Phenolic aldehyde composite material with high impact toughness and preparation method thereof

Abstract

The invention discloses a phenolic composite material with high impact toughness and a preparation method thereof, and belongs to the technical field of resin-based composite materials. The preparation method comprises the following steps: mixing phenolic resin and porous particles, and carrying out ultrasonic dispersion to obtain a premix; adding a flexibilizer into the premix, stirring and grinding to obtain a mixture; coating release paper with the mixture, covering the release paper with the reinforced fibers subjected to constant-temperature treatment, and performing hot-pressing impregnation to obtain a prepreg; and finally, cutting, laying, curing and forming to obtain the phenolic aldehyde composite material. According to the invention, the porous polyimide particles are adopted as the interlayer toughening agent and have a synergistic effect with the liquid nitrile rubber, so that the impact toughness of the composite material is remarkably improved, the layering damage is inhibited, and meanwhile, the high modulus, heat resistance and flame retardance of the material are kept. The composite material is suitable for the fields of aviation, rail transit, ships and the like, and is particularly suitable for structural parts and interior parts with high impact toughness requirements.

Description

Technical Field

[0001] This invention belongs to the field of resin-based composite material technology, specifically relating to a high-impact-resistant and tough phenolic composite material and its preparation method. Background Technology

[0002] Fiber-reinforced resin matrix composites have been widely used due to their high specific strength and specific stiffness, excellent fatigue fracture resistance, and customizable structures, such as in the main load-bearing components of aircraft wings and fuselages in the aerospace industry. The main obstacle to the effective application of composite materials is their delamination tendency. When materials are subjected to impacts, such as drops, hail, and gravel, severe invisible delamination damage can form within the laminate, causing a significant decrease in the strength and stiffness of the composite structure, thus limiting further improvements in the application level of composite materials. Therefore, how to suppress delamination damage and improve the impact damage resistance and delamination resistance of composite materials is of great practical significance. Currently, the toughness of resin matrix composites is mainly evaluated through the following methods, including compressive strength after impact (CAI), gamma, ... Ⅰ C (Type I fracture strain energy release rate), G ⅠⅠ C (Type I fracture strain energy release rate), open-pore compressive strength (OHC), open-pore tensile strength (OHT), and initial edge delamination strength (EDT) are among the properties of composite materials. Among them, CAI properties are closely related to the actual application of advanced composite materials in aerospace, and are therefore widely recognized by researchers.

[0003] The structural integrity and dimensional stability of phenolic resins at high temperatures, along with the density of the pyrolytic carbon layer, make them widely applicable in ablation protection and flame-retardant materials. Phenolic resin composites, prepared from phenolic resins, possess high specific strength and stiffness, flame retardancy, heat resistance, and ablation resistance, and are widely used in aerospace and public transportation interiors, brakes, bulletproofing, and marine applications. However, due to the highly cross-linked network structure and the lack of fiber reinforcement in the thickness direction of prepreg composites, the interlaminar properties of phenolic resin laminates are far lower than their in-plane properties. Under external impact, the laminate material is highly susceptible to delamination failure, significantly reducing the mechanical properties of the composite material and shortening its service life.

[0004] To improve the impact toughness of phenolic prepreg composites, the main approach is resin matrix toughening. However, due to the weak interface between the reinforcing fibers and the resin matrix, and the constraint effect of the interlaminar thickness of the reinforcing fibers on the deformation of the resin matrix and the propagation of microcrack tips, the significant toughening effect of matrix toughening cannot be effectively transferred to continuously reinforced composites. Furthermore, interlaminar toughening is also frequently used to improve the interlaminar toughness of prepregs, but it requires comprehensive consideration of the introduction method of the interlaminar toughening agent, the interaction between the resin and the toughening agent, and its impact on the overall material properties. Currently, research on interlaminar toughening of phenolic resin-based composites is limited.

[0005] Therefore, how to prepare a phenolic resin-based prepreg that combines high modulus, heat resistance, and high impact toughness is one of the problems that needs to be solved. Summary of the Invention

[0006] In view of the above-mentioned prior art, the present invention provides a high impact toughness phenolic composite material and its preparation method, which solves the problem that the prior art cannot simultaneously possess high modulus, heat resistance and high impact toughness.

