Heat prevention and insulation composite material as well as preparation method and application thereof

Abstract

The invention discloses a heat-proof and heat-insulation composite material and a preparation method and application thereof, relates to the field of phenolic resin-based composite materials, and firstly provides a modified phenolic resin composition for the heat-proof and heat-insulation composite material, which comprises phenolic resin, a curing agent, a phenolic aldehyde modifier, a coupling agent and an organic solvent; and then impregnating fiber cloth with the modified phenolic resin composition to obtain a prepreg, laying the prepreg, and carrying out gradient heating hot-pressing curing treatment to obtain the heat-proof and heat-insulation composite material. The composite material has relatively low density, has mechanical properties, large heat flow ablation resistance and reusable performance, is suitable for being applied to a thermal protection system, and is particularly applied to thermal protection of the bottom of an outsole of a return type carrier rocket.

Description

Technical Field

[0001] The invention relates to the field of phenolic resin-based composite materials, in particular to a heat-insulating composite material and a preparation method and application thereof. Background Art

[0002] In modern science and technology and industrial fields, the performance requirements for materials are becoming increasingly higher, especially in some specific application scenarios, such as aerospace and other fields. When a spacecraft enters the atmosphere, its surface will be subjected to extremely high temperatures and heat flows. This requires a material with anti-thermal insulation properties that can effectively block heat flow transfer and protect the internal structure and equipment of the spacecraft.

[0003] In traditional spacecraft, phenolic resin-based composite materials are usually used as ablative materials. When subjected to high temperatures, ablative materials will undergo an ablation reaction to form a heat-insulating carbonized layer to protect the internal structure of the spacecraft. With the improvement of scientific and technological levels and the increasing demand for space exploration, the development of the aerospace field is facing new opportunities and challenges. The cost of using disposable launch vehicles is extremely high, while reusable launch vehicles are a key means to reduce space transportation costs and an effective way to improve space rapid response capabilities. The ultimate goal is to recycle expensive rocket bodies, engines and electrical equipment, representing the highest level of aerospace technology today.

[0004] The bottom structure of the tail of the rocket body and the side wall structure of the tail cabin are the key parts of the heat protection of the rocket during flight. If specific materials are not used for heat protection, the structural metal materials will completely lose their bearing capacity in the thermal vibration environment, which will not only make them unrecoverable, but also lead to catastrophic consequences. The current launch vehicles use glass fiber / phenolic resin (FRP) laminates as hard structures (heat protection panels) at most, while the scouring heat flow at the bottom of the new reusable return launch vehicle is an order of magnitude higher than that of the current rockets. The heat protection performance of the current ablation-resistant materials cannot meet the use requirements, such as the back temperature not exceeding 100°C, the thickness of the unablated carbonization exceeding 3mm, and the lightweight and high-strength mechanical properties. It is urgent to develop new ablation-resistant and heat-insulating composite materials to solve the problem that the heat protection capacity of the ablation-resistant materials at the bottom of the current launch vehicles does not meet the heat protection requirements of the new reusable rockets. Summary of the invention

[0005] In view of this, an object of the present invention is to provide a heat-insulating composite material and a preparation method and application thereof.

[0006] The objective of the present invention is achieved through the following technical solutions: <First aspect> The present invention provides a method for preparing a heat-insulating composite material, comprising the following steps: S1, uniformly impregnating the modified phenolic resin composition into the fiber cloth, removing the solvent to obtain a prepreg, wherein the modified phenolic resin composition is a mixture of a liquid phenolic resin, a curing agent, a phenolic modifier, a coupling agent and an organic solvent; S2, stacking the prepregs in layers, subjecting them to hot pressing and curing treatment, and then cooling and releasing the pressure to obtain the heat-insulating composite material.

[0007] As an embodiment, the mass ratio of the modified phenolic resin composition to the fiber cloth is (170 ~ 200): (80 ~ 100).

[0008] As an embodiment, the modified phenolic resin composition is uniformly impregnated into the fiber cloth by a flow injection impregnation method.

[0009] As an embodiment, the parameters of the flow injection impregnation method are: pressure 1-2 MPa, temperature 20-30° C., and flow rate 15-25 mL / min.

[0010] In some embodiments, the parameters of the flow injection impregnation method are: pressure 1 MPa, temperature 25° C., and flow rate 20 mL / min.

[0011] As an embodiment, the fiber cloth does not contain inorganic fillers.

