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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 ...
Cellulose acetate film, or safety film, ... Cellit was a stable, non-brittle cellulose acetate polymer that could be dissolved in acetone for further processing.
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]
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 ...
Cellulose acetate is also known as "safety" film and started to replace nitrate film in still photography in the 1920s. [1] There are several types of acetate that were produced after 1925, which include diacetate (c. 1923 – c. 1955), acetate propionate (1927 – c. 1949), acetate butyrate (1936–present), and triacetate (c. 1950 – present). [1]
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 ...
However, the more general model in gas applications is the solution-diffusion (d) where particles are first dissolved onto the membrane and then diffuse through it both at different rates. This model is employed when the pores in the polymer membrane appear and disappear faster relative to the movement of the particles. [5]