A high-strength and high-toughness flame-retardant synergistic epoxy resin composition for prepreg and a preparation method thereof
Patent Information
- Application Number
- CN202610761727.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-05-29
- Publication Date
- 2026-08-21
AI Technical Summary
[0003]目前，预浸料树脂的力学强度的来源是多官能环氧，然而提高多官能团树脂占比虽然可提高力学强度，但会降低韧性，且由于反应活性高带来的大量的热释放，会降低树脂的阻燃性能；同步提高多官环氧和阻燃剂用量，则会牺牲树脂韧性，无法实现增韧增强与阻燃性能的协同发挥
（1）本发明方法制得的环氧树脂组合物100℃下粘度为10~40 P，适用于模压成型工艺，可在70-90℃下加工为预浸料，预浸料在125±5℃条件下固化。
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Abstract
Description
Technical Field
[0001] This invention belongs to the field of polymer materials technology, specifically relating to a high-strength, high-toughness, flame-retardant, synergistic epoxy resin composition for prepregs and its preparation method. Background Technology
[0002] With the increasing demands for lightweighting and functional integration in aerospace equipment, the application of composite materials has expanded from primary load-bearing structures to a large number of non-load-bearing / secondary load-bearing components (such as interior trim, cargo hold liners, radomes, and corrosion-resistant insulation layers). This field has certain requirements for the flame retardancy, dielectric properties, and impact resistance of materials, but is extremely cost-sensitive—that is, it needs to minimize material and manufacturing costs while meeting airworthiness and safety standards. Among these, high-resin-content prepregs (40-50%) sacrifice some non-essential mechanical properties in exchange for significant cost optimization across the entire material, flame retardancy, and process chain, representing the optimal solution for non-load-bearing components that is both "sufficient and economical." Given the increasingly stringent cost control requirements of domestically produced large aircraft and transport aircraft, researching high-resin-content glass fiber prepregs is a key technological path to achieving a balance between low cost, lightweighting, and airworthiness and safety. Simultaneously, reducing reliance on imported high-end, low-resin-content prepregs can further reduce supply chain costs and ensure self-sufficiency and controllability.
[0003] Currently, the mechanical strength of prepreg resins comes from multifunctional epoxy resins. However, while increasing the proportion of multifunctional resins can improve mechanical strength, it will reduce toughness. Furthermore, the large amount of heat released due to high reactivity will reduce the flame retardant properties of the resin. Simultaneously increasing the amount of multifunctional epoxy resins and flame retardants will sacrifice the toughness of the resin, making it impossible to achieve a synergistic effect of toughening and flame retardant properties. Current research has found that the core contradictions that the existing technology of prepreg resins has not resolved include: (1) the structural contradiction of increasing the proportion of multifunctional epoxy resins and decreasing toughness: In the existing technology, increasing the proportion of multifunctional epoxy resins (such as phenolic epoxy and glycidylamine epoxy) is the main means to improve mechanical strength. However, the high crosslinking density and high molecular chain rigidity of multifunctional epoxy resins will inevitably lead to a decrease in toughness; (2) the formulation contradiction of adding flame retardants and losing mechanical properties: Traditional physical blending methods (such as alumina, bromine-containing compounds, etc.) require the addition of 30-60% flame retardants. As a non-reactive filler, the flame retardant will block the crosslinking of epoxy resins. Network continuity leads to a decrease in compressive modulus and interlaminar shear strength; although phosphorus-based flame retardants can improve compatibility, studies have shown that while new flame retardants such as phosphorus-containing ionic liquids improve flame retardancy, they still have difficulty avoiding negative impacts on glass transition temperature and mechanical properties; (3) High resin content prepreg - the problem of balancing process performance and mechanical properties: High resin content (usually >40%) prepregs are in urgent demand in the aerospace and rail transportation fields, but increasing the resin content will exacerbate the heat release during the curing process, leading to a deterioration in flame retardant performance; at the same time, it is difficult to control the resin flow under high resin content, and defects of poor or rich resin are easy to occur. Existing patents mostly focus on viscosity control, but have not made synergistic designs for the triple goals of "high resin content + high strength and high toughness + flame retardancy". Therefore, how to maintain high strength and high toughness mechanical properties of high resin content prepregs has become an urgent problem to be solved. Summary of the Invention
[0004] To address the problems existing in the background technology, the present invention provides a high-strength, high-toughness, flame-retardant, and synergistic epoxy resin composition for high resin content prepregs and its preparation method. The present invention achieves for the first time a ternary synergy of "high multifunctional epoxy content + high flame retardant efficiency + high toughness". That is, through a unique synergistic formulation design, while maintaining the high crosslinking density of multifunctional epoxy resin (ensuring high strength), a reactive flame-retardant and toughening component is introduced, so that the flame-retardant element participates in the network construction rather than simply physical filling, thereby breaking through the traditional understanding that "increasing strength must sacrifice toughness".
