CN111333900A - Aramid nanofiber aerogel and preparation method thereof - Google Patents
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Abstract
The invention relates to an aramid nano-fiber aerogel and a preparation method thereof, wherein the method comprises the following steps of 1, preparing aramid fibers into an aramid nano-fiber dispersion liquid by using solid A, deionized water and dimethyl sulfoxide, uniformly mixing the aramid nano-fiber dispersion liquid and the deionized water according to the volume ratio of 1 (3-4) to obtain a mixed system A, and finally filtering the mixed system A to obtain the aramid nano-fiber gel; and 2, sequentially freezing, vacuum drying and normal-pressure drying the aramid nano-fiber gel to obtain the aramid nano-fiber aerogel. According to the invention, the growth of ice nuclei and the size of ice crystals can be adjusted through the filtering time and the freezing rate, and the pores in the aramid nanofiber aerogel are adjusted, so that the preparation of the aramid nanofiber aerogel with different pore sizes becomes possible, and reference is provided for the preparation of porous materials in the fields of chemical adsorption, special filtering, space loading, energy storage and the like.
Description
Technical Field
The invention belongs to the cross field of preparation technologies of porous materials and functional materials, and particularly relates to an aramid nanofiber aerogel and a preparation method thereof.
Background
Aerogel, also known as xerogel, solid air or solid smoke, refers to a substance whose space network structure is filled with gas and solid in appearance when most of the solvent is removed from the gel. Leading studies have shown that the fine structure design and proper selection of materials can allow the aerogel material to reach and air density (1.29 kg/m)3) The same is true. Therefore, the inventor proposes that the aerogel is a new state of matter, namely a fourth state of matter with density between solid and gas, and the aerogel has extremely wide application and development prospects. In 1931, aerogel exploration work began in the world at the earliest time, but limited to technical and knowledge limitations, most research stayed on silicon alcogels. With the maturity of nano materials and supercritical carbon dioxide drying technology, the aerogel and related researches renewedly develop new vitality, the attraction force is continuously increased in the aspects of low heat conductivity coefficient, large specific surface area, good noise elimination and controllable density materials, and the aerogel is widely researched in the fields of chemical adsorption, special filtration, space load catalysis, energy storage and the like according to the properties of light weight, large specific surface area and the like.
In the aspect of aerogel raw materials, compared with the characteristics of large density, weak crosslinking effect and the like of inorganic materials, the organic materials can be subjected to molecular design and bonding crosslinking, gradually enter the visual field and show advantages. Besides the green organic raw materials obtained from the nature such as cellulose, chitin and the like, artificially synthesized polyimide, aramid fiber and the like are good choices for preparing the aerogel. 2011 researchers put forward that para-aramid fiber is chemically cracked through potassium hydroxide/dimethyl sulfoxide to prepare aramid nano fiber, and a new direction for applying the aramid fiber is opened up. Based on aramid fiber nanocrystallization work, the preparation of aerogels with different pore sizes is realized through structural design and parameter regulation, and the method is very critical to the application in the fields of chemical adsorption, special filtration, space loading, energy storage and the like.
In conclusion, the preparation of the aramid nano-fiber aerogel with different pore sizes has important application, but no relevant report exists at present.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides the aramid nano-fiber aerogel and the preparation method thereof, and the aramid nano-fiber aerogel with controllable pore size and excellent compressibility is obtained.
The invention is realized by the following technical scheme:
a preparation method of aramid nanofiber aerogel comprises the following steps,
step 1, firstly, preparing aramid fibers into an aramid nanofiber dispersion liquid by using solid A, deionized water and dimethyl sulfoxide, wherein the solid A is potassium hydroxide, sodium hydroxide or potassium tert-butoxide, then uniformly mixing the aramid nanofiber dispersion liquid and the deionized water according to the volume ratio of 1 (3-4) to obtain a mixed system A, and finally filtering the mixed system A to obtain aramid nanofiber gel;
the aramid nano-fiber dispersion liquid is obtained by the following steps,
step 1a, mixing a solid A and deionized water to obtain a solution A;
step 1b, according to 1: adding dimethyl sulfoxide into the solution A according to the volume ratio of 50 to obtain a mixed system a;
step 1c, according to (1-5) g: adding aramid fibers into the mixed system a according to the proportion of 510ml, and uniformly mixing to obtain an aramid nanofiber dispersion liquid;
and 2, sequentially freezing, vacuum drying and normal-pressure drying the aramid nano-fiber gel to obtain the aramid nano-fiber aerogel.
