High-performance polymer fiber-based aerogel fibers and methods of making and using the same

Abstract

The application provides a high-performance polymer fiber-based aerogel fiber and a preparation method and application thereof, and the preparation method comprises the following steps: using a gel spinning technology to obtain a high-performance polymer gel fiber by using a proton absorber in a coagulation bath through a high-performance polymer fiber precursor; and then sequentially performing solvent replacement, aging, drying and heat treatment to obtain the high-performance polymer fiber-based aerogel fiber; wherein the high-performance polymer fiber precursor is a homogeneous nanofiber dispersion liquid prepared by solution reaction of a high-performance polymer and a first protonic acid. The high-performance polymer fiber-based aerogel fiber is prepared by the method of dissolving the polymer by using the protonic acid and supplemented by adding the proton absorber, and has the characteristics of high strength, low thermal conductivity, high porosity, continuous spinnability, good flexibility, strong weavability and excellent skeleton structure stability.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of nano-porous materials and functional fibers, and particularly relates to a high-performance polymer fiber-based aerogel fiber and a preparation method and application thereof. BACKGROUND

[0002] From animal and plant fibers, such as hair, wool and cotton, to synthetic fibers, such as polyester, nylon and acrylic, fibers have been one of the most abundant and useful forms of matter for human service. So far, fibers with some special structures and functions, such as hollow fibers, microfibers and down, etc., are the first choice for thermal insulation fabrics, and these fibers can exceed the performance limit of animal and plant fibers or solid fibers produced by traditional manufacturing methods.

[0003] Compared with solid fibers, these fibers have special structures that can better retain heat. On the one hand, the high insulation performance is mainly due to the high surface area and high gas retention between / inside the fibers. On the other hand, the main influence of thermal insulation on thermal performance depends on the density, porosity, specific surface area and number and size of pores in the material. Studies have shown that when the pore size is reduced to the nanometer range, the heat conduction through the closed gas phase is limited due to the Knudsen effect, and the thermal conductivity is reduced. Therefore, structures containing large pore volumes can effectively insulate and serve as substitutes for synthetic fibers with excellent thermal regulation performance. In summary, in order to make the prepared fibers have high insulation, thermal insulation and other comprehensive performance, the prepared fibers should be as porous as possible to capture more air, have ultra-low density to reduce solid-phase heat conduction and small pore size to limit heat convection.

[0004] Aerogel is one of the lightest solid materials known, and is a material with a three-dimensional porous network structure, with high porosity and large specific surface area. Compared with other porous materials, the pore size and distribution of aerogel material are more uniform, the surface area is larger, the porosity is higher, and at the same time, it has extremely low density and thermal conductivity, so that it shows excellent performance in the fields of drug release, energy conversion, intelligent sensing, etc., especially in thermal insulation.

[0005] The performance of aerogels depends on their microstructure and the properties of the constituent framework. Traditional aerogel fibers (silica, titanium oxide) are difficult to apply to the human body due to stress concentration caused by their pearl chain-like microstructure. Aerogel fibers composed of two-dimensional nanosheet materials (graphene, MXene) lack comfort and skin affinity, limiting scalability and commercial viability. In view of this, polymer-based aerogel fibers, such as cellulose aerogel fibers, silk protein aerogel fibers, and PVA aerogel fibers, have made great progress due to their insulation performance and comfort. However, due to the molecular structure and composition of aerogel fibers, these aerogel fibers usually melt or decompose at high temperatures, and even brittle fracture occurs at low temperatures, limiting their application range.

[0006] In addition, the continuous and large-scale preparation of aerogel materials using modern technology is also a problem to be solved. Therefore, the design of high-performance polymer aerogel fibers with high performance and a universal manufacturing method is still a challenge.

[0007] High-performance polymer aerogel fibers have excellent flexibility compared to traditional aerogels or bulk materials, have good weavability, and are more convenient to apply in different fields. However, in the preparation process of traditional aerogel fibers, the gelation process is rapid and uncontrollable, making it impossible to continuously process gel fibers, and only short fibers can be prepared. For example, Chinese invention patent CN201810443578.2 discloses a polyamide aerogel fiber, its preparation method and application. When the gel fiber is dried to obtain an aerogel, the state of different amides in the solvent is difficult to control, and the dimensional stability is poor. At the same time, due to its porous structure, the mechanical properties of the aerogel fiber are poor, making it difficult to meet the mechanical requirements of weaving. It is a scientific problem to be solved to ensure the porous performance of the aerogel fiber while ensuring its high mechanical properties. Chinese invention patent CN202211136923.0 discloses a preparation method of an aromatic polyamide aerogel fiber. Although this method uses a protonic acid to obtain a spinning solution, the gelation process does not further control the proton removal rate, which has a great impact on the mechanical properties and shrinkage of the gel fiber.

[0008] In summary, although the preparation of aerogel fibers has made great progress, so far, high-performance polymer fiber aerogel fibers with high temperature resistance and good mechanical strength have not been completely developed, which limits the popularization of aerogel fibers in practical applications.

[0009] Based on the above technical problems, the present application directly uses high-performance polymers to react with protonic acid to form a homogeneous nanofiber, and then controls the wet gel spinning process through a proton absorber. By controlling the addition of the proton absorber during the spinning process, the nanofiber can be uniformly and controllably gelled. Meanwhile, the high-performance polymer aerogel fiber material can be continuously and large-scale prepared quickly during the spinning process, and the precursor range is wide. SUMMARY

[0010] Therefore, to solve the above problems, the present application provides a high-performance polymer fiber-based aerogel fiber and a preparation method and application thereof, aiming to solve the problem that the prior art cannot prepare aerogel fibers through heterocyclic polymers (polyphenylene pyridine imidazole, poly-p-phenylene benzodithiazole, and poly-p-phenylene benzodioxazole), and overcome the deficiency of complex preparation procedure in the prior art aromatic aerogel technology.

[0011] To achieve the above purpose, the present application provides a preparation method of a high-performance polymer fiber-based aerogel fiber, comprising: using a gel spinning technology to obtain a high-performance polymer gel fiber by using a proton absorber in a coagulation bath through a high-performance polymer fiber precursor; and then obtaining the high-performance polymer fiber-based aerogel fiber after aging, drying, and heat treatment in sequence.

[0012] Preferably, the high-performance polymer fiber precursor is a homogeneous nanofiber dispersion liquid prepared by solution reaction of a high-performance polymer and a protonic acid. In this process, the polymer and the acid interact, the polymer is protonated, the intermolecular repulsive force increases, branching and separation occur, and a nanofiber dispersion liquid is formed. The nanofiber dispersion liquid is dynamically gelled by a controllable proton-absorbing coagulation bath. During the gelling process, the protons are absorbed by the proton absorber of the coagulation bath, reducing the interaction between the polymer molecules. The proton absorber is a complex solvent system, forming a gel fiber. After further solvent replacement and drying, the gel fiber becomes an aerogel fiber.