[0012] As an embodiment, the fiber cloth includes a fiber cloth woven from one or more of high silica fiber, quartz fiber, and glass fiber.

[0013] As an embodiment, the fiber cloth is high-silica fiber cloth.

[0014] As an embodiment, the thickness of the high silica fiber cloth is 0.24-0.28 mm, and the mass per unit area is 230-250 g / m 2 .

[0015] In some embodiments, the single layer thickness of the high silica fiber cloth is 0.26 mm, and the mass per unit area is 240 g / m 2 .

[0016] As an embodiment, the prepreg is alternately laid in 0° / 90° manner.

[0017] As an embodiment, the hot pressing curing process is performed by heating in a gradient heating manner.

[0018] As an embodiment, the parameters of the hot pressing curing treatment are: pressure of 2-6 MPa, gradient temperature increase to 140-170°C, and heat preservation for 4-8 hours.

[0019] In some embodiments, during the hot pressing curing process, the pressure is 5 MPa.

[0020] As an implementation scheme, the gradient heating method is: first heating to 60-100°C and keeping warm for 2-6 hours, then heating to 110-130°C and keeping warm for 2-6 hours, and then heating to 140-170°C and keeping warm for 4-8 hours.

[0021] As an implementation scheme, the gradient heating method is: first heating to 60-100°C and keeping warm for 4-5 hours, then heating to 110-130°C and keeping warm for 4-5 hours, and then heating to 140-170°C and keeping warm for 4-6 hours.

[0022] In some embodiments, the gradient temperature increase is as follows: first increase the temperature to 60°C and keep it for 5 hours, then increase the temperature to 110°C and keep it for 5 hours, and then increase the temperature to 140°C and keep it for 5 hours.

[0023] As an implementation scheme, the cooling in S2 is carried out by furnace cooling.

[0024] As an embodiment, the pressure release in S2 is performed after the temperature drops below 70°C.

[0025] In some embodiments, the pressure relief is performed after the temperature is reduced to 60° C. in S2.

[0026] As an embodiment, the removal of the solvent in S1 is carried out by air drying.

[0027] In some embodiments, the removal of the solvent in S1 is carried out by drying at room temperature, and the drying time is 24 to 48 hours.

[0028] <Second Aspect> The present invention provides a modified phenolic resin composition for heat-insulating composite materials, which comprises the following components in parts by mass: Liquid phenolic resin: 80~100 parts; Curing agent: 10~20 parts; Phenolic modifier: 1~20 parts; Coupling agent: 1~10 parts; Organic solvent: 50~80 parts.

[0029] As an embodiment, the liquid phenolic resin is liquid boron-modified phenolic resin.

[0030] As an embodiment, the curing agent is selected from one or more of hexamethylenetetramine, triethylenetetramine, and 4,4-diphenylsulfonediamine.

[0031] In some embodiments, the curing agent is hexamethylenetetramine.

[0032] As an embodiment, the phenolic modifier is selected from one or more of methyltrimethoxysilane, dimethyldimethoxysilane, and dimethyldiethoxysilane.

[0033] In some embodiments, the phenolic modifier is methyltrimethoxysilane.

[0034] As an embodiment, the coupling agent is selected from one or more of KH550 coupling agent, KH560 coupling agent, and KH570 coupling agent.

[0035] In some embodiments, the coupling agent is KH550 coupling agent.

[0036] As an embodiment, the organic solvent is selected from anhydrous ethanol and / or acetic acid.

[0037] In some embodiments, the organic solvent is anhydrous ethanol.

[0038] In some embodiments, the organic solvent is acetic acid.

[0039] As an embodiment, the modified phenolic resin composition is mixed uniformly by stirring.

[0040] As an embodiment, the stirring parameter of the modified phenolic resin composition is 200-400 r / min.

[0041] In some embodiments, the stirring parameter of the modified phenolic resin composition is 300 r / min.

[0042] As an embodiment, the modified phenolic resin composition is mixed uniformly at 20-80°C.

[0043] In some embodiments, the modified phenolic resin composition is mixed at 20°C.

[0044] As an embodiment, the modified phenolic resin composition is calculated by weight: Liquid phenolic resin: 80~100 parts; Hexamethylenetetramine: 10-20 parts; Methyltrimethoxysilane: 1-20 parts; KH550: 1~10 servings; Anhydrous ethanol: 50~80 parts.

