Sulfide Fibers Research Articles

UiO‐66‐NH2 anchored sulfonated polyphenylene sulfide proton exchange membrane with high proton conductivity and low methanol permeability

AbstractThis study loaded different amounts of UiO‐66‐NH2 onto sulfonated polyphenylene sulfide fibers (SPPS), successfully loading UiO‐66‐NH2 on SPPS fibers confirmed by energy dispersive x‐ray spectroscopy, x‐ray diffraction, and Fourier transform infrared spectroscopy. The UiO‐66‐NH2‐X@SFM were then impregnated in Nafion solution to obtain UiO‐66‐NH2‐X@SFM/Nafion composite membranes. The thermal stability, dimensional stability, mechanical properties, proton conductivity, methanol resistance, and other properties of the UiO‐66‐NH2‐X@SFM/Nafion composite membranes were subsequently comprehensively characterized. The proton conductivity of the UiO‐66‐NH2‐8@SFM/Nafion composite membrane at 80°C and 100% RH was measured to be 0.286 S cm−1, which exhibited a significant enhancement of 1.75 times compared with the original membrane. Simultaneously, the composite membrane demonstrated a remarkable reduction in methanol permeation rate. At 40°C and 100% RH, the UiO‐66‐NH2‐8@SFM/Nafion composite membrane has a selectivity of up to 20.7 × 104 S s cm−3 and a single cell density of 88.3 m W cm−2 at 60°C and 100% RH.

Low-loss nodeless hollow-core anti-resonant soft glass fiber for the 4 µm mid-infrared spectral range

Infrared soft glass hollow-core anti-resonant fibers (HC-ARF) with low loss, excellent mode purity, and robust high-power transmission capabilities have vast potential in mid-infrared high-power laser transmission and biomedical fields. Despite this, the fabrication of these fibers still faces formidable challenges, coupled with an incomplete understanding of the transmission characteristics, thereby amplifying the value of further exploration. In this paper, we fabricate a six-cell nodeless infrared HC-ARF originating from purified sulfide glass, synthesized using a meticulous “stack-and-draw” method and dual-gas-path pressure control method. Notably, we experimentally validate the theoretical performance expectations of this fiber. The fiber exhibits outstanding transmission capabilities and optical transmission quality, characterized by a recorded loss of 0.56 dB/m at 4.79 µm. This is already comparable to traditional step-index sulfide fibers, fully demonstrating its tremendous research value and application potential. Our work has successfully fabricated the lowest loss anti-resonant fiber on record in the mid-infrared field, propelling the development of sulfide HC-ARFs into a new phase and laying a solid foundation for the realization of fiber applications in laser transmission and the biomedical field.

The performance promotion of polyphenylene sulfide fibers based on the electron beam irradiation

To give full play to the good performance of polyphenylene sulfide (PPS) fiber, electron beam irradiation was used to promote the property of the PPS fiber. The fibers were irradiated at different doses, and changes in structure and property of PPS fibers were analyzed by X-ray diffraction, moisture regain, heat resistance and thermo-gravimetric analysis. The strength of the specimen increased from 3.75 cN dtex−1 to 3.88 cN dtex−1 at 10 kGy and then decreased. And the elongation of the irradiated fibers decreased after irradiation. The crystalline shape of the fibers did not change and the crystallinity increased from 57.3% to 59.4% and then decreased. Irradiation had the good effect on moisture regain and heat resistance. The moisture regain of PPS fibers increased from 0.28% to 0.74% after 60 kGy irradiation which was 2.6 times of the initial fibers. After heating at 150 °C for 2 h in an oven, the mass loss ratio of the fibers decreased from the original 9.96%–4.97% at 10 kGy dose which was helpful to the application of PPS fiber in high-temperature fields. At the same time, it could be seen from TG data that the maximum loss rate temperature of fibers rose from the initial 526.6 °C–532.7 °C.

