Ultrafine Fibers Research Articles

Spun of improvised cis‐1,3,4,6‐tetranitrooctahydroimidazo‐[4,5‐d]-Imidazole (BCHMX) in polystyrene nanofibrous membrane by electrospinning techniques

Development of ultra-fine fiber technology and nano-sized materials are widely taking place to enhance the characteristic of different materials. In our study, a newly developed technique was used to produce improvised nano energetic fibers with the exploitation of cis‐1,3,4,6‐Tetranitrooctahydroimidazo‐[4,5‐d] imidazole (BCHMX) to spin in a polystyrene nanofiber membrane. Scanning electron microscopy (SEM) showed the synthesized nanofibrous polystyrene (PS)/BCHMX sheets with clear and continual fiber were imaged with scanning electron microscopy (SEM). Characterization of the produced nanofiber was examined by Fourier Transform Infrared (FTIR), and X-ray diffractometer (XRD). Explosive sensitivity was also evaluated by both BAM impact and friction apparatus. Thermal behavior for the synthesized PS/BCHMX fiber and the pure materials were also investigated by thermal gravimetric analysis (TGA). The results show enhancement in the fabrication of nano energetic fibers with a size of 200–460 nm. The TG confirms the high weight percentage of BCHMX which reaches 60% of the total mass. PS/BCHMX fiber was confirmed with the XRD, FTIR spectrum. Interestingly, XRD sharp peaks showed the conversion of amorphous PS via electrospinning into crystalline shape regarding the applied high voltage. The synthesized PS/BCHMX nanofiber was considered insensitive to the mechanical external stimuli; more than 100 J impact energy and > 360 N initiation force as friction stimuli. PS/BCHMX is considering a candidate tool to deal with highly sensitive explosives safely and securely for explosives detection training purposes.

Ultrafine nanofiber-based high efficiency air filter from waste cigarette butts

Air and water pollution caused by particulate natters (PM) and waste cigarette butts (WCBs) have wreaked havoc across the globe in last several years, where the latter is subtle in nature. This work aims to tackle both the concerns by recycling WCB into air filter, a value-added product, to remove PMs from air. The air filters consist of ultrafine nanofibers extruded from WCB solution in acetone using supersonic solution blowing (SSB). The ultrafine nanofiber layer, sandwiched between two spunbond polyester membranes, demonstrated remarkable particle filtration efficiency (PFE) of 99.99% at PM2 and 99.7% at PM0.1 when tested at face velocity of 0.96 m/s (i.e., 90 L per minute). The ultrafine nanofiber membrane demonstrated unique architectural feature with 94% volumetric porosity and mean fiber diameter of 92.4 ± 1.2 nm. The structural characterization confirmed its identity as cellulose acetate (CA), free of nicotine and various heavy metals which WCBs generally have. The ultrafine fiber diameter and highly porous structure allowed the 3-ply arrangement to operate at high efficiency with a pressure drop (ΔP) of 50.4 Pa at 0.96 m/s, compared to 41.8 Pa of 2-ply spunbond layers, and PFE of 69.2% at PM2. A laboratory-scale multi-layer prototype filter was developed to mimic a commercial HEPA filter which demonstrated a PFE >99.99% at face velocity of 2.12 m/s and PM0.1. The membrane containing ultrafine nanofibers demonstrated enhanced hydrophobicity (contact angle- 132.8°), which could repel water drops of mean size 256 ± 92 μm when impacted at a velocity of 10 m/s, mimicking a sneezing pattern.

Incorporation of Ethylcellulose Microparticles Containing a Model Drug with a Bitter Taste into Nanofibrous Mats by the Electrospinning Technique-Preliminary Studies.

