Page 213 - Chemical and process design handbook

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CELLULOSE ACETATE

Fully acetylated cellulose is partly hydrolyzed to give an acetone-soluble
product, which is usually between the di- and triester. The esters are mixed
with plasticizers, dyes, and pigments and processed in various ways,
depending upon the form of plastic desired.
Cellulose acetate is moldable, in contrast to cellulose nitrate, which is
not. It, however, has poor resistance to moisture. To overcome this disad-
vantage, treating the cotton linters with a mixture of butyric acid, acetic
acid, and acetic anhydride produces a mixed acetate-butyrate. The plastics
made from this material have better moisture resistance and better dimen-
sional stability than cellulose acetate. They also have excellent weathering
resistance, high impact strength, moldability, and high dielectric strength.

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