Preferably, the step 2 is to add a mixed system of tert-butyl alcohol and deionized water into the aramid nano-fiber gel, and then to freeze the aramid nano-fiber gel after filtration.
Further, the filtering in the step 1 and the step 2 is carried out in a mode of filtering for 12-24 hours by using a filter screen.
And further, in the step 2, the volume ratio of the tert-butyl alcohol to the aramid nanofiber dispersion liquid is less than (20: 510).
Preferably, in the step 1, the aramid nano-fiber dispersion liquid and deionized water are stirred for 1-3 hours to obtain a mixed system A.
Preferably, in the step 2, the freezing temperature is-196 to-5 ℃, and the freezing time is 0.5 to 24 hours;
the vacuum drying temperature is-56 ℃, the air pressure is 12-18 Pa, and the time is 72-96 h.
Preferably, in the step 2, the temperature of the normal pressure drying is 95-105 ℃, and the time is 2-4 hours.
Preferably, in the step 1a, the mixing ratio of the solid A and the deionized water is (1-5) g: 10 ml.
Preferably, the aramid fiber is para-aramid fiber, and the form of the para-aramid fiber is chopped, filament, precipitation or pulp.
The aramid nanofiber aerogel prepared by the preparation method of the aramid nanofiber aerogel.
Compared with the prior art, the invention has the following beneficial technical effects:
the invention relates to a preparation method of aramid nano-fiber aerogel, which comprises the steps of uniformly mixing aramid nano-fiber dispersion liquid with deionized water, filtering to obtain aramid nano-fiber aerogel, preparing the aramid nano-fiber aerogel by adopting an ice template method, sequentially freezing and vacuum drying, regulating and controlling pores in the aramid nano-fiber aerogel by regulating ice nucleus growth and ice crystal size through filtering time and freezing rate, enabling the preparation of the aramid nano-fiber aerogel with different pore sizes to be possible, enabling the aramid nano-fiber aerogel to have better compressibility by relying on specific hydrogen bonds and physical interlacing among the aramid nano-fibers, realizing the crosslinking inside the aerogel through the hydrogen bonds among fiber molecule amide groups, skillfully utilizing the specific structure of the aramid nano-fiber chemical molecules, and providing reference for the preparation of porous materials in the fields of chemical adsorption, special filtering, space loading, energy storage and the like, provides reference for green chemical production. The preparation method of the invention has no extra impurity drug introduction, not only has stronger industrial production convenience, but also has almost no damage to the original performance of the aramid nano-fiber.
Furthermore, a mixed system of tert-butyl alcohol and deionized water is added into the aramid nano-fiber gel, the tert-butyl alcohol is uniformly dispersed in the aramid nano-fiber gel under the action of the deionized water, the pores of the gel are reduced by utilizing the freezing point of the tert-butyl alcohol, and the use amount of the tert-butyl alcohol can be used for further regulating and controlling the pores in the aramid nano-fiber aerogel.
Drawings
Fig. 1 is a diagram of an aerogel with a proportion of aramid fiber of 0.5% in the gel prepared in example 1 of the present invention.
Fig. 2 is an SEM image of 0.5% aramid aerogel in the gel prepared in example 1 of the present invention.
Fig. 3 is a physical diagram of an aramid nanofiber gel with the aramid fiber content of 1% prepared in example 2 of the present invention.
Fig. 4 is a diagram of an aerogel with the aramid fiber content of 1.0% in the gel prepared in example 2 of the present invention.
Fig. 5 is an SEM image of 1.0% aramid aerogel in the gel prepared in example 2 of the present invention.
Fig. 6 is a diagram of an embodiment of the tert-butyl alcohol-assisted frozen aerogel prepared in example 3 of the present invention.
