This study aims to develop a nonwoven material with excellent conductive properties. We first used four nonwoven materials, namely viscose, polypropylene (PP), nylon, and polyester (PET), as substrates to prepare conductive nonwovens by polymerizing pyrrole monomer and ferric chloride as raw materials. After preliminary experiments, we chose the viscose-based material with the best performance for in-depth study. We optimized the conductive properties by controlling the reaction conditions and explored these conditions. Subsequently, the properties of these samples were thoroughly evaluated using infrared spectral analysis, thermogravimetric analysis, scanning electron microscopy observation, and electrical resistance testing. We found that the prepared conductive viscose nonwovens exhibited optimal electrical conductivity when the pyrrole concentration was 0.6 mol/L, the reaction temperature was 10 °C, and the reaction time was 0.5 h. The results showed that the nonwovens exhibited optimal electrical conductivity. This study not only provides a set of feasible technical solutions for the development of high-performance conductive nonwovens but also lays a solid foundation for the application of such materials in the field of smart wearable devices. Through further research and development, these materials are expected to be widely used in health monitoring and human–computer interaction, thus improving people’s quality of life.

In the engine of heavy trucks, the built-in fuel filter assumes the role of “lungs”. The core of the filter, namely the fuel filter paper, acts as a filter for small impurities and separates oil and water. In order to be able to separate minute impurities from the fuel, in this study, we prepared a novel fuel oil filter paper with high efficiency and high dust holding capacity based on wet-laid forming by laminating PBT/PP two-component melt-blown nonwoven material and cellulose nanocrystals (CNC)-doped cellulose wood fiber pulp with the fiber mesh combination forming technology. The effects of the CNC mixing ratio, surface density of melt-blown nonwoven material layer, surface density of cellulose wood pulp paper layer and calendaring pressure on the pore size and filtration performance of the composite samples were investigated, and the filtration efficiency of the composite samples on the tiny impurities in the fuel were also studied. The results showed that the novel composite fuel filter paper material prepared by the combined forming technology of fibrous web had high filtration efficiency and dust holding capacity, and the filtration efficiency of the composite samples could respectively reach 99.90

Textile-based triboelectric nanogenerators (TENGs) represent a groundbreaking advancement in the field of wearable technology for supplying sustainable energy. In this study, a knitted dual-faced textile-based TENGs was proposed to address the existing challenges of low energy output and poor wearability. The fabric, composed of polytetrafluoroethylene (PTFE) yarn and silver-plated yarn, features a unique intermeshed structure that enhances the corresponding TENG's output performance by increasing the contact area between the tribomaterial and electrode. Such textile-based TENG have demonstrated an ability to attain open-circuit voltage, short-circuit current, and power density up to 133.8 V, 21.9 mu A, and 0.53 W/m2, respectively. More importantly, the dual-faced triboelectric fabric exhibited exceptional damage insensitivity and shape tailorability, making it sustainable for long-term use in wearable devices. The textile-based TENG can power various microelectronic devices, including LED arrays and calculators, showcasing their potential as reliable energy sources for wearable electronics. Furthermore, a real-time wireless direction indication system integrated into a smart garment was developed, demonstrating the TENG's versatility in applications beyond energy harvesting, potentially in navigation assistance. The advent of the dual-faced triboelectric fabric signifies an important step forward in wearable technology, promising enhanced performance and expanded applications in both energy collection and sensing technology.

For sustainable wearable applications, triboelectric nanogenerators (TENGs) should have the features of flexibility, robustness, biocompatibility, and integration. For this purpose, flexible TENGs were proposed using thermoplastic polyurethane (TPU) film with a porous structure and multi-walled carbon nanotubes (MWCNT) was incorporated to enhance the output performance by forming microcapatitors. The conductive fabric was embedded in the friction layer as electrodes, convenient for integration and wearing. Benefiting from the porous structure and microcapatitor effect, the results showed that the output voltage and current of TENG based on the MWCNT@TPU porous composite film increased to 41 V, and 12.4 mu A when the concentration of TPU was 18 wt% and the concentration of MWCNT was 0.3 wt%, from the original 9 V and 1.5 mu A for TENG with dense TPU film. The harvested electric energy was enough to light up 148 LEDs or 18 COBs, as well as charging capacitors for powering micro-electronics. In addition, the TENG could be used for sensing emergency situations and identifying objects. Generally, the designed TENG provides new insights into investigating porous materials with flexibility for high performance energy harvesters.Highlights A wearable, integratable and durable triboelectric layer was developed. The triboelectric layer was optimized by incorporating carbon nanotubes. The outputs of TENG were improved by porous structure and microcapatitor effect. The TENG had a great potential in energy harvesting and protective alarm system.