[0005] To achieve the above-mentioned objectives, the present invention adopts the following technical solution: This invention introduces inorganic nanoparticles (such as fumed silica) to prepolymerize with the matrix epoxy resin to form nanoparticle-modified epoxy resin. The nanoparticle-modified epoxy resin is then prepolymerized with special engineering plastics to synergistically enhance and toughen the resin system. Furthermore, macromolecular rubber particles with active groups are introduced and grafted onto the epoxy resin for prepolymerization, thereby regulating the molecular crosslinking network and improving the peel strength of the resin system. Based on the previous two formulation designs, flame retardants suitable for prepreg epoxy resin systems are screened, their surfaces are pretreated, and after grafting with a silane coupling agent, they are prepolymerized with the matrix epoxy resin. This allows for the achievement of flame retardancy requirements in the resin system with only a small amount of addition, while maintaining high flame retardancy with almost no reduction in toughness during the resin curing process.
[0006] A high-strength, high-toughness, flame-retardant, synergistic epoxy resin composition for prepregs, comprising the following components in parts by weight: 50-80 parts of nanoparticle-modified epoxy resin, 15-30 parts of multifunctional epoxy resin 8-15 parts toughening agent 8-20 parts flame retardant 5-8 parts of curing agent Accelerator 2-5 parts; The nanoparticle-modified epoxy resin comprises the following components by mass percentage: Bisphenol A type liquid epoxy resin I 37%~50%, 1%~10% phenolic epoxy resin Alicyclic epoxy resin 1%~10%, Inorganic nanoparticles 35%~45%, Silane coupling agent I 1%~3%, The rest are bisphenol A type solid epoxy resin. The sum of the mass percentages of all components is 100%. The toughening agent comprises the following components by mass percentage: Specialty engineering plastics 10%~20%, Macromolecular rubber 30%~50%, The rest are nanoparticle-modified epoxy resins. The sum of the mass percentages of all components is 100%. The flame retardant comprises the following components by mass percentage: Phosphorus-based flame retardants 50%~60%, Silane coupling agent II 30%~40%, The rest are bisphenol A type liquid epoxy resin II. The sum of the mass percentages of all components is 100%.
[0007] This invention uses nanoparticle-modified epoxy resin as the matrix epoxy resin, which has excellent high strength, high toughness and flame retardant properties, and can prepare a high-performance epoxy resin system suitable for molding process to manufacture aerospace structural parts.
[0008] Furthermore, both the bisphenol A type liquid epoxy resin I and the bisphenol A type liquid epoxy resin II are independently selected from any one or a mixture of more than one of E-51 and E-54; The bisphenol A type solid epoxy resin is selected from any one or a mixture of more than one of NPES-901, NPES-909, E-12, and E-20; The phenolic epoxy resin is selected from any one or a mixture of one or more of 638S, 704H, and JF45. The alicyclic epoxy resin is selected from any one or a mixture of more than one of S-182, S-184, and TDE-85; The inorganic nanoparticles are fumed silica with a specific surface area of 180~220m² / g. Both silane coupling agent I and silane coupling agent II are independently selected from any one or a mixture of one or more of KH550, KH560, and KH792.
[0009] Furthermore, the multifunctional epoxy resin is selected from any one or a mixture of more than one of AG80 and AFG90; The special engineering plastics are selected from any one or a mixture of more than one of PES, PES-C, PEEK, PEK-C, PVF-C, and PVB; The macromolecular rubber is selected from any one or a mixture of more than one of CTBN, ATBN, MX-150, MX-154, MX-160, MX-170, MX-414, and MX-451.
[0010] Furthermore, the phosphorus-based flame retardant is selected from any one or a mixture of more than one of modified 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), ammonium polyphosphate, and aluminum diethylphosphonate.
[0011] Furthermore, the curing agent is selected from any one or a mixture of more than one of dicyandiamide and organic hydrazide; The accelerator is selected from any one or a mixture of one or more of the following: modified imidazole, organic urea UR200, UR300, UR400, and UR500.
