CN116446106A

CN116446106A - Equipment for preparing gel felt, preparation method of gel felt and aerogel felt

Info

Publication number: CN116446106A
Application number: CN202310461168.1A
Authority: CN
Inventors: 张继承; 刘喜宗; 张东生; 吴宇; 董会娜
Original assignee: Gongyi Van Research Yihui Composite Material Co Ltd
Current assignee: Gongyi Van Research Yihui Composite Material Co Ltd
Priority date: 2023-04-26
Filing date: 2023-04-26
Publication date: 2023-07-18

Abstract

The invention provides equipment for preparing a gel felt, a preparation method of the gel felt and an aerogel felt, wherein the method can move a fiber felt combined with sol under the condition of a gas-wet felt interface through the action of traction force and gel in the moving process, and a moving element is not arranged in the gelling process after the fiber felt is combined with the sol, so that the problem that gel blocks are retained on the moving element due to the surface tension between the moving element and the gel felt or the fiber felt combined with the sol and the quality of an aerogel felt is not influenced is solved. The gel felt prepared by the method has more uniform whole-roll performance, the density of the finally prepared whole-roll aerogel felt is more uniform, the density change of different positions in the whole-roll aerogel felt is less than 15%, the heat insulation performance of the whole-roll aerogel felt is more uniform, and the heat insulation performance change of different positions in the whole-roll aerogel felt is less than 15%.

Description

Equipment for preparing gel felt, preparation method of gel felt and aerogel felt

Technical Field

The invention belongs to the field of gel felts and preparation thereof, relates to equipment for preparing the gel felts and a preparation method thereof, and also relates to an aerogel felt and a preparation method thereof, in particular to a solvent-filled gel felt prepared in a continuous mode, equipment for preparing the gel felt and an aerogel felt related product prepared by the gel felt.

Background

Aerogel refers to a solid structure that does not collapse after the liquid in the gel structure has been replaced with a gas. The silica aerogel is a continuous three-dimensional network structure formed by mutually polymerizing nano-scale particles, and has special nano-scale micropores and a skeleton structure, so that the thermal conductivity, the convection heat transfer efficiency and the radiation heat transfer efficiency are effectively limited, and therefore, the aerogel has very low heat conductivity and is a solid material with the lowest heat conductivity in the world at present.

Typically, aerogels are obtained by preparing hydrogels from silica precursors such as water glass or tetraethyl orthosilicate (TEOS) and removing the liquid components of the hydrogels without destroying the microstructure. Silica aerogel includes three conventional forms of powder, granules and monoliths. The silica aerogel is combined with fibers to prepare a aerogel felt or a aerogel sheet, and the silica aerogel is applied to the fields of industrial heat preservation and the like.

The aerogel is prepared by taking fiber felts such as glass fiber or ceramic fiber as a base material, combining the prepared sol with the fiber felts in a dipping or spraying mode, performing sol-gel reaction on the sol in the base material to form a gel felt, then performing chemical modification on the gel felt, and finally preparing the aerogel felt through a supercritical or normal pressure drying process.

A common method of manufacturing an aerogel blanket includes a conveyor belt, a silica sol supply part, and a catalyst supply part, one of which is to spray silica sol from the silica sol supply part onto the surface of a fiber blanket on the conveyor belt to impregnate the silica sol, and then the catalyst supply part sprays a gelling catalyst onto the surface of the fiber blanket on the conveyor belt to gel the silica sol. Another manufacturing method is to mix silica sol and a gelling catalyst first, and then distribute the mixed catalytic sol to the surface of the fiber mat between two conveyor belts at a preset rate to obtain a gel mat. Finally, the gel felt is cut into sheets by a cutting member.

The two manufacturing methods are realized by conveying the fiber mats through a conveyor belt, and the conveyor belt is a device which occupies a relatively large transverse space and can cause the whole equipment to be relatively large in volume; further, the gel felt is continuously produced by the way of retaining the glue and gelling the conveyor belt, and the gel blocks which are not bonded to the fiber felt are inevitably remained on the conveyor belt. In the continuous production process of the aerogel felt, gel stays on a conveyor belt in the gel process of the catalyzed sol on the conveyor belt to form gel solid blocks (or powder), and the adhered gel solid blocks can cause the situation that the upper and lower layers of felt bodies with gel block areas are wrinkled and concave pits, so that the quality of the aerogel felt products produced subsequently is affected; on the other hand, because the gel stays on the conveyor belt, the surface of the gel material is locally not impregnated with the sol, so that the surface defect of the aerogel material is caused, and the heat insulation performance of the aerogel material is affected.

Chinese patent document CN100540257C discloses continuously combining a sol and a gel inducing agent to form a catalyzed sol, dispensing the catalyzed sol onto a moving element at a predetermined rate to form a gel sheet, and gelling the catalyzed sol onto the moving element at the predetermined rate. As described above, in actual production, the gel stays on the conveyor belt during the gel process of the catalyzed sol on the conveyor belt to form gel solid blocks (or powder), which can cause the technological failure of the mechanical operation treatment device, the gel solid blocks on the conveyor belt can be partially adhered to the gel felt, the gel felt can be rolled or cut into gel sheets to be stacked after continuous production of the gel felt to carry out batch ageing, drying and other processes, and the adhered gel solid blocks can cause the situation that the upper and lower layers of felt bodies with gel block areas have folds, pits and breaks, so that the quality of the aerogel felt products produced subsequently is affected.

Disclosure of Invention

The invention aims to provide equipment for preparing a gel felt, a preparation method of the gel felt and an aerogel felt, wherein the equipment and the preparation method are used for preparing the gel felt (or defined as wet gel felt) filled with a solvent in a continuous mode, so that the influence of stagnation and agglomeration of sol combined with a fiber felt on the surface of a moving element in the gelation process on the gel felt and the aerogel felt prepared later is eliminated.

The invention aims at realizing the following technical scheme:

a method for preparing a gel felt, in particular to a continuous preparation method of the gel felt, which comprises the following steps:

s1, combining a fiber felt with sol to obtain a wet felt;

s2, moving the wet felt along the horizontal direction or along the direction which forms an included angle of less than 90 degrees with the horizontal direction under the condition of a gas-wet felt interface, so that the sol forms gel, and the gel felt is obtained.

The invention also provides a gel felt prepared by the method.

The invention also provides a preparation method of the aerogel felt, which comprises the following steps:

a) The gel felt is prepared by adopting the preparation method of the gel felt;

b) Optionally, subjecting the gel-mat obtained in step a) to at least one of an ageing treatment, a modification treatment and a solvent replacement treatment;

c) And c), drying the gel felt obtained in the step a) or the gel felt obtained in the step b) to obtain the aerogel felt.

The invention also provides an aerogel felt prepared by the preparation method of the aerogel felt.

The present invention also provides an apparatus for preparing a gel-felt, the apparatus comprising:

a bonding device for bonding the sol and the fiber mat;

A felt body supply device connected to one side of the bonding device, which continuously supplies the unwound fiber felt to the bonding device by unwinding the fiber felt;

a sol injection device for injecting a sol into the bonding device so as to bond with the fiber mat in the bonding device with the sol;

the gel felt rolling device or the clamping conveying device is positioned at the other side of the combining device and forms a length difference or a height difference with the combining device, and the length difference or the height difference is required to enable the fiber felt combined with the sol to gel in the moving process to form the gel felt; the gel felt rolling device is used for rolling the gel felt into a rolled gel felt and providing traction force for the gel felt; and the clamping and conveying device is used for clamping the gel felt and providing traction force for the gel felt.

The invention has the following beneficial effects:

according to the preparation method of the gel felt, the fiber felt combined with the sol can be moved under the condition of a gas-wet felt interface under the action of traction force and is gelled in the moving process, and a moving element is not arranged in the gelling process after the fiber felt is combined with the sol, so that the problem that gel blocks are remained on the moving element due to the surface tension between the moving element and the gel felt or the fiber felt combined with the sol, and the quality of an aerogel felt product is influenced is solved. Compared with the gel felt prepared by moving the traction force action along the horizontal direction or moving the traction force action along the direction which forms an included angle smaller than 90 degrees with the horizontal direction along the vertical direction under the action of gravity, the gel felt prepared by moving the traction force action along the horizontal direction has more uniform whole roll performance, the density of the finally prepared whole roll aerogel felt is more uniform, the density change of different positions in the whole roll aerogel felt is smaller than 15%, the heat insulation performance of the whole roll aerogel felt is more uniform, and the heat insulation performance change of different positions in the whole roll aerogel felt is smaller than 15%.

Drawings

FIG. 1 is a flow chart of a method of making a silica aerogel blanket according to the present invention;

FIG. 2 is a schematic diagram of example 1 of the present invention;

FIG. 3 is a schematic diagram of embodiment 4 of the present invention;

FIG. 4 is a schematic diagram of example 7 of the present invention;

FIG. 5 is a schematic diagram of embodiment 10 of the present invention;

FIG. 6 is a schematic diagram of embodiment 13 of the present invention;

FIG. 7 is a schematic diagram of embodiment 16 of the present invention;

FIG. 8 is a schematic diagram of embodiment 19 of the present invention;

reference numerals in fig. 1-8: 1. a sol injection device free of gel catalyst; 2. a gel catalyst injection device; 3. a flow control device; 4. a mixing and stirring tank; 5. a felt supply device; 6. a fibrous mat; 7. a carrier roller; 8. a bonding device; 9. a squeeze roll; 10. winding equipment; 11. a traction mechanism; 12. cutting equipment; 13. gel felt; 14. a spraying device; 15. clamping the conveying equipment; 16. and a bracket mechanism.

Detailed Description

As described above, the present invention provides a method for preparing a gel felt, in particular, a continuous preparation method of a gel felt, which comprises:

s1, combining a fiber felt with sol to obtain a wet felt;

The gel felt of the present invention means, unless otherwise specified, a wet gel felt, i.e., a wet gel felt in which a sol has been completely gelled to form a gel, and the inside is filled with a solvent, without being dried.

