxy resin, phenol novolac epoxy resin, cresol novolac epoxy resin, triphenylmethane epoxy resin, tetraphenylethane epoxy resin, biphenyl type epoxy resin, naphthalene type epoxy resin, dicyclopentadiene type epoxy resin, isocyanate type epoxy resin, aralkyl type novolac epoxy resin, polyphenylene oxide modified epoxy resin, alicyclic type epoxy resin, glycidylamine type epoxy resin, and glycidylester type epoxy resin.

Preferably, the epoxy resin is selected from one or more of biphenyl type epoxy resin, naphthalene ring type epoxy resin, dicyclopentadiene type epoxy resin and aralkyl novolac epoxy resin.

In the above technical scheme, the accelerant is selected from one or more of the following substances: dimethylaminopyridine, tertiary amines and their salts, imidazoles, organometallic salts, triphenylphosphine and its phosphonium salts. Preferably dimethylaminopyridine; the specific addition amount can be as follows: 0.005 parts by weight, 0.01 parts by weight, 0.02 parts by weight, 0.05 parts by weight, 0.10 parts by weight, 0.20 parts by weight, 0.50 parts by weight, 1 part by weight, 2 parts by weight, 3 parts by weight, 4 parts by weight.

In the technical scheme, the ratio of the alkene monomer to the unsaturated polyester active ester is 0.05: 1-5: 1 in terms of the functional equivalent of an unsaturated double bond. Preferably 0.5:1 to 4:1, more preferably 1:1 to 3:1, more preferably 2:1 to 3:1, and preferably 2.5: 1.

In the above technical scheme, the vinyl monomer is selected from one or more of styrene, substituted styrene, methyl acrylate, substituted methyl acrylate and maleimide resin, and the vinyl monomer must contain maleimide resin. Preferably, the vinyl monomer contains maleimide resin; the maleimide resin is bismaleimide, monomaleimide and polymaleimide. The mass ratio of the maleimide resin to the sum of other alkene crosslinking agents is 5: 100-50: 100. The addition of the vinyl monomer can well improve the wettability of the thermosetting resin system on the glass fiber cloth.

In the technical scheme, the polyurethane resin composition further comprises a component (d), wherein the component (d) is one or more selected from hydrocarbon resin, vinyl modified bismaleimide, vinyl modified polyphenyl ether, vinyl modified benzoxazine resin, vinyl modified phenolic resin, olefin copolymer, petroleum resin and single-component polyurethane resin. The component (d) is preferably one or more of hydrocarbon resin, vinyl modified bismaleimide, vinyl modified polyphenyl ether, vinyl modified benzoxazine resin and vinyl modified phenolic resin.

Preferably, the vinyl-modified phenolic resin is vinyl-modified maleimide phenolic resin, vinyl-modified novolac phenolic resin or dicyclopentadiene-vinylbenzyl phenyl ether. The dicyclopentadiene-vinylbenzylphenylate resin has the following structure:

wherein Ry₂Is a hydrogen atom or a hydrocarbon group, and n is an integer of 1 to 10.

In the technical scheme, the hydrocarbon resin is selected from one or more of styrene-butadiene resin, polybutadiene resin and polyisobutylene diene resin. Preferably, the hydrocarbon resin in the above technical scheme is a hydrocarbon resin with a number average molecular weight of less than 11000, a vinyl content of more than 60% and liquid at room temperature. Preferably, the hydrocarbon resin has a number average molecular weight of less than 7000. The hydrocarbon resin in the component (d) may specifically be: 10 parts by weight, 20 parts by weight, 40 parts by weight, 50 parts by weight, 60 parts by weight, 80 parts by weight, 100 parts by weight, 150 parts by weight, 200 parts by weight.

The vinyl modified bismaleimide in the component (d) is selected from a prepolymer generated by prepolymerization of an allyl compound and a maleimide resin, wherein the allyl compound is selected from one or more of allyl ether compounds, allyl phenolic oxygen resin, allyl phenolic resin, diallyl bisphenol A and diallyl bisphenol S; the maleimide resin is selected from one or more of 4,4 '-diphenylmethane bismaleimide resin, 4' -diphenyl ether bismaleimide resin, 4 '-diphenyl isopropyl bismaleimide resin and 4, 4' -diphenyl sulfone bismaleimide resin. Preferably, the number average molecular weight of the vinyl modified bismaleimide is 2000-5000 g/mol.

