Eugenol / furyl epoxy resin monomer as well as preparation method and application thereof

Abstract

The invention discloses an eugenol / furyl epoxy resin monomer as well as a preparation method and application thereof. The structure of the eugenol / furyl epoxy monomer is as shown in DEF. The eugenol / furyl epoxy resin monomer disclosed by the invention is derived from a bio-based substance, and is wide in source, low in price and relatively low in viscosity at normal temperature. Compared with traditional petroleum-based epoxy resin, the polymer structure has relatively high storage modulus, high carbon residue rate and high overlap shear strength.

Description

Technical Field

[0001] This invention relates to the field of polymer materials, specifically to an eugenol / furan-based epoxy resin monomer, its preparation method, and its application. Background Technology

[0002] Over the past century, engineering plastics have developed rapidly, greatly contributing to economic and manufacturing technological advancements. During this period, the plastics manufacturing industry has heavily relied on petrochemical resources. Functional resins play a crucial role in cutting-edge engineering fields such as aerospace, high-speed aircraft, and turbine engines. Consequently, bio-based epoxy resins have increasingly attracted the attention of researchers. However, currently, over 90% of the epoxy resin market share is dominated by bisphenol A glycidyl ether (DGEBA), a petroleum-based bisphenol A (BPA). Since BPA is considered an endocrine disruptor similar to estrogen, long-term BPA exposure may pose health risks and adverse effects on fetal development. Given the low stability and potential physiological toxicity of BPA and DGEBA, health and environmental concerns regarding the depletion of fossil fuels, and the long-term effects of these non-biodegradable materials, the need to develop harmless biomaterials is ultimately urgent.

[0003] Typically, biomass resources originate primarily from plant photosynthesis, resulting in high-molecular-weight raw materials such as lignin, cellulose, and hemicellulose. These are then used to produce bio-based chemicals through pyrolysis, coupling, and other catalytic processes. This ultimately leads to the production of a large number of sustainable epoxides based on biofurans, vanillin, eugenol, cashew nut shells, daidzein, itaconic acid, vegetable oils, rosin, and other oligomers. In particular, 5-hydroxymethylfurfural (HMF) has attracted significant attention due to its rich chemical properties and wide availability, and has been transformed into many high-value unit molecules. Consequently, it is also the only aromatic compound among the 12 most representative biomass platform molecules exclusively identified by the U.S. Department of Energy (DOE).

[0004] Regarding lignin, it is considered the only renewable source of aromatic compounds. However, over 150 million tons of lignin produced annually are discarded as waste from the pulp and paper industries. Although the eugenol building blocks produced by lignin depolymerization are very low (yield <0.2 wt%), the current lignin reserves on Earth are approximately 3 × 10⁻⁶ tons. 11 Metric tons, still awaiting high-value degradation. Commercial eugenol currently relies on cloves and cinnamon (content 20-90%). Due to its antibacterial, antioxidant, and flavoring properties, it has long been widely used in food and medicine, and is therefore also used as a natural preservative and flavoring agent, and is considered "Generally Recognized As Safe" (GRAS) by the U.S. Food and Drug Administration (FDA).

[0005] Compared to BPA, eugenol exhibits superior advantages in terms of continued accessibility and low toxicity. Some pioneering eugenol-based epoxy polymers demonstrate excellent performance in terms of processability, shape memory, degradation, and flame retardancy. Summary of the Invention

[0006] Purpose of the invention: The technical problem to be solved by the present invention is to provide an eugenol / furanyl resin monomer to address the shortcomings of the prior art.

[0007] Another technical problem to be solved by the present invention is to provide a method for preparing the above-mentioned eugenol / furanyl epoxy resin monomer.

[0008] Another technical problem to be solved by the present invention is to provide an eugenol / furanyl epoxy resin polymer prepared using the above-mentioned eugenol / furanyl epoxy resin monomer.

[0009] Another technical problem to be solved by the present invention is to provide a method for preparing the above-mentioned eugenol / furanyl epoxy resin polymer.