Textiles have broad application prospects in the fields of flexible sensors and intelligent wearable devices due to their excellent breathability, softness, and structural elasticity. Piezoelectric sensors have become a hot topic in the field of wearable applications due to their ability to perform long-term sensing and detection. This article enhances the performance of composite materials by adding polydopamine (PDA) to improve the interaction between polymer matrix and nanofillers, and optimizes the composite nanofiber membrane synthesized by electrospinning polyvinylidene fluoride (PVDF) and barium titanate (BTO) nanoparticles. The content of β-phase in the optimized PVDF–BTO nanofiber membrane reached 81.58

Flexible strain sensors that mimic the properties of human skin have recently attracted tremendous attention. However, integrating multiple functions of skin into one strain sensor, e.g., stretchability, full-range motion response, and self-healing capability, is still an enormous challenge. Herein, a skin-like strain sensor was presented by the construction of hierarchically structured carbon nanofibers (CNFs), followed by encapsulation of elastic self-healing polyurethane (PU). The hierarchical sensing structure was composed of diversified CNFs with orientations from highly aligned to randomly oriented, and their different fracture mechanisms enabled the resultant strain sensor to successfully integrate key sensing properties including high sensitivity (gauge factor of 90), wide sensing range (∼80% strain), and fast response (52 ms). These properties, combined with high stretchability (870%) and excellent stability (>2000 cycles), allowed the sensor to precisely detect full-range human motions from large joint motions to subtle physiological signals. Moreover, the strain sensor had spontaneous self-healing capability at room temperature with high healing efficiencies of 97.7%, while the healing process could substantially be accelerated by the natural sunlight (24 h → 0.5 h). The healed sensor possessed comparable stretchability, sensing performance, and accurate monitoring ability of subtle body signals with the original sensor. The biomimetic self-healing functionality along with skin-like sensing properties makes it attractive for next-generation wearable electronics.

In this study, a method of preparing conductive film by depositing polypyrrole(PPy) on electrospun CA nanofibers is proposed. With D-CA-PPy electric heating film as the core layer, the upper and lower layers are used as its composite PVDF waterproof and breathable layers to prepare PVDF/D-CA-PPy composite electric heating film. The electric heating film is combined with the clothes through the adhesive lining. Then, the relationship between simulated body temperature and input power is tested, and the application field of the heating film is explored. The characterization results of mechanical properties and water washing resistance show that the breaking strength and elongation of PVDF/D-CA-PPy-laminated electric heating film are improved while maintaining the air permeability. PVDF film effectively prevents PPy from falling off due to water washing. After 50 times of washing, the change rate of resistance is 196

High performance is always the research objective in developing triboelectric nanogenerators (TENGs) for future versatile applications. In this study, a flexible ethyl cellulose/ thermoplastic polyurethane (EC/TPU) nanofiber triboelectric layer with barium titanate (BTO) nanoparticles is proposed for high-performance TENGs, in which electrospun EC/TPU nano fiber membranes supply the high-roughness friction surfaces and piezoelectric BTO nanoparticles are further incorporated to boost the electric outputs by the synergistic effect of piezoelectricity and triboelectricity. Consequently, when the content of the BTO nanoparticle is 8 wt % in the EC/TPU (1:4 in weight ratio) nanofibers, the composite membrane displayed a stress of 9.25 MPa and a strain of 275.2%. The corresponding TENG achieves electric outputs of 125.8 V, 34.1 mu A, and 1.68 W/m2, much higher than those of an individual piezoelectric nanogenerator or TENG. The TENGs are potentially used to supply energy for commercial LEDs and microelectronics and as self-powered sensors to monitor human physical training conditions. This research provides a guideline for developing TENGs with high performance, which is crucial for their long-term use.