Thermally stabilized polyacrylonitrile/polyphenylene sulfide composite membranes for efficient emission control in harsh environments

In harsh and complex environments, the emission of polluted air poses significant challenges to traditional filtration systems. In contrast to conventional approaches which primarily involve the incorporation of antioxidants into filter materials, this study introduces a novel methodology. Here, we employed polyacrylonitrile (PAN) as a coating for polyphenylene sulfide (PPS) fibers. Furthermore, we innovatively utilized a needle punching process in conjunction with segmented heat treatment to manufacture PAN-PPS composite filter membranes capable of withstanding extreme environmental conditions. During the segmented heat treatment process, the molecular structure of PAN coating underwent a series of changes, ultimately transforming into a heat-resistant ring trapezoidal structure, providing protection for PPS fibers that are prone to oxidation, and thereby enhancing the structural stability of composite filter membrane. Experimental results demonstrated a significant improvement in the mechanical properties of PAN-PPS composite fabric after segmented heat treatment, with the tensile strength increasing by 71.7 % and the Young’s modulus by 91.6 %. Additionally, the flame retardancy and hydrophobic properties of composite membranes were significantly enhanced, exhibiting the excellent stability and better filtration performance in extreme environments. This approach not only addresses the challenges posed by incorporating nano antioxidants into the spinning process but also significantly enhances the high-temperature resistance of the materials. This enables PAN-PPS composite filter bags to effectively control the emission of polluted gases in extreme environments. Furthermore, the thermal treatment process of the PAN coating is easy to implement and cost-effective, providing a novel strategy for the development of extremely high-temperature resistant filtering materials. This makes it possible to explore the development of flexible, high-performance air filtering materials for extreme environments in the future.

Development of an asymmetric composite PPS-based bag-filter material through membrane laminating and superfine fiber blending: Lab test, field application and development of numerical models

Dedusting is crucial for air pollution control, and nonwoven needle felt (NWNF) bag-filters are widely applied for this purpose. Surface treatment of the filter materials can enhance NWNF’s performance, but the large discrepancy in pore size between the surface and NWNF layers causes interface effects, impairing reverse cleaning and shortening service life. In this study, a novel PTFE membrane-laminated asymmetrical composite bag-filter was developed, by blending superfine polyphenylene sulfide fiber (PPS) in the original NWNF structure. Image analysis shows a gradual increase in pore size from the surface to the downstream layer. In standard lab-scale tests, the novel M-PPSF-S filter showed moderately higher resistance, significantly longer service life, higher dedusting efficiencies and better cleaning performance, compared to filters without surface laminating and/or superfine fiber blending. Numerical modelling was performed, and the flow fields and pressure distribution in these filter materials were visualized, confirming that M-PPSF-S′ unique structure facilitated the alleviation of interface effect and non-steady flow. M-PPSF-S was further scaled up to treat real flue gas from a coal-fired power plant, where constant good performance was observed over 5 months. This study offers a novel and practical way to develop low-cost, high-performance filter materials for high temperature flue gas treatment.

PPS ultrafine fiber enhanced aramid fiber filter with superior thermal stability and excellent chemical resistance for efficient PM2.5 removal

Polyphenylene sulfide (PPS) fiber is widely used in high-temperature soot filters owing to its high-temperature and chemical stability. However, PPS fiber undergoes a thermal cross-linking reaction in high-temperature environments, leading to a decline in its mechanical properties, and eventually leading to filter material damage and failure. In this work, short para-aramid (PPTA) fiber was introduced into homemade PPS ultrafine fiber by wet dissociation and dry thermal consolidation technologies. The prepared PPS/PPTA ultrafine fiber felt exhibited high filtration accuracy and long-term thermal stability. The filtration efficiency of PPS/PPTA ultrafine fiber felt for PM0.3, PM0.5, PM1.0, PM2.5, PM5.0, and PM10 reached 89.02, 97.34, 99.85, 99.99, 100.00, and 100.00%, respectively, and remained above 98% after 20 cycles. These results were largely consistent with the theoretical values from the filtration model analysis. The PM2.5 filtration efficiency of PPS/PPTA ultrafine fiber felt remained above 99.73% after being placed at 230 °C for 48 h or being soaked in strong acid and alkali solutions for 48 h, indicating its excellent thermal and chemical stability. PPS/PPTA ultrafine fiber felt also possessed structural stability, with a tensile strength and tear index of 32.93 N/cm and 22.77 mN·m2/g, respectively. Due to its excellent comprehensive performance, we believe this PPS/PPTA ultrafine fiber felt provides a new strategy for the refined governance of industrial high-temperature soot.

