A hollow aerogel fiber imitating polar bear hair, a preparation method thereof, and application thereof
Patent Information
- Application Number
- CN202611038254.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-07-13
- Publication Date
- 2026-09-29
AI Technical Summary
但纯粘胶基气凝胶纤维的力学强度偏低，不仅限制了其在高端隔热场景的应用，而且制备中空气凝胶纤维时容易发生结构坍塌等问题，影响其隔热效果的持久性
[0028]本申请提供了一种仿北极熊毛的中空气凝胶纤维的制备方法，包括以下步骤：以水为内轴溶液，以粘胶纺丝液为外轴溶液，采用同轴湿法纺丝装置进行纺丝，在凝固浴中进行牵伸后得到湿纤维；将所述湿纤维依次在第一溶剂中进行第一置换，在第二溶剂中进行第二置换，干燥后得到中空气凝胶纤维；所述第一溶剂和第二溶剂独立地为水和有机溶剂的混合物，所述第二溶剂中有机溶剂的浓度大于第一溶剂中有机溶剂的浓度。本申请采用同轴湿法纺丝装置将粘胶纤维纺成湿纤维，然后依次在有机溶剂浓度逐渐升高的第一溶剂和第二溶剂中进行多级置换，一方面能够保证纤维内部形成微孔结构，避免溶剂交换过于剧烈产生大孔结构，降低隔热性能；另一方面能够保证内部溶剂缓慢置换，能够有效避免孔隙坍塌，避免置换过程中纤维内部骨架受损。实验结果表明，本申请提供的方法制备得到的中空气凝胶纤维骨架结构完整，内部孔结构分布均匀，孔径均小于1微米，具有良好的力学性能、阻燃性能和隔热性能。
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Abstract
Description
Technical Field
[0001] This application relates to the field of fiber manufacturing technology, and in particular to a medium-air gel fiber that mimics polar bear fur, its preparation method, and its application. Background Technology
[0002] The demand for high-efficiency thermal insulation materials is increasingly urgent in fields such as aerospace, building energy conservation, and high-end clothing. In particular, fiber materials that combine lightweight, flexibility, and flame retardancy have become key to solving thermal insulation and safety issues in extreme environments or everyday scenarios. Aerogel fibers, with their extremely low thermal conductivity and unique porous structure, have become a research hotspot in the field of thermal insulation materials. The excellent thermal insulation performance exhibited by the hollow structure of polar bear fur in the biological world has provided important inspiration for the structural design of aerogel fibers.
[0003] Aerogel is a solid nanomaterial with a three-dimensional network structure. It has ultra-high porosity, large specific surface area, ultra-low density, and excellent mechanical properties and wearability. It has important application value in many fields such as textiles, environment, energy conversion and storage, thermal protection, infrared stealth, and electromagnetic shielding. Applying the excellent properties of aerogel and its flexible preparation methods to the manufacture of hollow fibers can trap a large amount of air and effectively suppress heat conduction, heat convection and heat radiation.
[0004] Viscose fiber, as a regenerated cellulose fiber, has advantages such as good biocompatibility, excellent spinnability, and renewable source, making it an ideal matrix for preparing high-performance composite fibers. However, the low mechanical strength of pure viscose-based aerogel fibers not only limits their application in high-end thermal insulation scenarios, but also makes them prone to structural collapse during the preparation of aerogel fibers, affecting the durability of their thermal insulation effect. Summary of the Invention
[0005] In view of this, this application provides a polar bear fur-like air gel fiber, its preparation method and its application. The air gel fiber prepared by this application has a complete skeleton structure, a uniform distribution of internal pore structure, and good mechanical properties, thermal insulation properties and flame retardant properties.
[0006] This application provides a method for preparing air-gel fibers that mimic polar bear fur, comprising the following steps:
[0007] Using water as the inner axis solution and viscose spinning solution as the outer axis solution, spinning is carried out using a coaxial wet spinning device, and wet fibers are obtained after being drawn in a coagulation bath.
