阅读说明：本技术 一种隔热材料的制备方法及由该方法制得的隔热材料 (Preparation method of heat insulation material and heat insulation material prepared by same ) 是由 苏力军 宋寒 张丽娟 李健 裴雨辰 于 2019-09-30 设计创作，主要内容包括：本发明涉及一种隔热材料的制备方法及由该方法制得的隔热材料。制备方法包括：(1)抗冲刷纤维基体的制备：将第一纤维布和第一纤维网胎叠加并针刺,形成下纤维预制体；继续叠加第二纤维网胎并针刺,在下纤维预制体上形成中纤维预制体；继续叠加至少一层的第三纤维布和第三纤维网胎并针刺,每层针刺时喷洒包含陶瓷填料和酚醛粘结剂的表面增强材料5-15g/cm<Sup>2</Sup>,形成上纤维预制体；采用纤维将下纤维预制体、中纤维预制体和上纤维预制体缝合,经固化得到所述抗冲刷纤维基体；(2)烧蚀复合材料前驱体的制备；(3)复合。由于整体结构气凝胶材料的存在,烧蚀材料的整体隔热性能优异,由于陶瓷填料存在,烧蚀材料表面具有较高的抗冲刷性能。(The invention relates to a preparation method of a heat insulation material and the heat insulation material prepared by the method. The preparation method comprises the following steps: (1) preparing an anti-scouring fiber matrix: superposing and needling a first fiber cloth and a first fiber net tire to form a lower fiber preform; continuously superposing the second fiber net tire and needling to form a middle fiber preform on the lower fiber preform; continuously superposing at least one layer of third fiber cloth and third fiber net tire and needling, wherein pottery is sprayed during needling of each layerSurface reinforcing material of porcelain filler and phenolic aldehyde binder 5-15g/cm 2 Forming an upper fiber preform; sewing the lower fiber preform, the middle fiber preform and the upper fiber preform by using fibers, and curing to obtain the scour-resistant fiber matrix; (2) preparing an ablation composite material precursor; (3) and (4) compounding. Due to the existence of the aerogel material with the integral structure, the integral heat insulation performance of the ablation material is excellent, and due to the existence of the ceramic filler, the surface of the ablation material has higher scouring resistance.)

1. The preparation method of the heat insulation material is characterized by comprising the following steps of:

(1) preparing an anti-scouring fiber matrix: the first fiber cloth and the second fiber clothSuperposing and needling a fiber mesh blank to form a lower fiber prefabricated body; continuously superposing the second fiber net tire and needling to form a middle fiber preform on the lower fiber preform; continuously stacking at least one layer of the third fiber cloth and the third fiber net tire and needling, wherein each layer of the needling is sprayed with surface reinforcing materials containing ceramic fillers and phenolic binders with the weight of 5-15g/cm²Forming an upper fiber preform; sewing the lower fiber preform, the middle fiber preform and the upper fiber preform by using fibers, and curing to obtain the scour-resistant fiber matrix; wherein the mass ratio of the ceramic filler to the phenolic binder is 100: (5-100); the ceramic filler comprises glass powder, mica powder and talcum powder, and the mass ratio is 100: (0-100): (0-100);

(2) preparing an ablation composite material precursor: uniformly mixing silica sol, ablative resin, an organic solvent and a catalyst to obtain a precursor of the ablative composite material;

(3) compounding: and (3) soaking the anti-scouring fiber matrix in the ablation composite material precursor, and performing gelation treatment and drying and curing treatment to obtain the heat-insulating material.

2. The production method according to claim 1,

when the lower fiber preform is formed, the needling density is 20-30 needles/cm²；

When the middle fiber preform is formed, the needling density is 5-30 needles/cm²(ii) a And/or

When the upper fiber preform is formed, the needling density is 10-40 needles/cm²。

3. The production method according to claim 1,

the thickness of the upper fiber preform is 0.5 mm-5 mm, preferably 1 mm-3 mm; and/or

The thickness of the lower fiber preform is 0.1mm to 1mm, preferably 0.2mm to 0.5 mm.

