Phenolic resin-based composite material for subway tunnel evacuation platform

Abstract

The invention provides a phenolic resin-based composite material for a subway tunnel evacuation platform, and relates to the technical field of composite materials for subway tunnel construction, the phenolic resin-based composite material comprises the following raw materials by weight: 35-40 parts of glass fiber twistless roving, 5-10 parts of modified phenolic resin, 0.4-0.7 part of a curing agent, 0.4-0.7 part of an accelerator, 0.1-0.3 part of a coupling agent, 0.1-0.3 part of a release agent, 1-1.5 parts of industrial methanol, 0.1-0.3 part of a nano filler, and 0.5-1 part of pure water. Wherein the modified phenolic resin is synthesized by the following steps; the preparation method comprises the following steps: S1, adding phenol and organic silicon into a reactor in a nitrogen atmosphere, adding a catalyst, and heating for reaction to prepare a first intermediate; s2, adding NaOH into the first intermediate to adjust the pH value of the reaction system, and adding formaldehyde to prepare a second intermediate; and S3, adding NaOH into the second intermediate to adjust the pH value of the reaction system, adding melamine and ethidene diamine, and carrying out heating reaction to obtain the modified phenolic resin. The composite material obtained by the invention has better bearing capacity, heat resistance and lasting flame retardance.

Description

Technical Field

[0001] The present invention relates to the technical field of composite materials for subway tunnel construction, and more specifically, to a phenolic resin-based composite material for subway tunnel evacuation platforms. Background Art

[0002] An evacuation platform refers to a dedicated passage for evacuating passengers set in the subway interval tunnel. As an important fire evacuation facility, the evacuation platform has high requirements for the strength and fire resistance of materials. RPC materials have characteristics such as high strength, high toughness, and high durability, and are suitable for subway evacuation platforms, solving many problems such as the stress, durability, and aesthetics of subway evacuation platforms. RPC materials are mainly composed of ultra-fine reactive powder, high-quality quartz sand, cement, mineral admixtures, high-strength fibers, etc. However, this kind of concrete evacuation platform has poor corrosion resistance and weak flexural strength. During actual operation, due to the influence of natural conditions such as stray current corrosion, humidity immersion, and frost heaving at the tunnel entrance, its own performance will gradually age, the strength will gradually decrease, and there will be risks such as cracking and chipping. There is a high probability of major train operation safety hazards such as foreign objects falling off in the track area. Moreover, once a fire occurs in the interval, passengers may be secondarily injured, posing a greater safety hazard.

[0003] In recent years, resin-based composite evacuation platforms, as new materials, have been widely used in more than 10 subways in Beijing, Shanghai, Guangzhou, Nanjing, Changchun, etc. due to their performance advantages such as high strength, good insulation, and strong acid and alkali corrosion resistance. The composite evacuation platform uses phenolic resin as the matrix material and glass fiber roving as the reinforcing material, and is made by the pultrusion process. It is mainly composed of platform pedals, brackets, handrails, stairways, and other components, and is installed in the subway tunnel or elevated line after being assembled by special connectors. However, since glass fiber yarn is an inorganic material, its compatibility with the phenolic resin (polymer) matrix is poor and it is difficult to disperse evenly, thus affecting the mechanical properties of the composite board; the glass fiber-reinforced phenolic resin-based composite material with a high resin content can meet the integrity requirements after 1 hour of fire resistance, but cannot meet the load-bearing performance requirements, and due to its high resin content, it cannot meet the A2 fire rating requirements, that is, it is difficult for the composite material to meet the high requirements of the subway tunnel evacuation platform for the board in terms of bearing capacity and flame retardancy after fire resistance.