[0007] To achieve the above objectives, the technical solution adopted by this invention is: to provide a method for preparing a high-impact toughness phenolic composite material, comprising the following steps: S1: Phenolic resin is mixed with porous microparticles and then ultrasonically dispersed to obtain a premix; S2: Add toughening agent to premix, mix and stir, then grind to obtain mixture; S3: Coat the mixture onto the release paper, then cover the surface of the mixture with reinforcing fibers that have been treated at a constant temperature and hot-press impregnate it to obtain a prepreg; S4: Cut the prepreg and lay it in a mold to cure and form a high-impact toughness phenolic composite material.

[0008] Furthermore, the mass ratio of phenolic resin to porous microparticles is 10:1.

[0009] Furthermore, the phenolic resin is a solvent-free phenolic resin with a solid content >80 wt% and a viscosity of 500~10000 cP / 50℃.

[0010] Furthermore, the porous microparticles are polyimide microspheres, which are prepared through the following steps: Weigh out pyromellitic dianhydride, 4,4'-diaminodiphenyl ether, PS microspheres, and N-methylpyrrolidone in a mass ratio of 1.1:1:3.1:2.1. Under ice bath conditions, pyromellitic dianhydride and 4,4'-diaminodiphenyl ether are added sequentially to N-methylpyrrolidone and reacted for 24 h. Then, PS microspheres are added to the solution and sonicated for 30 min using an ultrasonic cell disruptor to obtain a uniform dispersion. The dispersion is then slowly added to a solution containing 4% Span-80 liquid paraffin and stirred at 300 rpm for 2 h. Pyridine and acetic anhydride are then added in a volume ratio of 1:1, and the mixture is heated to 80 °C and refluxed for 4 h. Finally, the mixture is heated under an inert atmosphere at a rate of 150 °C / 60 min + 300 °C / 90 min, with a heating rate of 1... Thermal imidization was carried out at ℃ / min, and PI / PS microspheres were obtained after cooling. Finally, the PI / PS microspheres were dispersed in toluene, stirred overnight at room temperature, washed with ethanol, and vacuum dried at 120 ℃ for 12 h to obtain polyimide microspheres.

[0011] Furthermore, the polyimide microspheres have a particle size of 8~120 μm, a pore size of 0.1~10 μm, and a sphericity >80%.

[0012] Furthermore, the toughening agent is liquid nitrile rubber, and its addition amount is 5-8% of the mass of phenolic resin.

[0013] Furthermore, in S2, the mixing and stirring are carried out at 35~60℃ and 50~300 r / min for 5~60 min, and the grinding is carried out 1~5 times using a three-roll mill with a roller gap of 0.01~0.1mm.

[0014] Furthermore, the coating in S3 is applied on one or both sides, with a coating amount of 50~400 g / m². 2 The coating temperature is 30~80 ℃, the coating speed is 1~10 m / min; the constant temperature treatment temperature of the reinforcing fiber is 25~110 ℃, the hot pressing impregnation temperature is 25~60 ℃, and the hot pressing pressure is 0.1~0.5 MPa.

[0015] Furthermore, the curing process in S4 is carried out using an autoclave molding process, with a temperature of 60~180 ℃, a pressure of 1~10 bar, and a time of 2~20 h.

[0016] The present invention also provides a method for preparing a high impact toughness phenolic composite material.

[0017] The beneficial effects of this invention are as follows: The preparation method provided by this invention optimizes process parameters such as ultrasonic dispersion, three-roll milling, coating temperature, fiber heat treatment, and hot-press impregnation, achieving directional enrichment of porous microparticles between layers and uniform resin impregnation. Furthermore, the porous polyimide microparticles prepared using the template method possess uniform pore size (0.1~10 μm) and high sphericity (>80%). Their porous structure increases the specific surface area, allowing for thorough wetting of the phenolic resin and the formation of a strong interfacial bond. Upon impact, cracks can extend into the microparticles, lengthening the crack path. The porous structure may also undergo plastic collapse under load, further absorbing energy and achieving a more efficient toughening effect. Simultaneously, the porous polyimide itself possesses high modulus, excellent heat resistance, and flame retardancy. It forms an interpenetrating network structure with the phenolic resin, enhancing toughness without affecting the material's original rigidity and thermal stability.

