Nylon-6 (PA6) nanofiber webs incorporated with boehmite nanoparticles as an electrostatic charging agent were electrospun and their fiber morphology was characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). SEM showed that the median fiber diameter of the PA6 nanofibers was 73 nm and boehmite nanoparticles had little effect on the fiber diameter. The filtration performance of the nanofiber web was measured using 0.3 micron DOP aerosols at a 5.3 cm/s face velocity. Processed and corona charged PA6 nanofiber web showed significant improvement in the submicron aerosol capture efficiency without a change in the air flow resistance compared to the discharged nanofiber web. These results suggest that the electrospinning process imparted electrostatic charge efficiently on the PA6 nanofiber web, and the electrostatic surface potential of a nanofiber web is increased with the incorporation of boehmite nanoparticles.

A simple process for batch or continuous formation of polymer nanofibers and other nanomaterials in the bulk of a sheared fluid medium is introduced. The process may be of high value to commercial nanotechnology, as it can be easily scaled up to the fabrication of staple nanofibers at rates that may exceed tens of kilograms per hour.

This study reports on the effects of BaTiO 3 -a high dielectric constant additive-addition on charging and filtration properties of meltblown polypropylene (PP) electret filters. Since electrostatic capture efficiency of electret filters is mainly dependent on electrical forces, surface potential and aerosol filtration properties were analyzed and compared. Due to quasipermanent nature of electret property, stability of charging and filtration performance was also investigated via following an isothermal charge decay procedure. Addition of BaTiO 3 did not alter fiber morphology significantly. Particularly, the stability of electrostatic filtration performance was found to be promising with the addition of BaTiO 3 . Possible microstructural changes after addition of BaTiO 3 were investigated via wide angle X-ray diffraction. Changes in crystal structure of PP upon addition of BaTiO 3 did not deteriorate electrostatic properties.

Here we describe a nylon-graphene nonwoven (NGN) composite, prepared via melt-blowing of nylon-6 into nonwoven fabrics and infiltrate those with graphene oxide (GO) in aqueous dispersions, which were further chemically reduced into graphene to offer electrical conductivity. The correlation between the conductivity and the graphene loading is described by the percolation scaling law σ = (p - p), with an exponent t of 1.2 and a critical concentration p of 0.005 wt %, the lowest among all the nylon composites reported. Monolithic supercapacitors have been further developed on the nylon-GO nonwoven composites (NGO), via a programed CO-laser patterning process. The nylon nonwoven works as an efficient matrix, providing high capacity to GO and ensuring enough electrode materials generated via the subsequent laser patterning processes. Our best monolithic supercapacitors exhibited an areal capacitance of 10.37 mF cm in PVA-HSO electrolyte, much higher than the 1-3 mF cm reported for typical microsupercapacitors. Moreover, our supercapacitors were able to retain a capacitance density of 5.07 mF cm at an ultrahigh scan rate (1 V s), probably due to the facilitated ion migration within the highly porous nonwoven framework. This is the first report of highly functional nylon-6 nonwovens, fabricated via industrially scalable pathways into low-cost conductive polymer matrices and disposable energy storage systems.

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Here, we describe an electrospun mat of poly(vinyl alcohol) (PVA) and graphene oxide (GO) as a novel solid-state electrolyte matrix, which offers better performance retention upon drying after infiltrated with aqueous electrolyte. The PVA-GO mat overcomes the major issue of conventional PVA-based electrolytes, which is the ionic conductivity decay upon drying. After exposure to 45 ± 5% relative humidity at 25 °C for 1 month, its conductivity decay is limited to 38.4%, whereas that of pure PVA mat is as high as 84.0%. This mainly attributes to the hygroscopic nature of GO and the unique nanofiber structure within the mat. Monolithic supercapacitors have been derived directly on the mat via a well-developed laser scribing process. The as-prepared supercapacitor offers an areal capacitance of 9.9 mF cm at 40 mV s even after 1 month of aging under ambient conditions, with a high device-based volumetric energy density of 0.13 mWh cm and a power density of 2.48 W cm, demonstrating great promises as a more stable power supply for wearable electronics.

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