[0004] The prior art with the publication number CN115124811A discloses a composite board for subway tunnel evacuation platforms, which comprises the following raw materials in parts by weight: 30-42 parts of glass fiber roving, 4-10 parts of phenolic resin, 0.3-0.6 parts of curing agent, 0.2-0.5 parts of coupling agent, 1.6-2.4 parts of flame retardant, 0.3-0.7 parts of release agent, 0.8-2 parts of industrial methanol, 0.3-0.8 parts of iron oxide, and 0.4-1 part of water. The flame retardant used in the prior art contains phosphorus harmful substances. Although the -OH in the flame retardant can form hydrogen bonds with the phenolic hydroxyl groups on the molecular chain of phenolic resin, the hydrogen bond binding force is weak. After long-term use of this composite board, the flame retardant migrates or precipitates, resulting in a decline in the flame retardant performance of the board; the existing glass fiber roving is only treated with a coupling agent, and the fiber and resin rely on a single chemical bond, so the interfacial binding force between the fiber and resin is weak and the bearing capacity is low. Summary of the Invention

[0005] In view of this, the present invention aims to provide a phenolic resin-based composite material for subway tunnel evacuation platforms. It is intended to solve the problems that although the -OH in the flame retardant in the prior art can form hydrogen bonds with the phenolic hydroxyl groups on the molecular chain of phenolic resin, the hydrogen bond binding force is weak. After long-term use of this composite board, the flame retardant migrates or precipitates, resulting in a decline in the flame retardant performance of the board; the existing glass fiber roving is only treated with a coupling agent, and the fiber and resin rely on a single chemical bond, so the interfacial binding force between the fiber and resin is weak and the mechanical bearing capacity is low.

[0006] To achieve the above object, the technical solution of the present invention is realized as follows: The present invention provides a phenolic resin-based composite material for subway tunnel evacuation platforms, which comprises the following raw materials in parts by weight: 35-40 parts of glass fiber roving, 5-10 parts of modified phenolic resin, 0.4-0.7 parts of curing agent, 0.4-0.7 parts of accelerator, 0.1-0.3 parts of coupling agent, 0.1-0.3 parts of release agent, 1-1.5 parts of industrial methanol, 0.1-0.3 parts of nano filler, and 0.5-1 part of pure water; Among them, the modified phenolic resin is synthesized through the following steps; S1. Add phenol and organosilicon into a reactor under a nitrogen atmosphere, add a catalyst, and raise the temperature to 70-80°C for stirring reaction for 2-3 h to obtain a first intermediate; S2. Then add NaOH to the first intermediate to adjust the pH of the reaction system to 8-9, add formaldehyde and react at 70-80°C for 1-2 h to obtain a second intermediate; S3. Then add NaOH to the second intermediate to adjust the pH of the reaction system to 9-10, add melamine and ethylenediamine and react for a period of time to obtain the modified phenolic resin.

[0007] The composite material of the present invention does not contain harmful phosphorus elements. The introduction of melamine not only endows the phenolic resin with durable flame retardancy, but also significantly improves the bearing capacity of the phenolic resin-based composite material. Moreover, by grafting silicone, the toughness, weather resistance, heat resistance and moisture resistance of the composite material are improved. In particular, silicone forms a ceramic protective layer during combustion, isolating oxygen and heat, thereby improving the fire resistance. Using ethylenediamine as a crosslinking agent, a three-dimensional network structure of "rigid with flexibility" is finally formed, thus endowing the composite material with better bearing capacity, heat resistance and durable flame retardancy.

[0008] Further, the silicone contains isocyanate groups (-NCO) and trialkoxysilyl groups. The isocyanate groups of the silicone react with the hydroxyl groups of phenol to generate a first intermediate. The second intermediate still has hydroxymethyl groups on the basis of the first intermediate. The hydroxymethyl groups of the second intermediate condense with the amino groups in melamine, and a three-dimensional network structure is formed under the action of the ethylenediamine crosslinking agent. Moreover, the covalent bonds generated by the condensation reaction make the flame retardancy more durable, and can also significantly improve the bearing capacity and heat resistance of the composite material.

[0009] Further, in step S1, the silicone is one or more of 3-isocyanatopropyltriethoxysilane, 3-isocyanatopropyltrimethoxysilane, and 4-isocyanatobutyltriethoxysilane.