[0008] The wet fibers are sequentially subjected to a first displacement in a first solvent and a second displacement in a second solvent, and then dried to obtain air gel fibers.
[0009] The first solvent and the second solvent are independently mixtures of water and organic solvents, wherein the concentration of the organic solvent in the second solvent is greater than the concentration of the organic solvent in the first solvent.
[0010] In some specific implementations, the method further includes: sequentially performing a third displacement on the wet fibers obtained by a second displacement in a second solvent, and a fourth displacement on the wet fibers obtained by a second displacement in a third solvent, and a fourth displacement in a fourth solvent;
[0011] The third and fourth solvents are independently mixtures of water and organic solvents, wherein the concentration of the organic solvent in the fourth solvent is greater than the concentration of the organic solvent in the third solvent, and the concentration of the organic solvent in the third solvent is greater than the concentration of the organic solvent in the second solvent.
[0012] In some specific implementations, the concentration of the organic solvent in the first solvent is 20 vol% to 30 vol%.
[0013] The concentration of the organic solvent in the second solvent is 45 vol% to 55 vol%.
[0014] The concentration of the organic solvent in the third solvent is 70 vol% to 80 vol%.
[0015] The concentration of the organic solvent in the fourth solvent is 90 vol% to 100 vol%.
[0016] In some specific implementations, the organic solvent is selected from one or more of tert-butanol, ethanol, and acetone.
[0017] In some specific implementations, the viscose spinning solution includes cellulose xanthate, inorganic nano-additives, silane coupling agent, sodium hydroxide, and water;
[0018] The concentration of cellulose xanthate in the viscose spinning solution is 5wt%~10wt%;
[0019] The concentration of inorganic nano-additives in the viscose spinning solution is 0.1wt%~1wt%;
[0020] The concentration of silane coupling agent in the viscose spinning solution is 0.2wt%~0.8wt%.
[0021] In some specific implementations, the inorganic nano-additives include one or more of nano-montmorillonite, nano-calcium carbonate, and nano-kaolinite;
[0022] The silane coupling agent includes one or more of bis(triethoxysilyl)ethane, γ-methacryloxypropyltrimethoxysilane, and vinyltrimethoxysilane.
[0023] In some specific implementations, the inner needle diameter of the coaxial wet spinning device is 0.3mm~0.5mm, the outer needle diameter is 0.5mm~1mm, and the extrusion rate is 100μL / min~500μL / min.
[0024] In some specific implementations, the coagulation bath includes sulfuric acid, sodium sulfate, and water;
[0025] The mass ratio of sulfuric acid, sodium sulfate and water is 5~10:5~10:80~90.
[0026] This application also provides a micro-air gel fiber that mimics polar bear fur, prepared by the preparation method described in the above technical solution.
[0027] This application also provides the application of the microfiber-like polar bear fur prepared by the preparation method described above, or the microfiber-like polar bear fur prepared by the above-described technical solution, in the preparation of vehicle interior, clothing, or furniture fabrics.