Fig. 7 is an SEM image of tert-butanol assisted frozen aerogel prepared in example 3 of the present invention.
FIG. 8 is a schematic view of a freezer (-56 ℃) frozen aerogel prepared in example 4 of the present invention.
FIG. 9 is an SEM image of a freezer (-56 ℃) frozen aerogel prepared by example 4 of the present invention.
FIG. 10 is a schematic representation of a liquid nitrogen (-196 ℃) frozen aerogel prepared according to example 5 of the present invention.
FIG. 11 is an SEM image of liquid nitrogen (-196 ℃) frozen aerogel prepared in example 5 of the present invention.
Detailed Description
The present invention will now be described in further detail with reference to specific examples, which are intended to be illustrative, but not limiting, of the invention.
The invention relates to a preparation method of an aramid nanofiber aerogel, which comprises the following steps:
step 1, preparing an aramid nano-fiber dispersion liquid by using a system consisting of aramid fibers, dimethyl sulfoxide, water and alkali;
the aramid nano-fiber dispersion liquid is obtained by chemical cracking and is prepared by the following steps:
step 1a, according to (1-5) g: 10ml of potassium hydroxide, sodium hydroxide or potassium tert-butoxide was added to deionized water to give solution A.
Step 1b, according to 1: 50 volume ratio, adding dimethyl sulfoxide into the solution A to obtain a mixed system a.
Step 1c, according to (1-5) g: and (3) adding aramid fibers into the mixed system a according to a proportion of 510ml, and continuously performing magnetic stirring at room temperature to obtain a dark red dispersion liquid C, namely an aramid nanofiber dispersion liquid, wherein the aramid nanofibers can use aramid fiber product scraps as raw materials, the aramid fibers are para-aramid fibers, and the para-aramid fibers are chopped, long filaments, precipitated or pulp.
Step 2, preparing aramid nano-fiber gel;
the aramid nanofiber gel is obtained by the following steps:
and 2a, mixing the aramid nano-fiber dispersion liquid and deionized water according to the volume ratio of 1 (3-4), and magnetically stirring for 1-3 h for washing to obtain a mixed system A.
And 2b, standing and filtering the mixed system A on a 2800-mesh filter screen for 12-24 hours, controlling the filtering time to regulate the proportion of the gel aramid nanofiber and water, and removing residual potassium hydroxide, sodium hydroxide or potassium tert-butoxide and dimethyl sulfoxide to obtain the aramid nanofiber gel.
And 2c, replacing the deionized water with the same volume in the step 2a with a mixed system of the deionized water and the tertiary butanol, wherein the mixed system contains no more than 20ml of the tertiary butanol, the mixed system can uniformly disperse the tertiary butanol without transition stirring, and then repeating the step 2a and the step 2 b.
And 3, preparing the aramid nanofiber aerogel.
And 3a, respectively freezing the prepared aramid nano-fiber in the environments of a refrigerator (from minus 5 ℃ to minus 10 ℃), a vacuum freeze dryer (from minus 50 ℃ to minus 56 ℃) and liquid nitrogen (from minus 190 ℃ to minus 196 ℃), wherein the freezing time is 0.5-24 h.
And 3b, putting the frozen sample into a vacuum freeze dryer, and drying for 72-96 h at the temperature of-56 ℃ of a cold trap and under the air pressure of 12-18 Pa.
And 3c, drying the dried sample at the temperature of 95-105 ℃ for 2-4 h under normal pressure.
The gel washing and preparation technology focuses on utilizing the gravity and the natural acting force of the fluid, and the process is environment-friendly, stable and strong in operability.
Example 1
A preparation method of an aramid nanofiber aerogel comprises the following steps:
step 1, adding 2g of potassium hydroxide into 10ml of deionized water to obtain a solution A in which the potassium hydroxide is completely dissolved, adding 500ml of dimethyl sulfoxide into the solution A to obtain a mixed system B, adding 1g of para-aramid fiber in a form of short cut into the mixed system B, and continuously performing magnetic stirring at 25 ℃ for 24 hours to obtain a dark red dispersion liquid C, namely the aramid nanofiber dispersion liquid.
