Other uses Ĭollodion, a solution of nitrocellulose, is used today in topical skin applications, such as liquid skin and in the application of salicylic acid, the active ingredient in Compound W wart remover. ![]() ![]() Nail polish is made from nitrocellulose lacquer, as it is inexpensive, dries quickly, and is not damaging to skin. In 2014, the Philae comet lander failed to deploy its harpoons because its 0.3 grams of nitrocellulose propulsion charges failed to fire during the landing. However, after several missions and flights, it proved not to have the desired explosive properties in a near vacuum environment. For space flight, nitrocellulose was used by Copenhagen Suborbitals on several missions as a means of jettisoning components of the rocket/space capsule and deploying recovery systems. Relative to coatings applications, the nitrate content is higher for propellant applications typically. It is normally the first coat applied, sanded and followed by other coatings that bond to it. Guncotton, dissolved at about 25% in acetone, forms a lacquer used in preliminary stages of wood finishing to develop a hard finish with a deep lustre. Nitrocellulose lacquers have been used as a finish on furniture and musical instruments, both as a clear finish over wood-stained guitars and as In terms of lacquers and coatings, nitrocellulose dissolves readily in organic solvents, which upon evaporation leave a colorless, transparent, flexible film. The principal uses of cellulose nitrate is for the production of lacquers and coatings, explosives, 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 isģ 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 e.g., ethyl acetate, methyl acetate, ethyl carbonate. 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. In the form of collodion it was also a critical component in an early photographic emulsion, the use of which revolutionized photography in the 1860s. It was also used to replace gunpowder as a low-order explosive in mining and other applications. One of its first major uses was as guncotton, a replacement for gunpowder as propellant in firearms. The use of these billiard balls was stopped after they were discovered to be highly flammable and, in some circumstances, explosive.Nitrocellulose (also known as cellulose nitrate, flash paper, flash cotton, guncotton, pyroxylin and flash string, depending on form) is a highly flammable compound formed by nitrating cellulose through exposure to a mixture of nitric acid and sulfuric acid. Nitrocellulose was used as a coating for billiard balls when ivory became scarce in the 1920s. The ever-present hazard of combustion led to the replacement of this film in 1933. In 1889, Eastman Kodak used nitrocellulose to formulate a flexible film base. British chemists refined nitrocellulose synthesis to reduce its sensitivity during handling. Yet, it was highly sensitive and hard to handle. It was more powerful than gunpowder as a propellant. The nitrocellulose produced in this way could be used as a blasting agent. This was the predominant method of nitrocellulose synthesis. ![]() The cotton was rinsed in water to stop the reaction and dried slowly at 100oC (212oF) to prevent ignition. Sulfuric acid was added to prevent the water formed from diluting the nitric acid. Nitric acid (2HNO3) converts cellulose (C6H10O5) into cellulose nitrate (C6H8(NO2)2O5) and water. ![]() Shönbein refined the process to soaking cotton in a mixture of nitric and sulfuric acids. When dry, the apron flashed and exploded. He used a cotton apron to clean up the spill. He accidentally spilled concentrated nitric acid on a table. In 1846, a German-Swiss chemist, Christian Shönbein, discovered an easier method of synthesizing nitrocellulose. The nitrocellulose was an unstable, lightweight, combustible explosive. He formulated the compound by combining nitric acid with wood fibers or starch. Nitrocellulose was discovered by French chemist Henri Braconnot in 1832.
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