The vinyl modified polyphenyl ether of the component (d) is selected from one or more of unsaturated double bond modified polyphenyl ethers such as styrene modified polyphenyl ether, substituted styrene modified polyphenyl ether, acrylate modified polyphenyl ether, substituted acrylate modified polyphenyl ether and the like. The addition ratio of the vinyl modified polyphenylene ether is 20-200 parts by weight. The vinyl modified polyphenylene ether can further optimize the heat resistance and the dielectric property, and particularly has a remarkable effect of reducing the dielectric loss tangent value of a resin system, but the improvement of the adhesive property of the resin system is limited by adding too much. Preferably, the vinyl-modified polyphenylene ether has a molecular weight of less than 5000. Preferably, the vinyl-modified polyphenylene ether is selected from one or more compounds shown in the following structural formulas (I), (II) and (III):

structural formula (I):

wherein X₂Selected from the following structures:

wherein R is₁、R₃、R₆、R₈、R₉、R₁₁、R₁₄、R₁₆、R₁₇、R₁₉、R₂₂、R₂₄The same or different, respectively is a halogen atom, an alkyl group or a phenyl group; wherein R is₂、R₄、R₅、R₇、R₁₀、R₁₂、R₁₅、R₁₈、R₂₀、R₂₁、R₂₃The same or different, each is a hydrogen atom, a halogen atom, an alkyl group or a phenyl group;

in the structural formula (I) < CHEM > -Y₂-O-structure is:

wherein R is₂₆、R₂₈Identical or different, each being a halogen atom, an alkyl group or a phenyl group, R₂₅、R₂₇Are respectively selected from hydrogen atom, halogen atom, alkyl or phenyl;

in the structural formula (I), m and n represent integers of 0-30 respectively and cannot be 0 at the same time.

Structural formula (ii):

wherein n is an integer greater than 5.

Structural formula (iii):

wherein Y is₃Comprises the following steps:

wherein m and n are integers of 1 or more.

The vinyl modified benzoxazine resin in the component (d) is selected from one or more of allyl modified bisphenol A type benzoxazine, allyl modified bisphenol g type benzoxazine, allyl modified bisphenol S type benzoxazine, bisphenol diamine type benzoxazine and allyl modified dicyclopentadiene phenol type benzoxazine. Preferably, the addition ratio of the allyl modified benzoxazine resin is 1-20 parts by weight. The heat resistance and the bonding property can be further optimized by adding a proper amount of the (d) allyl modified benzoxazine resin, but the dielectric property and the toughness of the resin system are adversely affected by adding too much allyl modified benzoxazine resin.

The vinyl modified phenolic resin in the component (d) is preferably one or more of vinyl modified linear phenolic resin, vinyl modified maleimide phenolic resin and dicyclopentadiene-ethylene benzyl phenyl ether, and more preferably dicyclopentadiene-ethylene benzyl phenyl ether.

The vinyl-modified novolac resin has a structure of:

wherein Ry₁Is a hydrogen atom or a hydrocarbon group, and n is an integer of 1 to 10.

The vinyl modified maleimide-based phenolic resin in the component (d) is a resin with the following structure:

wherein m is 2-20, n is 1-10, and k is 1-10.

The petroleum resin in the component (d) is selected from one or more of alicyclic petroleum resin (DCPD), aromatic petroleum resin (C9) and aliphatic/aromatic copolymerized petroleum resin (C5/C9). Preferably, the molecular weight of the petroleum resin is 1000-3000 g/mol. Preferably, the petroleum resin is added in a proportion of 5-25 parts by weight. The addition of a proper amount of the petroleum resin as the component (d) can further optimize the dielectric property and the adhesive property of the resin system, improve the flowing property of the resin system and improve the process property.

