Rayon acetate

The cellulose molecule contains three hydroxyl groups which can react and leave the chain backbone intact. These alcohol groups can be esterified with acetic anhydride to form cellulose acetate. This polymer is spun into the fiber acetate rayon. Similarly, the alcohol groups in cellulose react with CS2 in the presence of strong base to produce cellulose xanthates. When extruded into fibers, this material is called viscose rayon, and when extruded into sheets, cellophane. In both the acetate and xanthate formation, some chain degradation also occurs, so the resulting polymer chains are shorter than those in the starting cellulose. 

Odon acetate Odon, Saran polyethylene Teflon steel wood amber sealing wax hard mbber nickel, copper, brass, silver, old platinum sulfur acetate rayon polyester... 

Cellulose acetate [9004-35-7], prepared by reaction of cellulose with acetic anhydride, acetic acid, and sulfuric acid, is spun into acetate rayon fibers by dissolving it in acetone and spinning the solution into a column of warm air that evaporates the acetone. Cellulose acetate is also shaped into a variety of plastic products, and its solutions are used as coating dopes. Cellulose acetate butyrate [9004-36-8], made from cellulose, acetic anhydride, and butyric anhydride in the presence of sulfuric acid, is a shock-resistant plastic. 

Acetate rayon dyes developed for cellulose acetate and some synthetic fibers. 

Acetat-kimstseide,/. = Acetatseide. -Ifisung,/ acetate solution, -seidet /. acetate silk (acetate rayon). -zellwoUet /. acetate spun rayon. 

Viskositats-messer, m. viscosimeter, viscometer. -zahl,/. viscosity number or value. Vistra. Viatra (an acetate rayon). T.N. visuell, a. visual. 

Nature uses cellulose primarily as a structural material to impart strength and rigidity to plants. Leaves, grasses, and cotton, for instance, are primarily cellulose. Cellulose also serves as raw material for the manufacture of cellulose acetate, known commercially as acetate rayon, and cellulose nitrate, known as guncotton. Guncotton is the major ingredient in smokeless powder, the explosive propellant used in artillery shells and in ammunition for firearms. 

This term was originally intended to denote all kinds of man-made textile fibres, but is now applied only to cellulose types. Viscose rayon (regenerated from a solution of cellulose xanthate in sodium hydroxide) accounts for the greater part of world rayon production. Acetate rayon and cuprammonium rayon are relatively unimportant. 

Uses Manufacture of acetate rayon, acetic anhydride, acetone, acetyl compounds, cellulose acetates, chloroacetic acid, ethyl alcohol, ketene, methyl ethyl ketone, vinyl acetate, plastics and rubbers in tanning laundry sour acidulate and preservative in foods printing calico and dyeing silk solvent for gums, resins, volatile oils and other substances manufacture of nylon and fiber, vitamins, antibiotics and hormones production of insecticides, dyes, photographic chemicals, stain removers latex coagulant textile printing. 

Cellulose derivatives as cellulose acetate (rayon) and cellulose nitrate, etc. are the usual examples of this sub category. 

Uses. Solvent in the manufacture of dyes, plastics, and cellulose acetate rayon anesthetic agent... 

The basic cellulose unit contains three hydroxyl groups. The triester cellulose triacetate forms when cellulose is reacted with glacial acetic acid. Hydrolysis removes some of the acetate groups to form a secondary ester, which averages about 2.4 acetyl groups per unit rather than three. The secondary ester is then dissolved in acetone and the solution ejected through a spinneret to form fibers. Cellulose acetate processed in this manner is referred to as acetate rayon, but it may be more commonly known by its trade name Celanese. 

The cuprammonia process, the viscose process, and the acetate process have been employed for the production of rayon. Cuprammonia and viscose rayons have similar chemical and physical properties. Both are easily dyed and lose their strength when wet because of a disruption of hydrogen bonding this wet strength is improved through chemical treatment of the rayon fabrics. Acetate rayon is readily softened in the ironing process and loses its luster in boiling water. 

Direct Oxidation. Direct oxidation of petroleum hydrocarbons has been practiced on a small scale since 1926 methanol, formaldehyde, and acetaldehyde are produced. A much larger project (29) began operating in 1945. The main product of the latter operation is acetic acid, used for the manufacture of cellulose acetate rayon. The oxidation process consists of mixing air with a butane-propane mixture and passing the compressed mixture over a catalyst in a tubular reaction furnace. The product mixture includes acetaldehyde, formaldehyde, acetone, propyl and butyl alcohols, methyl ethyl ketone, and propylene oxide and glycols. The acetaldehyde is oxidized to acetic acid in a separate plant. Thus the products of this operation are the same as those (or their derivatives) produced by olefin hydration and other aliphatic syntheses. 

