Plastic With Emotions

The plastic of the future will be a living material, which can change shape and move by means of light.

Ateam of scientists from the Eindhoven University of Technology in the Netherlands and the US Kent State University are staring intensely at a 2-cm-long, transparent plastic strip, which is lying on a table in front of them in their lab. Bathed in ultraviolet light from a lamp, it wriggles along like a caterpillar at a speed of 5 mm/second.

Although the motions of the plastic strip are slow, they are ground-breaking, as scientists have for the very first time managed to create a plastic material, which converts light into motion without the assistance of springs or other mechanics.

The light-sensitive plastic can be used in large solar cell parks, which generate power in remote places such as deserts. When the solar cells become covered in sand and dust, the sunlight is blocked out, reducing power generation. But when the solar cells are coated with transparent, flexible plastic film, they become self-cleaning. Scientists tested the system by sprinkling the strip with sand grains, which we r e

shaken off, and the strip was even able to carry objects of several times its own weight up a hill.

The plastic caterpillar is just one of many examples that a new generation of plastic with a wealth of new properties is coming up. The fantastic plastic of the future will be able to change its own properties according to the temperature and help dose medication in wound dressings.

PIONEER FACED WITH SCEPTICISM

The small plastic caterpillar enters the scene 110 years after the beginning of the era of modern plastic. In the summer of 1907, Belgian-American chemist Leo Baekeland created the world’s first synthetic plastic – phenolic plastic – which was named bakelite: a sturdy material, that does not conduct electricity. Bakelite soon became the favourite material for new electronic devices such as sockets, telephones, and radios. In a matter of a few years, the success of bakelite had caused a global plastic revolution.

However, chemists still disagreed about the basic structure of plastic. In a scientific article, German chemistry professor Hermann Staudinger in 1920 introduced his theory about macromolecules. He believed that huge