[0028] This application provides a method for preparing polar bear fur-like air gel fiber, comprising the following steps: using water as the inner axis solution and viscose spinning solution as the outer axis solution, spinning is performed using a coaxial wet spinning device, followed by stretching in a coagulation bath to obtain wet fibers; the wet fibers are then subjected to a first displacement in a first solvent and a second displacement in a second solvent, followed by drying to obtain air gel fiber; the first and second solvents are independently mixtures of water and organic solvents, with the concentration of organic solvent in the second solvent being greater than that in the first solvent. This application uses a coaxial wet spinning device to spin viscose fiber into wet fibers, and then performs multi-stage displacement in a first and second solvent with gradually increasing organic solvent concentrations. This ensures the formation of a microporous structure within the fiber, avoiding excessively vigorous solvent exchange that could lead to macroporous structures and reduced thermal insulation performance; it also ensures slow internal solvent displacement, effectively preventing pore collapse and damage to the fiber's internal skeleton during the displacement process. Experimental results show that the air gel fiber prepared by the method provided in this application has a complete skeleton structure, uniform internal pore distribution, and pore sizes all less than 1 micrometer, exhibiting good mechanical properties, flame retardant properties, and thermal insulation properties. Attached Figure Description
[0029] Figure 1 A scanning electron microscope image of the hollow viscose aerogel fiber prepared in Example 1 of this application;
[0030] Figure 2 This is a scanning electron microscope image of the surface of the hollow viscose aerogel fiber prepared in Example 1 of this application;
[0031] Figure 3The BET adsorption curve of the hollow viscose aerogel fiber prepared in Example 1 of this application;
[0032] Figure 4 The tensile strength curve of the hollow viscose aerogel fiber prepared in Example 1 of this application;
[0033] Figure 5 The heat release curve of the hollow viscose aerogel fiber prepared in Example 1 of this application;
[0034] Figure 6 This is a high-temperature thermal infrared image of the hollow viscose aerogel fiber prepared in Example 1 of this application;
[0035] Figure 7 This is a low-temperature thermal infrared image of the hollow viscose aerogel fiber prepared in Example 1 of this application;
[0036] Figure 8 This is a scanning electron microscope image of the surface of the hollow viscose aerogel fiber prepared in Comparative Example 1 of this application. Detailed Implementation
[0037] It should be understood that the expression “one or more of…” individually includes each of the objects described after the expression, as well as various different combinations of two or more of the described objects, unless otherwise understood from the context and usage. The expression “and / or” combined with three or more described objects should be understood to have the same meaning, unless otherwise understood from the context.
[0038] The terms “including,” “having,” or “containing,” including the use of their grammatical synonyms, should generally be understood as open-ended and non-restrictive, for example, not excluding other unstated elements or steps, unless otherwise specifically stated or understood from the context.
[0039] It should be understood that the order of steps or the sequence of actions is not important as long as this application remains operational. Furthermore, two or more steps or actions can be performed simultaneously.
[0040] The use of any and all instances or exemplary language such as “e.g.” or “including” herein is merely intended to better illustrate the application and does not constitute a limitation on the scope of the application unless the claims are made. No language in this specification should be construed as indicating that any unclaimed element is essential to the practice of this application.
[0041] Furthermore, the numerical ranges and parameters used to define this application are approximate values, and the relevant values in the specific embodiments have been presented as precisely as possible. However, any numerical value inevitably contains standard deviations due to individual test methods. Therefore, unless otherwise explicitly stated, it should be understood that all ranges, quantities, values, and percentages used in this disclosure are modified with the word "approximately." Here, "approximately" generally means that the actual value is within plus or minus 10%, 5%, 1%, or 0.5% of a specific value or range.
[0042] This application provides a method for preparing air-gel fibers that mimic polar bear fur, comprising the following steps:
[0043] Using water as the inner axis solution and viscose spinning solution as the outer axis solution, spinning is carried out using a coaxial wet spinning device, and wet fibers are obtained after being drawn in a coagulation bath.
[0044] The wet fibers are sequentially subjected to a first displacement in a first solvent and a second displacement in a second solvent, and then dried to obtain air gel fibers.
[0045] The first solvent and the second solvent are independently mixtures of water and organic solvents, wherein the concentration of the organic solvent in the second solvent is greater than the concentration of the organic solvent in the first solvent.
[0046] This application uses water as the inner axis solution and viscose spinning solution as the outer axis solution, employing a coaxial wet spinning apparatus for spinning. This application does not impose any special limitations on the coaxial wet spinning apparatus; any coaxial wet spinning apparatus commonly used by those skilled in the art will suffice. In some specific implementations, the inner needle diameter of the coaxial wet spinning apparatus is 0.3mm~0.5mm, preferably 0.35mm~0.45mm; the outer needle diameter is 0.5mm~1mm, preferably 0.6mm~0.8mm; and the extrusion rate is 100μL / min~500μL / min, preferably 200μL / min~400μL / min.
