Electrospinning versus fibre production methods: from specifics to technological convergence

Abstract

Academic and industrial research on nanofibres is an area of increasing global interest, as seen in the continuously multiplying number of research papers and patents and the broadening range of chemical, medical, electrical and environmental applications. This in turn expands the size of the market opportunity and is reflected in the significant rise of entrepreneurial activities and investments in the field. Electrospinning is probably the most researched top-down method to form nanofibres from a remarkable range of organic and inorganic materials. It is well known and discussed in many comprehensive studies, so why this review? As we read about yet another "novel" method producing multifunctional nanomaterials in grams or milligrams in the laboratory, there is hardly any research addressing how these methods can be safely, consistently and cost-effectively up-scaled. Despite two decades of governmental and private investment, the productivity of nanofibre forming methods is still struggling to meet the increasing demand. This hinders the further integration of nanofibres into practical large-scale applications and limits current uses to niche-markets. Looking into history, this large gap between supply and demand of synthetic fibres was seen and addressed in conventional textile production a century ago. The remarkable achievement was accomplished via extensive collaborative research between academia and industry, applying ingenious solutions and technological convergence from polymer chemistry, physical chemistry, materials science and engineering disciplines. Looking into the present, current advances in electrospinning and nanofibre production are showing similar interdisciplinary technological convergence, and knowledge of industrial textile processing is being combined with new developments in nanofibre forming methods. Moreover, many important parameters in electrospinning and nanofibre spinning methods overlap parameters extensively studied in industrial fibre processing. Thus, this review combines interdisciplinary knowledge from the academia and industry to facilitate technological convergence and offers insight for upscaling electrospinning and nanofibre production. It will examine advances in electrospinning within a framework of large-scale fibre production as well as alternative nanofibre forming methods, providing a comprehensive comparison of conventional and contemporary fibre forming technologies. This study intends to stimulate interest in addressing the issue of scale-up alongside novel developments and applications in nanofibre research.

Forming of Polymer Nanofibers by a Pressurised Gyration Process

“…[ 10,11 ] Due to the expanding demand for nanofi bers across a wide range of industries, there needs to be an improvement in the current state-ofart technologies to mass produce them more consistently, reliably, robustly and cost effectively. [ 12 ] Electrospinning is a well-established technique to generate a wide variety of polymeric fi bers across the micro-to nanometer-scale range. [ 13,14 ] However, this method requires high voltage (kV range) and shows poor cost-yield efficiency as a single fi ber emerges from the end of the nozzle carrying a polymeric solution.…”

Theranostic Fibers for Simultaneous Imaging and Drug Delivery

“…However, time-consuming processes comprising multiple steps are typically required for the preparation of such multifunctional carriers, which are also very difficult to produce on a large scale. 3,[7][8][9][10] New methods for creating nanoscale theranostic systems are thus much sought after.…”

“…Electrospinning is simple and cheap to implement, and a wide variety of functional ingredients can be easily incorporated into the polymer matrix. 8,11,12 Electrospun fibers have been found to be good candidates for a wide variety of biomedical applications such as cardiovascular stents, 13 wound healing, 14 and the controlled release of active ingredients. [15][16][17] Electrospun drug-loaded fibers have been broadly explored for targeted release, for improving the dissolution rate of poorly water-soluble drugs, and for encapsulating multiple functional components.…”

A feasibility study on semi industrial nozzleless electrospinning of cellulose nanofiber

“…This brings into play many challenging tasks, generally related to reliability, quality consistency, and machine maintenance (especially cleaning). The nozzleless electrospinning solves most of these problems due to its mechanical simplicity; however, the process, itself is more complex because of its inherent multi-jet nature [31].…”