A Comparison of the Chemical Structures and Production Methods of Silk

A Comparison of the Chemical Structures and Production Methods of Silk and Artificial Silk Abstract Despite their seemingly similar exteriors, the chemical structures and production methods of natural silk and the artificial silks rayon and nylon are quite different. Silk yarn, extracted from the cocoon of the Bombyx mori moth, is made up of fibroin molecules with beta-pleated sheet secondary structures. The fibroin molecules consist of crystalline fibers constructed of regularly paralleled, unfolded polypeptide chains of polyglycylalanine mixed with an amorphous part. Although viscose rayon was originally called â€Å"artificial silk,† it is not a truly synthetic fiber, as it is made from wood pulp, a naturally-occurring, cellulose-based material. Nylon, however, is a synthetic fiber. It is a polyamide whose molecular chains are formed by regularly spaced –CONH– amide groups. Nylon 6-6, or poly(hexamethylneadipamide), is composed of two structural monomers (hexamethylendiamine (H2N(CH2)6NH2) and adipic acid (HOOC(CH2)4COOH), whereas Nylon 6, or poly(6-caprolactam), is composed of a single structural unit (either 6-aminocaproic acid (H2N(CH2)4COOH) or caprolactam). Ultimately, the different chemistries and production methods of these fibers give them certain advantages (such as viscose’s ability to combine with other fibers to create new fabrics easily) and disadvantages (such as nylon’s quickly weakening fibers or natural silk’s difficulty of production) over one another that make them more or less suitable for certain purposes. For this reason, when considering silk and artificial silk, it is illogical to pick one fiber that is superior to the others and to focus on the production of that specific fiber. A Compa... ...io State University Extension Fact Sheet: Textiles and Clothing. Retrieved July 25, 2008, from http://ohioline.osu.edu/hygfact/ 5000/5538.html Swicofil AG Textile Services. (n.d.). Viscose Rayon. Swicofil. Retrieved July 25, 2008, from http://www.swicofil.com/viscose.htmlc Trossarelli, L. (2003). The History of Nylon. Commissione Centrale Materiali e Tecniche. Retrieved July 25, 2008, from http://www.caimateriali.org/Eventi/Torino/historynylon.html The Viscose Company. (1937). The Story of Rayon (3rd ed.). New York Sales Office: 200 Madison Avenue: The Viscose Company. Wikipedia. (July 24, 2008). Silk. Retrieved July 28, 2008, from http://en.wikipedia.org/wiki/Silk Wikipedia. (July 28, 2008) Viscose. Retrieved July 26, 2008, from http://en.wikipedia.org/wiki/Viscose Woodhouse, T. F. (1929). Artificial Silk or Rayon (2nd ed.). Sir Isaac Pitman & Sons, Ltd.