Invented waterproof fabric

Even the best raincoats still absorb water after about two months of use. But a new material invented by Swiss chemists could help build a challenging coat with liquids.

A drop of water comes into contact with the silicone fiber in spherical form and will roll if the fabric is tilted at least 2 degrees from the horizontal.Photo: Newscientist.

Experts from the University of Zurich say they create new materials by coating millions of silicone fibers on larger sized polyester fibers. When exposed to this fabric, water droplets exist in spherical form and people just need to tilt the cloth 2 degrees from the horizontal so that they roll away like marbles. Millions of drops of water can come and go away from the cloth for hours and hours without leaving any trace.

Millions of silicone fibers have a diameter of 40 nanometers (40 billionths of a meter) and are arranged in a structure similar to tiny cotton fibers that have waterproof properties that help the new fabric to challenge the liquid. The same type of water-resistant structure also exists in many animals and plants in nature, such as the surface of the lotus leaf.

A stream of water flows into the cloth but leaves no trace.Photo: Newscientist.

Due to its cotton-like appearance, tiny silicone fibers can hold air, creating a permanent layer of air that prevents water from coming into contact with polyester fibers. Some insects and spiders also use the same structure to breathe underwater. The new material can maintain dry state even when dipped in water for two months.

The process of making new waterproof materials is quite simple. Experts influence silicone in the form of gas to condense into tiny sized fibers. Such silicone fibers can be added to many other fibers, such as wool, cotton, but polyester is the most suitable yarn.

Tests show that new materials are relatively durable. Unlike many types of water-proof materials, it maintains its shape even when the fibers are strongly rubbed. Of course, it still deforms if thrown into the washing machine everyday.