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The most common form of cellulose acetate fiber has an acetate group on approximately two of every three hydroxyls. This cellulose diacetate is known as secondary acetate, or simply as "acetate". After it is formed, cellulose acetate is dissolved in acetone, forming a viscous solution for extrusion through spinnerets (which resemble a shower ...
These are washed mechanically and chemically to remove proteins, waxes, pectins and other polysaccharides. This is bleached to get the required brightness. Dissolving pulp from cellulose linters gives the purest cellulose and is used to manufacture acetate plastics and high-viscosity cellulose ethers. [2]
Cellulose, which is quite insoluble in water (hence its utility as clothing), dissolves in the presence of Schweizer's reagent. Using the reagent, cellulose can be extracted from wood pulp, cotton fiber, and other natural cellulose sources. Cellulose precipitates when the solution is acidified. It functions by binding to vicinal diols. [3]
Triacetate is derived from cellulose by acetylating cellulose with acetic acid and/or acetic anhydride. Acetylation converts hydroxyl groups in cellulose to acetyl groups, which renders the cellulose polymer much more soluble in organic solvents. The cellulose acetate is dissolved in a mixture of dichloromethane and methanol for spinning.
Lacquer thinner, also known as cellulose thinner, is usually a mixture of solvents able to dissolve a number of different resins or plastics used in modern lacquer. [ 1 ] Previously, lacquer thinners frequently contained alkyl esters like butyl or amyl acetate , ketones like acetone or methyl ethyl ketone , aromatic hydrocarbons like toluene ...
The most common way to prepare cellulose acetate phthalate consists of the reaction of a partially substituted cellulose acetate (CA) with phthalic anhydride in the presence of an organic solvent and a basic catalyst. The organic solvents widely used as reaction media for the phthaloylation of cellulose acetate are acetic acid, acetone, or ...
Reactive dyes are by far the best choice for dyeing cotton and other cellulose fibers at home or in the art studio. Disperse dyes were originally developed for the dyeing of cellulose acetate, and are water-insoluble. The dyes are finely ground in the presence of a dispersing agent and sold as a paste, or spray-dried and sold as a powder.
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 suit jacket linings as well as lightweight summer dresses and blouses, sometimes in combination with cotton to ...