Phosphorus-containing benzoxazine compounds having a triazine structure and epoxy resin compositions

Abstract

The present application belongs to the technical field of high polymer materials, and particularly relates to a phosphorus-containing benzoxazine compound with a triazine structure and an epoxy resin composition. The phosphorus-containing benzoxazine compound with a triazine structure of the present application is ring-opened under the action of heating and a catalyst and participates in the curing of an epoxy resin; meanwhile, the flame retardancy of a polymer can be greatly improved; in addition, the compound has no active functional groups such as amino groups, tertiary amine groups and phenolic hydroxyl groups before ring-opening under heating, has good latency for an epoxy resin and is conducive to the long-time storage of an epoxy resin composition. The epoxy resin composition obtained by mixing the phosphorus-containing benzoxazine compound with a triazine structure, an epoxy resin, a co-curing agent and a curing accelerator in a certain ratio can be widely used in scenes such as plastic encapsulation materials, prepreg materials, laminated boards, packaging substrates and printed circuit boards.

Description

Technical Field

[0001] This invention belongs to the field of polymer materials technology, specifically relating to phosphorus-based benzoxazine compounds containing triazine structures and epoxy resin compositions. Background Technology

[0002] Epoxy resin is a widely used polymer material with broad applications in composite materials, electronic packaging, and other fields, such as molding compounds, laminates, packaging substrates, printed circuit boards, carbon fiber prepregs, and glass fiber composites. However, while epoxy resin possesses excellent mechanical and adhesive properties, its flame retardant properties are relatively poor. Furthermore, bromine-containing flame-retardant epoxy resins release harmful substances upon combustion, posing environmental pollution problems. In recent years, halogen-free flame retardants have received increasing attention. For example, phosphorus-containing and nitrogen-containing flame retardants have garnered significant interest. For instance, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), diphenylphosphine oxide (DPPO), and melamine all exhibit good flame-retardant effects, but how to incorporate these flame retardants into epoxy resin systems remains a key focus. Zhou Hong et al. reported a benzo-melamine structured nitrogen-phosphorus high-efficiency flame retardant (patent 201910828940.2), demonstrating excellent flame-retardant performance. However, these flame retardants contain phenolic hydroxyl groups and secondary amine structures, which may affect the storage of the prepared epoxy resin composition and shorten its shelf life.

[0003]

[0004] Therefore, reactive flame retardants need to possess a certain degree of latency to avoid affecting the shelf life of epoxy resin compositions. Most reactive flame retardants participate in the curing of epoxy resins; therefore, designing and preparing flame retardants with both latency and the ability to participate in epoxy resin curing is a challenging problem.

[0005] Benzoxazine is a resin that can be polymerized into a thermosetting resin through a thermally activated ring-opening reaction. Simultaneously, the polymer formed after ring-opening of benzoxazine can participate in the curing of epoxy resins and can be used as a curing agent for epoxy resins. Cured benzoxazine yields thermosetting resins with low water absorption, excellent electrical properties, and low surface energy, and its cured product also exhibits good flame retardant properties. However, its flame retardancy is not yet sufficient to meet the requirements of various applications. Summary of the Invention

[0006] The purpose of this invention is to provide a phosphorus-based benzoxazine compound containing a triazine structure, which has low water content, excellent electrical properties, and excellent flame retardant properties, as well as an epoxy resin composition formulated from the compound.

[0007] This invention first provides a triazine-containing phosphorus-based benzoxazine compound, which exhibits excellent flame retardant properties and good latency in epoxy resin compositions. This triazine-containing phosphorus-based benzoxazine compound can undergo ring-opening under heating and catalytic action, participating in the curing of epoxy resins. Simultaneously, the triazine and phosphorus-containing structures significantly enhance the flame retardancy of the polymer. Furthermore, before ring-opening upon heating, this compound lacks active functional groups such as amino, tertiary amine, and phenolic hydroxyl groups, thus exhibiting good latency in epoxy resins.

