Highly efficient air-assisted multi-jet electrospinning with curved arranged spinnerets

Jianyi Zheng,Jiaxin Jiang,Gaofeng Zheng,Yinbo Pan,Zihan Zhang,Guoyi Kang,Chuanyan Zhou,Juan Liu

doi:10.1063/1.5130531

Abstract

The uniform, rapid, and steady multi-jetting of nanofibers is the key to applying electrospinning technology in mass production. This paper aims to study an air-assisted multi-jet electrospinning method with a curvedly arranged multi-spinneret that can steadily and continuously produce nanofibers. An electrospinning device with a multi-spinneret which utilizes air flow to stretch and constrain jets is developed. The spinnerets are curvedly arranged in a 5 × 5 array, which can reduce the electric field interference between them. The air flow is guided through the gas hood and evenly distributed around each spinneret to form sheath layers, which mitigates the electric field interference between the spinnerets by reducing surface charge density of the jets and which stretches and constrains the jet, improving jetting stability and continuity. The influences of the electric field strength and the collection distance on jet ejection and deposition behavior are studied, and the influence of auxiliary air pressure on jet ejection initiation is also analyzed. The results show that the critical voltage of jet ejection of the central spinnerets is reduced from 8.2 kV to 3.4 kV when the auxiliary air pressure is increased from 0 kPa to 50 kPa, that of the inner spinnerets is reduced from 9.1 kV to 4.0 kV, and that of the outer spinnerets is reduced from 13.1 kV to 5.2 kV. The critical voltage of the outer spinnerets is higher than that of the inner spinnerets, and the critical voltage of the spinnerets in the center is the lowest. The design and development of the multi-spinneret curvedly arranged in a 5 × 5 array and the introduction of sheath air flow provide an effective means for uniform, rapid, and steady multi-jetting of nanofibers, which is beneficial in promoting the use of electrospinning technology in mass production applications.

Highlights

Nanofibers, due to their special electrical, chemical, and mechanical properties, as well as small fiber diameters, large specific surface areas, etc., are widely used for filtering protection membrane,1,2 as lithium ion battery separators,3,4 and in many fields such as ceramic materials,5 biomedicine,6,7 tissue engineering,8 micro/nano-high-sensitivity sensor manufacturing,9–11 and so on
The results show that the critical voltage of jet ejection of the central spinnerets is reduced from 8.2 kV to 3.4 kV when the auxiliary air pressure is increased from 0 kPa to 50 kPa, that of the inner spinnerets is reduced from 9.1 kV to 4.0 kV, and that of the outer spinnerets is reduced from 13.1 kV to 5.2 kV
The design and development of the multi-spinneret curvedly arranged in a 5 × 5 array and the introduction of sheath air flow provide an effective means for uniform, rapid, and steady multi-jetting of nanofibers, which is beneficial in promoting the use of electrospinning technology in mass production applications

Summary

Introduction

Nanofibers, due to their special electrical, chemical, and mechanical properties, as well as small fiber diameters, large specific surface areas, etc., are widely used for filtering protection membrane, as lithium ion battery separators, and in many fields such as ceramic materials, biomedicine, tissue engineering, micro/nano-high-sensitivity sensor manufacturing, and so on. Increasing the number of spinnerets can increase the yield of electrospun fibers to a certain extent, the electric field interference between those spinnerets has a significant negative impact on the multi-jet electrospinning process. In order to improve the electric field interference between multi-jet spinnerets during the electrospinning process, the spinneret spacing shall be appropriately increased. Angammana and Jayaram conducted a detailed exploration of the double-spinneret electrospinning process and obtained similar conclusions to Yang et al. but pointed out that the spacing of negligible electric field interference between the two spinnerets was ≥40 mm. The introduction of sheath air flow reduces the jet surface charge density and mitigates the electric field interference between the charged spinnerets, constraining and stretching the jet during the electrospinning process, which provides a new method for the rapid and steady jet production of uniform electrospun nanofibers.

Objectives

Methods

Results

Conclusion