Large-diameter Fibers Research Articles

Management of Chronic and Neuropathic Pain with 10 kHz Spinal Cord Stimulation Technology: Summary of Findings from Preclinical and Clinical Studies.

Since the inception of spinal cord stimulation (SCS) in 1967, the technology has evolved dramatically with important advancements in waveforms and frequencies. One such advancement is Nevro’s Senza® SCS System for HF10, which received Food and Drug and Administration (FDA) approval in 2015. Low-frequency SCS works by activating large-diameter Aβ fibers in the lateral discriminatory pathway (pain location, intensity, quality) at the dorsal column (DC), creating paresthesia-based stimulation at lower-frequencies (30–120 Hz), high-amplitude (3.5–8.5 mA), and longer-duration/pulse-width (100–500 μs). In contrast, high-frequency 10 kHz SCS works with a proposed different mechanism of action that is paresthesia-free with programming at a frequency of 10,000 Hz, low amplitude (1–5 mA), and short-duration/pulse-width (30 μS). This stimulation pattern selectively activates inhibitory interneurons in the dorsal horn (DH) at low stimulation intensities, which do not activate the dorsal column fibers. This ostensibly leads to suppression of hyperexcitable wide dynamic range neurons (WDR), which are sensitized and hyperactive in chronic pain states. It has also been reported to act on the medial pathway (drives attention and pain perception), in addition to the lateral pathways. Other theories include a reversible depolarization blockade, desynchronization of neural signals, membrane integration, glial–neuronal interaction, and induced temporal summation. The body of clinical evidence regarding 10 kHz SCS treatment for chronic back pain and neuropathic pain continues to grow. There is high-quality evidence supporting its use in patients with persistent back and radicular pain, particularly after spinal surgery. High-frequency 10 kHz SCS studies have demonstrated robust statistically and clinically significant superiority in pain control, compared to paresthesia-based SCS, supported by level I clinical evidence. Yet, as the field continues to grow with the technological advancements of multiple waveforms and programming stimulation algorithms, we encourage further research to focus on the ability to modulate pain with precision and efficacy, as the field of neuromodulation continues to adapt to the modern healthcare era.

The Cortical "Upper Motoneuron" in Health and Disease.

Upper motoneurons (UMNs) in motor areas of the cerebral cortex influence spinal and cranial motor mechanisms through the corticospinal tract (CST) and through projections to brainstem motor pathways. The primate corticospinal system has a diverse cortical origin and a wide spectrum of fibre diameters, including large diameter fibres which are unique to humans and other large primates. Direct cortico-motoneuronal (CM) projections from the motor cortex to arm and hand motoneurons are a late evolutionary feature only present in dexterous primates and best developed in humans. CM projections are derived from a more restricted cortical territory (‘new’ M1, area 3a) and arise not only from corticospinal neurons with large, fast axons but also from those with relatively slow-conducting axons. During movement, corticospinal neurons are organised and recruited quite differently from ‘lower’ motoneurons. Accumulating evidence strongly implicates the corticospinal system in the early stages of ALS, with particular involvement of CM projections to distal limb muscles, but also to other muscle groups influenced by the CM system. There are important species differences in the organisation and function of the corticospinal system, and appropriate animal models are needed to understand disorders involving the human corticospinal system.

Determination of the Adhesion Between Electrospun Mats through Peel tests

Electrospinning is an interesting technique widely used in industry to produce complex fibrous structures with tunable porosity and morphology. Yet, little is known about possible delamination between electrospun layers. In the present work, we studied the adhesion between PCL electrospun mats of similar porosity and investigated the effect of different morphologies, solvents and post-treatment on adhesive strength using a T-peel test. The objective is to establish guiding rules for improving the adhesive strength when fabricating multilayered electrospun systems. The effect of fiber diameter was found to be clearly dominant, large diameter fibers (3.6 µm) showing almost 7-fold increase (p<0.0001) of the adhesive strength compared to smaller ones (0.5 µm), while the use of different solvents for the two layers didn’t induce any major change. Heat treatment was also found to improve the adhesive strength. Further study is needed to better understand adhesion mechanisms between electrospun materials. Finally, this T-peel test was found to be an adequate simple tool to test electrospun bilayer materials and evaluate their adhesive strength.

