High-Speed Electrospinning\nof Ethyl Cellulose Nanofibers\nvia Taylor Cone Optimization

Ethyl cellulose (EC) is one of the most widely used cellulose\nderivatives.\nNevertheless, challenges such as the formation of beaded fibers, low\nyield, and nonporous internal structure persist in electrospinning,\nlimiting functional improvements and industrial applications. This\nstudy invented a groundbreaking high-speed electrospinning technique\nthrough sheath liquid assistance to optimize the Taylor cone, dramatically\nenhancing the yield, morphology, and formation of porous structures\nof EC nanofibers beyond what has been seen in the literature to date.\nOur study emphasizes the crucial role of the sheath liquid’s\nphysical and chemical properties in controlling the morphology and\ndiameter of EC nanofibers. It was discovered that highly polar and\nviscous sheath liquids led to the formation of beaded structures.\nMost importantly, the sheath liquid-assisted method substantially\nincreased the ejection rate of the EC solution tens and hundreds of\ntimes compared to the current low-speed electrospinning method (0.1–1\nmL/h) by refining the shape of the Taylor cone and resolving low productivity\nchallenges in conventional nanofiber production. Meanwhile, increasing\nthe flow rate of the EC or the sheath liquid accelerated the phase\nseparation of EC solutions, thereby promoting the formation of porous\nstructures in EC nanofibers. A pronounced porous structure was observed\nwhen the core EC flow rate reached 25 mL/h or the sheath chloroform\nflow rate reached 20 mL/h. Furthermore, our sheath liquid-assisted\nhigh-speed electrospinning technique demonstrated universal applicability\nto ECs with varying molecular weights. This study comprehensively\naddressed challenges in controlling the yield, morphology, and internal\nstructure of EC nanofibers through sheath-solution-assisted high-speed\nelectrospinning technology. These findings provide an innovative approach\nto developing next-generation electrospinning technologies to enhance\nthe yield and properties of natural polymers for sustainability.