Page 214 - Chemical and process design handbook

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CELLULOSE NITRATE

Fully nitrated cellulose (nitrocellulose) is unsuited for a plastic base
because of its extremely flammable character. Hence, a partly nitrated
product is made. Products containing 11% nitrogen are used for plastics,
12% nitrogen for lacquers, and the fully nitrated, or 13% nitrogen, mater-
ial is used for explosives.
In the process (Fig. 1), the cellulose nitrate is placed in large kneading
mixers with solvents and plasticizers and thoroughly mixed. The standard
plasticizer is camphor, and the compounded mixture is strained under
hydraulic pressure and mixed on rolls with coloring agents. The material
is pressed into blocks.
Finally, the plastic is made into sheets, strips, rods, or tubes, seasoned to
remove the residual solvent, and polished by pressing under low heat. This
plastic possesses excellent workability, water resistance, and toughness. Its
chief disadvantage is the ease with which it burns. It also discolors and
becomes brittle on aging. The trade name is Celluloid.

See Cellulose, Cellulose Acetate.

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