Nitrocellulose (NC), also called cellulose nitrate, is the oldest thermoplastic. It was invented by Alexander Parkes in 1855 and later commercialized under the trademarks Parkesine, Xylonite and Celluloid. It is synthesized by reacting cellulose fibers with an aqueuos solution of nitric and sulfuric acid. The average degree of nitration will be affected by the water content, composition of the bath, immersion time, and reaction condition. NC's with about 2 nitrate groups per glucose repeat unit are often chosen in plastics and laquers. A higher nitrate content is used in explosives.
Plastics made from NC have excellent mechanical properties including high impact resistant but have poor weathering and heat stability and are not resistant to dilute acids and bases, but are insoluble and stable in water and nonpolar solvents. To achieve the desired properties, other additives such as camphor, dyes, stabilizers and fillers are often added.
Nitrocellulose is highly combustable which makes it too hazardous for
many applications. Today, NC is mainly used as an inexpensive binder in products like (flexographic) printing inks,
fast drying lacquers, baked-on enamels, and adhesives.1
In several of these applications, NC is modified (reacted) with other
resins such as alkyd and amino resins.
The dilution with other ingredients such as camphor greatly reduces the flammability of NC. This
blend is called celluloid. It is used for handles of fountain pens, tools and brushes; for eyeglass frames; and in the past, for motion picture film.
1The nitrocellulose market is expected to reach US$ 940 million by the year 2023, growing at a CAGR of about 7%. Source: Global Market Insight, May 9, 2017