Preparation of needled nonwoven enhanced silica aerogel for thermal insulation

Benefiting from the advantages of light weight, porosity, high specific surface area and ultra-low thermal conductivity, silica aerogel (SiAG) has been regarded as ideal thermal insulation material. However, the low strength and fragility limited its application. In this paper, the needled nonwoven (NNW) composed of polyphenylene sulfide fibers and pre-oxidized fibers was applied as substrate for incorporating with silica aerogel (SiAG/NNW) to coordinate the heat preservation. Various characterizations were carried out to discuss thermal insulation property. The results showed that SiAG/NNW can last for 4min under butane flame with a certain impact force at about 1300 °C. According to TG analysis, the weight loss of the SiAG/NNW is 5% at 464 °C, which is much higher than individual NNW (327 °C) or SiAG (456 °C). Moreover, the carbon residue rate of the nonwoven was raised from 54.3% to 73.7% at 800 °C after SiAG incorporation. The fiber morphology can still be observed at the flame perforation of SiAG/NNW with low carbonization degree and no obvious decomposition to SiAG. Significantly, thermal protective performance (TPP) values of the SiAG/NNW can reach 1272 kW s/m2 which is twice of the NNW. In conclusion, the prepared SiAG/NNW showed high temperature resistance and excellent thermal insulation, the results also provides a technical scheme for future development of thermal insulation materials at high temperature.

Effect of quercetin on the structure and oxidation resistance of polyphenylene sulfide fiber prepared by melt spinning

Polyphenylene sulfide fiber is easily oxidized at high temperature, thus vastly reducing its application range. In this study, polyphenylene sulfide/quercetin fibers were prepared via melt spinning. The effect of quercetin on the spinnability of the composite fibers was explored, and their cross-sectional morphology, crystalline properties, orientation, tensile properties, thermal stability and oxidation stability were investigated. At the quercetin content of 1.5 wt.%, particle agglomerates and some gasification, causing fluctuations in melt pressure, fiber breakage and poor spinnability, were observed in the polyphenylene sulfide matrix. The addition of quercetin can increase the crystallization temperature of polyphenylene sulfide, shorten its crystallization time, refine the crystalline particles therein, and improve the degree of fiber orientation. At the quercetin content of 1.0 wt.%, the tensile strength and elongation at break of composite fibers increased by 30.8% and 7.6%, respectively, as compared to those of pure polyphenylene sulfide fibers. Moreover, the decomposition temperature and the oxidation induction temperature at a 5% weight loss were 16.3°C and 13.4°C higher than those of the unmodified PPS fibers. The loss of strength of composite fibers subjected to oxidation for 240 h was only 18.4%. The X-ray diffraction results showed that the phenolic hydroxyl groups in the quercetin structure were able to capture free radicals generated during the oxidation of polyphenylene sulfide fibers, as well as inhibit the oxidative degradation reaction and improve the oxidative stability of the fiber. The oxidation resistance mechanism of composite fibers was also proposed.

Facile synthesis strategy for cesium tin halide perovskite crystals toward light emitting devices and anti-counterfeiting flexible fiber.

All-inorganic metal halide perovskites are widely studied because of their excellent photoelectric properties. However, due to the toxicity of CsPbX3 (X = Cl, Br, I) perovskites, it is difficult to apply them on a large scale. The lead-free nature and air stability make Cs2SnX6 (X = Cl, Br, I) perovskites possible candidates to replace CsPbX3 perovskites. Herein, we report the perovskite crystals (PCs) based on Te(IV)-doped Cs2SnCl6: Cs2Sn1-xTexCl6. Cs2Sn1-xTexCl6 PCs showed yellow emission under a 365 nm ultraviolet lamp. The photoluminescence quantum yield (PLQY) of Cs2Sn0.94Te0.06Cl6 PCs was 57.09%, which was proposed to be from the triplet Te(IV) ion 3P1 → 1S0 self-trapping excitons (STE) recombination. The perovskite crystals can be used to fabricate light-emitting diodes (LEDs). The fiber paper prepared from aramid chopped fibers (ACFs) and polyphenylene sulfide (PPS) fibers showed a bright yellow light under 365 nm ultraviolet light after being post-processed with Cs2Sn1-xTexCl6 PCs solution. The ACFs/PPS compound fiber paper modified with Cs2Sn1-xTexCl6 PCs maintained exceptional optical properties and could be stored in air for more than 4500 h. The fluorescence performance of the modified ACFs/PPS compound fiber paper could be applied to fluorescence anti-counterfeiting. The modification strategy and the applications in this work will provide a good choice for studying the optical performance of perovskites and broaden the application of ACFs/PPS compound fiber paper.

