A hydrophobic aerogel product and preparation method thereof

Abstract

The present invention relates to a hydrophobic aerogel product and a preparation method thereof, comprising the following steps: S1: laying a hydrophobic modification element on the surface of a fiber composite material to be hydrophobized so that the hydrophobic modification element is in close contact with the fiber composite material; S2: winding the fiber composite material to be hydrophobized obtained in S1 and the hydrophobic modification element together to form a roll in which the fiber composite material to be hydrophobized and the hydrophobic modification element are arranged at intervals in a radial direction from the center of a circle; S3: placing the roll in a hydrophobic device and performing a hydrophobic treatment to obtain a hydrophobized fiber composite material; the hydrophobic modification element is always arranged in close contact with the fiber composite material to be hydrophobized so that a hydrophobic reagent on the hydrophobic modification element can be uniformly impregnated into the fiber composite material to be hydrophobized. Moreover, the fiber composite material to be hydrophobized and the hydrophobic modification element are wound into a roll and then placed in the hydrophobic device for hydrophobic treatment, thereby achieving high efficiency in the hydrophobic modification treatment.

Description

Technical Field

[0001] The present invention belongs to the technical field of hydrophobic aerogels, and in particular relates to a hydrophobic aerogel product and a preparation method thereof. Background Art

[0002] Aerogel is a gel material whose dispersion medium is gas. It has a highly cross-linked continuous three-dimensional grid nano hollow structure and a large specific surface area (500-1300m 2 / g), low density (30-150Kg / m 3 Silica aerogels are characterized by high porosity (85%-99%), small average pore size (2-50nm), and lower thermal conductivity (0.01-0.02W / m·K) than room temperature air. They are currently recognized as the solid material with the lowest thermal conductivity. Silica aerogels and their felts possess unique physical and chemical properties, leading to extensive research and application in aerospace, chemical engineering, energy-saving buildings, thermal insulation, catalyst supports, optics, and acoustics.

[0003] The preparation process technology of existing silica aerogel felt is mainly divided into two parts, namely: the preparation of gel and gel drying. Usually, silicon source, solvent, catalyst are used to prepare silica gel to be dried by hydrolysis, gelation, aging, and hydrophobization treatment, and then aerogel is obtained by drying the gel. The hydrophobization method commonly used at present is to place the impregnated felt body in a configured hydrophobization solution after the gel reaction is completed, and then take out the gel felt after hydrophobization treatment and transport it to a drying reactor for drying treatment to prepare aerogel felt. Although this method can obtain hydrophobized silica aerogel felt, in actual production, when the impregnated felt body is placed in a configured hydrophobization solution, the hydrophobization solution is dissolved and infiltrated into the impregnated felt body for hydrophobization modification treatment, resulting in uneven hydrophobization of the impregnated felt body, thereby affecting the effect of the hydrophobic modification of the impregnated felt body, and the hydrophobization treatment efficiency is low. Summary of the Invention

[0004] In view of this, the object of the present invention is to provide a method for preparing a hydrophobic aerogel product to solve the technical problems of poor hydrophobic modification effect and low hydrophobic modification efficiency of impregnated felt in the prior art; in addition, the present invention also provides a hydrophobic aerogel product.

[0005] To achieve the above-mentioned purpose, the technical solution adopted by the surface hydrophobic modification method for aerogel products of the present invention is:

[0006] A method for preparing a hydrophobic aerogel product comprises the following steps:

[0007] S1: Laying a hydrophobic modification member on the surface of the fiber composite material to be hydrophobically treated, so that the hydrophobic modification member is in close contact with the fiber composite material to be hydrophobically treated;

[0008] S2: Winding the fiber composite material to be treated with hydrophobicity and the hydrophobic modification element obtained in S1 together to form a roll in which the fiber composite material to be treated with hydrophobicity and the hydrophobic modification element are alternately arranged in a radial direction from the center of the circle;

[0009] S3: placing the roll in a hydrophobic device for hydrophobic treatment to obtain a hydrophobic fiber composite material.