[0012] Furthermore, the present invention also provides a method for preparing a high-strength, high-toughness, flame-retardant, synergistic epoxy resin composition for prepregs, comprising the following steps: (1) Preparation of nanoparticle modified epoxy resin: Bisphenol A type liquid epoxy resin I, bisphenol A type solid epoxy resin, phenolic epoxy resin, alicyclic epoxy resin, inorganic nanoparticles, and silane coupling agent I are prepolymerized and mixed in a double planetary reactor for 0.5~3h to obtain nanoparticle modified epoxy resin. The temperature of the dual planetary reactor is set to 120~150℃, the stirring speed is set to 25~45rpm, and the dispersion speed is set to 2000~3500rpm; (2) Preparation of toughening agent: Nanoparticle modified epoxy resin and macromolecular rubber were prepolymerized and mixed in a double planetary reactor at 120~150℃ for 1~2h. The stirring speed in the double planetary reactor was set to 25~45rpm and the dispersion speed was set to 500~1000rpm. Then, special engineering plastics were added, and the temperature of the double planetary reactor was raised to 150~180℃. The stirring speed was set to 25~45rpm and the dispersion speed was set to 1500~2500rpm. The mixing reaction time was 1~2h. (3) Preparation of flame retardant: The phosphorus flame retardant was mixed with silane coupling agent II and bisphenol A type liquid epoxy resin II and then dispersed at high speed under vacuum at room temperature to obtain the flame retardant. The dispersion speed was 1000~2000 rpm, the vacuum degree was 0.85 bar, and the high-speed dispersion time was 20~30 min. Furthermore, after high-speed dispersion in step (3), the product is then ground 2-4 times using a three-roll mill to obtain a flame retardant; (4) Preparation of epoxy resin composition: Nanoparticle modified epoxy resin, toughening agent, flame retardant and multifunctional epoxy resin are mixed at 100~120℃ for 1~2h, then cooled to 60~80℃, curing agent and accelerator are added, stirred for 10~20min, and discharged through roller 2~4 times to obtain the epoxy resin composition.
[0013] Furthermore, the present invention also provides an application of the above-mentioned epoxy resin composition in prepreg, specifically, the epoxy resin composition is compounded with glass fiber fabric to obtain glass fiber prepreg, and the resin content is controlled at 45±3%.
[0014] The above-mentioned prepreg is conventionally laid, cured, and machined to obtain composite material samples.
[0015] This epoxy resin matrix possesses excellent high strength, high toughness, and flame retardant properties. This invention provides a high-performance epoxy resin system suitable for molding processes in the fabrication of aerospace structural components.
[0016] Compared with the prior art, the present invention has the following beneficial effects: (1) The epoxy resin composition prepared by the method of the present invention has a viscosity of 10~40 P at 100℃, which is suitable for compression molding process. It can be processed into prepreg at 70-90℃ and the prepreg is cured at 125±5℃.
[0017] (2) The cured product of the epoxy resin composition prepared by the present invention has a Tg ≥ 130℃, a compressive strength > 420MPa, a roller peel strength ≥ 13Nmm / mm, a burning length ≤ 140mm, a compression modulus increase of 15%~25%, and an interlayer peel increase of 10%~20%, which proves that the system can still maintain an excellent mechanical-flame retardant balance under high resin content conditions, filling the gap of the prior art. Detailed Implementation
[0018] The present invention will be further described below with reference to specific embodiments.
[0019] A high-strength, high-toughness, flame-retardant, synergistic epoxy resin composition for prepregs, comprising the following components in parts by weight: 50-80 parts of nanoparticle-modified epoxy resin, 15-30 parts of multifunctional epoxy resin 8-15 parts toughening agent 8-20 parts flame retardant 5-8 parts of curing agent Accelerator 2-5 parts; The nanoparticle-modified epoxy resin comprises the following components by mass percentage: Bisphenol A type liquid epoxy resin I 37%~50%, 1%~10% phenolic epoxy resin Alicyclic epoxy resin 1%~10%, Inorganic nanoparticles 35%~45%, Silane coupling agent I 1%~3%, The rest are bisphenol A type solid epoxy resin. The sum of the mass percentages of all components is 100%. The toughening agent comprises the following components by mass percentage: Specialty engineering plastics 10%~20%, Macromolecular rubber 30%~50%, The rest are nanoparticle-modified epoxy resins. The sum of the mass percentages of all components is 100%. The flame retardant comprises the following components by mass percentage: Phosphorus-based flame retardants 50%~60%, Silane coupling agent II 30%~40%, The rest are bisphenol A type liquid epoxy resin II. The sum of the mass percentages of all components is 100%.