Superhydrophobic polyphenylene sulfide fiber paper with nanofiber network-like structure prepared via regulation of TIPS process for oil/water separation

Superhydrophobic polyphenylene sulfide fiber paper with nanofiber network-like structure prepared via regulation of TIPS process for oil/water separation

OPPS Fibers with High Temperature Resistance and Excellent Antioxidant Properties by an Oxidation Method.

Polyphenylene sulfide (PPS) fiber products have been widely used for separation and filtration in harsh environments due to their excellent chemical resistance and relatively economical price. However, the poor temperature and weak oxidation resistance of PPS significantly shorten its service life under high temperature and strong oxidation environments. Herein, we report a type of oxidation-modified PPS (OPPS) fibers with excellent high temperature and oxidation resistance. This is achieved by oxidizing the thioether sulfide groups in PPS molecular chains into sulfoxide and sulfone groups and cross-linking the intermolecular chains. Both experiments and density functional theory (DFT) calculations indicate that hypochlorous acid (HClO) molecules can rapidly oxidize the PPS fiber surface. In addition, molecular dynamics (MD) simulations prove that there are strong hydrogen bonds and van der Waals interactions between HClO molecules and OPPS molecular chains, which promote the penetration of HClO molecules into the interior of the fiber to complete the layer-by-layer oxidation. The prepared OPPS-20 fibers exhibit excellent structural stability under high temperature and strong oxidant environments. Impressively, the OPPS-20 nonwoven filter still exhibits a high dust filtration efficiency of 99.95% after aging at 320 °C for 12 h, and the corresponding pressure drop is 24 Pa. In addition, the OPPS-20 nonwoven filter also maintains excellent filtration performance after aging in 60% HNO3 solution for 12 h, and the filtration efficiency and pressure drop are 99.96% and 29 Pa, respectively. This work demonstrates that the novel OPPS fibers have excellent application prospects in the field of separation and filtration in harsh environments.

Improving the Oxidation Resistance of Polyphenylene Sulfide Fibers by Doping Copper Nanoparticles Loaded Halloysite Nanotubes

Polyphenylene sulfide (PPS) fiber is widely used in the fields of high-temperature filtration, protective clothing, electronics, automobile, and aircrafts sectors relying on its excellent heat and chemical resistance. However, PPS fiber is easily oxidized under high temperature, which vastly restricts its applications. In this study, using the copper nanoparticles loaded halloysite nanotubes (HNTs@Cu) as a nanofiller, we prepared a PPS composite fiber with improved oxidation resistance. The successful loading of copper nanoparticles into HNTs was demonstrated through TEM and elemental analysis. The crystallinity, orientation, thermal and mechanical properties of PPS nanocomposite fibers were investigated via DSC, XRD, WXRD, TGA and mechanical test. While the mechanical performance of the composite fibers was slightly decreased, the thermal stability was improved when comparing to the neat PPS fiber. The composite fiber with 1.0 wt.% loading of HNTs@Cu showed an over 100% retention rate of breaking strength after thermal oxidative aging, suggesting an improvement in oxidation resistance of PPS fiber. This work provides an effective and accessible method for improving the thermal stability and oxidation resistance of PPS fibers, which thereby helps to extend the applications of PPS fibers in high temperature environment.

Photo-Writable Sulfide Glasses Used to Fabricate Core-Clad Fiber Doped with Pr3+ for Mid-IR Luminescence

With the ultimate goal of developing rare-earth doped chalcogenide fiber fabrication for sensing, amplification, and laser applications, a core/clad germanium-gallium sulfide fiber doped with Pr3+ has been fabricated. The compositions of the core and the clad were selected to ensure the positive ∆n by adding CdI2 and CsCl, respectively, in the GeS2-Ga2S3 matrix. The choice of these compositions was also justified from experimental parameters, including characteristic temperatures and viscosity. Moreover, the permanent photo writability of the sulfide glass family by a femtosecond laser is investigated from the perspective of Bragg grating photo-inscription. Structural investigations by Raman spectroscopy are presented and the effect of the Pr3+ rare-earth ion on the structure is underlined. Finally, the emission of the step-index fiber, made by the rod-in-tube technique between 3.1 µm and 5.5 µm (by pumping at 1.55 µm), is demonstrated.