[0013] Preferably, the preparation method of the high-performance polymer fiber-based aerogel fiber comprises the following steps:

[0014] S1. Preparation of a high-performance polymer fiber precursor: dissolving the high-performance polymer in the protonic acid to perform a protonation reaction, and forming a homogeneous nanofiber dispersion liquid, which is the high-performance polymer fiber precursor;

[0015] S2. Preparation of a nanofiber gel fiber: controlling the wet gel spinning of the high-performance polymer fiber precursor in a coagulation bath through a proton absorber to obtain the nanofiber gel fiber;

[0016] S3. Preparation of aerogel nascent fibers: The gel fibers of the nanofibers are left to stand and then aged to obtain wet gel fibers; the wet gel fibers are dried to obtain the aerogel nascent fibers.

[0017] S4. Preparation of polymer fiber-based aerogel fibers: The polymer fiber-based aerogel fibers are obtained by heat treatment of the aerogel nascent fibers at high temperature.

[0018] Preferably, the polymer in the high-performance polymer fiber includes at least one of polyphenylenepyridinium imidazole, poly(p-phenylenebenzobisthiazole), poly(p-phenylenebenzobisoxazole), poly-p-phenylene terephthalamide, poly(p-phenylene terephthalamide), and poly(p-phenylene terephthalamide) copolymerized with phthaloyldiphenylamine; or at least one of the above polymers containing functional substituents.

[0019] Preferably, the polymer fiber includes at least one of Kevlar, Nomex, Twaron, Technora, Terlon, Taparan, SVM, Armors, F3, M5, and Zylon.

[0020] Preferably, the high-performance polymer fiber is in the form of at least one of blocks, fibers, paper, pulp, and powder.

[0021] Preferably, the coagulation bath is obtained by allowing a mixed solution of a first solvent, a second protic acid, and the proton absorber to stand.

[0022] Preferably, the proton absorber comprises at least one or a mixture of two or more of ethyl formate, ethyl acetate, ethyl butyrate, and gluconolactone.

[0023] Preferably, the first solvent is at least one or a mixture of two or more of water, methanol, ethanol, and acetone.

[0024] Preferably, the mass ratio of the first solvent: the proton absorber: the proton acid is (5-70):(10-25):(20-70).

[0025] Preferably, the first protic acid and the second protic acid each include at least one of methanesulfonic acid, sulfuric acid, trifluoroacetic acid, trichloroacetic acid, nitric acid, and nitromethane.

[0026] More preferably, it is at least one of trifluoroacetic acid, methanesulfonic acid, and sulfuric acid.

[0027] Preferably, the high-performance polymer fiber precursor is composed of nanofibers; the mass fraction of the high-performance polymer fiber precursor is 0.01 to 25 wt%.

[0028] More preferably, 0.1-10 wt%.

[0029] Preferably, the mass ratio of the high-performance polymer fiber to the protonic acid is 1:4-1:500.

[0030] Preferably, the dissolving temperature of the high-performance polymer fiber in the protonic acid is 25-120°C, preferably 40-80°C.

[0031] Preferably, the reaction time is 10h-7 days.

[0032] More preferably, 1 day-3 days.

[0033] Preferably, the aging-drying-heat treatment method comprises obtaining high-performance polymer gel fibers by the wet gel spinning technology of the protonic absorbent in the coagulation bath from the nanofiber dispersion liquid, and after standing, the high-performance polymer gel fibers are aged to obtain nanofiber wet gel fibers; the nanofiber wet gel fibers are subjected to drying treatment, and then high-temperature heat treatment in a selected gas atmosphere to obtain high-performance polymer fiber-based aerogel fibers.

[0034] Preferably, the standing time is 3-5 days.

[0035] Preferably, the aging time is 5-48h, preferably 10-24h.

[0036] Preferably, the drying method comprises two steps of solvent replacement and gas-liquid exchange drying.

[0037] Preferably, the solvent replacement is replaced with the second solvent for at least 5 times, and the interval time is at least 3-5h.

[0038] Preferably, the second solvent comprises at least one of water, ethanol, tert-butanol, dioxane, phenol, and acetone.

[0039] Preferably, the gas-liquid exchange drying method comprises at least one of supercritical drying, freeze drying, vacuum drying, atmospheric drying, spray drying, heat drying, and radiation drying.

[0040] Preferably, the high-temperature heat treatment temperature is 350-630°C, and the time is 1min-1h.

[0041] And / or, the selected gas atmosphere comprises at least one of nitrogen, argon, air, helium, and carbon dioxide.

[0042] The high-performance polymer fiber-based aerogel fiber prepared by the preparation method provided in the technical solution has a multi-level pore structure, which is composed of micropores with a pore diameter of less than 2 nm, mesopores with a pore diameter of 2-50 nm and macropores with a pore diameter of > 50 mu m, and is constructed by nanofibers; the high-performance polymer aerogel fiber has a density of 0.1-200 mg / cm 3 , a porosity of 60%-99.99%, a specific surface area of 1-1000 m 2 / g, a tensile strength of 0.1-40 MPa and a thermal conductivity of 10-100 mw / (m·k).

[0043] The preparation mechanism of the present application may be that after the high-performance polymer is reacted with a protonic acid, protonation occurs, the repulsion between the chains increases, nanofibers are generated, and under the action of a long time, a nanofiber dispersion is formed in the solvent. The proton absorber can slowly absorb the protons of the dispersion, continuously gel in the coagulation bath, form a uniform gel fiber, and obtain the high-performance polymer aerogel fiber through solvent exchange and gas-liquid alternating drying.

[0044] Another aspect of the embodiment of the present application also provides the application of the aerogel fiber.

[0045] The high-performance polymer fiber-based aerogel fiber provided by the present application has an extremely low apparent density of 0.1-200 mg / cm 3 , an adjustable porosity of 60%-99.99%, a specific surface area of 1-1000 m 2 / g, a tensile strength of 0.1-40 MPa and a thermal conductivity of 10-100 mw / (m·k). The preparation method provided by the present application is simple and easy to implement. The high-performance polymer fiber-based aerogel fiber has a wide application prospect in the fields of personal clothing thermal management, composite materials, intelligent wearable devices, fiber fluff, thermal insulation under extreme conditions, filtration materials and the like.

[0046] According to the above technical solution, the aerogel fiber provided by the present application has good mechanical strength, high specific surface area and high porosity, excellent thermal stability, heat insulation performance and the like, and has a very wide application prospect.