[0018] Experimental data show that the composite material of this invention achieves a significant improvement in the compressive strength (CAI) of phenolic composites through the synergistic toughening effect of porous polyimide microparticles and liquid nitrile rubber. In the examples, the CAI value reaches 298 MPa, far exceeding the 146 MPa of the comparative pure phenolic system. This is because the porous polyimide microparticles are enriched in the interlaminar region, effectively hindering crack propagation through mechanisms such as crack pinning, path deflection, and shear banding. Simultaneously, the liquid nitrile rubber forms an island structure in the matrix, absorbing impact energy through crazing and shear deformation. This dual toughening mechanism significantly improves the material's impact toughness and resistance to delamination damage. Furthermore, the flexural modulus of the composite material remains above 128 GPa, and the glass transition temperature (Tg) is maintained at around 207℃, indicating that this invention significantly improves toughness without sacrificing the material's stiffness and heat resistance.

[0019] In summary, the preparation method provided by this invention has a stable and controllable process route, which is suitable for continuous industrial production. The phenolic composite material prepared by this method has the characteristics of high impact resistance, high modulus, heat resistance and flame retardancy, and can be widely used in fields with high requirements for the comprehensive performance of materials, such as aviation, rail transportation, ships, and bulletproof equipment. It is especially suitable for structural parts and interior parts that are susceptible to impact, and has important engineering application value and market potential. Attached Figure Description

[0020] Figure 1 This is a flowchart of the preparation process. Detailed Implementation

[0021] The specific embodiments of the present invention will be described in detail below with reference to examples.

[0022] Example 1 A method for preparing a high-impact-resistant and tough phenolic composite material, the preparation process of which is as follows: Figure 1 As shown, it includes the following steps: S1: Weigh pyromellitic dianhydride, 4,4'-diaminodiphenyl ether, PS microspheres, and N-methylpyrrolidone in a mass ratio of 1.1:1:3.1:2.1. Under ice bath conditions, pyromellitic dianhydride and 4,4'-diaminodiphenyl ether are added sequentially to N-methylpyrrolidone and reacted for 24 h. Then, PS microspheres are added to the solution and ultrasonically treated for 30 min using an ultrasonic cell disruptor to obtain a uniform dispersion. The dispersion is then slowly added to liquid paraffin containing 4% Span-80 and stirred at 300 rpm for 2 h. Pyridine and acetic anhydride are then added in a volume ratio of 1:1, and the mixture is heated to 80 °C and refluxed for 4 h. Finally, the mixture is heated under a nitrogen atmosphere at a rate of 150 °C / 60 min + 300 °C / 90 min, with a heating rate of 1... Thermal imidization was carried out at ℃ / min, and PI / PS microspheres were obtained after cooling. Finally, the PI / PS microspheres were dispersed in toluene, stirred overnight at room temperature, washed with ethanol, and vacuum dried at 120 ℃ for 12 h to obtain polyimide microspheres. Phenolic resin (solvent-free phenolic resin with solid content of 96 wt% and viscosity of 2700 cP / 50℃) and polyimide microspheres (particle size of 8~120 μm, pore size of 0.1~10 μm, sphericity >80%) were weighed at a mass ratio of 10:1 and stirred and sonicated at 35 ℃ for 30 min to obtain a premix. S2: Add liquid nitrile rubber accounting for 7 wt% of phenolic resin to the premix, stir for 30 min at a temperature of 50 ℃ and a speed of 100 r / min, then add the mixture to a three-roll mill and grind it 3 times at a gap of 0.01 mm to obtain the mixture; S3: Coat the mixture onto the surface of the release paper (using double-sided coating, coating temperature of 55 ℃, coating rate of 5 m / min), with a coating amount of 133 g / m. 2 Then, unidirectional carbon fibers are treated at 80 ℃ and covered on the surface of the mixture. Finally, after hot pressing and impregnation at 45 ℃ and 0.1 MPa, the impregnation is removed and a PE mesh film is laid to obtain the prepreg. S4: Cut the prepreg and lay it in the mold. After filling it into a vacuum bag, pre-extract it at room temperature for 12 hours at less than -0.095 MPa. Then cure it at 80 ℃ and 0 bar for 2 hours, then at 100 ℃ and 5 bar for 2 hours, then at 130 ℃ and 7 bar for 2 hours, and finally at 170 ℃ and 9 bar for 3 hours to obtain a high impact toughness phenolic composite material.