From S-rich polyphenylene sulfide to honeycomb-like porous carbon with ultrahigh specific surface area as bifunctional electrocatalysts for rechargeable Zn-air batteries

Porous carbon materials possessing high specific surface area (SSA) are promising electrocatalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) in rechargeable Zn-air batteries. However, it is difficult to synthesize porous carbon with high SSA and endow them with high catalytic activity. Herein, Fe, N, S co-doped honeycomb-like porous carbon (Fe–N/S-HPC) with ultrahigh SSA (2223.31 m2 g−1) was achieved through a combined process of KOH activation and pyrolysis using S-rich polyphenylene sulfide (PPS) fibers as precursors. The ultrahigh SSA of Fe–N/S-HPC greatly increases the electrode/electrolyte contact area, while the introduction of heteroatoms (Fe, N, and S) as highly efficient active centers enables the efficient catalytic activity of Fe–N/S-HPC. Notably, the introduced metal presents a unique core-shell structure in Fe–N/S-HPC, with FexOySz as the shell and FexNySz as the core, which can great improve the catalytic activity and durability. Under alkaline conditions, the Fe–N/S-HPC catalyst exhibited outstanding bifunctional oxygen catalytic performance and facilitates the practical application of rechargeable Zn-air batteries. This study not only provides a solution for the rational utilization of PPS fiber waste does not decompose in nature, but also provides new insights for the construction of ultrahigh SSA porous carbon that is needed for industrial applications of rechargeable Zn-air batteries.

Combined effect of interfacial modification and α-ZrP reinforcement on the tribological properties of PPS fabric/phenolic composites

The high strength of polyphenylene sulfide (PPS) fiber subserves the potential application of PPS fabric composites in the field of tribology, but its interfacial adhesion restricts tribological properties. In this research, the 3-(2, 3-epoxy propoxy) propyl trimethoxy silane (KH560) was used to construct a micro-interface on the surface of the fabric, which can significantly enhance the surface roughness and functional groups. Furthermore, the incorporation of Alpha-zirconium phosphate (α-ZrP), a two-dimensional material with excellent thermal stability and chemical resistance, contributed to ameliorate thermal properties of the fabric composites. The results show that the bonding and tensile strength of the modified fabric composites are increased by 32.6% and 35.8%, respectively. More importantly, the wear rate of the modified fabric composites is reduced by 58.5% compared with the original fabric composites.

Optimization of electromagnetic shielding of three-dimensional orthogonal woven hybrid fabrics in ku band frequency region by response surface methodology

Electromagnetic shielding (EMS) has become the necessity of the present era due to enormous expansion in electronic devices accountable to emit electromagnetic radiation. The principal target of this paper is to originate three-dimensional (3D) orthogonal fabrics with conductive hybrid weft yarn and to determine their electromagnetic shielding. DREF-III core-spun yarn using copper filament in the core and polyphenylene sulfide (PPS) fiber on the sheath and fabric constructed of such yarn has a promising electromagnetic shielding characteristic. Box–Behnken experimental design has been employed to prepare various samples to investigate the electromagnetic shielding efficiency of 3D orthogonal woven structures. The orthogonal fabric samples were tested in an electromagnetic Ku frequency band using free space measurement system (FSMS) to estimate absorbance, reflectance, transmittance, and electromagnetic shielding. The increase in copper core filament diameter and hybrid yarn linear density enhances the EMS of orthogonal fabric. Statistical analysis has been done to bring out the effect and interaction of various yarn and fabric variables on EMS. Metal filament diameter, orientation, sheath fibers percentage, and fabric constructional parameters significantly affected electromagnetic shielding efficiency. The inferences of this study can be applied in other 3D structures like angle interlock, spacer fabrics for curtains, and coverings for civilians and military applications.

