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The stable and continuous ejection of multiple jets with high densities is the key to the application of electrospinning technology. An arced multi-nozzle spinneret was designed to increase the production efficiency of electrospinning. The distribution of the electrical field was simulated to optimize the nozzles' distribution of the spinneret. When the nozzles were arranged in an arc array, a relatively uniform electrical field could be obtained, which was beneficial for the weakening of electrical interference among the nozzles. Under the optimized electrical field, multiple jets from each nozzle could be ejected in a stable and continuous way. With the increase of the applied voltage, the electrical stretching force became larger, and there were fewer bonding structures. The average diameter of the electrospun nanofibers decreased with the increase of the applied voltage. When the distance between the inner nozzle and the collector increased, the charged jets suffered a larger stretching effect, resulting in the decrease of the average diameter of the electrospun nanofibers. The electrospinning current increased with the applied voltage and decreased with the distance between the inner nozzle and the collector, which is an important aspect for the monitoring of electrospinning jets. This work provides an effective way to promote the production efficiency of electrospun nanofibrous membranes. [ABSTRACT FROM AUTHOR]

High-efficiency production of nanofibers is the key to the application of electrospinning technology. This work focuses on multi-jet electrospinning, in which a threaded rod electrode is utilized as the needless spinneret to achieve high-efficiency production of nanofibers. A slipper block, which fits into and moves through the threaded rod, is designed to transfer polymer solution evenly to the surface of the rod spinneret. The relative motion between the slipper block and the threaded rod electrode promotes the instable fluctuation of the solution surface, thus the rotation of threaded rod electrode decreases the critical voltage for the initial multi-jet ejection and the diameter of nanofibers. The residual solution on the surface of threaded rod is cleaned up by the moving slipper block, showing a great self-cleaning ability, which ensures the stable multi-jet ejection and increases the productivity of nanofibers. Each thread of the threaded rod electrode serves as an independent spinneret, which enhances the electric field strength and constrains the position of the Taylor cone, resulting in high productivity of uniform nanofibers. The diameter of nanofibers decreases with the increase of threaded rod rotation speed, and the productivity increases with the solution flow rate. The rotation of electrode provides an excess force for the ejection of charged jets, which also contributes to the high-efficiency production of nanofibers. The maximum productivity of nanofibers from the threaded rod spinneret is 5-6 g/h, about 250-300 times as high as that from the single-needle spinneret. The self-cleaning threaded rod spinneret is an effective way to realize continuous multi-jet electrospinning, which promotes industrial applications of uniform nanofibrous membrane. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fabrication strategy inspired by nature mutualism was used. • Optimization of essential oil in preparation of high-performance air filter. • CMA and PHMB work together to achieve functionalization and fiber refinement. • Biopolymer–based air filtration membrane was prepared by one-step electrospinning. • High–performance air filter with antibiosis and mosquito repellent was realized. Composite bio–based multifunctional air filtration is a great challenge and development trend for personal protection. This work was inspired by nature mutualism to produce bio–based and essential oil loaded nanofibrous membrane with multiple functions of high–performance, antibacterial, and mosquito–repellent. The cinnamaldehyde (CMA) and poly(hexamethylene biguanide) (PHMB) were introduced into the cellulose acetate (CA) polymer system to achieve functionalization, and then the CA/CMA/PHMB ultrafine bimodal nanofibrous membrane was prepared through one–step electrospinning. Compared to eugenol, the CMA contributed to the refinement of fiber and minimized the reduction of mechanical properties, thermal stability, and hydrophobicity. On the other hand, the PHMB enhanced jet splitting and synergistically improved antibacterial ability with CMA. The filtration efficiency for PM 0.3 , the pressure drop, and the quality factor were 99.78%, 59.5 Pa, and 0.1028 Pa−1, respectively. The bacteriostatic rates against Escherichia coli and Staphylococcus aureus , and the mosquito–repellent rate were 99.65%, 99.99%, and 92.7%, respectively. Lastly, the batch preparation of this solution was explored, which contributed to commercialization. This work provides a novel and simple approach to efficiently fabricate multifunctional high–performance air filter, which will promote the development of bio–based and sustainable air filter. [ABSTRACT FROM AUTHOR]