[0023] Example 2 A method for preparing a high-impact-resistant and tough phenolic composite material, the preparation process of which is as follows: Figure 1 As shown, it includes the following steps: S1: Pyromellitic dianhydride, 4,4'-diaminodiphenyl ether, and N-methylpyrrolidone were weighed in a mass ratio of 1.1:1:2.1. Pyromellitic dianhydride and 4,4'-diaminodiphenyl ether were added sequentially to N-methylpyrrolidone under ice bath conditions and reacted for 24 h. PS microspheres were then added to the solution and sonicated for 30 min using an ultrasonic cell disruptor to obtain a uniform dispersion. The dispersion was then slowly added to liquid paraffin containing 4% Span-80 and stirred at 300 rpm for 2 h. Pyridine and acetic anhydride were then added in a volume ratio of 1:1, and the mixture was heated to 80 °C and refluxed for 4 h. Thermal imidization was then carried out under a nitrogen atmosphere at a temperature of 150 °C / 60 min + 300 °C / 90 min with a heating rate of 1 °C / min. After cooling, PI microspheres were obtained. Finally, the PI microspheres were dispersed in toluene and stirred overnight at room temperature. After washing with ethanol, the mixture was then heated at 120 °C. Vacuum drying at ℃ for 12 h yields polyimide microspheres; phenolic resin (solvent-free phenolic resin with a solid content of 90wt% and a viscosity of 9000 cP / 50℃) and polyimide microspheres (particle size of 8~120 μm, pore size of 0.1~10 μm, sphericity >80%) are weighed at a mass ratio of 10:1, and stirred and sonicated at 35 ℃ for 30 min to obtain a premix; S2: Add liquid nitrile rubber accounting for 5 wt% of phenolic resin to the premix, stir for 5 min at a temperature of 50 ℃ and a speed of 300 r / min, then add the mixture to a three-roll mill and grind it 5 times at a gap of 0.1 mm to obtain the mixture; S3: Coat the mixture onto the surface of the release paper (using single-sided coating, coating temperature of 30 ℃, coating speed of 1m / min), with a coating amount of 50 g / m. 2 Then, unidirectional carbon fibers are treated at a constant temperature of 25 ℃ and covered on the surface of the mixture. Finally, after hot pressing and impregnation at 25 ℃ and 0.5 MPa, the impregnation is removed and covered with a PE mesh film to obtain the prepreg. S4: Cut the prepreg and lay it in the mold. After filling it into a vacuum bag, pre-extract it at room temperature for 12 hours at less than -0.095 MPa. Then cure it at 80 ℃ and 0 bar for 2 hours, then at 100 ℃ and 5 bar for 2 hours, then at 130 ℃ and 7 bar for 2 hours, and finally at 170 ℃ and 9 bar for 3 hours to obtain a high impact toughness phenolic composite material.

[0024] Example 3 A method for preparing a high-impact-resistant and tough phenolic composite material includes the following steps: S1: Weigh pyromellitic dianhydride, 4,4'-diaminodiphenyl ether, PS microspheres, and N-methylpyrrolidone in a mass ratio of 1.1:1:3.1:2.1. Under ice bath conditions, pyromellitic dianhydride and 4,4'-diaminodiphenyl ether are added sequentially to N-methylpyrrolidone and reacted for 24 h. Then, PS microspheres are added to the solution and ultrasonically treated for 30 min using an ultrasonic cell disruptor to obtain a uniform dispersion. The dispersion is then slowly added to liquid paraffin containing 4% Span-80 and stirred at 300 rpm for 2 h. Pyridine and acetic anhydride are then added in a volume ratio of 1:1, and the mixture is heated to 80 °C and refluxed for 4 h. Finally, the mixture is heated under a nitrogen atmosphere at a rate of 150 °C / 60 min + 300 °C / 90 min, with a heating rate of 1... Thermal imidization was carried out at ℃ / min, and PI / PS microspheres were obtained after cooling. Finally, the PI / PS microspheres were dispersed in toluene, stirred overnight at room temperature, washed with ethanol, and vacuum dried at 120 ℃ for 12 h to obtain polyimide microspheres. Phenolic resin (solvent-free phenolic resin with solid content of 96 wt% and viscosity of 500 cP / 50℃) and polyimide microspheres (particle size of 8~120 μm, pore size of 0.1~10 μm, sphericity >80%) were weighed at a mass ratio of 10:1 and stirred and sonicated at 35 ℃ for 30 min to obtain a premix. S: Coat the premixed material onto the surface of the release paper (using double-sided coating, coating temperature of 80 ℃, coating speed of 10m / min), with a coating amount of 400 g / m. 2 Then, unidirectional carbon fibers are subjected to isothermal treatment at 100 ℃ and then covered on the surface of the mixture. Finally, after hot pressing and impregnation at 60 ℃ and 0.1 MPa, the impregnation is removed and a PE mesh film is laid to obtain the prepreg. S3: Cut the prepreg and lay it in the mold, put it into a vacuum bag and pre-vacuum at room temperature for 12 hours at less than -0.095 MPa, then cure it at 80 ℃ and 0 bar for 2 hours, then at 100 ℃ and 5 bar for 2 hours, then at 130 ℃ and 7 bar for 2 hours, and finally at 170 ℃ and 9 bar for 3 hours to obtain a high impact toughness phenolic composite material.