[0047] The present application has the following beneficial technical effects:

[0048] 1. The technical solution of the present application adopts the method of dissolving the polymer by using a protonic acid, and adds a proton absorber to prepare the high-performance polymer fiber-based aerogel fiber, which has the characteristics of high strength, ultra-high toughness, low thermal conductivity, high porosity, continuous spinnability, good flexibility, strong weavability and excellent skeleton structure stability.

[0049] 2. The polymer fiber-based aerogel fiber prepared by the technical scheme of the present application not only has excellent physical properties, but also has good heat insulation and heat preservation performance due to the multi-level pore structure, so that it can be applied to the knitting technical field and the heat insulation and heat preservation material technical field, and can be widely applied.

[0050] 3. The high-performance polymer fiber-based aerogel fiber prepared by the technical scheme of the present application has simple preparation process, mild reaction conditions, can be continuously prepared, has low energy consumption, and can be applied to industrial production, mass production and popularization. BRIEF DESCRIPTION OF DRAWINGS

[0051] In order to more clearly illustrate the technical scheme in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments described in the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0052] Figure 1 is an optical photo of the appearance of the high-performance polymer aerogel fiber material prepared in Example 1 of the present application.

[0053] Figure 2 is a scanning electron microscope graph of the high-performance polymer aerogel fiber material prepared in Example 2 of the present application.

[0054] Figure 3 is a nitrogen adsorption-desorption curve graph of the high-performance polymer aerogel fiber material prepared in Example 2 of the present application.

[0055] Figure 4 is a nitrogen adsorption-desorption curve graph of the high-performance polymer aerogel fiber material prepared in Example 5 of the present application.

[0056] Figure 5 is an infrared graph of the high-performance polymer aerogel fiber material prepared in Example 5 of the present application after the high-temperature hot table.

[0057] Figure 6 is a scanning electron microscope graph of the high-performance polymer aerogel fiber material prepared in Example 10 of the present application.

[0058] Figure 7 is a scanning electron microscope graph of the high-performance polymer aerogel fiber material prepared in Example 11 of the present application. DETAILED DESCRIPTION

[0059] In order to make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application.

[0060] The present application provides a method for preparing high-performance polymer aerogel fibers, which is an aspect of an embodiment of the present application, and the method comprises the following steps:

[0061] Protonating and reacting the high-performance polymer fibers in a protonic acid to form a homogeneous nanofiber dispersion;

[0062] Controlling the wet gel spinning of the nanofiber dispersion in a proton absorber to obtain wet gel fibers after the gel fibers are left to stand and age;

[0063] Performing solvent replacement, aging, gas-liquid exchange drying treatment and high-temperature heat treatment on the wet gel fibers to obtain high-performance polymer aerogel fibers.

[0064] In some embodiments, the method for preparing high-performance polymer aerogel fibers comprises the following steps: firstly, mixing high-performance polymer raw materials (fibers, pulp or powder) and a protonic acid, reacting the mixture at a certain temperature to form a homogeneous nanofiber dispersion, and controlling the wet gel spinning of the nanofiber dispersion in a proton absorber to obtain wet gel fibers after the gel fibers are left to stand and age; and then, obtaining high-performance polymer aerogel fibers through solvent replacement, gas-liquid exchange drying and high-temperature heat treatment. During the preparation process, the polymer interacts with the acid, the polymer is protonated, the intermolecular repulsive force increases, branching and separation occur, and a nanofiber dispersion is formed; the nanofiber dispersion is dynamically gelled through a coagulation bath with controllable proton absorption, and during the dynamic gelling process, the protons are absorbed by the proton absorber of the coagulation bath, thereby reducing the interaction between the polymer molecules, and then forming gel fibers, which are dried to obtain aerogel fibers after further solvent replacement.

[0065] In some more specific embodiments, the method for preparing high-performance polymer aerogel fibers comprises the following steps:

[0066] (1) Preparation of high-performance polymer fiber precursor: dissolving the high-performance polymer in the protonic acid to perform protonation reaction, and forming a homogeneous nanofiber dispersion, which is the high-performance polymer fiber precursor;

[0067] (2) Preparation of nanofiber gel fibers: controlling the wet gel spinning of the high-performance polymer fiber precursor in a coagulation bath through a proton absorber to obtain the nanofiber gel fibers;

[0068] (3) Preparation of aerogel nascent fiber: the gel fiber of the nanofiber is aged after standing to obtain a wet gel fiber; the wet gel fiber is dried to obtain the aerogel nascent fiber;

[0069] (4) Preparation of polymer fiber-based aerogel fiber: the aerogel nascent fiber is high-temperature treated to obtain the polymer fiber-based aerogel fiber.

[0070] The preparation mechanism of the present application can be that: after the high-performance polymer is reacted with a protonic acid, protonation occurs, the repulsion between the molecular chains increases, nanofibers are generated, and under the action of a long time, a nanofiber dispersion is finally formed in the solvent. The proton absorber can slowly absorb the protons of the dispersion, continuously gel in the coagulation bath, and form uniform gel fibers. Then, solvent exchange and gas-liquid interactive drying are performed to obtain high-performance polymer aerogel fibers.

[0071] In some embodiments, in step (1), the material of the high-performance polymer fiber includes at least one of polybenzotriazole, polybenzodithiazole, polybenzodioxazole, poly-p-phenylene terephthalamide, poly-m-phenylene isophthalamide, poly-m-phenylene terephthalamide, and the above-mentioned related polymers containing functional substituents, and preferably, the high-performance polymer fiber includes at least one of Kevlar, Nomex, Twaron, Technora, Terlon, Taparan, SVM, Armors, F3, M5, and Zylon, but is not limited thereto.

[0072] In some embodiments, the form of the raw material includes at least one of blocks, fibers, paper, pulp, or powder, but is not limited thereto. The selection of the raw material in the preparation method of the present application has a wide range of selection directions and is not directly related to the shape of the raw material.

[0073] In some embodiments, in step (1), the coagulation bath used includes a mixed solution of a solvent, a protonic acid, and a proton absorber. The protonic acid includes at least any one or a mixture of two or more of methane sulfonic acid, sulfuric acid, trifluoroacetic acid, trichloroacetic acid, nitric acid, and nitromethane; the solvent is at least any one or a mixture of two or more of water, methanol, ethanol, and acetone; the proton absorber is at least any one or a mixture of two or more of ethyl formate, ethyl acetate, ethyl butyrate, and gluconolactone; and the mass ratio of the solvent, the proton absorber, and the protonic acid is (5-70):(10-25):(20-70), but is not limited thereto.

[0074] In some embodiments, in step (1), the high-performance polymer fiber precursor is composed of nanofibers; the mass fraction of the high-performance polymer fiber precursor is 0.01-25 wt%, preferably 0.1-10 wt%; by controlling the ratio and matching mode of different protonic acids and raw materials of the high-performance polymer, the present application can realize the microstructure regulation of nanofibers and regulate the overall structure of aerogels.

