Epoxy resin containing high-durability hyperbranched flame-retardant smoke suppressant and preparation method thereof

Abstract

The invention discloses epoxy resin containing a high-durability hyperbranched flame-retardant smoke suppressant and a preparation method of the epoxy resin, and relates to the technical field of epoxy resin. According to the invention, DMMP is hyperbranched, and small molecules are converted into hyperbranched macromolecules, so that the prepared flame-retardant smoke suppressant is not easy to migrate to the surface of a material, the durability of the flame-retardant smoke suppressant is realized, and finally, the comprehensive properties of epoxy resin in the aspects of long-acting flame retardance, smoke suppression, physical properties and the like are improved.

Description

Technical Field

[0001] This invention relates to the field of epoxy resin technology, specifically to an epoxy resin containing a highly durable hyperbranched flame retardant and smoke suppressant, and its preparation method. Background Technology

[0002] Polymer materials are widely used in construction and home furnishing. Among them, epoxy resin (EP) is widely used as both a bulk and coating material due to its unique physical bonds and properties. However, its molecular structure contains a large number of flammable elements such as C, H, O, and N, as well as benzene ring structures, resulting in a limiting oxygen index (LOI) of 17-19%. When burned, it produces a large amount of heat radiation accompanied by black and white smoke, seriously threatening people's lives and property. The smoke contains large amounts of toxic gases such as CO and HCN, which can easily cause poisoning and asphyxiation. The high-temperature smoke contains a large amount of heat, which can cause thermal damage and accelerate heat dissipation. In addition, white smoke reflects light, and black smoke reduces visibility, severely affecting fire rescue and evacuation operations. It is worth noting that this problem is particularly serious in confined spaces, causing irreversible harm to people's lives and the social environment.

[0003] Adding flame retardants to epoxy resins is one of the most effective ways to obtain fire-safe epoxy resins. With increasing global environmental awareness, halogenated flame retardants are gradually being replaced due to their environmental and biological toxicity. Flame retardants are developing towards high efficiency, halogen-free, non-toxic, and environmentally friendly directions. Halogen-free flame retardants are commonly classified into inorganic metal hydroxides, phosphorus-based, nitrogen-based, and phosphorus-nitrogen-based flame retardants. Among them, phosphorus-based flame retardants have become an important development direction for environmentally friendly flame retardant technology due to their high efficiency and other advantages. Among phosphorus-based flame retardants, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) has been widely studied and applied to the flame-retardant modification of epoxy resins. Despite its excellent flame retardant properties, DOPO has significant drawbacks: First, DOPO has high migration, causing the flame retardant and mechanical properties of epoxy resin to degrade significantly over time; second, the release of DOPO poses environmental and health risks, as it can be absorbed by human skin or seep into rivers and lakes, causing water pollution; furthermore, the benzene ring structure of DOPO easily leads to increased smoke release during combustion.

[0004] In contrast, dimethyl methylphosphonate (DMMP), as a low-molecular-weight phosphorus-based flame retardant, has advantages such as high phosphorus content, excellent flame retardant efficiency, and no aromatic ring structure. However, DMMP has a small molecular weight and high volatility, making it difficult to maintain long-term stability in epoxy systems, which limits its direct application.

[0005] Therefore, designing durable flame retardant and smoke suppressant suitable for epoxy resins is of great significance for promoting technological progress in the field of flame retardant materials. Summary of the Invention

[0006] The technical problem to be solved by this invention is to overcome the shortcomings of the prior art and provide an epoxy resin containing a high-durability hyperbranched flame retardant and smoke suppressant and its preparation method. In this invention, by hyperbranching DMMP, small molecules are transformed into hyperbranched macromolecules. Through molecular structure design, its compatibility and durability in epoxy resin can be significantly improved, making the prepared flame retardant and smoke suppressant less likely to migrate to the material surface while maintaining a high flame retardant effect. This achieves the durability of the flame retardant and smoke suppressant and ultimately improves the comprehensive performance of epoxy resin in terms of long-lasting flame retardancy, smoke suppression, and physical properties.

[0007] The technical solution of this invention is as follows: On one hand, this invention provides a method for preparing an epoxy resin containing a highly durable hyperbranched flame retardant and smoke suppressant. The epoxy resin containing the highly durable hyperbranched flame retardant and smoke suppressant is obtained by mixing and curing epoxy resin, a flame retardant and smoke suppressant, and a curing agent. The flame retardant and smoke suppressant has the following structural formula: .

