Large-scale fabrication of nanofibers by tiny-needle-spaced electrostatic-induction-assisted solution blowing spinning

In this paper, a technology and device for large-scale fabrication of nanofibers called tiny-needle-spaced electrostatic-induction-assisted solution blowing spinning (TESBS) was developed. The airflow stretching force is used as the initial driving force for jet formation in TESBS, which avoids the electric field interference existing in the jet formation stage of multi-needle electrospinning(MES). The addition of an induced electric field in TESBS solves the problem of mutual merging of jets in multi-needle solution blowing spinning (MSBS). The needle spacing of TESBS can be as small as 1 mm, which is much smaller than MES (100 mm) and MSBS (3 mm). The substantial reduction in needle spacing can increase the arrangement density of blunt needles, thereby increasing the output of nanofibers. Compared with MSBS, the average diameter and diameter standard deviation of TESBS nanofibers can be reduced by 52.6% and 78.7%, respectively. Compared with MES, the uniformity of the TESBS nanofiber web has been significantly improved. The formula for the critical needle spacing to ensure that the TESBS jets do not merge with each other was derived. The output of 15-needle TESBS can reach as high as 3 ml/min. The average diameter of TESBS nanofibers decreases with the decrease in injection speed or the increase in voltage. The distance between the needle and the receiver has little effect on the average fiber diameter. TESBS nanofibers with good quality and high yield have broad and bright application prospects in many fields.