[0020] This invention uses nanoparticle-modified epoxy resin as the matrix epoxy resin, which has excellent high strength, high toughness and flame retardant properties, and can prepare a high-performance epoxy resin system suitable for molding process to manufacture aerospace structural parts.
[0021] Furthermore, both the bisphenol A type liquid epoxy resin I and the bisphenol A type liquid epoxy resin II are independently selected from any one or a mixture of more than one of E-51 and E-54; The bisphenol A type solid epoxy resin is selected from any one or a mixture of more than one of NPES-901, NPES-909, E-12, and E-20; The phenolic epoxy resin is selected from any one or a mixture of one or more of 638S, 704H, and JF45. The alicyclic epoxy resin is selected from any one or a mixture of more than one of S-182, S-184, and TDE-851; The inorganic nanoparticles are fumed silica with a specific surface area of 180~220m² / g. Both silane coupling agent I and silane coupling agent II are independently selected from any one or a mixture of one or more of KH550, KH560, and KH792.
[0022] Furthermore, the multifunctional epoxy resin is selected from any one or a mixture of more than one of AG80 and AFG90; The special engineering plastics are selected from any one or a mixture of more than one of PES, PES-C, PEEK, PEK-C, PVF-C, and PVB; The macromolecular rubber is selected from any one or a mixture of more than one of CTBN, ATBN, MX-150, MX-154, MX-160, MX-170, MX-414, and MX-451.
[0023] Furthermore, the phosphorus-based flame retardant is selected from any one or a mixture of more than one of modified 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), ammonium polyphosphate, and aluminum diethylphosphonate.
[0024] Furthermore, the curing agent is selected from any one or a mixture of more than one of dicyandiamide and organic hydrazide; The accelerator is selected from any one or a mixture of one or more of the following: modified imidazole, organic urea UR200, UR300, UR400, and UR500.
[0025] Furthermore, the present invention also provides a method for preparing a high-strength, high-toughness, flame-retardant, synergistic epoxy resin composition for prepregs, comprising the following steps: (1) Preparation of nanoparticle modified epoxy resin: Bisphenol A type liquid epoxy resin I, bisphenol A type solid epoxy resin, phenolic epoxy resin, alicyclic epoxy resin, inorganic nanoparticles, and silane coupling agent I are prepolymerized and mixed in a double planetary reactor for 0.5~3h to obtain nanoparticle modified epoxy resin. The temperature of the dual planetary reactor is set to 120~150℃, the stirring speed is set to 25~45rpm, and the dispersion speed is set to 2000~3500rpm; (2) Preparation of toughening agent: Nanoparticle modified epoxy resin and macromolecular rubber were prepolymerized and mixed in a double planetary reactor at 120~150℃ for 1~2h. The stirring speed in the double planetary reactor was set to 25~45rpm and the dispersion speed was set to 500~1000rpm. Then, special engineering plastics were added, and the temperature of the double planetary reactor was raised to 150~180℃. The stirring speed was set to 25~45rpm and the dispersion speed was set to 1500~2500rpm. The mixing reaction time was 1~2h. (3) Preparation of flame retardant: The phosphorus flame retardant was mixed with silane coupling agent II and bisphenol A type liquid epoxy resin II and then dispersed at high speed under vacuum at room temperature to obtain the flame retardant. The dispersion speed was 1000~2000 rpm, the vacuum degree was 0.85 bar, and the high-speed dispersion time was 20~30 min. Furthermore, after high-speed dispersion in step (3), the product is then ground 2-4 times using a three-roll mill to obtain a flame retardant; (4) Preparation of epoxy resin composition: Nanoparticle modified epoxy resin, toughening agent, flame retardant and multifunctional epoxy resin are mixed at 100~120℃ for 1~2h, then cooled to 60~80℃, curing agent and accelerator are added, stirred for 10~20min, and discharged through roller 2~4 times to obtain the epoxy resin composition.
[0026] Furthermore, the present invention also provides an application of the above-mentioned epoxy resin composition in prepreg, specifically, the epoxy resin composition is compounded with glass fiber fabric to obtain glass fiber prepreg, and the resin content is controlled at 45±3%.