Microstructure and physical properties of composite nonwovens produced by incorporating cotton fibers in elastic spunbond and meltblown webs for medical textiles

The objective of this research was to produce elastomeric nonwovens containing cotton by the combination of appropriate process. Such nonwovens are in demand for use in several healthcare, baby care, and adult care products that require stretchability, comfort, and barrier properties. Meltblown fabrics have very high surface area due to microfibers and have good absorbency, permeability, and barrier properties. Spunbonding is the most economical process to produce nonwovens with good strength and physical properties with relatively larger diameter fibers. Incorporating cotton fibers into elastomeric nonwovens can enhance the performance of products, such as absorbency and comfort. There has not been any study yet to use such novel approaches to produce elastomeric cotton fiber nonwovens. A hydroentangling process was used to integrate cotton fibers into produced elastomeric spunbond and meltblown nonwovens. The laminated web structures produced by various combinations were evaluated for their physical properties such as weight, thickness, air permeability, pore size, tensile strength, and especially the stretch recovery. Incorporating cotton into elastic webs resulted in composite structures with improved moisture absorbency (250%-800%) as well as good breathability and elastic properties. The results also show that incorporating cotton can significantly increase tensile strength with improved spontaneous recovery from stretch even after the 5th cycle. Results from the experiments demonstrate that such composite webs with improved performance properties can be produced by commercially used processes.

Small-diameter optical fibre sensor embedment for ambient temperature cure monitoring and residual strain evaluation of CFRP composite laminates produced by vacuum-assisted resin infusion

Out of autoclave (OoA) processing techniques, such as liquid composite moulding techniques (LCM) and, particularly, the vacuum-assisted resin infusion (VARI) technique, are being used, with increasing success, in replacement of prepreg/autoclave technologies to produce structural aircraft/aerospace polymer composite parts, due to its better cost effectiveness and competitiveness. This work aims to embed Fibre Bragg grating (FBG) sensors to monitor the VARI manufacturing of carbon fibre reinforced polymer (CFRP) composites and evaluate the associated phenomena: ambient curing and post curing reactions and resulting residual strains. The curing kinetics of the epoxy resin system alone was initially studied through isothermal differential scanning calorimetry (DSC) tests and applying the isoconversional Friedman method, and further studied by strain monitoring during ambient curing and post curing resorting to FBG sensors. The FBG sensors in the CFRP laminates were able to detect a subtle increase of strain as infusion of the CFRP started and to measure decreasing strain as resin filled in the dry fabric layers. Subtle strain decrease revealed forming crosslink bonds. Compressive strains measured by the FBG sensors during post curing show that further crosslink takes place. A comparison of resultant residual strains was made between specimens with embedded FBG sensors on small-diameter optical fibres (SDOF) and on large-diameter optical fibres (LDOF).

Effects of the micro/nanostructure of electrospun zein fibres on cells in simulated blood flow environment