Wearable strain sensors have made great progress in sensing performance, stretchability and durability. However, practical applications of these sensors are still quite challenging because they are incapable of detecting multi-degree-of-freedom strains due to the interference of multidirectional strains. Herein, a high-sensing performance, direction-aware and transparent strain sensor is reported based on antimony-doped tin oxide oriented nanofiber (ATO-ONF) films prepared by electrospinning. The monolayer ATO-ONF strain sensor shows remarkable anisotropic sensing performance, namely GFs of 250 and 1.2 for the nanofiber orientation and its transverse directions, suggesting the realization of the unidirectional sensing capability of the strain sensor, i.e., only responding to strains along the nanofiber direction. In addition, this strain sensor also exhibits high transparency with a light transmittance of ~ 80%, and excellent sensing performance including high sensitivity, high linearity, low hysteresis, good repeatability and durability (> 2000 cycles). Based on these superior sensing properties, the direction-aware biaxial strain sensor is designed by orthogonally stacking ATO-ONF films, by which the predicted magnitude and direction of the tensile strains agree well with those of the actual strains. Furthermore, the multi-degree-of-freedom applications of direction-aware strain sensors in human motion monitoring and human-machine interaction are demonstrated, showing a great application potential in next generation wearable electronics.

Particulate matter (PM) pollution has become a serious environmental concern. Nanofibrous filters are widely reported to remove PM from polluted air. Herein, efficient and lightweight PM air filters are presented using airflow synergistic needleless electrospinning composed of auxiliary fields such as an airflow field and a secondary inductive electric field. Compared to needleless electrospinning with other spinnerets, it significantly improves productivity, fiber diameter, and porosity of fibrous air filters. The instant noodle-like nanofiber structure can also be controlled by adjusting the airflow velocity. These air filters exhibit high (2.5 μm particulate matter) PM2.5 removal efficiency (99.9%) and high (0.3 μm particulate matter) PM0.3 removal efficiency (99.1%), low pressure drop (56 Pa for PM2.5 and 78 Pa for PM0.3 ), and large dust holding capacitance (the maximum value is 168 g m-2 for PM2.5 , while 102 g m-2 for PM0.3 ). Meanwhile, the proposed PM filters are also tested suitable and stable to other polluted air filtrations such as cigarette smoke and sawdust. The large-scale synthesis of such an attractive nanofiber structure presents the great potential of high-performance filtration/separation materials.

Textile-based electronics characterizing easy integration into textile garments and good wearability have received considerable attentions. However, it is still a huge challenge to integrate multiple functions into single electronic device, especially for those having different even opposite requirements in electrical properties. In this work, an anisotropic electrically conductive composite was prepared by encapsulating conductive knitted fabric (CKF) into polyurethane (PU). Based on anisotropic electrical conductivity, i.e., extremely low and stable resistivity in the coursewise direction and significant variation of resistivity in the walewise direction during tensile strains, the composite could efficiently integrate the electro-heating and strain-sensing functions that required opposite electrical properties. When applied for electro-heating applications in the coursewise direction, the CKF/PU composite exhibited fast thermal response, ultrahigh electric-thermal conversion (140 degrees C at 4 V), and stable electrothermal performance under a large strain (40%) or after long-term use (>1000 stretching cycles). When applied for strain-sensing applications in the walewise direction, the composite showed good sensing performances, including high sensitivity (GF of -8.1 at a 5% strain), low hysteresis, good reproducibility and stability (>1000 cycles), which enabled the device as a wearable sensor to accurately detect human joint movements and subtle motions. Furthermore, the self-healing function was exploited for the CKF/PU electronic device, by which the abnormal sensing property could be fully repaired at human body temperature. This work may shed new light on the future development of high-performance multifunctional wearable electronics with the anisotropic conducting feature.