[0010] Further, the modified phenolic resin accounts for 15-20% of the total raw materials, and the modified phenolic resin is a thermosetting phenolic resin.

[0011] Further, in step S1, the molar ratio of phenol to silicone is 1:0.05-0.2.

[0012] Further, the molar ratio of phenol to formaldehyde is 1:1.3-1.7.

[0013] Further, the total mass ratio of phenol to melamine and ethylenediamine is 1:0.03-0.09, and the molar ratio of melamine to ethylenediamine is 1:0.4-0.6.

[0014] The proportional relationship in this setting should not only ensure that the second intermediate can react fully, but also avoid the influence of excessive melamine and ethylenediamine on the mechanical properties of the composite material.

[0015] Further, the content of the catalyst accounts for 0.1%-3% of the total mass of phenol and silicone.

[0016] Further, the catalyst is one or more of dibutyltin dilaurate, dibutyltin diacetate, stannous octoate, and dioctyltin dilaurate.

[0017] Further, the coupling agent is one or more of silane coupling agent KH550, silane coupling agent KH560, and silane coupling agent KH570.

[0018] Further, the curing agent is one or more of phenolic resin curing agent SGH01, phenolic resin curing agent 213-3, and phenolic resin curing agent PF7301.

[0019] Further, the accelerator is triethanolamine.

[0020] Further, the mold release agent is one or more of calcium stearate, zinc stearate, lithium stearate, stearic acid, stearamide, and ethylene bisstearamide.

[0021] Further, the nano filler is nano silica, and the nano particle size is 10 - 30 nm.

[0022] The nano filler in the present invention can not only enhance the mechanical properties of the composite material, but also, due to the rough structure of the glass fiber roving after pretreatment, the nano filler is filled therein, which can reduce defects and improve the compactness of the overall structure, thereby enhancing the bearing capacity. The nano filler and the modified phenolic resin cooperate to further improve the bearing capacity, flame retardancy, and heat resistance of the composite material.

[0023] Further, in order to ensure the dispersibility of the nano filler, the ultrasonic dispersion method in the prior art can be used to make the dispersion more uniform.

[0024] Further, when preparing the composite material, the glass fiber roving needs to be pretreated first and then blended with other raw materials. The specific steps of the pretreatment are as follows: Step 1: Immerse the glass fiber roving in an aqueous hydrochloric acid solution and soak it at 30°C - 40°C for 10 - 20 minutes. After soaking, rinse it thoroughly with water and dry it. Step 2: Immerse the glass fiber roving dried in Step 1 in a sodium hydroxide solution and soak it at 60°C - 70°C for 10 - 20 minutes. After soaking, rinse it thoroughly with water and dry it to obtain the glass fiber with a roughened surface. Step 3: Immerse the glass fiber with a roughened surface in Step 2 in a coupling agent solution for 20 - 30 minutes to obtain the pretreated glass fiber roving.

[0025] In this setting, the E-glass roving is first treated with hydrochloric acid to remove surface impurities, and then etched with an alkali treatment to roughen the fiber surface while maintaining the fiber strength. The roughness of the fiber surface increases the fiber surface activity. After being modified with a silane coupling agent, the compatibility between the E-glass roving and the phenolic resin matrix is improved, thereby better exerting the mechanical property enhancement effect of the E-glass roving on the phenolic resin.

[0026] Further, the concentration of the hydrochloric acid is 0.5 mol / L to 1 mol / L, and the mass ratio of the E-glass roving to the hydrochloric acid aqueous solution is 1:10 to 15.

[0027] Further, the concentration of the sodium hydroxide is 3 mol / L to 6 mol / L, and the mass ratio of the E-glass roving to the sodium hydroxide solution is 1:10 to 15.

[0028] Further, the coupling agent solution is a silane coupling agent KH570 solution with a mass percentage concentration of 1% - 2%. The solvent of the silane coupling agent KH570 solution is water.

[0029] Further, in step three, the mass ratio of the E-glass roving to the coupling agent solution is 1:10 to 20.