[0027] The above-mentioned prepreg is conventionally laid, cured, and machined to obtain composite material samples.
[0028] Example 1 The embodiment describes a high-strength, high-toughness, flame-retardant, synergistic epoxy resin composition for prepregs and its preparation method. The raw materials for preparation include the following components in parts by weight: 65 parts of nanoparticle modified epoxy resin (self-made), 20 parts of multifunctional epoxy resin, 10 parts of toughening agent (self-made), 15 parts of flame retardant (self-made), 6 parts of curing agent, and 3 parts of accelerator. The nanoparticle-modified epoxy resin comprises the following components by mass percentage: E-51 (45%), 704H (1%), S-184 (5%), nano silica (40%), KH550 (2%), and the remainder is NPES-901. The toughening agent comprises the following components by mass percentage: PES (8%), PES-C (7%), CTBN (40%), and the remainder is nanoparticle-modified epoxy resin. The flame retardant comprises the following components by weight percentage: ammonium polyphosphate (35%), aluminum diethylphosphinate (20%), KH560 (35%), and the remainder being E-54; The multifunctional epoxy resin comprises the following components by weight percentage: AG80 (50%) and AFG90 (50%). The curing agent comprises the following components by weight percentage: dicyandiamide (100%). The accelerator comprises the following components by weight percentage: organic urea UR400 (90%) and modified imidazole (10%).
[0029] A method for preparing a high-strength, high-toughness, flame-retardant, synergistic epoxy resin composition for prepregs includes the following steps: (1) Preparation of nanoparticle modified epoxy resin: Bisphenol A type liquid epoxy resin I, bisphenol A type solid epoxy resin, phenolic epoxy resin, alicyclic epoxy resin, inorganic nanoparticles, and silane coupling agent I are prepolymerized and mixed in a double planetary reactor for 2 hours to obtain nanoparticle modified epoxy resin. The temperature of the double planetary reactor is set to 130℃, the stirring speed is set to 35rpm, and the dispersion speed is set to 2500rpm. (2) Preparation of toughening agent: Nanoparticle modified epoxy resin and macromolecular rubber were prepolymerized and mixed in a double planetary reactor at 135℃ for 1.5h. The stirring speed in the double planetary reactor was set to 35rpm and the dispersion speed was set to 800rpm. Then special engineering plastics were added, the temperature of the double planetary reactor was raised to 160℃, the stirring speed was set to 35rpm and the dispersion speed was set to 2000rpm, and the mixing reaction time was 1h. (3) Preparation of flame retardant: The phosphorus flame retardant was mixed with silane coupling agent II and bisphenol A type liquid epoxy resin II and then dispersed at high speed under vacuum at room temperature to obtain the flame retardant. The dispersion speed was 1500 rpm, the vacuum degree was 0.85 bar, and the high-speed dispersion time was 25 min. After high-speed dispersion in step (3), the product is then ground three times with a three-roll mill to obtain the flame retardant; (4) Preparation of epoxy resin composition: Nanoparticle modified epoxy resin, toughening agent, flame retardant and multifunctional epoxy resin are mixed at 110°C for 1.5h, then cooled to 70°C, curing agent and accelerator are added, stirred for 15min, and discharged through rollers 3 times to obtain the epoxy resin composition.
[0030] Example 2 The embodiment describes a high-strength, high-toughness, flame-retardant, synergistic epoxy resin composition for prepregs and its preparation method. The raw materials for preparation include the following components in parts by weight: 50 parts of nanoparticle modified epoxy resin (self-made), 30 parts of multifunctional epoxy resin, 15 parts of toughening agent (self-made), 20 parts of flame retardant (self-made), 8 parts of curing agent, and 2 parts of accelerator. The nanoparticle-modified epoxy resin comprises the following components by mass percentage: E-54 (37%), 638S (3%), S-182 (10%), nano silica (45%), KH550 (2%), KH792 (1%), and the remainder is E20. The toughening agent comprises the following components by weight percentage: PEEK (5%), PEK-C (5%), MX154 (50%), and the remainder is nanoparticle-modified epoxy resin; The flame retardant comprises the following components by mass percentage: DOPO (50%), KH560 (20%), KH550 (10%), and the remainder is E-51; The multifunctional epoxy resin comprises the following components by weight percentage: AG80 (30%) and AFG90 (70%). The curing agent comprises the following components by weight percentage: dicyandiamide (90%) and organic hydrazide (10%). The accelerator comprises the following components by weight percentage: organic urea UR200 (20%) and UR500 (80%).