In the above technical solution, the thermosetting resin composition may further include a co-curing agent component (e) such as an amine compound, an amide compound, an acid anhydride compound, a phenol compound, or a cyanate ester. Specifically, the amine-based curing agent may be diaminodiphenylmethane, diaminodiphenylsulfone, diethylenetriamine, dicarboxyphthalimide, imidazole, or the like; the amide compound may be dicyandiamide, low molecular polyamide, or the like; the acid anhydride compound may be phthalic anhydride, trimellitic anhydride, pyromellitic dianhydride, maleic anhydride, hydrogenated phthalic anhydride, nadic anhydride, or the like; the phenolic compound may be a phosphorus-containing phenol resin, a nitrogen-containing phenol resin, a bisphenol a phenol resin, a phenol resin, a naphthol phenol resin, a biphenyl-modified naphthol resin, a dicyclopentadiene phenol addition-type resin, a phenol aralkyl resin, a naphthol aralkyl resin, a trimethylolmethane resin, a benzoxazine resin, or the like. The co-curing agent is preferably an acid anhydride curing agent or a cyanate curing agent. The cyanate resin refers to a compound containing cyanate groups in the structure, and can be one or more of bisphenol A type cyanate resin, bisphenol A cyanate resin, bisphenol M cyanate resin, dicyclopentadiene type cyanate resin, o-methyl novolac type epoxy resin, phenol type cyanate resin and polyphenyl ether modified cyanate resin. Preferably, the cyanate ester resin of the component (e) is added in a proportion of 10 to 200 parts by weight. The addition of an appropriate amount of the cyanate ester resin of component (e) can further optimize the heat resistance, adhesion and dielectric properties of the resin system, but too much addition results in a decrease in the wet heat resistance of the resin system.

In the technical scheme, the curing agent is also included, and the curing agent is an amine compound, an amide compound, an anhydride compound, a phenol compound or cyanate ester.

On the basis of the technical scheme, the thermosetting resin composition can also comprise 1-80 parts by weight of a flame retardant (f). The flame retardant may be a bromine-based flame retardant, a phosphorus-based flame retardant, a nitrogen-based flame retardant, an organosilicon flame retardant, an organic metal salt flame retardant, an inorganic flame retardant, or the like. Wherein the bromine flame retardant can be decabromodiphenyl ether, decabromodiphenyl ethane, brominated styrene or tetrabromophthalimide. The phosphorus-containing flame retardant may be an inorganic phosphorus, a phosphate compound, a phosphonic acid compound, a phosphinic acid compound, a phosphine oxide compound, an organic phosphorus-containing compound such as 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 10- (2, 5-dihydroxyphenyl) -9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 10-phenyl-9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, tris (2, 6-dimethylphenyl) phosphine, phosphazene, or the like. The nitrogen-based flame retardant may be a triazine compound, a cyanuric acid compound, an isocyanic acid compound, phenothiazine, or the like. The organic silicon flame retardant can be organic silicon oil, organic silicon rubber, organic silicon resin and the like. The organometallic flame retardant may be ferrocene, acetylacetone metal complexes, organometallic carbonyl compounds, and the like. The inorganic flame retardant may be aluminum hydroxide, magnesium hydroxide, aluminum oxide, barium oxide, or the like. The flame retardant to be added may be chosen according to the specific application of the laminate, and halogen-demanding applications, preferably non-halogen flame retardants, such as phosphorus-or nitrogen-containing flame retardants. Preferably, when a phosphorus-containing flame retardant is selected, nitrogen and phosphorus are formed to be cooperatively flame-retardant with nitrogen elements of maleimide ester in the technical scheme, so that the flame-retardant efficiency is improved. Preferably, the amount of the flame retardant added to the thermosetting resin composition is 5 to 50 parts by weight.

On the basis of the technical scheme, the thermosetting resin composition can also comprise a component (g) filler, and the addition amount of the filler is 1-80% of that of the solid resin component. The inorganic filler is selected from one or more of crystalline silica, fused silica, spherical silica, alumina, aluminum hydroxide, aluminum nitride, boron nitride, titanium dioxide, strontium titanate, barium sulfate, talcum powder, calcium silicate, calcium carbonate, mica, polytetrafluoroethylene and graphene filler.