In one embodiment, in step S2, the wet felt is gelled without contacting any moving element, so that the prepared gel felt has good control and no wrinkling and dishing effects.

In one embodiment, in step S2, the "gas-wet mat interface" refers to the interface at which the wet mat and gas contact, and the wet mat does not contact any moving elements during movement, only with the gas and optionally the support mechanism.

In one embodiment, in step S2, the contact area of the gas and wet mat is 90% to 100%, such as 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or 100%; when the contact area of the gas and the wet felt is 90% -100%, the contact area of the bracket mechanism and the wet felt is 0-10%, the bracket mechanism can provide a certain support for the wet felt, and the wet felt is prevented from being pulled, deformed or torn and damaged when the wet felt is only supported by traction force. Because the support mechanism does not move, friction exists between the support mechanism and the wet felt, the contact area between the support mechanism and the wet felt is 0-10%, and the wet felt pulling deformation caused by overlarge friction between the support mechanism and the wet felt can be avoided.

In one embodiment, in step S2, the gas is air, preferably air at 20 to 35 ℃, and under such conditions, the gelation time of the sol can be ensured to be relatively suitable, and the effect of low cost and easy realization can be obtained.

In one embodiment, in step S2, the gas-wet felt interface may be irradiated and heated during the moving process, so as to accelerate the gelation process of the wet felt, shorten the gelation time, and be beneficial to the sol in the wet felt to remain on the fiber felt during and after the winding process, and prevent the sol from leaking.

In some embodiments, the temperature of the radiant heating is 20 to 50 ℃.

In one embodiment, in step S2, the wet mat is moved in a single layer or multiple layer stack under gas-wet mat interface conditions. If the wet felt is a single layer, the upper surface and the lower surface of the wet felt are contacted with gas to form two gas-wet felt interfaces; in the case of multi-layer stacking, the upper and lower surfaces of the multi-layer stacked wet mat are in contact with the gas, and two gas-wet mat interfaces are also formed.

In one embodiment, the multi-layer stacked wet felts are gelled in the moving process and rolled into a rolled gel felt in a multi-layer stacked mode, and because the multi-layer stacked wet felts are rolled or cut together, the stress directions and the stress sizes of the multi-layer stacked wet felts are the same in the moving process, the upper surface and the lower surface of the multi-layer stacked wet felts are in contact with gas, and only an upper gas-wet felt interface and a lower gas-wet felt interface are formed.

In one embodiment, the multi-layer stacked wet felts are gelled in the moving process, the multi-layer stacked gel felts are respectively rolled or cut before rolling, and under the action of traction force and gravity, part of the multi-layer stacked wet felts are in contact with gas in the moving process to form an upper surface and a lower surface, part of the wet felts are separated from each other, and the upper surface and the lower surface of each layer of wet felts are in contact with the gas due to different forces applied to the gel felts by different rolling equipment or cutting equipment.

In one embodiment, the multi-layer stacked wet felts are gelled in the moving process, the multi-layer stacked gel felts are separated to be rolled or cut respectively before rolling, and the upper surface and the lower surface of each layer of wet felts are contacted with gas under the action of traction force and gravity due to different forces applied to the gel felts by different rolling devices or cutting devices.

In one embodiment, step S2 specifically includes the steps of:

s2-1, moving the wet felt along the horizontal direction under the action of traction force, and gelling sol in the moving process to form a gel felt; or alternatively, the process may be performed,

s2-2, the wet felt moves along a direction which forms an included angle of less than 90 degrees with the horizontal direction under the action of traction force, and the sol is gelled to form a gel felt in the moving process.

In one embodiment, in steps S2-1 and S2-2, the wet mat is moved in the direction under traction to maintain the fiber mat in constant motion, facilitating control of the gelation process.

In one embodiment, in step S2-2, the arbitrary included angle has a degree of more than 0 to less than 90 °, for example, 5 °, 10 °, 15 °, 20 °, 25 °, 30 °, 35 °, 40 °, 45 °, 50 °, 55 °, 60 °, 65 °, 70 °, 75 °, 80 °, or 85 °.

The beneficial effects of the technical scheme are that: according to the preparation method of the gel felt, the fiber felt combined with the sol can be moved under the condition of a gas-wet felt interface under the action of traction force and is gelled in the moving process, and a moving element is not arranged in the gelling process after the fiber felt is combined with the sol, so that the problem that gel blocks are remained on the moving element due to the surface tension between the moving element and the gel felt or the fiber felt combined with the sol, and the quality of an aerogel felt product is influenced is solved.

It is found that the wet felt (combined with the fiber felt after the sol) has different absorption and storage conditions on the sol when moving along the horizontal direction and when moving along the vertical direction, the loss amount of the sizing solution when moving along the horizontal direction of the combined fiber felt after the sol is smaller than that when moving along the vertical direction, and the gel felt prepared by moving along the horizontal direction or moving along the direction with any included angle smaller than 90 degrees with the horizontal direction under the action of the traction force of the invention has more uniform whole-roll performance compared with the gel felt prepared by moving along the vertical direction under the action of gravity, the density of the finally prepared whole-roll aerogel felt is more uniform, the density variation of different positions in the whole-roll aerogel felt is less than 15%, the heat insulation performance of the whole-roll aerogel felt is more uniform, and the heat insulation performance variation of different positions in the whole-roll aerogel felt is less than 15%.

In one embodiment, step S1 includes the steps of:

s1-1, preparing a combination device containing sol;

s1-2, unreeling the fiber felt, passing the unreeled fiber felt through a bonding device, and bonding the sol and the fiber felt in the bonding device before sol-gel to form the sol-bonded fiber felt, namely, the wet felt.

In one embodiment, the sol may be a sol containing no gel catalyst and a solvent containing a gel catalyst, preferably a sol containing a gel catalyst, and the sol containing a gel catalyst is defined as a catalytic sol in the present invention, which is formed by mixing a sol and a gel catalyst.

In one embodiment, the gel catalyst is used to catalyze the polycondensation of a sol to form a gel.

In one embodiment, the sol containing the gel catalyst can obviously shorten the gel time, and the shortening of the gel time is beneficial to accelerating the gel viscosity increase gelation transition process, so that the loss of the sol combined with the fiber mat when the non-moving element is used as a gel mold is reduced at low viscosity, and the sol in the wet mat is beneficial to the retention of the sol on the fiber mat in the moving process and after winding under the action of traction force.

In one embodiment, in step S1-1, the sol and the gel catalyst without the gel catalyst are injected into the combining device separately, and mixed in the combining device to form a catalytic sol. It has been found that the separate injection of the sol without gel catalyst and the gel catalyst into the bonding apparatus can be controlled by controlling the respective control means to prevent the viscosity of the catalytic sol from increasing before impregnation, which is advantageous for controlling the gel time and the physical properties of the aerogel.

In one embodiment, in step S1-1, the sol without the gel catalyst and the gel catalyst are thoroughly stirred and mixed by a mixing and stirring tank to form a catalytic sol, and then the catalytic sol is injected into the combining device. It was found that a uniform gel reaction can be obtained when the catalytic sol is re-injected into the bonding apparatus after thorough mixing.

In one embodiment, the gel catalyst free sol is a sol known in the art that can be prepared into a gel felt, and illustratively the gel catalyst free sol comprises a silica sol, an alumina sol, or a silica alumina composite sol.

In one embodiment, the sol may be prepared as an aerogel.

In one embodiment, the gel catalyst is a basic catalyst, the basic catalyst is used for promoting gelation of the sol by increasing the pH of the sol, and the basic catalyst is selected from inorganic base and/or organic base.

For silica sols, the gel catalyst is selected from inorganic and/or organic bases; the inorganic base is sodium hydroxide, potassium hydroxide and ammonia waterAny one or more of ammonium fluoride, ammonium bicarbonate, sodium carbonate and sodium bicarbonate; the organic base is any one or more of ethanolamine, diethanolamine, methylamine, dimethylamine, ethylamine, diethylamine, propylamine, dipropylamine, isopropanolamine, aniline, o-phenylenediamine, m-phenylenediamine and p-phenylenediamine. Ammonia water is the most commonly used basic catalyst, but NaF or NH ₄ The Lewis bases such as F and the like are more advantageous for the catalytic gel with MTMS as a precursor.

For alumina sol, the gel catalyst comprises one or more of sodium hydroxide, potassium hydroxide, ammonia water and ammonium fluoride.

In one embodiment, the gel catalyst is added to the catalytic sol in an amount to ensure that the pH of the catalytic sol is between 7 and 11. When the pH of the catalytic sol exceeds the above range, the gel rate may be too slow; more preferably, the gel catalyst is added to the catalytic sol in an amount to ensure a pH of 7 to 8 in the catalytic sol, at which time the produced aerogel has a porosity of more than 95% and the gel time is extremely fast.

In one embodiment, the silica sol is prepared from a starting material comprising a precursor of a silica sol, an alcohol, and water.

In one embodiment, the silica sol may also include a hydrolysis catalyst, which may or may not be added.

In one embodiment, the silica sol is prepared from the following components in parts by mole:

1 molar part of a precursor of a silica sol;

2-60 mol parts of alcohol;

0.05 to 30 parts by mole of water.

In one embodiment, the precursor of the silica sol is an alkyl orthosilicate and/or an alkyl alkoxysilane, the alkyl orthosilicate including one or two of tetramethyl orthosilicate, tetraethyl orthosilicate, methyltriethyl orthosilicate, dimethyldiethyl orthosilicate, tetrapropyl orthosilicate, tetraisopropyl orthosilicate, tetrabutyl orthosilicate, tetra-sec-butyl orthosilicate, tetra-tert-butyl orthosilicate, tetrahexyl orthosilicate, tetracyclohexyl orthosilicate, and tetradodecyl orthosilicate; the alkyl alkoxy silane comprises one or more of methyl trimethoxy silane, dimethyl dimethoxy silane, methyl triethoxy silane, dimethyl diethoxy silane, vinyl triethoxy silane, propyl trimethoxy silane and propyl triethoxy silane. Preferably, the precursor of the silica sol is selected from tetramethyl orthosilicate, tetraethyl orthosilicate or mixtures thereof.