Electrospinning is considered a simple and comprehensive technique to formulate ultrafine fibres by using an electric field. Polymeric nanofibers constitute promising materials in biomedical applications as drug delivery systems. For their preparation, both natural and synthetic polymers are utilised. Owing to the potential use of electrospun nanofibers as an orodispersible drug dosage form, ethylcellulose microparticles containing the antihistamine drug rupatadine fumarate, prepared by the spray drying technique to conceal the drug’s bitter taste, were incorporated into nanofibers. The obtained nanofibrous mats were evaluated for morphology, mechanical strength, disintegration time, the drug solid state and acceptability in terms of taste masking efficiency. Preliminary studies showed that hypromellose used as a single polymer was not a suitable substance for the manufacturing of nanofibers. Therefore, in order to facilitate the obtention of homogeneous nonwovens, different grades of polyethylene oxide (2,000,000–2M-Da and 4,000,000–4M-Da) were added, which improved the quality of the prepared mats. Nanofibers of the most satisfactory quality were obtained from hypromellose (6.5% w/v) and PEO (2M, 0.5% w/v). SEM image analysis has shown that the nanofibers were homogeneous and smooth and possessed a fast disintegration time (below 30 s) and an adequate drug content with a simultaneous taste-masking effect (as indicated by the in vivo and in vitro methods). However, further studies are necessary to refine their mechanical characteristics.

Ultrafine Viscose‐Based Active Carbon Fibers for Iodide‐Ion Adsorption and Supercapacitors

Active carbon fibers (ACFs) with a large specific surface area (SSA) have received widespread attention in various fields, such as environmental treatment and energy storage. Herein, ultrafine viscose‐based active carbon fibers (UVACFs) with large SSAs and micropores are successfully prepared via stabilization, carbonization, and CO2 activation using ultrafine viscose fibers (UVFs) as precursors. The microporous structure and SSA of UVACFs are adjusted by the activation temperature and the morphology and structure are characterized by a scanning electron microscope, X‐ray diffraction, Raman spectroscopy, and N2 adsorption/desorption. As a result, the SSA of UVACFs can reach 591.58 m2 g−1 with the main pore size of 0.52 nm under activation temperature of 900 °C. The adsorption capacity of UVACFs‐900 for iodide ions is as high as 830.3 mg g−1, which is the highest one among reported ACFs. It is attributed to the fact that the pore size of as‐prepared UVACFs is close to the hydration radius of iodide ions (0.335 nm). Moreover, NiCo2O4 is grown uniformly on UVACFs by the hydrothermal method, which shows high capacitance of 2693.3 F g−1 at 1 A g−1 and excellent cycling stability with 94.5% capacity retention after 3000 cycles (10 A g−1).

Fabrication of efficient protein imprinted materials based on pearl necklace-like MOFs bacterial cellulose composites

The acquisition of efficient protein isolation substances is vital for proteomic research, whereas it's still challenging nowadays. Herein, an elaborately designed protein imprinted material based on a bacterial cellulose@ZIF-67 composite carrier (BC@ZIF-67) is proposed for the first time. In particular, due to the ultrafine fiber diameter and abundant hydroxyl functional groups of the bacterial cellulose, BC@ZIF-67 presented a compact arrangement structure similar to a pearl necklace, which greatly promoted template immobilization and mass transfer resistance in protein imprinting technology. Therefore, the protein-imprinted material (BC@ZIF-67@MIPs) fabricated by surface imprinting technology and template immobilization strategy could exhibit ultrahigh adsorption capacity (1017.0 mg g−1), excellent recognition (IF = 5.98) and rapid adsorption equilibrium time (50 min). In addition, based on the experiment outcomes, our team employed BC@ZIF-67@MIPs to enrich template protein in blended protein solutions and biosamples, identifying them as underlying candidates for isolating and purifying proteins.

Antimicrobial properties of PLA membranes loaded with pink pepper (Schinus terebinthifolius Raddi) essential oil applied in simulated cream cheese packaging

Ultrafine fiber membranes of polylactic acid (PLA) 8% (w/v) loaded with pink pepper essential oil (PPEO) in 10, 20 and 30% (w/v) were produced and evaluated for antimicrobial potential against the bacteria Escherichia coli, Salmonella enteritidis, Listeria monocytogenes and Staphylococcus aureus. The membranes were applied in simulated cream cheese packaging and characterized by morphological, thermal, structural, antimicrobial and wettability analysis. The addition of PPEO reduced the diameter of fibers and increased the initial degradation temperature in relation to pure PPEO. The PPEO presented myrcene as major component and had antimicrobial action for S. aureus and L. monocytogenes. The membranes applied to the cream cheese packaging showed inhibitory effect on the 21st day of storage, for L. monocytogenes. For S. aureus, the membranes inhibited the growth of the colonies on days 14 and 21, with reductions of 30 and 62%, respectively. Finally, the ultrafine membranes had hydrophobic character.