[0008] The phosphorus-based benzoxazine compound containing a triazine structure has the structure shown in formula (1):

[0009]

[0010] Where X is selected from the following structures;

[0011]

[0012] Y is selected from: hydrogen, C1-C6 alkyl, C2-C6 olefin, CF3, phenyl, substituted phenyl (such as methyl, ethyl-substituted phenyl), halogen, phenoxy, C3-C7 cycloalkyl.

[0013] R is selected from: hydrogen, hydroxyl, allyl, C1-C6 alkyl, C1-C6 alkoxy, CF3, OCF3, phenyl, halogen, phenoxy, C3-C7 cycloalkyl;

[0014] n represents the number of R substituents, which ranges from 1 to 3.

[0015] The typical structural formulas of the structure shown in equation (1) are:

[0016]

[0017]

[0018] This invention also provides a method for preparing a phosphorus-based benzoxazine compound (structural formula 1) containing a triazine structure, which consists of two stages:

[0019] Stage 1: React the following compounds together:

[0020] Compound A.

[0021] To form the structure of the following formula (6):

[0022]

[0023] In formula (5), L is selected from: hydrogen, C1-C6 alkyl, C2-C6 olefin, CF3, phenyl, substituted phenyl (such as methyl, ethyl substituted phenyl), halogen, phenoxy, C3-C7 cycloalkyl, amino.

[0024] The typical structure of equation (5) is as follows:

[0025]

[0026] Compound A is selected from:

[0027] In formula (6), the Z1 group is selected from: hydrogen, C1-C6 alkyl, C1-C6 alkoxy, CF3, phenyl, halogen, phenoxy, C3-C7 cycloalkyl, or

[0028] In formula (6), the Z2 group is selected from:

[0029] In formulas (4) and (6), R is selected from: hydrogen, hydroxyl, allyl, C1-C6 alkyl, C1-C6 alkoxy, CF3, OCF3, phenyl, halogen, phenoxy, C3-C7 cycloalkyl;

[0030] n represents the number of R substituents, which ranges from 1 to 3.

[0031] Phase 2:

[0032] The compound of formula (6) is reacted with an aldehyde-containing compound to form the compound shown in structure (1). The aldehyde-containing substance is selected from: formaldehyde, formaldehyde aqueous solution, trioxymethylene, and paraformaldehyde.

[0033] In stage 1, the reaction conditions are as follows: the ratio of formulas (4), (5) and structural formula A is between 1:1.2:1 and 1:2:1. The reaction solvent is selected from one or more of the following solvents: methanol, ethanol, water, dichloromethane, trichloromethane, toluene, xylene, tetrahydrofuran, diethyl ether, methyl tert-butyl ether, methyl isobutyl ketone, acetonitrile, nitrobenzene, chlorobenzene, o-dichlorobenzene, N,N-dimethylformamide, N,N-diethylacetamide, dioxane, sulfolane, dimethylacetamide, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, 1,3-dimethylpropylene urea, N-methylpyrrolidone, N,N'-dimethylethylidene urea, dimethyl sulfoxide. The reaction temperature is between 0℃ and 120℃. The reaction time is between 30 minutes and 48 hours. After the reaction is complete, the product is added dropwise to methanol or acetone and water as a precipitant to precipitate it, and then washed with deionized water to obtain the product of the first stage.

[0034] In stage 2, the reaction conditions are as follows: The product of stage 1 is mixed with aldehydes in a ratio between 1:1 and 1:10. The aldehydes are selected from formaldehyde, formaldehyde aqueous solution, paraformaldehyde, and paraformaldehyde. The reaction solvent is selected from one or more of the following solvents: water, chloroform, toluene, xylene, tetrahydrofuran, diethyl ether, methyl tert-butyl ether, methyl isobutyl ketone, acetonitrile, nitrobenzene, chlorobenzene, N,N-dimethylformamide, N,N-diethylacetamide, dioxane, sulfolane, dimethylacetamide, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, 1,3-dimethylpropylene urea, N-methylpyrrolidone, N,N'-dimethylethylidene urea, and dimethyl sulfoxide. The reaction temperature is between 0℃ and 120℃. The reaction time is between 30 minutes and 48 hours. After the reaction is complete, the product is added dropwise to methanol or acetone and water as a precipitant to precipitate it, and then washed with deionized water to obtain the product of the second stage, namely the phosphorus-based triazine-containing benzoxazine described in this invention.