[0030] Compared with the prior art, the phenolic resin-based composite material for subway tunnel evacuation platforms of the present invention has the following advantages: 1) The composite material of the present invention does not contain harmful phosphorus elements. Melamine is introduced to combine with the phenolic resin in a covalent bond manner, thereby endowing the phenolic resin with persistent flame retardancy, significantly improving the bearing capacity of the phenolic resin-based composite material, and improving the toughness, weather resistance, heat resistance, and moisture resistance of the composite material by grafting silicone. In particular, silicone forms a ceramic layer during combustion, isolating oxygen and heat, thereby improving fire resistance. Using ethylenediamine as a crosslinking agent, a "rigid with flexibility" three-dimensional network structure is finally formed, thereby endowing the composite material with good bearing capacity, heat resistance, and persistent flame retardancy. 2) In the present invention, the E-glass roving is first treated with hydrochloric acid to remove surface impurities, and then etched with an alkali treatment to roughen the glass fiber surface while maintaining the fiber strength. The increase in the roughness of the fiber surface exposes more hydroxyl groups, increasing the fiber surface activity. After being modified with a silane coupling agent, the compatibility between the E-glass roving and the phenolic resin matrix is improved, thereby better exerting the mechanical property enhancement effect of the E-glass roving on the phenolic resin. Specific Embodiments

[0031] To make the above objects, features, and advantages of the present invention more obvious and understandable, the following provides a detailed description of specific embodiments of the present invention. The glass fiber roving mentioned in the embodiments is from Hebei Gujia Technology Co., Ltd., and the softening point of the glass fiber roving is 860 °C. Example 1

[0032] Preparation of Modified Phenolic Resin S1. Add 47.5 g of phenol and 7.4 g of 3-isocyanatopropyltriethoxysilane into a reaction kettle under a nitrogen atmosphere, add 0.5 g of dibutyltin dilaurate catalyst, heat up to 70 °C and stir for 3 h to obtain the first intermediate. The synthesis process of this reaction is as follows: .

[0033] This step grafts silicone to improve the long-term thermal stability of phenolic resin and form a protective layer, which forms a ceramic layer during combustion to isolate oxygen and heat, thereby improving fire resistance. Moreover, silicone toughens the material. Through ethylenediamine as a cross-linking agent, a three-dimensional network structure of "steel with flexibility" is finally formed, thereby endowing the composite material with better bearing capacity, heat resistance, and long-term flame retardancy.

[0034] S2. Then add NaOH to the first intermediate to adjust the pH of the reaction system to 8, add 22.3 g of formaldehyde and react at 75 °C for 2 h to obtain the second intermediate; the synthesis process of this reaction is as follows: .

[0035] S3. Then add NaOH to the second intermediate to adjust the pH of the reaction system to 9, add 1.53 g of melamine and 0.36 g of ethylenediamine, heat up to 80 °C, and react for 2 h to obtain the modified phenolic resin.

[0036] Melamine in this step can improve the bearing capacity of the material. The groups in melamine contain nitrogen groups, endowing the phenolic resin with excellent flame retardant properties. Moreover, the amino group in melamine condenses with the hydroxyl group of the second intermediate, making the phenolic resin itself have good flame retardant characteristics. Compared with the hydrogen bond combination of the flame retardant and phenolic resin, the chemical bond combination of the present invention can significantly overcome the defects of easy exudation or migration of the flame retardant, thereby enhancing the persistence of the flame retardant effect and improving the performance of the flame retardant active ingredient. Ethylenediamine as a cross-linking agent, its amino group reacts with hydroxymethyl and silane groups (hydrolyzed Si-OH) to form Si-O-N and C-N-C cross-linking structures, and finally form a three-dimensional network structure, thereby endowing the composite material with better bearing capacity, heat resistance, and long-term flame retardancy. Example 2

[0037] Preparation of Modified Phenolic Resin S1. Add 80.3 g of phenol and 31 g of 3-isocyanatopropyltriethoxysilane into a reaction kettle under a nitrogen atmosphere, add 1.1 g of dibutyltin dilaurate catalyst, heat up to 70 °C and stir for reaction for 3 h to obtain the first intermediate.

