Vorlesen Engineers at the Massachusetts Institute of Technology (MIT) at Cambridge have developed a highly oil-repellent fabric. Liquids with low surface tension, such as hydrocarbons, simply bead off the surface. Responsible for this are the chemical properties of the material and its special surface finish. In nature, there are no highly oil-repellent surfaces, whereas there are a number of materials that repel water, such as leaves. The effect responsible for this behavior is due to the difference in the surface tension of the liquids. Water has a high surface tension and forms drops that roll off, for example, on a freshly waxed car. Oil and other hydrocarbons have a low surface tension and spread on surfaces. Therefore, water pearls off bird feathers, but oil can only be removed from the feathers with a solvent.
The researchers solved this problem of surface tension with a material made of special microfibers, which cause drops of liquid to bead off. The synthetic fibers include the synthetic FluoroPOSS molecule, which has extremely low surface energy. The rough material also has structures of tiny troughs and columns, which contribute to the repulsive effect by the resulting concave forms.
The scientists can use the fiber to construct fabrics that repel various hydrocarbons and, for example, separate certain hydrocarbons from water. Also, the fibers can be applied to different surfaces, such as metal, glass, plastics or even organic surfaces such as leaves. The technology could find application in aerospace components that should never be soaked in oil or fuel.
Anish Tuteja (Massachusetts Institute of Technology, Cambridge) et al .: Science, Vol. 318, p. 1618 ddp / science.de? Gesa Graser display