[0035] Alternatively, after the first stage reaction is completed, an aldehyde can be directly added to the solution system from the first stage to initiate the second stage reaction. The aldehyde is selected from formaldehyde, formaldehyde aqueous solution, trioxymethylene, and paraformaldehyde. The reaction temperature is between 0℃ and 120℃. The reaction time is between 30 minutes and 48 hours. After the reaction is complete, the product is precipitated dropwise in methanol or acetone / water precipitant, and then washed with deionized water to obtain the product of the second stage, namely the phosphorus-based triazine-containing benzoxazine described in this invention.

[0036] This invention relates to a triazine-structured phosphorus-based benzoxazine compound, primarily used for preparing thermosetting epoxy resin compositions. The thermosetting epoxy resin composition mainly comprises epoxy resin, a triazine-structured phosphorus-based benzoxazine compound (containing a phosphorus-active ester flame retardant), a co-curing agent, and a curing accelerator. Based on a total mass of 100 parts, the epoxy resin accounts for 15-60 parts, the phosphorus-active ester flame retardant accounts for 5-60 parts, the co-curing agent accounts for 0-60 parts (preferably 1-60 parts), and the curing accelerator accounts for 0.3-5 parts. Wherein:

[0037] The epoxy resin is selected from one or more of the following epoxy resins: bisphenol A type epoxy resin, bisphenol B type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, o-cresol formaldehyde type epoxy resin, phenolic type epoxy resin, hydrogenated bisphenol A type epoxy resin, tetrabromobisphenol A type epoxy resin, dicyclopentadiene phenol epoxy resin, biphenyl type epoxy resin, binatidine type epoxy resin, naphthyldiphenol type epoxy resin, diaminodiphenylmethane tetraglycidyl epoxy resin, etc.

[0038] The co-curing agent is selected from one or more of the following: phenolic resin, phenolic resin active ester, dicyclopentadiene type active ester, polyester resin, amino resin, benzoxazine resin, liquid polyurethane, polysulfide rubber, o-cresol resin, dicyclopentadiene phenol resin, acid anhydride curing agent, amine curing agent, acyl hydrazine curing agent, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl sulfone, dicyandiamide, m-phenylenediamine, p-phenylenediamine, adipate dihydrazine, phthalic anhydride, tetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylnadia anhydride, pyromellitic anhydride, and benzophenone tetracarboxylic anhydride.

[0039] The curing accelerator may be selected from one or more of the following: triphenylphosphine, 4-dimethylaminopyridine, 2,4,5-triphenylimidazolium, tetraphenylphosphine bromide, N-methylimidazolium, imidazolium, benzyltriphenylphosphine bromide, ethyltriphenylphosphine acetate, 1-cyanoethyl-2-methylimidazolium, 2-methylimidazolium, 2-ethyl-4-methylimidazolium, 1-cyanoethyl-2-ethyl-4-methylimidazolium, 2,4,6-tris(dimethylaminomethyl)phenol (DMP-30).

[0040] In addition, thermosetting resin compositions may also contain fillers, release agents, leveling agents, reactive diluents, and solvents.

[0041] The thermosetting epoxy resin composition of the present invention can be applied to composite materials, electronic packaging materials and other fields.

[0042] Specifically, the composition is compounded and cured with one or more of polytetrafluoroethylene microspheres, nano-silica, micron-sized silica, boron nitride, magnesium oxide, chopped glass fiber, glass fiber cloth, and high-performance polymer fiber, and can be used as a molding compound, substrate, carrier, printed circuit board, and laminate manufacturing resin in the field of electronic packaging.

[0043] Thermosetting epoxy resin compositions were cured by programmed temperature rise, and the resulting materials were tested for flame retardancy. The tests showed that the materials exhibited excellent flame retardant properties, with limiting oxygen indices all greater than 27%. Attached Figure Description

[0044] Figure 1 The NMR spectra of compound 1-1 and its intermediates are shown below. Detailed Implementation

[0045] The present invention will be further described below through examples.