[0038] S2. Then add NaOH to the first intermediate to adjust the pH of the reaction system to 9, add 36 g of formaldehyde and react at 75 °C for 2 h to obtain the second intermediate; S3. Then add NaOH to the second intermediate to adjust the pH of the reaction system to 10, add 4.69 g of melamine and 1.1 g of ethylenediamine, heat up to 90 °C and react for 2 h to obtain the modified phenolic resin. Example 3

[0039] Preparation of Modified Phenolic Resin S1. Add 60.2 g of phenol and 11.1 g of 3-isocyanatopropyltriethoxysilane into a reaction kettle under a nitrogen atmosphere, add 0.45 g of dibutyltin dilaurate catalyst, heat up to 70 °C and stir for reaction for 3 h to obtain the first intermediate.

[0040] S2. Then add NaOH to the first intermediate to adjust the pH of the reaction system to 8, add 31 g of formaldehyde and react at 75 °C for 2 h to obtain the second intermediate; S3. Then add NaOH to the second intermediate to adjust the pH of the reaction system to 9, add 2.3 g of melamine and 0.5 g of ethylenediamine, heat up to 85 °C and react for 2 h to obtain the modified phenolic resin. Example 4

[0041] Pretreatment Process of Glass Fiber Rovings Step 1. Immerse the glass fiber rovings into a 0.6 mol / L hydrochloric acid aqueous solution and soak at 35 °C for 15 minutes. After soaking, rinse thoroughly with water and dry; the mass ratio of the glass fiber rovings to the hydrochloric acid aqueous solution is 1:15.

[0042] Step 2. Immerse the glass fiber rovings dried in Step 1 into a sodium hydroxide solution and soak at 65 °C for 15 minutes. After soaking, rinse thoroughly with water and dry to obtain the surface-roughened glass fiber; the mass ratio of the glass fiber rovings to the sodium hydroxide aqueous solution is 1:12.

[0043] Step 3. Immerse the surface-roughened glass fiber in Step 2 into a 1% mass concentration solution of silane coupling agent KH570 for 30 min and dry to obtain the pretreated glass fiber rovings. The mass ratio of the glass fiber rovings to the coupling agent solution is 1:20. Example 5

[0044] Pretreatment Process of E-Glass Rovings Step 1: Immerse the E-glass rovings in a 0.5 mol / L hydrochloric acid aqueous solution at 40 °C for 20 minutes. After immersion, rinse thoroughly with water and dry. The mass ratio of the E-glass rovings to the hydrochloric acid aqueous solution is 1:10.

[0045] Step 2: Immerse the dried E-glass rovings from Step 1 in a sodium hydroxide solution at 60 °C for 20 minutes. After immersion, rinse thoroughly with water and dry to obtain surface-roughened E-glass. The mass ratio of the E-glass rovings to the sodium hydroxide aqueous solution is 1:12.

[0046] Step 3: Immerse the surface-roughened E-glass from Step 2 in a 1.5% by mass silane coupling agent KH570 solution for 30 min and dry to obtain the pretreated E-glass rovings. The mass ratio of the E-glass rovings to the coupling agent solution is 1:15. Example 6

[0047] Pretreatment Process of E-Glass Rovings Step 1: Immerse the E-glass rovings in a 0.6 mol / L hydrochloric acid aqueous solution at 35 °C for 15 minutes. After immersion, rinse thoroughly with water and dry. The mass ratio of the E-glass rovings to the hydrochloric acid aqueous solution is 1:10.

[0048] Step 2: Immerse the dried E-glass rovings from Step 1 in a sodium hydroxide solution at 65 °C for 15 minutes. After immersion, rinse thoroughly with water and dry to obtain surface-roughened E-glass. The mass ratio of the E-glass rovings to the sodium hydroxide aqueous solution is 1:12.