[0008] Preferably, the preparation method of the flame retardant and smoke suppressant includes the following steps: S1. Mix hydroxyethyl hexahydrotriazine with dimethyl methylphosphonate until homogeneous to obtain a mixture; S2. Heat the mixture to 120-180℃, add the catalyst, and react for 4-6 hours. S3. Distill the viscous liquid after the reaction under reduced pressure to obtain the flame retardant and smoke suppressant.

[0009] Preferably, in step S1, the molar ratio of hydroxyethyl hexahydrotriazine to dimethyl methylphosphonate is 1:(1-3).

[0010] Preferably, in step S2, the catalyst is an alkaline catalyst, a Lewis acid catalyst, a phase transfer / organic amine catalyst, or an enzyme catalyst, and the amount added is 1-3% of the total mass of hydroxyethyl hexahydrotriazine and dimethyl methylphosphonate.

[0011] Preferably, in step S2, the catalyst is a Lewis acid catalyst (such as ZnCl2, Sc(OTf)3 or tetrabutyl titanate), an alkali metal base catalyst (such as NaOH or KOH), a carbonate (such as K2CO3, Cs2CO3), an organic amine catalyst (such as DBU or triethylamine), a solid base catalyst (such as MgO or hydrotalcite), or a phase transfer catalyst (such as tetrabutylammonium bromide).

[0012] Preferably, in step S2, a heat-collecting magnetic stirrer is used for stirring during the reaction; the reactor is equipped with a condenser and a Dean-Stark separator. During the reaction, the heat-collecting magnetic stirrer provides a uniform and stable heating and stirring environment, improving the heat transfer efficiency of the reaction; the condenser can reflux volatile components in the reaction to prevent loss; the Dean-Stark separator is used to effectively separate the byproduct methanol, thereby promoting the equilibrium of the condensation reaction.

[0013] Preferably, in step S3, the vacuum distillation temperature is 100-180℃ and the time is 2-6h.

[0014] Preferably, when preparing epoxy resin containing a high-durability hyperbranched flame retardant and smoke suppressant, the epoxy resin, flame retardant and smoke suppressant and curing agent are mixed and stirred to obtain a solution. The solution is poured into a mold and vacuum-evacuated at room temperature until there are no air bubbles in the solution in the mold. Then, it is cured at 80-140℃ for 1-4 hours to obtain epoxy resin containing a high-durability hyperbranched flame retardant and smoke suppressant.

[0015] Preferably, the mass ratio of curing agent to epoxy resin is 1:(3-5), and the flame retardant and smoke suppressant accounts for 0.5-1.5 wt.% of the total reaction system.

[0016] Preferably, the curing agent is an amine curing agent (including aliphatic amines, aromatic amines, cyclic aliphatic amines, polyamides, etc.), an acid anhydride curing agent, a phenolic curing agent, a sulfur curing agent, or a latent curing agent.

[0017] Preferably, the curing agent is an aromatic amine curing agent, such as 4,4′-diaminodiphenylmethane (DDM), 4,4′-diaminodiphenyl ether or diaminodiphenyl sulfone, or an aliphatic amine curing agent, such as isophorone diamine or triethylenetetramine.

[0018] On the other hand, the present invention provides an epoxy resin containing a highly durable hyperbranched flame retardant and smoke suppressant, which is prepared by the above-described method for preparing an epoxy resin containing a highly durable hyperbranched flame retardant and smoke suppressant.

[0019] Compared with the prior art, the present invention has the following advantages: 1. This invention uses hydroxyethyl hexahydrotriazine and DMMP for synthesis. By hyperbranching DMMP, small molecules are transformed into hyperbranched macromolecules, making it difficult for the prepared flame retardant and smoke suppressant to migrate to the material surface, thereby achieving the durability of the flame retardant and smoke suppressant and ultimately improving the comprehensive performance of epoxy resin in terms of long-lasting flame retardancy, smoke suppression and physical properties.

[0020] 2. The flame retardant and smoke suppressant prepared by this invention is a novel type of flame retardant and smoke suppressant with a highly branched structure. Compared with traditional linear flame retardant and smoke suppressants, the flame retardant and smoke suppressant of this invention has better compatibility and interfacial bonding ability with materials, and can significantly improve the flame retardant and smoke suppressant performance of materials at a lower addition amount while ensuring the durability of flame retardant epoxy resin.