[0045] In some embodiments, the modified phenolic resin composition is calculated by weight: Liquid phenolic resin: 80~100 parts; Hexamethylenetetramine: 10 parts; Methyltrimethoxysilane: 2-10 parts; KH550: 1~10 servings; Anhydrous ethanol: 60~80 parts.

[0046] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a modified phenolic resin composition for heat-insulating composite materials. Firstly, the resin matrix in the composition is a liquid boron-modified phenolic resin. Compared with a powdered phenolic resin matrix, the resin matrix has better bonding performance with fibers, and the overall performance of the prepared heat-insulating composite material is better. Secondly, organic silane is used as a phenolic modifier in the composition to further improve the heat resistance and ablation resistance of the phenolic resin, thereby obtaining a modified phenolic resin with a cross-linked network, which has good thermal stability at high temperatures. Thirdly, inorganic fillers are not used in the present invention, but silane is used to introduce silicon elements to improve the ablation performance. At the same time, silane can be better mixed with the phenolic resin and dispersed evenly, and is low in price, which is better than inorganic fillers.

[0047] The present invention provides a method for preparing a heat-insulating composite material, wherein a fiber braid is obtained by weaving a high-strength fiber material, and a modified phenolic resin is impregnated on the surface of the fiber braid to improve the interface bonding performance between the resin and the fiber. The preparation is carried out through a gradient temperature rising curing step. The prepared heat-insulating composite material has good mechanical properties and excellent ablation resistance, which effectively solves the problem that the currently used heat-insulating materials cannot withstand large heat flow ablation and multiple ablation.

[0048] The present invention provides an application of the above-mentioned heat-insulating composite material, which is applied to thermal protection of spacecraft, engine components, etc. in the field of aerospace, and is particularly suitable for application to thermal protection of the bottom of a returnable launch vehicle. DETAILED DESCRIPTION

[0049] The present invention is described in detail below in conjunction with embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, some adjustments and improvements can also be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0050] This specific embodiment provides a heat-insulating composite material, a preparation method thereof, uses thereof, and a pre-preg liquid composition used in the preparation method.

[0051] A method for preparing a heat-insulating composite material comprises the following steps: S1. Prepare pre-soak Mixing phenolic resin, curing agent, phenolic modifier, coupling agent and organic solvent, stirring evenly to obtain modified phenolic resin solution (hereinafter referred to as pre-preg solution); S2, impregnation of fiber cloth and curing and cross-linking S21, impregnating the fiber cloth: impregnating the prepreg liquid evenly into the fiber cloth, drying it, removing most of the solvent, and obtaining a prepreg; S22. Curing and cross-linking: After the prepreg is laid to a certain thickness, it is cured by a hot pressing curing process, and the pressure is released after cooling in the furnace. The mold is removed to obtain a reusable anti-insulation composite material that is resistant to large heat flux ablation.

[0052] The preparation method of the above-mentioned heat-insulating composite material is specifically introduced below through three embodiments.

[0053] Example 1 In S1, the formula of the pre-dip composition is: The phenolic resin is liquid boron-modified phenolic resin, and the amount is 100 parts (parts by mass, the following amounts are all expressed as parts by mass unless otherwise specified); The curing agent is hexamethylenetetramine, and the dosage is 10 parts; The phenolic modifier is methyltrimethoxysilane, and the dosage is 10 parts; The coupling agent used was KH550 coupling agent, and the dosage was 5 parts; The organic solvent is anhydrous ethanol, and the usage amount is 60 parts.

[0054] In this embodiment, in S1, the parameters for uniform stirring are: stirring at 20°C and 300 rpm for 20 min.

[0055] In S2, the prepreg is evenly impregnated into the fiber cloth, the impregnated fiber cloth is dried, and most of the solvent is removed to obtain a prepreg. The impregnation method is: flow injection impregnation process, using an RTM injection machine, a pressure of 1 MPa, a temperature of 25°C, and a flow rate of 20 mL / min. After the prepreg is evenly impregnated into the fiber cloth, the solvent is removed by room temperature drying, and the drying time is 24 h.

[0056] In this embodiment, the fiber cloth is selected with a unit area mass of 240 g / m 2 , high silica fiber cloth with a thickness of 0.26 mm, the dosage is 80 parts.

[0057] In this embodiment, most of the solvent is removed by drying at room temperature.

[0058] In S2, the prepreg is alternately laid in a 0° / 90° manner to obtain an impregnated fiber cloth layer.