[0046] Example 1

[0047] Compounds of formula 1-1 were synthesized using a two-stage method.

[0048]

[0049] Stage 1 involved the synthesis of the intermediate. 2.44 g (20 mmol) of salicylaldehyde, 1.87 g (10 mmol) of benzomelamine, and 4.33 g (20 mmol) of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) were added to a reaction flask containing 50 mL of DMF. The reaction was carried out at 90 °C under nitrogen protection for 12 h. After the reaction was complete, the reaction solution was poured into deionized water, resulting in the precipitation of a white precipitate. The system was then filtered, and the precipitate was washed twice with deionized water. Finally, the precipitate was dried to obtain 6.78 g of the final white powder solid intermediate product (yield 82%).

[0050] Stage 2 was the synthesis of the final benzoxazine product. 4.14 g (0.005 mol) of the white solid intermediate obtained in Stage 1 was added to a reaction flask containing 50 mL of toluene. 1.125 g of a 40% formaldehyde aqueous solution (containing 0.45 g, 15 mmol of formaldehyde) was added to the reaction flask. The temperature was raised to reflux temperature and stirred continuously for 12 hours. After the reaction was complete, the solution was washed with deionized water, separated, dried, and the solvent was removed using a rotary evaporator. The product was then dried in a vacuum oven at 80°C for 12 hours to obtain 3.791 g of the white solid product (yield 89%).

[0051] Example 2,

[0052] Compounds of formula 1-2 were synthesized using a two-stage method.

[0053]

[0054] Stage 1 involved the synthesis of the intermediate. 2.44 g (20 mmol) of salicylaldehyde, 1.25 g (10 mmol) of 6-methyl-1,3,5-triazine-2,4-diamine, and 4.33 g (20 mmol) of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) were added to a reaction flask containing 50 mL of DMF. The reaction was carried out at 90 °C under nitrogen protection for 12 h. After the reaction was complete, the reaction solution was poured into deionized water, resulting in the precipitation of a white precipitate. The system was then filtered, and the precipitate was washed twice with deionized water. Finally, the precipitate was dried to obtain the final white solid intermediate product (6.59 g, 86%).

[0055] Phase 2

[0056] Stage 2 was the synthesis of the final benzoxazine product. 3.83 g of the white solid intermediate obtained in Stage 1 was added to a reaction flask containing 50 mL of toluene. 1.125 g of a 40% formaldehyde aqueous solution (containing 0.45 g of formaldehyde, 15 mmol) was added to the reaction flask. The temperature was raised to reflux temperature and stirred continuously for 12 hours. After the reaction was complete, the solution was washed with deionized water, separated, dried, and the solvent was removed using a rotary evaporator. The solution was then dried in a vacuum oven at 80°C for 12 hours. A white solid product (3.63 g, 92%) was obtained.

[0057] Example 3

[0058] Compounds with formulas 1-5 were synthesized using a two-stage method.

[0059]

[0060] Stage 1 involved the synthesis of the intermediate. 2.44 g (20 mmol) of salicylaldehyde, 1.87 g (10 mmol) of benzomelamine, and 4.05 g (20 mmol) of diphenylphosphine oxide (DPPO) were added to a reaction flask containing 50 mL of DMF. The reaction was carried out at 90 °C under nitrogen protection for 12 h. After the reaction was complete, the reaction solution was poured into deionized water, resulting in the precipitation of a white precipitate. The system was then filtered, and the precipitate was washed twice with deionized water. Finally, the precipitate was dried to obtain the final white solid intermediate product (6.08 g, 76%).

[0061] Stage 2 was the synthesis of the final benzoxazine product. 4.0 g of the white solid intermediate obtained in Stage 1 was added to a reaction flask containing 50 mL of toluene, and 0.45 g of paraformaldehyde powder was added to the flask. The temperature was raised to reflux temperature and stirred continuously for 12 hours. After the reaction was complete, the mixture was cooled to room temperature and washed with deionized water. After drying the liquid, the solvent was removed using a rotary evaporator, and the product was dried in a vacuum oven at 80°C for 12 hours. A white solid product (3.63 g, 88%) was obtained.

