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The invention of nylon
1. In 1928 a team of researchers, led by organic chemist Wallace H. Carothers of the United States and sponsored by the chemical firm, set out to discover what sorts of materials they could produce from varying combinations of long-chain molecules. In a pioneering process called polymerization they combined atoms into long molecules that varied in the types of atoms used and the ways they were joined, producing an assortment of unique materials.
2. Then one day in 1930 they discovered an unusual property of one of their molten substances: it would stick to a glass rod and form a fine strand. As soon as the strand met the cold air, it solidified and formed a long continuous fiber that was both flexible and strong. If the fiber was then stretched to four or five times its original length, its properties changed further: it strengthened still more and at the same time became lustrous. Its structure was such that it could be spun into a fiber resembling silk, but it had high strength and elasticity and exceptional resistance to abrasion, rot, mildew, and chemicals.
3. For eight years chemists, physicists, engineers, and textile experts labored to develop this oddity into a usable fiber that could be manufactured on a large scale. In 1938 they announced their success. This synthetic textile fiber was to be called nylon.
Ответьте на вопрос:
What are the unique properties of nylon?
It resembles silk that is why it became so popular among manufacturers.
It becomes solid, opaque and rigid when it meets cold air or extreme heat.
The structure of a nylon thread is rather flexible so it resembles silk.
It is strong, flexible and does not lose its properties being vigorously stretched.