In one embodiment of the present invention, in one embodiment, the alcohol is at least one of methanol, ethanol, isopropanol and butanol.

In one embodiment, the hydrolysis catalyst is an acid catalyst, and the acid catalyst is used as the hydrolysis catalyst to catalyze the reaction process of forming silica sol by hydrolyzing the precursor of the silica sol, and the acid catalyst comprises one or more selected from nitric acid, hydrochloric acid and hydrofluoric acid.

In one embodiment, the precursor of the silica sol, the alcohol and the hydrolysis catalyst are added in an amount to ensure that the pH of the mixture of the precursor of the silica sol, the alcohol and the water is 2 to 6, and more preferably, the pH of the mixture of the precursor of the silica sol, the alcohol and the water is 4 to 6.

In one embodiment, the method of preparing a silica sol-based catalytic sol comprises the steps of:

mixing a precursor of the silica sol, alcohol and water, adding a hydrolysis catalyst, and adding a gel catalyst after the hydrolysis catalyst catalyzes the precursor of the silica sol to hydrolyze to form the silica sol; or alternatively, the process may be performed,

mixing a precursor of the silica sol, alcohol and water, and adding a gel catalyst after the precursor of the silica sol is hydrolyzed to form the silica sol.

In one embodiment, the alumina sol is prepared from a starting material comprising a precursor of an alumina sol, a chelating agent, an alcohol, and water.

In one embodiment, the alumina sol is prepared from the following components in molar ratio:

1 molar part of precursor of alumina sol;

0.001 to 0.06 molar parts of chelating agent;

4-32 mole parts of alcohol;

0.6 to 4 mole parts of water.

In one embodiment, the precursor of the alumina sol comprises one or a combination of more than two of aluminum isopropoxide, aluminum sec-butoxide, aluminum nitrate.

In one embodiment, the chelating agent comprises one or a combination of more than two of acetylacetone, acetic acid, and ethyl acetoacetate.

In one embodiment, the alcohol comprises one or a combination of two or more of ethanol, isopropanol, and n-butanol.

In one embodiment, the silica-alumina composite sol includes the silica sol described above and the alumina sol described above.

In one embodiment, the silica sol precursor and the alumina sol precursor in the alumina sol are present in a molar ratio of (1-8): 1-8.

In one embodiment, the silica sol is defined as described above.

In one embodiment, the alumina sol is defined as described above.

In one embodiment, the fibers in the fiber mat are one or a combination of two or more of the group consisting of the following fibrous materials: quartz fibers, glass fibers, silica-rich fibers, carbon fibers, pre-oxidized fiber, mullite fibers, basalt fibers, silicon carbide fibers, silicon nitride fibers, aluminum oxide fibers, boron nitride fibers, aluminum silicate fiber mats (ceramic fiber mats).

In one embodiment, in step S1-2: the bonding includes combining the continuous fiber mat with a sol by pouring, brushing, dipping or spraying the continuous fiber mat through a combining device.

If the continuous mat is passed through the bonding apparatus by pouring, brushing or spraying, the bonding apparatus may be considered as a container for holding the sol or as a bonding station where the sol is sprayed (or poured or brushed) onto the continuously moving mat in the bonding apparatus and bonded with the catalytic sol.

Specifically, a continuously moving fiber mat is immersed in a bonding apparatus to be bonded with a sol.

In one embodiment, if the sol catalyst in the bonding apparatus is formed by injecting the sol catalyst without gel catalyst and the gel catalyst into the bonding apparatus and mixing them in the bonding apparatus, there may be a problem that the sol catalyst without gel catalyst and the gel catalyst combined with the fiber mat may be insufficiently mixed by injecting the sol catalyst without gel catalyst into the bonding apparatus and mixing them in the bonding apparatus, and then the mixing of the sol catalyst without gel catalyst and the gel catalyst may be supplemented by providing squeeze rolls in the bonding apparatus, that is, the formation of the sol catalyst may be promoted.

In one embodiment, if the sol without gel catalyst and the gel catalyst in the combining device are fully stirred and mixed by the mixing and stirring tank so as to be fully mixed, and then the catalytic sol is injected into the combining device, the problem of insufficient mixing is avoided, the catalytic sol can be directly used, and the subsequent uniform gel reaction can be ensured.

In one embodiment, passing the continuous fiber mat through a bonding apparatus to bond the sol refers to the continuous moving fiber mat being bonded to the gel catalyst by dipping into the bonding apparatus with the unmixed sol without gel catalyst. The impregnation can be more sufficient by soaking. The continuous moving fiber mat may have a problem of insufficient mixing of the sol without gel catalyst and the gel catalyst combined with the fiber mat by immersing the fiber mat into the combining apparatus to combine with the sol without gel catalyst, and the sol without gel green lake additive may be supplemented to be mixed with the gel catalyst by providing an extrusion roll in the combining apparatus.

In one embodiment, the step of combining the continuous fiber mat with the catalytic sol through the combining device means that the catalytic sol is sprayed (poured or painted) onto the continuously moving fiber mat in the combining device, and the step of combining the catalytic sol with the catalytic sol is performed by sufficiently stirring and mixing the sol without gel catalyst and the gel catalyst through a mixing and stirring tank to form the catalytic sol, and after sufficiently mixing, the catalytic sol is sprayed onto the fiber mat in the combining device for use, and sufficiently mixing is performed to perform uniform gel reaction.

In one embodiment, the step S1-2 of combining the sol and the gel catalyst without the gel catalyst by passing the continuous fiber mat through the combining apparatus means that the fiber mat is combined with the sol and the gel catalyst without the gel catalyst by spraying (or pouring or brushing) the sol and the gel catalyst without the gel catalyst, respectively, onto the continuously moving fiber mat in the combining apparatus, and the sol and the gel catalyst without the gel catalyst are mixed on the fiber mat to form the catalytic sol. By spraying (or pouring or brushing) onto the fiber mat respectively, the injection rate can be controlled by controlling the respective control device so as to prevent the viscosity from being increased before spraying (or pouring or brushing), which is beneficial to controlling the gel time and the physical properties of the aerogel; but separate spraying (or pouring, or brushing) may have a problem that the sol and the gel catalyst, which are combined with the fiber mat and do not contain the gel catalyst, are not sufficiently mixed, and the sol and the gel catalyst, which do not contain the gel catalyst, may be supplemented by providing squeeze rolls in the combining apparatus.

Further, the continuous fiber mat still can have the problem of insufficient combination after the sol is combined by combining equipment, an extrusion roller is arranged in the combining equipment or at one side of the combining equipment to extrude or calender the wet mat, so that the catalytic sol can more fully enter the inside of the fiber mat, the loss of the sol combined by the wet mat is reduced, the sol content in the wet mat is improved, the aerogel content in a final aerogel felt product is further improved, the heat insulation performance of the aerogel mat is improved, and the wet mat is more uniform in thickness due to the extrusion of the extrusion roller to the wet mat.

Further, the unreeling speed of the fibers in the step S1-2 is required to meet the requirement that the speed of the unfolded fiber mats passing through the bonding equipment is required to meet the requirement that the bonding time of the fiber mats to the sol is 0.1-10min.

Further, when the sol containing no gel catalyst and the gel catalyst are mixed in the mixing tank to form a catalytic sol before being injected into the combining device, and then injected into the combining device, the combination time of the fiber mat and the catalytic sol is preferably 0.1 to 1min.

In one embodiment, the method of making a gel-felt further comprises the steps of:

s3, rolling the gel felt into a coiled gel felt or cutting the gel felt into a sheet-shaped gel felt.

In one embodiment, the unreeling speed of unreeling the fiber mat in the step S1-2, the moving speed of the wet mat in the step S2, and the reeling speed of reeling the gel mat into the rolled gel mat in the step S3 are as follows: the winding speed is consistent with the unreeling speed and the moving speed, so that the continuous fiber felt is tensioned, and the fiber felt is prevented from being broken due to overlarge tensioning force in the moving process.

and S3', rolling the gel felt by a press roller before winding and rolling or cutting the gel felt into pieces.

Because the fiber mat can generate certain deformation under the action of gravity and traction force, the squeeze roller is arranged before rolling or cutting into slices for controlling the thickness uniformity, and the thickness tolerance of the gel product is reduced.

Further, the calendering depth is 0-40% of the original thickness of the wet felt.

The invention also provides a gel felt prepared by the method.

a) The gel felt is prepared by adopting the preparation method of the gel felt;

In one embodiment, the above "optionally" indicates that step b) may or may not be performed; the aerogel felt is obtained after the treatment of the steps a), b) and c); or alternatively, the aerogel blanket is obtained after the treatment of step a) and step c).

In one embodiment, the method of making the aerogel blanket further comprises the steps of:

d) The aerogel blanket obtained in step c) is modified, preferably by a gas phase modifier.

In one embodiment, the aging treatment may allow more Si-O-Si bonds and/or Al-O-Al bonds to form a wet gel (sol polycondensation gelation forms a gel, which is called wet gel because the gel is internally filled with a large amount of solvent at this time), and the gel network structure is more stably formed, facilitating the maintenance of the pore structure in the subsequent drying process, thereby improving the mechanical stability of the aerogel blanket. Aging the gelled wet gel in a suitable temperature range to reduce the microporous structure of the gel, enhance the optimal pore structure, and increase the permeability and mechanical properties of the gel. The aging treatment of the present invention is preferably carried out by immersing the gelled wet gel mat in a solvent and maintaining the wet gel mat at 30 to 70 ℃ for 1 to 10 hours. When the aging temperature is lower than 30 ℃, the aging time becomes longer, and when the aging temperature is higher than 70 ℃, the temperature exceeds the boiling point of ethanol, and evaporation causes solvent loss.