Review of the Electrospinning Process and the Electro-Conversion of 5-Hydroxymethylfurfural (HMF) into Added-Value Chemicals.

Electrochemical converters (electrolyzers, fuel cells, and batteries) have gained prominence during the last decade for the unavoidable energy transition and the sustainable synthesis of platform chemicals. One of the key elements of these systems is the electrode material on which the electrochemical reactions occur, and therefore its design will impact their performance. This review focuses on the electrospinning method by examining a number of features of experimental conditions. Electrospinning is a fiber-spinning technology used to produce three-dimensional and ultrafine fibers with tunable diameters and lengths. The thermal treatment and the different analyses are discussed to understand the changes in the polymer to create usable electrode materials. Electrospun fibers have unique properties such as high surface area, high porosity, tunable surface properties, and low cost, among others. Furthermore, a little introduction to the 5-hydroxymethylfurfural (HMF) electrooxidation coupled to H2 production was included to show the benefit of upgrading biomass derivates in electrolyzers. Indeed, environmental and geopolitical constraints lead to shifts towards organic/inorganic electrosynthesis, which allows for one to dispense with polluting, toxic and expensive reagents. The electrooxidation of HMF instead of water (OER, oxygen evolution reaction) in an electrolyzer can be elegantly controlled to electro-synthesize added-value organic chemicals while lowering the required energy for CO2-free H2 production.

Facile fabrication of thermoplastic polymer nanoparticles by combining sea‐island spinning and Rayleigh instability

AbstractSea‐island spinning has been widely used to prepare ultrafine fibers with diameters ranging from nanometers to micrometers in textile industry. However, the use of industrialized sea‐island fibers as a precursor to fabricate polymeric nanoparticles has not been reported. Herein, the thermoplastic poly(vinyl alcohol‐co‐ethylene) (PVA‐co‐PE) nanofibers with ~240 nm were mass produced in an industrial production line, and the effect of thermal annealing on the morphological evolution was investigated. Rayleigh instability driven morphological transition from nanofibers to spherical particles in ethylene glycol system, demonstrating that the regular nanospheres could be fabricated by controlling annealing temperature and time. The PVA‐co‐PE nanoparticles with an average diameter of ~680 nm was obtained after annealing at 100°C for 30 min. As a result, the PVA‐co‐PE nanoparticles can be mass‐produced with 25 kg/day yield in our production line. This study opens a new avenue of research toward the large‐scalable manufacture of polymeric micro/nano particles by combing industrialized sea‐island spinning technology and Rayleigh instability‐induced morphology evolution.

Electrospun Membrane with Ultrafine Fibers for Oil/Water Separation Application

Environmental pollution has become an urgent concern for both nature and human beings because of oily wastewater spills from industries and household appliances. Therefore, the filtration of industrial oily wastewater is now a major problem in the present world. Many types of experiments are being conducted to find a solution for this issue, and researchers are still looking for a cheaper and better solution. A promising response to this issue can be membrane-interfaced oil-water filtration. And the application of Electrospun membranes can successfully solve this matter. It is found that Polyvinylidene Fluoride-based membranes are being used for this process because of their resistance to chemicals and good mechanical strength. Also, Titanium Dioxide particles are a suitable choice because of their non-hazardous properties and solubility with polymer solutions. In this study, Titanium Dioxide nanoparticles were first synthesized by modifying their pH, and then Electrospun Nanofibrous membranes were produced by adding those modified particles with Polyvinylidene Fluoride. A unique preparation method was used to decrease the particle diameter with alkaline agents, which also results in decreased fiber diameter of membranes. The produced membranes showed improved oleophilic properties and hydrophobicity. Finally, membranes were applied and can be associated with the progress of Oil/Water separation purposes, which also can sustain the recycling process of hazardous chemicals and ensure the contribution to a safe environment.

Solution blow spinning of highly deacetylated chitosan nanofiber scaffolds for dermal wound healing.

