GUNCOTTON, the final product of the intensive treatment of cotton with a mixture of nitric and sulphuric acids, is a white inodorous, tasteless solid, retaining the structure of the original cotton (see EXPLOSIVES). It is insoluble in water, alcohol, ether and glacial acetic acid, but dissolves in acetone, alkyl acetates and nitrobenzene. When the strongest acids are employed in nitration, the amount of nitrogen present as nitrate in the nitrated cotton approximates to 14.14%. If cellulose, the essential constit uent of the cotton fibre, be regarded as having the simplest empiri cal formula, then guncotton is trinitrocellulose (cellulose trinitrate), With a doubled formula for cellu lose, as C12H20010, guncotton becomes hexanitrocellulose, C12H1404 Vieille, who stated (1882) that nitration of cellulose occurred in eight stages, assumed that cellulose was C24H4002o• Of these nitration products only the undeca- and deca-nitrocellu loses, and C24H30010(0.NO2)10, have the char acteristic property essential to guncotton of being insoluble in a mixture of ether and alcohol. This property distinguishes gun cotton from the less nitrated celluloses which are referred to as collodion cotton or soluble nitrocellulose owing to the fact that they dissolve in the ether—alcohol solvent. Guncotton has superior explosive properties to those of collodion and has been extensively employed in conjunction with nitroglycerine for the production of cordite, the British service explosive. The blending of the two ingredients is brought about by acetone, but by the use of collo dion with a larger proportion of nitroglycerine a cordite is obtain able without the employment of acetone.
Cf. T. E. Thorpe, Dictionary of Applied Chemistry, vol. iii. (1922).