In one embodiment, the aging solvent comprises an alcoholic solvent and/or deionized water; preferably, the alcoholic solvent is ethanol.

In one embodiment, the modified gel product may be obtained after the modification treatment. The modification treatment is to put the gel to be modified into a modification solution for soaking treatment or to introduce a gas-phase modification reagent into the gel to be modified. The modification treatment may be performed before or after the drying, and after the modification treatment by immersing after the drying, the aerogel material after the modification treatment may be further subjected to secondary drying.

In one embodiment, the gas phase modifying agent is obtained by heating and evaporating the modifying agent.

In one embodiment, the modifying solution includes a modifying reagent, an alcohol solvent, and optionally a catalyst, with or without addition.

In one embodiment, the modifying agent is a hydrophilic modifying agent, a hydrophobic modifying agent, or a mixture of both.

In one embodiment, the hydrophilic modifying agent is a hydrophilic alkoxysilane of the formula R _1n Si(OR ₂ ) _(4-n) The method comprises the steps of carrying out a first treatment on the surface of the Wherein R is ₁ Is a hydrophilic group, R ₂ Is alkyl, n is the number of hydrophilic groups, 4-n is the number of alkyl groups, and n is an integer between 1 and 3. Specifically, the hydrophilic modification reagent comprises any one or more of 3-aminopropyl methyl dimethoxy silane, 3-aminopropyl methyl diethoxy silane, aminoethyl aminopropyl methyl diethoxy silane, diethylenetriamine propyl trimethoxy silane, gamma-aminopropyl triethoxy silane, gamma-piperazinyl propyl methyl dimethoxy silane, gamma-glycidol ether oxypropyl trimethoxy silane and gamma-N-N-butyl-gamma-aminopropyl trimethoxy silane.

In one embodiment, the hydrophobic modifying agent comprises any one or more of a hydrophobic alkoxysilane, hexamethyldisiloxane, and hexamethyldisilazane; the molecular formula of the alkoxy silane is R _3m Si(OR ₄ ) _(4-m) Wherein R is ₃ Is a hydrophobic group, R ₄ Is alkyl, m is the number of hydrophobic groups, 4-m is the number of alkyl, and the value of m is an integer between 1 and 3. Specifically, the hydrophobic modification reagent comprises any one of methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, propyltrimethoxysilane, chloropropyltriethoxysilane, chloropropyltrimethoxysilane, chloropropylmethyldimethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, trimethylchlorosilane, hexamethyldisiloxane and hexamethyldisilazaneOne or more.

In one embodiment, the alcohol solvent is any one or more of methanol, ethanol, propanol, isopropanol, ethylene glycol, propylene glycol, glycerol.

In one embodiment, the catalyst is a basic catalyst.

In one embodiment, the dried silica aerogel retains a low thermal conductivity immediately after drying, but has unreacted (Si-OR) and partially reacted (Si-OH) groups left after the end of the polymer reaction due to the side chains of some of the siloxanes of the silica aerogel. These groups are capable of contacting the water in the environment and, due to the exceptionally high specific surface area of the aerogel, there are more points of contact between the silica aerogel and the water in the environment, such that the silica aerogel gradually increases the thermal conductivity. Therefore, in order to maintain low thermal conductivity, silica aerogel is hydrophobically modified.

In one embodiment, the hydrophobicizing modification is carried out by reacting hydroxyl moieties on the gel, such as silanol groups (Si-OH) present on the silica gel backbone, with functional groups of the hydrophobicizing agent, the resulting reaction converting the silanol groups with the hydrophobicizing agent into hydrophobic groups on the silica gel backbone.

The surface modification is performed using an organosilane compound as a hydrophobizing agent, and the organosilane compound includes trimethylchlorosilane, hexamethyldisilazane, methyltrimethoxysilane, trimethylethoxysilane, ethyltriethoxysilane, phenyltriethoxysilane, and the like. The gel may be immersed in a mixture of a hydrophobizing agent and a hydrophobizing treatment solvent in which the hydrophobizing agent is soluble, and it may also be miscible with the gel solvent in the wet gel. The hydrophobe treatment solvent comprises one or more of methanol, ethanol, isopropanol, xylene, toluene, benzene, dimethylformamide. The hydrophobizing treatment process comprises mixing or stirring to help the hydrophobizing agent penetrate the wet gel, and the hydrophobizing treatment process also comprises changing other conditions such as temperature and pH value to further optimize the treatment result, and washing the wet gel to remove unreacted compounds and reaction byproducts after the reaction is completed. In the present invention, the organosilane compound and ethanol are preferably mixed in a molar ratio of 1: 2-1: 5, mixing to obtain a modified liquid, and immersing the wet gel felt in the modified liquid for modification. The modified product is washed 1-2 times to remove unreacted products and byproducts generated in the modification reaction process.

In one embodiment, the wet gel felt is subjected to solvent substitution for 1 to 3 times and then dried, and the solvent substitution uses a nonpolar organic solvent to replace alcohol and water in the pore structure of the wet gel felt. The nonpolar organic solvent is usually mixed by normal hexane and ethanol, the wet gel felt is placed into the mixed liquid for soaking and replacing for 4 to 6 hours, and the solvent replacement is repeated for 1 to 3 times.

In one embodiment, the drying process is by removing solvent within the pore structure of the gel while maintaining the pore structure of the gel, and drying the gel mat into an aerogel mat by the drying process.

In one embodiment, the drying treatment comprises supercritical drying (e.g., ethanol supercritical drying, CO ₂ Supercritical drying), atmospheric drying, and freeze drying. The drying temperature of the ethanol supercritical drying treatment is 245-260 ℃, the drying pressure is 8-11 MPa, the heating rate is 5-20 ℃/min, the supercritical state holding time is 0.5-3 h, and the air release time is 3-9 h; CO ₂ The drying temperature of the supercritical drying treatment is 40-55 ℃, the drying pressure is 8-20 MPa, the heating speed is 1-5 ℃/min, the replacement time is 3-12 h, and the deflation time is 3-12 h; the normal pressure drying treatment is to replace the normal alkane solvent for 6 to 24 hours and dry the mixture at the normal pressure for 6 to 24 hours at the temperature of 50 to 80 ℃; the freeze drying treatment is that the pre-freezing time is 3-12 h, the pre-freezing temperature is minus 30 ℃ to minus 5 ℃, the cold trap temperature is minus 60 ℃ to minus 40 ℃, the vacuum degree is 10-500 Pa, and the drying time is 12 h-36 h.

It should be noted that the steps of aging, modification and solvent replacement in the process of preparing the aerogel blanket are unnecessary, and can be selected according to the preparation process of the aerogel blanket and the product performance requirement of the aerogel blanket.

Further, before drying, the gelled roll is unwound and wound together with the diversion layer into a roll having more than one layer.

Further, the diversion layer is membranous or netlike.

In one embodiment, the prepared aerogel blanket has a more uniform density of the whole roll of aerogel blanket, the density variation of different positions in the whole roll of aerogel blanket is less than 15%, the heat insulation performance of the whole roll of aerogel blanket is more uniform, the heat insulation performance of different positions in the whole roll of aerogel blanket is less than 15%, the aerogel blanket has good surface appearance, and the reject ratio caused by crushing, pit, protrusion and fold conditions is less than 15%.

The present invention further provides an apparatus for preparing a gel-felt, the apparatus comprising:

a bonding device for bonding the sol and the fiber mat;

the gel felt rolling device or the clamping conveying device is positioned at the other side of the combining device and forms a length difference or a height difference with the combining device, the length difference or the height difference is sufficient to enable the sol-bonded fiber mat to gel during movement to form a gel mat;

the gel felt rolling device is used for rolling the gel felt into a rolled gel felt and providing traction force for the gel felt;

and the clamping and conveying device is used for clamping the gel felt and providing traction force for the gel felt.

In some embodiments, the apparatus further comprises a gel mat cutting apparatus disposed after the nip conveyor apparatus for cutting the gel mat nipped by the nip conveyor apparatus into sheet-like gel mats.

In the present invention, the term "height difference" refers to a difference in distance between the combining device and the gel felt winding device or the grip transfer device in the vertical direction; the term "length difference" refers to the difference in distance in the horizontal direction between the joining device and the gel felt take-up device or the gel felt cutting device.

In some embodiments, when the gel felt rolling device or the clamping conveying device is positioned at the other side of the combining device, the height difference formed between the gel felt rolling device or the clamping conveying device and the combining device is zero, and the length difference is not zero, namely the gel felt rolling device or the gel felt cutting device is horizontally arranged with the combining device.

In some embodiments, when the gel felt rolling device or the clamping conveying device is positioned at the other side of the combining device, the height difference formed between the gel felt rolling device or the clamping conveying device and the combining device is not zero, and the length difference is not zero, namely the gel felt rolling device or the gel felt cutting device and the combining device are arranged at any included angle along the horizontal direction.

In some embodiments, the fiber mat (wet mat) combined with the sol does not move and gel through the moving element with a solid interface, so that the conditions that the wet mat is contacted with the moving element, gel caused by gel on the moving element stays on the surface of the moving element (such as a conveyor belt) to form gel solid blocks (or powder), and the gel solid blocks adhered on the moving element further cause the gel mat moving on the moving element to have folds and pits, and the product quality of the gel mat is affected can be avoided.