[0031] A method for preparing a high-strength, high-toughness, flame-retardant, synergistic epoxy resin composition for prepregs includes the following steps: (1) Preparation of nanoparticle modified epoxy resin: Bisphenol A type liquid epoxy resin I, bisphenol A type solid epoxy resin, phenolic epoxy resin, alicyclic epoxy resin, inorganic nanoparticles, and silane coupling agent I were prepolymerized and mixed in a double planetary reactor for 0.5 h to obtain nanoparticle modified epoxy resin. The temperature of the double planetary reactor is set to 120℃, the stirring speed is set to 45rpm, and the dispersion speed is set to 3500rpm. (2) Preparation of toughening agent: Nanoparticle modified epoxy resin and macromolecular rubber were prepolymerized and mixed in a double planetary reactor at 120℃ for 2 hours. The stirring speed in the double planetary reactor was set to 45 rpm and the dispersion speed was set to 1000 rpm. Then, special engineering plastics were added, the temperature of the double planetary reactor was raised to 150℃, the stirring speed was set to 25 rpm and the dispersion speed was set to 1500 rpm, and the mixing reaction time was 2 hours. (3) Preparation of flame retardant: The phosphorus flame retardant was mixed with silane coupling agent II and bisphenol A type liquid epoxy resin II and then dispersed at high speed under vacuum at room temperature to obtain the flame retardant. The dispersion speed was 2000 rpm, the vacuum degree was 0.85 bar, and the high-speed dispersion time was 20 min. Furthermore, after high-speed dispersion in step (3), the product is then ground three times with a three-roll mill to obtain a flame retardant; (4) Preparation of epoxy resin composition: Nanoparticle modified epoxy resin, toughening agent, flame retardant and multifunctional epoxy resin are mixed at 120°C for 1 h, then cooled to 80°C, curing agent and accelerator are added, stirred for 10 min, and discharged through rollers 3 times to obtain the epoxy resin composition.
[0032] Example 3 The embodiment describes a high-strength, high-toughness, flame-retardant, synergistic epoxy resin composition for prepregs and its preparation method. The raw materials for preparation include the following components in parts by weight: 80 parts of nanoparticle modified epoxy resin (self-made), 15 parts of multifunctional epoxy resin, 8 parts of toughening agent (self-made), 8 parts of flame retardant (self-made), 5 parts of curing agent, and 5 parts of accelerator. The nanoparticle-modified epoxy resin comprises the following components by mass percentage: E-54 (50%), JF45 (10%), TDE-85 (1%), nano silica (35%), KH550 (1%), and the remainder is NPES-909. The toughening agent comprises the following components by weight percentage: PVB (5%), PEK-C (5%), PES (10%), MX-170 (30%), and the remainder is nanoparticle-modified epoxy resin. The flame retardant comprises the following components by weight percentage: ammonium polyphosphate (40%), aluminum diethylphosphonate (20%), KH560 (15%), KH550 (15%), and the remainder is E-51; The multifunctional epoxy resin comprises the following components by weight percentage: AG80 (40%) and AFG90 (60%). The curing agent comprises the following components by weight percentage: dicyandiamide (100%). The accelerator comprises the following components by weight percentage: organic urea UR200 (50%) and UR500 (50%).
[0033] A method for preparing a high-strength, high-toughness, flame-retardant, synergistic epoxy resin composition for prepregs includes the following steps: (1) Preparation of nanoparticle modified epoxy resin: Bisphenol A type liquid epoxy resin I, bisphenol A type solid epoxy resin, phenolic epoxy resin, alicyclic epoxy resin, inorganic nanoparticles, and silane coupling agent I are prepolymerized and mixed in a double planetary reactor for 3 hours to obtain nanoparticle modified epoxy resin. The temperature of the double planetary reactor is set to 150℃, the stirring speed is set to 25rpm, and the dispersion speed is set to 2000rpm. (2) Preparation of toughening agent: Nanoparticle modified epoxy resin and macromolecular rubber were prepolymerized and mixed in a double planetary reactor at 150℃ for 1 h. The stirring speed in the double planetary reactor was set to 25 rpm and the dispersion speed was set to 500 rpm. Then, special engineering plastics were added, the temperature of the double planetary reactor was raised to 180℃, the stirring speed was set to 45 rpm and the dispersion speed was set to 2500 rpm, and the mixing reaction time was 1 h. (3) Preparation of flame retardant: The phosphorus flame retardant was mixed with silane coupling agent II and bisphenol A type liquid epoxy resin II and then dispersed at high speed under vacuum at room temperature to obtain the flame retardant. The dispersion speed was 1000 rpm, the vacuum degree was 0.85 bar, and the high-speed dispersion time was 30 min. Furthermore, after high-speed dispersion in step (3), the product is then ground three times with a three-roll mill to obtain a flame retardant; (4) Preparation of epoxy resin composition: Nanoparticle modified epoxy resin, toughening agent, flame retardant and multifunctional epoxy resin are mixed at 100°C for 2 hours, then cooled to 60°C, curing agent and accelerator are added, stirred for 20 minutes, and discharged through rollers 3 times to obtain the epoxy resin composition.