In order to prevent thrombosis, reduce intima hyperplasia, and to maintain long-term patency after implantation of an artificial blood vessel, the formation of intact endothelial cells layer on an inner surface of graft is desirable. The present study aimed to improve endothelial cell adhesion by regulating the morphology of the inner surface of artificial blood vessels. Zein fibre membranes with three fibre diameters (small, ~100 nm; medium, ~500 nm; and large, ~1000 nm) were constructed by electrospinning. A flow chamber device was designed to simulate the blood flow environment. The morphology and adhesion of human umbilical vein fusion cells (EA.hy926) on the surface of the fibre membranes were studied under a shear stress of approximately 15 dynes/cm2. The results showed that oriented electrospun zein fibre surfaces with both medium- and large-diameter fibres can regulate the morphology of endothelial cells (EA.hy926), which are aligned by the fibre direction. The three fibre membranes improved the adhesion of endothelial cells significantly compared to that on the flat membrane. When the fibre direction was fixed parallel to the fluid direction, the medium-diameter oriented-fibre membrane could significantly improve the ability endothelial cells to resist shear stress, and there was a significant difference at 1, 2 and 4 h time points compared with the shear stress resistance on the small-diameter and large-diameter oriented-fibre membranes. When the fibre direction was perpendicular to the fluid direction, again the medium-diameter oriented-fibre membrane improved the ability of endothelial cells to resist shear stress significantly at 1 and 2 h time points. It was concluded that by changing the diameter and arrangement of electrospun fibres, cell morphology control and shear stress resistance can be achieved.

Comparative effects of electrospinning ways for fabricating green, sustainable, flexible, porous, nanofibrous cellulose/chitosan carbon mats as anode materials for lithium-ion batteries

To develop a clean and sustainable carbon anode material derived from biomass with desirable properties for lithium-ion batteries (LIBs), bio-nitrogen (N)-doped composite carbon nanofibrous mats (CNFMs) were made using natural cellulose (CE) and chitosan (CS) by means of two different electrospinning ways (single-nozzle and coaxial-nozzle) coupled with pyrolysis. The conventional CNFMs that had a CE/CS ratio of 5:5 showed the best electrochemical performance, corresponding to a high specific capacity of 327 mAh g−1 at 100 mA g−1, good rate performance with specific capacity of 399 mAh g−1 at 30 mA g−1 and 210 mA g−1 at 1000 mA g−1, as well as excellent cycling stability after 300 cycles. The core–shell CNFMs with a thick outer layer of CS and large average fiber diameter (316 nm) at the same CE/CS ratio had higher pyridinic-N and pyrrolic-N contents but a lower degree of graphitization and BET surface area compared to the conventional CNFMs. It was concluded that the bio-N in CS was more uniformly doped into the CNFMs by the single-nozzle electrospinning way than by the coaxial one, and thus more effectively promoted a comprehensive electrochemical performance.

A STUDY TO ASSESS THE EFFECTIVENESS OF HELFER SKIN TAP TECHNIQUE ON PAIN ASSOCIATED WITH INTRAMUSCULAR INJECTION AMONG ADULT PATIENTS IN SELECTED HOSPITALS OF NAVI MUMBAI

Background: Pain management is an integral part of nursing and Nurses have a responsibility to effectively manage patient’s pain. Nurses and doctors play a greater role in minimizing the pain and discomfort during any invasive procedure. Helfer skin tap technique offers a painless IM injection experience. In this technique rhythmic tapping before and during injection over the skin at the site of injection keeps the muscle relaxed and stimulates large diameter fibers. Aims and Objective: To assess the effectiveness of Helfer skin tap technique on pain associated with intramuscular injection among adult patients. To identify the association between the demographic variables and post procedure score on pain associated with intramuscular injection among adult patients. Methods: A quantitative research approach and crossover design was adopted; 40 patients were selected using non probability purposive sampling in selected hospitals of Navi Mumbai. Data was collected using a questionnaire and selfreporting numerical pain rating scale. Results: Study results show that Majority of the respondent belonged to the age group 31-45 years with a frequency of 17 (42.5%). Representation of male respondent was 23(57.5%) and rest of the respondent belonged to female gender. They were educated up to primary level with elementary occupation; their monthly income ranged from Rs. 19,516 – 29,199 and belonged to upper lower class. The maximum respondent was found married 37(92.5%) and had a BMI ranging from 18.5- 24.9(Normal weight). All the respondent was exposed to IM injection during their stay in the hospital. At Post-intervention assessment using the routine technique, 3(7.5%) respondent reported mild pain and 37 (92.5%) reported moderate pain. At Post-intervention assessment using Helfer technique 14(35%) respondents reported mild pain and 26(65%) reported moderate pain. A non-parametric McNemar test was conducted to test the post-test pain comparison between routine technique and H

HIV-related Neuropathy: Pathophysiology, Treatment and Challenges.

