Inherently flame retardant / antibacterial organophosphorus modified unsaturated resins and methods for their preparation

Abstract

The application relates to an intrinsic flame-retardant / antibacterial organic phosphine modified unsaturated resin and a preparation method thereof. The organic phosphine modified unsaturated resin is a cured product with a crosslinked structure formed by ring-opening polymerization of a phosphorus-containing unsaturated resin and a multifunctional epoxy resin, and has good flame-retardant and antibacterial properties.

Description

Technical Field

[0001] This application relates to the field of flame-retardant / antibacterial materials, and more particularly to an intrinsically flame-retardant / antibacterial organophosphorus modified unsaturated resin and its preparation method. Background Technology

[0002] The microbial system is complex, and some harmful microorganisms pose a significant threat to human health, causing countless deaths each year in people and animals due to infectious diseases caused by bacteria, viruses, and fungi. Phosphorus and nitrogen belong to the same group and share some similar properties. Compared to nitrogen atoms, phosphorus has a larger atomic radius and lower electronegativity. Therefore, quaternary phosphonium salts exhibit weak association, which facilitates the attachment of quaternary phosphonium salt groups to the phospholipid bilayer of microorganisms via electrostatic interactions, disrupting their structure, causing leakage of cell contents, and thus inhibiting microbial growth and reproduction. Furthermore, antimicrobial materials containing quaternary phosphonium salt structures possess broad-spectrum and highly efficient antimicrobial properties, generally exhibiting superior antimicrobial performance and showing considerable development potential in the field of cationic antimicrobial agents.

[0003] The biggest drawback of epoxy resin is its flammability. To improve the flame retardancy of epoxy resin, halogenated flame-retardant epoxy resins are currently the most widely used in industry. However, the use of halogenated flame retardants has revealed serious problems: it significantly reduces the UV resistance of the flame-retardant substrate and produces more smoke, corrosive gases, and toxic gases during combustion. Due to environmental concerns, the use of halogenated flame retardants has been restricted to varying degrees, making halogen-free epoxy resins the main trend in epoxy resin development and application. Summary of the Invention

[0004] This application provides an organophosphorus-modified unsaturated resin, which has good flame retardant and antibacterial properties.

[0005] The organophosphorus modified unsaturated resin provided in this application is a cured product with a cross-linked structure formed by ring-opening polymerization of phosphorus-containing unsaturated resin and multifunctional epoxy resin.

[0006] In one embodiment, the multifunctional epoxy resin is any one or more of the following: bisphenol A type epoxy resin, phenolic epoxy resin, bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, diglycidyl ether, 1,6-hexanediol diglycidyl ether, ethylene glycol diglycidyl ether, glycerol triglycidyl ether, triglycidyl-p-aminophenol, trimethylolpropane triglycidyl ether, trimethylolethane triglycidyl ether, triglycidyl-m-aminophenol, and triglycidyl-m-cresol.

[0007] In one embodiment, the molar ratio of the phosphine group of the phosphorus-containing unsaturated resin to the epoxy group of the multifunctional epoxy resin is 1:(1-1.2).

[0008] In one embodiment, the phosphorus-containing unsaturated resin is obtained by reacting an unsaturated resin with an organophosphorus compound, wherein the molar ratio of the unsaturated resin to the organophosphorus compound is 1:(2-5).

[0009] Another aspect of this application provides a method for preparing organophosphorus-modified unsaturated resins, comprising:

[0010] Under an inert atmosphere, the unsaturated resin in the first solvent is reacted with an organophosphorus compound at 40-80°C, causing the reaction product to precipitate and yielding a phosphorus-containing unsaturated resin.

[0011] The phosphorus-containing unsaturated resin is mixed with a multifunctional epoxy resin and then cured to obtain an organophosphorus-modified unsaturated resin.

[0012] In one embodiment, the molar ratio of the unsaturated resin to the organophosphorus compound is 1:(2-5).

