LONG PATH TOWARDS TO SUCCESS IN ELECTROSPUN NANOFIBER YARN PRODUCTION SINCE 1930's: A CRITICAL REVIEW

Abstract

Direct conversion of nanofibers into a yarn formed by electrospinning has begun to draw attention recently while pioneering attempts in fact go back to 1930s. Once nanofiber yarns are spun successfully by electrospinning, obviously, this would open new gates for many different applications. However, this is still a challenging task and there is no system accepted universally yet. There are more than 20 different approaches available so far but with serious limitations. In this review, they were categorized as (i) systems for production of parallel bundle of nanofibers and (ii) systems for production of twisted nanofiber yarns, presenting potential applicability of each with a critical point of view. The results show that some of the attempts mainly present basic conceptual ideas only. There are some works to produce real twisted nanofiber yarns continuously while mainly funnel, disc, or ring collectors have been used as the twisting element. However, there is limited information regarding stability of spinning system or control of yarn properties. This review also analyses the technical properties of electrospun nanofiber yarns summarizing the available data in terms of yarn properties such as fiber fineness, twist, production speed, mechanical properties, polymer types, and other important parameters available.