[0049] Step 3: Immerse the surface-roughened E-glass from Step 2 in a 2% by mass silane coupling agent KH570 solution for 30 min and dry to obtain the pretreated E-glass rovings. The mass ratio of the E-glass rovings to the coupling agent solution is 1:10. Example 7

[0050] A phenolic resin-based composite material for subway tunnel evacuation platforms comprises the following raw materials in parts by weight: 40 parts of untreated E-glass rovings, 10 parts of the modified phenolic resin of Example 3, 0.4 part of phenolic resin curing agent (213-3), 0.4 part of triethanolamine, 0.2 part of silane coupling agent (KH550), 0.2 part of calcium stearate release agent, 1 part of industrial methanol, 0.2 part of nano-silica (particle size 30 nm), and 1 part of pure water.

[0051] After mixing the above raw materials, use conventional equipment and processes for pultrusion molding into plates. Example 8

[0052] The difference between this example and Example 7 is that 40 parts of untreated E-glass roving are replaced by the pretreated E-glass roving in Example 4. Example 9

[0053] A phenolic resin-based composite material for subway tunnel evacuation platforms comprises the following raw materials in parts by weight: 37 parts of pretreated E-glass roving according to Example 4, 8 parts of the modified phenolic resin in Example 3, 0.5 part of phenolic resin curing agent (213-3), 0.6 part of triethanolamine, 0.1 part of silane coupling agent (KH550), 0.1 part of calcium stearate release agent, 1.5 parts of industrial methanol, 0.1 part of nano-silica (particle size 30 nm), and 1 part of pure water.

[0054] After mixing the above raw materials, pultrusion molding is carried out into plates by using conventional equipment and processes.

[0055] Comparative Example 1 The difference between this comparative example and Example 8 is that the preparation steps of the modified phenolic resin are as follows: in a reaction kettle under a nitrogen atmosphere, 60.2 g of phenol is added, NaOH is added to adjust the pH of the reaction system to 8, 31 g of formaldehyde is added and reacted at 75 °C for 2 h; then NaOH is added to adjust the pH of the reaction system to 9, 2.3 g of melamine and 0.5 g of ethylenediamine are added and the temperature is raised to 85 °C, and the reaction is carried out for 2 h to obtain the modified phenolic resin.

[0056] Comparative Example 2 The difference between this comparative example and Example 8 is that melamine is not added in step S3.

[0057] Comparative Example 3 The difference between this comparative example and Example 8 is that ethylenediamine is not added in step S3.

[0058] Comparative Example 4 The difference between this comparative example and Example 8 is that during the pretreatment, the E-glass roving is not treated with hydrochloric acid solution and sodium hydroxide solution. The pretreatment is to soak the E-glass roving in a 4% coupling agent KH570 solution for 30 min and dry it to obtain the pretreated E-glass roving, and the mass ratio of the E-glass roving to the coupling agent solution is 1:10.

[0059] Comparative Example 5 The difference between this comparative example and Example 8 is that nano-silica is replaced by iron oxide.

[0060] For the composite plates obtained in Examples 7-9 and Comparative Examples 1-5, the following performance tests are carried out: 1) The compression strength is tested according to GB / T1448-2005; the impact strength is tested according to GB / T 1451-2005; the bending strength is tested according to GB / T1449-2005; 2) The oxygen index is measured in accordance with GB / T 2406.2-2009; 3) Fire resistance test: According to GB50016-2006 "Code for Fire Protection Design of Buildings": The measured performance parameters are shown in Table 1 below: Table 1 Test results of load-bearing capacity, fire resistance and flame retardancy of different composite materials

[0061] In the phenolic resin-based composite material formulations in Examples 8 to 9 of the present invention, pretreated glass fiber roving and modified phenolic resin are used, and other components are within the preferred range, so that the composite material has excellent bearing capacity (bending strength, impact strength, compressive strength), fire resistance, and flame retardancy.