And 2, mixing and stirring the aramid nano-fiber dispersion liquid and deionized water according to the volume ratio of 1:3 for 3 hours, washing to obtain a mixed system D, filtering the mixed system D on a 2800-mesh filter screen for 12 hours to remove residual potassium hydroxide and dimethyl sulfoxide, and obtaining gel with the aramid nano-fiber accounting ratio of about 0.5%.
And 3, freezing the prepared aramid nano-fiber gel for 24 hours in a vacuum freeze dryer (-56 ℃), drying the frozen sample for 72 hours at the cold trap temperature of-56 ℃ and under the air pressure of 15Pa, taking out the sample, and drying the taken sample for 4 hours at the normal pressure and the temperature of 105 ℃ to remove water molecules which are not completely dried.
Example 2
A preparation method of an aramid nanofiber aerogel comprises the following steps:
step 1, adding 5g of potassium hydroxide into 10ml of deionized water to obtain a solution A in which the potassium hydroxide is completely dissolved, adding 500ml of dimethyl sulfoxide into the solution A to obtain a mixed system B, adding 1g of para-aramid fibers in the form of filaments into the mixed system B, and continuously magnetically stirring at 25 ℃ for 24 hours to obtain a dark red dispersion liquid C, namely the aramid nanofiber dispersion liquid.
And 2, mixing and stirring the aramid nano-fiber dispersion liquid and deionized water according to the volume ratio of 1:4 for 4 hours, washing to obtain a mixed system D, filtering the mixed system D on a 2800-mesh filter screen for 24 hours to remove residual potassium hydroxide and dimethyl sulfoxide, and obtaining gel with the aramid nano-fiber accounting ratio of about 1.0%.
And 3, freezing the prepared aramid nano-fiber gel for 24 hours in a vacuum freeze dryer (-56 ℃), drying the frozen sample for 80 hours at the cold trap temperature of-56 ℃ and under the air pressure of 17Pa, taking out the sample, and drying the taken sample for 4 hours at the normal pressure and the temperature of 105 ℃ to remove water molecules which are not completely dried.
Example 3
A preparation method of an aramid nanofiber aerogel comprises the following steps:
step 1, adding 3g of potassium hydroxide into 10ml of deionized water to obtain a solution A in which the potassium hydroxide is completely dissolved, adding 500ml of dimethyl sulfoxide into the solution A to obtain a mixed system B, adding 1g of para-aramid fiber in a form of short cut into the mixed system B, and continuously performing magnetic stirring at 25 ℃ for 24 hours to obtain a dark red dispersion liquid C, namely the aramid nanofiber dispersion liquid.
And 2, mixing and stirring the aramid nano-fiber dispersion liquid and deionized water according to the volume ratio of 1:4 for 3 hours, washing to obtain a mixed system D, filtering the mixed system D on a 2800-mesh filter screen for 24 hours to remove residual potassium hydroxide and dimethyl sulfoxide, and obtaining gel with the aramid nano-fiber accounting for about 1.0%.
And 3, freezing the prepared aramid nano-fiber gel for 24 hours in a refrigerator (-5 ℃) environment, putting the frozen sample into a vacuum freeze dryer, drying for 96 hours at the cold trap temperature of-56 ℃ and the air pressure of 15Pa, and drying the dried sample for 4 hours at the normal pressure and the 95 ℃.
Example 4
A preparation method of an aramid nanofiber aerogel comprises the following steps:
step 1, adding 2g of potassium hydroxide into 10ml of deionized water to obtain a solution A in which the potassium hydroxide is completely dissolved, adding 500ml of dimethyl sulfoxide into the solution A to obtain a mixed system B, adding 1g of para-aramid fiber in a form of short cut into the mixed system B, and continuously performing magnetic stirring at 25 ℃ for 24 hours to obtain a dark red dispersion liquid C, namely the aramid nanofiber dispersion liquid.