[0062] Example 4

[0063] Compounds with formulas 1-7 were synthesized using a two-stage method.

[0064]

[0065] Stage 1 involved the synthesis of the intermediate. 3.66 g (30 mmol) of salicylaldehyde, 1.26 g (10 mmol) of melamine, and 6.485 g (30 mmol) of DOPO were added to a reaction flask containing 50 mL of DMF. The reaction was carried out at 90 °C under nitrogen protection for 12 h. After the reaction was complete, the reaction solution was poured into deionized water, resulting in the precipitation of a white powder. The system was then filtered, and the precipitate was washed twice with deionized water. Finally, the precipitate was dried to obtain the final pale orange-yellow solid intermediate product (9.02 g, 83%).

[0066] Stage 2 was the synthesis of the final benzoxazine product. 5.44 g of the solid intermediate product obtained in Stage 1 was added to a reaction flask containing 50 mL of toluene, and 0.45 g of paraformaldehyde powder was added to the flask. The temperature was raised to reflux temperature and stirred continuously for 12 hours. After the reaction was complete, the mixture was cooled to room temperature and washed with deionized water. After drying the liquid, the solvent was removed using a rotary evaporator, and the product was dried in a vacuum oven at 80°C for 12 hours. A white solid product (5.11 g, 91%) was obtained.

[0067] Example 5

[0068] Compounds of formula 1-11 were synthesized using a two-stage method.

[0069]

[0070] Stage 1 involved the synthesis of the intermediate. 2.76 g (20 mmol) of 2,4-dihydroxybenzaldehyde, 1.87 g (10 mmol) of benzomelamine, and 4.324 g (20 mmol) of DOPO were added to a reaction flask containing 50 mL of DMF. The reaction was carried out at 90 °C under nitrogen protection for 12 h. After the reaction was complete, the reaction solution was poured into deionized water, resulting in the precipitation of a pink precipitate. The system was then filtered, and the precipitate was washed twice with deionized water. Finally, the precipitate was dried to obtain 6.70 g (78%) of the final light-colored solid intermediate product.

[0071] Stage 2 was the synthesis of the final benzoxazine product. 4.30 g (0.005 mol) of the solid intermediate product obtained in Stage 1 was added to a reaction flask containing 50 mL of toluene, and 0.45 g of paraformaldehyde powder was added to the flask. The temperature was raised to reflux temperature and stirred continuously for 12 hours. After the reaction was complete, the mixture was cooled to room temperature and washed three times with deionized water. After drying the liquid, the solvent was removed using a rotary evaporator, and the product was dried in a vacuum oven at 80°C for 12 hours. A light pink solid product (3.36 g, 76%) was obtained.

[0072] Example 6, Preparation of epoxy resin curing composition 1

[0073] Compound 1-1 (5 parts) was added to bisphenol A type epoxy resin (60 parts), methyl nadia acid anhydride (35 parts) was used as a co-curing agent, and DMAP (0.05 parts) was used as an accelerator to prepare epoxy composition 1. The epoxy was cured at 120°C for 2 hours, 160°C for 2 hours, and 200°C for 2 hours. After curing, the limiting oxygen index (LOI) was tested (test standard: ASTM D863-97), and the LOI was 30%.

[0074] Example 7, Preparation of epoxy resin curing composition 2

[0075] Compounds 1-2 (5 parts) were added to bisphenol A type epoxy resin (60 parts), and dicyandiamide (22 parts) and DMAP were used as an accelerator (0.05 parts) to prepare epoxy composition 2. The epoxy was cured at 120°C for 2 hours, 160°C for 2 hours, and 210°C for 2 hours. The limiting oxygen index (LOI) was tested (test standard: ASTM D863-97), and the LOI was 32%.

[0076] Example 8, Preparation of epoxy resin curing composition 3

[0077] Compounds 1-5 (3 parts) were added to dicyclopentadiene phenol epoxy resin (60 parts), acetic acid-functionalized o-cresol resin was used as a co-curing agent (28 parts), and DMAP was used as an accelerator (0.05 parts) to prepare epoxy composition 3. Curing was performed at 120℃ for 2 hours, 180℃ for 2 hours, and 200℃ for 2 hours. The limiting oxygen index (LOI) was tested (test standard: ASTM D863-97) and found to be 32%.