In some embodiments, the apparatus for preparing a gel-felt comprises:

a bonding device for bonding the sol and the fiber mat;

a felt body supply device connected to one side of the bonding device, for continuously supplying the unwound fiber felt to the bonding device by unwinding the fiber coil felt;

The gel felt rolling device or the clamping conveying device is positioned at the other side of the combining device and forms a length difference with the combining device, and the length difference is required to be enough to enable the fiber felt combined with the sol to gel to form the gel felt in the moving process;

the gel felt rolling device is used for rolling the gel felt into a rolled gel felt, and provides traction for the gel felt;

In some embodiments, the apparatus for preparing a gel-felt comprises:

a bonding device for bonding the sol and the fiber mat;

the gel felt rolling device or the clamping conveying device is positioned at the other side of the combining device, and forms a height difference and a length difference with the combining device, wherein the height difference and the length difference are required to be satisfied so that the fiber felt combined with the sol can be gelled to form the gel felt in the moving process;

The beneficial effects of the technical scheme are that: the device does not comprise a moving element used for moving in the prior art, but utilizes the traction effect of the rolling device to enable the fiber felt to move along the horizontal direction or form any included angle with the horizontal direction, and the gel time is controlled to control the fiber felt combined with the sol to gel to form the gel felt in the moving process of the fiber felt combined with the sol along the horizontal direction or form any included angle with the horizontal direction under the traction effect of the rolling device, so that the quality influence of gel blocks formed by the gel on the aerogel felt products due to the gel retention moving element caused by the surface tension effect between the fiber felt combined with the sol and the moving element is avoided. And the loss of raw materials and the damage of gel blocks to production equipment in the processing process are reduced, so that the production cost and the process failure rate are reduced. The fiber felt with any included angle along the horizontal direction or with the horizontal direction can also provide bearing capacity for ungelatinized sol, so that the problems of poor uniformity of gel felt performance and the like caused by uneven gel distribution in the fiber felt due to downward flow of ungelatinized sol along the surface of the fiber felt under the action of gravity in the vertical movement process are avoided.

In some embodiments, the apparatus for preparing a gel-felt further comprises:

a gel catalyst injection device for injecting a gel catalyst into the bonding device so as to mix with the gel catalyst and bond with the fiber mat.

In some embodiments, the apparatus for preparing a gel-felt further comprises:

the mixing and stirring tank is used for fully mixing and stirring the sol without the gel catalyst and the gel catalyst to form catalytic sol;

and the stirring tank injection device is communicated with the mixing stirring tank and is used for injecting the catalytic sol in the mixing stirring tank into the combining device.

In some embodiments, the sol injection apparatus injects the sol without the gel catalyst into the mixing tank so that the sol without the gel catalyst is sufficiently mixed with the gel catalyst; gel catalyst injection apparatus injects a gel catalyst into a mixing tank so that the gel catalyst is well mixed with a sol containing no gel catalyst.

In some embodiments, to ensure adequate mixing of the sol free of gel catalyst with the gel catalyst, the prepared sol free of gel catalyst and the gel catalyst are mixed prior to injection into the bonding apparatus to obtain a catalytic sol, which is then injected into the bonding apparatus.

In some embodiments, the sol injection device, the gel catalyst injection device and the stirring tank injection device are respectively provided with flow control devices for controlling the flow of the sol without the gel catalyst, the flow of the gel catalyst and the flow of the catalytic sol respectively, so that the gel time is controlled.

In some embodiments, the combining device is provided with a feed inlet, and the sol injection device (capable of conveying sol) and the gel catalyst injection device (capable of conveying gel catalyst) are respectively connected with the feed inlet of the combining device to continuously inject the sol and the gel catalyst without the gel catalyst into the combining device.

In one embodiment, the sol injection device is connected to the first feed port, and the gel catalyst injection device is connected to the second feed port, where the first feed port and the second feed port may be disposed at the top end and the bottom end of the combining device, or may be disposed at two side ends of the combining device, or may be disposed at the top end, the bottom end, or the same side end of the combining device.

In one embodiment, the injection amount of the sol and the gel catalyst without the gel catalyst is required to keep the liquid level of the catalytic sol formed by mixing the sol and the gel catalyst without the gel catalyst in the combining device at a position slightly overflowed on the fiber mat so as to ensure that the fiber mat can be fully soaked.

In one embodiment, a spraying device is arranged in the combining device, the sol without gel catalyst and the gel catalyst are sprayed onto the fiber felt respectively, and the liquid level of the catalytic sol after the sol without gel catalyst and the gel catalyst in the combining device are mixed is kept at a position slightly overflowing on the fiber felt, so that the fiber felt can be fully impregnated.

In one embodiment, a pouring device is arranged in the combining device, sol without gel catalyst and gel catalyst are poured onto the fiber felt respectively, and the liquid level of the catalytic sol after the sol without gel catalyst and the gel catalyst are mixed in the combining device is kept at a position slightly overflowed on the fiber felt, so that the fiber felt can be fully impregnated.

In one embodiment, a brushing device is arranged in the combining device, the sol without gel catalyst and the gel catalyst are respectively brushed on the fiber mat, and the liquid level of the catalytic sol after the sol without gel catalyst and the gel catalyst in the combining device are mixed is kept at a position slightly overflowed on the fiber mat so as to ensure that the fiber mat can be fully impregnated.

In one embodiment, a feed port is provided in the combining device, and a stirred tank injection device (capable of delivering catalytic sol) is connected to the feed port of the combining device to continuously inject the catalytic sol into the combining device.

In one embodiment, the stirred tank injection device is disposed at the top or bottom end of the bonding device.

In one embodiment, the amount of catalyst sol injected is maintained in combination with the liquid level of catalyst sol in the apparatus at a location slightly above the fiber mat to ensure that the fiber mat is sufficiently impregnated.

In one embodiment, a spraying device is arranged in the combining device to spray the catalytic sol onto the fiber mat, and the liquid level of the catalytic sol in the combining device is kept at a position slightly overflowed on the fiber mat so as to ensure that the fiber mat can be fully impregnated.

In one embodiment, a pouring device is provided in the bonding device to pour the catalytic sol onto the fiber mat and to maintain the level of the catalytic sol in the bonding device in a slightly spilled position on the fiber mat to ensure adequate impregnation of the fiber mat.

In one embodiment, a brushing device is arranged in the combining device to brush the catalytic sol onto the fiber mat, and the liquid level of the catalytic sol in the combining device is kept at a position slightly overflowed on the fiber mat so as to ensure that the fiber mat can be fully impregnated.

In one embodiment, to facilitate storage and transport of the fiber mat, the fiber mat is typically a fiber mat formed by winding a fiber mat having a length of 15 to 200 meters in a wound form, and the fiber mat is supplied to the bonding apparatus by unwinding and unwinding the fiber mat continuously at a constant rate by a mat supply apparatus.

In one embodiment, to ensure adequate and uniform impregnation of the fiber mat, the bonding apparatus includes internally located squeeze rolls for impregnating the gel catalyst-free sol and gel catalyst or catalytic sol into the fiber mat to promote uniform impregnation of the gel catalyst-free sol and gel catalyst or catalytic sol into the fiber mat to ensure that the fiber mat is capable of saturated impregnation.

In one embodiment, the squeeze rolls in the bonding apparatus are provided with a drive apparatus for rotationally driving the fiber mat within the bonding apparatus.

In one embodiment, support mechanisms (such as carrier rollers) are respectively arranged at two side ends of the combination device so as to facilitate movement of the fiber mat into and out of the combination device, and the support mechanisms are arranged so as to facilitate movement of the fiber mat.

In one embodiment, the apparatus for preparing a gel-felt further comprises:

and the lifting mechanism is arranged on the other side of the combined equipment.

In one embodiment, the lift mechanism can be used to move the end of the fiber mat at a predetermined speed (e.g., downward drop or move in a horizontal direction or move in any angle to the horizontal), the predetermined moving speed is the same as the unreeling speed of the felt supply device, so that the operation can keep the fiber felt moving at a constant speed as a whole. The fiber mat end refers to the fiber mat section that comes off the fiber mat end of the mat supply device to the fiber mat between the fiber mats of the lifting mechanism when the fiber mat comes off the mat supply device at the end of unreeling.

In one embodiment, the lifting mechanism further comprises a clamping mechanism for clamping the fiber mat ends, wherein the clamping mechanism clamps and fixes the fiber mat ends so that the fiber mat can move at a constant speed along with the lifting mechanism.

In one embodiment, the lifting mechanism is a chain transmission type lifting platform, the tail end of the fiber mat combined with the catalytic sol after unreeling is arranged on the lifting mechanism, a worker uses the lifting mechanism to control the tail end of the fiber mat to move downwards at a preset speed, in the downward moving process, the catalytic sol combined with the tail end of the fiber mat is gelled into a gel mat, and when the lifting mechanism drives the gel mat to the height of the reeling device or the cutting device, the reeling device winds the gel mat or the cutting device cuts the gel mat into gel sheets.

In one embodiment, the apparatus for preparing a gel-felt further comprises:

and the bracket mechanism is arranged between the combining equipment and the gel felt rolling equipment or the gel felt cutting equipment.

In one embodiment, the support mechanism is a fixing device, and is not moved or rotated along with the gel felt or the fiber felt, and is only used for playing a supporting role, the contact area between gas and wet felt can be reduced by setting the support mechanism, more importantly, the length difference between the gel felt winding device or the gel felt cutting device and the combining device in the horizontal direction can be avoided to be too long by setting the support mechanism, and the fiber felt or the gel felt is broken due to too large tensioning force in the moving process caused by too heavy mass.

In some embodiments, the method of making the gel-felt is based on the apparatus for making a gel-felt described above.

The present invention will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the particular embodiments described herein are illustrative only and are not intended to limit the invention, i.e., the embodiments described are merely some, but not all, of the embodiments of the invention. The components of the embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the invention, as presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be made by a person skilled in the art without making any inventive effort, are intended to be within the scope of the present invention.

It should be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

The features and capabilities of the present invention are described in further detail below in connection with the examples.