[0075] In some embodiments, in step (1), the mass fraction of the high-performance polymer raw material (Kevlar, Nomex, Twaron, Technora, Terlon, Taparan, SVM, Armors, F3, M5, Zylon) in the nanofiber dispersion liquid is 0.01-25 wt%, preferably 0.1-10 wt%. The present application can obtain a nanofiber dispersion liquid that is uniformly distributed and completely dispersed, and in addition, by regulating the mass fraction, the density of the aerogel can also be regulated, specifically, the density of the aerogel is high and increases with the increase of the mass fraction, and the diameter and number of the spinning hole can also be regulated to control the diameter and number of the fibers.

[0076] In some embodiments, in step (1), the temperature of the reaction is 25-120°C, and the reaction time is 10 h-7 d.

[0077] In some embodiments, in step (2), the coagulation bath used includes a mixed solution of a solvent, a protonic acid, and a proton acceptor, which is obtained after the mixed solution is left to stand after being matched in a certain ratio. The protonic acid includes methane sulfonic acid, sulfuric acid, trifluoroacetic acid, trichloroacetic acid, nitric acid; the solvent is at least any one or a mixture of two or more of water, methanol, ethanol, and acetone; the proton acceptor is at least any one or a mixture of two or more of ethyl formate, ethyl acetate, ethyl butyrate, and gluconolactone; wherein the mass ratio of the solvent, the proton acceptor, and the protonic acid is (5-70):(10-25):(20-70).

[0078] Preferably, the mass ratio of the solvent, the proton acceptor, and the protonic acid is (10-65):25:(25-65).

[0079] In some embodiments, in step (3), the standing and aging time is 0-5 days, preferably 2-3 days. With the extension of the aging time, the nanofiber skeleton structure can be sufficiently improved, and the strength of the aerogel fiber is increased.

[0080] In some embodiments, in step (3), the solvent used in solvent replacement includes at least one of water, ethanol, tert-butyl alcohol, dioxane, phenol, acetone, and the replacement is performed at least 5 times with an interval of at least 3-5 hours; and / or, the gas-liquid exchange drying method includes at least one of supercritical drying, freeze drying, vacuum drying, normal pressure drying, spray drying, heat drying, and radiation drying.

[0081] In some embodiments, in step (3), the gas-liquid exchange drying method includes at least one of supercritical drying, freeze drying, vacuum drying, normal pressure drying, spray drying, heat drying, and radiation drying, but is not limited thereto.

[0082] In some embodiments, in step (3), the selected atmosphere includes at least one of nitrogen, argon, air, helium, and carbon dioxide, but is not limited thereto.

[0083] In some embodiments, in step (4), the high-temperature heat treatment is performed at a temperature of 350-630 DEG C for 1 minute to 1 hour, and the heat cross-linking and micro-carbonization during the high-temperature heat treatment process generate cross-linking points and increase the skeleton strength.

[0084] Further, the nano-fiber structure obtained by the protonation method is controllable, the aerogel fiber is assembled by nano-fibers to form a multi-level pore structure, the shrinkage of the material is extremely low by controlling the proton absorption, the density of the obtained high-performance polymer aerogel fiber has an extremely low apparent density, the multi-level pore structure is composed of micropores with a pore size of less than 2 nm, mesopores with a pore size of 2-50 nm, and macropores with a pore size of > 50 mu m; the density of the high-performance polymer aerogel fiber is 0.1-200 mg / cm 3 , the porosity is 60%-99.99%, the specific surface area is 1-1000 m 2 / g, and the tensile strength is 0.1-40 MPa, and the thermal conductivity is 10-100 mw / (m·k). The preparation method provided by the application is simple and easy to implement.

[0085] Another aspect of the embodiment of the application also provides the application of the aerogel fiber.

[0086] The high-performance polymer fiber-based aerogel fiber provided by the application has an extremely low apparent density of 0.1-200 mg / cm 3 , which can be adjusted, and has a wide application prospect in the fields of personal clothing thermal management, composite materials, intelligent wearable devices, fiber fluff, thermal insulation under extreme conditions, and filtration materials.

[0087] By the technical scheme, the aerogel fiber has good mechanical strength, high specific surface area, high porosity, excellent thermal stability and heat insulation performance, and has a wide application prospect.

[0088] The technical scheme of the present application will be further described in detail through specific examples.

[0089] Example 1

[0090] The present embodiment provides a preparation method of high-performance polymer fiber-based aerogel fiber, and the specific steps include:

[0091] (1) Preparation of high-performance polymer fiber precursor: 1g of Zylon fiber is weighed and added to 99g of methane sulfonic acid, and stirred at room temperature (25℃) at 1000rpm for 3 days until a uniform aramid nanofiber dispersion is formed, wherein the mass fraction of Zylon nanofiber is 1%, and the obtained nanofiber dispersion is the high-performance polymer fiber precursor.

[0092] (2) Preparation of Zylon nanofiber gel fiber: 55g of methane sulfonic acid, 25g of water and 25g of ethyl acetate are mixed uniformly to obtain a proton absorber, and the obtained Zylon nanofiber dispersion precursor is extruded by a wet spinning method at an extrusion speed of 150μL / min and a spinning needle diameter of 300μm to obtain Zylon nanofiber gel fiber.

[0093] (3) Preparation of Zylon aerogel nascent fiber: the Zylon nanofiber gel fiber obtained in step (2) is aged for 2 days, replaced with t-butyl alcohol and water (V / V=1:1) for 8 times with an interval of 3h, and Zylon nanofiber wet gel fiber is obtained, and the Zylon aerogel nascent fiber is obtained by freeze-drying at-55℃.

[0094] (4) Preparation of polymer fiber-based aerogel fiber: the Zylon aerogel nascent fiber prepared in step (3) is heat treated at 600℃ for 10min under nitrogen to obtain Zylon aerogel fiber, and the polymer fiber-based aerogel fiber is obtained.

[0095] Reference Figure 1 The optical picture of the polymer fiber-based aerogel fiber obtained by the above steps of the present embodiment is shown in the figure. As can be seen from the figure, the appearance of the aerogel fiber prepared by the present embodiment is uniform, or in other words, the aerogel fiber prepared by the method provided by the present embodiment is uniform in thickness, and obviously, the aerogel fiber prepared by the present embodiment has the potential of being woven, and can be applied in the fields of personal clothing thermal management, composite materials, intelligent wearable devices, etc., and has the potential of batch preparation and production.

[0096] Example 2

[0097] This embodiment provides a method for preparing high-performance polymer fiber-based aerogel fibers, the specific steps of which include:

[0098] (1) Preparation of high-performance polymer fiber precursor: Weigh 1g of Zylon fiber and add it to 99g of methanesulfonic acid. Stir at 1000rpm for 3 days at room temperature (25℃) until a uniform aramid nanofiber dispersion is formed, wherein the mass fraction of Zylon nanofiber is 1%. The obtained nanofiber dispersion is the high-performance polymer fiber precursor.

