Cuprammonium rayon is a

rayon Rayon, also called viscose and commercialised in some countries as sabra silk or cactus silk, is a semi-synthetic fiber made from natural sources of regenerated cellulose fiber, cellulose, such as wood and related agricultural products. It has t ...

fiber made from

cellulose Cellulose is an organic compound with the chemical formula, formula , a polysaccharide consisting of a linear chain of several hundred to many thousands of glycosidic bond, β(1→4) linked glucose, D-glucose units. Cellulose is an important s ...

dissolved in a cuprammonium solution,

Schweizer's reagent Schweizer's reagent is a metal ammine complex with the formula salt consists of tetraamminediaquacopper(II) cations () and hydroxide anions (). It is prepared by dissolving copper(II) hydroxide in an aqueous solution of ammonia. It forms an azu ...

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

copper Copper is a chemical element; it has symbol Cu (from Latin ) 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-orang ...

and

ammonia Ammonia is an inorganic chemical compound of nitrogen and hydrogen with the chemical formula, formula . A Binary compounds of hydrogen, stable binary hydride and the simplest pnictogen hydride, ammonia is a colourless gas with a distinctive pu ...

with

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

. The solution is passed through a

spinneret A spinneret is a silk-spinning organ of a spider or the larva of an insect. Some adult insects also have spinnerets, such as those borne on the forelegs of Embioptera. Spinnerets are usually on the underside of a spider's opisthosoma, and ar ...

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 suit jacket linings as well as lightweight summer dresses and blouses, sometimes in combination with

cotton Cotton (), first recorded in ancient India, 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 ...

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 graduated scientist trained in the study of chemistry, or an officially enrolled student in the field. Chemists study the composition of ...

Matthias Eduard Schweizer Matthias Eduard Schweizer (8 August 1818 – 23 October 1860) was a Swiss people, Swiss chemist who in 1857 invented Schweizer's reagent, in which cellulose can be dissolved to produce artificial silk or rayon. He was one of the pioneers of the sy ...

(1818–1860) discovered that cellulose dissolves in tetraaminecopper dihydroxide.

Max Fremery Max Fremery (29 March 1859 – 1 March 1932) was a German chemist and industrialist. He was one of the founders of the (VGF) in 1899. VGF became a major manufacturer of artificial fibers. Early years (1859–85) Fremery was born in Cologne on 2 ...

and

Johann Urban Johann Urban (or Johannes Urban, 7 June 1863 – 13 November 1940) was an Austrian chemist and industrialist. He was one of the pioneers of the artificial silk industry. Early years Johann Urban was born on 7 June 1863 in Wuchern (now Vuhred) nea ...

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 comp ...

s for use in

light bulb Electric light is an artificial light source powered by electricity. Electric Light may also refer to: * Light fixture, a decorative enclosure for an electric light source * ''Electric Light'' (album), a 2018 album by James Bay * Electric Light ( ...

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

textiles Textile is an Hyponymy and hypernymy, umbrella term that includes various Fiber, fiber-based materials, including fibers, yarns, Staple (textiles)#Filament fiber, filaments, Thread (yarn), threads, and different types of #Fabric, fabric. ...

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 B ...

in Oberbruch near

Aachen Aachen is the List of cities in North Rhine-Westphalia by population, 13th-largest city in North Rhine-Westphalia and the List of cities in Germany by population, 27th-largest city of Germany, with around 261,000 inhabitants. Aachen is locat ...

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

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

's predecessor. An improvement by

J. P. Bemberg AG J. P. Bemberg was a German rayon manufacturer that produced an unusually fine artificial fiber which became known as ''Bemberg''. J. P. Bemberg came under the control of Vereinigte Glanzstoff-Fabriken and eventually disappeared after a series of me ...

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 fiber, natural protein fiber, some forms of which can be weaving, woven into textiles. The protein fiber of silk is composed mainly of fibroin and is most commonly produced by certain insect larvae to form cocoon (silk), c ...

-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 structural unit, 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 polymeriza ...

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 Extrusion is a process used to create objects of a fixed cross-sectional profile by pushing material through a die of the desired cross-section. Its two main advantages over other manufacturing processes are its ability to create very complex ...

into

sulfuric acid Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid (English in the Commonwealth of Nations, Commonwealth spelling), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen, ...

References

External links

A demonstration of the cuprammonium rayon process

Synthetic fibers Cellulose Products introduced in 1890 {{fashion-stub