4. The production method according to claim 1,

the first fiber cloth and the first fiber net tire are made of any one or more of quartz fibers, alumina fibers, mullite fibers, alumina silicate fibers, high silica fibers and silicon carbide fibers; preferably, the fiber diameter is 1 to 20 μm, more preferably 3 to 15 μm;

the second fiber net blank is made of any one or more of zirconia fiber, alumina fiber and silica fiber; and/or

The third fiber cloth and the third fiber net tire are made of any one or more of quartz fibers, alumina fibers, mullite fibers, alumina silicate fibers, high silica fibers and silicon carbide fibers.

5. The production method according to claim 1,

the density of the scour-resistant fiber matrix is 0.28-0.80g/cm³；

The middle fiber preform has a porosity of 80-95%; and/or

The lower fiber preform has a porosity of 40-60%.

6. The production method according to claim 1,

the fiber for sewing is selected from any one or more of alumina fiber, mullite fiber, zirconia fiber and silicon carbide fiber;

preferably, the fiber diameter is 1 to 20 μm, more preferably 3 to 15 μm; and/or

The fiber density is 95-1000tex, more preferably 190-570 tex.

7. The production method according to claim 1,

the ablative resin is any one or more of boron phenolic resin, barium phenolic resin and high-carbon-residue phenolic resin;

the catalyst is any one or more of aniline, hexamethylenetetramine, melamine, p-toluenesulfonic acid, p-toluenesulfonyl chloride and petroleum sulfonic acid; and/or

The organic solvent is any one or more of ethanol, toluene and acetone.

8. The production method according to claim 1,

the gelation treatment was carried out as follows: drying the impregnated material at 80-85 deg.C for 24-72 hr; and/or

The drying and curing treatment is carried out according to the following method:

keeping the temperature at 80-85 ℃ for 1-1.5 hours, heating to 100-110 ℃ for 30-40 minutes and keeping the temperature for 1-1.5 hours; the temperature is continuously raised to 120-130 ℃ for 30-40 minutes and the temperature is kept for 1-1.5 hours.

9. A heat insulating material, characterized by being produced by the production method according to any one of claims 1 to 8.

Technical Field

The invention relates to the technical field of thermal protection materials, in particular to a preparation method of a thermal insulation material and the thermal insulation material prepared by the method.

Background

When the aerospace craft flies in the atmosphere, the outer surface of the aerospace craft bears high heat flow pneumatic scouring, the temperature is up to 1000-10000 ℃, and in order to ensure the safety of the main structure of the aerospace craft and internal instruments and equipment, high-efficiency heat insulation materials are required to prevent external heat flow from being transmitted to the inside.

The traditional ablation material (including low-density ablation material and high-density ablation material) is compounded by taking phenolic resin, epoxy resin, organic silicon resin, polytetrafluoroethylene and the like as ablation matrixes and taking fibers, phenolic microspheres, glass fiber reinforced plastic honeycombs and the like as fillers or reinforcing materials. When high-heat-flow pneumatic flushing is carried out, the high-efficiency ablation effect can be exerted, and the stable state of the internal structure of the aircraft is ensured. However, this type of material has relatively high density and high thermal conductivity, is difficult to ablate/insulate for a long time, is prone to surface peeling and peeling after ablation, and cannot maintain the aerodynamic shape.

Rigid ceramic tiles are the primary solution employed for large area thermal protection of the american space shuttle. It is formed by sintering high-temperature resistant ceramic fibers at high temperature and has higher technical maturity. However, the material has the defects of high brittleness, poor deformability, complex assembly, long period, high maintenance cost and the like, has the highest temperature resistance of only 1600 ℃, and is difficult to meet the thermal protection requirement of future hypersonic aircrafts.

The aerogel heat-insulating material is prepared from a high-temperature-resistant fiber composite aerogel material, and due to the special nanostructure of the aerogel heat-insulating material, the aerogel heat-insulating material has extremely low heat conductivity and is called as a heat-insulating material with the most excellent heat-insulating property. But the mechanical strength is low, so that the surface scour resistance is poor, and the method cannot be used for external thermal protection of an aircraft.