[0099] (2) Preparation of Zylon nanofiber gel fibers: 40g of methanesulfonic acid, 25g of water, and 35g of ethyl acetate were weighed and mixed evenly to obtain a proton absorber. The Zylon nanofiber dispersion precursor obtained above was extruded by wet spinning at an extrusion speed of 150μL / min through a spinning needle with a diameter of 300μm to obtain Zylon nanofiber gel fibers.

[0100] (3) Preparation of Zylon aerogel nascent fibers: The Zylon nanofibers obtained in step (2) were aged for 2 days and replaced with tert-butanol and water (V / V = 1:1) 8 times, with an interval of 3 hours each time, to obtain wet Zylon nanofibers. They were then freeze-dried at -55℃ to obtain Zylon aerogel nascent fibers.

[0101] (4) Preparation of polymer fiber-based aerogel fiber: The Zylon aerogel nascent fiber prepared in step (3) is subjected to high temperature heat treatment at 550℃ for 20 min under nitrogen to obtain Zylon aerogel fiber and thus polymer fiber-based aerogel fiber.

[0102] The specific properties of the polymer fiber-based aerogel fibers obtained in this embodiment after the above steps are shown in Table 1.

[0103] See Figure 2 The image shows a scanning electron microscope (SEM) image of the polymer fiber-based aerogel fiber obtained by the above steps in this embodiment. As can be seen from the image, the aerogel fiber prepared in this embodiment is constructed and assembled from nanofibers and forms a hierarchical porous structure. The hierarchical porous structure consists of micropores with a pore size of less than 2 nm, mesopores with a pore size of 2 to 50 nm, and macropores with a pore size of >50 μm.

[0104] like Figure 3 The figure shows the nitrogen adsorption-desorption curve of the high-performance polymer aerogel fiber material prepared by the above steps. As can be seen from the figure, the aerogel fiber exhibits a typical type IV adsorption-desorption curve, which proves that the aerogel has a large number of mesoporous structures.

[0105] Example 3

[0106] The present embodiment provides a method for preparing a high-performance polymer fiber-based aerogel fiber, and the specific steps include:

[0107] (1) Preparation of high-performance polymer fiber precursor: 1 g of Zylon fiber was weighed and added to 99 g of methane sulfonic acid, and stirred at 1000 rpm at room temperature (25°C) for 3 days until a uniform aramid nanofiber dispersion was formed, wherein the mass fraction of Zylon nanofiber was 1%, and the obtained nanofiber dispersion was the high-performance polymer fiber precursor.

[0108] (2) Preparation of Zylon nanofiber gel fiber: 60 g of methane sulfonic acid, 15 g of water, and 25 g of ethyl acetate were mixed uniformly to obtain a proton absorber, and the Zylon nanofiber dispersion precursor obtained above was extruded by a wet spinning method to obtain a Zylon nanofiber gel fiber with an extrusion speed of 150 μL / min and a spinning needle diameter of 300 μm.

[0109] (3) Preparation of Zylon aerogel nascent fiber: The Zylon nanofiber gel fiber obtained in step (2) was aged for 2 days, and was replaced with t-butyl alcohol and water (V / V = 1:1) for 8 times with an interval of 3 h each time to obtain a Zylon nanofiber wet gel fiber, which was freeze-dried at -55°C to obtain a Zylon aerogel nascent fiber.

[0110] (4) Preparation of polymer fiber-based aerogel fiber: The Zylon aerogel nascent fiber prepared in step (3) was high-temperature heat-treated at 550°C for 30 min under nitrogen to obtain a Zylon aerogel fiber, thereby obtaining a polymer fiber-based aerogel fiber.

[0111] Through the above steps, the specific performance of the polymer fiber-based aerogel fiber obtained in the present embodiment is shown in Table 1.

[0112] Example 4

[0113] The present embodiment provides a method for preparing a polymer fiber-based aerogel fiber, and the specific steps include:

[0114] (1) Preparation of nanofiber dispersion: 5 g of Kevlar pulp was weighed and added to 45 g of trifluoroacetic acid, and stirred at 70°C at 1500 rpm for 4 days until a uniform Kevlar nanofiber dispersion was formed, wherein the mass fraction of Kevlar nanofiber was 10%;

[0115] (2) Preparation of the gel fiber of Kevlar nanofiber: 65 g of trifluoroacetic acid, 25 g of water, and 10 g of gluconolactone were mixed to obtain a proton absorber, and the obtained Kevlar nanofiber dispersion was extruded by a wet spinning method at an extrusion speed of 200 μL / min to obtain a Kevlar nanofiber gel fiber by using a spinning needle with a diameter of 500 μm;

[0116] (3) Preparation of Kevlar aerogel nascent fiber: the gel fiber of Kevlar nanofiber obtained in step (2) was aged for 4 days, and was replaced with water for 6 times at an interval of 5 h each time, and finally dried at normal pressure to obtain Kevlar aerogel nascent fiber;

[0117] (4) Preparation of polymer fiber-based aerogel fiber: the Kevlar aerogel nascent fiber prepared in step (3) was high-temperature treated at 450℃ for 10 min under carbon dioxide to obtain Kevlar aerogel fiber.

[0118] After the above steps, the specific properties of the polymer fiber-based aerogel fiber obtained in this embodiment are shown in Table 1.

[0119] The specific properties are shown in Table 1.

[0120] Example 5

[0121] This embodiment provides a preparation method of polymer fiber-based aerogel fiber, and the specific steps include:

[0122] (1) Preparation of nanofiber dispersion: 4 g of M5 short fiber was weighed and added to 96 g of sulfuric acid, and stirred at 95℃ and 1000 rpm for 6 days until a uniform M5 nanofiber dispersion was formed, wherein the mass fraction of M5 nanofiber was 4%;

[0123] (2) Preparation of M5 nanofiber gel fiber: 45 g of sulfuric acid, 25 g of water, and 35 g of ethyl acetate were mixed to obtain a proton absorber, and the obtained M5 nanofiber dispersion was extruded by a wet spinning method at an extrusion speed of 100 μL / min to obtain an M5 nanofiber gel fiber by using a spinning needle with a diameter of 400 μm;

[0124] (3) M5 aerogel nascent fiber: the M5 nanofiber gel fiber was aged for 2 days, and was replaced with dioxane for 8 times at an interval of 3 h each time, and finally freeze-dried to obtain M5 aerogel nascent fiber;

[0125] (4) Preparation of polymer fiber-based aerogel fiber: the M5 aerogel nascent fiber prepared in step (3) was high-temperature treated at 500℃ for 15 min under nitrogen to obtain M5 aerogel fiber.

