Melt electrospinning today: An opportune time for an emerging polymer process

Over the last decade, melt electrospinning has emerged as an alternative polymer processing technology to alleviate concerns associated with solvents in traditional electrospinning. This has resulted in the fabrication of ultrafine fibers from an increasing range of synthetic polymers and composite systems, to materials including ceramics, driving new applications in technical areas such as textiles, filtration, environment and energy as well as biomedicine. In this article, we review the significant advancements in theoretical modeling of the underlying physical principles, coupled with experimental validation using a variety of technical devices and designs that allows well-controlled fiber formation using optimized material and operating parameters. Innovative device designs are indicating avenues towards higher throughput of randomly collected melt electrospun fibers for the production of commodity nonwoven substrates, similar to solution electrospinning and many other industrial fiber-forming processes. However, we identify a recent shift in perception towards melt electrospinning in the literature, where the adaptation of additive manufacturing approaches to device designs enables precise fiber placement with filament resolutions not yet demonstrated by more established melt-extrusion based direct writing technologies. New, highly ordered arrangements of ultrafine fibers with distinctive surface topology, encapsulating and sensing properties are opening new fields of application in areas such as drug delivery, biosensors and regenerative medicine as high performance materials. The development of these materials is reviewed with an emphasis on an area of current research, where melt electrospun scaffolds are contributing to promising treatment strategies to regenerate or replace human tissue and for the new field of in vitro disease models as well as humanized mice models. (C) 2016 Elsevier Ltd. All rights reserved.