Experimental Study on Structure and Performance of Dedusting Filter Material Modified by Reducing Graphene Oxide Spraying

With the continuous improvement of social requirements for air quality, industrial dedusting standards are becoming more and more stringent. Bag dust collector is one of the most commonly used and fastest technological dedusting equipment in industrial dedusting places.The filter bag is the core part of the bag filter, and the post-treatment of the filter bag is a common method to improve the performance of the bag filter.In this paper, air spraying method was used to post-treat four kinds of commonly used bag filter bags: polyimide fiber, polyphenylene sulfide fiber, glass fiber needle felt and flumex high temperature needle felt. The structural parameters and performance parameters of four new composites after post-treatment were compared and analyzed.The results showed that a layer of reduced graphene oxide coating was formed on the surface of the modified filter bag. After comprehensive comparative analysis, the reduction effect of graphene oxide composite with polyphenylene sulfide fiber (PPS) is the best. Under the filtration velocity of 0.8m/s, the filtration efficiency of PM1.0, PM2.5 and PM10 increased by 7.3%, 7.6% and 8.2%, respectively. The fiber porosity decreased from 98.36% to 98.18%. The resistance is basically unchanged, and the influence of resistance does not need to be considered when it is used. This study provides a reference for the post-treatment method of the filter bag of the dust collector.

Effect of montmorillonite on the oxidative stability of polyphenylene sulfide fibers prepared by melt spinning

Masterbatches of polyphenylene sulfide (PPS)/organic montmorillonite (MMT) composites were produced via melt blending. A self-made spinning equipment was then used to produce the PPS/organic MMT composite fibers by melt spinning directly from the masterbatches. X-ray diffractometer and transmission electron microscope were used to examine the dispersibility of organic MMT. The morphology, tensile property, crystallization behavior, and oxidative stability of PPS fibers were investigated. The results indicated that organic MMT could be uniformly distributed in the PPS matrix to form a mixed dispersion of intercalated and exfoliated structure and influence the longitudinal surface morphology of fibers to become rough. The roughness of composite fibers surface was proportional to the content of organic MMT. The organic MMT nanolayers could act as the heterogeneous nucleating agents to improve the crystallization, and the crystallity of composite fibers increased with the increase of organic MMT content. The breaking strength of composite fibers first increased and then decreased by increasing the amount of organic MMT. After the oxidation treatment, the breaking strength of neat PPS fibers and composite fibers declined, but the degree of breaking strength loss for composite fibers is lower than that of neat PPS fibers. The dynamic oxidation induction temperature of composite fibers also showed a significant increase by adding organic MMT. Moreover, the addition of organic MMT could limit the chemical combination of element sulfur and oxygen, retard the generation of sulfoxide groups, and induce the conversion of sulfur atoms from C-S bond to sulfone for improving oxidative stability.

High-power mid-IR supercontinuum generation in fluoroindate and arsenic sulfide fibers pumped by a broadband 1.9–2.7 μm all-fiber laser source

We report the experimental demonstration of high-power supercontinuum generation in step-index fluoroindate (InF3) and chalcogenide (As2S3) fibers. A home-built fiber-based laser system with a broad spectrum spanning from 1.9 to 2.7 μm and delivering an output average power of 6.15 W was used as the pump source. A time-averaged power of 2.95 W covering the entire 2–5 μm wavelength range is obtained from an InF3 fiber. Cascading the system by adding an As2S3 fiber, the spectrum was extended up to 5.58 μm. Moreover, we present a supercontinuum with an average power of 440 mW and a spectrum extended to 4.17 μm generated by an As2S3 fiber pumped directly by a broadband (2.4–2.7 μm), silica-based laser source centered at 2.55 µm. Combined with a high degree of spectral flatness, the high-output supercontinuum power highlights the potential of the developed sources for use in a wide variety of applications.

The Performance Promotion of Polyphenylene Sulfide Fibers Based on the Hygroscopic and Dyeable Characteristics

The hygroscopic and dyeable polyphenylene sulfide (PPS) composite fiber was prepared using a twin-screw extruder and a melt spinning machine. A new dyeing process was proposed and the moisture absorption and dyeing mechanism of the composite fiber was analyzed. The results show that sodium polyacrylate (PAAS) is uniformly dispersed in the PPS matrix and is compatible with PPS at the macromolecular level. The thermal properties of the composite fibers are basically unchanged, and the crystallinity is slightly reduced. With the increase of PAAS content, the normal moisture regain of the composite fiber reached 2.11 % from 0.21 %, and the contact angle decreased from 73.8 ° to 52.3 °. Under the new dyeing technology, the dyeing rate of the composite fiber reached 93 %, and the washing fastness was grade 5. The mechanism of hygroscopicity and dyeing of macromolecular space networks and polyelectrolyte was proposed.