[0010] Beneficial effect: In the present invention, the hydrophobic modified part is laid on the surface of the fiber composite material to be hydrophobically treated, so that the hydrophobic modified part and the fiber composite material to be hydrophobically treated are arranged in close contact, and then the hydrophobic modified part and the fiber composite material to be hydrophobically treated are wound together to form a roll in which the fiber composite material to be hydrophobically treated and the hydrophobic modified part are arranged at intervals along the radial direction of the center of the circle; in this way, the hydrophobic modified part will always be arranged in close contact with the fiber composite material to be hydrophobically treated, so that the hydrophobic reagent on the hydrophobic modified part can be evenly impregnated into the fiber composite material. Not only that, the fiber composite material and the hydrophobic modified part are wound into a roll, and then placed in a hydrophobic device for hydrophobic treatment, so that the fiber composite material treated with hydrophobicity at one time increases, ensuring that the hydrophobic modification treatment has a higher efficiency.

[0011] Furthermore, the hydrophobic modified member is an air-permeable fiber impregnated with a hydrophobic agent or a cloth impregnated with a hydrophobic agent.

[0012] Beneficial effects: First, the breathable fiber body or cloth serves as a carrier of the hydrophobizing agent and can be impregnated with a certain amount of the hydrophobizing agent; second, the breathable fiber body or cloth is relatively soft and can deform along with the fiber composite material when the fiber composite material is wound and be arranged closely to the fiber composite material; third, the breathable fiber body or cloth has certain pores that allow air to flow through, and has a certain degree of breathability.

[0013] In S1, the fiber composite material is a wet gel felt obtained by impregnating the fiber material with sol and then gelling it.

[0014] Beneficial effects: The hydrophobic modification method of the present invention can be started from the time of wet gel felt.

[0015] Furthermore, the hydrophobic device is a closed container, and a heating device is provided in the closed container. The heating device heats the closed container and controls the temperature at 35-60°C.

[0016] Beneficial effects: The roll is placed in a hydrophobic device, and a heating device is provided in the sealed container to heat the sealed container; first, heating and heating help the hydrophobic agent in the hydrophobic device to evaporate and diffuse, thereby accelerating the impregnation of the hydrophobic agent into the fiber composite material, shortening the time of the hydrophobic treatment, and ensuring the efficiency of the hydrophobic treatment; second, the evaporation and diffusion of the hydrophobic agent makes the hydrophobic agent more evenly impregnated into the fiber composite material, ensuring the quality of the hydrophobic treatment; third, controlling the temperature at 35-60°C not only ensures the diffusion effect of the hydrophobic agent.

[0017] The hydrophobized fiber composite material is dried.

[0018] Advantageous Effects: The hydrophobized composite material can be dried in a hydrophobic device by introducing a supercritical fluid into the device to dry the wet gel felt. Furthermore, the supercritical fluid is supercritical ethanol or supercritical carbon dioxide. By introducing the supercritical fluid into the device, the hydrophobized fiber composite material is dried. Performing both the hydrophobizing and drying steps in the same device avoids damage to the felt during repeated transfer, which could affect the performance of the final product.

[0019] The hydrophobized fiber composite material can also be removed from the hydrophobizing device and dried by placing the removed hydrophobized fiber composite material in a supercritical drying device for drying, drying the hydrophobized fiber composite material under normal pressure, or freeze-drying the hydrophobized fiber composite material. In this way, the hydrophobized fiber composite material can be removed from the hydrophobizing device as quickly as possible, preventing the hydrophobized fiber composite material from occupying the hydrophobizing device for too long, and achieving a rapid turnover of the hydrophobizing device.

[0020] In S1, the fiber composite material is an aerogel felt obtained by impregnating the fiber material with sol, gelling the fiber material, and drying the fiber material.

[0021] Beneficial effects: The hydrophobic modification method of the present invention can be started from the dried aerogel felt, so that the hydrophobic modification method of the present invention has more applicable opportunities.

[0022] In S2, an airtight film is wrapped around the outside of the roll.

[0023] Beneficial effect: The evaporated hydrophobic agent is prevented from escaping from the film, and the hydrophobic agent is ensured to fall on the aerogel felt as much as possible, thereby ensuring that the hydrophobic modification of the aerogel felt has a high quality.

[0024] Furthermore, the hydrophobic device is a sealed container, and the coil is placed in the sealed container to perform hydrophobic modification on the coil.

[0025] Beneficial effects: The roll including the hydrophobic modified part and the fiber composite material is placed in a closed container, and the hydrophobic solution on the hydrophobic modified part gradually diffuses into the fiber composite material, ensuring that the hydrophobic reagent can be evenly impregnated into the fiber composite material; the fiber composite material and the hydrophobic modified part are wound into a roll, and then placed in a hydrophobic device for hydrophobic treatment. The fiber composite material treated with hydrophobic treatment at one time increases, ensuring that the hydrophobic modification treatment has a higher efficiency.