[0010] To address the first technical problem mentioned above, this invention discloses an eugenol / furanyl epoxy resin monomer as shown in formula DEF:

[0011]

[0012] To address the second technical problem mentioned above, this invention discloses a method for preparing eugenol / furanyl epoxy resin monomer DEF, comprising the following steps:

[0013] (1) CC coupling: Eugenol / furanyl biphenyl compound a was prepared by coupling the eugenol structure;

[0014] (2) Etherification reaction: 5-chloromethylfurfural (CMF) was grafted onto the hydroxyl groups at both ends of compound a using a catalyst to prepare compound b;

[0015] (3) Reduction reaction: The aldehyde groups at both ends of compound b are reduced to hydroxyl groups using a reducing agent to obtain compound c;

[0016] (4) Etherification reaction: Epichlorohydrin was grafted onto structure c under the action of a phase transfer catalyst to prepare eugenol / furanyl epoxy resin DEF.

[0017]

[0018] In step (1), the coupled eugenol structure a can be prepared according to existing technology, or it can be synthesized as follows: Eugenol is dissolved in a solvent, commercially available ammonia is added, and potassium ferricyanide saturated aqueous solution is slowly added dropwise. After stirring overnight, the solid obtained by filtration is compound a.

[0019] The solvent is any one or a combination of several of dichloromethane, ethyl acetate, acetonitrile, acetone, tetrahydrofuran, dioxane, and water; in one embodiment, the solvent is a mixture of acetone and water (volume ratio of 2:1); the mass-volume ratio of eugenol to ammonia is 1g:10-15mL; the concentration of ammonia is ≥25%; the molar ratio of eugenol to potassium ferricyanide is 1:0.8-1.2; and the reaction is carried out under stirring at a speed of 800-1000 rpm.

[0020] In step (2), the molar ratio of compound a to 5-chloromethylfurfural (CMF) is 1:2.2-3.

[0021] The catalyst mentioned in step (2) includes, but is not limited to, sodium iodide, potassium iodide, etc.; the molar ratio of the catalyst to a is 0.08-0.24:1.

[0022] The reaction temperature in step (2) is 50-100℃, preferably 80℃; the reaction time is 8-24h, preferably 16h.

[0023] The post-reaction treatment in step (2) involves diluting the reaction solution with water and an organic solvent and extracting it, followed by column chromatography purification. The solvents used include, but are not limited to, ethyl acetate, dichloromethane, and diethyl ether.

[0024] The reaction solvent in step (3) is a protic solvent, including any one or a combination of methanol, ethanol, and water. The concentration of compound b is 0.05-0.15 g / mL; the reducing agent in the reduction reaction is any one of sodium borohydride, lithium aluminum hydride, aluminum triisopropoxide, and hydrogen; the molar ratio of compound b to the reducing agent is 1:0.25-2.

[0025] The reaction temperature in step (3) is -10℃ to 10℃, preferably 0℃; the reaction time is 1-2h; after the reaction is completed, an appropriate amount of distilled water is added to quench the reaction and the compound c is purified.

[0026] The phase transfer catalyst used in step (4) includes, but is not limited to, one or a mixture of several of tetrabutylammonium bromide, tetraethylammonium bromide, and benzyltriethylammonium chloride.

[0027] The reaction in step (4) should first dissolve compound c in an organic solvent, and then add it to epichlorohydrin, an alkaline solution and a phase transfer catalyst; the organic solvent includes, but is not limited to, any one or a combination of dichloromethane, ethyl acetate, acetonitrile, acetone, tetrahydrofuran and dioxane, with tetrahydrofuran being preferred here; the alkaline solution is any one or a combination of potassium carbonate solution, sodium carbonate solution, sodium hydroxide solution and potassium hydroxide solution, with sodium hydroxide solution being preferred here.

[0028] In step (4), the molar ratio of the reaction compound c to epichlorohydrin, the base in the alkaline solution, and the phase transfer catalyst is 1:10-25:10-25:0.15-0.3.

