Nanofibres production techniques

Electrospinning is a nanofiber production technique from a wide range of polymeric materials. In this section, an introduction to electrospinning process and starting materials, along with the applications of electrochemical sensors based on nanofibrous mats fabricated by the electrospinning process, will be discussed. 

Electrospinning technique has been used not only for the deposition of polymeric nanofibres but also for the production of ceramic nanofibres of PZT. PZT is commonly used in micro- and macro-scale piezoelectric energy harvesting devices due to its high electro-mechanical coupling coefficient of -500-600pC ) as compared... 

In this section, the production of PP nanofibres containing silver nanoparticles using the above technique, together with their characterisations using X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis are presented. Additionally, the antibacterial properties of nanofibres are evaluated using the quantitative American Association of Textile Chemists and Colorists (AATCC) 100 test. The inclusion of nanosilver into polymers to form a nanocomposite has been demonstrated to have a profound effect on the crystallisation of the polymer, which in turn affects the properties of nanofibres, including their antibacterial properties. 

Although the existing fibre-making technique is able to produce a bicomponent fibre of many cross-sectional structures, the production of bicomponent nanofibres has been limited to two basic types of cross-sectional structures, the core-sheath and the side-by-side . These bicomponent nanofibres are eiectrospun via special spinnerets. Two polymer solutions flow within the spinneret as the sheath and core, or side-by-side, to the tip of the nozzle and then are subjected to a co-electrospinning process. The formation of bicomponent nanofibres is determined by the laminar bicomponent jet. 

One of the challenges to the electrospinning technique is for the production of uniform and fine nanofibres (with fibre diameter less than 100 nm) from... 

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

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. 

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