Oil repeller

MIT engineers have designed a class of material structures that can repel oils, a novel discovery that could have applications in aviation, space travel and hazardous waste cleanup. Such materials could be used to help protect parts of airplanes or rockets that are vulnerable to damage from being soaked in fuel, like rubber gaskets and o-rings.

Creating a strongly oil-repelling, or 'oleophobic' material, has been challenging for scientists, and there are no natural examples of such a material.

'Nature has developed a lot of methods for waterproofing, but not so much oil-proofing,' said Gareth McKinley, MIT School of Engineering Professor of Teaching Innovation in the Department of Mechanical Engineering and a member of the research team. 'The conventional wisdom was that it couldn't be done on a large scale without very special lithographic processes.'

The tendency of oils and other hydrocarbons to spread out over surfaces is due to their very low surface tension - a measure of the attraction between molecules of the same substance.