[0059] In S2, the hot pressing curing process is as follows: under a pressure of 5 MPa, first heat the temperature to 60 °C at a heating rate of 5 °C / min, keep it at 60 °C for 5 h, then heat the temperature to 110 °C at a heating rate of 5 °C / min, keep it at 110 °C for 5 h, then heat the temperature to 140 °C at a heating rate of 5 °C / min, keep it at 140 °C for 5 h, and finally, after the curing is completed, slowly cool it to 60 °C in the furnace, release the pressure, and demold to obtain a thermal insulation composite material with a thickness of 15 mm.

[0060] Example 2 In S1, the formulas of the compositions in the pre-soak are: The phenolic resin is liquid boron-modified phenolic resin, and the dosage is 100 parts; The curing agent is hexamethylenetetramine, and the dosage is 10 parts; The phenolic modifier is methyltrimethoxysilane, with a dosage of 2 parts; The coupling agent used is KH550 coupling agent, and the dosage is 1 part; The organic solvent is anhydrous ethanol, and the usage amount is 80 parts.

[0061] In this embodiment, in S1, the parameters for uniform stirring are: stirring at 20°C and 300 rpm for 20 min.

[0062] In S2, the prepreg is evenly impregnated into the fiber cloth, the impregnated fiber cloth is dried, and most of the solvent is removed to obtain a prepreg. The impregnation method is: flow injection impregnation process, using an RTM injection machine, a pressure of 1 MPa, a temperature of 25°C, and a flow rate of 20 mL / min. After the prepreg is evenly impregnated into the fiber cloth, the solvent is removed by room temperature drying, and the drying time is 24 h.

[0063] In this embodiment, the fiber cloth is selected with a unit area mass of 240 g / m 2 , high silica fiber cloth with a thickness of 0.26 mm, the usage is 100 parts.

[0064] In this embodiment, most of the solvent is removed by drying at room temperature.

[0065] In S2, the prepreg is alternately laid in a 0° / 90° manner to obtain an impregnated fiber cloth layer.

[0066] In S2, the hot pressing curing process is as follows: under a pressure of 5 MPa, first heat the temperature to 60 °C at a heating rate of 5 °C / min, keep it at 60 °C for 5 h, then heat the temperature to 110 °C at a heating rate of 5 °C / min, keep it at 110 °C for 5 h, then heat the temperature to 140 °C at a heating rate of 5 °C / min, keep it at 140 °C for 5 h, and finally, after the curing is completed, slowly cool it to 60 °C in the furnace, release the pressure, and demold to obtain a thermal insulation composite material with a thickness of 15 mm.

[0067] Example 3 In S1, the formulas of the compositions in the pre-soak are: The phenolic resin is a liquid boron-modified phenolic resin, and the dosage is 80 parts; The curing agent is hexamethylenetetramine, and the dosage is 10 parts; The phenolic modifier is methyltrimethoxysilane, with a dosage of 5 parts; The coupling agent used was KH550 coupling agent, and the dosage was 10 parts; The organic solvent is anhydrous ethanol, and the usage amount is 70 parts.

[0068] In this embodiment, in S1, the parameters for uniform stirring are: stirring at 20°C and 300 rpm for 20 min.

[0069] In S2, the prepreg is evenly impregnated in the high silica fiber, the impregnated fiber cloth is dried, and most of the solvent is removed to obtain the prepreg. The impregnation method is: flow injection impregnation process, using an RTM injection machine, a pressure of 1 MPa, a temperature of 25°C, and a flow rate of 20 mL / min. After the prepreg is evenly impregnated in the fiber cloth, the solvent is removed by room temperature drying, and the drying time is 24 h.

[0070] In this embodiment, the fiber cloth is selected with a unit area mass of 240 g / m 2 , high silica fiber cloth with a thickness of 0.26 mm, the usage is 100 parts.

[0071] In this embodiment, most of the solvent is removed by drying at room temperature.

[0072] In S2, the prepreg is alternately laid in a 0° / 90° manner to obtain an impregnated fiber cloth layer.

[0073] In S2, the hot pressing curing process is as follows: under a pressure of 5 MPa, first heat the temperature to 60 °C at a heating rate of 5 °C / min, keep it at 60 °C for 5 h, then heat the temperature to 110 °C at a heating rate of 5 °C / min, keep it at 110 °C for 5 h, then heat the temperature to 140 °C at a heating rate of 5 °C / min, keep it at 140 °C for 5 h, and finally, after the curing is completed, slowly cool it to 60 °C in the furnace, release the pressure, and demold to obtain a thermal insulation composite material with a thickness of 15 mm.