As indicated, any given aliphatic chemical is likely to be made by a number of processes from several raw materials. Important examples are acetic anhydride and acetic acid (2) production of the former was about 900,000,000 pounds in 1950 and that of the latter was about half as great. The large demand for these related products is primarily the result of the requirements of cellulose acetate rayon for acetic anhydride. The economic complexities in the production of the aliphatic oxygenated chemicals are probably best illustrated by these two products. 

Twenty-five years ago the domestic supply of acetic acid came from the distillation of wood. This, in the form of calcium acetate, was reacted with acetyl chloride to produce acetic anhydride to satisfy the wants of the infant cellulose acetate rayon industry. Shortly thereafter a better process came on the scene utilizing the reactants sodium acetate, sulfur dichloride, and chlorine. 

Dinitro-2, 4-diamino-azobenzene, 02N.CgH4.N N.CgH2(N02)(NH2)2 orn-color-ed powd, colors acetate rayon a golden yel, was prepd by coupling 4-nitro-l, 3-diamino-benzene with 4-nitroaniline (Ref 1)... 

Amino-1,2,4-thiadiazoles79 and their 3-alkoxy-, 3-alkylmercapto-, and 3-dialkylamino derivatives84 have been claimed to be useful intermediates in the manufacture of dyes,84 pharmaceuticals,84 and materials valuable in pest control.79 Mono-azo dyes derived from diazotized 5-amino-l,2,4-thiadiazoles and coupling components of the benzene series are especially suitable for dyeing polymeric materials such as acetate rayon, polyamides, polyurethanes, polyesters, and... 

Further modification of the coumarin ring system in esculin (1) led to the development of 7-amino-4-methylcoumarins with an A-alkyl group at the 7-position. The sole representative of this series still on the market is 7-diethylamino-4-methylcoumarin (63) [91-44-1] [101], Despite its poor lightfastness, the good optical properties of this compound have kept it in use for the brightening of wool, cellulose acetate rayon, and polyamides. Compound 63 is produced by cyclocondensation of 3-diethylaminophenol with ethyl acetoacetate in the presence of zinc chloride [102],... 

Natural fibers such as cotton can be chemically modified to form rayon or acetate. Rayon was first called artificial silk. In the viscose process, cellulose is dissolved in sodium hydroxide, pushed through spinnerets, and treated with acid to harden. Treatment with copper compounds and ammonia is used to form hosiery yams. Acetate (or cellulose acetate), produced by treating cotton with acetic acid and acetic anhydride, is also used in production of clothing. 

Uses Methylamine is a colorless, fishlike-smelling gas at room temperature. It is used in a variety of industries such as manufacture of dyestuffs, treatment of cellulose, acetate rayon, fuel additive, rocket propellant, and leathertanning processes. 

Uses Dimethylamine is a colorless, inflammable gas at room temperature. It is used in the manufacture of several products such as detergent soaps, in leather tanning, in pharmaceutical manufacture, and for cellulose acetate rayon treatment. 

Used to make acetates, acetate plastics, acetate rayon, and as a solvent Skin is yellow where it comes in contact with the acid bums on the lips and mouth pain in the throat and stomach difficulty in swallowing nausea and vomiting feeble pulse diarrhea and collapse... 

Cellulose acetate has replaced cellulose nitrate in many products, for example, in safety-type photographic films. When a solution of cellulose acetate in acetone is passed through the fine holes of a spinneret and the solvent evaporates, solid filaments are produced. Acetate rayon is prepared from threads of these filaments. Some applications and solvents of commercial cellulose acetate grades are summarized in Table 9-5. 

Because acetylation of cellulose proceeds in a heterogeneous system, the reaction rate is controlled by the diffusion of the reagents into the fiber structure. The quality of the cellulose raw material used for acetate rayon is... 

Uses used to make acetates, plastics, acetate rayon, and as a solvent... 

CNC PYROBAN SF represents a very effective flame retardant for acetate and acetate/rayon blends. The product is also used for nylon and acrylic fabrics. 

Below the black thread at the top, the fibers are acetate rayon (cellulose di- or triacetate, SEF (Monsanto s modacylic), Amel (cellulose triacetate), cotton, Creslan (polyacrylonitrile). Dacron 54 and 64 (polyester without and with a brightener), nylon 6.6 (polyamide), Orion 75 (polyacrylonitrile), silk (polyamide), polypropylene, viscose rayon (regenerated cellulose), and wool (polyamide). 

Acetate rayon is cellulose (from any source) in which about two of the hydroxyl groups in each unit have been acetylated. This renders the polymer soluble in acetone from which it can be spun into fiber. The smaller number of hydroxyl groups in acetate rayon compared to cotton makes direct dyeing of rayon more difficult than of cotton. 

Fibers such as Dacron, acetate rayon, nylon, and polypropylene are difficult to dye with conventional dyes because they contain so few polar groups. These fibers are dyed with substances that are insoluble in water but that, at elevated temperatures (pressure vessels), are soluble in the fiber as true solutions. They are applied to the fiber in the form of a dispersion of finely divided dye (hence the name). The Cellitons are typical disperse dyes. 

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