[0078] Example 9, Preparation of epoxy resin curing composition 4

[0079] Compounds 1-7 (13 parts) were added to dicyclopentadiene phenol epoxy resin (60 parts), o-cresyl formaldehyde resin as a co-curing agent (27 parts), and DMAP as an accelerator (0.05 parts) to prepare epoxy composition 4. Curing was performed at 120℃ for 2 hours, 160℃ for 2 hours, and 200℃ for 2 hours. The cured material was then subjected to a limiting oxygen index (LOI) test (test standard: ASTM D863-97), with a LOI of 33%.

[0080] Example 10: Preparation of epoxy resin curing composition 5

[0081] Compound 1-11 (42 parts) was added to dicyclopentadiene phenol epoxy resin (58 parts), and DMAP was used as an accelerator (0.05 parts) to prepare epoxy composition 5. The mixture was cured at 120°C for 2 hours, 150°C for 2 hours, and 210°C for 2 hours. The cured material was then subjected to a limiting oxygen index (LOI) test (test standard: ASTM D863-97), which showed an LOI of 37%.

Claims

1. A phosphorus-based benzoxazine compound containing a triazine structure, characterized in that, It has the structure shown in equation (1): Equation (1) Where X is selected from the following structures; Equation (2), Equation (3); Y is selected from: hydrogen, C1~C6 alkyl, C2~C6 olefin, CF3, phenyl, halogen, phenoxy, C3-C7 cycloalkyl. Equation (2) or Equation (3); R is selected from: hydrogen, hydroxyl, allyl, C1~C6 alkyl, C1~C6 alkoxy, CF3, OCF3, phenyl, halogen, phenoxy, C3-C7 cycloalkyl; n represents the number of R substituents, which ranges from 1 to 3.

2. The phosphorus-based benzoxazine compound containing a triazine structure according to claim 1, characterized in that, The structural formula shown in equation (1) is one of the following 1-1 to 1-12: 。 3. The method for preparing the triazine-containing phosphorus-based benzoxazine compound as described in claim 1, characterized in that, It is divided into two stages: Stage 1: React the following compounds together: Equation (4) Formula (5), Compound A To form the structure of the following formula (6): Equation (6); In formula (5), L is selected from: hydrogen, C1~C6 alkyl, C2~C6 olefin, CF3, phenyl, halogen, phenoxy, C3-C7 cycloalkyl, amino; Compound A is selected from: , ; In formula (6), the Z1 group is selected from: hydrogen, C1~C6 alkyl, C1~C6 alkoxy, CF3, phenyl, halogen, phenoxy, C3-C7 cycloalkyl, or , ; In formula (6), the Z2 group is selected from: , ; In formulas (4) and (6), R is selected from: hydrogen, hydroxyl, allyl, C1-C6 alkyl, C1-C6 alkoxy, CF3, OCF3, phenyl, halogen, phenoxy, C3-C7 cycloalkyl; n represents the number of R substituents, which can be 1 to 3; Phase 2: The compound of formula (6) is reacted with an aldehyde-containing compound selected from formaldehyde, formaldehyde aqueous solution, trioxymethylene, and paraoxymethylene to form a compound with the structure shown in formula (1).

4. The preparation method according to claim 3, characterized in that, The structure of equation (5) is selected from one of the following: 。 5. The preparation method according to claim 3, characterized in that, In stage 1, the reaction conditions are as follows: the ratio of compound (4), (5) and structural formula A is between 1:1.2:1 and 1:2:1; the reaction solvent is selected from one or more of the following: methanol, ethanol, dichloromethane, chloroform, toluene, xylene, tetrahydrofuran, diethyl ether, methyl tert-butyl ether, methyl isobutyl ketone, acetonitrile, nitrobenzene, chlorobenzene, o-dichlorobenzene, N,N-dimethylformamide, N,N-diethylacetamide, dioxane, sulfolane, dimethylacetamide, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, 1,3-dimethylpropylene urea, N-methylpyrrolidone, N,N'-dimethylethylidene urea, dimethyl sulfoxide; the reaction temperature is 0 ℃ to 120 ℃; the reaction time is 30 minutes to 48 hours; after the reaction, the product is precipitated by adding it dropwise to methanol or acetone and water as a precipitant, and then washed with deionized water to obtain the product of stage 1.

