Schönbein collaborated with the Frankfurt professor Rudolf Christian Böttger, who had discovered the process independently in the same year.īy coincidence, a third chemist, the Brunswick professor F. The cotton was then slowly dried at a temperature below 40 ☌ (104 ☏). After two minutes, the cotton was removed and washed in cold water to set the esterification level and to remove all acid residue. The method was to immerse one part of fine cotton in 15 parts of an equal blend of sulfuric acid and nitric acid. His preparation method was the first to be widely used. He hung the apron on the stove door to dry, and as soon as it was dry, a flash occurred as the apron ignited. He reached for the nearest cloth, a cotton apron, and wiped it up. As he was working in the kitchen of his home in Basel, he spilled a mixture of nitric acid (HNO 3) and sulfuric acid (H 2SO 4) on the kitchen table. Īround 1846 Christian Friedrich Schönbein, a German-Swiss chemist, discovered a more practical formulation. Jean-Baptiste Dumas obtained a similar material, which he called nitramidine. A few years later in 1838, another French chemist, Théophile-Jules Pelouze (teacher of Ascanio Sobrero and Alfred Nobel), treated paper and cardboard in the same way. In 1832 Henri Braconnot discovered that nitric acid, when combined with starch or wood fibers, would produce a lightweight combustible explosive material, which he named xyloïdine. Munitions History ĭeflagration test of nitrocellulose in slow motion In terms of lacquers, nitrocellulose dissolves readily in organic solvents, which upon evaporation leave a colorless, transparent, flexible film. The explosive applications are discussed below. The principal use of cellulose nitrate is for the production of explosives, lacquers, and celluloid. The yields are about 85%, with losses attributed to complete oxidation of the cellulose to oxalic acid. The chemical equation for the formation of the trinitrate is:ģ HNO 3 + C 6H 7(OH) 3O 2 H 2SO 4 → C 6H 7(ONO 2) 3O 2 + 3 H 2O Most lacquers are prepared from the dinitrate whereas explosives are mainly the trinitrate. The overarching consequence is that the nitrocellulose is soluble in organic solvents such as acetone and esters. With fewer OH groups than the parent cellulose, nitrocelluloses do not aggregate by hydrogen bonding. Thus, nitrocellulose can denote mononitrocellulose, dinitrocellulose, and trinitrocellulose, or a mixture thereof. The glucose repeat unit (anhydroglucose) within the cellulose chain has three OH groups, each of which can form a nitrate ester. In precise chemical terms, nitrocellulose is not a nitro compound, but a nitrate ester. Hemicellulose, lignin, pentosans, and mineral salts give inferior nitrocelluloses. The quality of the cellulose is important. The process uses a mixture of nitric acid and sulfuric acid to convert cellulose into nitrocellulose. 3.2 Nitrocellulose decomposition and new "safety" stocks.
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