[0013] In one embodiment, the molar ratio of the phosphine group of the phosphorus-containing unsaturated resin to the epoxy group of the multifunctional epoxy resin is 1:(1-1.2).

[0014] In one embodiment, the multifunctional epoxy resin is any one or more of the following: bisphenol A type epoxy resin, phenolic epoxy resin, bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, diglycidyl ether, 1,6-hexanediol diglycidyl ether, ethylene glycol diglycidyl ether, glycerol triglycidyl ether, triglycidyl-p-aminophenol, trimethylolpropane triglycidyl ether, trimethylolethane triglycidyl ether, triglycidyl-m-aminophenol, and triglycidyl-m-cresol.

[0015] In one embodiment, the first solvent is any one or more of chloroform, dichloromethane, tetrahydrofuran, N,N-dimethylformamide, N,N-dimethylacetamide, and dimethyl sulfoxide.

[0016] In one embodiment, the curing is performed by holding at 40-80°C for 1-24 hours, then at 60-100°C for 1-12 hours, and finally at 80-120°C for 1-6 hours.

[0017] The organophosphorus-modified unsaturated resin provided in this application has good flame retardant and antibacterial properties. Attached Figure Description

[0018] Figure 1 The 1H NMR spectrum of the unsaturated resin prepared in Example 1 is shown.

[0019] Figure 2The 1H NMR spectrum of the phosphorus-containing unsaturated resin prepared in Example 1 is shown.

[0020] Figure 3(a) shows a physical image of the intrinsic flame-retardant / antibacterial organophosphorus modified unsaturated resin prepared in Example 1; Figure 3(b) shows a physical image of the intrinsic flame-retardant / antibacterial organophosphorus modified unsaturated resin prepared in Example 2.

[0021] Figure 4(a) shows the antibacterial activity of the intrinsically flame-retardant / antibacterial organophosphorus modified unsaturated resin prepared in Example 1 against Staphylococcus aureus; Figure 4(b) shows the antibacterial activity of the intrinsically flame-retardant / antibacterial organophosphorus modified unsaturated resin prepared in Example 2 against Staphylococcus aureus. Detailed Implementation

[0022] This application provides an organophosphorus-modified unsaturated resin, which has good flame retardant and antibacterial properties.

[0023] The organophosphorus modified unsaturated resin provided in this application is a cured product with a cross-linked structure formed by ring-opening polymerization of phosphorus-containing unsaturated resin and multifunctional epoxy resin.

[0024] Unsaturated resins contain hydroxyl groups and unsaturated double bonds, which can be modified by functional groups to improve their properties. Phosphorus is an element that readily forms compounds; its POC or PC bonds exhibit excellent stability. Phosphorus-based flame retardant systems can increase the char formation rate of materials, especially oxygen-containing polymers, during combustion. The resulting carbon layer is resistant to oxidation, and the phosphoric acid can also prevent ignition by covering the carbon layer. Organophosphorus compounds can undergo addition reactions with vinyl groups and are introduced into the system, improving flame retardant properties. The introduction of quaternary phosphonium salt structures into the system enhances antibacterial properties.

[0025] In one embodiment, the multifunctional epoxy resin is any one or more of the following: bisphenol A type epoxy resin, phenolic epoxy resin, bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, diglycidyl ether, 1,6-hexanediol diglycidyl ether, ethylene glycol diglycidyl ether, glycerol triglycidyl ether, triglycidyl-p-aminophenol, trimethylolpropane triglycidyl ether, trimethylolethane triglycidyl ether, triglycidyl-m-aminophenol, and triglycidyl-m-cresol.

[0026] In one embodiment, the molar ratio of the phosphine group of the phosphorus-containing unsaturated resin to the epoxy group of the multifunctional epoxy resin is 1:(1-1.2).

[0027] In one embodiment, the phosphorus-containing unsaturated resin is obtained by reacting an unsaturated resin with an organophosphorus compound, wherein the molar ratio of the unsaturated resin to the organophosphorus compound is 1:(2-5).

