An ultra-fine nonwoven fabric produced by electrospinning.

Electrospinning creates ultra-fine fibres for many applications

Experimental textiles produced by electrospinning are being assessed for medical, industrial and environmental applications.

• 20 January 2009 | Updated 14 October 2011

• What is electrospinning?
• Wound care
• Fine particle air filtration
• Water purification
• About the scientist

What is electrospinning?

Conventional fibre spinning techniques such as melt spinning, dry and wet spinning rely on mechanical forces to produce fibres. This is done by extruding polymer melt or solution through a spinneret and subsequently drawing the resulting filaments as they solidify or coagulate.

Electrospinning is a simple and versatile method for producing ultra-fine fibres from a variety of materials, including polymers, composites and ceramics.

In the presence of a strong electric field, an electrostatic charge is introduced to a fine stream of polymer solution directed at a grounded collector plate.

The electrically charged jet of polymer solution accelerates and thins out in the electric field. If a solvent is present it usually evaporates before the filament reaches the collector plate.

Dr Yen Truong leads CSIRO’s electrospinning project in association with research teams investigating:

• medical textiles for wound care, nerve regeneration and tissue culture
• air filtration for the removal of extremely fine particles
• water treatments for the removal of metals such as cadmium.

Dr Truong’s research at CSIRO Materials Science and Engineering (CMSE) on tissue culture includes collaboration with researchers in CSIRO Molecular Health Technologies (CMHT) in studies of cell adhesion to electrospun membranes with different fibre orientations.

Dr Truong also supplies electrospun textiles to a CSIRO project on flexible electronics that can be integrated into clothing fabric.

The scanning electron microscope image below depicts at knitted textile structure overlaid with ultra-fine electrospun fibres, which will be used as a textile scaffold for tissue culture.

A SEM image of knitted structure with an overlay of electrospun fibres for use in tissue engineering.

Wound care

CSIRO is studying electrospun polyurethane membranes for wound care. These membranes have good barrier properties, oxygen permeability and mechanical strength.

Permeability to water is also an important property, to prevent fluid build-up between the skin and the wound cover. Dr Truong’s team has improved permeability using ultra-violet light and ozone to modify the wettability of the membranes, without damaging the fibres.

Currently the team is studying chemical and physical changes in the membranes as they age.

Fine particle air filtration

Low cost filters that capture fine particles (below 1 micrometre) efficiently are required for protection from poor air quality and hazardous emissions.

Electrospun membranes are typically very light (0.003 gsm) and efficient but require support from another component, such as paper, woven or knitted structures.

The research team is investigating the properties of composite filters made from an electrospun fibre membrane attached to a paper base.

The properties investigated included filtration efficiency and pressure drop, for the critical range of particle sizes between 0.1 and 1.0 micrometre diameter. These particles are the most difficult to capture and the most hazardous to humans.

Water purification

Dr Truong’s group is investigating the capacity of electrospun membranes to bind metals, such as cadmium.

The researchers use polyvinylidene fluoride electrospun membranes, incorporating a commercial extraction reagent, for removing cadmium from hydrochloric acid solutions.

Preliminary studies indicated that these membranes have the potential to remove cadmium from the solutions. Further work is under way to investigate the robustness of the membranes and their suitability for environmental and wastewater clean-up.

About the scientist

Dr Truong collaborates with researchers in CSIRO Molecular Health Technologies in studies of cell adhesion to electrospun membranes with different fibre orientations.

Read more about Dr Yen Truong: investigating textiles created by electrospinning.