Flexible electric heating elements can be integrated into cloths to provide warm for people’s working and living in low-temperature environments and can also provide hyperthermia for elderly and patients. Due to its low energy consumption, reusable, environment friendly, and pollution free, electric heating cloths have a broad market prospect. In this research, a facile method, screen printing, is used to prepare the heating element. Silver paste heating fabric with low resistivity could heat rapidly under low loaded voltage. The Ansys finite element software is used to simulate the Joule heating behavior. The results of the experiment and simulation were highly consistent. Through experiments, theoretical derivation, and simulation analysis, we found that the silver paste heating fabric has a good Joule heating behavior, and the simulation can be applied to the circuit design, implying that it will have a broad application prospect in electric heating clothing fields.

柔性电加热织物是智能加热服装、热致变色服装等智能服装服饰的关键部件.本文总结了近年来柔性电加热织物的研究进展,对柔性电加热织物的基底材料和加热用导电材料进行了分类对比分析,概括了柔性电加热织物的制备方法和性能表征方法,并展望了其在智能服装服饰、智能保健医疗器材领域中的广阔应用前景,最后提出了柔性电加热织物目前存在的问题以及未来发展的方向.

ANSYS finite element simulation software was used to simulate the heating process of silver coated yarns in fabric. The thermal filed distribution of heating fabric in different condition was analyzed by adjusting the distance between the silver coated yarns and output voltage. The heating fabric was prepared by the results of finite element simulation. The electrical heating property of heating fabric was researched and contrast with the results of finite element simulation. The result shows that, the equilibrium temperature of silver coated yarns rise with the increase of output voltage. The temperature is 109.7 degrees C by the output voltage is 7V. The distance of silver coated yarn in fabric is 3mm, which makes the surface temperature of heating uniform while the cost of silver coated yarns is lower. The equilibrium temperature and the heating speed rise with the increase of power density. The results of simulation are consistent with the actual results and the deviation is less than 4.5%. The results of finite element simulation can be important reference to guide the fabrication of heating fabric based on silver coated yarns.

ABSTRACT In this article, the silver‐plated polyamide fabrics (SPPAFs) with high electroconductibility and shielding effectiveness were fabricated by using in situ reduction of polydopamine and chemical silvering. The effects of SPPAFs dopamine (C 8 H 11 O 2 N) and silver nitrate (AgNO 3 ) concentration on surface resistivity and electromagnetic interference shielding effectiveness were studied. The results showed that the surface resistivity of SPPAFs can reach a minimum value of 0.06 ± 0.014 Ω cm −1 , when C 8 H 11 O 2 N concentration is 4 g L −1 and the AgNO 3 concentration is 120 g L −1 . The shielding effectiveness of SPPAFs in the wide frequency range of 10–3000 MHz increases with the increase in the concentration of AgNO 3 , and increases first and stabilizes afterward with increasing C 8 H 11 O 2 N concentration. When the concentration of C 8 H 11 O 2 N and AgNO 3 is 3 and 120 g L −1 , respectively, mean shielding effectiveness values in the low‐, medium‐, and high‐frequency bands are 71.3, 73.8, and 76.1 dB, respectively. Moreover, the mean shielding effectiveness values is 83.79 dB in the frequency range of 1.2–2.3 GHz. The dominant shielding mechanism of SPPAFs is the reflected electromagnetic waves and the absorption shielding effectiveness is less than 2 dB. The average electromagnetic shielding values of SPPAFs are above 67 dB after 16 weeks of storage, when C 8 H 11 O 2 N concentration is 4 g L −1 and the AgNO 3 concentration is 80 and 100 g L −1 . The prepared SPPAFs show promising applications in military textiles and smart wearable clothing. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136 , 48227.