[0047] This application uses viscose spinning solution as the outer axis solution, wherein the viscose spinning solution includes cellulose xanthate, inorganic nano-additives, silane coupling agent, sodium hydroxide and water.
[0048] The viscose spinning solution provided in this application includes cellulose xanthate, which is the main component in the formation of viscose fibers. This application does not impose any particular limitation on the cellulose xanthate; it can be a commercially available product used for preparing viscose fibers, or it can be prepared by the following method: soaking cellulose powder in a sodium hydroxide solution, removing the solvent, and then xanthating it under the action of carbon disulfide to obtain cellulose xanthate. In some specific implementations, the cellulose xanthate is prepared by the following method: soaking cellulose in a 18%~20% sodium hydroxide solution for 20min~30min, pressing to remove the solvent, allowing it to stand for 12h~24h, transferring it to a closed xanthation reactor, adding carbon disulfide dropwise, xanthating under vacuum stirring for 1h~3h, and then removing the solvent to obtain cellulose xanthate. In some specific implementations, the mass ratio of cellulose to carbon disulfide is 1:0.3~0.5.
[0049] In some specific implementations, the concentration of cellulose xanthate in the viscose spinning solution is 5wt%~10wt%, preferably 7wt%~9wt%.
[0050] The viscose spinning solution provided in this application includes inorganic nano-additives and silane coupling agents. The silane coupling agent and the inorganic nano-additives, especially nano-montmorillonite, have a synergistic effect, simultaneously achieving molecular chain reinforcement, optimized nanofiller dispersion, and improved flame retardant properties. In some specific implementations, the inorganic nano-additives include, but are not limited to, nano-montmorillonite, nano-calcium carbonate, and nano-kaolin, and may be one or more of these, preferably nano-montmorillonite. In some specific implementations, the silane coupling agent includes, but is not limited to, bis(triethoxysilyl)ethane, γ-methacryloyloxypropyltrimethoxysilane, and vinyltrimethoxysilane, and may be one or more of these. When the silane coupling agent is a combination of multiple substances, this application does not impose any special restrictions on the proportion of each specific substance. In some specific implementations, the concentration of the inorganic nano-additives in the viscose spinning solution is 0.1wt%~1wt%, preferably 0.2wt%~0.8wt%, and more preferably 0.4wt%~0.6wt%. In some specific implementations, the concentration of silane coupling agent in the viscose spinning solution is 0.2wt%~0.8wt%, preferably 0.3wt%~0.7wt%, and more preferably 0.4wt%~0.6wt%.
[0051] The viscose spinning solution provided in this application comprises sodium hydroxide and water, which is used to dissolve cellulose xanthate to form a viscose solution. In some specific implementations, the sodium hydroxide and water form a solution with a mass concentration of 4% to 6% and a pH value of 11 to 12.
[0052] This application uses water as the inner axis solution and viscose spinning solution as the outer axis solution, employing a coaxial wet spinning device for spinning. Wet fibers are obtained after drawing in a coagulation bath. This application does not impose special limitations on the specific spinning parameters; they can be selected according to the needs of those skilled in the art. In some specific implementations, the coagulation bath includes sulfuric acid, sodium sulfate, and water. In some specific implementations, the mass ratio of sulfuric acid, sodium sulfate, and water is 5~10:5~10:80~90, preferably 6~8:6~8:82~88. In some specific implementations, the drawing ratio is 1~3 times, preferably 1.5~2.5 times.