[0028] Another aspect of this application provides a method for preparing organophosphorus-modified unsaturated resins, comprising:

[0029] Under an inert atmosphere, the unsaturated resin in the first solvent is reacted with an organophosphorus compound at 40-80°C, causing the reaction product to precipitate and yielding a phosphorus-containing unsaturated resin.

[0030] The phosphorus-containing unsaturated resin is mixed with a multifunctional epoxy resin and then cured to obtain an organophosphorus-modified unsaturated resin.

[0031] In one embodiment, the molar ratio of the unsaturated resin to the organophosphorus compound is 1:(2-5).

[0032] In one embodiment, the molar ratio of the phosphine group of the phosphorus-containing unsaturated resin to the epoxy group of the multifunctional epoxy resin is 1:(1-1.2).

[0033] In one embodiment, the multifunctional epoxy resin is any one or more of the following: bisphenol A type epoxy resin, phenolic epoxy resin, bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, diglycidyl ether, 1,6-hexanediol diglycidyl ether, ethylene glycol diglycidyl ether, glycerol triglycidyl ether, triglycidyl-p-aminophenol, trimethylolpropane triglycidyl ether, trimethylolethane triglycidyl ether, triglycidyl-m-aminophenol, and triglycidyl-m-cresol.

[0034] In one embodiment, the first solvent is any one or more of chloroform, dichloromethane, tetrahydrofuran, N,N-dimethylformamide, N,N-dimethylacetamide, and dimethyl sulfoxide.

[0035] In one embodiment, the curing is performed by holding at 40-80°C for 1-24 hours, then at 60-100°C for 1-12 hours, and finally at 80-120°C for 1-6 hours.

[0036] In one embodiment, the unsaturated resin is obtained by reacting epoxy resin with acrylic acid at 70-110°C in an inert atmosphere in the presence of a polymerization inhibitor until the acid value is less than 10 mg KOH / g.

[0037] In one embodiment, the molar ratio of the epoxy resin to the acrylic acid is 1:(2-5).

[0038] In one embodiment, the epoxy resin is any one or more of bisphenol A type epoxy resin, phenolic epoxy resin, bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, diglycidyl ether, 1,6-hexanediol diglycidyl ether, and ethylene glycol diglycidyl ether.

[0039] In one embodiment, the polymerization inhibitor is any one or more of hydroquinone, 4-methoxyphenol, 2,5-dimethylhydroquinone, and 2,6-di-tert-butyl-p-cresol.

[0040] In one embodiment, the organophosphorus compound is diphenylphosphorus. Diphenylphosphorus is an organophosphorus reagent that can undergo an addition reaction with vinyl groups and be introduced into the system to improve the flame retardant properties of the material.

[0041] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without inventive effort are within the scope of protection of this invention.

[0042] Unless otherwise specified, the experimental methods described in the following examples are conventional methods; unless otherwise specified, the reagents and materials are commercially available.

[0043] Example 1

[0044] Under a nitrogen atmosphere, epoxy resin E51 (10g) and acrylic acid (3.7g) were reacted in the presence of hydroquinone (0.014g) as a polymerization inhibitor at 70℃. The acid value was monitored during the reaction, and stopped when it fell below 10mg KOH / g. Chloroform was added to completely dissolve the product. The reaction solution was then subjected to alkaline washing and vacuum evaporation to remove the solvent and water, yielding the unsaturated resin product. Figure 1 The 1H NMR spectrum of the unsaturated resin is shown.

[0045] Unsaturated resin (0.54 g) in 10 mL of chloroform was reacted with diphenylphosphine (0.37 g) under a nitrogen atmosphere at 40 °C for 24 h. After the reaction was complete, the mixture was precipitated with anhydrous diethyl ether, and the lower precipitate was collected. The precipitate was then dried under vacuum at 30 °C to obtain a solid form of phosphorus-containing unsaturated resin. Figure 2 The proton NMR spectrum of the phosphorus-containing unsaturated resin is shown.

