Materials engineers at the University of Florida have designed a surface that repels water almost as well as spiders repel some people. To create a “nearly perfect hydrophobic surface,” says Professor Wolfgang Sigmund, he and his research staff reproduced the length and distribution of tiny hairs that grow on spiders’ bodies with microscopic plastic fibers.
Scientists have long observed that water rolls off arachnids in nearly perfect spheres, demonstrating that their bodies are relatively frictionless with water. To Sigmund’s surprise, water behaved identically on his surface modeled after the spider. Whereas most water-repellent materials are chemical-based and toxic, the new surface employs physics to do the same job. The surface relies entirely on the shape and random distribution of the plastic fibers rather than on its chemical composition. The researchers have received interest from commercial industry because the surface is the first to repel hot water, cold water, and—if the chemical makeup is changed slightly—water and oil simultaneously.
Practical applications might include covering pots and pans to make them non-stick, surfacing the inside of water pipes to reduce the power consumption of pumps, and coating the hulls of boats to reduce lag from friction. But Sig- mund and his team are still in the preliminary stages of improving the material’s functionality and resistance to damage. “We don’t want people to look at cars with our surface and think ‘It needs a haircut,’” he says.
