Cellulose diacetate, sometimes called diacetate, is a synthetic polymer made by treating cellulose with acetic acid.

It consists of two acetyl functional groups on each unit of D-anhydroglucopyranose of the cellulose molecule.

When cellulose diacetate deteriorates, it shrinks and releases acetic acid causing vinegar syndrome.

Cellulose diacetate has been used to make fabrics, membranes, filaments, and many consumer products.

Cellulose diacetate is hydrophilic[2] and biodegradable.