One or more additives such as a toughening agent, a silane coupling agent, a pigment, an emulsifier, a dispersant, an antioxidant, an antistatic agent, a heat stabilizer, an ultraviolet absorber, a colorant, and a lubricant may be added to the thermosetting resin composition according to the actual conditions.

The thermosetting resin composition can be used for producing prepregs, laminates, printed circuit boards, semiconductor sealing materials, adhesive films for lamination, adhesives, resin casting materials, conductive pastes and the like.

The invention also discloses a prepreg prepared from the resin composition, the resin composition is dissolved by a solvent to prepare a glue solution, then the reinforcing material is soaked in the glue solution, and the soaked reinforcing material is heated and dried to obtain the prepreg.

The preparation of the glue solution preferably comprises the steps of firstly pre-polymerizing the unsaturated polyester active ester modified by the vinyl cross-linking agent of the component (b) under certain conditions, and then adding the pre-polymerized unsaturated polyester active ester modified by the vinyl cross-linking agent into the composition to be mixed to prepare the glue solution. After prepolymerization, the volatilization of vinyl monomers in the process of manufacturing the prepreg can be reduced.

When the composition contains the component (d) selected from one or more of hydrocarbon resin, vinyl-modified bismaleimide, vinyl-modified polyphenylene ether, vinyl-modified benzoxazine resin, cyanate resin (polyphenylene ether-modified cyanate resin), vinyl-modified phenol resin (vinyl-modified maleimide-based phenol resin, vinyl-modified phenol resin, dicyclopentadiene-vinylbenzyl phenyl ether), it is preferable to mix the component (b) and the component (d) together and perform prepolymerization.

The solvent is selected from one or more of acetone, butanone, toluene, methyl isobutyl ketone, N, N-dimethylformamide, N, N-dimethylacetamide, ethylene glycol methyl ether, propylene glycol methyl ether and propylene glycol methyl ether acetate. The reinforcing material can adopt natural fibers, organic synthetic fibers, organic fabrics or inorganic fabrics.

The invention also discloses a laminated board, wherein a metal foil is coated on one side or both sides of one prepreg, or at least 2 prepregs are stacked, then the metal foil is coated on one side or both sides of the prepreg, and hot press forming is carried out, so that the laminated board can be obtained.

The number of prepregs is determined according to the desired thickness of the laminate, and one or more prepregs may be used. The metal foil may be a copper foil or an aluminum foil, and the thickness thereof is not particularly limited.

Due to the application of the technical scheme, compared with the prior art, the invention has the following advantages:

1. the invention develops a novel unsaturated polyester active ester resin modified by an alkene crosslinking agent, which has a structure that not only has reactive unsaturated double bonds, but also has active ester groups capable of carrying out curing reaction with epoxy resin, and the whole molecular chain has more reaction functional groups, so that the crosslinking density after curing and crosslinking is high, and a resin system has better heat resistance and mechanical strength after curing;

2. the invention develops a novel unsaturated polyester active ester resin modified by an alkene crosslinking agent, the special structure of the unsaturated polyester active ester effectively combines an active ester curing epoxy resin system and a hydrocarbon resin curing system in a chemical bond form, and effectively combines the excellent performance of the active ester curing epoxy system and the excellent performance of the hydrocarbon resin, the active ester curing epoxy system endows the resin system with better low shrinkage and bonding performance, the peeling strength between a copper foil layer and a resin layer of a laminated board is improved, the dielectric performance of the resin system is not influenced, and the hydrocarbon resin curing system endows the material with very good dielectric performance and toughness;

3. experiments show that the resin composition disclosed by the invention has excellent dielectric property, heat resistance, strength, rigidity and flexibility after being cured, is high in peel strength, low in water absorption and small in heat shrinkage rate, and can be applied to high-speed and high-frequency printed circuit boards.