Example 1

An apparatus for preparing a silica gel felt, as shown in fig. 2, comprising:

a bonding device 8 for bonding a silica sol catalyzed by a gel catalyst (i.e., a catalytic sol) to the fiber mat 6;

a felt supply device 5 connected to one side of the bonding device 8 for unreeling the fiber roll felt to supply the bonding device 8 with a continuous felt;

a mixing and stirring tank 4 for sufficiently mixing and stirring the silica sol and the gel catalyst to form a silica sol catalyzed by the gel catalyst, and injecting the silica sol catalyzed by the gel catalyst into the combining device 8;

a silica sol injection apparatus 1 for injecting a silica sol into a mixing tank 4 so as to sufficiently mix the silica sol with a gel catalyst;

a gel catalyst injection device 2 for injecting a gel catalyst into the mixing tank 4 so as to sufficiently mix the gel catalyst with the silica sol;

the silica sol injection device 1 and the gel catalyst injection device 2 are respectively provided with a flow control device 3 for controlling the flow rates of the silica sol and the gel catalyst;

The mixing and stirring tank 4 is communicated with the silica sol injection equipment 1 and the gel catalyst injection equipment 2, and is used for fully mixing and stirring the sol and the gel catalyst to form silica sol catalyzed by the gel catalyst;

a stirring tank injection device (not shown in the figure) which communicates with the mixing tank 4 and injects the catalytic sol in the mixing tank 4 into the joining device 8;

a gel felt winding device 10 and a combining device 8 form a level difference, wherein the level difference is required to enable the fiber felt 6 combined with the silica sol catalyzed by the gel catalyst to gel to form a gel felt in the moving process of utilizing the traction force of the winding device;

gel felt rolling device 10 is used for rolling the silica gel felt into a rolled silica gel felt.

Example 2

A silica gel felt was prepared by using the apparatus of example 1, specifically comprising:

1) Tetraethoxysilane is taken as a silicon dioxide precursor, tetraethoxysilane, ethanol and water are uniformly mixed, wherein the mol ratio of the tetraethoxysilane is as follows: ethanol: water = 1:3:6, preparing a base material; adding sulfuric acid, regulating the pH value to 4, and uniformly stirring to obtain silica sol; the gel catalyst is alkaline catalyst ammonia water; injecting the silica sol and the gel catalyst into a mixing and stirring tank 4 through a flow control device 3 respectively, wherein the flow ratio of the silica sol to the gel catalyst is such that the pH value of the sol after being fully mixed in the mixing tank is 8, and injecting the mixture into a combining device 8 from the top end of the combining device 8 after being fully mixed in the mixing and stirring tank 4;

2) Unreeling the glass fiber roll felt, supplying the continuously unreeled fiber felt 6 to a combining device 8 by a felt body supply device 5, soaking the continuous fiber felt 6 into silica sol catalyzed by a gel catalyst in the combining device 8 through the combining device 8 before the silica sol is gelled, combining the glass fiber felt 6 with the catalyzed sol, extruding the fiber felt 6 by an extruding roller 9 in the combining device 8, and promoting the catalyzed sol to be fully combined with the fiber felt 6;

3) The fiber felt 6 combined with the silica sol catalyzed by the gel catalyst moves along the horizontal direction under the action of traction force, and is gelled to form the silica gel felt in the process of the traction force action movement;

4) Rolling the silica gel felt into a rolled silica gel felt;

the unreeling speed of unreeling the fiber roll felt in the step 2), the moving speed of the fiber felt 6 combined with the silica sol catalyzed by the gel catalyst in the step 3) moving along the horizontal direction under the action of traction force, and the reeling speed of reeling the silica gel felt into the rolled silica gel felt in the step 4) are as follows: the winding speed is consistent with the unwinding speed and the moving speed, the speed is that the combination time of the silica sol catalyzed by the gel catalyst and the silica sol soaked in the combination equipment 8 of the fiber mat 6 is 1min, and the time of the fiber mat 6 in the horizontal moving process of the traction action is 10min, so that the fiber mat 6 is fully combined with the silica sol catalyzed by the gel catalyst, and the fiber mat is gelled in the horizontal moving process of the traction action.

Example 3

The present example provides a silica aerogel blanket.

As shown in FIG. 1, the silica gel felt obtained in example 2 was subjected to aging, hydrophobic modification, solvent substitution, and supercritical drying to obtain an aerogel felt having hydrophobicity, wherein the aging step was performed by subjecting the rolled gel felt to aging at 70℃for 1 hour, followed by surface modification with hexamethyldisilazane, subjecting the modified gel felt to solvent substitution for 3 times, and then subjecting the silica gel felt to supercritical drying in a supercritical drying apparatus, and replacing alcohol and water in the pore structure of the silica gel felt with CO ₂ After that discharge CO ₂ Obtaining the silica aerogel felt.

Example 4

This example provides an apparatus for preparing a silica gel felt, which differs from example 1 in that: as shown in fig. 3, the apparatus for preparing a silica gel felt is not provided with a mixing tank 4 and a tank injection apparatus;

a silica sol injecting device 1 for injecting a silica sol into the bonding device 8 so as to be mixed with a gel catalyst in the bonding device 8 with the silica sol to be bonded with the fiber mat 6 body;

A gel catalyst injection device 2 for injecting a gel catalyst into the bonding device 8 so as to be mixed with the silica sol and bonded with the fiber mat 6 body with the gel catalyst;

the gel felt winding device 10 is positioned at a low position and forms a level difference and a height difference with the combining device 8 positioned at a high position, wherein the level difference and the height difference are required to enable the fiber felt 6 combined with the silica sol catalyzed by the gel catalyst to gel to form the gel felt in the process of moving along the direction forming an included angle of 10 degrees with the horizontal direction by utilizing the traction force action and the gravity action of the winding device;

further comprising a traction mechanism 11 arranged on the other side of the joining device 8, said traction mechanism 11 being able to be used to move the front end of the fibre mat 6 to the winding device 10 at a predetermined speed; the lifting mechanism comprises a clamping mechanism (not shown in the figure) for clamping the front end of the fiber mat, the front end of the fiber mat is clamped and fixed, so that the fiber mat can move at a constant speed along with the traction mechanism, the traction mechanism 11 is in a chain transmission type, the front end of the fiber mat 6 combined with silica sol catalyzed by a gel catalyst after unreeling is arranged on the traction mechanism 11, the traction mechanism clamps and fixes the front end of the fiber mat combined with silica sol catalyzed by the gel catalyst, a worker uses the traction mechanism 11 to move the front end of the fiber mat 6 combined with silica sol catalyzed by the gel catalyst at a preset speed, during the moving process, the silica sol catalyzed by the gel catalyst on the front end of the fiber mat 6 is gelled into a gel mat, when the traction mechanism 11 drives the front end of the gel mat to the reeling device 10, the clamping mechanism of the front end of the fiber mat is opened, the worker places the gel mat on the reeling device 10 to reel the gel mat until the whole gel mat is reeled into a reel-like gel mat, and the traction mechanism 11 returns to the other side of the combining device 8.

Example 5

A silica gel felt was prepared using the apparatus of example 4, the preparation method comprising:

1) Injecting silica sol and gel catalyst into the combining device 8, respectively; the flow ratio of silica sol to gel catalyst is such that the sol pH after thorough mixing in the combining device 8 is 8;

the winding speed is consistent with the unwinding speed and the moving speed, the speed is 10min when the fiber mat 6 passes through the combination equipment 8 and is combined with sol, gel catalyst and catalytic sol, and the time of the fiber mat 6 in the moving process of the gravity action and the traction action is 20min, so that the fiber mat 6 is fully combined with the catalytic sol, and is gelled in the gravity moving process.

In the step 3), the traction mechanism 11 is used to move the front end of the fiber felt 6 combined with the catalytic sol passing through the combining device 8 to the gel felt rolling device 10 along an included angle of 10 degrees with the horizontal direction as shown in fig. 3 under the action of traction force, the front end of the fiber felt 6 is rolled by the gel felt rolling device 10, the traction speed is consistent with the unreeling speed of the fiber felt before dipping, and the influence of unstable traction speed and unstable traction force on the quality uniformity and qualification rate of the gel felt on the manual traction of the front end of the fiber felt 6 combined with the catalytic sol to the gel felt rolling device 10 is avoided.

Example 6

The present example provides a silica aerogel blanket.

As shown in FIG. 1, the silica gel felt obtained in example 5 was subjected to aging, hydrophobic modification, solvent substitution, and supercritical drying to obtain an aerogel felt having hydrophobicity, wherein the aging step was performed by subjecting the rolled gel felt to aging at 70℃for 1 hour, followed by surface modification with hexamethyldisilazane, subjecting the modified gel felt to solvent substitution for 3 times, and then subjecting the silica gel felt to supercritical drying in a supercritical drying apparatus, and replacing alcohol and water in the pore structure of the silica gel felt with CO ₂ After that discharge CO ₂ Obtaining the silica aerogel felt.

Example 7

This example provides an apparatus for preparing a silica gel felt, which differs from example 1 in that: as shown in fig. 4, the gel felt cutting device 12 is located at a high position and forms a length difference and a height difference with the combining device 8 located at a low position, and the length difference and the height difference are enough to enable the fiber felt 6 combined with the silica sol catalyzed by the gel catalyst to move in a direction forming an included angle of 45 degrees with the horizontal direction as shown in fig. 4 by using traction force and gravity action and gel during the movement to form a gel felt;

A gel felt cutting device 12 for cutting the silica gel felt into a sheet-like silica gel felt, i.e., a gel sheet 13.

The gel felt cutting device 12 is also provided with a clamping and conveying device at the side close to the combining device 8, and a length difference and a height difference are formed between the high-position combining device 8 and the low-position combining device 8 and are used for clamping the gel felt, providing traction force for the gel felt and providing the gel felt for the gel felt cutting device 12; the length difference and the height difference should be such that the fiber mat 6, to which the silica sol catalyzed by the gel catalyst is bonded, is moved in a direction at an angle of 45 ° to the horizontal as shown in fig. 4 by traction and gravity and gelled during the movement to form a gel mat.