Several technologies for compounding rigid heat insulation tiles and aerogel heat insulation materials were previously developed by our institute, and the research results were patented:

the micro-ablation heat insulation composite material in the Chinese patent application publication No. CN103449825A comprises ablation resin and a rigid heat insulation material, wherein the rigid heat insulation material comprises a ceramic matrix and an aerogel material, the rigid matrix is subjected to vacuum impregnation by using a prepared aerogel precursor solution, and then the rigid heat insulation material is obtained after sol-gel, solvent replacement and supercritical drying. According to the technology, the aerogel material and the ceramic matrix are compounded, so that the high-efficiency heat insulation of the material is realized, and the added ablative resin realizes the high-efficiency ablative heat insulation of the material. However, the thermal insulation properties of the material still leave room for improvement, with the risk of flight reliability.

Chinese patent application publication No. CN108116002A discloses punching aerogel composite thermal insulation material sandwich layer, and laying braided fabric on the upper surface and the lower surface of the sandwich layer respectively, sewing up to obtain the sandwich structure prefabricated member, then using ceramic precursor solution to impregnate the sandwich structure prefabricated member for many times, and obtaining the sandwich structure thermal protection material with high panel strength after sintering. The material is endowed with higher strength by multiple times of impregnation, but the density of the material is greatly improved, and the method is not suitable for application scenes with light requirements on the material.

The invention provides a novel aerogel and fiber matrix compounding process.

Disclosure of Invention

Aiming at the defects or shortcomings in the prior art, the invention provides a preparation method of a heat insulation material and the heat insulation material prepared by the preparation method.

The invention provides the following technical scheme:

a preparation method of a heat insulation material comprises the following steps:

(1) preparing an anti-scouring fiber matrix: a first fiber cloth andsuperposing and needling a first fiber mesh blank to form a lower fiber preform; continuously superposing the second fiber net tire and needling to form a middle fiber preform on the lower fiber preform; continuously stacking at least one layer of the third fiber cloth and the third fiber net tire and needling, wherein each layer of the needling is sprayed with surface reinforcing materials containing ceramic fillers and phenolic binders with the weight of 5-15g/cm²Forming an upper fiber preform; sewing the lower fiber preform, the middle fiber preform and the upper fiber preform by using fibers, and curing to obtain the scour-resistant fiber matrix; wherein the mass ratio of the ceramic filler to the phenolic binder is 100: (5-100); the ceramic filler comprises glass powder, mica powder and talcum powder, and the mass ratio is 100: (0-100): (0-100);

(2) preparing an ablation composite material precursor: uniformly mixing silica sol, ablative resin, an organic solvent and a catalyst to obtain a precursor of the ablative composite material;

(3) compounding: and (3) soaking the anti-scouring fiber matrix in the ablation composite material precursor, and performing gelation treatment and drying and curing treatment to obtain the heat-insulating material.

Preferably, the lower fiber preform is formed with a needling density of 20 to 30 needles/cm²；

When the middle fiber preform is formed, the needling density is 5-30 needles/cm²(ii) a And/or

When the upper fiber preform is formed, the needling density is 10-40 needles/cm²。

Preferably, the thickness of the upper fiber preform is 0.5mm to 5mm, preferably 1mm to 3 mm; and/or

The thickness of the lower fiber preform is 0.1mm to 1mm, preferably 0.2mm to 0.5 mm.

Preferably, the first fiber cloth and the first fiber net tire are made of any one or more of quartz fibers, alumina fibers, mullite fibers, alumina silicate fibers, high silica fibers and silicon carbide fibers; preferably, the fiber diameter is 1 to 20 μm, more preferably 3 to 15 μm;

the second fiber net blank is made of any one or more of zirconia fiber, alumina fiber and silica fiber; and/or

The third fiber cloth and the third fiber net tire are made of any one or more of quartz fibers, alumina fibers, mullite fibers, alumina silicate fibers, high silica fibers and silicon carbide fibers.

Preferably, the density of the scour resistant fibrous matrix is from 0.28 to 0.80g/cm³；

The middle fiber preform has a porosity of 80-95%; and/or

The lower fiber preform has a porosity of 40-60%.

Preferably, the fibers for sewing are selected from any one or more of alumina fibers, mullite fibers, zirconia fibers, silicon carbide fibers;

preferably, the fiber diameter is 1 to 20 μm, more preferably 3 to 15 μm; and/or

The fiber density is 95-1000tex, more preferably 190-570 tex.

Preferably, the ablative resin is any one or more of boron phenolic resin, barium phenolic resin and high carbon residue phenolic resin;

the catalyst is any one or more of aniline, hexamethylenetetramine, melamine, p-toluenesulfonic acid, p-toluenesulfonyl chloride and petroleum sulfonic acid;

the organic solvent is any one or more of ethanol, toluene and acetone.

