Friday

Ch. 6: Silk and Nylon

The properties of silk that made it so popular, its smoothness, its luster, and it suitability for a variety of climates are due to its Chemical Composition. It is because of Silk's chemical structure that it was so widely coveted and traded. (Le Couteur & Burreson 105-122)

Silk was first discovered by the Chinese in c.2600 BCE. Princess Hsi-ling-shih first learned of this valuable thread when an insect cocoon fell into her tea and she realized that the silk could be unwound and was viable for textile use. The cocoon that fell into the Chinese Princess's tea was a silkworm's (Bombyx mori) cocoon. Ever since then, silk has been obtained from the silkworm. In order to harvest the silk, the silkworm cocoons must be heated to kill the chrysalis inside and then boiled in water to dissolve a sticky secretion that was produced b the silkworm to hold the silk threads together. Pure silk is then unwound from the cocoons and spun onto reels. Over the next 200 years, the silk trade flourished. The production of silk was a heavily guarded Chinese secret, but eventually the method of silk production spread to other countries and started new industries throughout the Mediterranean and East Asia. (Le Couteur & Burreson 105-122)

These silkworms will soon spin themselves into a cocoon made of silk.
(wikimedia.org)

Silk is a protein that is composed of 22 amino acids. The amino acids, glycine, alanine, and serine alone account for 85% of silk's structure. The size of the amino acids play an important factor in determining the smoothness of the silk. The structure of silk forms a pleated pattern. This pleated structure is responsible for many of silk's desirable properties such as its resistance to stretching, smoothness, and luster.(Le Couteur & Burreson 105-122)

Nylon was discovered in the mid-20th century by Wallace Carothers. Nylon generally serves as an artificial, and cheaper silk. It was made by combining the adipic acid molecule with the 1,6 diaminohexane molecule. Nylon and Silk are chemically similar in the fact that they both contain an aminde link formed by eliminating a water molecule. Nylon is best known for its use in women's' hosiery, but it was also used as toothbrush bristles, fishing lines and nets, for surgical sutures, and for coating electrical wires. When WWII struck most nylon production was diverted for military use and made into tire chords, mosquito nets, weather balloons, rope, or parachute shrouds. (Le Couteur & Burreson 105-122)

Silk made an impression on history by allowing for the growth of international trade, established new industries, and brought great wealth to many parts of the globe.(Le Couteur & Burreson 105-122)