[0021] 3. The six-membered ring containing nitrogen in the flame retardant and smoke suppressant prepared in this invention forms a triazine ring during heating, reducing the formation of smoke precursors, promoting sedimentation, and increasing the char layer, thereby achieving a good smoke suppression and flame retardant effect. DMMP and epoxy resin contain a large number of O, N, and H atoms, which are linked together by hydrogen bonds. The flame retardant and smoke suppressant prepared in this invention enhances this hydrogen bond connection, reduces its migration effect, and ensures its durability.

[0022] 4. Compared with existing flame retardants and smoke suppressants applicable to epoxy resins, the flame retardant and smoke suppressant prepared in this invention is not only applicable to epoxy resins, but also of great significance for promoting technological progress in the field of flame retardant materials. Attached Figure Description

[0023] Figure 1 This is the FTIR spectrum of the flame retardant and smoke suppressant DHTST-1 prepared in Example 1 of this invention.

[0024] Figure 2 It is the flame retardant and smoke suppressant DHTST-1 prepared in Example 1 of this invention. 1 H NMR spectrum.

[0025] Figure 3 This is the FTIR spectrum of the flame retardant and smoke suppressant DHTST-2 prepared in Example 2 of this invention.

[0026] Figure 4 This is the FTIR spectrum of the flame retardant and smoke suppressant DHTST-3 prepared in Example 3 of this invention.

[0027] Figure 5 This is a comparison chart of the total heat release of epoxy resins prepared in Examples 4-6 and Comparative Examples 2-3 of the present invention and pure epoxy resins.

[0028] Figure 6 This is a comparison chart of the total smoke generation of epoxy resins prepared in Examples 4-6 and Comparative Examples 2-3 of the present invention and pure epoxy resins. Detailed Implementation

[0029] The present invention will be further described below with reference to specific embodiments to aid in understanding its content. Unless otherwise specified, the methods used in this invention are conventional methods; the raw materials and apparatus used, unless otherwise specified, are conventional commercially available products.

[0030] Example 1 The preparation method of the flame retardant and smoke suppressant in this embodiment is as follows: 17.52 g (0.08 mol) of hydroxyethyl hexahydrotriazine and 29.76 g (0.24 mol) of DMMP were mixed evenly to obtain a mixture. The mixture was placed in a reactor equipped with a condenser and a Dean-Stark separator and heated to 150 °C with a heat-collecting magnetic stirrer. At this temperature, 0.28 g (1%) of sodium hydroxide was added and the reaction was carried out for 5 h.

[0031] After the reaction was completed, the reaction solution was distilled under reduced pressure at 120℃ for 4 hours to obtain a flame retardant and smoke suppressant, denoted as DHTST-1.

[0032] Example 2 The preparation method of the flame retardant and smoke suppressant in this embodiment is as follows: 17.52 g (0.08 mol) of hydroxyethyl hexahydrotriazine and 19.84 g (0.16 mol) of DMMP were mixed evenly to obtain a mixture. The mixture was placed in a reactor equipped with a condenser and a Dean-Stark separator and heated to 160 °C with a heat-collecting magnetic stirrer. At this temperature, 0.75 g (2%) of sodium hydroxide was added and the reaction was carried out for 4 h.

[0033] After the reaction was completed, the reaction solution was distilled under reduced pressure at 150℃ for 3 hours to obtain a flame retardant and smoke suppressant, denoted as DHTST-2.

[0034] Example 3 The preparation method of the flame retardant and smoke suppressant in this embodiment is as follows: 17.52 g (0.08 mol) of hydroxyethyl hexahydrotriazine was mixed with 9.92 g (0.08 mol) of DMMP. The mixture was placed in a three-necked flask equipped with a condenser and a Dean-Stark separator and heated to 180 °C with a heat-collecting magnetic stirrer. At this temperature, 1.4 g (3%) of sodium hydroxide was added and the reaction was allowed to proceed for 6 h.

[0035] After the reaction was completed, the reaction solution was distilled under reduced pressure at 100℃ for 6 hours to obtain a flame retardant and smoke suppressant, denoted as DHTST-3.

[0036] The infrared spectral analysis results of the flame retardants and smoke suppressants DHTST-1, DHTST-2, and DHTST-3 prepared in Examples 1-3 are as follows: Figure 1-3 As shown: 2856cm -1 1465cm -1 1237cm -1 and 1035cm -1 The absorption peaks attributed to -CH2, -CN, -P=O, and -POC respectively preliminarily confirm the successful synthesis of the target product.