[0046] Phosphorus-containing unsaturated resin (0.46 g) and glycerol triglycidyl ether (0.17 g) were mixed evenly, transferred to a mold, and vacuum degassed. The mixture was then gradually heated and cured: 40°C for 24 h, 60°C for 12 h, and finally 80°C for 6 h. After cooling to room temperature, an intrinsically flame-retardant / antibacterial organophosphorus modified unsaturated resin was obtained.

[0047] Example 2

[0048] Under a nitrogen atmosphere, epoxy resin E51 (10g) and acrylic acid (9.2g) were reacted in the presence of hydroquinone (0.19g) as a polymerization inhibitor at a temperature of 110℃. During the reaction, the acid value was monitored and stopped when it fell below 10mg KOH / g. Chloroform was added to completely dissolve the product. The reaction solution was then subjected to alkaline washing and vacuum evaporation to remove the solvent and water, yielding the unsaturated resin product.

[0049] Under a nitrogen atmosphere, 0.54 g of unsaturated resin in 10 mL of chloroform was reacted with 0.93 g of diphenylphosphine at 80 °C for 1 h. After the reaction was complete, the resin was precipitated with anhydrous diethyl ether, and the lower precipitate was collected. The precipitate was then dried under vacuum at 30 °C to obtain a solid form of phosphorus-containing unsaturated resin.

[0050] Phosphorus-containing unsaturated resin (0.46 g) and triglycidyl-p-aminophenol (0.18 g) were mixed evenly, transferred to a mold, and vacuum degassed. The mixture was then gradually heated and cured: 80°C for 1 hour, then 100°C for 1 hour, and finally 120°C for 1 hour. After cooling to room temperature, an intrinsically flame-retardant / antibacterial organophosphorus-modified unsaturated resin was obtained.

[0051] Example 3

[0052] Under a nitrogen atmosphere, epoxy resin E51 (10 g) and acrylic acid (4.4 g) were reacted in the presence of polymerization inhibitor 4-methoxyphenol (0.072 g) at a reaction temperature of 110 °C. During the reaction, the acid value was monitored and stopped when it fell below 10 mg KOH / g. Chloroform was added to completely dissolve the product. The reaction solution was then subjected to alkali washing and vacuum evaporation to remove the solvent and water, yielding the unsaturated resin product.

[0053] Under a nitrogen atmosphere, 0.54 g of unsaturated resin in 10 mL of chloroform was reacted with 0.47 g of diphenylphosphine at 40 °C for 24 h. After the reaction was complete, the resin was precipitated with anhydrous diethyl ether, and the lower precipitate was collected. The precipitate was then dried under vacuum at 30 °C to obtain a solid form of phosphorus-containing unsaturated resin.

[0054] Phosphorus-containing unsaturated resin (0.46 g) and glycerol triglycidyl ether (0.17 g) were mixed evenly and transferred to a mold. After vacuum degassing, the mixture was gradually heated and cured. The curing process consisted of maintaining the temperature at 40°C for 24 hours, then at 60°C for 12 hours, and finally at 80°C for 6 hours. After cooling to room temperature, an intrinsically flame-retardant / antibacterial organophosphorus modified unsaturated resin was obtained.

[0055] Example 4

[0056] Under a nitrogen atmosphere, epoxy resin E51 (10g) and acrylic acid (4.4g) were reacted in the presence of hydroquinone (0.072g) as a polymerization inhibitor at a temperature of 70℃. During the reaction, the acid value was monitored and stopped when it fell below 10mg KOH / g. Dichloromethane was added to completely dissolve the product. The reaction solution was then subjected to alkaline washing and vacuum evaporation to remove the solvent and water, yielding the unsaturated resin product.

[0057] Under a nitrogen atmosphere, 0.54 g of unsaturated resin in 10 mL of chloroform was reacted with 0.47 g of diphenylphosphine at 40 °C for 24 h. After the reaction was complete, the resin was precipitated with anhydrous diethyl ether, and the lower precipitate was collected. The precipitate was then dried under vacuum at 30 °C to obtain a solid form of phosphorus-containing unsaturated resin.