[0029] The reaction temperature in step (4) is 40-60℃, preferably 50℃; the reaction time is 0.5-8h.

[0030] After the reaction described in step (4) is completed, the reaction solution is diluted with water, dried, filtered, and the solvent is removed from the filtrate under reduced pressure to obtain the eugenol / furanyl epoxy resin monomer DEF.

[0031] The eugenol / furanyl epoxy resin monomer DEF has an initial decomposition temperature of 254.3℃, a 30% decomposition temperature of 410.7℃, a maximum decomposition temperature of 274.4℃ / 445.3℃, and a char residue of 34.5% at 800℃.

[0032] Meanwhile, the viscosity of the eugenol / furanyl epoxy resin monomer DEF is low, at 506.3 cP at room temperature (25°C).

[0033] To address the third technical problem mentioned above, this invention discloses an eugenol / furanyl epoxy resin, which is a binary polymer I composed of A and B, or a binary polymer II composed of A and C.

[0034] The structural units shown in A, B, and C are respectively:

[0035]

[0036] Wherein, the binary polymer composed of A and B has a repeating structural unit as shown in Formula I, and the binary polymer composed of A and C has a repeating structural unit as shown in Formula II.

[0037]

[0038] Where m≥2, n≥2; m=2n.

[0039] To address the fourth technical problem mentioned above, this invention discloses a method for preparing the eugenol / furan epoxy resin. Specifically, the method involves mixing the eugenol / furan-based epoxy resin monomer DEF and an aryl sulfone diamine curing agent, stirring and heating until the mixture is uniformly melted, then pouring it into a mold and curing it at high temperature under an inert atmosphere to obtain a novel eugenol / furan-based epoxy resin.

[0040] The sulfone-based diamine curing mentioned above includes, but is not limited to, 4,4'-diaminodiphenyl sulfone (44DDS) and 3,3'-diaminoaminophenyl sulfone (33DDS).

[0041]

[0042] The molar ratio of the epoxy group of the eugenol / furanyl epoxy monomer to the amino group of the sulfone diamine curing agent is 0.8-1.5:1, preferably 0.8-1.2:1.

[0043] The melting temperature is 100-150℃, preferably 120-130℃; the curing temperature is 160-230℃, preferably 170-210℃.

[0044] The eugenol / furan epoxy resin prepared by the above method has an initial decomposition temperature of 295℃-320℃ in a nitrogen atmosphere, a char residue of 43%-53% at 800℃, a storage modulus of 2.0-3.5 GPa at room temperature, and a glass transition temperature of 90-150℃.

[0045] Beneficial effects: Compared with the prior art, the present invention has the following advantages:

[0046] (1) The present invention provides the structure and preparation method of a novel eugenol / furan bio-based epoxy resin monomer, which has a high degree of greenness in preparation process and is a novel dual bio-based composite epoxy monomer material;

[0047] (2) Eugenol and glycosyl 5-hydroxymethylfurfural in this invention can be obtained by bio-preparation methods from clove oil and biomass such as corn, wheat or straw, and the monomers have high biological added value.

[0048] (3) The novel epoxy monomer provided by the present invention has a low viscosity at room temperature;

[0049] (4) The epoxy resin with a novel structure is constructed using novel epoxy monomers in this invention, which has good thermal stability, mechanical properties and good biological safety.

[0050] (5) The novel epoxy resin provided by the present invention has a high char residue rate at 800℃. Attached Figure Description

[0051] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, and the advantages of the present invention in the above and / or other aspects will become clearer.

[0052] Figure 1 IR curve of epoxy monomer DEF;

[0053] Figure 2 TGA curve of epoxy monomer DEF;

[0054] Figure 3 IR curves for DEF / 44DDS and DEF / 33DDS;

[0055] Figure 4 IR curves of DGEBA / 44DDS and DGEBA / 33DDS;

[0056] Figure 5 TGA curves of polymers prepared in the examples and comparative examples;

[0057] Figure 6 Storage modulus curves of polymers prepared in the examples and comparative examples;

[0058] Figure 7 The glass transition temperature of the polymers prepared in the examples;

[0059] Figure 8 Overlap shear test of the prepared polymer. Detailed Implementation

[0060] Unless otherwise specified, the experimental methods described in the following examples are conventional methods; unless otherwise specified, the reagents and materials are commercially available.