[0053] After obtaining the wet fibers, they are subjected to a stepwise displacement process in a solvent. During this process, the solvent concentration increases sequentially. This ensures the formation of a microporous structure within the fibers, preventing excessively rapid solvent exchange that could create macroporous structures and reduce insulation performance. Furthermore, it ensures slow solvent displacement, effectively preventing pore collapse and damage to the fiber's internal framework. In some specific implementations, after obtaining the wet fibers, they are subjected to a first displacement in a first solvent and a second displacement in a second solvent. The first and second solvents are independently mixtures of water and an organic solvent, with the concentration of the organic solvent in the second solvent being higher than that in the first solvent. In some further implementations, the wet fibers obtained from the second displacement in the second solvent are subjected to a third displacement in a third solvent and a fourth displacement in a fourth solvent. The third and fourth solvents are independently mixtures of water and an organic solvent, with the concentration of the organic solvent in the fourth solvent being higher than that in the third solvent, and the concentration of the organic solvent in the third solvent being higher than that in the second solvent. In some specific implementations, the concentration of the organic solvent in the first solvent is 20 vol% to 30 vol%; the concentration of the organic solvent in the second solvent is 45 vol% to 55 vol%; the concentration of the organic solvent in the third solvent is 70 vol% to 80 vol%; and the concentration of the organic solvent in the fourth solvent is 90 vol% to 100 vol%. In some specific implementations, the organic solvent in the solvents includes, but is not limited to, tert-butanol, ethanol, and acetone, and can be one or more of these, preferably tert-butanol. In some specific implementations, the temperatures for the first, second, third, and fourth substitutions are independently 20°C to 40°C, preferably 25°C to 35°C; and the times are independently 5 h to 20 h, preferably 10 h to 15 h.
[0054] After solvent replacement, the resulting fibers are dried to obtain air gel fibers. In some specific implementations, the drying is preferably supercritical CO2 drying. In some specific implementations, the supercritical CO2 drying temperature is 30℃~50℃, preferably 35℃~45℃; the pressure is 10MPa~20MPa, preferably 12MPa~18MPa; and the time is 1h~5h, preferably 2h~4h.
[0055] This application also provides a polar bear fur-like air gel fiber prepared by the preparation method described above, which has a complete fiber skeleton structure and a uniformly distributed internal pore structure, with pore diameters all less than 1 micrometer.
[0056] The air gel fiber provided in this application has excellent mechanical properties, with a fiber breaking strength of over 20 MPa and a breaking elongation of over 16%.
[0057] The air gel fiber provided in this application has excellent flame retardant properties, and its peak heat release rate (pHRR) can be reduced by 60%.
[0058] The air-gel fiber provided in this application has excellent thermal insulation properties at both high and low temperatures.
[0059] Based on the above properties, the polar bear fur-like air-gel fiber provided in this application can be used to prepare vehicle interiors, clothing or furniture fabrics, etc., and has good mechanical properties, flame retardant properties and heat insulation properties.
[0060] This application provides a method for preparing centrifugal gel fibers that mimic polar bear fur, comprising the following steps: using water as the inner axis solution and viscose spinning solution as the outer axis solution, spinning is performed using a coaxial wet spinning device, followed by stretching in a coagulation bath to obtain wet fibers; the wet fibers are then subjected to a first displacement in a first solvent and a second displacement in a second solvent, followed by drying to obtain centrifugal gel fibers; the first and second solvents are independently mixtures of water and organic solvents, with the concentration of the organic solvent in the second solvent being greater than that in the first solvent. This application uses a coaxial wet spinning device to spin viscose fibers into wet fibers, and then performs multi-stage displacement in a first and second solvent with gradually increasing organic solvent concentrations. This ensures the formation of a microporous structure within the fiber, avoiding excessively vigorous solvent exchange that could create a macroporous structure and reduce thermal insulation performance; it also ensures slow internal solvent displacement, effectively preventing pore collapse and damage to the fiber's internal skeleton during the displacement process. Experimental results show that the centrifugal gel fibers prepared by the method provided in this application have a complete skeleton structure, uniform internal pore distribution, and pore sizes all less than 1 micrometer, exhibiting good mechanical and thermal insulation properties.
[0061] The technical solution of the present invention will be clearly and completely described below with reference to embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. The scope of protection of the present invention is not limited by the following embodiments.