[0025] Example 4 A method for preparing a high-impact-resistant and tough phenolic composite material includes the following steps: S1: Add liquid nitrile rubber accounting for 7 wt% of phenolic resin to phenolic resin (solvent-free phenolic resin with a solid content of 96 wt% and a viscosity of 2700 cP / 50℃), stir for 30 min at a temperature of 50℃ and a speed of 100 r / min, and then add the mixture to a three-roll mill and grind it 3 times with a gap of 0.01 mm to obtain a mixture; S2: Coat the mixture onto the surface of the release paper (using double-sided coating, coating temperature of 55 ℃, coating rate of 5 m / min), with a coating amount of 133 g / m. 2 Then, unidirectional carbon fibers are treated at 80 ℃ and covered on the surface of the mixture. Finally, after hot pressing and impregnation at 45 ℃ and 0.1 MPa, the impregnation is removed and a PE mesh film is laid to obtain the prepreg. S3: Cut the prepreg and lay it in the mold, put it into a vacuum bag and pre-vacuum at room temperature for 12 hours at less than -0.095 MPa, then cure it at 80 ℃ and 0 bar for 2 hours, then at 100 ℃ and 5 bar for 2 hours, then at 130 ℃ and 7 bar for 2 hours, and finally at 170 ℃ and 9 bar for 3 hours to obtain a high impact toughness phenolic composite material.

[0026] Comparative Example 1 A phenolic composite material includes the following steps: S1: Phenolic resin (solvent-free phenolic resin with a solid content of 96 wt% and a viscosity of 2700 cP / 50℃) was baked at 70℃ for 2 hours and then coated onto the surface of release paper (double-sided coating was used, coating temperature was 55℃, and coating rate was 5 m / min), with a coating amount of 133 g / m. 2 Then, unidirectional carbon fibers are treated at 80 ℃ and covered on the surface of the mixture. Finally, after hot pressing and impregnation at 45 ℃ and 0.1 MPa, the impregnation is removed and a PE mesh film is laid to obtain the prepreg. S2: Cut the prepreg and lay it in a mold. After filling it into a vacuum bag, pre-vacuum it at room temperature for 12 hours at less than -0.095 MPa. Then cure it at 80 ℃ and 0 bar for 2 hours, then at 100 ℃ and 5 bar for 2 hours, then at 130 ℃ and 7 bar for 2 hours, and finally at 170 ℃ and 9 bar for 3 hours to obtain the phenolic composite material.

[0027] Experimental Example The composite materials prepared in Examples 1-4 and the comparative example were tested, and the results are shown in Table 1. The pure phenolic resin composite material had the lowest CAI value and poor impact toughness. The composite material toughened only by liquid rubber showed a certain improvement in impact toughness, but the Tg of the system decreased significantly. Compared with liquid rubber toughening, interlaminar toughening using polyimide had a more significant effect on improving CAI. This is because by enriching polyimide in the interlaminar region where it is more prone to failure, energy dissipation mechanisms such as crack pinning and path deflection are specifically used to greatly inhibit the propagation of delamination, while there is no loss in Tg and flexural modulus. The composite material obtained by combining liquid rubber with porous polyimide exhibits the best CAI performance, indicating a significant improvement in the system's impact resistance. This is because the combination of matrix toughening and interlayer toughening enhances the system's energy dissipation mechanism, leading to improved overall performance. Compared to porous polyimide, solid polyimide particles have a lower CAI value. This is because porous polyimide has interconnected pores, and its larger specific surface area makes its interaction with phenolic resin stronger. Crack propagation or particle pull-out requires more energy, and cracks can extend into the particle interior, further prolonging the crack path. In addition, under impact loads, the porous structure of porous polyimide may undergo plastic collapse to absorb energy. Combined with multiple energy dissipation mechanisms, this ultimately results in the system having the best impact toughness.