[0061] This application provides a bisphenol structure of eugenol CC-coupled monomer, and synthesizes a novel eugenol / furan epoxy resin monomer through etherification / reduction / re-etherification. It also provides a method for preparing the epoxy resin of this monomer for constructing novel epoxy resin materials. The technical solution of this invention is described in detail below through specific embodiments.

[0062] Example 1: Preparation of compound a.

[0063] 10.5 g (64.0 mmol) of eugenol was added to a 500 mL flask and dissolved in acetone and water at a volume ratio of 2:1 (100 mL / 50 mL). The mixture was stirred until homogeneous, and then 70 mL of ammonia (25 wt%) was added. The mixture was stirred for 10 min. Then, 21.1 g of potassium ferricyanide (64.0 mmol, saturated aqueous solution) was added dropwise at a rate of 0.5 mL / min using a syringe pump. After the addition was complete, another 70 mL of ammonia was added, and the mixture was stirred overnight. After the reaction was complete, the solid was filtered off, and the filter cake was repeatedly washed with deionized water to obtain product a (10.2 g, yellow solid, yield 96.7%).

[0064]

[0065] 1 H NMR (400MHz, CDCl3) δ6.74 (dd, J=11.3, 1.8Hz, 4H), 6.07-5.93 (m, 2H), 5.16-5.02 (m, 4H), 3.90 (s, 6H), 3.36 (d, J=6.7Hz, 4H).

[0066] Example 2: Preparation of compound b.

[0067] Compound a (26.1 g, 80 mmol) was weighed into a 1000 mL flask and dissolved in 200 mL of acetonitrile. Potassium carbonate (26.5 g, 192 mmol) was added, and the mixture was stirred for 30 min. Then, CMF (27.6 g, 192 mmol) dissolved in 80 mL of acetonitrile was added dropwise to the system, along with sodium iodide (0.96 g, 6.4 mmol). The reaction was stirred at 80 °C, and TLC was monitored until the reaction was complete. The reaction solution was diluted with 200 mL of deionized water, and the organic phase was extracted with ethyl acetate (200 mL × 3). The combined organic phases were dried over anhydrous sodium sulfate, filtered, and the solvent was removed under reduced pressure. The product was purified by column chromatography (petroleum ether / ethyl acetate 4:1) to give pure product b (36.9 g, yellow viscous liquid, yield 85.2%).

[0068]

[0069] 1 H NMR(400MHz,Chloroform-d)δ9.50(s,2H),7.07(d,J=3.5Hz,2H),6.74(d,J=2.0Hz,2H),6.58(d,J=2.0Hz,2H),6.21(d, J=3.5Hz,2H),5.94(ddt,J=16.8,10.0,6.7Hz,2H),5.19-5.00(m,4H),4.89(s,4H),3.87(s,6H),3.32(d,J=6.7Hz,4H).

[0070] 13 C NMR (101MHz, CDCl3) δ177.80,158.25,152.31,152.21,143.19,137.16,135.99,132.56,122.92,116.09,111.99,111.38,66.61,55.87,39.99.

[0071] HRMS(ESI-TOF) m / z Calcd for C 32 H 30 NaO8[M+Na] + :565.1847,found:565.1833. Example 3 Preparation of compound c.

[0072] Compound b (32.5 g, 60 mmol) was dissolved in 200 mL of methanol, and sodium borohydride (2.3 g, 60 mmol) was added in two portions at 0 °C. The reaction was carried out for about 1 hour. After the reaction was completed by TLC monitoring, an appropriate amount of water was added to quench the reaction, and the organic phase was extracted with ethyl acetate. After drying with anhydrous sodium sulfate, the solution was filtered, concentrated under reduced pressure, and purified by column chromatography (petroleum ether / ethyl acetate 2:1) to give pure product c (26.3 g, yellow viscous liquid, yield 80.2%).