[0062] In the following examples, the adhesive is cellulose xanthate, which can be purchased commercially or prepared according to the following methods:
[0063] Cellulose powder is soaked in a sodium hydroxide solution with a mass fraction of 18%~20% for 20min~30min, then pressed to remove the solvent, and allowed to stand for 12~24h. Then it is transferred to a closed xanthation kettle, and carbon disulfide is added dropwise (the mass ratio of cellulose to carbon disulfide is 1:0.3~0.5). The mixture is stirred under vacuum for 1~3h to remove the solvent and obtain cellulose xanthate.
[0064] Example 1
[0065] Viscose was dissolved in a 5% sodium hydroxide aqueous solution with a pH of approximately 12. Nano-montmorillonite and bis(triethoxysilyl)ethane were added, and the solution was ultrasonically stirred to obtain a viscose spinning solution. The viscose spinning solution contained 8 wt% viscose, 0.5 wt% nano-montmorillonite, and 0.6 wt% bis(triethoxysilyl)ethane.
[0066] Using water as the inner spindle solution and the above-mentioned viscose spinning solution as the outer spindle solution, a coaxial wet spinning device with an inner needle hole diameter of 0.4 mm and an outer needle hole diameter of 0.8 mm was used for spinning. The extrusion rate of the spinning was 300 μL / min. The fibers were extruded into a coagulation bath composed of sulfuric acid, sodium sulfate and water in a mass ratio of 5:5:90 for 1.5 times stretching treatment to obtain wet fibers.
[0067] The wet fibers were sequentially immersed in aqueous solutions of tert-butanol with concentrations of 25 vol%, 50 vol%, 75 vol%, and 100 vol% for displacement at each stage, with a temperature of 35°C and a time of 12 h. Then, supercritical CO2 drying was performed at a supercritical temperature of 40°C, a pressure of 15 MPa, and a time of 3 h to obtain hollow viscose aerogel fibers that mimic polar bear fur.
[0068] Electron microscopy was performed on the hollow viscose aerogel fibers prepared in Example 1. The results are shown in [reference needed]. Figure 1 and Figure 2 , Figure 1 This is a scanning electron microscope image of the hollow viscose aerogel fibers prepared in Example 1 of this application. Figure 2This is a scanning electron microscope (SEM) image of the surface of the hollow viscose aerogel fiber prepared in Example 1 of this application. Figure 1 and Figure 2 It is known that the hollow viscose aerogel fiber skeleton structure prepared by the preparation method provided in this application is complete, the internal pore structure is uniformly distributed, and the pore size is less than 1 micrometer.
[0069] The hollow viscose aerogel fibers were subjected to BET adsorption experiments according to the low-temperature nitrogen adsorption-desorption BET test method. The test temperature was room temperature, the degassing temperature was 120℃, and the degassing time was 8 hours. Results are shown below. Figure 3 , Figure 3 The BET adsorption curve of the hollow viscose aerogel fiber prepared in Example 1 of this application is shown below. Figure 3 It can be seen that the internal pore structure of aerogel fibers exhibits typical microporous structure characteristics.
[0070] The hollow viscose aerogel fiber was subjected to a tensile strength test using an electronic universal testing machine. The test length was 20 mm, and the tensile rate was 20 mm / min. See the results below. Figure 4 , Figure 4 The tensile strength curve of the hollow viscose aerogel fiber prepared in Example 1 of this application is obtained from... Figure 4 It can be seen that the fiber breaking strength can reach 23.2 MPa and the breaking elongation reaches 16.1%, exhibiting excellent mechanical properties.
[0071] The heat release experiment of the hollow viscose aerogel fibers was conducted using a microcalorimeter. The test temperature ranged from 100℃ to 800℃, and the sample mass ranged from 5 mg to 10 mg. The results are shown below. Figure 5 , Figure 5 The heat release curve (HRR) of the hollow viscose aerogel fiber prepared in Example 1 of this application is shown below. Figure 5 It can be seen that, compared with the hollow viscose aerogel fiber prepared in Comparative Example 6, the peak heat release rate (pHRR) of the hollow viscose aerogel fiber prepared in Example 1 is reduced by 60%, exhibiting excellent flame retardant properties.
