Poly(ethylene‐co‐vinyl alcohol) and Nylon 6/12 nanofibers produced by melt electrospinning system equipped with a line‐like laser beam melting device

Abstract

A new melt electrospinning system equipped with a line-like laser beam melting device developed for the mass production of nanofibers is introduced; this system enables fibers to be produced from locally melted polymer sheets in the presence of an electric field. Using this system, fibers were produced from poly(ethylene-co-vinyl alcohol)(EVOH) and Nylon 6/12 sheets. The fiber formation mechanism was investigated with a video camera and a thermographic camera. It was found that (1) many Taylor cones are formed on the molten end surface of the sheet at almost regular intervals; (2) a single fiber is produced from the apex of each Taylor cone; and (3) the temperature in the Taylor cone changes markedly during the fiber production. Furthermore, it is found that fibers with an average diameter smaller than 1 lm can be produced from EVOH and Nylon 6/12 sheets by the optimization of manufacturing parameters such as laser output power, voltage, sheet thickness and the feed rate of the sheet.

Melt-Electrospun Polyethylene Nanofiber Obtained from Polyethylene/Polyvinyl Butyral Blend Film

“…Using a CO 2 laser heating source, we introduce a new electrospinning technique that simplifies the high-temperature setup of M-ESP [10]. Our laser melting system eliminates the need for a conventional reservoir for molten polymer, resulting in nozzle-free efficient electrospinning with lower energy consumption [11][12][13][14]. The thermal degradation of the polymer melt caused by long-term heating is also avoided by highly controlled and localized laser heating [15].…”

“…No PE fiber less than 1 µm in average diameter has yet been reported, using M-ESP. In our laboratory, nanofibers were successfully obtained using the laser M-ESP system from various polymers with polar groups, namely ethylene-vinyl alcohol copolymer (EVOH) [11,13,14], polylactic acid (PLA) [10], and nylon 6/12 [14]. However, nanofiber could not be obtained from a single polymer substance without a polar group, such as PP, PE, etc.…”

Melt Electrospinning Designs for Nanofiber Fabrication for Different Applications

“…A new laser melt electrospinning process was introduced in 2010 by Shimada et al [67]. It was equipped by a line laser beam to increase the fiber production.…”

“…In addition, unstable surface tension and spin line cohesive fractures have been reported as challenges in obtaining electrospun fibers of consistent diameter under the submicrometer scale [28,34,107]. Although several attempts have been implemented to improve the productivity of melt electrospun fibers, few commercialized large-scale industrialized apparatus are available for melt electrospinning production nowadays [67,77,108,109]. In spite of the fact, that the small hand-operated Wimshurst generator melt electrospinning setup was designed for in-situ wound dressing, researchers are still struggling to develop a portable melt electrospinning apparatus [110].…”

Uniform Distribution and Densification of Jets in Needleless Electrospinning Using Annular Tip Nozzle

“…The distance between the jets was large, about 5.2 mm, and uneven. A linear laser was used to heat the polymer sheet into melt, making the jets distribute in a linear array under the action of the electrostatic field [16]. The minimum jet spacing was 4.5 mm and there was still unevenness.…”