What is electrospinning
Electrospinning is a fibre forming process, which utilizes a high voltage electric field to produce an electrically charged jet of polymer fluid. An electrode charges the polymer fluid droplet; which ejects into a fine fluid jet when the repulsive forces induced by the electrostatic charge overcome the cohesive forces of surface tension and viscoelastisity of the polymer fluid. The jet splits and elongates as it accelerates under the electric field. The solvent from the fine jets evaporate rapidly due to its large surface area and it solidifies and produces a nanofibers which is deposited in a form of a web on the oppositely charged collecting counter electrode placed at a distance.
Why is the process of electrospinning important?
- Cost effective
How it is done?
Electrospinning is carried out in laboratory by applying a high voltage to a polymer droplet suspended at the edge of a needle. The polymer droplet is fed with a polymer solution at a low flow rate. The voltage supplied must be high enough to create a Taylor cone and eject a fine jet of polymer from the droplet. The jet is collected on a grounded collector placed at a distance. The solvent is evaporated during its travel path from the needle to the collector. A deposition of nanofibers can be collected from the collector.
- To study the effect of different parameters like polymer, solvent, ambient parameters, voltage etc on nanofiber morphology.
- To control the ultimate nanofiber properties for organic polymeric fibers as well as inorganic nanofibers.
- Using there nanofibers for different application like tissue engineering, filtration, composits, electrical conducter etc.
- Scale up the process for various applications
We have been successful in producing nanofibers from a variety of polymeric and inorganic materials.
- Poly(acrylonitrile), Poly(vinyl alcohol), Poly(caprolactone), Gelatin, Poly(vinyl acetate) and cellulose acetate for organic nanofibers
- Zinc Oxide (ZnO), Ferric Oxide (Fe2O3) and Alumina (Al2O3) for Inorganic nanofibers
- Reproducibility of the nanofibers.
- Formation of bead free nanofibers especially when spinning fibres of diameter less than 100.
- Stabilization of process parameters for different polymeric as well as inorganic nanofiber for reproducible results. specially for inorganic nanofiber where calcination temperature has been found to have high importance.
- Overcoming problems of nonuniform web formation on applying multi syringe and needle-less systems.
- To produce defect free nano fibre webs consistently for continuous production.
- Effect of parameters on nanofibre properties for several polymeric nanofibers like PCL, PVA, PAN, Gelatin, PVAc etc as well as some inorganic nanofiber like Zinc Oxide (ZnO), Ferric Oxide (Fe2O3) and Alumina (Al2O3) have been studied and established.
- Apart from conventional mats, electrospun materials in the form of self assembled yarns and bulky non-woven structures have been produced.
- Uniform deposition of nanofibers in a continuous manner.
- Patented (patent pending) technology for continuously producing nanofibre webs at production rate of about 0.1-0.5 GSM at a collector speed of up to 3 m/min.