[0034] Comparative Example 1 The difference between Comparative Example 1 and Example 1 is that inorganic nanoparticles are not introduced, that is, the nanoparticle-modified epoxy resin lacks inorganic nanoparticles, and the inorganic nanoparticles are replaced by an equal amount of bisphenol A type liquid epoxy resin.
[0035] Comparative Example 2 The difference between Comparative Example 2 and Example 1 is that the self-made toughening agent is entirely composed of macromolecular rubber.
[0036] Comparative Example 3 The difference between Comparative Example 3 and Example 1 is that the self-made toughening agent is entirely composed of special engineering plastics.
[0037] Comparative Example 4 The difference between Comparative Example 4 and Example 1 is that the homemade flame retardant does not contain a coupling agent.
[0038] Performance testing The performance test results of the epoxy resin compositions in each embodiment and comparative example are shown in Table 1.
[0039]
[0040] Table 1. Viscosity test results of the examples and comparative examples. The data in Table 1 show that the epoxy resin composition prepared by the method of the present invention has a viscosity of 1000~4000 mPa·s at 100℃, which is suitable for compression molding process.
[0041] Application Examples The epoxy resin compositions of each embodiment and comparative example were respectively compounded with fiberglass fabric to obtain fiberglass prepregs, with the resin content controlled at 45±3%. The prepregs were then subjected to conventional laying, curing (the entire mold was placed in an autoclave, heated to 115~145℃ at a vacuum degree <-0.095 MPa, at a heating rate of 0.5~2°C / min, with a pressure of 0.3~0.6 MPa, held at that temperature for 1~2 hours, and then cooled to room temperature for molding), and machining to obtain composite samples. Performance tests were conducted on the composite samples obtained in each embodiment and comparative example, and the results are shown in Table 2.
[0042] Table 2. Performance test results of composites prepared using the epoxy resin compositions of each example and comparative example.
[0043] The data in Table 2 shows that: The prepregs prepared using the epoxy resin composition of this invention, after curing, all meet the requirements of Tg≥130℃, with significantly higher compressive strength and roller peel strength, flammable material length≤140mm, compression modulus increased by 15%~25%, and interlayer peel increased by 10%~20%, proving that the system can still maintain excellent mechanical-flame retardant balance under high resin content conditions.
Claims
1. A high-strength, high-toughness, flame-retardant, synergistic epoxy resin composition for prepregs, characterized in that, Its raw materials include the following components in parts by weight: 50-80 parts of nanoparticle-modified epoxy resin, 15-30 parts of multifunctional epoxy resin 8-15 parts toughening agent 8-20 parts flame retardant 5-8 parts of curing agent Accelerator 2-5 parts; The nanoparticle-modified epoxy resin comprises the following components by mass percentage: Bisphenol A type liquid epoxy resin I 37%~50%, 1%~10% phenolic epoxy resin Alicyclic epoxy resin 1%~10%, Inorganic nanoparticles 35%~45%, Silane coupling agent I 1%~3%, The rest are bisphenol A type solid epoxy resin. The sum of the mass percentages of all components is 100%. The toughening agent comprises the following components by mass percentage: Specialty engineering plastics 10%~20%, Macromolecular rubber 30%~50%, The rest are nanoparticle-modified epoxy resins. The sum of the mass percentages of all components is 100%. The flame retardant comprises the following components by mass percentage: Phosphorus-based flame retardants 50%~60%, Silane coupling agent II 30%~40%, The rest are bisphenol A type liquid epoxy resin II. The sum of the mass percentages of all components is 100%.