[0037] The flame retardant and smoke suppressant DHTST-1 prepared in Example 1 1 HNMR spectrum as follows Figure 4 As shown, the chemical shift at 1.23 ppm corresponds to the H in P-CH3; the chemical shifts from 3.1 to 3.41 ppm correspond to the H in -CH2 in N-CH2-CH2-OH; the chemical shifts from 3.51 to 3.74 ppm correspond to the H in N-CH2-CH2-OP; the chemical shifts from 3.89 to 4.16 ppm correspond to the methyl H in the O=P-OCH3 part of DMMP; the chemical shift at 0.11 ppm corresponds to the H in the -CH2-CH2- structure; and the chemical shift at 7.24 ppm belongs to the CDCl3 solvent peak.

[0038] In summary, DHTST was prepared by transesterification of hydroxyethyl hexahydrotriazine with DMMP. Infrared and NMR spectra further confirmed that the synthesized product was consistent with the target product.

[0039] Comparative Example 1 The preparation method of the flame retardant and smoke suppressant in this comparative example: 17.52g (0.08mol) of hydroxyethyl hexahydrotriazine and 9.92g (0.08mol) of DMMP were mixed evenly to obtain a mixture. The mixture was heated to 150°C using a common electric heating mantle. At this temperature, 1g of sodium hydroxide was added and the reaction was carried out for 5h.

[0040] Comparative Example 1, which did not use a heat-collecting magnetic stirrer, a reactor with a condenser and a Dean-Stark separator, showed that methanol could not be removed in time during the reaction, the reaction equilibrium was suppressed, the conversion rate of the obtained product was less than 50%, and the amount of by-products increased significantly.

[0041] Comparing Example 1 and Comparative Example 1, it can be seen that the condenser and Dean-Stark separator play an important role in improving yield and selectivity, and the heat-collecting stirrer can effectively improve reaction uniformity and stability.

[0042] Example 4 The preparation method of epoxy resin containing high-durability hyperbranched flame retardant and smoke suppressant in this embodiment is as follows: 5g of curing agent DDM, 20g of epoxy resin E51 and 0.38g of DHTST-1 are mixed and stirred to obtain a solution. The solution is poured into a mold and vacuum-evacuated at room temperature until there are no air bubbles in the solution. Then it is cured at 100°C for 4 hours to obtain epoxy resin containing DHTST-1.

[0043] Example 5 The preparation method of epoxy resin containing high-durability hyperbranched flame retardant and smoke suppressant in this embodiment is as follows: 5g of curing agent DDM, 20g of epoxy resin E51 and 0.25g of DHTST-2 are mixed and stirred to obtain a solution. The solution is poured into a mold and vacuum-evacuated at room temperature until there are no air bubbles in the solution. Then it is cured at 120°C for 2 hours to obtain epoxy resin containing DHTST-2.

[0044] Example 6 The preparation method of epoxy resin containing high-durability hyperbranched flame retardant and smoke suppressant in this embodiment is as follows: 5g of curing agent DDM, 20g of epoxy resin E51 and 0.13g of DHTST-3 are mixed and stirred to obtain a solution. The solution is poured into a mold and vacuum-evacuated at room temperature until there are no air bubbles in the solution in the mold. Then it is cured at 140°C for 1 hour to obtain epoxy resin containing DHTST-3.

[0045] Comparative Example 2 The preparation method of the epoxy resin containing DOPO in this comparative example is as follows: 5g of curing agent DDM, 20g of epoxy resin E51 and 0.38g of DOPO are mixed and stirred to obtain a solution. The solution is poured into a mold and vacuum-evacuated at room temperature until there are no air bubbles in the solution. Then it is cured at 100℃ for 4h to obtain the epoxy resin containing DOPO.

[0046] Comparative Example 3 The preparation method of the DMMP-containing epoxy resin in this comparative example is as follows: 5g of curing agent DDM, 20g of epoxy resin E51 and 0.38g of DMMP are mixed and stirred to obtain a solution. The solution is poured into a mold and vacuum-evacuated at room temperature until there are no air bubbles in the solution in the mold. Then it is cured at 100℃ for 4h to obtain the DMMP-containing epoxy resin.

[0047] The epoxy resins prepared in Examples 4-6 and Comparative Examples 2-3, as well as pure epoxy resin (EP), were subjected to performance tests. The test results are shown in Tables 1-2. Table 1. Performance test results of epoxy resin and pure epoxy resin in Examples 4-6 and Comparative Examples 2-3.

[0048] Table 2. Test results of thermal aging properties of epoxy resin and pure epoxy resin in Examples 4-6 and Comparative Examples 2-3.