HIV-sensory neuropathy (HIV-SN) is a debilitating complication in HIV patients with or without anti-retroviral treatment (ART). Common symptoms of HIV-SN include pain, decreased sensation, paresthesias, and dysesthesias in a symmetric stocking-glove distribution. While HIV-1 protein such as gp120 is implicated in HIV-SN (e.g. impaired large-diameter fiber), ART itself was recently shown to contribute to HIV-SN in HIV patients and impair thin fiber. Multiple host mechanisms may play roles during the pathogenesis of HIV-SN, including neuron-glia interactions in the spinal dorsal horn (SDH), inflammation, mitochondrial dysfunction and endoplasmic reticulum stress. Concurrent infections, such as tuberculosis, also carry a higher likelihood of HIV-SN as well as environmental or genetic predisposition. Pro-inflammatory cytokines such as IL-1, IL2 receptor-alpha, and tumor necrosis factor (TNF) along with abnormal lactate levels have been identified as potential players within the complex pathophysiology of this condition. In this paper, we review the pathophysiology of HIV neuropathy, focusing on the various treatment options available or under investigation. Although several treatment options are available e.g., the capsaicin patch and spinal cord stimulation, symptomatic control of HIV-SN are often challenging. Alternative approaches such as self-hypnosis, resistance exercise, cannabinoids, and acupuncture have all shown promising results, but need further investigation.

Fabrication of Poly(lactic acid) filter media via the meltblowing process and their filtration performances: A comparative study with polypropylene meltblown

Poly(Lactic acid) (PLA) is considered as a promising alternative for petroleum-based synthetic plastic under the rising concerns over the environmental sustainability of polypropylene (PP) filter materials. To adapt PLA for the meltblown filter media production, it is necessary to establish how PLA polymer properties affect the meltblown process, media structure and filtration performance. We investigated the processability and effects of processing parameters on PLA meltblown structures and filtration performances in an industrially relevant setting by utilizing a commercially available low molecular weight PLA resin and a Reicofil meltblowing production line. We were able to fabricate PLA meltblown media comparable with PP meltblown media both in structures and filtration performances. Increasing airflow rate and decrease throughput reduced fiber diameter of PLA meltblown, but at the given processing condition, PLA meltblown tends to have larger fiber diameters than PP meltblown. However, larger diameter did not deteriorate the filtration efficiency of PLA meltblown. Interestingly, the filtration efficiency of PLA meltblown is higher than those of PP meltblown with similar fiber diameters. We also found the solidity of PLA meltblown lower than that of PP meltblown. This further improved filtration performance by improving air permeability. The quality factors of PLA meltblowns were more than double of PP meltblowns’ quality factors when fiber sizes are similar. PLA also exhibited comparable chargeability and charge stability with PP when corona charged.

Highly flexible fiber delivery of a high peak power nanosecond Nd:YAG laser beam for flexiscopic applications.

Minimally invasive laser surgeries that require the use of a flexible endoscope (flexiscope) could benefit from high-energy nanosecond laser pulses delivered through fibers for real-time tissue characterization and phenotyping. The damage threshold of the fiber's glass material limits the maximum amount of deliverable peak power. To transmit high-energy pulses without damaging the fiber material, large-diameter fibers are typically used, leading to a limited bending radius. Moreover, in a large-core fiber, self-focusing can damage the fiber even if the tip remains intact. In this work, we tested a fused-end fiber bundle combined with a beam shaper capable of delivering more than 20 MW (>100 mJ/5 ns). The fiber bundle was tested over more than eight hours of operation, with different bending radiuses down to 15 mm. The results demonstrate, to the best of our knowledge, the highest peak power delivered through a flexible fiber, for a frequency-doubled Q-switched Nd:YAG laser.