2. The high-strength, high-toughness, flame-retardant, synergistic epoxy resin composition for prepregs according to claim 1, characterized in that, Both the bisphenol A type liquid epoxy resin I and the bisphenol A type liquid epoxy resin II are independently selected from any one or a mixture of one or more of E-51 and E-54; The bisphenol A type solid epoxy resin is selected from any one or a mixture of one or more of NPES-901, NPES-909, E-12, and E-20; The phenolic epoxy resin is selected from any one or a mixture of one or more of 638S, 704H, and JF45. The alicyclic epoxy resin is selected from any one or a mixture of more than one of S-182, S-184, and TDE-85; The inorganic nanoparticles are fumed silica with a specific surface area of 180~220m² / g. The silane coupling agent I and silane coupling agent II are each independently selected from any one or a mixture of one or more of KH550, KH560, and KH792.
3. The high-strength, high-toughness, flame-retardant, synergistic epoxy resin composition for prepregs according to claim 1, characterized in that, The multifunctional epoxy resin is selected from any one or a mixture of one or more of AG80 and AFG90.
4. The high-strength, high-toughness, flame-retardant, synergistic epoxy resin composition for prepregs according to claim 1, characterized in that, The special engineering plastic is selected from any one or a mixture of more than one of PES, PES-C, PEEK, PEK-C, PVF-C, and PVB; The macromolecular rubber is selected from any one or a mixture of more than one of CTBN, ATBN, MX-150, MX-154, MX-160, MX-170, MX-414, and MX-451.
5. The high-strength, high-toughness, flame-retardant, synergistic epoxy resin composition for prepregs according to claim 1, characterized in that, The phosphorus-based flame retardant is selected from any one or a mixture of more than one of the following: modified 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, ammonium polyphosphate, and aluminum diethylphosphonate.
6. The high-strength, high-toughness, flame-retardant, synergistic epoxy resin composition for prepregs according to claim 1, characterized in that, The curing agent is selected from dicyandiamide, organic hydrazide, or a mixture of one or more of them; The accelerator is selected from any one or a mixture of one or more of the following: modified imidazole, organic urea UR200, UR300, UR400, and UR500.
7. A method for preparing a high-strength, high-toughness, flame-retardant, synergistic epoxy resin composition for prepregs according to any one of claims 1 to 5, characterized in that, Includes the following steps: (1) Preparation of nanoparticle modified epoxy resin: Bisphenol A type liquid epoxy resin I, bisphenol A type solid epoxy resin, phenolic epoxy resin, alicyclic epoxy resin, inorganic nanoparticles, and silane coupling agent I are prepolymerized and mixed in a double planetary reactor for 0.5~3h to obtain nanoparticle modified epoxy resin. (2) Preparation of toughening agent: Nanoparticle modified epoxy resin and macromolecular rubber were prepolymerized and mixed in a double planetary reactor at 120~150℃ for 1~2h. The stirring speed in the double planetary reactor was set to 25~45rpm and the dispersion speed was set to 500~1000rpm. Then special engineering plastics were added, and the double planetary reactor was heated to 150~180℃. The stirring speed was set to 25~45rpm and the dispersion speed was set to 1500~2500rpm. The mixing reaction time was 1~2h. (3) Preparation of flame retardant: The phosphorus flame retardant was mixed with silane coupling agent II and bisphenol A type liquid epoxy resin II and then dispersed at high speed under vacuum at room temperature to obtain the flame retardant. The dispersion speed was 1000~2000 rpm, the vacuum degree was 0.85 bar, and the high-speed dispersion time was 20~30 min. (4) Preparation of epoxy resin composition: Nanoparticle modified epoxy resin, toughening agent, flame retardant and multifunctional epoxy resin are mixed at 100~120℃ for 1~2h, then cooled to 60~80℃, curing agent and accelerator are added, stirred for 10~20min, and discharged through roller 2~4 times to obtain the epoxy resin composition.
8. The preparation method according to claim 6, characterized in that, In step (1), the temperature of the double planetary reactor is set to 120~150℃, the stirring speed is set to 25~45rpm, and the dispersion speed is set to 2000~3500rpm; After high-speed dispersion in step (3), the product is then ground 2 to 4 times with a three-roll mill to obtain the flame retardant.
9. The use of the epoxy resin composition according to any one of claims 1 to 5 in a prepreg.
10. The application according to claim 9, characterized in that, The epoxy resin composition is compounded with glass fiber fabric to obtain glass fiber prepreg, with the resin content controlled at 45±3%.