[0049] As shown in Tables 1-2, the epoxy resin performance of Comparative Examples 2-3 is significantly inferior to that of Examples 4-6. Comparative Example 2 uses the traditional phosphorus-based flame retardant DOPO, and its performance disadvantage stems from the structural defects of DOPO itself and its insufficient compatibility with the epoxy system. Table 2 shows that Comparative Example 2 initially achieved a UL-94 rating of only V-2 (Examples 4-6 initially reached V-0 / V-1), and failed to pass (NR) after 200 hours of heat aging, while Examples 4-6 maintained a V-0 / V-1 rating after 200 hours of aging. This is because DOPO has a linear small molecule structure, and its compatibility with epoxy resin depends on weak intermolecular forces. Lacking chemical bonds or the spatial constraints of hyperbranched structures, it easily migrates and precipitates to the material surface during long-term use or heat aging, leading to the loss of the effective flame-retardant component. The LOI value decreased from an initial 29.3% to 28.5% after 200 hours of aging, and the flame-retardant efficiency continued to decline. Meanwhile, Table 1 shows that the total smoke production (TSP) of Comparative Example 2 was 21.24 m³. 2 This is significantly higher than that of Example 6 (16.4m). 2 It is only slightly better than pure epoxy resin (23.2m). 2 This is because DOPO molecules contain a benzene ring structure, which easily decomposes during combustion to produce aromatic smoke precursors, making it difficult to form an effective char layer to suppress smoke release. In contrast, DHTST-1 in Example 4 contains a six-membered ring and an nitrogen-containing structure, forming a triazine ring upon heating, which reduces smoke precursor formation and promotes sedimentation, significantly reducing smoke production. Furthermore, in Table 1, the tensile strength, elongation at break, and flexural strength of Comparative Example 2 are all lower than those of Example 4, and even lower than the flexural strength of pure epoxy resin. This is because DOPO has a rigid aromatic structure, which does not match the flexibility of epoxy resin molecular chains, and lacks the "steric hindrance effect" of hyperbranched structures, making it prone to aggregation during dispersion, resulting in weak interfacial bonding and stress concentration under stress, leading to decreased tensile and flexural properties. In contrast, DHTST-1 in Example 4 is a hyperbranched macromolecule; its highly branched structure can form a tighter interfacial interaction with epoxy molecular chains, balancing rigidity and toughness. The THR of Comparative Example 2 is 109.2 MJ / m². 2 The concentration was higher than that in Examples 4-5 (103.8-104.7 MJ / m³). 2 ), compared with Example 6 (109.1 MJ / m 2 While similar to, but without the advantage of durability. This is because the flame retardant mechanism of DOPO relies solely on the condensed phase catalytic char formation of phosphorus, without the synergistic effect of nitrogen; whereas DHTST is a phosphorus-nitrogen synergistic flame retardant, where nitrogen can promote the char formation efficiency of phosphorus, forming a denser char layer to block heat transfer. Therefore, the embodiment has a lower THR and better flame retardant efficiency.

[0050] Comparative Example 3 used unmodified small-molecule DMMP, and its performance disadvantage stemmed from the volatility, migration, and instability of DMMP with the epoxy system. Table 1 shows that Comparative Example 3 had the lowest tensile strength, elongation at break, and flexural strength among all samples, even far lower than pure epoxy resin; its initial THR reached 116.2 MJ / m. 2 It is close to pure epoxy resin (121.6 MJ / m). 2 The flame retardant efficiency is extremely low. This is because DMMP is a small molecule compound with extremely poor compatibility with epoxy resin. It is easily volatilized and lost during epoxy curing and cannot form a stable bond with epoxy molecular chains (lacking the spatial constraint of hyperbranched structure or hydrogen bond reinforcement). This leads to defects inside the material (such as micropores and interface separation), resulting in a significant decrease in mechanical properties. At the same time, its volatility makes it difficult for the flame retardant to function in the condensed phase during combustion, resulting in poor char formation and an inability to suppress heat release. Table 2 shows that after 200 hours of heat aging, the tensile strength of Comparative Example 3 decreased from 36.87 MPa to 34.55 MPa, the elongation at break decreased from 0.88% to 1%, and the flexural strength decreased from 36.35 MPa to 30.1 MPa, all of which are lower than the performance of Examples 4-6 after aging. This is because unmodified DMMP lacks the "anchoring effect" of its hyperbranched structure, leading to further increased volatility during thermal aging. This not only results in the loss of the effective flame-retardant components but may also create voids within the material, causing a continuous decline in mechanical properties. In contrast, the DHTST in this example transforms small-molecule DMMP into large molecules through hyperbranching modification, significantly reducing volatility. Furthermore, DMMP forms hydrogen bonds with O, N, and H atoms in the epoxy system, reducing migration and ensuring stable performance after thermal aging. Although Comparative Example 3 initially achieved a V-0 UL-94 rating, its LOI value was only 29.1%, and both THR and TSP were relatively high. This is because DMMP relies solely on phosphorus for gas-phase flame retardancy (free radical capture), lacking the synergistic charring effect of nitrogen, making it difficult to form a dense char layer to block heat and smoke transfer. In contrast, the DHTST in this example exhibits a phosphorus-nitrogen synergy, with nitrogen promoting phosphorus charring. The char layer further inhibits heat release and smoke generation, achieving a dual effect of "flame retardancy + smoke suppression," thus resulting in superior overall performance.

