Two core–shell-structured polystyrene/poly­(vinyl pyrrolidone) (PS/PVP) and PVP/PS composite fibers were prepared via coaxial electrospinning in this study. Different concentrations of PVP solutions with a variety of viscosities and conductivities were adopted in the experiment. The influences of both viscosity and conductivity on the Taylor cone, jet motion, morphology, and internal structure of the resultant core–shell fiber were investigated in a comprehensive and systematic manner. As shown in the images of Taylor cone and jet motion, which were captured by a high-speed camera, different PVP concentrations in the core and shell would result in different core and shell thicknesses as well as distinct jet motion patterns including straight jet length, envelop angle, and frequency of whipping process, thus obtaining the core–shell fibers with different diameters. Not only jet motion and Taylor cone but also the polymer solution concentration and the role of PVP in core and shell have a tremendous influence on the morphology and the internal structure of the resultant core–shell fiber. Additionally, the formation mechanisms of PS/PVP and PVP/PS fibers were studied by means of Fourier transform infrared (FTIR). The experimental results provide a basis for further design and optimization of processing conditions, so as to control the nanostructure of core–shell composite fibers.

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The demands for novel approaches that ensure stability in lithium-ion batteries are increasing and have led to the development of new materials and fabrication strategies.

Filtering of industrial PM 2.5 is a major challenge for global environmental and animal protection. Filtering of materials with excellent thermal stability and other comprehensive performances is required for the removal of fine particles in high-temperature operating industries such as steel, cement, metallurgy, incineration, etc. In this study, a meta-aramid/polysulfone-amide (PMIA/ PSA) composite nanofibrous filtration membrane is prepared via solution electrospinning for the development of high-temperature-resistant filtering products. To maximize the merits of each component, PMIA/PSA composite nanofibrous membranes with different mass blending ratios are prepared to determine the optimal balance. It is found that the PMIA/PSA composite nanofibrous membranes show excellent thermal stability and thermal shrinkage performance. They also maintain superb mechanical retention ratios after 200 h treatment at 200 °C. In addition, they exhibit excellent removal efficiency of polystyrene aerosol (PSL) particles of various sizes. It is found that the removal efficiency of PMIA/PSA (3/7) is 96.7% for 0.1 μm, 98.3% for 0.2 μm and 99.6% for 0.3 μm particles and it possesses optimal filtration resistance (79 Pa), while other composite membranes can reach a removal efficiency of over 99.7%. Our experimental results illustrate that the filtration efficiency for PM 2.5 of PMIA/PSA (7/3), (5/5) composite nanofibrous membranes is still kept as high as 99.9% even after being treated at 200 °C for 120 h. It indicates that the prepared composite nanofibrous membranes have potential for applications where high-efficiency filtration is desired, such as bag dust filters for use under high temperatures.

In this study, a novel approach and the related electrospinning equipment were developed to fabricate a new type of polyester staple yarn wrapped with poly(sulfone amide) (PSA) fibers at the nanoscale. As the number of tubes of spinnerets, electrospinning voltage, and rotation speed of the funnel collector have effects on the structure and properties of the nanowrapped yarns, three series of wrapped yarns were prepared using the self-developed electrospinning and wrapping equipment; these wrapped yarns at the nanoscale were characterized systematically by scanning electron microscopy (SEM), thermogravimetry (TG), and infiltration evaluation. The three-dimensional electric field of the electrospinning system used for the nanowrapped yarn was simulated to model the electric fields of different electrospinning spinnerets. Our experimental results showed that the mechanical, thermal, and hygroscopicity properties of the nanowrapped yarns fabricated in this work were clearly improved obviously in comparison with those of single polyester yarns. The nanowrapped yarn has a core−shell structure composed of both nanoscale PSA fibers and micron-scale poly(ethylene terephthalate) (PET) fibers, so that it can unite and inherit the excellent thermal properties of the PSA and the excellent mechanical properties of polyester yarns. The newly developed nanowrapped yarns have potential applications in the development of high-performance industrial textiles and apparel in the future.

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It has been widely acknowledged that the moisture (sweat) management in the textile is a crucial performance to adjust human comfort. Herein, a double‐layered fibrous mat of modified polypropylene (PP)/cotton fabric for the function of directional moisture transport was reported. The PP fibers were deposited on the surface of cotton fabric via melt‐electrospinning to form as‐prepared fibrous mat, wherein the PP mat was used as the inner layer and the cotton fabric acted as the outer layer. The as‐prepared fibrous mats were modified by means of plasma treatment and grafting hydrophilic groups for the sake of converting natural hydrophobicity of PP fibers into moderate wettability. After these treatments, sweat can be transport from the inner layer to the out layer rather than accumulating on the surface of the PP layer, while the capillary action of the cotton fabric on sweat was further enhanced. The directional moisture transport was systematically characterized by a moisture management tester and the experimental results exhibited remarkable accumulative one‐way transport index (1,103.1%), outstanding overall moisture management capacity (0.91) within 120 s and high water vapor transport rate (11.3 kg d−1 m−2). Besides, the obtained fibrous mat also provided decent wearability, showing the great application prospects in the moisture (sweat) management of textiles.