Question

Evaluate which is better cotton or nylon, wool or rayon in terms of its properties?

Answer 1

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Rayon is a manufactured fiber made from regenerated cellulose fiber. The many types and grades of rayon can imitate the feel and texture of natural fibers such as silk, wool, cotton, and linen. The types that resemble silk are often called artificial silk.
Rayon is made from purified cellulose, primarily from wood pulp, which is chemically converted into a soluble compound. It is then dissolved and forced through a spinneret to produce filaments which are chemically solidified, resulting in fibers of nearly pure cellulose.
Because rayon is manufactured from naturally occurring polymers, it is considered a semisynthetic fiber, whereas in precise usage the term synthetic fiber is sometimes reserved for the fully synthetic fibers. Specific types of rayon include viscose, modal and lyocell, each of which differs in manufacturing process and properties of the finished product.
Workers can be seriously harmed by the carbon disulphide used to make most rayon.
RAYON AND ITS VARIATIONS
Nitrocellulose
The solubility of nitrocellulose in organic solvents such as ether and acetone was the basis for the first "artificial silk" by Georges Audemars in about 1855. Commercial production started in 1891, but the result was flammable and more expensive than cellulose acetate or Cuprammonium rayon. Because of this expense, production ceased early in the 1900s. Nitrocellulose was briefly known as "mother-in-law silk". Frank Hastings Griffin invented the double-godet, a special stretch-spinning process that changed artificial silk to rayon, rendering it usable in many industrial products such as tire cords and clothing. Nathan Rosenstein invented the "spunize process" by which he turned rayon from a hard fiber to a fabric. This allowed rayon to become a popular raw material in textiles.
Acetate method
Paul Schützenberger discovered that cellulose reacts with acetic anhydride to form cellulose acetate. The triacetate is soluble only in chloroform making the method expensive. The discovery that hydrolyzed cellulose acetate is soluble in more polar solvents, like acetone, made production of cellulose acetate fibers cheap and efficient.
Cuprammonium method
The Swiss chemist Matthias Eduard Schweizer (1818–1860) discovered that cellulose dissolved in tetraamminecopper dihydroxide. Max Fremery and Johann Urban developed a method to produce carbon fibers for use in light bulbs in 1897. Production of Cuprammonium rayon for textiles started in 1899 in the Vereinigte Glanzstoff Fabriken AG in Oberbruch near Aachen. Improvement by the J. P. Bemberg AG in 1904 made the artificial silk a product comparable to real silk.


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