[0072] The hollow viscose aerogel fibers were subjected to thermal infrared imaging at a high temperature of 90°C using a thermal infrared imager. The aerogel fibers were woven into a 2cm×3cm fabric with a thickness of 0.3mm and placed on a 90°C hot stage. The results are shown in [reference needed]. Figure 6 , Figure 6 This is a high-temperature thermal infrared image of the hollow viscose aerogel fiber prepared in Example 1 of this application, by... Figure 6 It can be seen that the hollow viscose aerogel fiber samples exhibit excellent thermal insulation performance at high temperatures.
[0073] The hollow viscose aerogel fibers were subjected to thermal infrared imaging at a low temperature of -50℃ using a thermal infrared imager. The aerogel fibers were woven into a 2cm×3cm fabric with a thickness of 0.3mm and placed on a copper platform frozen at -50℃ liquid nitrogen. The results are shown in [reference needed]. Figure 7 , Figure 7 This is a low-temperature thermal infrared image of the hollow viscose aerogel fiber prepared in Example 1 of this application, by... Figure 7 It can be seen that the hollow viscose aerogel fiber samples exhibit excellent thermal insulation performance at low temperatures.
[0074] Example 2
[0075] The difference from Example 1 is that nano-calcium carbonate is used instead of nano-montmorillonite, while the rest is the same as in Example 1, resulting in hollow viscose aerogel fibers.
[0076] Example 3
[0077] The difference from Example 1 is that nano-kaolin is used instead of nano-montmorillonite, while the rest is the same as in Example 1, resulting in hollow viscose aerogel fibers.
[0078] Example 4
[0079] The difference from Example 1 is that γ-methacryloxypropyltrimethoxysilane is used instead of bis(triethoxysilyl)ethane, while the rest is the same as in Example 1, to obtain hollow viscose aerogel fibers.
[0080] Example 5
[0081] The difference from Example 1 is that vinyltrimethoxysilane is used instead of bis(triethoxysilyl)ethane, otherwise it is the same as Example 1, and hollow viscose aerogel fibers are obtained.
[0082] Comparative Example 1
[0083] The difference from Example 1 is that after obtaining the wet fibers, supercritical CO2 drying was used directly. Otherwise, it is the same as Example 1 to obtain hollow viscose aerogel fibers.
[0084] Electron microscopy was performed on the hollow viscose aerogel fibers prepared in Comparative Example 1. The results are shown in [reference needed]. Figure 8 , Figure 8 This is a scanning electron microscope (SEM) image of the surface of the hollow viscose aerogel fiber prepared in Comparative Example 1 of this application. Figure 8 It can be seen that the pore size of the aerogel fiber without solvent replacement is significantly larger than that of the aerogel fiber after solvent replacement.
[0085] Comparative Example 2
[0086] The difference from Example 1 is that after obtaining the wet fibers, the wet fibers were replaced in 100% tert-butanol, while the rest was the same as in Example 1, to obtain hollow viscose aerogel fibers.
[0087] Comparative Example 3
[0088] The difference from Example 1 is that after obtaining the wet fibers, the wet fibers were replaced in a 25% tert-butanol aqueous solution. Otherwise, the same as in Example 1 was used to obtain hollow viscose aerogel fibers.
[0089] Comparative Example 4
[0090] The difference from Example 1 is that no nano-montmorillonite is added, but everything else is the same as in Example 1, resulting in hollow viscose aerogel fibers.
[0091] Comparative Example 5
[0092] The difference from Example 1 is that bis(triethoxysilyl)ethane is not added, but otherwise it is the same as Example 1, resulting in hollow viscose aerogel fibers.
[0093] Comparative Example 6
[0094] The difference from Example 1 is that nano-montmorillonite and bis(triethoxysilyl)ethane are not added, but otherwise the same as in Example 1, resulting in ordinary hollow viscose aerogel fibers.
[0095] The hollow viscose aerogel fibers prepared in Examples 1-5 and Comparative Examples 1-6 were subjected to performance tests according to the method described above. The results are shown in Table 1, which contains the performance parameters of the hollow viscose aerogel fibers prepared in the examples and comparative examples of this application.