Step 2, mixing and stirring the aramid nano-fiber dispersion liquid and deionized water according to the volume ratio of 1:3 for 3 hours, washing to obtain a mixed system D, filtering the mixed system D on a 2800-mesh filter screen for 24 hours to remove residual potassium hydroxide and dimethyl sulfoxide, and obtaining gel with the aramid nano-fiber accounting for about 1.0%;
the deionized water is replaced by a mixed system of the deionized water and the tertiary butanol with the same volume, the system contains 20ml of the tertiary butanol, and the steps are repeated.
And 3, freezing the prepared aramid nano-fiber in a vacuum freeze dryer (-56 ℃) environment for 8 hours, putting the frozen sample into the vacuum freeze dryer, drying for 72 hours at the cold trap temperature of-56 ℃ and under the air pressure of 15Pa, and drying the dried sample for 4 hours at the normal pressure and 95 ℃.
Example 5
A preparation method of an aramid nanofiber aerogel comprises the following steps:
step 1, adding 2g of potassium hydroxide into 10ml of deionized water to obtain a solution A in which the potassium hydroxide is completely dissolved, adding 500ml of dimethyl sulfoxide into the solution A to obtain a mixed system B, adding 1g of para-aramid fiber in a form of short cut into the mixed system B, and continuously performing magnetic stirring at 25 ℃ for 24 hours to obtain a dark red dispersion liquid C, namely the aramid nanofiber dispersion liquid.
Step 2, mixing and stirring the aramid nano-fiber dispersion liquid and deionized water according to the volume ratio of 1:3 for 3 hours, washing to obtain a mixed system D, filtering the mixed system D on a 2800-mesh filter screen for 24 hours to remove residual potassium hydroxide and dimethyl sulfoxide, and obtaining gel with the aramid nano-fiber accounting for about 1.0%;
the deionized water is replaced by a mixed system of the deionized water and the tertiary butanol with the same volume, the system contains 20ml of the tertiary butanol, and the steps are repeated.
And 3, freezing the prepared aramid nano-fiber in a liquid nitrogen (-196 ℃) environment for 0.5h, putting the frozen sample into a vacuum freeze dryer, drying for 96h at the temperature of-56 ℃ of a cold trap and under the air pressure of 18Pa, and drying the dried sample for 3h at the normal pressure and the temperature of 95 ℃.
Example 6
A preparation method of an aramid nanofiber aerogel comprises the following steps:
step 1, adding 1g of sodium hydroxide into 10ml of deionized water to obtain a solution A with potassium hydroxide completely dissolved, adding 500ml of dimethyl sulfoxide into the solution A to obtain a mixed system B, adding 5g of para-aramid fiber with pulp form into the mixed system B, and continuously magnetically stirring for 24 hours at 25 ℃ to obtain a dark red dispersion liquid C, namely the aramid nanofiber dispersion liquid.
Step 2, mixing and stirring the aramid nano-fiber dispersion liquid and deionized water according to the volume ratio of 1:4 for 1 hour, washing to obtain a mixed system D, and filtering the mixed system D on a 2800-mesh filter screen for 12 hours to remove residual potassium hydroxide and dimethyl sulfoxide;
the deionized water is replaced by a mixed system of the deionized water and the tertiary butanol with the same volume, wherein the mixed system contains 15ml of the tertiary butanol, and the steps are repeated.
And 3, freezing the prepared aramid nano-fiber in a refrigerator (-10 ℃) environment for 24 hours, putting the frozen sample into a vacuum freeze dryer, drying for 76 hours at the cold trap temperature of-56 ℃ and the air pressure of 12Pa, and drying the dried sample for 2 hours at the normal pressure and the temperature of 100 ℃.
Example 7
A preparation method of an aramid nanofiber aerogel comprises the following steps:
step 1, adding 5g of potassium tert-butoxide into 10ml of deionized water to obtain a solution A in which the potassium tert-butoxide is completely dissolved, adding 500ml of dimethyl sulfoxide into the solution A to obtain a mixed system B, adding 2g of para-aramid fiber precipitated in the form of para-aramid fiber into the mixed system B, and continuously performing magnetic stirring at 25 ℃ for 24 hours to obtain a dark red dispersion liquid C, namely the aramid nanofiber dispersion liquid.
