Electrospinning needleless

More recently, a composite aerosol filter media has been prepared by depositing polyvinyl alcohol (PVA) nanofibres with mean diameters of about lOOnm on nonwoven fabric substrates by using needleless electrospinning technique. The filtration performance of the composite filter was evaluated by measuring the filtration of sodium chloride nanoparticles (75 20nm). The results showed that the filtration efficiency of the composite filter media for nanoparticles was increased with the increase in thickness of the nanofibre mats, which was controlled by the deposition time of the electrospinning process. 

Yaiin, A.L. and Zussman, E. 2004. Upward needleless electrospinning of multiple nanofibers. Polymer 45 2977-2980. 

It is possible to produce composite nanofibers in an industrialized and cost-effective way as Kostakova et al. [121] did via needleless electrospinning from PVA (polyvinyl alcohol) with cross-linking agents where either MWCNTs or SWCNTs were applied as nanoreinforcement of the nanofibers. It is not obvious whether CNTs are embedded in the fibers in the case of needleless electrospinning because there is no continuous flow through a capillary that assures the CNTs flow with the liquid jets of electrospinning. Raman spectroscopy showed that CNTs are located within the fibers spun from the open liquid surface. 

Kostakova E, Meszaros and Gregr J (2009) Composite nanofibers produced by modified needleless electrospinning, Mater Lett 63 2419-2422. 

Electrospinning (solvent) Long, continuous nanofibres Fibre diameters are quite uniform Wide range of fibre diameters possible Needleless systems have high throughput Small pore size Uniform fibres with diameters <50 nm difficult Needle systems, low productivity Jet instability Solvent recovery issues Low mechanical properties... 

Yarin,A. L. andE. Zussman, Upward Needleless Electrospinning of Multiple Nanofibers. Polymer, 2004,45(9), 2977-2980. 

Jirsak O, Petrik S (2010) Needleless electrospinning-history, present and future. In Proceedings of the 7th international conference-TEXSCI 2010, Czech Republic, Liberec, 6-8 September... 

Recently, a new electrospinning technique has been developed with the capability to produce mass production of nanofibres, which is known as needleless... 

Fig. 4.5 Schematic diagram of experimental set-up for needleless electrospinning, a A layer of magnetic liquid, b a layer of polymer solution, c counter electrode loeated at a distance H from the ee surface of pol3nner, d electrode submerged into magnetic fluid, e high-voltage source and / strong permanent magnet or electromagnet Reproduced from Ref. [82]...

Since 2009, various rotating spinnerets for needleless electrospinning have been built in different shapes such as bowel edge [83], conical wire coil [58], metal plate [84], splashing spinneret [85], rotary cone [86] and moving bead chain [88] (Fig. 4.6). 

Today the research work on needleless electrospinning generally focuses on four areas (1) investigation on the physical principle of needleless electrospinning process to understand the mechanism of controlling fibre quality, (2) experimental study on production parameters, (3) development of electrospinning machine at laboratory, pilot and production levels and (4) development of final fibre products for various purposes [87]. 

Fig. 4.8 Schematic diagram of different stationary needleless spinnerets (electrospinning direction along the red arrow). Reproduced from Ref. [87]...

Fang J, Zhang L, Sutton D, Wang X, Lin T (2012) Needleless melt-electrospinning of polypropylene nanofibres. J Nanomater 2012, Article ID 382639... 

Wang X, Niu H, Lin T (2009) Needleless electrospinning of nanofibers with a conical wire coil. Polym Eng Sci 49 1582-1586... 

Tang S, Zeng Y, Wang X (2010) Splashing needleless electrospinning of nanofibers 50 2252-2257... 

Wang X, Lin T, Wang X (2014) 3D electric field analysis of needleless electrospinning from a ring coil. J Ind Text 44 463-476... 

An alternate design that uses a needleless spinneret to overcome the disadvantages of both needle-based and free-surface electrospinning, whilst controlling the Taylor cone formation is credited to Revolution Fibres Ltd [40], who scaled up this process to achieve continuous production of nanofibres from less than 100 nm to sub-micron range with more than 30 varieties of polymers. Elmarco developed similar techniques with coated wires as spinneret and recently Stellenbosch University has developed a regenerating bubble method [41] as an alternative to needle-based electrospinning. 

Fnm Co., (Fanavaran Nano-Meghyas Research Development Co.) Iran http //en.fnm.ir/ MM, CS Electrolis-Dip , lab scale to industrial electrospinning machines Needle, Needleless, Melt Electrospinning Unknown/trade secret Own design... 

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