Detailed Description

The invention is further described below with reference to the following examples:

synthesis examples 1 to 2 and comparative examples 1 to 2 are resin synthesis, examples 1 to 4 are prepolymer synthesis in the present invention, and examples 5 to 9 and comparative examples 3 to 4 are preparation of the thermosetting resin composition provided by the present invention and evaluation of physical properties.

Synthesis example 1

Putting 1000g of tetrahydrofuran, 100g of dicyclohexylcarbodiimide, 58.8g of maleic anhydride and 228g of bisphenol A into a three-necked reaction bottle, fully dissolving, then putting into the three-necked reaction bottle, fully mixing, then adding a catalytic amount of 4-dimethylaminopyridine under stirring, reacting for 5 hours at room temperature, and then separating and purifying a product to obtain an active ester resin A-1, wherein the equivalent weight of hydroxyl functional groups in the active ester resin (A-1) is 690 g/equivalent in terms of the input ratio, the equivalent weight of ester functional groups is 230 g/equivalent in terms of the input ratio, and the equivalent weight of unsaturated double bond functional groups is 460 g/equivalent;

putting 1000g of methyl isobutyl ketone solvent into a flask provided with a thermometer, a dropping funnel, a condenser pipe, a shunt pipe and a stirrer, then putting 1276 g of active ester resin A into the flask, and fully dissolving; introducing nitrogen into the reaction system under reduced pressure, and controlling the temperature of the system to be below 65 ℃; then, 70g of benzoyl chloride is added, 210g of 20% sodium hydroxide solution is dropwise added into the system for 3 hours, and after the dropwise addition is finished, the reaction is maintained at 65 ℃ for 3 hours; after the reaction is finished, separating and removing a water layer; then adding water into the system, stirring and cleaning, and separating to remove a water layer; repeating the cleaning operation for 3-5 times; then, methyl isobutyl ketone was removed by vacuum-evacuation and reduced pressure to obtain an active ester resin (B-1) in which the equivalent of ester group function was 529 g/equivalent in charge ratio calculated as 198 g/equivalent of unsaturated double bond function.

Synthesis example 2

Putting 1000g of tetrahydrofuran, 100g of dicyclohexylcarbodiimide, 58.8g of maleic anhydride and 160g of 2, 7-dihydroxynaphthalene into a three-necked reaction bottle, fully dissolving the materials, then putting the materials into the three-necked reaction bottle, fully mixing the materials, adding a catalytic amount of 4-dimethylaminopyridine into the mixture under stirring, reacting the mixture at room temperature for 5 hours, and separating and purifying the product to obtain an active ester resin (A-2), wherein the equivalent weight of a hydroxyl functional group in the active ester resin (A-2) is 520 g/equivalent calculated by the input ratio, the equivalent weight of an ester functional group is 173 g/equivalent calculated by the input ratio, and the equivalent weight of an unsaturated double bond functional group is 347 g/equivalent;

putting 1000g of methyl isobutyl ketone solvent into a flask provided with a thermometer, a dropping funnel, a condenser pipe, a shunt pipe and a stirrer, then putting 2208 g of resin A into the flask, and fully dissolving; introducing nitrogen into the reaction system under reduced pressure, and controlling the temperature of the system to be below 65 ℃; then, 70g of benzoyl chloride is added, 210g of 20% sodium hydroxide solution is dropwise added into the system for 3 hours, and after the dropwise addition is finished, the reaction is maintained at 65 ℃ for 3 hours; after the reaction is finished, separating and removing a water layer; then adding water into the system, stirring and cleaning, and separating to remove a water layer; repeating the cleaning operation for 3-5 times; then, methyl isobutyl ketone was removed by vacuum-evacuation and reduced pressure to obtain an active ester resin (B-2) in which the equivalent of ester group function was 156 g/equivalent in charge ratio and the equivalent of unsaturated double bond function was 416 g/equivalent.