[0074] Example 4 In S1, the formula of the pre-dip composition is: The phenolic resin is liquid boron-modified phenolic resin, and the dosage is 100 parts; The curing agent is hexamethylenetetramine, and the dosage is 10 parts; The phenolic modifier is methyltrimethoxysilane, and the dosage is 10 parts; The coupling agent used was KH550 coupling agent, and the dosage was 5 parts; Acetic acid was selected as the organic solvent in an amount of 60 parts.

[0075] In this embodiment, in S1, the parameters for uniform stirring are: stirring at 20°C and 300 rpm for 20 min.

[0076] In S2, the prepreg is evenly impregnated into the fiber cloth, the impregnated fiber cloth is dried, and most of the solvent is removed to obtain a prepreg. The impregnation method is: flow injection impregnation process, using an RTM injection machine, a pressure of 1 MPa, a temperature of 25 °C, and a flow rate of 20 mL / min. After the prepreg is evenly impregnated into the fiber cloth, the solvent is removed by room temperature drying, and the drying time is 48 h.

[0077] In this embodiment, the fiber cloth is selected with a unit area mass of 240 g / m 2 , high silica fiber cloth with a thickness of 0.26 mm, the dosage is 80 parts.

[0078] In this embodiment, most of the solvent is removed by drying at room temperature.

[0079] In S2, the prepreg is alternately laid in a 0° / 90° manner to obtain an impregnated fiber cloth layer.

[0080] In S2, the hot pressing curing process is as follows: under a pressure of 5 MPa, first heat the temperature to 60 °C at a heating rate of 5 °C / min, keep it at 60 °C for 5 h, then heat the temperature to 110 °C at a heating rate of 5 °C / min, keep it at 110 °C for 5 h, then heat the temperature to 140 °C at a heating rate of 5 °C / min, keep it at 140 °C for 5 h, and finally, after the curing is completed, slowly cool it to 60 °C in the furnace, release the pressure, and demold to obtain a thermal insulation composite material with a thickness of 15 mm.

[0081] Example 5 In S1, the formula of the pre-dip composition is: The phenolic resin is a liquid boron-modified phenolic resin, and the dosage is 90 parts; The curing agent is hexamethylenetetramine, and the dosage is 10 parts; The phenolic modifier is methyltrimethoxysilane, with an amount of 20 parts; The coupling agent used was KH550 coupling agent, and the dosage was 5 parts; The organic solvent is anhydrous ethanol, and the usage amount is 60 parts.

[0082] In this embodiment, in S1, the parameters for uniform stirring are: stirring at 20°C and 300 rpm for 20 min.

[0083] In S2, the prepreg is evenly impregnated into the fiber cloth, the impregnated fiber cloth is dried, and most of the solvent is removed to obtain a prepreg. The impregnation method is: flow injection impregnation process, using an RTM injection machine, a pressure of 1 MPa, a temperature of 25 °C, and a flow rate of 20 mL / min. After the prepreg is evenly impregnated into the fiber cloth, the solvent is removed by room temperature drying, and the drying time is 48 h.

[0084] In this embodiment, the fiber cloth is selected with a unit area mass of 240 g / m 2 , high silica fiber cloth with a thickness of 0.26 mm, the dosage is 80 parts.

[0085] In this embodiment, most of the solvent is removed by drying at room temperature.

[0086] In S2, the prepreg is alternately laid in a 0°-90° manner to obtain an impregnated fiber cloth layer.

[0087] In S2, the hot pressing curing process is as follows: under a pressure of 5 MPa, first heat the temperature to 60 °C at a heating rate of 5 °C / min, keep it at 60 °C for 5 h, then heat the temperature to 110 °C at a heating rate of 5 °C / min, keep it at 110 °C for 5 h, then heat the temperature to 140 °C at a heating rate of 5 °C / min, keep it at 140 °C for 5 h, and finally, after the curing is completed, slowly cool it to 60 °C in the furnace, release the pressure, and demold to obtain a thermal insulation composite material with a thickness of 15 mm.

[0088] Detection and analysis The following describes the performance tests of the heat-insulating composite materials prepared in the above-mentioned Examples 1 to 5. The test results are shown in Table 1, wherein the test methods of each performance are as follows: Density: Tested according to GB / T 1463-2005; Tensile strength: tested according to GB / T 1447-2005; Bending strength: tested according to GB / T 1449-2005; Thermal conductivity: Tested according to GB / T 3139-2005; Ablation performance: tested according to GJB 323A-96.