Biocompatible fibrous scaffolds based on highly deacetylated chitosan were fabricated using high-throughput solution blow spinning. Scanning electron microscopy analysis revealed that the chitosan nanofiber scaffolds had ultrafine and continuous fibers (300-1200nm) with highly interconnected porous structures (30-75% porosity), mimicking some aspects of the native extracellular matrix in skin tissue. Post-treatment of as-spun nanofibers with aqueous potassium carbonate solution resulted in a fibrous scaffold with a high chitosan content that retained its fibrous structural integrity for cell culture. Analysis of the mechanical properties of the chitosan nanofiber scaffolds in both dry and wet conditions showed that their strength and durability were sufficient for wound dressing applications. Significantly, the wet scaffold underwent remarkable elastic deformation during stretch such that the elongation at break dramatically increased to up to 44% of its original length, showing wavy fiber morphology near the break site. The culture of normal human dermal fibroblast cells onto scaffolds for 1-14days demonstrated that the scaffolds were highly compatible and a suitable platform for cell adhesion, viability, and proliferation. Secretion profiles of wound healing-related proteins to the cell culture medium demonstrated that chitosan fibers were a promising scaffold for wound healing applications. Overall, the dense fibrous network with high porosity of the chitosan nanofiber scaffold and their mechanical properties indicate that they could be used to design and fabricate new materials that mimic the epidermis layer of natural skin.

Antibacterial Activity and Mechanism of GO/Cu2O/ZnO Coating on Ultrafine Glass Fiber.

A GO (graphene oxide)/ZnO/Cu2O antibacterial coating was successfully sprayed on the ultrafine glass fibers using room temperature hydrothermal synthesis and air spraying techniques. The microstructures of the antibacterial coating were characterized, and the results showed that the Cu2ONPs (nano particles)/ZnONPs were uniformly dispersed on the surface of GO. Then, the antibacterial properties of the GO/ZnO/Cu2O (GZC) antibacterial coating were evaluated using the disc diffusion test. It was found that the coating exhibits excellent antibacterial properties and stability against E. coli and S. aureus, and the antibacterial rate of each group of antibacterial powder against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) was 100%. To explore the antibacterial mechanism of the GZC antibacterial powder on the ultrafine glass fibers based on the photocatalysis/oxidative stress method, the photoelectric coupling synergistic effect between GZC antibacterial coating was analyzed deeply. The results all showed that the photochemical activity of GZC antibacterial powder was significantly improved compared with pure component materials. The enhancement of its photochemical activity is beneficial to the generation of ROS (including hydroxyl radicals, superoxide anion radicals, etc.), which further confirms the speculation of the photocatalytic/oxidative stress mechanism.

Jet diameter of the first coil in the electrospinning whipping region: the role of fluid viscosity

In solution electrospinning, the ultrafine fiber is derived from the dramatic stretching of the whipping fluid jet. The first coil of the whipping fluid jet with the highest stretch rate plays a vital role in determining the microstructure and physical property of electrospun submicron/micron fibers. However, it still remains challenging to control precisely the stretching and jet diameter of the first coil of the whipping fluid jet. Herein, a comprehensive model for the jet diameter of the first coil of the whipping fluid jet is established, indicating that the jet diameter is a consequence of the balance between viscous and electrostatic forces, and is a function of the fluid viscosity, electric current, and flow rate. Furthermore, the stretch rate of the first coil of the whipping fluid jet is predicted, which decays as a scaling law with an exponent −1/2 along the axial direction. The theoretical predictions agree well with the experimental results. This work compensates for the deficiency of previous diameter models and enriches the mechanism of jet stretching, which can provide a valuable theoretical guide for the structural and functional design of submicron/micron fibers.

Evaluation of piezoelectric behavior and biocompatibility of poly(vinylidene fluoride) ultrafine fibers with incorporated talc nanosheets

AbstractHerein, we fabricated biocompatible ultrafine fibers based on talc nanosheets (TNS)/PVDF composites that can exhibit robust electromechanical responses. Piezoresponse force microscopy (PFM) was extensively used to decode various characteristics, including ferroelectric and piezoelectric coefficients. The 0.5 wt% TNS dispersed ultrafine fibers exhibited well‐defined ferroelectric characteristics with an enhanced piezoelectric coefficient (d33) of ≈43.3 pm/V compared to 10 pm/V measured for the pristine PVDF ultrafine fibers. It was observed that the piezoelectric coefficient values strongly depended on the morphology and electroactive phase fraction of the ensuing composite ultrafine fiber. The advantage of a high aspect ratio and surface charges offered by TNS alongside electrospinning augmented the composite ultrafine fiber's piezoelectric response. Further, in‐vitro cytotoxicity of the TNS/PVDF composite ultrafine fibers was examined using BALB/3T3 fibroblasts based on ISO Standard 10993‐5. Importantly, the new composite fibers showed no cytotoxic response and the exposed fibroblasts showed excellent viability. Thus, these fabricated TNS/PVDF piezoelectric ultrafine fibers are well suited for applications in bioelectronics, especially as flexible wearable electronic devices, including sensors.