Micro- and nanoscale characterization of different natural biomaterials for ocular surface regeneration

Objectives: This study aims to characterize the widely used biological derived membranes in clinics in terms of micro-nano scale mechanical and morphological properties. Within this scope, advanced platelet-rich fibrin (A-PRF), leucocyte-and platelet-rich fibrin (L-PRF) and human amniotic membrane were studied in this research study. Methods: Nano-indentation, optical coherence tomography (OCT), scanning electron microscopy (SEM), and in vitro degradation test were performed for material characterization. Results: The nano-indentation test revealed significantly higher modulus of elasticity and hardness values in A-PRF group, while OCT presented significantly higher thickness measurements when compared L-PRF. A loose 3D architecture formation due to the large pores formed by means of large fiber diameter were observed in A-PRF group. Besides, platelets were observed among the large fibers in A-PRF membranes on the contrary of L-PRF membranes. Low fiber diameter and high cellular separation were recorded in L-PRF group due to the high centrifugal force application. Therefore, it was observed that the platelets were located mostly on the surface of the membranes in L-PRF. The loose 3D architecture of A-PRF membranes is thought to release growth factors for a longer period of time, ensuring cellular integrity. On the other hand, degradation test results indicated that amniotic membranes degrade to about 85% in one week, while L-PRF and A-PRF were lost their initial weights approximately 31% and 40%, respectively. Conclusions: This comparative characterization study of three different natural biomaterials used in a wide range of clinical applications, from dentistry to ophthalmology, was thought to guide surgeons on the selection of site-specific material.

High pulse energy fibre laser as an excitation source for photoacoustic tomography.

A custom fibre laser designed as an excitation source for biomedical photoacoustic tomography has been developed. It is based on a custom-drawn large core diameter fibre (200 µm) that enables high pulse energies (∼10 mJ) to be achieved. The system can provide variable pulse durations (10 - 500 ns) and pulse repetition frequencies (100 Hz - 1 kHz), as well as arbitrary pulse bursts according to specific user defined sequences. The system is also compact and does not require external water cooling. This, along with the flexibility in the temporal characteristics of its output that it offers, will aid the translation of photoacoustic imaging to practical application in medicine and biology.

Electrospun scaffold fiber orientation regulates endothelial cell and platelet properties associated with angiogenesis and hemocompatibility

Artificial scaffolds fabricated for tissue engineering and/or regenerative medicine applications typically aim to resemble specific properties of the innate extracellular matrix of a particular tissue. While there have been successes with this approach, it has become apparent that there are certain scaffold properties that are essential for tissue formation. Other, non-essential, properties, however, can aid in tissue formation but are not required for cell growth, maintenance and the formation of viable tissue engineered scaffolds. We aimed to investigate the role of electrospun scaffold topography on endothelial cell and platelet functions related to vascular growth throughout engineered scaffolds. We hypothesized that the growth and compatibility of cells throughout scaffolds would be enhanced as the scaffold topographical organization increased. To test this, we made use of a customized rotational electrospinning apparatus, which can increase the topographical organization of formed scaffolds. Scaffolds fabricated from cellulose acetate, chitosan and/or poly-caprolactone were tested. Our data illustrates that endothelial cells prefer to be cultured on scaffolds with increasing order and larger fiber diameters. In general, platelet activation, adhesion and aggregation responses were not a function of scaffold composition, however, platelets activation and adhesion was generally reduced in the presence of scaffolds, as compared to samples incubated without scaffolds. These results indicate that engineered scaffold properties should be fine-tuned for particular applications and overall, scaffolds may not need to resemble the extracellular matrix in all physical, mechanical and topographical properties to be successful in tissue engineering applications. Statement of SignificanceWhen designing engineered tissues, one must consider the physical properties of formed scaffolds as a means to control cell growth characteristics throughout the engineered scaffold. To date, there has been little agreement about which scaffold physical properties are essential for tissue growth. Further, it is essential for growing tissue to include patent vascular networks and here we optimized a method to control the organization of fibers within electrospun scaffolds and promote vascular network growth throughout those scaffolds. Importantly, with increasing fiber organization, scaffolds performed better for vascular tissue engineering applications, in terms of endothelial cell and platelet performance.