Preferably, the gelling treatment is carried out as follows: drying the impregnated material at 80-85 deg.C for 24-72 hr; and/or

The drying and curing treatment is carried out according to the following method:

keeping the temperature at 80-85 ℃ for 1-1.5 hours, heating to 100-110 ℃ for 30-40 minutes and keeping the temperature for 1-1.5 hours; the temperature is continuously raised to 120-130 ℃ for 30-40 minutes and the temperature is kept for 1-1.5 hours.

The heat insulation material is prepared by the preparation method provided by the invention.

Advantageous effects

The technical scheme of the invention has the following advantages:

(1) the anti-scouring surface coating aerogel ablative insulation material prepared by the invention has good ablative insulation performance, and the gel curing process forms an organic-inorganic hybrid nano porous insulation material, thereby being beneficial to exerting long-term ablative insulation characteristics.

(2) The anti-scouring surface coating aerogel ablation heat-insulating material prepared by the invention has good dimensional capability, and ceramic layers can be generated by doping ceramic fillers layer by layer under a high-temperature condition, so that the molded surface can be maintained, and airflow can be effectively prevented from being transmitted inwards.

(3) The erosion-resistant surface coating aerogel ablation heat-insulating material prepared by the invention has higher oxidation resistance, and the ceramic filler can prevent the material from being oxidized at high temperature and improve the heat-insulating property.

(4) Can be made into ablation heat-insulating materials with various special shapes and sizes according to the use occasions and parts, in particular to realize a large-size integral heat-insulating layer.

Drawings

FIG. 1 is a schematic flow diagram of the preparation process provided in example 1.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. It is to be understood that the embodiments described are only a few embodiments of the present invention, and not all embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

The present invention provides in a first aspect a method of making a thermal insulation material. Specifically, referring to fig. 1, the preparation method comprises the following steps:

(1) preparing an anti-scouring fiber matrix: superposing and needling a first fiber cloth and a first fiber net tire to form a lower fiber preform; continuously superposing the second fiber net tire and needling to form a middle fiber preform on the lower fiber preform; continuously stacking at least one layer of third fiber cloth and third fiber net tire and needling, wherein a spraying bag is used for needling each layerSurface reinforcing material containing ceramic filler and phenolic aldehyde binder 5-15g/cm²Forming an upper fiber preform; sewing the lower fiber preform, the middle fiber preform and the upper fiber preform by using fibers, and curing to obtain the scour-resistant fiber matrix; wherein the mass ratio of the ceramic filler to the phenolic binder is 100: (5-100); the ceramic filler comprises glass powder, mica powder and talcum powder, and the mass ratio is 100: (0-100): (0-100);

(2) preparing an ablation composite material precursor: uniformly mixing silica sol, ablative resin, an organic solvent and a catalyst to obtain a precursor of the ablative composite material;

(3) compounding: and (3) soaking the anti-scouring fiber matrix in the ablation composite material precursor, and performing gelation treatment and drying and curing treatment to obtain the heat-insulating material.

The invention provides a novel, convenient and efficient preparation method of a heat insulation composite material. According to the preparation method provided by the invention, the ceramic filler is filled into the upper fiber prefabricated body layer by layer when the fiber matrix is prepared, and the ceramic filler doped layer by layer can generate a ceramic layer under a high-temperature condition, so that the molded surface can be maintained, the inward introduction of airflow can be effectively blocked, and the material is endowed with higher oxidation resistance and heat insulation performance. In the subsequent preparation steps, the fiber matrix is soaked in a precursor solution containing ablative resin and silica sol, and then gelation and solidification are carried out, so that the matrix and the ablative resin are compounded, and meanwhile, an inorganic aerogel material is also doped, and the oxidation resistance and the heat insulation performance are further improved.