The device further comprises a traction mechanism 11 arranged on the other side of the combining device 8, wherein the traction mechanism 11 can be used for moving the front end of the fiber felt 6 to a clamping and conveying device 15 at a preset speed, and the clamping and conveying device 15 clamps and conveys the gel felt to a gel felt cutting device 12; the traction mechanism 11 comprises a clamping mechanism (not shown in the figure) for clamping the front end of the fiber mat, the front end of the fiber mat is clamped and fixed to enable the fiber mat to move at a constant speed along with the traction mechanism, the traction mechanism 11 is in a chain transmission type, the front end of the fiber mat 6 combined with silica sol catalyzed by a gel catalyst after unreeling is arranged on the traction mechanism 11, the traction mechanism 11 clamps and fixes the front end of the fiber mat 6 combined with silica sol catalyzed by the gel catalyst, a worker uses the traction mechanism 11 to move the front end of the fiber mat 6 combined with silica sol catalyzed by the gel catalyst at a preset speed, during the moving process, the silica sol catalyzed by the gel catalyst on the front end of the fiber mat 6 is gelled into a gel mat, when the traction mechanism 11 drives the gel mat to the height of the clamping and conveying equipment, the clamping and conveying equipment conveys the gel mat to the cutting equipment 12, the cutting equipment 12 cuts the gel mat into a sheet-shaped gel mat, and the traction mechanism 11 returns to the position of the combining equipment 8 to be unreeled for the next fiber mat to pass through the combining equipment 8.

The fiber mat 6 combined with the silica sol catalyzed by the gel catalyst has the problems that the silica sol is not gelled or the initial viscosity of gelation is relatively low when leaving the combining device 8, so that the glue solution on the fiber mat is lost, the gel mat cutting device 12 is positioned at the high position, the combining device 8 is positioned at the low position, and the lost glue solution is favorable for flowing back into the combining device 8 along the fiber mat.

Example 8

A silica gel felt was prepared using the apparatus of example 7, the preparation method otherwise being the same as example 1, additionally comprising:

4) The silica gel felt is cut into sheet-like silica gel felt.

In the step 3), the traction mechanism 11 is used to move the front end of the fiber mat 6, which is combined with the silica sol catalyzed by the gel catalyst and passes through the combining device 8, to the clamping and conveying device along an included angle of 45 degrees with the horizontal direction as shown in fig. 4 under the action of traction force, after the traction mechanism 11 pulls the front end of the fiber mat 6 to the clamping and conveying device, the clamping and conveying device clamps and conveys the gel mat to the gel mat cutting device 12, and the traction mechanism 11 is restored to the combining device 8 to unwind the next roll of fiber mat to pass through the combining device 8.

Example 9

The present example provides a silica aerogel blanket.

As shown in FIG. 1, the silica gel felt obtained in example 8 was subjected to aging, hydrophobic modification, solvent substitution, and supercritical drying to obtain an aerogel felt having hydrophobicity, wherein the aging step was performed by subjecting the rolled gel felt to aging at 70℃for 1 hour, followed by surface modification with hexamethyldisilazane, subjecting the modified gel felt to solvent substitution for 3 times, and then subjecting the silica gel felt to supercritical drying in a supercritical drying apparatus, and replacing alcohol and water in the pore structure of the silica gel felt with CO ₂ After that discharge CO ₂ Obtaining the silica aerogel felt. The aerogel blanket is sheet-like.

Example 10

This example provides an apparatus for preparing a silica gel felt, which differs from example 4 in that: as shown in fig. 5, a spraying device 14 is arranged in the combining device 8, and sprays the silica sol and the gel catalyst onto the fiber mat 6 respectively, and keeps the liquid level of the silica sol catalyzed by the gel catalyst after the silica sol and the gel catalyst are mixed in the combining device 8 to slightly overflow on the fiber mat 6 so as to ensure that the fiber mat 6 can be fully impregnated. The squeeze rolls 9 are provided with a drive device (not shown in the figures) for rotating the squeeze rolls 9 to drive the movement of the fibre mat in the joining device 8. The lower gel felt winding device 10 and the upper combining device 8 form a level difference and a height difference, which are sufficient to enable the fiber felt 6 combined with the silica sol catalyzed by the gel catalyst to gel to form a gel felt during movement in a direction at an angle of 85 degrees to the horizontal direction as shown in fig. 5 by the traction force and the gravity action of the winding device.

Example 11

A silica gel mat was prepared by using the apparatus of example 10, the other same as example 5 except that in step 2) a glass fiber rolled mat was unwound, a continuously unwound fiber mat 6 was supplied to a bonding apparatus 8 by a mat body supply apparatus 5, the continuous fiber mat 6 was passed through the bonding apparatus 8, silica sol and gel catalyst were sprayed onto the fiber mat 6 by a spraying apparatus 14 in the bonding apparatus 8, the fiber mat 6 was pressed by a pressing roller 9 in the bonding apparatus 8, the fiber mat 6 was driven to move by the pressing roller 9 in the bonding apparatus 8, the fiber mat 6 was bonded with the catalyzed sol from one end of the bonding apparatus 8 toward the other end of the bonding apparatus 8, and the pressing roller 9 promoted sufficient bonding of the catalyzed sol with the fiber mat 6. The lower gel felt winding device 10 and the upper combining device 8 form a level difference and a height difference, which are sufficient to enable the fiber felt 6 combined with the silica sol catalyzed by the gel catalyst to gel to form a gel felt during movement in a direction at an angle of 85 degrees to the horizontal direction as shown in fig. 5 by the traction force and the gravity action of the winding device.

The winding speed is consistent with the unwinding speed and the moving speed, the speed is 0.5min when the fiber felt 6 passes through the combination equipment 8 and is combined with sol, gel catalyst and catalytic sol, and the time of the fiber felt 6 in the moving process of the gravity action and the traction action is 10min, so that the fiber felt 6 is fully combined with the catalytic sol, and the fiber felt is gelled in the gravity moving process.

Example 12

The present example provides a silica aerogel blanket.

As shown in FIG. 1, the silica gel felt obtained in example 11 was subjected to aging, hydrophobic modification, solvent substitution, and supercritical drying to obtain an aerogel felt having hydrophobicity, wherein the aging step was performed by subjecting the rolled gel felt to aging at 70℃for 1 hour, followed by surface modification with hexamethyldisilazane, subjecting the modified gel felt to solvent substitution for 3 times, and then subjecting the silica gel felt to supercritical drying in a supercritical drying apparatus, and replacing alcohol and water in the pore structure of the silica gel felt with CO ₂ After that discharge CO ₂ Obtaining the silica aerogel felt.

Example 13

This example provides an apparatus for preparing a silica gel felt, which differs from example 1 in that: as shown in fig. 6, the spraying device 14 is arranged in the combining device 8, the silica sol catalyzed by the gel catalyst is conveyed to the spraying device 14 through the stirring tank injecting device to be sprayed on the fiber mat 6, and the liquid level of the silica sol catalyzed by the gel catalyst in the combining device 8 is kept to be slightly overflowed on the fiber mat 6, so that the fiber mat 6 can be fully impregnated. The other side of the combination device 8 is also provided with a squeeze roll 9 consisting of double rolls, the fiber felt is combined with the silica sol catalyzed by the gel catalyst through the combination device 8, and the silica sol catalyzed by the gel catalyst is more fully immersed into the fiber felt through the squeezing of the squeeze roll, the loss of the sol of the wet felt is reduced, the sol content in the wet felt is increased, the aerogel content in a final aerogel felt product is increased, and the heat insulation performance of the aerogel felt is improved; and the extrusion roller extrudes the wet felt so that the thickness of the wet felt is more uniform.

A support mechanism 16 is also provided between the joining device 8 and the gel felt take-up device 10 for providing support to the wet felt or gel felt.

Example 14

A silica gel mat was prepared using the apparatus of example 13, the method differing from example 2 in that step 2) unreels a glass fiber roll mat, continuously unreeled fiber mat 6 was supplied to a joining apparatus 8 by a mat body supply apparatus 5, continuous fiber mat 6 was passed through joining apparatus 8, silica sol catalyzed by a gel catalyst was sprayed onto fiber mat 6 by spraying apparatus 14 in joining apparatus 8, fiber mat 6 was extruded by extrusion roll 9 on one side of joining apparatus 8, glass fiber mat 6 was joined with catalyzed sol, extrusion roll 9 promoted sufficient joining of catalyzed sol with fiber mat 6, and wet mat thickness uniformity was controlled.

In the step 3), the traction mechanism 11 is used to move the front end of the fiber felt 6 combined with the catalytic sol passing through the combining device 8 to the gel felt rolling device 10 along the horizontal direction as shown in fig. 3 under the action of traction force, the front end of the fiber felt 6 is rolled by the gel felt rolling device 10, the traction speed is consistent with the unreeling speed of the fiber felt before dipping, and the influence of unstable traction speed and unstable traction force on the quality uniformity and qualification rate of the gel felt caused by manually dragging the front end of the fiber felt 6 combined with the catalytic sol to the gel felt rolling device 10 is avoided.

Example 15

The present example provides a silica aerogel blanket.

As shown in FIG. 1, the silica gel felt obtained in example 14 was subjected to aging, hydrophobic modification, solvent substitution, and supercritical drying to obtain an aerogel felt having hydrophobicity, wherein the aging step was performed by subjecting the rolled gel felt to aging at 70℃for 1 hour, followed by surface modification with hexamethyldisilazane, subjecting the modified gel felt to solvent substitution for 3 times, and then subjecting the silica gel felt to supercritical drying in a supercritical drying apparatus, and replacing alcohol and water in the pore structure of the silica gel felt with CO ₂ After that discharge CO ₂ Obtaining the silica aerogel felt. Example 16

This example provides an apparatus for preparing a silica gel felt, which differs from example 1 in that: as shown in fig. 7, the extruding roller 9 consisting of two rollers is further arranged in front of the gel felt rolling device 10, and is used for controlling the thickness uniformity of the gel felt, reducing the thickness tolerance of the gel felt and further controlling the thickness uniformity of aerogel felt products.