[0058] Phosphorus-containing unsaturated resin (0.46 g) and glycerol triglycidyl ether (0.17 g) were mixed evenly and transferred to a mold. After vacuum degassing, the mixture was gradually heated and cured. The curing process consisted of maintaining the temperature at 40°C for 24 hours, then at 60°C for 12 hours, and finally at 80°C for 6 hours. After cooling to room temperature, an intrinsically flame-retardant / antibacterial organophosphorus modified unsaturated resin was obtained.

[0059] Example 5

[0060] Under a nitrogen atmosphere, epoxy resin E51 (10g) and acrylic acid (4.4g) were reacted in the presence of hydroquinone (0.072g) as a polymerization inhibitor at a temperature of 70℃. During the reaction, the acid value was monitored and stopped when it fell below 10mg KOH / g. Toluene was added and heated to completely dissolve the product. The reaction solution was then subjected to alkaline washing and vacuum evaporation to remove the solvent and water, yielding the unsaturated resin product.

[0061] Under a nitrogen atmosphere, 0.54 g of unsaturated resin in 10 mL of chloroform was reacted with 0.47 g of diphenylphosphine at 40 °C for 24 h. After the reaction was complete, the resin was precipitated with anhydrous diethyl ether, and the lower precipitate was collected. The precipitate was then dried under vacuum at 30 °C to obtain a solid form of phosphorus-containing unsaturated resin.

[0062] Phosphorus-containing unsaturated resin (0.46 g) and glycerol triglycidyl ether (0.17 g) were mixed evenly and transferred to a mold. After vacuum degassing, the mixture was gradually heated and cured. The curing process consisted of maintaining the temperature at 40°C for 24 hours, then at 60°C for 12 hours, and finally at 80°C for 6 hours. After cooling to room temperature, an intrinsically flame-retardant / antibacterial organophosphorus modified unsaturated resin was obtained.

[0063] Example 6

[0064] Under a nitrogen atmosphere, epoxy resin E51 (10g) and acrylic acid (4.4g) were reacted in the presence of hydroquinone (0.072g) as a polymerization inhibitor at a temperature of 70℃. During the reaction, the acid value was monitored and stopped when it fell below 10mg KOH / g. Chloroform was added to completely dissolve the product. The reaction solution was then subjected to alkaline washing and vacuum evaporation to remove the solvent and water, yielding the unsaturated resin product.

[0065] Under a nitrogen atmosphere, 0.54 g of unsaturated resin in 10 mL of tetrahydrofuran was reacted with 0.47 g of diphenylphosphine at 40 °C for 24 h. After the reaction was complete, the resin was precipitated with anhydrous diethyl ether, the lower precipitate was collected, and then the precipitate was dried under vacuum at 50 °C to obtain a solid form of phosphorus-containing unsaturated resin.

[0066] Phosphorus-containing unsaturated resin (0.46 g) and glycerol triglycidyl ether (0.17 g) were mixed evenly and transferred to a mold. After vacuum degassing, the mixture was gradually heated and cured. The curing process consisted of maintaining the temperature at 40°C for 24 hours, then at 60°C for 12 hours, and finally at 80°C for 6 hours. After cooling to room temperature, an intrinsically flame-retardant / antibacterial organophosphorus modified unsaturated resin was obtained.

[0067] Example 7

[0068] Bisphenol A diglycidyl ether (10 g) and acrylic acid (4.4 g) were reacted under a nitrogen atmosphere in the presence of hydroquinone (0.072 g) as a polymerization inhibitor at a temperature of 110 °C. The acid value was monitored during the reaction, and the reaction was stopped when the acid value was less than 10 mg KOH / g. Chloroform was added to completely dissolve the product. The reaction solution was then subjected to alkaline washing and vacuum evaporation to remove the solvent and water, yielding the unsaturated resin product.