The surface reinforcing material comprises a ceramic filler and a phenolic adhesive, wherein the mass ratio of the ceramic filler to the phenolic adhesive is 100: (5-100), for example, may be 100:5, 100:10, 100:15, 100:20, 100:25, 100:30, 100:35, 100:40, 100:45, 100:50, 100:55, 100:60, 100:65, 100:70, 100:75, 100:80, 100:85, 100:90, 100:95, 100:100, more preferably 100: (30-100). The inventor finds in research that if the amount of the phenolic binder is too large, the ceramic filler has a small proportion, the ceramic effect is poor, even the ceramic filler cannot be formed, and the molded surface cannot be maintainedTo resist washing. If the dosage of the phenolic aldehyde binder is too small, the binder cannot stick the ceramic filler, and the powder falls off when the inorganic phenolic aldehyde aerogel is compounded in the subsequent steps. The ceramic filler used in the invention comprises glass powder, mica powder and talcum powder, and the mass ratio of the three components is 100: (0-100): (0-100). Namely, the ceramic filler used in the invention can be glass powder, can be glass powder and mica powder, can be glass powder and talcum powder, and can also be glass powder, mica powder and talcum powder. More preferably, the mass ratio of the three is 100: (0-30): (0-30). The amount of surface reinforcing material sprayed on each layer is controlled to be 5-15g/cm²(the area here means the area of the layer), for example, it may be 5g/cm²，6g/cm²，7g/cm²，8g/cm²，9g/cm²，10g/cm²，11g/cm²，12g/cm²，13g/cm²，14g/cm²，15g/cm². If the amount of surface enhancing material sprayed is too great, the density of the material is greater. Moreover, the greater density of the material also results in poor insulating properties. Therefore, the invention controls the spraying amount of the surface reinforcing material to be 5-15g/cm²So as to ensure that the composite material has good dimensional and heat insulation properties and proper density.

In step (1), the curing may be performed as follows: carrying out high-temperature curing on a structure formed by the lower fiber preform, the middle fiber preform and the upper fiber preform which are sewn together, wherein the curing conditions are as follows:

heating to 80-90 deg.C (for example, 80 deg.C, 81 deg.C, 82 deg.C, 83 deg.C, 84 deg.C, 85 deg.C, 86 deg.C, 87 deg.C, 88 deg.C, 89 deg.C, 90 deg.C) within 30-50min (for example, 30min, 35min, 40min, 45min, 50min), and maintaining for 1-1.5 hr;

continuously heating to 100-110 deg.C within 30-50min (for example, 30min, 35min, 40min, 45min, 50min), for example, 100 deg.C, 101 deg.C, 102 deg.C, 103 deg.C, 104 deg.C, 105 deg.C, 106 deg.C, 107 deg.C, 108 deg.C, 109 deg.C, 110 deg.C, and maintaining for 1-1.5 h;

continuously heating to 120-130 deg.C within 30-50min (for example, 30min, 35min, 40min, 45min, 50min), for example, 120 deg.C, 121 deg.C, 122 deg.C, 123 deg.C, 124 deg.C, 125 deg.C, 126 deg.C, 127 deg.C, 128 deg.C, 129 deg.C, 130 deg.C, and maintaining for 1-1.5 h;

continuously heating to 140-150 deg.C within 30-50min (for example, 30min, 35min, 40min, 45min, 50min), for example, 140 deg.C, 141 deg.C, 142 deg.C, 143 deg.C, 144 deg.C, 145 deg.C, 146 deg.C, 147 deg.C, 148 deg.C, 149 deg.C, 150 deg.C, and maintaining for 1-1.5 h; and

heating is continued, and the temperature is raised to 160-170 ℃ within 30-50min (for example, 30min, 35min, 40min, 45min, 50min), for example, 160 ℃, 161 ℃, 162 ℃, 163 ℃, 164 ℃, 165 ℃, 166 ℃, 167 ℃, 168 ℃, 169 ℃, 170 ℃, and the temperature is maintained for 1-1.5 h.

In some preferred embodiments, the lower fiber preform is formed with a needling density of 20 to 30 needles/cm²For example, it may be 20 needles/cm²30 needles/cm²(ii) a When the middle fiber preform is formed, the needling density is 5-30 needles/cm²For example, it may be 5 needles/cm²10 needles/cm²20 needles/cm²30 needles/cm²(ii) a And/or the needling density is 10-40 needles/cm when the upper fiber preform is formed²For example, it may be 10 needles/cm²20 needles/cm²30 needles/cm²40 needles/cm². These needling processes are used to form Z-direction fibers in the upper, middle and lower three-layer fiber preforms while also ensuring that the three-layer fiber preforms have the proper density and porosity.