[0073]

[0074] 1 H NMR (400MHz, Chloroform-d) δ6.65(d,J=2.0Hz,2H),6.61(d,J=2.0Hz,2H),6.00(d,J=3.1Hz,2H),5.93(d,J=3. 0Hz,2H),5.91-5.83(m,2H),5.10-4.93(m,4H),4.66(s,4H),4.35(s,4H),3.79(s,6H),3.27(d,J=6.7,Hz,4H).

[0075] 13 C NMR (101MHz, CDCl3) δ154.06,152.68,151.36,143.44,137.42,135.39,132 .94,123.47,115.92,111.83,110.23,108.09,66.38,57.41,55.95,40.05.

[0076] HRMS(ESI-TOF) m / z Calcd for C 32 H 34 NaO8[M+Na]+: 569.2162, found: 569.2146. Example 4: Preparation of novel eugenol / furan epoxy resin monomer (DEF).

[0077] Epichlorohydrin (276.2 g, 3000 mmol), tetrabutylammonium bromide (3.7 g, 12 mmol), and sodium hydroxide aqueous solution (48.0 g, 1200 mmol, 50 wt%) were added to a 1000 mL flask. The mixture was stirred rapidly for 30 min, and the atmosphere was purged with nitrogen. Then, compound c (32.7 g, 60 mmol) was dissolved in 100 mL of tetrahydrofuran and slowly added dropwise to the reaction flask. The mixture was stirred at 50 °C and monitored by TLC until the reaction was complete. The reaction solution was diluted with 200 mL of deionized water, and the organic phase was extracted with ethyl acetate (200 mL × 3). After drying with anhydrous sodium sulfate, the solution was filtered, concentrated under reduced pressure, and purified by column chromatography (petroleum ether / ethyl acetate 4:1) to give the pure product DEF (36.5 g, yellow viscous liquid, yield 92.3%). This monomer has a low viscosity (506.3 cP, 100 rpm, 25 °C). Fourier transform infrared spectroscopy (FTIR) was performed as follows. Figure 1 As shown, the characteristic peak of the epoxy group is located at 845 cm⁻¹. -1 926cm -1 .

[0078] Viscosity testing method: Test temperature 25℃, sample volume 30mL, rotational viscometer model BROOKFIELDDV-2pro

[0079] Thermogravimetric analysis showed that the initial decomposition temperature in a nitrogen atmosphere was 254.3℃, the temperature at which 30% of the decomposition occurred was 410.7℃, the maximum decomposition temperature was 274.4℃ / 445.3℃, and the char residue at 800℃ was 34.5%.

[0080] Thermogravimetric analysis was performed on a TGA-550 system at temperatures ranging from 40 to 800°C, with a nitrogen flow rate of 20 mL / min and a heating rate of 20°C / min.

[0081]

[0082] 1 H NMR(400MHz,Chloroform-d)δ6.70(d,J=1.9,Hz,2H),6.65(d,J=2.0,Hz,2H),6.14(d,J=3.1Hz,2H),5.97 (d,J=3.1Hz,2H),5.96-5.87(m,2H),5.09-4.99(m,4H),4.72(s,4H),4.42-4.30(m,4H),3.83(s,6H),3.67 -3.62(m,2H),3.34-3.27(m,6H),3.06(ddt,J=5.8,4.2,2.9Hz,2H),2.72 -2.69(m,2H),2.52(dt,J=4.9,2.4Hz,2H).

[0083] 13 C NMR (101MHz, CDCl3) δ152.73,152.09,151.07,143.52,137.41,135.34,132.80,123. 43,115.83,111.97,110.27,110.05,70.49,66.47,65.14,55.97,50.7044.32,40.04.