Comparative example 1

Putting 228g of bisphenol A and 1000g of methyl isobutyl ketone solvent into a flask provided with a thermometer, a fractionator, a condenser and a stirrer, fully mixing and dissolving the mixture in the flask, introducing nitrogen into a reaction system under reduced pressure, and controlling the temperature of the system to be 65 ℃; then, 121.8g of terephthaloyl chloride is added, 210g of 20% sodium hydroxide solution is dropwise added into the system for 3 hours, and after the dropwise addition is finished, the reaction is maintained at 65 ℃ for 3 hours; after the reaction is finished, separating and removing a water layer; then adding water into the system, stirring and cleaning, and separating to remove a water layer; repeating the cleaning operation for 3-5 times; then, the methyl isobutyl ketone was removed by vacuum-pumping and reducing the pressure to obtain an active ester resin (A-3) in which the equivalent of the hydroxyl functional group was 765 g/equivalent in terms of the charge ratio and the equivalent of the ester functional group was 255 g/equivalent in terms of the charge ratio;

putting 255g of active ester resin (A-3) and 1000g of methyl isobutyl ketone solvent into a flask provided with a thermometer, a fractionator, a condenser and a stirrer, fully mixing and dissolving, introducing nitrogen into a reaction system under reduced pressure, and controlling the temperature of the system at 65 ℃; then, 70g of benzoyl chloride is added, 210g of 20% sodium hydroxide solution is dropwise added into the system for 3 hours, and after the dropwise addition is finished, the reaction is maintained at 65 ℃ for 3 hours; after the reaction is finished, separating and removing a water layer; then adding water into the system, stirring and cleaning, and separating to remove a water layer; repeating the cleaning operation for 3-5 times; then, methyl isobutyl ketone was removed by vacuum-evacuation and reduced pressure to obtain an active ester resin (B-3) having a functional group equivalent of about 217 g/equivalent in terms of charge ratio.

Comparative example 2

With reference to the method of comparative example 1, active ester resin (A-3) was obtained, 255g of active ester resin (A-3) and 1000g of methyl isobutyl ketone solvent were charged into a flask equipped with a thermometer, a fractionator, a condenser and a stirrer, and dissolved in the flask by thoroughly mixing, and nitrogen gas was introduced into the reaction system under reduced pressure while controlling the system temperature at 65 ℃; then, 45.0g of acryloyl chloride was added, and then 210g of 20% sodium hydroxide solution was added dropwise to the system over 3 hours, and after the dropwise addition was completed, the reaction was maintained at 65 ℃ for 3 hours; after the reaction is finished, separating and removing a water layer; then adding water into the system, stirring and cleaning, and separating to remove a water layer; repeating the cleaning operation for 3-5 times; then, methyl isobutyl ketone was removed by vacuum-evacuation and reduced pressure to obtain an active ester resin (B-4) having a functional group equivalent of about 205 g/eq depending on the charge ratio.

Examples 1 to 9 and comparative examples 3 to 5

Example 1

In a flask equipped with a thermometer, a fractionator, a condenser and a stirrer, 500g of butanone is added, 120g of B-1 resin, 20g of styrene and 3g of tert-butyl peroxybenzoate are added, the mixture is fully stirred and dissolved, nitrogen is introduced into the reaction system under reduced pressure, the temperature of the system is controlled at 85 ℃ for reaction for 2 hours, and then the reaction system is naturally cooled to room temperature, so that prepolymer C-1 is prepared for standby.

Example 2

In a flask equipped with a thermometer, a fractionator, a condenser and a stirrer, 500g of butanone was put in, 120g of B-1 resin, 20g of styrene, 10g of bismaleimide resin and 3g of t-butyl peroxybenzoate were added, and after sufficient stirring and dissolution, nitrogen gas was introduced under reduced pressure into the reaction system, and the system temperature was controlled at 85 ℃ to react for 2 hours, and then naturally cooled to room temperature to prepare a prepolymer C-2 for use.

Example 3

In a flask equipped with a thermometer, a fractionator, a condenser tube and a stirrer, 500g of butanone is added, 120g of B-1 resin, 20g of styrene, 20g of hydrocarbon resin and 3g of tert-butyl peroxybenzoate are added, after full stirring and dissolution, nitrogen is introduced into the reaction system under reduced pressure, the temperature of the system is controlled at 85 ℃ for reaction for 2 hours, and then the reaction system is naturally cooled to room temperature, thus obtaining prepolymer C-3 for later use.