[0126] As Figure 4 The adsorption amount-relative pressure curve of the high-performance polymer aerogel fiber material prepared by the above steps is shown in the figure, and it can be seen from the figure that the aerogel fiber appears a typical IV type adsorption-desorption curve, which proves that the aerogel has a large amount of mesoporous structure.

[0127] Referring to Figure 5 The infrared spectrum of the M5 aerogel fiber prepared in this embodiment after high-temperature hot table is shown in the figure, and it can be seen from the figure that the M5 aerogel fiber shows excellent heat insulation performance and has potential application in the field of heat preservation and insulation.

[0128] The specific performance is shown in Table 1.

[0129] Example 6

[0130] The embodiment provides a preparation method of a polymer fiber-based aerogel fiber, and the specific steps include:

[0131] (1) Preparation of nanofiber dispersion liquid: 8g Technora yarn is weighed and added to 92g trichloroacetic acid, and stirred at 85°C and 1200rpm for 5 days until a uniform Technora nanofiber dispersion liquid is formed, wherein the mass fraction of Technora nanofiber is 8%;

[0132] (2) Preparation of Technora nanofiber gel fiber: 35g trichloroacetic acid, 35g water and 30g ethyl acetate are mixed uniformly to obtain a proton absorber, and the obtained Technora nanofiber dispersion liquid is extruded by a wet spinning method to obtain a Technora nanofiber gel fiber, with an extrusion speed of 3000μL / min and a spinning needle diameter of 500μm;

[0133] (3) Preparation of Technora aerogel primary fiber: the Technora nanofiber gel fiber obtained in step (2) is aged for 4 days, and is replaced with ethanol for 6 times with an interval of 6h. Finally, the Technora aerogel primary fiber is obtained by supercritical drying;

[0134] (4) Preparation of Technora aerogel fiber: the Technora aerogel primary fiber obtained in step (3) is high-temperature treated at 350°C for 45min under argon to obtain a Technora aerogel fiber.

[0135] Through the above steps, the specific performance of the aerogel fiber obtained in this embodiment is shown in Table 1. It can be seen from Table 1 that the thermal conductivity of Example 6 is as low as 34.6mw / m·K, and obviously, the polymer aerogel fiber prepared by the technical scheme of the application has very excellent thermal conductivity.

[0136] Example 7

[0137] The embodiment provides a preparation method of a polymer fiber-based aerogel fiber, and specific steps comprise the following steps:

[0138] (1) Preparation of nanofiber dispersion liquid: 6 g of F3 fiber is weighed and added into 94 g of methane sulfonic acid, and stirring is carried out at 95 DEG C and 1300 rpm for 7 days until a uniform F3 nanofiber dispersion liquid is formed, wherein the mass fraction of the F3 nanofiber is 6 %;

[0139] (2) Preparation of gel fiber of F3 nanofiber: 45 g of sulfuric acid, 25 g of water and 35 g of ethyl butyrate are uniformly mixed to obtain a proton absorbent, and the obtained F3 nanofiber dispersion liquid is extruded by a wet spinning method to obtain a gel fiber of F3 nanofiber at an extrusion speed of 180 μL / min and a spinning needle head with a diameter of 300 μm;

[0140] (3) Preparation of F3 aerogel nascent fiber: the gel fiber of F3 nanofiber obtained in step (2) is aged for 1 day, and is replaced with acetone for 6 times at an interval of 5 h. Finally, supercritical drying is carried out to obtain the F3 aerogel nascent fiber.

[0141] (4) Preparation of F3 aerogel fiber: the F3 aerogel nascent fiber obtained in step (3) is high-temperature treated at 300 DEG C for 15 min under argon to obtain the F3 aerogel fiber.

[0142] Other performance parameters of the high-performance polymer aerogel fiber prepared in the embodiment are shown in Table 1.

[0143] Example 8

[0144] The embodiment provides a preparation method of a polymer fiber-based aerogel fiber, and specific steps comprise the following steps:

[0145] (1) Preparation of nanofiber dispersion liquid: 20 g of Nomex cloth is weighed and added into 80 g of nitric acid, and stirring is carried out at 95 DEG C and 1000 rpm for 6 days until a uniform Nomex nanofiber dispersion liquid is formed, wherein the mass fraction of the Nomex nanofiber is 20 %;

[0146] (2) Preparation of gel fiber of Nomex nanofiber: 50 g of nitric acid, 20 g of water and 30 g of ethyl formate are uniformly mixed to obtain a proton absorbent, and the obtained Nomex nanofiber dispersion liquid is extruded by a wet spinning method to obtain a gel fiber of Nomex nanofiber at an extrusion speed of 100 μL / min and a spinning needle head with a diameter of 400 μm;

[0147] (3) Preparation of Nomex aerogel nascent fiber: the gel fiber of Nomex nanofiber obtained in step (2) is aged for 1 day, and is replaced with acetone for 6 times with an interval of 5 h each time to obtain wet gel fiber of Nomex nanofiber, and finally supercritical drying is used to obtain Nomex aerogel nascent fiber;

[0148] (4) Preparation of Nomex aerogel fiber: the Nomex aerogel nascent fiber obtained in step (3) is high-temperature heat-treated at 300°C for 15 min under nitrogen to obtain Nomex aerogel fiber.

[0149] Other performance parameters of the high-performance polymer aerogel fiber prepared in this example are shown in Table 1.

[0150] Example 9

[0151] This example provides a preparation method of a polymer fiber-based aerogel fiber, and the specific steps include:

[0152] (1) Preparation of nanofiber dispersion liquid: 10 g of Terlon short fiber is weighed and added to 90 g of sulfuric acid, and stirred at 60°C and 1000 rpm for 5 days until a uniform Terlon nanofiber dispersion liquid is formed, wherein the mass fraction of Terlon nanofiber is 10%;

[0153] (2) Preparation of Terlon nanofiber gel fiber: 45 g of sulfuric acid, 25 g of water and 35 g of ethyl formate are mixed uniformly to obtain a proton absorber, and the Terlon nanofiber dispersion liquid obtained above is extruded by a wet spinning method to obtain a Terlon nanofiber gel fiber with an extrusion speed of 500 μL / min and a spinning needle diameter of 300 μm;

[0154] (3) Preparation of Terlon aerogel nascent fiber: the gel fiber of Terlon nanofiber obtained in step (2) is aged for 4 days, and is replaced with ethanol for 6 times with an interval of 5 h each time to obtain wet gel fiber, and finally supercritical drying is used to obtain Terlon aerogel nascent fiber;

[0155] (4) Preparation of Terlon aerogel fiber: the Terlon aerogel nascent fiber obtained in step (3) is high-temperature heat-treated at 400°C for 5 min under nitrogen to obtain Terlon aerogel fiber.