[0084] HRMS(ESI-TOF) m / z Calcd for C 38 H 42 NaO 10 [M+Na] + :681.2683,found:681.2670.

[0085] Example 5: Preparation of polymer DEF / 44DDS.

[0086] In a reaction flask, DEF (3 mmol, 1.97 g) and curing agent 44DDS (1.5 mmol, 0.37 g) prepared in Example 4 were weighed and thoroughly mixed. The mixture was then slowly heated to 130°C until it melted and became clear and transparent. The mixture was then poured into a mold to cure the reaction. The temperature was then slowly increased to 170°C and stored at 170°C for 2 hours, 185°C for 1 hour, and 210°C for 1 hour. After that, the mixture was allowed to cool naturally to room temperature to obtain the polymer DEF / 44DDS.

[0087] Example 6 shows the preparation of the polymer DEF / 33DDS.

[0088] In a reaction flask, DEF (3 mmol, 1.97 g) and curing agent 33DDS (1.5 mmol, 0.37 g) prepared in Example 4 were weighed and thoroughly mixed. The mixture was then slowly heated to 130°C until it melted and became clear and transparent. The mixture was then poured into a mold to solidify and react. The temperature was then slowly increased to 165°C and stored at 165°C for 2 hours, 180°C for 1 hour, and 210°C for 1 hour. After that, the mixture was allowed to cool naturally to room temperature to obtain the polymer DEF / 33DDS.

[0089] Comparative Example 1: Preparation of polymer DGEBA / 44DDS.

[0090] In a reaction flask, weigh out bisphenol A diglyceride (DGEBA) (6 mmol, 2.04 g, from China Maclean Reagent Company) and curing agent 44DDS (3 mmol, 0.74 g), mix thoroughly, and slowly heat to 130°C until it melts and becomes clear and transparent. Then pour it into a mold to solidify the reaction, slowly heat to 170°C, and keep it at 170°C for 2 hours, 185°C for 1 hour, and 200°C for 1 hour. After that, let it cool naturally to room temperature to obtain the polymer DGEBA / 44DDS.

[0091] Comparative Example 2: Preparation of polymer DGEBA / 33DDS.

[0092] Weigh DGEBA (6 mmol, 2.04 g) and curing agent 33DDS (3 mmol, 0.74 g) into a reaction flask, mix thoroughly, and slowly heat to 130°C until it melts and becomes clear and transparent. Then pour it into a mold to cure the reaction, slowly heat to 165°C, and keep it at 165°C for 2 hours, 180°C for 1 hour, and 190°C for 1 hour. After that, let it cool naturally to room temperature under a nitrogen atmosphere to obtain the polymer DGEBA / 33DDS.

[0093] Infrared and thermogravimetric analyses were performed on the polymers prepared in Examples 5 and 6, as well as Comparative Examples 1 and 2.

[0094] Determined by infrared data, such as Figure 2 As shown, in the DEF system, the infrared absorption peaks of ethylene oxide in the original epoxy groups are (845 and 926 cm⁻¹). -1 The infrared absorption peak of the NH2 group in the curing agent DDS (1623 cm⁻¹) disappears and hardens. -1 (etc.), indicating that the epoxy groups and amine groups of the epoxy resin have completely polymerized; and the infrared peak of the C=C double bond in the olefin of the original epoxy substrate (1640 cm⁻¹) -1 The disappearance of equal-intensity stretching vibrations indicates that the vinyl groups in the system have completely self-polymerized. For example... Figure 3 As shown, in the DGEBA system, the infrared peaks of ethylene oxide in the original epoxy groups are at 860 and 912 cm⁻¹. -1 The infrared absorption peaks (1623 cm⁻¹) of NH₂ groups in the curing agent DDS during equal-intensity stretching vibration and constant-intensity stretching vibration are also observed. -1 The disappearance of the epoxy groups (etc.) indicates that the epoxy groups and amine groups of the epoxy resin have been completely polymerized.