Quantitative characterization of dielectric properties of polymer fibers and polymer composites using electrostatic force microscopy

We use a new method based on electrostatic force microscopy (EFM) to perform quantitative measurements of the dielectric constants of individual electrospun nanofibers of poly(L-lactic acid) (PLLA), as well as composite fibers of PLLA with embedded multiwall carbon nanotubes (MWCNT-PLLA). The EFM data record the oscillation phase of an atomic force microscope (AFM) cantilever as a function of the AFM tip position. In our experiments the relative dielectric constants ϵ of the sample are measured from the EFM phase shifts vs. the tip-surface separation, according to a simple analytical model describing the tip-surface interactions. We perform a comprehensive study of how the dielectric constant depends on the fiber diameter for both electrospun PLLA and MWCNT/PLLA fiber composites. Our measurements show that EFM can distinguish between dielectric properties of PLLA fibers and fiber composites with different diameters. Dielectric constants of both PLLA and MWCNT-PLLA composite fibers decrease with increasing fiber diameter. In the limit of large fiber diameters (D > 100 nm), we measure dielectric constants in the range: ϵ = 3.4–3.8, similar to the values obtained for unoriented PLLA films: ϵfilm = 2.4–3.8. Moreover, the dielectric constants of the small diameter MWCNT-PLLA composites are significantly larger than the corresponding values obtained for PLLA fibers. For MWCNT-PLLA nanofiber composites of small diameters (D < 50 nm), ϵ approaches the values measured for neat MWCNT: ϵCN = 12 ± 2. These results are consistent with a simple fiber structural model that shows higher polarizability of thinner fibers, and composites that contain MWCNTs. The experimental method has a high-resolution for measuring the dielectric constant of soft materials, and is simple to implement on standard atomic force microscopes. This non-invasive technique can be applied to measure the electrical properties of polymers, interphases, and polymer nanocomposites.

Chronic pain: a long-term sequela of epidermal necrolysis (Stevens-Johnson syndrome/toxic epidermal necrolysis) - prevalence, clinical characteristics and risk factors.

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are associated with various sequelae. Chronic pain, one of these sequelae, has never been systematically evaluated. To assess the persistence of pain in a single-centre cohort of 113 consecutive patients with SJS/TEN. From this cohort, 81 patients were interviewed more than 1year after the initial episode and included in the study. Data were collected according to standardized questionnaires. From the 81 interviewed patients, 52 patients (64%) were painless and 29 patients (36%) were painful. Chronic pain syndrome was associated with a more severe initial acute phase of the disease (larger extent of detachment, higher SCORTEN, increased rate of admission in ICU and complications, and longer hospital stay). Pain was mainly located at the level of eyes (55%), mouth and lower limbs (38-41%), with a moderate daily intensity on average (4.7/10). The 'affective' descriptors prevailed over the 'sensory' descriptors, with the exception of burning and itching sensations. Finally, regarding provoked pain, mechanical allodynia (to brushing and pressure) was more marked than thermal allodynia. The persistence of chronic pain after SJS/TEN is a common phenomenon. Sensory descriptors are consistent with sensitization of both small-diameter nerve fibres (burning and itching sensations) and large-diameter nerve fibres (mechanical allodynia), but the affective-emotional components of pain largely predominate. Complex mechanisms lead to persistent pain as long-term sequela of SJS/TEN, among which mechanisms, psychological factors related to post-traumatic stress disorder probably play a key role.