Claims

1. A method for preparing epoxy resin containing a highly durable hyperbranched flame retardant and smoke suppressant, characterized in that, The epoxy resin containing the highly durable hyperbranched flame retardant and smoke suppressant is prepared by mixing and curing epoxy resin, flame retardant and smoke suppressant, and curing agent, wherein the structural formula of the flame retardant and smoke suppressant is as follows: .

2. The method for preparing epoxy resin containing a highly durable hyperbranched flame retardant and smoke suppressant as described in claim 1, characterized in that, The preparation method of the flame retardant and smoke suppressant includes the following steps: S1. Mix hydroxyethyl hexahydrotriazine with dimethyl methylphosphonate until homogeneous to obtain a mixture; S2. Heat the mixture to 120-180℃, add the catalyst, and react for 4-6 hours. S3. Distill the viscous liquid after the reaction under reduced pressure to obtain the flame retardant and smoke suppressant.

3. The method for preparing epoxy resin containing a highly durable hyperbranched flame retardant and smoke suppressant as described in claim 2, characterized in that, In step S1, the molar ratio of hydroxyethyl hexahydrotriazine to dimethyl methylphosphonate is 1:(1-3).

4. The method for preparing epoxy resin containing a highly durable hyperbranched flame retardant and smoke suppressant as described in claim 2, characterized in that, In step S2, the catalyst is an alkaline catalyst, a Lewis acid catalyst, a phase transfer / organic amine catalyst, or an enzyme catalyst, and the amount added is 1-3% of the total mass of hydroxyethyl hexahydrotriazine and dimethyl methylphosphonate.

5. The method for preparing epoxy resin containing a highly durable hyperbranched flame retardant and smoke suppressant as described in claim 2, characterized in that, In step S2, a heat-collecting magnetic stirrer is used for stirring during the reaction process; the reactor is equipped with a condenser and a Dean-Stark separator.

6. The method for preparing epoxy resin containing a highly durable hyperbranched flame retardant and smoke suppressant as described in claim 2, characterized in that, In step S3, the vacuum distillation temperature is 100-180℃ and the time is 2-6 hours.

7. The method for preparing epoxy resin containing a highly durable hyperbranched flame retardant and smoke suppressant as described in claim 1, characterized in that, To prepare epoxy resin containing a high-durability hyperbranched flame retardant and smoke suppressant, the epoxy resin, flame retardant and smoke suppressant and curing agent are mixed and stirred to obtain a solution. The solution is poured into a mold and vacuum-evacuated at room temperature until there are no air bubbles in the solution. Then it is cured at 80-140℃ for 1-4 hours to obtain epoxy resin containing a high-durability hyperbranched flame retardant and smoke suppressant.

8. The method for preparing epoxy resin containing a highly durable hyperbranched flame retardant and smoke suppressant as described in claim 7, characterized in that, The mass ratio of curing agent to epoxy resin is 1:(3-5), and the flame retardant and smoke suppressant accounts for 0.5-1.5 wt.% of the total reaction system.

9. The method for preparing epoxy resin containing a highly durable hyperbranched flame retardant and smoke suppressant as described in claim 7, characterized in that, The curing agent is an amine curing agent, an acid anhydride curing agent, a phenolic curing agent, a sulfur curing agent, or a latent curing agent.

10. An epoxy resin containing a highly durable hyperbranched flame retardant and smoke suppressant, characterized in that, The epoxy resin containing a highly durable hyperbranched flame retardant and smoke suppressant, as described in claim 1, was prepared.

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