[0095] Thermogravimetric analysis is performed as follows Figure 4 As shown, the initial decomposition temperature (T) of DEF / 44DDS d5 The initial decomposition temperature of DEF / 33DDS is 298.6℃, the maximum decomposition temperature is 279.4℃ / 419.6℃, and the char residue at 800℃ is 52.3%; d5The maximum thermal stability of DEF / 44DDS is 318.6℃, with a maximum decomposition temperature of 296.6℃ / 417.5℃ and a char residue of 44.2% at 800℃. Compared to DEF / 33DDS, DEF / 44DDS exhibits relatively weaker thermal stability. Compared to the comparative example, it has a higher char residue.

[0096] Thermogravimetric analysis (TGA) conditions: Thermogravimetric analysis was performed on a TGA-550 system at temperatures ranging from 40 to 800°C, with a nitrogen flow rate of 20 mL / min and a heating rate of 20°C / min.

[0097] The storage modulus of the examples and comparative examples was measured by dynamic thermomechanical analysis (DMA), and the results are as follows: Figure 5 As shown, at 30℃, DEF / 44DDS exhibits a higher storage modulus (2.1 GPa > 1.7 GPa) compared to DGEBA / 44DDS, and DEF / 33DDS exhibits a higher storage modulus (3.5 GPa > 2.4 GPa) compared to DGEBA / 33DDS. Therefore, the DEF system has certain advantages. DMA analysis results are as follows... Figure 6 As shown, the glass transition temperatures of the DEF / 44DDS polymer are 100.9℃ and 146.5℃, and the glass transition temperatures of the DEF / 33DDS polymer are 92.3℃ and 133.1℃.

[0098] DMA testing conditions: Under a nitrogen atmosphere, the temperature was scanned between 0 and 300°C using a single cantilever bending mode at a heating rate of 3°C / min. The sample dimensions were 10mm * 5mm * 3mm.

[0099] Overlap shear tests were performed on the examples and comparative examples, and the test results are as follows: Figure 7 As shown, DEF / 44DDS > DGEBA / 44DDS (19.5MPa > 18.2MPa), DEF / 33DDS > DGEBA / 33DDS (22.3MPa > 16.4MPa). The shear strength of the DEF system is better than that of the DGEBA system, with a maximum value reaching 27.9MPa.

[0100] Overlap shear test conditions: According to Chinese standard GB7124-86, the lap shear strength (LSS) of the bonded samples was measured at room temperature at a speed of 5 mm / min. The formula for calculating the shear strength (τ) is τ = N max / S, where N max S represents the maximum tensile force, and S represents the overlapping area.

[0101] This invention provides an eugenol / furanyl epoxy resin monomer, its preparation method, and its application. Many methods and approaches exist to achieve this technical solution; the above description is merely a preferred embodiment of the invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this invention, and these improvements and modifications should also be considered within the scope of protection of this invention. All components not explicitly stated in this embodiment can be implemented using existing technologies.

Claims

1. A eugenol / furan-based epoxy resin monomer, characterized in that: With the structure shown in DEF:

2. The method for preparing the eugenol / furanyl epoxy resin monomer according to claim 1, characterized in that: The following steps are involved: (1) CC coupling: using the coupling of eugenol structure to prepare eugenol / furanyl biphenyl compound a; (2) Etherification reaction: 5-chloromethylfurfural is grafted onto the hydroxyl groups at both ends of compound a using a catalyst to obtain compound b; (3) Reduction reaction: using a reducing agent to reduce the aldehyde groups at both ends of compound b to hydroxyl groups to obtain compound c; (4) Etherification reaction: epichlorohydrin is grafted onto compound c in the presence of a phase transfer catalyst to obtain eugenol / furanyl epoxy resin DEF.

3. The preparation method according to claim 2, characterized in that: In step (1), eugenol / furanylbiphenyl compound a is prepared by the following steps: dissolving eugenol in a solvent, then adding ammonia water, and slowly adding a saturated aqueous solution of potassium ferrocyanide, stirring overnight, and filtering the obtained solid to obtain compound a.

