Researchers at the Ohio State University have discovered a way to manipulate tiny plastic fibres to create seemingly smooth surfaces that could be used in applications ranging from anti-fog technology to conducting electricity.
The scientists have created surfaces that appear flat and transparent as a sheet of glass, but on closer inspection, tiny fibres can be seen coating the surface.
The patent-pending technology involves growing a bed of fibres, tiny dots of polymer ‘seeds’ on a flat surface with vertical fibres coming out from the top of the seeds, until the scientists cut off the chemical reaction that modifies the fibres’ molecular structures, to form a ‘carpet’ of uniform height.
‘One of the good things about working with these polymers is that you’re able to structure them in many different ways,’ said Arthur Epstein, professor of chemistry and physics and director of Ohio State University’s Institute for Magnetic and Electronic Polymers. ‘Plus, we found that we can coat almost any surface with these fibres.’
Using the patent-pending technology, the scientists were able to create fibres that would either attract or repel certain substances, such as water and oil.
According to Epstein, windows coated with the repellant surface would stay cleaner for longer, as dirt, water and oil would not stick to the repellant fibres.
In contrast, the attracting fibres are said to make an effective anti-fog coating because they would pull at water droplets and spread out flat on the surface.
The researchers found that coiled strands of DNA reacted in the same way on repellant fibres, so that when droplets of water containing DNA were put on the fibres, the strands uncoiled and hung suspended from the fibres like clotheslines. Epstein said that the fibres could be used as a platform to study how DNA interacts with other molecules, and the spread-out DNA could be used for building new nanostructures.
Other applications of the nano-fibre surface included the conduction of electricity, as the scientists discovered that they could use the surface to charge an organic light-emitting device, and the control the flow of water in microfluidic devices.