Self-Assembly of Ultrafine Fibers with Micropores via Cryogenic Electrospinning and Its Potential Application in Esophagus Repair.

Electrospinning (e-spinning) has been widely applied to fabricate flat films accumulated by microfibers for tissue engineering. In order to acquire an uneven surface morphology, two methods have been applied traditionally. The first uses a designed receiving substrate, which is stable, but suppresses the flexibility. The second uses dual solvents to achieve bimodal distribution of the fiber diameter. However, the bimodal fiber diameter causes inhomogeneity. To solve these challenges, cryogenic electrospinning, using a flat substrate and a single solvent, was performed in this study to obtain uneven films. By applying a low temperature to the flat receiving substrate, uneven e-spun films with wall-like structures were achieved through the self-assembly of uniform filaments. In addition, the wall-like structures enhanced the mechanical properties of the e-spun films. Moreover, the cryogenic e-spinning produced micropores on the fiber surface, which have the potential to promote esophageal epithelial cell adhesion, proliferation and differentiation.

Scalable production of ultrafine polyaniline fibres for tactile organic electrochemical transistors

The development of continuous conducting polymer fibres is essential for applications ranging from advanced fibrous devices to frontier fabric electronics. The use of continuous conducting polymer fibres requires a small diameter to maximize their electroactive surface, microstructural orientation, and mechanical strength. However, regularly used wet spinning techniques have rarely achieved this goal due primarily to the insufficient slenderization of rapidly solidified conducting polymer molecules in poor solvents. Here we report a good solvent exchange strategy to wet spin the ultrafine polyaniline fibres. The slow diffusion between good solvents distinctly decreases the viscosity of protofibers, which undergo an impressive drawing ratio. The continuously collected polyaniline fibres have a previously unattained diameter below 5 µm, high energy and charge storage capacities, and favorable mechanical performance. We demonstrated an ultrathin all-solid organic electrochemical transistor based on ultrafine polyaniline fibres, which operated as a tactile sensor detecting pressure and friction forces at different levels.

Bacterial cellulose: recent progress in production and industrial applications.

Bacterial cellulose (BC) is synthesized as a valuable extracellular biopolymer by several bacteria belonging to the genera of Acetobacter, Achromobacter, Komagataeibacter, Agrobacterium, Bacillus, Azotobacter, Sarcinia, Lactobacillus and Gluconacetobacter. Unlike plant cellulose, since BC does not contain lignin, hemicellulose, pectin, arabinose and other plant-derived contaminants, it can be obtained purely from the culture media without any purification processes. BC exhibits excellent physicochemical and mechanical properties such as purity, high crystallinity, transparency, porosity, high water holding capacity, ultrafine nanoscale fiber network, tensile strength, high degree of polymerization, high surface area, chemical stability and proton conductivity. In addition, BC has become an essential nanomaterial in many industrial processes as it is biocompatible, biodegradable and renewable. In this respect, researchers are focused on the production of BC using low-cost substrates, investigation of potential BC producers, optimization of cultivation conditions, and modification of BC pellicles with different procedures. Based on these researches, this review of recent progress in bacterial cellulose production, both in vivo and in vitro modifications of surface properties of BC and its industrial applications in different areas are discussed in this review.

Coordinating chain crystallinity and orientation by tailoring electrical stretching for fabrication of super-tough and strong organic fibers

High-performance fibers generally require both plastic deformation resistance (strength) and high damage tolerance (toughness). Nevertheless, strength and toughness are inherently incompatible because of the unsatisfied supramolecular structure of polymer fibers. Herein, the principle of coordinating chain crystallinity and orientation by electrospinning technique is shown to resolve the conflict between super toughness and high strength. Using polyethylene terephthalate (PET) as the model system, chain crystallinity and alignment can be simultaneously and dynamically manipulated with polymer ultrafine fibers (UFFs) by precisely controlling the electrical stretching of a spinning jet. The obtained PET UFFs, characterized by loosely packed but highly aligned chain stacks, possessed a true strength of 853 MPa (similar to that of spider dragline silk), super toughness of 415 MJ/m3 (2.5 times higher than that of spider dragline silk), and extraordinary true strain of 210% (four times higher than that of spider dragline silk and exceeding that of highly elastic Spandex filaments). This facile strategy may offer a new paradigm for the development of advanced super-tough and robust materials.