[0156] Other performance parameters of the high-performance polymer aerogel fiber prepared in this example are shown in Table 1.

[0157] Example 10

[0158] This example provides a preparation method of a polymer fiber-based aerogel fiber, and the specific steps include:

[0159] (1) Preparation of nanofiber dispersion liquid: 5 g of Armors short fibers was weighed and added to 95 g of methane sulfonic acid, and stirred at 100 ℃ and 1400 rpm for 5 days until a uniform Armors nanofiber dispersion liquid was formed, wherein the mass fraction of the Armors nanofiber was 5%;

[0160] (2) Preparation of gel fiber of Armors nanofiber: 65 g of methane sulfonic acid, 15 g of water and 20 g of gluconolactone were mixed uniformly to obtain a proton absorber, and the obtained Armors nanofiber dispersion liquid was spun in the proton absorber by wet spinning, and an Armors nanofiber gel fiber was obtained by extrusion at an extrusion speed of 100 μL / min and a spinning needle with a diameter of 400 μm;

[0161] (3) Preparation of Armors aerogel nascent fiber: the Armors nanofiber gel fiber obtained in step (2) was aged for 2 days, and was replaced with tert-butyl alcohol for 8 times with an interval of 3 h each time to obtain a wet gel fiber, and finally freeze-dried to obtain an Armors aerogel nascent fiber;

[0162] (4) Preparation of Armors aerogel fiber: the Armors aerogel nascent fiber obtained in step (3) was high-temperature heat-treated at 500 ℃ for 15 min under hydrogen to obtain an Armors aerogel fiber.

[0163] Referring to Figure 6 The scanning electron microscope image of the Armors aerogel fiber prepared in this embodiment is shown in the figure, and it can be seen from the figure that the obtained aerogel fiber has a porous nanostructure.

[0164] The other performance parameters of the high-performance polymer aerogel fiber prepared in this embodiment are shown in Table 1.

[0165] Example 11

[0166] The embodiment provides a preparation method of a polymer fiber-based aerogel fiber, and the specific steps include:

[0167] (1) Preparation of nanofiber dispersion liquid: 12 g of SVM fibers was weighed and added to 88 g of methane sulfonic acid and trifluoroacetic acid (mass ratio 1:1), and stirred at 60 ℃ and 800 rpm for 3 days until a uniform SVM nanofiber dispersion liquid was formed, wherein the mass fraction of the SVM nanofiber was 12%;

[0168] (2) Preparation of the gel fiber of the SVM nanofiber: 45 g of methanesulfonic acid, 25 g of ethanol, and 30 g of ethyl acetate were mixed uniformly to obtain a proton absorber, and the SVM nanofiber dispersion obtained above was spun in the proton absorber by wet spinning, to obtain the gel fiber of the SVM nanofiber by extrusion at an extrusion speed of 400 μL / min and with a spinning needle head having a diameter of 300 μm;

[0169] (3) Preparation of the SVM aerogel nascent fiber: the gel fiber of the SVM nanofiber obtained in step (2) was left to stand and age for 6 days, was replaced with phenol 4 times at an interval of 6 h each time, and was finally freeze-dried to obtain the SVM aerogel nascent fiber;

[0170] (4) Preparation of the SVM aerogel fiber: the SVM aerogel nascent fiber obtained in step (3) was high-temperature heat-treated at 500 °C for 5 min under carbon dioxide gas to obtain the SVM aerogel fiber.

[0171] Referring to Figure 7 The scanning electron microscope image of the interface of the SVM aerogel fiber prepared in this embodiment is shown in the figure, and it can be seen from the figure that the aerogel fiber has a good appearance effect. The fracture has a fine neck phenomenon, which effectively resists external stress.

[0172] The other performance parameters of the high-performance polymer aerogel fiber prepared in this embodiment are shown in Table 1.

[0173] Example 12

[0174] This embodiment provides a preparation method of a polymer fiber-based aerogel fiber, and the specific steps include:

[0175] (1) Preparation of the nanofiber dispersion: 15 g of Twaron fiber was weighed and added to 85 g of trifluoroacetic acid, and the mixture was stirred at 100 °C at 600 rpm for 5 days until a uniform Twaron nanofiber dispersion was formed, wherein the mass fraction of the Twaron nanofiber was 15%;

[0176] (2) Preparation of the gel fiber of the Twaron nanofiber: 65 g of trifluoroacetic acid, 15 g of water, and 20 g of ethyl formate were mixed uniformly to obtain a proton absorber, and the Twaron nanofiber dispersion obtained above was spun in the proton absorber by wet spinning, to obtain the gel fiber of the Twaron nanofiber by extrusion at an extrusion speed of 400 μL / min and with a spinning needle head having a diameter of 300 μm;

[0177] (3) Preparation of the Twaron aerogel nascent fiber: the gel fiber of the Twaron nanofiber obtained in step (2) was left to stand and age for 4 days, was replaced with methanol 9 times at an interval of 3 h each time, and was finally supercritically dried to obtain the Twaron aerogel nascent fiber;

[0178] (4) Preparation of Twaron aerogel fiber: the Twaron aerogel nascent fiber obtained in step (3) is high-temperature heat-treated at 400°C for 30 min under argon to obtain a Twaron aerogel fiber.

[0179] The other performance parameters of the high-performance polymer aerogel fiber prepared in this example are shown in Table 1.

[0180] Referring to Table 1, the structure and physical performance parameters of the fiber aerogel fiber obtained in Examples 1-11 of the present application are shown.

[0181] Table 1 Performance parameters of the high-performance polymer aerogel fiber obtained in Examples 1-7

[0182]

[0183]

[0184] In summary, by means of the above technical solutions, the present application provides a preparation method of a high-performance polymer fiber-based aerogel fiber, which has simple preparation process, fewer preparation steps, relatively short preparation period, no need for harmful solvents that are difficult to recover, lower cost, high economic benefit, and conditions for industrial production.

[0185] In addition, the present inventors have also carried out tests with other raw materials, process operations, and process conditions described in the present specification with reference to the foregoing examples, and all have obtained relatively ideal results.

[0186] Although the present application has been described with reference to the illustrative embodiments, it will be understood by those skilled in the art that various other changes, omissions, and / or additions can be made without departing from the spirit and scope of the present application. In addition, many modifications can be made to adapt a particular situation or material to the teachings of the present application without departing from the scope thereof. Therefore, it is intended that the present application not be limited to the disclosed embodiments, but will include all embodiments falling within the scope of the appended claims.