[0069] Under a nitrogen atmosphere, 0.48 g of unsaturated resin in 10 mL of chloroform was reacted with 0.47 g of diphenylphosphine at 40 °C for 24 h. After the reaction was complete, the resin was precipitated with anhydrous diethyl ether, and the lower precipitate was collected. The precipitate was then dried under vacuum at 30 °C to obtain a solid form of phosphorus-containing unsaturated resin.

[0070] Phosphorus-containing unsaturated resin (0.43g) and glycerol triglycidyl ether (0.17g) were mixed evenly and transferred to a mold. After vacuum degassing, the mixture was gradually heated and cured. The curing process was carried out at 40℃ for 24 hours, then at 60℃ for 12 hours, and finally at 80℃ for 6 hours. After cooling to room temperature, an intrinsically flame-retardant / antibacterial organophosphorus modified unsaturated resin was obtained.

[0071] Example 8

[0072] Bisphenol F diglycidyl ether (8.0 g) and acrylic acid (4.4 g) were reacted under a nitrogen atmosphere in the presence of hydroquinone (0.062 g) as a polymerization inhibitor at a temperature of 110 °C. The acid value was monitored during the reaction, and the reaction was stopped when the acid value was less than 10 mg KOH / g. Chloroform was added to completely dissolve the product. The reaction solution was then subjected to alkaline washing and vacuum evaporation to remove the solvent and water, yielding the unsaturated resin product.

[0073] Under a nitrogen atmosphere, 0.46 g of unsaturated resin in 10 mL of chloroform was reacted with 0.47 g of diphenylphosphine at 40 °C for 24 h. After the reaction was complete, the resin was precipitated with anhydrous diethyl ether, and the lower precipitate was collected. The precipitate was then dried under vacuum at 30 °C to obtain a solid form of phosphorus-containing unsaturated resin.

[0074] Phosphorus-containing unsaturated resin (0.41g) and glycerol triglycidyl ether (0.17g) were mixed evenly and transferred to a mold. After vacuum degassing, the mixture was gradually heated and cured. The curing process was carried out at 40℃ for 24 hours, then at 60℃ for 12 hours, and finally at 80℃ for 6 hours. After cooling to room temperature, an intrinsically flame-retardant / antibacterial organophosphorus modified unsaturated resin was obtained.

[0075] Flame retardant performance test

[0076] To verify the flame retardant properties, the intrinsically flame-retardant / antibacterial organophosphorus modified unsaturated resins prepared in Examples 1-8 were subjected to UL-94 testing.

[0077] Table 1

[0078]

[0079] Note: V-0 level is defined as follows: when the material is exposed to a flame twice for 10 seconds each time, and the total burning time does not exceed 50 seconds, and no burning material drips or the dripping material cannot ignite the absorbent cotton during the test.

[0080] As can be seen from the test results in Table 1, the intrinsically flame-retardant / antibacterial organophosphorus modified unsaturated resins prepared in Examples 1-8 all have a UL-94 rating of V-0.

[0081] Antibacterial performance test

[0082] Antibacterial activity was assessed using a live-dead bacteria fluorescence staining method, with *Staphylococcus aureus* selected as the test species. Bacterial suspensions were spread on agar plates and incubated overnight at 37°C. A single colony was then inoculated into 40 ml of LB broth and incubated at 37°C for 8–12 h at 200 rpm. The LB broth was then diluted to a suitable bacterial concentration (OD = ~0.1 at 600 nm UV). The solidified samples were first immersed in PBS buffer and then sterilized by UV irradiation for a period of time. The solidified samples were then placed in 12-well plates containing 3 ml of bacterial suspension and incubated at 37°C for 12 h. Finally, all samples were rinsed with PBS buffer to remove any unadhered bacteria. Bacteria adhering to the sample surface were stained using a diluted Live / Dead Back Light kit (Thermo Fisher Scientific Inc., NY), and the staining was observed using an inverted fluorescence microscope.

[0083] The number of viable bacteria is denoted as N. L The number of dead bacteria is denoted as N. D Antibacterial ability R A Expressed according to the following formula.