Example 4

200g of butanone is put into a flask provided with a thermometer, a fractionator, a condenser tube and a stirrer, 50g of B-2 resin, 10g of styrene and 1g of tert-butyl peroxybenzoate are added, the mixture is fully stirred and dissolved, nitrogen is introduced into a reaction system under reduced pressure, the temperature of the system is controlled within 85 ℃ for reaction for 1 hour, and then the reaction system is naturally cooled to room temperature to prepare prepolymer C-4 for later use.

Then, other components were added in the proportions shown in table 1, the components were mixed uniformly to prepare a 60% resin solution, the resin solution was impregnated with a glass fiber cloth as a reinforcing material, the impregnated glass fiber cloth was heated in an oven at 175 ℃ for 2 to 10 minutes to prepare a prepreg for a printed circuit, a laminate was prepared under the following conditions, and the dielectric properties, heat resistance, adhesion properties, toughness, strength and the like of the laminate were evaluated by the following methods, and the results are shown in table 1.

Referring to the formulations of examples 5 to 9 and comparative examples 3 to 5 in table 1, firstly, the unsaturated polyester active ester, the vinyl crosslinking agent and the initiator in example 6 are pre-polymerized into a prepolymer according to the method of example 1, the unsaturated polyester active ester, the vinyl crosslinking agent and the initiator in example 7 are pre-polymerized into a prepolymer according to the method of example 2, the unsaturated polyester active ester, the vinyl crosslinking agent and the initiator in example 8 are pre-polymerized into a prepolymer according to the method of example 3, and the unsaturated polyester active ester, the vinyl crosslinking agent, the initiator and the hydrocarbon resin in example 9 are pre-polymerized into a prepolymer according to the method of example 4; example 5 and comparative examples 3 to 5 were prepared by ordinary physical blending.

< conditions for producing laminate >

Base material: common electronic grade 2116 glass fiber cloth;

layer number: 8;

thickness of the formed plate: 1.0 mm;

preimpregnation and semi-solidification conditions: 175 ℃/5 min;

curing conditions are as follows: 180 ℃/120 min.

< measurement of dielectric constant and dielectric loss tangent > dielectric constant at 1GHz, dielectric loss tangent were measured by the IPC-TM-6502.5.5.9 using the plate method: the dielectric dissipation factor at 1GHz was measured by the plate method according to IPC-TM-6502.5.5.9.

< Peel Strength > the adhesive properties of the thermosetting resin composition were characterized using the peel strength of the laminate, and the peel strength of the metal covering was tested according to the "after thermal stress" experimental conditions in the IPC-TM-6502.8 method.

< Water absorption > measurement was carried out according to the method of IPC-TM-6502.6.2.1.

< thermal stratification time T-288> was measured according to the IPC-TM-6502.4.24.1 method.

< glass transition temperature > was measured using the DMA method.

The maximum stress that the material can withstand when it breaks under a bending load or reaches a predetermined bending moment, which is the maximum normal stress in bending in MPa (megapascal), is measured using a universal material testing machine.

TABLE 1

Footnotes of table 1:

epoxy resin: DIC HP-7200H, epoxy equivalent 278 g/eq;

b-1: synthesis of the unsaturated polyester active ester (B-1) obtained in example 1;

b-2: synthesis of the unsaturated polyester active ester (B-2) obtained in example 2;

b-3: the unsaturated polyester active ester (B-3) obtained in comparative example 1;

b-4: the unsaturated polyester active ester (B-4) obtained in comparative example 2;

ethylenic crosslinking agent-1: styrene;

ethylenic crosslinking agent-2: bismaleimide resin;

initiator: tert-butyl peroxybenzoate;

accelerator (b): dimethylaminopyridine;

hydrocarbon resin: styrene-butadiene resin (sartomedr, Ricon 100);

co-curing agent: styrene-maleic anhydride copolymer, self-made;

filling: spherical silicon micro powder.