Claims

1. A method for preparing a high-performance polymer fiber-based aerogel fiber, comprising: obtaining a high-performance polymer gel fiber by using a proton absorber in a coagulation bath through gel spinning technology with a high-performance polymer fiber precursor; and obtaining the high-performance polymer fiber-based aerogel fiber after sequentially performing aging-solvent replacement-drying-heat treatment. wherein The high-performance polymer fiber precursor is a homogeneous nanofiber dispersion prepared by solution reaction of a high-performance polymer fiber and a first protonic acid. The polymer in the high-performance polymer fiber includes at least one of polybenzotriazole, poly-p-phenylene benzobisthiazole, poly-p-phenylene benzobisoxazole, poly-p-phenylene terephthalamide, poly-m-phenylene isophthalamide, poly-p-phenylene terephthalamide copolymerized with m-phenylene isophthalamide, or at least one of the above polymers containing a functional substituent. The coagulation bath is obtained by standing a mixed solution of a first solvent, a second protonic acid and the proton absorber. The proton absorber includes at least one of ethyl formate, ethyl acetate, ethyl butyrate and gluconolactone, or a mixture of two or more thereof.

2. The method of making high performance polymeric fiber-based aerogel fibers according to claim 1, wherein, The method specifically comprises the following steps: S1. Preparation of a high-performance polymer fiber precursor: dissolving the high-performance polymer in the first protonic acid to perform protonation reaction to form a homogeneous nanofiber dispersion, which is the high-performance polymer fiber precursor. S2. Preparation of a nanofiber gel fiber: performing wet gel spinning of the high-performance polymer fiber precursor in the coagulation bath by using the proton absorber to obtain the nanofiber gel fiber. S3. Preparation of an aerogel nascent fiber: standing the nanofiber gel fiber to perform aging to obtain a wet gel fiber; and performing drying treatment on the wet gel fiber to obtain the aerogel nascent fiber. S4. Preparation of a high-performance polymer fiber-based aerogel fiber: performing high-temperature heat treatment on the aerogel nascent fiber to obtain the polymer fiber-based aerogel fiber.

3. The method of making high performance polymeric fiber-based aerogel fibers according to claim 1, wherein, The high-performance polymer fiber has at least one of a block, a fiber, paper, pulp, and powder.

4. The method of making high performance polymeric fiber-based aerogel fibers according to claim 1, wherein, The first solvent is at least one of water, methanol, ethanol and acetone, or a mixture of two or more thereof.

5. The method of making high performance polymeric fiber-based aerogel fibers according to claim 1, wherein, The mass ratio of the first solvent: the proton absorber: the second protonic acid is (5-70):(10-25):(20-70).

6. The method of making high-performance polymeric fiber-based aerogel fibers according to claim 1, wherein, The first and second protonic acids are at least one of methane sulfonic acid, sulfuric acid, trifluoroacetic acid, trichloroacetic acid, nitric acid and nitromethane.

7. The method of making high performance polymeric fiber-based aerogel fibers according to claim 6, wherein, The first and second protonic acids are at least one of trifluoroacetic acid, methane sulfonic acid and sulfuric acid.

8. The method of making high-performance polymeric fiber-based aerogel fibers according to claim 1, wherein, The mass fraction of the high-performance polymer fiber precursor is 0.01-25wt%.

9. The method of making high-performance polymeric fiber-based aerogel fibers according to claim 1, wherein, The mass fraction of the high-performance polymer fiber precursor is 0.1-10wt%.

10. The method of making high-performance polymeric fiber-based aerogel fibers according to claim 1, wherein, The mass ratio of the high-performance polymer fiber to the first protonic acid is 1:4-1:

500.

11. The method of making high-performance polymeric fiber-based aerogel fibers according to claim 10, wherein, The dissolution temperature of the high-performance polymer fiber in the first protonic acid is 25-120℃.

12. The method of making high-performance polymeric fiber-based aerogel fibers according to claim 10, wherein, The dissolution temperature of the high-performance polymer fiber in the first protonic acid is 40-80℃.

13. The process for preparing high performance polymeric fiber-based aerogel fibers according to claim 1, characterized in that, The reaction time is 10 hours to 7 days.

14. The process for preparing high performance polymeric fiber-based aerogel fibers according to claim 1, characterized in that, The reaction time is 1 day to 3 days.

15. The process for preparing high performance polymeric fiber based aerogel fibers as claimed in claim 1, wherein, The aging-solvent replacement-drying-heat treatment method comprises the following steps: obtaining high-performance polymer gel fibers by regulating wet gel spinning technology with the proton absorber in a coagulation bath, standing, aging the high-performance polymer gel fibers, replacing the solvent, obtaining nanofiber wet gel fibers, drying the nanofiber wet gel fibers, and then performing high-temperature heat treatment in a selected gas atmosphere to obtain high-performance polymer fiber-based aerogel fibers. The drying is gas-liquid exchange drying.

16. The method of making high-performance polymeric fiber-based aerogel fibers according to claim 15, wherein, The high-temperature heat treatment temperature is 350-630℃, and the time is 1 minute to 1 hour.

17. The method of making high-performance polymeric fiber-based aerogel fibers according to claim 15, wherein, The standing time is 3-5 days.

18. The process for preparing high performance polymeric fiber-based aerogel fibers according to claim 15, characterized in that, The aging time is 5-48 hours.

19. The process for preparing high performance polymeric fiber-based aerogel fibers according to claim 15, characterized in that, The aging time is 10-24 hours.

20. The method of producing high-performance polymeric fiber-based aerogel fibers of claim 15, wherein, The solvent replacement is replaced at least 5 times with a second solvent, and the interval time is at least 3-5 hours each time.

21. The method of making high-performance polymeric fiber-based aerogel fibers according to claim 20, wherein, The second solvent comprises at least one of water, ethanol, tert-butyl alcohol, dioxane, phenol, and acetone.

22. The method of manufacturing high-performance polymeric fiber-based aerogel fibers of claim 15, wherein, The selected gas atmosphere comprises an atmosphere formed by at least one of nitrogen, argon, air, helium, and carbon dioxide.

23. A high-performance polymer fiber-based aerogel fiber prepared by the preparation method of any one of claims 1-22.

24. The high-performance polymer fiber-based aerogel fiber of claim 23, wherein, The high-performance polymer fiber-based aerogel fiber is assembled by nanofibers and simultaneously forms a hierarchical pore structure composed of micropores with a pore size of less than 2 nm, mesopores with a pore size of 2-50 nm, and macropores with a pore size of > 50 μm; the density of the high-performance polymer fiber-based aerogel fiber is 0.1-200 mg / cm 3 , the porosity is 60%-99.99%, the specific surface area is 1-1000 m 2 / g, the tensile strength is 0.1-40 MPa, and the thermal conductivity is 10-100 mw / (m·k).

25. Use of the high-performance polymer fiber-based aerogel fiber of claim 23 or 24 in the fields of personal clothing thermal management, composite materials, smart wearable, fiber batts, thermal insulation under extreme conditions, and filtration materials.

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