Characterization of sub-nanosecond pulsed laser amplification with Er:Yb co-doped phosphate glass fibers

We present an experimental characterization of the amplification of sub-nanosecond duration laser pulses at a wavelength of 1538 nm in short custom-made Er:Yb phosphate glass fibers with different core diameters. The fibers vary in their diameter from 100 µm (highly multi-mode) down to 12 µm (single-mode). The peak power, energy per pulse, and spectral shape of the amplified signal are presented. With our input pulses, the measurements show that the large core diameter fibers do not increase the amplification of the 1538 nm signal. We believe this is due to the high re-absorption of the Er3+ ions in the phosphate fiber. The optimal fiber geometry was found to have a core diameter of 20 µm with a length of 14 cm. The maximum peak power is 8.25 kW, corresponding to a net gain of 10.9 dB, with a pulse duration of 0.7 ns and a repetition rate of 40 kHz.

Diabetes mellitus is associated with elevated urinary pyrrole markers of γ-diketones known to cause axonal neuropathy

IntroductionProgressive distal symmetrical axonal neuropathy, a complication of diabetes mellitus (DM), has an unknown cause. Normal physiological metabolism and diabetic dysmetabolism are associated with the generation of γ-diketones. γ-Diketones form...

Constructing the Bridge from Isotropic to Anisotropic Pitches for Preparing Pitch-Based Carbon Fibers with Tunable Structures and Properties.

Synthetic naphthalene pitches (SNPs) with isotropy and anisotropy were prepared by a simple thermal polycondensation method to fabricate pitch-based carbon fibers. The structural characteristic, thermal stability, phase-separation behavior, and melt-spinnability of the SNPs and the structural properties of the derived carbon fibers were systematically investigated. The results show that spinnable SNPs with controllable mesophase contents ranging from 0 to 100 vol % and softening points (210–290 °C) could be easily obtained by a nitrogen-bubbling treatment to improve their thermal stability and melt-spinnability by avoiding the phase separation of liquid crystal (LC) in the pitch. An experimental phase diagram of spinnability and mesophase content is newly proposed for predicting the spinnability of a mesophase-containing pitch. The LC has a significant influence not only on the constituents, structure, and physical properties of the SNPs but also on the final structure and properties of the corresponding pitch-based carbon fibers. The low ash content (less than 0.15 wt %) in the pitch precursor is found to have no obvious effect on the pitch spinnability and the mechanical properties of derivative large-diameter carbon fibers.

Interlocked Dual‐Network and Superelastic Electrospun Fibrous Sponges for Efficient Low‐Frequency Noise Absorption

Traffic noise is a major source of urban noise pollution, with severe threats to the physiological and psychological health of humans. Fibrous sound absorption materials are extensively applied in the control of traffic noise pollution; however, the larger fiber diameters and monotonous internal structure of such materials result in poor low‐frequency sound‐absorbing properties or unsatisfied mechanical properties. Herein, a biomimetic and robust strategy to design ultrastrong and superelastic fibrous sound absorption sponges is reported, which is achieved by integrating a one‐step forming technique of interlocked micro/nano dual fiber networks and an in situ crosslinking approach. The obtained vine‐like interlocked structured fibrous sponges can withstand a tensile force 10 000 times their weight without deformation. Furthermore, the materials also show outstanding compression fatigue resistance and a lightweight feature (8.70 mg cm−3). Most importantly, the interlocked dual‐network‐induced stable fluffy‐stacked structure endows the fibrous sponges with an enhanced low‐frequency sound‐absorbing property (absorption coefficient of 0.93 at 1000 Hz), which is superior to those of commercial and reported sound absorption materials. In addition, the materials also possess good hydrophobicity and temperature resistance. This work opens new pathways for the further development of highly efficient sound‐absorbing materials.