[0026] The surface of the fiber composite material may be provided with multiple layers of hydrophobic modification parts impregnated with a hydrophobizing agent.

[0027] Beneficial effects: The multi-layer hydrophobic modification part can be impregnated with more hydrophobic reagents. At the same time, the multi-layer hydrophobic modification part can increase the distance between the two adjacent layers of fiber composite materials, thereby forming a breathable layer for air circulation between the two adjacent layers of fiber composite materials, thereby ensuring the effective diffusion of the hydrophobic reagent on the hydrophobic modification; if the fiber composite material is a wet gel felt, the multi-layer hydrophobic modification part also acts as a separating layer during the drying process of the wet gel felt, forming a channel for air circulation between the two adjacent layers of fiber composite materials, thereby avoiding poor drying effect of the wet gel felt due to the adhesion of the two adjacent layers of wet gel felt during the drying process.

[0028] The hydrophobic aerogel product is prepared by the preparation method of the hydrophobic aerogel product.

[0029] The prepared hydrophobic aerogel product can also be cut to prepare hydrophobic aerogel sheet products for use in new energy and other fields. DETAILED DESCRIPTION

[0030] The following is a further detailed description of the preparation method of a hydrophobic aerogel product of the present invention in conjunction with specific embodiments:

[0031] Specific embodiment 1: A method for preparing a hydrophobic aerogel product of the present invention comprises the following steps:

[0032] S1: Laying a hydrophobic modification member on the surface of the fiber composite material to be treated with hydrophobicity, so that the hydrophobic modification member is in close contact with the fiber composite material to be treated with hydrophobicity.

[0033] In this embodiment, the fiber composite material is a silica wet gel felt obtained by impregnating the fiber material with silica sol and then gelling it.

[0034] The hydrophobic-modifying element is a breathable fiber impregnated with a hydrophobizing agent. Using a breathable fiber as a carrier for the hydrophobizing agent offers the following advantages: First, the breathable fiber or cloth can be impregnated with a sufficient amount of the agent; second, the breathable fiber or cloth is relatively flexible, allowing it to deform and adhere closely to the fiber composite material during winding; and third, the breathable fiber or cloth has pores that allow air to flow through, providing a certain degree of breathability.

[0035] The hydrophobizing agent is methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane, tetraethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, trimethylethoxysilane, ethyltrimethoxysilane, diethyldimethoxysilane, triethylmethoxysilane, triethylethoxysilane, diethyldiethoxysilane, ethyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri(2-methoxyethoxy)silane, methylvinyldimethoxysilane, vinyltrichlorosilane. One or more of silane, hexamethyldisiloxane, hexamethyldisilazane, heptamethyldisiloxane, heptamethyldisilazane, chloropropyltriethoxysilane, chloropropylmethyldimethoxysilane, dimethoxybis(2-methylpropyl)silane, bistrimethylsiloxymethylsilane, bis(1,2-methyldichlorosilyl)ethane, bis(1,2-trichlorosilyl)ethane, bis(1,2-methyldimethoxysilyl)ethane, bis(1,2-methyldiethoxysilyl)ethane, bis(1,2-trimethoxysilyl)ethane, bis(1,2-triethoxysilyl)ethane, octyltriethoxysilane, trimethylchlorosilane, dimethyldichlorosilane, methyltrichlorosilane, triethylchlorosilane, diethyldichlorosilane, and ethyltrichlorosilane.

[0036] S2: Winding the fiber composite material to be treated with hydrophobicity obtained in S1 together with the hydrophobic modification element to form a roll in which the fiber composite material to be treated with hydrophobicity and the hydrophobic modification element are arranged alternately along the radial direction of the center of the circle. In this embodiment, the hydrophobic modification element is a single layer.

[0037] S3: placing the roll in a hydrophobic device for hydrophobic treatment to obtain a hydrophobic fiber composite material.