In some preferred embodiments, the upper fiber preform has a thickness of 0.5mm to 5mm, preferably 1mm to 3mm, and may be, for example, 1mm, 2mm, 3 mm; and/or the lower fiber preform has a thickness of 0.1mm to 1mm, preferably 0.2mm to 0.5mm, and for example, may be 0.2mm, 0.3mm, 0.4mm, 0.5 mm.

In some preferred embodiments, the first fiber cloth and the first fiber web are made of any one or more of quartz fibers, alumina fibers, mullite fibers, alumina silicate fibers, high silica fibers, silicon carbide fibers; preferably, the fiber diameter is 1 to 20 μm, for example, it may be 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 11 μm, 12 μm, 13 μm, 14 μm, 15 μm, 16 μm, 17 μm, 18 μm, 19 μm, 20 μm, more preferably 3 to 15 μm; the second fiber net blank is made of any one or more of zirconia fiber, alumina fiber and silica fiber; and/or the third fiber cloth and the third fiber net tire are made of any one or more of quartz fibers, alumina fibers, mullite fibers, alumina silicate fibers, high silica fibers and silicon carbide fibers.

In some preferred embodiments, the density of the scour resistant fibrous matrix is from 0.28 to 1.20g/cm³(ii) a The middle fiber preform has a porosity of 80-98%; the lower fiber preform has a porosity of 20% to 60%.

In some preferred embodiments, the fibers used for stitching are selected from any one or more of alumina fibers, mullite fibers, zirconia fibers, silicon carbide fibers; preferably, the fibers used for suturing have a diameter of 1 to 20 μm, for example, may be 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 11 μm, 12 μm, 13 μm, 14 μm, 15 μm, 16 μm, 17 μm, 18 μm, 19 μm, 20 μm, more preferably 3 to 15 μm; or the density of the fibers for suturing is 95-1000tex, for example, 95tex, 100tex, 200tex, 300tex, 400tex, 500tex, 600tex, 700tex, 800tex, 900tex, 1000tex, more preferably 190-. The anti-scouring fiber matrix used by the invention is compounded by an upper layer fiber preform, a middle layer fiber preform and a lower layer fiber preform, and partial compounding between layers (and forming Z-direction fibers) can be realized in the needling process, but the firmness of the matrix structure cannot be ensured. In order to solve the problem, the invention adopts the fiber to sew the upper, middle and lower fiber preforms to realize integration. The stitched fibers also form Z-direction fibers in the matrix.

In some preferred embodiments, the ablative resin is any one or more of a borophenolic resin, a barium phenolic resin, a high carbon residue phenolic resin; the catalyst is any one or more of aniline, hexamethylenetetramine, melamine, p-toluenesulfonic acid, p-toluenesulfonyl chloride and petroleum sulfonic acid; the organic solvent is any one or more of ethanol, toluene and acetone.

In some preferred embodiments, the gelation process is carried out as follows: drying the impregnated material at 80-85 deg.C (for example, 80 deg.C, 81 deg.C, 82 deg.C, 83 deg.C, 84 deg.C, 85 deg.C) for 24-72 hr (for example, 24 hr, 36 hr, 48 hr, 60 hr, 72 hr); and/or

The drying and curing treatment is carried out according to the following method: maintaining the temperature at 80-85 deg.C (e.g., 80 deg.C, 81 deg.C, 82 deg.C, 83 deg.C, 84 deg.C, 85 deg.C) for 1-1.5 hours (e.g., 1 hour, 1.5 hours), and maintaining the temperature at 100 deg.C, 110 deg.C (e.g., 100 deg.C, 101 deg.C, 102 deg.C, 103 deg.C, 104 deg.C, 106 deg.C, 107 deg.C, 108 deg.C, 109 deg.C, 110 deg.C) for 30-40 minutes; the temperature is further raised to 120-.