Step 2, mixing and stirring the aramid nano-fiber dispersion liquid and deionized water according to the volume ratio of 1:3.5 for 2 hours, washing to obtain a mixed system D, and filtering the mixed system D on a 2800-mesh filter screen for 16 hours to remove residual potassium tert-butoxide and dimethyl sulfoxide;
the deionized water is replaced by a mixed system of the deionized water and the tertiary butanol with the same volume, the system contains 5ml of the tertiary butanol, and the steps are repeated.
And 3, freezing the prepared aramid nano-fiber in a liquid nitrogen (-196 ℃) environment for 16 hours, putting the frozen sample into a vacuum freeze dryer, drying the sample for 80 hours at the cold trap temperature of-56 ℃ and the air pressure of 16Pa, and drying the dried sample for 3 hours at the normal pressure and the temperature of 105 ℃.
As shown in figure 1, the aramid nanofiber aerogel in example 1 is in a physical diagram, is fluffy and porous as a whole, has non-uniform pore size, and is snow-white.
As shown in fig. 2, which is an SEM image of the aramid nanofiber aerogel in example 1, the pore channels are in a disordered state, and the voids occupy a large proportion, which is not favorable for the strength of the aerogel framework.
As shown in fig. 3, a graph of an aramid nanofiber gel substance obtained in the example 2 after standing and filtering for 24 hours is determined, the aramid nanofiber content of the standing and filtering gel is 1% after 24 hours, the overall viscosity is high, and the aramid nanofiber gel substance does not have fluidity.
As shown in fig. 4, the aramid nanofiber aerogel in example 2 is a physical diagram, is fluffy and porous as a whole, is snow-white, and looks denser than that in comparative example 1.
As shown in fig. 5, which is an SEM image of the aramid nanofiber aerogel of example 2, the pore size is relatively ordered, and the proportion of pores is about half of the space.
As shown in fig. 6, which is an SEM image of the aramid nanofiber aerogel of example 3, the surface of the aerogel does not have open multiple pores, the whole aerogel is yellowish, and the color of the aerogel is similar to that of the aramid fiber.
As shown in fig. 7, which is an SEM image of the aramid nanofiber aerogel of example 3, the pore is large and continuous, and the proportion of pores is more than half, mainly due to slow freezing process and excessive ice crystal growth, which is not favorable for preparing uniform porous pore aerogel.
As shown in fig. 8, the aramid nanofiber aerogel in example 4 is in a physical diagram, has multiple holes on the surface, is fluffy as a whole, and is slightly white in color.
As shown in fig. 9, an SEM image of the aramid nanofiber aerogel of example 4 shows that the pore size is uniform, and the proportion of pores and the proportion of framework space are substantially equal, which indicates that the ice crystal growth process is well controlled, and is beneficial to preparing uniform porous aerogel.
As shown in fig. 10, the object graph of the aramid nanofiber aerogel of example 5 has fewer surface openings, is overall lightweight but does not feel fluffy, and has a color approaching to the color of the aramid fiber.
As shown in fig. 11, an SEM image of the aramid nanofiber aerogel of example 5 shows that pore sizes are not uniform, the proportion of pores and the proportion of skeleton space are substantially equal, and a certain number of small pores are present, which indicates that the growth process of ice crystals is generally controlled, and is beneficial to the preparation of other aerogel materials with special requirements.
Claims (10)
1. A preparation method of aramid nanofiber aerogel is characterized by comprising the following steps of,
step 1, firstly, preparing aramid fibers into an aramid nanofiber dispersion liquid by using solid A, deionized water and dimethyl sulfoxide, wherein the solid A is potassium hydroxide, sodium hydroxide or potassium tert-butoxide, then uniformly mixing the aramid nanofiber dispersion liquid and the deionized water according to the volume ratio of 1 (3-4) to obtain a mixed system A, and finally filtering the mixed system A to obtain aramid nanofiber gel;
the aramid nano-fiber dispersion liquid is obtained by the following steps,
step 1a, mixing a solid A and deionized water to obtain a solution A;
step 1b, according to 1: adding dimethyl sulfoxide into the solution A according to the volume ratio of 50 to obtain a mixed system a;
step 1c, according to (1-5) g: adding aramid fibers into the mixed system a according to the proportion of 510ml, and uniformly mixing to obtain an aramid nanofiber dispersion liquid;
and 2, sequentially freezing, vacuum drying and normal-pressure drying the aramid nano-fiber gel to obtain the aramid nano-fiber aerogel.