[0089]

[0090] From the data in Table 1, it can be seen that the thermal conductivity of the heat-insulating composite materials prepared in Examples 1 to 5 is 0.082~0.157W / (m·k), the tensile strength is about 170MPa, and the bending strength is about 280MPa; the oxyacetylene ablation test (test condition is 850 kW / m 2 Heat flux ablation 91 s, 2522 kW / m 2 Heat flux ablation 15 s, 850 kW / m 2 Heat flux ablation for 35 s), the back temperature rise is 60~80 ℃, the uncarbonized thickness of the composite material after ablation exceeds 9 mm (composite material thickness 15 mm), and the ablated carbonized layer can block the heat of secondary ablation. In other words, the heat-insulating composite material prepared by the present invention has the advantages of low density, excellent mechanical properties, excellent resistance to large heat flux ablation, and reusability.

[0091] The heat-insulating composite material prepared by the method is suitable for use in thermal protection of spacecraft, engine components, etc. in the aerospace field, and is particularly suitable for use in thermal protection of the bottom of a returnable launch vehicle.

[0092] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is limited by the attached embodiments and their equivalents.

Claims

1. A method for preparing a heat-insulating composite material, characterized in that: The following steps are involved: S1, using a flow injection impregnation method to uniformly impregnate a modified phenolic resin composition into a fiber cloth, and removing the solvent to obtain a prepreg, wherein the modified phenolic resin composition is a mixture of a liquid phenolic resin, a curing agent, a phenolic modifier, a coupling agent and an organic solvent; S2, stacking the prepregs in layers, performing hot pressing and curing treatment, cooling and depressurizing to obtain the heat-insulating composite material, wherein the hot pressing and curing treatment is performed by heating in a gradient heating manner.

2. The method for preparing the heat-insulating composite material according to claim 1, characterized in that: The fiber cloth includes a fiber cloth woven from one or more of high-silica fiber, quartz fiber, and glass fiber, and the mass ratio of the modified phenolic resin composition to the fiber cloth is (170-200): (80-100).

3. The method for preparing the heat-insulating composite material according to claim 1, characterized in that: The parameters of the flow injection impregnation method are: pressure 1-2 MPa, temperature 20-30°C, and flow rate 15-25 mL / min.

4. The method for preparing the heat-insulating composite material according to claim 1, characterized in that: The parameters of the hot pressing curing treatment are: pressure of 2-6 MPa, gradient temperature increase to 140-170°C, and holding time of 4-8 h.

5. The method for preparing the heat-insulating composite material according to claim 1, characterized in that: The temperature reduction in S2 is carried out by furnace cooling, and the pressure relief is carried out after the temperature drops below 70°C.

6. The method for preparing the heat-insulating composite material according to claim 1, characterized in that: The components of the modified phenolic resin composition are as follows by mass: Liquid phenolic resin: 80~100 parts; Curing agent: 10~20 parts; Phenolic modifier: 1~20 parts; Coupling agent: 1~10 parts; Organic solvent: 50~80 parts.

7. The method for preparing the heat-insulating composite material according to claim 6, characterized in that: It also includes one or more of the following technical features: A. The liquid phenolic resin is selected from liquid boron-modified phenolic resin; B. The curing agent is selected from one or more of hexamethylenetetramine, triethylenetetramine, and 4,4-diphenylsulfonediamine; C. The phenolic modifier is selected from one or more of methyltrimethoxysilane, dimethyldimethoxysilane, and dimethyldiethoxysilane; D. The coupling agent is selected from one or more of KH550 coupling agent, KH560 coupling agent, and KH570 coupling agent; E. The organic solvent is selected from anhydrous ethanol and / or acetic acid.

8. The method for preparing the heat-insulating composite material according to claim 6, characterized in that: It also includes one or more of the following technical features: A. uniformly mixing the modified phenolic resin composition by stirring at a stirring speed of 200-400 r / min; B. The modified phenolic resin composition is mixed uniformly at 20-80°C.

9. A heat-insulating composite material, characterized in that: The heat-insulating composite material is prepared according to the preparation method of any one of claims 1 to 8.

10. An application of the heat-insulating composite material according to claim 9, characterized in that: The heat-insulating composite material is used in a heat protection system.

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