[0062] Embodiment 7 of the present invention is unpretreated glass fiber roving. Because the surface of the glass fiber itself is smooth and inert, it only relies on physical adsorption (van der Waals force) when not treated and cannot form a strong chemical bond with the phenolic resin. The interface bonding is poor and the stress transfer efficiency is low, resulting in low bearing capacity. In addition, the poor interface bonding will make the fiber easily pyrolyzed and ineffective at high temperature, forming stratification, accelerating the oxidative degradation of the material, and the interface defects promote flame propagation, resulting in reduced flame retardant properties.

[0063] By comparing Example 7 and Comparative Example 4, it can be seen that the glass fiber roving treated with a slightly higher concentration of KH550 has a slightly lower corresponding performance of the composite material than the glass fiber roving without any treatment. This is because the coupling agent molecules are excessively accumulated to form a weak interface layer, which reduces the interface strength and causes the bearing capacity of the composite material to decrease. Excessive coupling agent forms an organic interface layer with poor thermal stability, which accelerates thermal degradation and causes a decrease in fire resistance. In addition, excessive coupling agent decomposes at high temperature to generate combustible gas, which weakens the carbonization barrier effect of the phenolic resin and also causes a decrease in flame retardant properties.

[0064] In summary, in the composite material of the present invention, the ingredients and contents in the formula, the pretreatment process of the glass fiber roving and the corresponding reagent content, the modified phenolic resin molding process and the reagent content, etc. are all optimized and play a synergistic role with each other, ultimately making the composite material prepared by the present invention have excellent bearing capacity (bending strength, impact strength, compressive strength), fire resistance, heat resistance, and flame retardancy.

[0065] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims

1. A phenolic resin-based composite material for a subway tunnel evacuation platform, characterized in that: The invention comprises the following raw materials in parts by weight: 35-40 parts of glass fiber roving, 5-10 parts of modified phenolic resin, 0.4-0.7 parts of curing agent, 0.4-0.7 parts of accelerator, 0.1-0.3 parts of coupling agent, 0.1-0.3 parts of release agent, 1-1.5 parts of industrial methanol, 0.1-0.3 parts of nano filler and 0.5-1 parts of pure water; Wherein, the modified phenolic resin is synthesized by the following steps; S1, adding phenol and organosilicon into a reactor in a nitrogen atmosphere, adding a catalyst, heating to 70-80°C and stirring for reaction for 2-3 hours to obtain a first intermediate; S2, then add NaOH to the first intermediate to adjust the pH of the reaction system to 8-9, add formaldehyde and react at 70-80°C for 1-2 h to obtain a second intermediate; S3. Then, NaOH is added to the second intermediate to adjust the pH of the reaction system to 9-10, and melamine and ethylenediamine are added. The temperature is raised to 80-90° C. and the reaction is carried out for 2-3 hours to obtain a modified phenolic resin.

2. The composite material according to claim 1, characterized in that In step S1, the organic silicon is one or more of 3-isocyanatepropyltriethoxysilane, 3-isocyanatepropyltrimethoxysilane, and 4-isocyanatebutyltriethoxysilane.

3. The composite material according to claim 1, characterized in that In step S1, the molar ratio of phenol to organosilicon is 1:0.05-0.

2.

4. The composite material according to claim 1, characterized in that The molar ratio of phenol to formaldehyde is 1:1.3-1.

7.

5. The composite material according to claim 1, characterized in that The total mass ratio of the phenol to melamine and ethylenediamine is 1:0.03-0.09, wherein the molar ratio of melamine to ethylenediamine is 1:0.4-0.

6.

6. The composite material according to claim 1, characterized in that The coupling agent is one or more of silane coupling agent KH550, silane coupling agent KH560, and silane coupling agent KH570.

7. The composite material according to claim 1, characterized in that The curing agent is one or more of phenolic resin curing agent SGH01, phenolic resin curing agent 213-3, and phenolic resin curing agent PF7301.

8. The composite material according to claim 1, characterized in that The accelerator is triethanolamine.

9. The composite material according to claim 1, characterized in that The release agent is one or more of calcium stearate, zinc stearate, lithium stearate, stearic acid, stearic acid amide, and ethylene bis stearic acid amide.

10. The composite material according to claim 1, characterized in that The nano filler is nano silicon dioxide.

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