Electrospinning is a highly versatile method to process solutions or melts, mainly of polymers, into continuous fibers with diameters ranging from a few micrometers to a few nanometers. This technique is applicable to virtually every soluble or fusible polymer. The polymers can be chemically modified and can also be tailored with additives ranging from simple carbon-black particles to complex species such as enzymes, viruses, and bacteria. Electrospinning appears to be straightforward, but is a rather intricate process that depends on a multitude of molecular, process, and technical parameters. The method provides access to entirely new materials, which may have complex chemical structures. Electrospinning is not only a focus of intense academic investigation; the technique is already being applied in many technological areas.

Electrospinning: A Fascinating Method for the Preparation of Ultrathin Fibers

Electrospinning is a versatile and viable technique for generating ultrathin fibers. Remarkable progress has been made with regard to the development of electrospinning methods and engineering of electrospun nanofibers to suit or enable various applications. We aim to provide a comprehensive overview of electrospinning, including the principle, methods, materials, and applications. We begin with a brief introduction to the early history of electrospinning, followed by discussion of its principle and typical apparatus. We then discuss its renaissance over the past two decades as a powerful technology for the production of nanofibers with diversified compositions, structures, and properties. Afterward, we discuss the applications of electrospun nanofibers, including their use as "smart" mats, filtration membranes, catalytic supports, energy harvesting/conversion/storage components, and photonic and electronic devices, as well as biomedical scaffolds. We highlight the most relevant and recent advances related to the applications of electrospun nanofibers by focusing on the most representative examples. We also offer perspectives on the challenges, opportunities, and new directions for future development. At the end, we discuss approaches to the scale-up production of electrospun nanofibers and briefly discuss various types of commercial products based on electrospun nanofibers that have found widespread use in our everyday life.

Electrospinning and Electrospun Nanofibers: Methods, Materials, and Applications

Electrospinning of polymeric nanofibers for drug delivery applications

This paper presents a review of the principal developments in functionally graded materials (FGMs) with an emphasis on the recent work published since 2000. Diverse areas relevant to various aspects of theory and applications of FGM are reflected in this paper. They include homogenization of particulate FGM, heat transfer issues, stress, stability and dynamic analyses, testing, manufacturing and design, applications, and fracture. The critical areas where further research is needed for a successful implementation of FGM in design are outlined in the conclusions. DOI: 10.1115/1.2777164

https://web.mst.edu/~vbirman/papers/Modeling%20and%20Analysis%20of%20FGM_Review_2007.pdf

Modeling and Analysis of Functionally Graded Materials and Structures

A review on electrospinning for membrane fabrication: Challenges and applications

Electrospun nanofibers are extensively studied and their potential applications are largely demonstrated. Today, electrospinning equipment and technological solutions, and electrospun materials are rapidly moving to commercialization. Dedicated companies supply laboratory and industrial-scale components and apparatus for electrospinning, and others commercialize electrospun products. This paper focuses on relevant technological approaches developed by research, which show perspectives for scaling-up and for fulfilling requirements of industrial production in terms of throughput, accuracy, and functionality of the realized nanofibers. A critical analysis is provided about technological weakness and strength points in combination with expected challenges from the market.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/mame.201200290

Industrial Upscaling of Electrospinning and Applications of Polymer Nanofibers: A Review

TiO 2 (anatase) and TiO 2 /PVP nanocomposite nanofibers with average diameters of 53 and 109 nm, respectively, were synthesized via sol–gel chemistry in combination with an electrospinning process. This produced continuous nanofibers that were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and transmission electron microscopy (TEM). TiO 2 nanofibers were obtained through thermal oxidation of TiO 2 /PVP in air and the weight loss was determined by thermal gravimetric analysis (TGA). Mechanical properties were studied with a nanoscale three-point bending test. Elastic properties of single nanofibers are reported as measured by atomic force microscopy (AFM) three-point bending on a mesoporous membrane as support. The mean of elastic moduli for TiO 2 and TiO 2 /PVP nanofibers were found to be 75.6 and 0.9 GPa, respectively.

Three-point bending of electrospun TiO2 nanofibers

The effect of porosity on the mechanical and fracture behaviour in Al–Si matrix alloy and composites reinforced with SiC particles of 10 and 20 vol.% in the as-cast state and after extrusion process has been studied. Matrix alloy and composites were fabricated by compocasting and extrusion. Samples were characterized by optical microscopy, image analyzer, scanning electron microscopy and tensile tests. The results demonstrate that hot extrusion considerably reduces the porosity, while size and distribution of the reinforcement particles are also affected. In the point of fracture behaviour, the existence of large porosity is more effective.

The mechanical response of Al–Si–Mg/SiCp composite: influence of porosity

Titania nanofibers prepared by electrospinning

This paper demonstrates the successful application of NiCr coatings on stainless steel substrates using a high velocity oxy-fuel technique for corrosion applications. We present preliminary results of fabrication and microstructural characterization of NiCr coatings. These coatings were characterized by means of an optical microscope, image analyzer, scanning electron microscope and X-ray diffraction (XRD). A microhardness tester was used in order to determine the mechanical properties of the coating. Microstructural observations pointed out that the NiCr layers possessed porosity, oxidized, unmelted and semimelted particles, and inclusions. XRD results indicated that the outstanding phase of NiCr powder and coating was Ni. It was also found that the microhardness values decreased from the coating to substrate.

C. Tekmen

Papers

Industrial Upscaling of Electrospinning and Applications of Polymer Nanofibers: A Review

Three-point bending of electrospun TiO2 nanofibers

The mechanical response of Al–Si–Mg/SiCp composite: influence of porosity

Titania nanofibers prepared by electrospinning

NiCr coatings on stainless steel by HVOF technique