4. The preparation method according to claim 3, characterized in that: The solvent is any one or a combination of dichloromethane, ethyl acetate, acetonitrile, acetone, tetrahydrofuran, dioxane and water; the mass volume ratio of eugenol to ammonia water is 1g:10-15mL; the concentration of ammonia water is ≥25%; the molar ratio of eugenol to potassium ferrocyanide is 1:0.8-1.2; and the reaction is carried out under stirring at a rotation speed of 800-1000rpm.

5. The preparation method according to claim 2, characterized in that: In step (2), the molar ratio of compound a to 5-chloromethylfurfural is 1:2.2-3; the catalyst is sodium iodide or potassium iodide, and the molar ratio of the amount of the catalyst to a is 0.08-0.24:

1.

6. The preparation method according to claim 2, characterized in that: In step (2), the reaction temperature is 50-100° C.; the reaction time is 8-24 h; after the reaction is completed, the reaction solution is diluted with water and an organic solvent and extracted, and then purified by column chromatography.

7. The preparation method according to claim 2, characterized in that: In step (3), the reaction solvent is a protic solvent, the concentration of compound b is 0.05-0.15 g / mL; the reducing agent is any one of sodium borohydride, lithium aluminum hydride, aluminum triisopropoxide and hydrogen; and the molar ratio of compound b to the reducing agent is 1:0.25-2.

8. The preparation method according to claim 2, characterized in that: In step (3), the reaction temperature is -10°C-10°C; the reaction time is 1-2h; after the reaction is completed, an appropriate amount of distilled water is added to quench the reaction and purify to obtain compound c.

9. The preparation method according to claim 2, characterized in that: In step (4), compound c is first dissolved in an organic solvent and then added to a mixed solution of epichlorohydrin, an alkaline solution and a phase transfer catalyst for reaction, wherein the organic solvent is any one or a combination of dichloromethane, ethyl acetate, acetonitrile, acetone, tetrahydrofuran and dioxane; the alkaline solution is any one or a combination of potassium carbonate solution, sodium carbonate solution, sodium hydroxide solution and potassium hydroxide solution; the phase transfer catalyst is one or a mixture of tetrabutylammonium bromide, tetraethylammonium bromide and benzyltriethylammonium chloride; and the molar ratio of compound c to epichlorohydrin, the base in the alkaline solution and the phase transfer catalyst is 1:10-25:10-25:0.15-0.

3.

10. The preparation method according to claim 9, characterized in that: In step (4), the reaction temperature is 40-60° C., and the reaction time is 0.5-8 h. After the reaction is completed, the reaction solution is diluted with water and extracted, dried, filtered, and the filtrate is decompressed and the solvent is removed to purify the eugenol / furanyl epoxy resin monomer DEF.

11. Use of the eugenol / furanyl epoxy resin monomer according to claim 1 in preparing epoxy polymer materials.

12. A eugenol / furanyl-exchanged epoxy resin polymer, characterized in that: It is obtained by polymerizing structural units A and B or A and C, wherein the structural units A, B, and C are respectively: The binary polymer composed of A and B has a repeating structural unit shown in formula I, and the binary polymer composed of A and C has a repeating structural unit shown in formula II: Among them, m≥2, n≥2, m=2n.

13. The method for preparing the eugenol / furanyl-exchange epoxy resin polymer according to claim 12, characterized in that: The eugenol / furan-based epoxy resin monomer DEF and the aromatic sulfone diamine curing agent described in claim 1 are mixed and melted and then injection molded for curing to obtain a eugenol / furan-based epoxy resin polymer, wherein the aromatic sulfone diamine curing agent is 4,4'-diaminodiphenyl sulfone or 3,3'-diaminodiphenyl sulfone.

14. The preparation method according to claim 13, characterized in that: The molar ratio of the epoxy group in the eugenol / furan epoxy resin monomer DEF to the amino group in the aromatic sulfone diamine curing agent is 0.8-1.5:1; the melting temperature is 100-150°C; and the curing temperature is 160-230°C.

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