Example 17

A silica gel felt was prepared using the apparatus of example 16, the preparation method differing from example 2 in that: and step 4), calendering the gel felt by using a squeeze roller, and rolling the calendered silica gel felt into a rolled silica gel felt.

Example 18

The present example provides a silica aerogel blanket.

As shown in FIG. 1, the silica gel felt obtained in example 17 was subjected to aging, hydrophobic modification, solvent substitution, and supercritical drying to obtain an aerogel felt having hydrophobicity, wherein the aging step was performed by subjecting the rolled gel felt to aging at 70℃for 1 hour, followed by surface modification with hexamethyldisilazane, subjecting the modified gel felt to solvent substitution for 3 times, and then subjecting the silica gel felt to supercritical drying in a supercritical drying apparatus, and replacing alcohol and water in the pore structure of the silica gel felt with CO ₂ After that discharge CO ₂ Obtaining the silica aerogel felt.

Example 19

This example provides an apparatus for preparing a silica gel felt, which differs from example 1 in that: as shown in fig. 8, one side of the combining device 8 is further provided with a squeeze roll 9 composed of two rolls, after the fiber mat is combined with the silica sol catalyzed by the gel catalyst through the combining device 8, the silica sol catalyzed by the gel catalyst is more fully immersed into the fiber mat through the squeezing of the squeeze roll, so that the loss of the wet mat sol is reduced, the sol content in the wet mat is improved, the aerogel content in a final aerogel felt product is further improved, and the heat insulation performance of the aerogel mat is improved; and the extrusion roller extrudes the wet felt so that the thickness of the wet felt is more uniform.

The extrusion roller 9 consisting of double rollers is further arranged in front of the gel felt rolling device 10, and is used for rolling the gel felt before rolling and controlling the thickness uniformity of the gel felt, reducing the thickness tolerance of the gel felt and further controlling the thickness uniformity of aerogel felt products.

Example 20

A silica gel felt was prepared using the apparatus of example 19, the preparation method differing from example 2 in that: and step 2) is preceded by extruding the wet felt by using an extruding roller, so that the silica sol catalyzed by the gel catalyst is more fully immersed into the fiber felt, the loss of the wet felt sol is reduced, the sol content in the wet felt is improved, and the aerogel content in a final aerogel felt product is further improved.

And step 4), calendering the gel felt by using a squeeze roller, and rolling the calendered silica gel felt into a rolled silica gel felt.

Example 21

The present example provides a silica aerogel blanket.

As shown in FIG. 1, the silica gel felt obtained in example 20 was subjected to aging, hydrophobic modification, solvent substitution, and supercritical drying to obtain an aerogel felt having hydrophobicity, wherein the aging step was performed by subjecting the rolled gel felt to aging at 70℃for 1 hour, then surface-modifying with hexamethyldisilazane, subjecting the modified gel felt to solvent substitution for 3 times, then subjecting the silica gel felt to supercritical drying in a supercritical drying apparatus, and replacing alcohol and water in the pore structure of the silica gel felt with CO ₂ After that discharge CO ₂ Obtaining the silica aerogel felt.

Comparative example 1

The aerogel film blanket was produced using the method of example 1 of the prior art, such as patent CN 100540257C.

Comparative example 2

The aerogel film blanket was produced using the method of example 1 of the prior art, such as patent CN114541059 a.

And (3) testing:

the aerogel mats obtained in examples 3, 6, 9, 12, 15, 18, 21 and comparative examples 1 and 2 were subjected to sampling test, specifically, 3 different samples, namely, 9 samples each were taken for each of the front end, middle end and rear end of the wound whole roll of the aerogel mats of examples 3, 6, 12, 15, 18, 21 and comparative examples 1 and 2. The aerogel sheet felt of example 9 was obtained by selecting an aerogel sheet felt after cutting the front end, the middle end and the rear end of the whole roll of fiber felt, respectively taking 3 different samples, namely 9 samples for each roll of fiber felt, and testing the samples.

Density units are recorded as kg/m ³ The test method was performed using a method known in the art, the density of the aerogel blanket was measured by the standard test method GB/T5480-2008, and then a density average value and a density change rate were calculated from the densities of 9 samples recorded by the test, the density change rate being calculated as (density-density average value)/density average value, and only the density average value and the maximum value of the density change rate were shown in the following test data table.

The thickness unit was recorded in mm, the test method was performed using a method known in the art, the density of the aerogel blanket was measured by the standard test method BG/T34336-2017, then the thickness average value and the thickness change rate were calculated from the thicknesses of the 9 samples recorded by the test, the thickness change rate was calculated as (thickness-thickness average value)/thickness average value, and only the thickness average value and the thickness change rate maximum value were shown in the following test data table.

The thermal conductivity unit was recorded as W/(m·k), the test method was performed using methods known in the art, the thermal conductivity of the aerogel blanket at 25 ℃ was measured by standard test method GB/T10295-2008, and then the thermal conductivity average value and the thermal conductivity change rate were calculated from the thermal conductivities of the 9 samples recorded by the test, the thermal conductivity change rate being calculated as (thermal conductivity-thermal conductivity average value)/thermal conductivity average value, and only the thermal conductivity average value and the thermal conductivity change rate maximum value were shown in the following test data tables.

The compression ratio unit is recorded as a unit, the test method is carried out by adopting a method known in the art, and the compression ratio test method of the aerogel blanket is as follows: 1. original thickness d of test specimen ₀ The method comprises the steps of carrying out a first treatment on the surface of the 2. The thickness variation value under the pressure of 2MPa is measured by adopting a three-Si universal tester and an extension machine and is counted as delta ₂ (thickness under 2MPa pressure-original thickness), wherein the maximum force of the universal tester is 6000N, and the compression speed is 2mm/min; the calculated compression ratio is: Δd=δ ₂ /d ₀ *100%, and then a compression rate average value and a compression rate change rate were calculated from the compression rates of the 9 samples recorded by the test, the compression rate change rate being calculated as (compression rate-compression rate average value)/compression rate average value, and only the compression rate average value and the compression rate average value change rate maximum value were shown in the following test data table.

The unit of the defective rate of the appearance is recorded as the defective rate of the appearance, the test method is to test all aerogel film felts produced by using the whole roll of aerogel felts or the whole roll of fiber felts correspondingly, and the appearance defective rate of the aerogel film felts is determined as the defective appearance of the area of the partial area of the aerogel film felts, namely the area of the defective appearance area/the total area of the whole roll of aerogel film felts; the appearance defect rate of the aerogel sheet felt was determined as the appearance defect of the sheet felt when the aerogel sheet felt was wrinkled or dented or protruded or broken, and the appearance defect rate of the whole-roll aerogel sheet felt or the whole-roll fiber felt corresponding to the aerogel sheet felt of each example or comparative example is shown in the following test data table as the number of sheets of the appearance defect aerogel sheet felt/the total number of sheets of the whole-roll fiber felt corresponding to the aerogel sheet felt.

Table 1 test data for aerogel blankets made by the examples and comparative examples

The above description is only a preferred embodiment of the present invention, and the patent protection scope of the present invention is defined by the claims, and all equivalent structural changes made by the specification and the drawings of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing a gel felt, in particular to a continuous preparation method of the gel felt, which comprises the following steps:

s1, combining a fiber felt with sol to obtain a wet felt;

2. The method for preparing a gel felt according to claim 1, wherein in step S1, the method comprises the steps of:

s1-1, preparing a combination device containing sol;

3. The method for preparing a gel felt according to claim 1, wherein the step S2 specifically comprises the steps of:

4. The method for producing a gel felt according to claim 2, wherein in step S1-2: the combination comprises that continuous fiber mats are combined with sol through combination equipment in a pouring, brushing, soaking or spraying mode;

preferably, in step S1-2: the wet felt is extruded or calendered by arranging an extrusion roller in the combining equipment or at one side of the combining equipment.

Preferably, the unwinding speed of the fibers in the step S1-2 is enough that the speed of the unwound fiber mat passing through the combining device is enough that the combination time of the fiber mat and the sol containing no gel catalyst or the catalytic sol is 0.1-10min.

5. The method for producing a gel-mat according to claim 1 or 3, wherein in step S2, the contact area between the gas and the wet mat is 90% to 100%;

preferably, in step S2, the gas is air, preferably air at 20-35 ℃;

Preferably, in step S2, the gas-wet felt interface may be subjected to irradiation heating during the movement;

preferably, in step S2, the wet mat is subjected to a calendering treatment;

preferably, in step S2, the gel felt is subjected to a calendering treatment.

6. A gel-mat made using the method of any one of claims 1-4.

7. A method of making an aerogel blanket, the method comprising the steps of:

a) Preparing a gel felt using the method for preparing a gel felt according to any one of claims 1 to 5;

c) And c) drying the gel felt obtained in the step a) to obtain the aerogel felt.

Preferably, the method comprises the steps of:

8. An aerogel blanket prepared by the method of preparing an aerogel blanket of claim 7.

9. An apparatus for preparing a gel-felt, the apparatus comprising:

a bonding device for bonding the sol and the fiber mat;

the gel felt rolling device or the clamping conveying device is positioned at the other side of the combining device and forms a length difference or a height difference with the combining device, and the length difference or the height difference is required to enable the fiber felt combined with the sol to gel in the moving process to form the gel felt;

10. The apparatus of claim 9, wherein the apparatus for preparing a gel-felt further comprises:

gel catalyst injection means for injecting a gel catalyst into the bonding means so as to be mixed with the sol and bonded with the fiber mat with the gel catalyst;

preferably, the apparatus for preparing a gel felt further comprises:

the mixing and stirring tank is used for fully mixing and stirring the sol and the gel catalyst to form catalytic sol;