[0084]

[0085] Figures 4(a) and 4(b) show the antibacterial activity of the intrinsically flame-retardant / antibacterial organophosphorus modified unsaturated resins prepared in Examples 1 and 2 against Staphylococcus aureus, respectively. The bright spots in the figures represent the number of viable bacteria, and the tests show that the antibacterial rates are 92.0% and 93.3%, respectively.

[0086] The intrinsically flame-retardant / antibacterial organophosphorus modified unsaturated resins prepared in Examples 1-8 all exhibit significant antibacterial capabilities.

[0087] It should be noted that the technical solutions or features described in the above embodiments can be combined or supplemented with each other without conflict. The scope of protection of this application is not limited to the precise structures described in the above embodiments and shown in the accompanying drawings; all modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. An organophosphorus-modified unsaturated resin, characterized in that, The organophosphorus modified unsaturated resin is a cured product with a cross-linked structure formed by ring-opening polymerization of phosphorus-containing unsaturated resin and multifunctional epoxy resin. The phosphorus-containing unsaturated resin is obtained by reacting an unsaturated resin with an organophosphorus compound, wherein the molar ratio of the unsaturated resin to the organophosphorus compound is 1:(2-5). The unsaturated resin is obtained by reacting epoxy resin and acrylic acid at 70-110°C in an inert atmosphere in the presence of a polymerization inhibitor until the acid value is less than 10 mg KOH / g. The organophosphine compound is diphenylphosphine; The molar ratio of the phosphine group in the phosphorus-containing unsaturated resin to the epoxy group in the multifunctional epoxy resin is 1:(1-1.2).

2. The organophosphorus-modified unsaturated resin according to claim 1, characterized in that, The multifunctional epoxy resin is any one or more of the following: phenolic epoxy resin, bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, diglycidyl ether, 1,6-hexanediol diglycidyl ether, ethylene glycol diglycidyl ether, glycerol triglycidyl ether, triglycidyl-p-aminophenol, trimethylolpropane triglycidyl ether, trimethylolethane triglycidyl ether, triglycidyl-m-aminophenol, and triglycidyl-m-cresol.

3. A method for preparing organophosphorus-modified unsaturated resin, comprising: Under an inert atmosphere, the unsaturated resin in the first solvent is reacted with an organophosphorus compound at 40-80°C, causing the reaction product to precipitate and yielding a phosphorus-containing unsaturated resin. The phosphorus-containing unsaturated resin is mixed with a multifunctional epoxy resin and then cured to obtain an organophosphorus-modified unsaturated resin. The phosphorus-containing unsaturated resin is obtained by reacting an unsaturated resin with an organophosphorus compound, wherein the molar ratio of the unsaturated resin to the organophosphorus compound is 1:(2-5). The unsaturated resin is obtained by reacting epoxy resin and acrylic acid at 70-110°C in an inert atmosphere in the presence of a polymerization inhibitor until the acid value is less than 10 mg KOH / g. The organophosphine compound is diphenylphosphine; The molar ratio of the phosphine group in the phosphorus-containing unsaturated resin to the epoxy group in the multifunctional epoxy resin is 1:(1-1.2).

4. The method according to claim 3, characterized in that, The multifunctional epoxy resin is any one or more of the following: phenolic epoxy resin, bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, diglycidyl ether, 1,6-hexanediol diglycidyl ether, ethylene glycol diglycidyl ether, glycerol triglycidyl ether, triglycidyl-p-aminophenol, trimethylolpropane triglycidyl ether, trimethylolethane triglycidyl ether, triglycidyl-m-aminophenol, and triglycidyl-m-cresol.

5. The method according to claim 3, characterized in that, The first solvent is any one or more of chloroform, dichloromethane, tetrahydrofuran, N,N-dimethylformamide, N,N-dimethylacetamide, and dimethyl sulfoxide.

6. The method according to claim 3, characterized in that, The curing process involves maintaining the temperature at 40-80°C for 1-24 hours, then at 60-100°C for 1-12 hours, and finally at 80-120°C for 1-6 hours.

Images