Cuprammonium rayon is a

rayon Rayon is a semi-synthetic fiber, made from natural sources of regenerated cellulose, such as wood and related agricultural products. It has the same molecular structure as cellulose. It is also called viscose. Many types and grades of viscose ...

fiber made from

cellulose Cellulose is an organic compound with the formula , a polysaccharide consisting of a linear chain of several hundred to many thousands of β(1→4) linked D-glucose units. Cellulose is an important structural component of the primary cell wall ...

dissolved in a

cuprammonium Schweizer's reagent is the metal ammine complex with the formula u(NH3)4(H2O)2OH)2. This deep-blue compound is used in purifying cellulose. It is prepared by precipitating copper(II) hydroxide from an aqueous solution of copper sulfate using ...

solution,

Schweizer's reagent Schweizer's reagent is the metal ammine complex with the formula u(NH3)4(H2O)2OH)2. This deep-blue compound is used in purifying cellulose. It is prepared by precipitating copper(II) hydroxide from an aqueous solution of copper sulfate using ...

. It is produced by making cellulose a soluble compound by combining it with

copper Copper is a chemical element with the symbol Cu (from la, cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish ...

and

ammonia Ammonia is an inorganic compound of nitrogen and hydrogen with the formula . A stable binary hydride, and the simplest pnictogen hydride, ammonia is a colourless gas with a distinct pungent smell. Biologically, it is a common nitrogeno ...

with

caustic soda Sodium hydroxide, also known as lye and caustic soda, is an inorganic compound with the formula NaOH. It is a white solid ionic compound consisting of sodium cations and hydroxide anions . Sodium hydroxide is a highly caustic base and alkal ...

. The solution is passed through a spinneret and the cellulose is regenerated in hardening baths that remove the copper and ammonia and neutralize the caustic soda. Cuprammonium rayon is usually made in fine filaments that are used in lightweight summer dresses and blouses, sometimes in combination with

cotton Cotton is a soft, fluffy staple fiber that grows in a boll, or protective case, around the seeds of the cotton plants of the genus '' Gossypium'' in the mallow family Malvaceae. The fiber is almost pure cellulose, and can contain minor p ...

to make textured fabrics with slubbed, uneven surfaces. The fabric is commonly known by the trade name "Bemberg", owned by the J.P. Bemberg company. The fabric may also be known as "cupro" or "cupra". It is also known as "ammonia silk" on Chinese fashion retail websites.

History

Cuprammonium rayon was invented in 1890. Swiss

chemist A chemist (from Greek ''chēm(ía)'' alchemy; replacing ''chymist'' from Medieval Latin ''alchemist'') is a scientist trained in the study of chemistry. Chemists study the composition of matter and its properties. Chemists carefully describe ...

Matthias Eduard Schweizer (1818–1860) discovered that cellulose dissolves in tetraaminecopper dihydroxide. Max Fremery and Johann Urban developed a method to produce

carbon fiber Carbon fiber-reinforced polymers (American English), carbon-fibre-reinforced polymers (Commonwealth English), carbon-fiber-reinforced plastics, carbon-fiber reinforced-thermoplastic (CFRP, CRP, CFRTP), also known as carbon fiber, carbon compo ...

s for use in

light bulb An electric light, lamp, or light bulb is an electrical component that produces light. It is the most common form of artificial lighting. Lamps usually have a base made of ceramic, metal, glass, or plastic, which secures the lamp in the so ...

s in 1897 (the factory closed in 1902). Production of cuprammonium rayon for

textiles Textile is an umbrella term that includes various fiber-based materials, including fibers, yarns, filaments, threads, different fabric types, etc. At first, the word "textiles" only referred to woven fabrics. However, weaving is not th ...

started in 1899 in the

Vereinigte Glanzstoff Fabriken AG Vereinigte Glanzstoff-Fabriken (VGF, United Rayon Factories) was a German manufacturer of artificial fiber founded in 1899 that became one of the leading European producers of rayon. During the first thirty years VGF cooperated closely with the Br ...

in Oberbruch near Aachen.''Verinigte Glanstoff Fabriken'' merged with the ''Nederlandse Kunstzijdefabrieken'' in 1929 to form the ''Algemene Kunstzijde Unie'',

AkzoNobel Akzo Nobel N.V., stylized as AkzoNobel, is a Dutch multinational company which creates paints and performance coatings for both industry and consumers worldwide. Headquartered in Amsterdam, the company has activities in more than 80 countries ...

's predecessor. An improvement by J. P. Bemberg AG in 1904 made the artificial silk a product comparable to real silk.''J. P. Bemberg AG'' was one of the '' Vereinigte Glanzstoff-Fabriken'' which merged into the Dutch based ''Algemene Kunstzijde Unie'' (AKU)--

today.

Properties

* The fibers are very fine * It has a soft,

silk Silk is a natural protein fiber, some forms of which can be woven into textiles. The protein fiber of silk is composed mainly of fibroin and is produced by certain insect larvae to form cocoons. The best-known silk is obtained from the ...

-like handle (i.e., tactile feel) * It has similar properties to cotton. It is different in that the average

degree of polymerization The degree of polymerization, or DP, is the number of monomeric units in a macromolecule or polymer or oligomer molecule. For a homopolymer, there is only one type of monomeric unit and the ''number-average'' degree of polymerization is given by D ...

is lower and a larger part of this fiber is occupied by amorphous regions, causing cuprammonium rayon to swell * It burns rapidly and chars at 180°C * On ignition, it leaves behind ash containing copper * It can be used to create fabric that is sheer and lightweight and has desirable draping properties

Production

Cellulose is dissolved in a u(NH₃)₄OH)₂ solution and then regenerates as rayon when extruded into sulfuric acid.

References

Synthetic fibers Cellulose {{fashion-stub