[0096] Table 1 Performance parameters of hollow viscose aerogel fibers prepared in the embodiments and comparative examples of this application.
[0097]
[0098] As shown in Table 1, the air gel fiber obtained by adding inorganic nanofillers and silane coupling agents and using stepwise solvent replacement exhibits a lower peak heat release rate, higher tensile strength and lower thermal conductivity, thus demonstrating better mechanical and thermal insulation properties.
[0099] The above description is merely a preferred embodiment of this application, but the scope of protection of this application is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in this application, based on the technical solution and inventive concept of this application, should be included within the scope of protection of this application.
Claims
1. A method for preparing a polar bear fur-like air-gel fiber, comprising the following steps: Using water as the inner axis solution and viscose spinning solution as the outer axis solution, spinning is carried out using a coaxial wet spinning device, and wet fibers are obtained after being drawn in a coagulation bath. The wet fibers are sequentially subjected to a first displacement in a first solvent and a second displacement in a second solvent, and then dried to obtain air gel fibers. The first solvent and the second solvent are independently mixtures of water and organic solvents, wherein the concentration of the organic solvent in the second solvent is greater than the concentration of the organic solvent in the first solvent.
2. The preparation method according to claim 1, characterized in that, Also includes: The wet fibers obtained by the second displacement in the second solvent are then subjected to the third displacement in the third solvent and the fourth displacement in the fourth solvent. The third and fourth solvents are independently mixtures of water and organic solvents, wherein the concentration of the organic solvent in the fourth solvent is greater than the concentration of the organic solvent in the third solvent, and the concentration of the organic solvent in the third solvent is greater than the concentration of the organic solvent in the second solvent.
3. The preparation method according to claim 2, characterized in that, The concentration of the organic solvent in the first solvent is 20 vol% to 30 vol%. The concentration of the organic solvent in the second solvent is 45 vol% to 55 vol%. The concentration of the organic solvent in the third solvent is 70 vol% to 80 vol%. The concentration of the organic solvent in the fourth solvent is 90 vol% to 100 vol%.
4. The preparation method according to any one of claims 1 to 3, characterized in that, The organic solvent is selected from one or more of tert-butanol, ethanol, and acetone.
5. The preparation method according to any one of claims 1 to 3, characterized in that, The viscose spinning solution comprises cellulose xanthate, inorganic nano-additives, silane coupling agent, sodium hydroxide, and water; The concentration of cellulose xanthate in the viscose spinning solution is 5wt%~10wt%; The concentration of inorganic nano-additives in the viscose spinning solution is 0.1wt%~1wt%; The concentration of silane coupling agent in the viscose spinning solution is 0.2wt%~0.8wt%.
6. The preparation method according to claim 5, characterized in that, The inorganic nano-additives include one or more of nano-montmorillonite, nano-calcium carbonate, and nano-kaolinite. The silane coupling agent includes one or more of bis(triethoxysilyl)ethane, γ-methacryloxypropyltrimethoxysilane, and vinyltrimethoxysilane.
7. The preparation method according to any one of claims 1 to 3, characterized in that, The inner needle diameter of the coaxial wet spinning device is 0.3mm~0.5mm, the outer needle diameter is 0.5mm~1mm, and the extrusion rate is 100μL / min~500μL / min.
8. The preparation method according to any one of claims 1 to 3, characterized in that, The coagulation bath comprises sulfuric acid, sodium sulfate, and water; The mass ratio of sulfuric acid, sodium sulfate and water is 5~10:5~10:80~90.
9. The air-gel fiber mimicking polar bear fur prepared by the preparation method according to any one of claims 1 to 8.
10. The application of the polar bear fur-like air-gel fiber prepared by the preparation method according to any one of claims 1 to 8, or the polar bear fur-like air-gel fiber according to claim 9, in the preparation of vehicle interior, clothing, or furniture fabrics.