From the results of table 1, it can be seen that: in examples 5 to 9, the heat resistance and the flexural strength were significantly improved and the dielectric properties were significantly improved as compared with those of comparative examples 3 and 5 in which the active ester was used for curing. The heat resistance, peel strength and flexural strength of the cured products of examples 5 to 9 were significantly improved as compared with those of the cured product of comparative example 4. In example 7, the heat resistance, peel strength and flexural strength were all improved significantly as compared with example 6. In example 8, the dielectric constant Dk and the dielectric loss tangent Df were both significantly reduced as compared with example 6.

In conclusion, the thermosetting resin composition and the prepreg and the laminated board for the printed circuit prepared by the thermosetting resin composition have the characteristics of excellent dielectric property, heat resistance, bending strength, high peel strength, low water absorption, excellent processing technology performance and the like.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A thermosetting resin composition characterized by comprising, in parts by weight:

(a) epoxy resin: 100 parts of (A);

(c) accelerator (b): 0.05-4 parts;

the unsaturated polyester active ester modified by the vinyl crosslinking agent is a prepolymer prepared by mixing a vinyl monomer, an unsaturated polyester active ester and an initiator, and the unsaturated polyester active ester has the following structural formula:

wherein:

the value of n is 0.5-10;

X₁selected from-CH ═ CH-),

And must contain-CH ═ CH-;

Y₁one or more selected from the following groups:

naphthylene ether in which Z₁Is isopropylidene, cyclopentadienyl, sulfuryl, methylene or oxygen atom, Rx is hydrogen atom or alkyl with carbon atom number less than or equal to 5;

ra is a hydrogen atom, benzoyl, substituted benzoyl or alkanoyl;

rb is a hydrogen atom, phenyl or substituted phenyl;

the vinyl monomer is one or more selected from styrene, substituted styrene, methyl acrylate, substituted methyl acrylate and maleimide resin, and the maleimide resin is required to be contained.

2. The thermosetting resin composition according to claim 1, characterized in that: the epoxy resin is selected from one or more of bisphenol A epoxy resin, bisphenol F epoxy resin, phosphorus-containing epoxy resin, nitrogen-containing epoxy resin, bisphenol A novolac epoxy resin, phenol novolac epoxy resin, cresol novolac epoxy resin, triphenylmethane epoxy resin, tetraphenylethane epoxy resin, biphenyl type epoxy resin, naphthalene ring type epoxy resin, dicyclopentadiene type epoxy resin, aralkyl novolac epoxy resin, polyphenyl ether modified epoxy resin and alicyclic epoxy resin.

3. The thermosetting resin composition according to claim 1, characterized in that: the promoter is selected from one or more of the following substances: dimethylaminopyridine, tertiary amines and their salts, imidazoles, organometallic salts, triphenylphosphine and its phosphonium salts.

4. The thermosetting resin composition claimed in claim 1, wherein: the ratio of the alkene monomer to the unsaturated polyester active ester is 0.05: 1-5: 1 in terms of the functional equivalent of the unsaturated double bond.

5. The thermosetting resin composition according to claim 1, characterized in that: the composite material also comprises a component (d), wherein the component (d) is one or more selected from hydrocarbon resin, vinyl modified bismaleimide, vinyl modified polyphenyl ether, vinyl modified benzoxazine resin, vinyl modified phenolic resin and single-component polyurethane resin.

6. The thermosetting resin composition according to claim 5, characterized in that: the vinyl modified phenolic resin is vinyl modified maleimide phenolic resin or vinyl modified linear phenolic resin.

7. The thermosetting resin composition according to claim 1, characterized in that: the curing agent is amine compound, amide compound, anhydride compound, phenolic compound or cyanate.

8. A prepreg produced using the resin composition according to claim 1, characterized in that: dissolving the resin composition with a solvent to prepare a glue solution, then soaking the reinforcing material in the glue solution, and heating and drying the soaked reinforcing material to obtain the prepreg.

9. A laminate, characterized by: the laminate can be obtained by coating a metal foil on one side or both sides of a prepreg according to claim 8, or by laminating at least 2 prepregs according to claim 8, coating a metal foil on one side or both sides, and hot press forming.