2. The preparation method of the aramid nanofiber aerogel according to claim 1, wherein a mixed system of tert-butyl alcohol and deionized water is added into the aramid nanofiber aerogel in the step 2, and the mixture is filtered and then frozen.
3. The preparation method of the aramid nanofiber aerogel according to claim 2, wherein the filtering in the step 1 and the filtering in the step 2 are performed in a manner of filtering for 12-24 hours by using a filter screen.
4. The preparation method of the aramid nanofiber aerogel according to claim 2, wherein in the step 2, the volume ratio of the tert-butyl alcohol to the aramid nanofiber dispersion liquid is < (20: 510).
5. The preparation method of the aramid nanofiber aerogel according to claim 1, wherein in the step 1, the aramid nanofiber dispersion liquid and deionized water are stirred for 1-3 hours to obtain a mixed system A.
6. The preparation method of the aramid nanofiber aerogel according to claim 1, wherein in the step 2, the freezing temperature is-196 to-5 ℃, and the freezing time is 0.5 to 24 hours;
the vacuum drying temperature is-56 ℃, the air pressure is 12-18 Pa, and the time is 72-96 h.
7. The preparation method of the aramid nanofiber aerogel according to claim 1, wherein in the step 2, the temperature of the atmospheric drying is 95-105 ℃, and the time is 2-4 hours.
8. The preparation method of the aramid nanofiber aerogel according to claim 1, wherein in the step 1a, the mixing ratio of the solid A to the deionized water is (1-5) g: 10 ml.
9. The method for preparing the aramid nanofiber aerogel according to claim 1, wherein the aramid fiber is para-aramid fiber, and the form of the para-aramid fiber is chopped, filament, precipitated or pulp.
10. An aramid nanofiber aerogel obtained by the method for preparing the aramid nanofiber aerogel as claimed in any one of claims 1 to 9.
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112876728A (en) * | 2021-02-04 | 2021-06-01 | 江苏大学 | Preparation method and application of chemical fiber aerogel |
| CN112980044A (en) * | 2021-03-18 | 2021-06-18 | 航天特种材料及工艺技术研究所 | High-performance bulk aramid nanofiber aerogel and preparation method and application thereof |
| CN113278191A (en) * | 2021-05-28 | 2021-08-20 | 陕西科技大学 | Aramid nanofiber-based composite aerogel and preparation method thereof |
| CN113506949A (en) * | 2021-07-09 | 2021-10-15 | 陕西科技大学 | Preparation method of aramid nanofiber-based battery diaphragm with micro-nano porous structure |
| CN113756100A (en) * | 2021-09-09 | 2021-12-07 | 北京理工大学重庆创新中心 | Preparation method of flexible protection structure with heat insulation, flame retardance and self-cleaning performance |
| CN114479163A (en) * | 2022-01-04 | 2022-05-13 | 煤炭科学研究总院有限公司 | Modified para-aramid nanofiber aerogel and preparation method and application thereof |
| CN114481680A (en) * | 2022-03-10 | 2022-05-13 | 咸宁优维科技有限公司 | Preparation method of aramid fiber material and superfine meta-position and para-position aramid fiber film, sponge and aerogel material prepared by same |
| CN115160636A (en) * | 2022-08-16 | 2022-10-11 | 南京信息工程大学 | Aramid nano-fiber aerogel balls and preparation method thereof |
| CN115322430A (en) * | 2022-07-25 | 2022-11-11 | 成都飞机工业（集团）有限责任公司 | Wave-absorbing aerogel composite material and preparation method thereof |
| CN115558152A (en) * | 2022-10-14 | 2023-01-03 | 南京农业大学 | Dual-drying degradable nano-cellulose composite antibacterial aerogel and preparation method and application thereof |