[0038] In this embodiment, the hydrophobic device is a closed container, and the closed container is provided with a heating device, and the heating device heats the closed container. In this embodiment, the heating device is a heating tube, and the heating device is embedded in the side wall of the hydrophobic device, and the arrangement of the heating device and the hydrophobic device provided with the heating device are both existing technologies and will not be described in detail here. In other embodiments, the heating device can also be a device that is arranged outside the hydrophobic device and can heat the inside of the hydrophobic device, and the structure of such a heating device is existing technology and will not be described in detail here. During specific use, the closed container is heated by the heating device and is heated to 35-60°C to facilitate the evaporation and diffusion of the hydrophobic agent, thereby accelerating the impregnation of the hydrophobic agent on the silica wet gel felt and shortening the time of the hydrophobic treatment; then the hydrophobicized fiber composite material is dried, specifically, a supercritical fluid is introduced into the hydrophobic device. In this embodiment, the supercritical fluid is supercritical carbon dioxide; the felt body is dried by supercritical carbon dioxide. In this embodiment, under heating conditions, the drying and modification of the silica wet gel felt requires 12-15 hours to obtain a hydrophobic silica aerogel felt. The hydrophobic device in this embodiment has a certain space inside and is provided with a switch door. After the roll is placed in the hydrophobic device, the switch door is closed, and a temporary enclosed space is formed inside the hydrophobic device, thereby facilitating the hydrophobic and drying treatment of the roll inside the hydrophobic device. In this embodiment, the hydrophobic device also includes a temperature detection device. Specifically, the temperature detection device and the hydrophobic device provided with a heating device and a temperature detection device are all prior art and will not be described in detail here.

[0039] In this embodiment, the preparation process of the silicon dioxide wet gel felt is prior art and will not be described in detail here.

[0040] The surface hydrophobic modification method for aerogel products of this embodiment has the following advantages: first, the hydrophobic modification treatment and the drying treatment are carried out simultaneously in the same hydrophobic device, thereby avoiding repeated transportation of the felt body, thereby avoiding damage to the felt body during multiple transportation processes, and affecting the quality of the generated aerogel felt; second, the silica wet gel felt to be hydrophobically treated and the hydrophobic modification member are wound together and rolled into a roll, and then the roll is placed in the hydrophobic device, so that the hydrophobic modification member can fully contact with the silica wet gel felt, so that the hydrophobic agent on the hydrophobic modification member can be evenly impregnated on the silica wet gel felt, ensuring that the hydrophobic modification treatment of the silica wet gel felt has a high quality; third, the hydrophobic device is The sealed container is heated, and the high temperature environment promotes the evaporation and diffusion of the hydrophobicizing agent, accelerates the speed of the hydrophobic modification agent impregnating into the silica wet gel felt, and improves the efficiency of the hydrophobic modification process; Fourth, the hydrophobic modification part acts as a separation layer during the drying process, and the supercritical fluid can pass through the hydrophobic modification part, and the hydrophobic modification part forms an air flow channel between two adjacent layers of silica wet gel felt, thereby avoiding the poor drying effect of the silica wet gel felt due to the adhesion of the two adjacent layers of wet gel felt during the drying process; Fifth, in the process of hydrophobic modification and drying of the silica wet gel felt, one or more rolls including the silica wet gel felt and the hydrophobic modification part can be carried out simultaneously at a time, and the processing efficiency is high. The present invention also protects a hydrophobic aerogel product prepared by this embodiment. Through the above process, the hydrophobicity of the hydrophobic silica aerogel felt obtained is 90%-99.5%.

[0041] Specific embodiment 2: A method for preparing a hydrophobic aerogel product of the present invention comprises the following steps:

[0042] S1: Laying a hydrophobic modification member on the surface of the fiber composite material to be treated with hydrophobicity, so that the hydrophobic modification member is in close contact with the fiber composite material to be treated with hydrophobicity.

[0043] In this embodiment, the fiber composite material is a silica aerogel felt obtained by impregnating the fiber material with silica sol, gelling the fiber material, and drying the fiber material.

[0044] The hydrophobic modified member is an air-permeable fiber body impregnated with a hydrophobizing agent.

[0045] The hydrophobizing agent is methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane, tetraethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, trimethylethoxysilane, ethyltrimethoxysilane, diethyldimethoxysilane, triethylmethoxysilane, triethylethoxysilane, diethyldiethoxysilane, ethyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri(2-methoxyethoxy)silane, methylvinyldimethoxysilane, vinyltrichlorosilane. One or more of silane, hexamethyldisiloxane, hexamethyldisilazane, heptamethyldisiloxane, heptamethyldisilazane, chloropropyltriethoxysilane, chloropropylmethyldimethoxysilane, dimethoxybis(2-methylpropyl)silane, bistrimethylsiloxymethylsilane, bis(1,2-methyldichlorosilyl)ethane, bis(1,2-trichlorosilyl)ethane, bis(1,2-methyldimethoxysilyl)ethane, bis(1,2-methyldiethoxysilyl)ethane, bis(1,2-trimethoxysilyl)ethane, bis(1,2-triethoxysilyl)ethane, octyltriethoxysilane, trimethylchlorosilane, dimethyldichlorosilane, methyltrichlorosilane, triethylchlorosilane, diethyldichlorosilane, and ethyltrichlorosilane.