More comprehensively, the preparation method provided by the invention comprises the following steps:

(1) preparing an anti-scouring fiber matrix: superposing and needling a first fiber cloth and a first fiber net tire to form a lower fiber preform; continuously superposing the second fiber net tire and needling to form a middle fiber preform on the lower fiber preform; continuously stacking at least one layer of the third fiber cloth and the third fiber net tire and needling, wherein each layer of the needling is sprayed with surface reinforcing materials containing ceramic fillers and phenolic binders with the weight of 5-15g/cm²Forming an upper fiber preform; sewing the lower fiber preform, the middle fiber preform and the upper fiber preform by using fibers, and curing to obtain the scour-resistant fiber matrix; wherein the mass ratio of the ceramic filler to the phenolic binder is 100: (5-100); the ceramic filler comprises glass powder, mica powder and talcum powder, and the mass ratio is 100: (0-100): (0-100);

the curing may be carried out as follows: carrying out high-temperature curing on a structure formed by the lower fiber preform, the middle fiber preform and the upper fiber preform which are sewn together, wherein the curing conditions are as follows: heating to 80-90 deg.C from room temperature within 30-50min, and maintaining for 1-1.5 h;

continuously heating to 100 ℃ and 110 ℃ within 30-50min, and keeping the temperature for 1-1.5 h;

continuously heating to 120-130 ℃ within 30-50min, and keeping the temperature for 1-1.5 h;

continuously heating to 140-150 ℃ within 30-50min, and keeping the temperature for 1-1.5 h; and

continuously heating to 160-170 ℃ within 30-50min, and keeping the temperature for 1-1.5 h;

when the lower fiber preform is formed, the needling density is 20-30 needles/cm²；

When the middle fiber preform is formed, the needling density is 5-30 needles/cm²(ii) a And/or

When the upper fiber preform is formed, the needling density is 10-40 needles/cm²；

The thickness of the upper fiber preform is 0.5 mm-5 mm, preferably 1 mm-3 mm; the thickness of the lower fiber preform is 0.1 mm-1 mm, preferably 0.2 mm-0.5 mm;

the first fiber cloth and the first fiber net tire are made of any one or more of quartz fibers, alumina fibers, mullite fibers, alumina silicate fibers, high silica fibers and silicon carbide fibers; preferably, the fiber diameter is 1 to 20 μm, more preferably 3 to 15 μm;

the second fiber net blank is made of any one or more of zirconia fiber, alumina fiber and silica fiber;

the third fiber cloth and the third fiber net tire are made of any one or more of quartz fibers, alumina fibers, mullite fibers, alumina silicate fibers, high silica fibers and silicon carbide fibers;

the density of the scour-resistant fiber matrix is 0.28-0.80g/cm³；

The middle fiber preform has a porosity of 80-95%; and/or

The lower fiber preform has a porosity of 40-60%;

the fiber for sewing is selected from any one or more of alumina fiber, mullite fiber, zirconia fiber and silicon carbide fiber; preferably, the fiber diameter is 1 to 20 μm, more preferably 3 to 15 μm; and/or a fiber density of 95 to 1000tex, more preferably 190-570 tex;

(2) preparing an ablation composite material precursor: uniformly mixing silica sol, ablative resin, an organic solvent and a catalyst to obtain a precursor of the ablative composite material; the ablative resin is any one or more of boron phenolic resin, barium phenolic resin and high-carbon-residue phenolic resin; the catalyst is any one or more of aniline, hexamethylenetetramine, melamine, p-toluenesulfonic acid, p-toluenesulfonyl chloride and petroleum sulfonic acid; and/or the organic solvent is any one or more of ethanol, toluene and acetone;

(3) compounding: soaking an anti-scouring fiber matrix in the ablation composite material precursor, and performing gelation treatment, drying and curing treatment to obtain the heat insulation material; the gelation treatment was carried out as follows: drying the impregnated material at 80-85 deg.C for 24-72 hr; the drying and curing treatment is carried out according to the following method: keeping the temperature at 80-85 ℃ for 1-1.5 hours, heating to 100-110 ℃ for 30-40 minutes and keeping the temperature for 1-1.5 hours; the temperature is continuously raised to 120-130 ℃ for 30-40 minutes and the temperature is kept for 1-1.5 hours.

The invention provides a heat-insulating material in a second aspect, and the heat-insulating material is prepared by the preparation method provided by the invention. The anti-scouring surface coating aerogel ablation heat insulation material prepared by the method has important application value in the field of large-area heat protection of aerospace vehicles, and is particularly suitable for large-area heat protection systems of high-Mach-number airplanes.

The following are examples of the present invention.