| CN116655996A (en) * | 2023-05-24 | 2023-08-29 | 福建农林大学 | Aramid nanofiber/nanocellulose composite aerogel and preparation method and application thereof |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106977763A (en) * | 2017-04-20 | 2017-07-25 | 哈尔滨工业大学 | A kind of preparation method of aramid nano-fiber aeroge |
| US20190062517A1 (en) * | 2015-02-05 | 2019-02-28 | Aerogel Technologies, Llc | Systems and methods for producing aerogel material |
-
2020
- 2020-04-28 CN CN202010350965.9A patent/CN111333900B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20190062517A1 (en) * | 2015-02-05 | 2019-02-28 | Aerogel Technologies, Llc | Systems and methods for producing aerogel material |
| CN106977763A (en) * | 2017-04-20 | 2017-07-25 | 哈尔滨工业大学 | A kind of preparation method of aramid nano-fiber aeroge |
Non-Patent Citations (1)
| Title |
|---|
| 李怀宇: ""芳纶基纳米纤维气凝胶的制备及其碳化工艺的研究"", 《中国优秀博硕士学位论文全文数据库(硕士) 工程科技Ⅰ辑》 * |
Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112876728A (en) * | 2021-02-04 | 2021-06-01 | 江苏大学 | Preparation method and application of chemical fiber aerogel |
| CN112980044A (en) * | 2021-03-18 | 2021-06-18 | 航天特种材料及工艺技术研究所 | High-performance bulk aramid nanofiber aerogel and preparation method and application thereof |
| CN113278191A (en) * | 2021-05-28 | 2021-08-20 | 陕西科技大学 | Aramid nanofiber-based composite aerogel and preparation method thereof |
| CN113506949A (en) * | 2021-07-09 | 2021-10-15 | 陕西科技大学 | Preparation method of aramid nanofiber-based battery diaphragm with micro-nano porous structure |
| CN113756100A (en) * | 2021-09-09 | 2021-12-07 | 北京理工大学重庆创新中心 | Preparation method of flexible protection structure with heat insulation, flame retardance and self-cleaning performance |
| CN114479163A (en) * | 2022-01-04 | 2022-05-13 | 煤炭科学研究总院有限公司 | Modified para-aramid nanofiber aerogel and preparation method and application thereof |
| CN114481680A (en) * | 2022-03-10 | 2022-05-13 | 咸宁优维科技有限公司 | Preparation method of aramid fiber material and superfine meta-position and para-position aramid fiber film, sponge and aerogel material prepared by same |
| CN114481680B (en) * | 2022-03-10 | 2023-08-22 | 咸宁优维科技有限公司 | Preparation method of aramid fiber material, aerogel and pumping filter membrane material |
| CN115322430A (en) * | 2022-07-25 | 2022-11-11 | 成都飞机工业（集团）有限责任公司 | Wave-absorbing aerogel composite material and preparation method thereof |
| CN115322430B (en) * | 2022-07-25 | 2023-10-03 | 成都飞机工业（集团）有限责任公司 | Wave-absorbing aerogel composite material and preparation method thereof |
| CN115160636A (en) * | 2022-08-16 | 2022-10-11 | 南京信息工程大学 | Aramid nano-fiber aerogel balls and preparation method thereof |
| CN115160636B (en) * | 2022-08-16 | 2023-10-13 | 南京信息工程大学 | Aramid nanofiber aerogel ball and preparation method thereof |
| CN115558152A (en) * | 2022-10-14 | 2023-01-03 | 南京农业大学 | Dual-drying degradable nano-cellulose composite antibacterial aerogel and preparation method and application thereof |
| CN116655996A (en) * | 2023-05-24 | 2023-08-29 | 福建农林大学 | Aramid nanofiber/nanocellulose composite aerogel and preparation method and application thereof |
| CN116655996B (en) * | 2023-05-24 | 2024-03-26 | 福建农林大学 | Aramid nanofiber/nanocellulose composite aerogel and preparation method and application thereof |
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