[0046] S2: Winding the fiber composite material to be treated with hydrophobicity obtained in S1 together with the hydrophobic modification element to form a roll in which the fiber composite material to be treated with hydrophobicity and the hydrophobic modification element are arranged alternately along the radial direction of the center of the circle. In this embodiment, the hydrophobic modification element is a single layer.

[0047] S3: placing the roll in a hydrophobic device for hydrophobic treatment to obtain a hydrophobic fiber composite material.

[0048] In this embodiment, the hydrophobic device is a closed container, and there is a certain space inside the hydrophobic device for placing the roll including the hydrophobic modification part and the fiber composite material, and the hydrophobic device is provided with a switch door. After the roll is placed in the hydrophobic device, the switch door is closed, and a temporary closed space is formed inside the hydrophobic device, thereby facilitating the hydrophobic treatment of the roll inside the hydrophobic device; the roll including the hydrophobic modification part and the silica aerogel felt is placed in the hydrophobic device, and hydrophobic modification treatment is performed under natural conditions. The hydrophobic modification time is 20-40 hours to obtain a hydrophobic silica aerogel felt.

[0049] In this embodiment, the sealed container is provided with a heating device, and the heating device heats the sealed container. In this embodiment, the heating device is a heating tube, and the heating device is embedded in the side wall of the hydrophobic device. The setting method of the heating device and the hydrophobic device provided with the heating device are both prior art and will not be described in detail here. In other embodiments, the heating device can also be a device provided outside the hydrophobic device and capable of heating the inside of the hydrophobic device. In addition, the structure of such a heating device is prior art and will not be described in detail here. When used specifically, the sealed container is heated by the heating device and is heated to 35-60°C to facilitate the evaporation and diffusion of the hydrophobic agent, thereby accelerating the impregnation of the hydrophobic agent on the silica aerogel felt and shortening the time of the hydrophobic treatment.

[0050] In order to further shorten the time of hydrophobic treatment, in this embodiment, after the end of S2 and before the start of S3, the roll including the fiber composite material and the hydrophobic modification part is tightly wrapped with an airtight film and then placed in a hydrophobic device. In this way, the evaporated hydrophobic agent can be prevented from escaping from the film, ensuring that the hydrophobic agent falls on the silica aerogel felt as much as possible, thereby ensuring that the hydrophobic modification of the silica aerogel felt has a high quality.

[0051] The surface hydrophobic modification method for aerogel products of this embodiment has the following advantages: first, the silica aerogel felt to be hydrophobically treated and the hydrophobic modification member are wound together and rolled into a roll, and then the roll is placed in a hydrophobic device, so that the hydrophobic modification member can fully contact the silica aerogel felt, so that the hydrophobic modification agent on the hydrophobic modification member can be evenly impregnated on the silica aerogel felt, ensuring that the hydrophobic modification treatment of the silica aerogel felt has a high quality; second, the hydrophobic modification agent evaporates and diffuses in a closed environment, making the hydrophobic treatment of the felt more uniform, and the evaporated and diffused hydrophobic modification agent is only in the hydrophobic device, preventing the hydrophobic agent gas from escaping, shortening the hydrophobic treatment time of the silica aerogel felt, thereby ensuring that the hydrophobic modification treatment of the silica aerogel felt has a high efficiency and high quality; third, in the process of hydrophobic modification of the silica aerogel felt, one or more rolls including the silica aerogel felt and the hydrophobic modification member can be carried out simultaneously at a time, and the treatment efficiency is high. The present invention also protects a hydrophobic aerogel product prepared by this embodiment. Through the above process, the hydrophobic silica aerogel felt obtained has a hydrophobicity of 90%-99.5%.

[0052] In this embodiment, the aerogel felt to be hydrophobized is a rolled aerogel felt. Compared to the conventional method of placing the rolled aerogel felt in a hydrophobic modifier for hydrophobic modification, this method can avoid the poor internal hydrophobicity and uneven hydrophobicity caused by too many layers of fiber composite material. The preparation process of the aerogel felt is conventional and will not be described in detail here.