A facile method for preparing an easy processing, repeatable and flexible pressure sensor was presented via the synthesis of modified multi-walled carbon nanotubes (m-MWNTs) and polyurethane (PU) films. The surface modification of multi-walled carbon nanotubes (MWNTs) simultaneously used a silane coupling agent (KH550) and sodium dodecyl benzene sulfonate (SDBS) to improve the dispersibility and compatibility of the MWNTs in a polymer matrix. The electrical property and piezoresistive behavior of the m-MWNT/PU composites were compared with raw multi-walled carbon nanotube (raw MWNT)/PU composites. Under linear uniaxial pressure, the m-MWNT/PU composite exhibited 4.282%kPa−1 sensitivity within the pressure of 1 kPa. The nonlinear error, hysteresis error and repeatability error of the piezoresistivity of m-MWNT/PU decreased 9%, 16.72% and 54.95% relative to raw MWNT/PU respectively. Therefore, the piezoresistive response of m-MWNT/PU had better stability than that of raw MWNT/PU composites. The m-MWNT/PU sensors could be utilized in wearable devices for body movement detection, monitoring of respiration and pressure detection in garments.

This paper presented a novel and facile method for fabricating flexible heating fabrics with temperature perception (FHF-TP), a temperature-sensitive fine copper was integrated into two pieces of flexible fusible interlining fabrics (FFIFs) by a simple thermal bonding method. FHF-TPs were characterized by performing a series of experiments, such as the research on the principle of temperature perception, infrared thermal performance testing, power consumption testing and mechanical properties testing and so on. The results showed the temperature of the FHF-TP was linear correlative strongly with resistance, loaded voltage and power consumption of that. By extracting and analyzing the infrared temperature images on the surface of the FHF-TPs, it was found that reducing the spacing of copper wires and the loaded voltage, improving the thermal conductivity of the bonding fabric can not only increase the heating temperature and heating rate, but also diminish the temperature difference so that the FHF-TPs were kept at a fairly even temperature. And the preset equilibrium temperature of the FHF-TPs is a significant linear correlative with the power consumption of those in the cold environment by simulating the heating in the garments. After performing 240 h ageing at 80 and 100 degrees C and washing for 30 times, the mechanical properties of all FHF-TP samples have no obvious change. FHF-TPs with stable electrical properties, thermal performance and mechanical properties will have wide application prospects in active warming garments field.

Eco-friendly tree-like porous carboxyl modified cellulose nanofiber membranes as highly efficient adsorbents for heavy metal ions were fabricated by the electrospinning of cellulose acetate (CA)/tetrabutylammonium chloride (TBAC)/manganese dioxide (MnO2) solution, and subsequent deacetylation treatment to turn CA into cellulose and citric acid modification to graft carboxyl group on the surface of cellulose nanofibers. The addition of TBAC led to the formation of tree-like structure and MnO2 particles were used as pore-forming agents. The effects of pH, initial ion concentrations and contact time on the removal capacity of heavy metal ions were investigated. During the removal process, the abundant carboxyl groups (–COOH) transferred to carboxylate ions (–COO−) which had stronger ion exchange ability to the metal ion adsorption. In addition, the tree-like porous structure supplied large specific surface area and effectively increased the removal capacity. The removal process could reach a plateau in 90 min with the maximum removal amount of 399.14 mg/g. The removal process was also depicted by Langmuir and Freundlich isotherm model. Generally, the tree-like porous structure will have extensive prospects in the fields of filtration, electrochemistry, tissue engineering and so on.

The polypyrrole knitting fabrics were obtained by in-situ polymerization.The surface temperature of fabrics was measured by infrared camera.The result showed that the fabrics temperature rised with increasing the voltage.The fabrics temperature was proportional to the power density of fabrics.The curve of temperature changing with time was fitted, and the correlation coefficients were larger than 0.9783.The change rate of highest temperature and the stable average temperature was 7.04％ and 3.4％ respectively.Flexible heating knitted fabrics had very broad application prospect in the field of positive warm clothing.

Micro-scale silicon carbide (SiC) fiber mat was produced by blowing of an oil-in-water (O/W) precursor emulsion process combined with a thermal curing treatment and a subsequent calcination at high temperature, which we named emulsion-blow spinning (EBS). An air flow with high velocity was used to attenuate the O/W emulsion jets, and the as-spun fibers can be successfully self-sustained to three-dimensional network structure. Polycarbosilane micelles (precursor) entrapped in an aqueous polyoxyethylene matrix resulted in SiC fibers with crystalline after pyrolysis and ceramic process. The SiC fiber mat was tested with an excellent thermal stability and semi-conductivity, may have potential applications on electronic and energy storage.