6. The preparation method according to claim 3, characterized in that, In stage 2, the reaction conditions are as follows: the product of stage 1 is mixed with aldehydes in a ratio of 1:1 to 1:10; the reaction solvent is selected from one or more of the following: chloroform, toluene, xylene, tetrahydrofuran, diethyl ether, methyl tert-butyl ether, methyl isobutyl ketone, acetonitrile, nitrobenzene, chlorobenzene, N,N-dimethylformamide, N,N-diethylacetamide, dioxane, sulfolane, dimethylacetamide, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, 1,3-dimethylpropylene urea, N-methylpyrrolidone, N,N'-dimethylethylidene urea, dimethyl sulfoxide; the reaction temperature is 0 ℃ to 120 ℃, and the reaction time is 30 minutes to 48 hours; after the reaction, the product is precipitated dropwise in methanol or acetone and water, and washed with deionized water to obtain the product, namely, a phosphorus-based benzoxazine containing a triazine structure.

7. A thermosetting epoxy resin composition, characterized in that, It contains at least one phosphorus-based benzoxazine compound with a triazine structure as described in claim 1; specifically, it includes epoxy resin, phosphorus-based benzoxazine compound with a triazine structure, co-curing agent, and curing accelerator; based on a total mass of 100 parts, epoxy resin accounts for 15-60 parts, phosphorus-containing active ester flame retardant accounts for 5-60 parts, co-curing agent accounts for 0-60 parts, and curing accelerator accounts for 0.3-5 parts.

8. The thermosetting epoxy resin composition according to claim 7, characterized in that: The epoxy resin is selected from bisphenol A type epoxy resin, bisphenol B type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenolic epoxy resin, hydrogenated bisphenol A type epoxy resin, tetrabromobisphenol A type epoxy resin, dicyclopentadiene phenol epoxy resin, biphenyl type epoxy resin, binatidine type epoxy resin, naphthol type epoxy resin, and diaminodiphenylmethane tetraglycidyl epoxy resin; The co-curing agent is selected from phenolic resin, phenolic resin reactive ester, dicyclopentadiene reactive ester, polyester resin, amino resin, benzoxazine resin, liquid polyurethane, polysulfide rubber, dicyclopentadiene phenolic resin, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl sulfone, dicyandiamide, m-phenylenediamine, p-phenylenediamine, adipate dihydrazide, phthalic anhydride, tetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methyl nadiazid, pyromellitic anhydride, and benzophenone tetracarboxylic anhydride. The curing accelerator is selected from: triphenylphosphine, 4-dimethylaminopyridine, 2,4,5-triphenylimidazolium, tetraphenylphosphonium bromide, N-methylimidazolium, imidazolium, benzyltriphenylphosphonium bromide, ethyltriphenylphosphonium acetate, 1-cyanoethyl-2-methylimidazolium, 2-methylimidazolium, 2-ethyl-4-methylimidazolium, 1-cyanoethyl-2-ethyl-4-methylimidazolium, 2,4,6-tris(dimethylaminomethyl)phenol; Thermosetting resin compositions may also include fillers, release agents, leveling agents, reactive diluents, and solvents.

9. The use of the thermosetting epoxy resin composition as described in claim 7 or 8 in the preparation of electronic packaging materials.

10. The application according to claim 9, wherein the composition is compounded with one or more of polytetrafluoroethylene microspheres, nano-silica, micron-sized silica, boron nitride, magnesium oxide, chopped glass fiber, glass fiber cloth, and high-performance polymer fiber and then cured to form a resin for manufacturing molding compounds, substrates, carriers, printed circuit boards, and laminates in the field of electronic packaging.

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