[0028] Table 1 Statistical Table of Composite Material Performance Tests

[0029] While specific embodiments of the present invention have been described in detail, they should not be construed as limiting the scope of protection of this patent. Various modifications and variations that can be made by those skilled in the art without inventive effort within the scope described in the claims still fall within the scope of protection of this patent.

Claims

1. A method for producing a high impact strength phenolic composite material, characterized by, It comprises the following steps: S1: mixing phenolic resin with porous microparticles and then performing ultrasonic dispersion to obtain a premix; S2: adding a toughening agent to the premix, mixing and stirring, and then grinding to obtain a mixture; S3: coating the mixture on a release paper, covering the surface of the mixture with a constant-temperature treated reinforcing fiber, and hot-pressing to obtain a prepreg; S4: cutting the prepreg and laying it in a mold for curing and molding to obtain a high-impact toughness phenolic composite material.

2. The method for preparing the high impact resistance and toughness phenolic composite material according to claim 1, characterized in that: The mass ratio of the phenolic resin to the porous microparticles is 10:

1.

3. The method for preparing the high impact resistance and toughness phenolic composite material according to claim 1, characterized in that: The phenolic resin is a solvent-free phenolic resin with a solid content of >80 wt% and a viscosity of 500-10000 cP / 50℃.

4. The method for preparing the high impact resistance and toughness phenolic composite material according to claim 1, characterized in that, The porous microparticles are polyimide microspheres prepared by the following steps: Take 1.1:1:3.1:2.1 of pyromellitic dianhydride, 4,4'-diamino diphenyl ether, PS microspheres, and N-methyl pyrrolidone by mass ratio; add pyromellitic dianhydride and 4,4'-diamino diphenyl ether to N-methyl pyrrolidone under ice bath conditions, and react for 24 h; then add PS microspheres to the solution, and use an ultrasonic cell crusher to ultrasonically treat for 30 min to obtain a uniform dispersion liquid; then slowly add the dispersion liquid to a liquid paraffin containing 4% Span-80, stir at 300 rpm for 2 h, then add pyridine and acetic anhydride in a volume ratio of 1:1, heat to 80℃, and reflux for 4 h; then perform thermal imidization in an inert atmosphere at 150℃ / 60min+300℃ / 90min, with a heating rate of 1℃ / min; after cooling, PI / PS microspheres are obtained; finally, disperse the PI / PS microspheres in toluene, stir overnight at room temperature, wash with ethanol, and vacuum dry at 120℃ for 12 h to obtain polyimide microspheres.

5. The method for preparing the high impact resistance and toughness phenolic composite material according to claim 4, characterized in that: The particle size of the polyimide microspheres is 8-120 μm, the pore size is 0.1-10 μm, and the sphericity is >80%.

6. The method for preparing the high impact resistance and toughness phenolic composite material according to claim 1, characterized in that: The toughening agent is liquid nitrile rubber, and the addition amount is 5-8% of the mass of the phenolic resin.

7. The method for preparing the high impact resistance and toughness phenolic composite material according to claim 1, characterized in that: The mixing and stirring in S2 is stirring at 50-300 r / min for 5-60 min at 35-60℃, and the grinding is grinding 1-5 times using a three-roll grinder with a roll gap of 0.01-0.1 mm.

8. The method for preparing the high impact resistance and toughness phenolic composite material according to claim 1, characterized in that: The coating in the S3 is single-sided or double-sided, with a coating amount of 50-400 g / m 2 , a coating temperature of 30-80 DEG C, a coating speed of 1-10 m / min; the reinforcing fiber constant temperature treatment temperature is 25-110 DEG C, the hot-pressing impregnation temperature is 25-60 DEG C, and the hot-pressing pressure is 0.1-0.5 MPa.

9. The method for preparing the high impact resistance and toughness phenolic composite material according to claim 1, characterized in that: The curing and molding in S4 is a hot press molding process, with a temperature of 60-180℃, a pressure of 1-10 bar, and a time of 2-20 h.

10. A high-impact toughness phenolic composite material prepared by the method of any one of claims 1-9.

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