Исследование влияния вида связующего на свойства фильтровальных стекловолокнистых бумаг для очистки воздуха

At the moment, there is a wide variety of materials for air filtration, however, it is necessary to develop new, more efficient and cost-effective materials. Numerous studies have shown that in order to obtain a highly effective filter material for fine air purification from particles of 0.1–0.5 μm, ultrafine and microfine glass fibers should be introduced into the composition. Glass fibers have a whole complex of unique properties: thermal, chemical and biological resistance, high specific surface area, filtering ability, strength and resistance to aggressive media. At the same time, glass fibers, unlike fibers of plant origin, do not have the ability to fibrillate, swell and bond formation. Therefore, a strong filter material requires a binder that provides the necessary technological strength while maintaining the specified filtering characteristics. The study of composite material based on mineral fiber was carried out, polyadherical complexes of aluminum, thermomechanical pulp (TMP), polyvinyl acetate (PVA) and polyethylene (PE) were used as binders. The main indicators are the tensile strength, capillary absorption, resistance to air flow and permeability coefficient. The novelty of this work lies in the application of TMP and PE as binders in the composite material based on glass fibers. The addition of a binder based on TMP to the composition is advisable in the range of 5–30 % of the fiber mass, for PE this range is 2–10 %. The studied composite material with the addition of PE as a binder has sufficient technological strength, a low coefficient of permeability and resistance to air flow. PE can be used as a promising binder for composite filter materials based on glass fibers for air purification.

Natural grass to all-biomass biodegradable tape and superior oil-water separation fabric

Valorization of agricultural and forestry wastes is a promising and meaningful strategy to turn wastes into treasure. Here, we developed a simple and easy-to-scale method to fabricate all-biomass biodegradable tape and superior oil-water separation fabric from the natural grass. The natural Hybrid Pennisetum grass was transformed into the biodegradable and low-cost tapes by partially removing hemicellulose to destroy “biomass recalcitrance” and following a direct dissolution/regeneration process in ionic liquids, because the regenerated all-biomass films from grass exhibit high tensile strength of 58.6 ± 2.9 MPa, which achieves the standard of engineering plastics. In addition, the all-biomass ultrafine fibers with micron-scale diameters were prepared by the air-blowing spinning process. Due to the outstanding hydrophilicity and under-water super-hydrophobicity, the non-woven fabric consisting of 8–12 μm fibers had excellent oil-water separation performance with a super-high flux of exceed 25,000 L•m −2•h −1 (only with gravity) and an extremely high separation efficiency of 100%, which are much better than the previous reports. Furthermore, the all-biomass oil-water separation fabric can be easily prepared and is completely feasible in the high salty solution and acid/alkaline solution. Therefore, a simple and practical process is demonstrated to construct high-performance matetials from low-cost biomass wastes, providing a huge potential in circular economy, environmental protection and bioresource utilization.

Preparation of ultrafine flexible alumina fiber for heat insulation by the electrospinning method

In this work, aluminum isopropoxide is used as the aluminum source, and acetylacetone (Hacac) is used as the ligand to synthesize a precursor, which can be used to prepare ultrafine Al2O3 fibers. Fiber with excellent flexibility is obtained by electrospinning and subsequent heat treatment processes. The uniform diameter of the fiber is approximately 300–400 nm, and it has a compact structure and no surface defects, such as cracks and holes, the lack of which can prevent it from being damaged in the process of flexible behavior, such as folding in half. By analyzing the crystallization transformation process of the Al2O3 precursor fibers, it is found that the precursor begins to transform from amorphous to γ-Al2O3 at approximately 700 °C. After heat treatment at 1000 °C, it completely changed to α-Al2O3, which is 100–200 °C lower than the results reported in previous literature. Even after heat treatment at 1200 °C, the fiber still has good flexibility, which ensures its functional performance. In addition, the thermal conductivity of the prepared Al2O3 fibers was only 0.318 W/m·K at 1000 °C, which can be used as a thermal insulation material in aerospace, high-temperature industries and other fields.