[0053] In the above embodiments, the fiber composite material is an alumina wet gel felt obtained by impregnating the fiber material with alumina sol and then gelling it, or a silica-alumina composite wet gel felt obtained by impregnating the fiber material with alumina composite sol and then gelling it, or an alumina aerogel felt obtained by impregnating the fiber material with alumina sol and then gelling and drying it, or a silica-alumina composite aerogel felt obtained by impregnating the fiber material with alumina composite sol and then gelling and drying it.

[0054] In the above embodiment, the hydrophobic modified member is a breathable fiber body impregnated with a hydrophobic agent; in other embodiments, the hydrophobic modified member is a cloth impregnated with a hydrophobic agent.

[0055] In the above embodiment, supercritical fluid is introduced into the hydrophobic device; in other embodiments, when the wet gel felt is dried and hydrophobized, supercritical fluid may not be introduced into the hydrophobic device.

[0056] In the above embodiment, the supercritical fluid is supercritical carbon dioxide; in other embodiments, the supercritical fluid may also be supercritical ethanol.

[0057] In the above embodiments, the hydrophobic composite material is dried in a hydrophobic device. In other embodiments, the hydrophobic fiber composite material in the hydrophobic device can also be taken out and dried by placing the taken out hydrophobic fiber composite material in a supercritical drying device for drying, or drying the hydrophobic fiber composite material at normal pressure, or freeze-drying the hydrophobic fiber composite material.

[0058] In the above embodiment, the hydrophobic modification component is a single layer. In other embodiments, the hydrophobic modification component can also be provided in multiple layers. The hydrophobic modification component provided in multiple layers can be impregnated with more hydrophobicizing agents. At the same time, the multi-layer hydrophobic modification component can increase the distance between the two adjacent layers of fiber composite materials, thereby forming a breathable layer for air circulation between the two adjacent layers of fiber composite materials, thereby ensuring the effective diffusion of the hydrophobic agent on the hydrophobic modification; if the fiber composite material is a wet gel felt, the multi-layer hydrophobic modification component also acts as a separating layer during the drying process of the wet gel felt, forming a channel for air circulation between the two adjacent layers of fiber composite materials, thereby avoiding poor drying effect of the wet gel felt due to adhesion between the two adjacent layers of wet gel felt during the drying process.

[0059] In the specific embodiment 2, the sealed container is provided with a heating device, and the heating device heats the sealed container; in other embodiments, the sealed container may not be provided with a heating device.

[0060] In specific embodiment 2, the roll comprising the fiber composite material and the hydrophobic modified component is tightly wrapped with an airtight film; in other embodiments, the roll comprising the fiber composite material and the hydrophobic modified component can also be directly placed on the hydrophobic device without being tightly wrapped with an airtight film.

Claims

1. A method for preparing a hydrophobic aerogel product, characterized in that: The following steps are involved: S1: Laying a hydrophobic modification member on the surface of the fiber composite material to be hydrophobically treated, so that the hydrophobic modification member is in close contact with the fiber composite material to be hydrophobically treated; S2: Winding the fiber composite material to be treated with hydrophobicity and the hydrophobic modification element obtained in S1 together to form a roll in which the fiber composite material to be treated with hydrophobicity and the hydrophobic modification element are alternately arranged in a radial direction from the center of the circle; S3: placing the roll in a hydrophobic device for hydrophobic treatment to obtain a hydrophobic fiber composite material; In S1, the hydrophobic modified member is an air-permeable fiber impregnated with a hydrophobic agent or a cloth impregnated with a hydrophobic agent; In S1, the fiber composite material is a wet gel felt obtained by impregnating the fiber material with a sol and then gelling it, or an aerogel felt obtained by impregnating the fiber material with a sol and then gelling it and drying it; In S3, the temperature of the hydrophobization treatment is controlled at 35-60°C; After S3, the hydrophobized fiber composite material is dried.

2. The method for preparing a hydrophobic aerogel product according to claim 1, wherein: In S2, an airtight film is wrapped around the outside of the roll.

3. The method for preparing a hydrophobic aerogel product according to claim 2, wherein: The hydrophobic device is a closed container, which is provided with a heating device for heating the closed container.

4. The method for preparing a hydrophobic aerogel product according to claim 1, wherein: The surface of the fiber composite material may be provided with multiple layers of hydrophobic modification parts impregnated with a hydrophobizing agent.

5. A hydrophobic aerogel product prepared by the method for preparing a hydrophobic aerogel product according to any one of claims 1 to 4.