Explosives nitrocellulose

Experiments on burning nitrocellulose (deflagration and explosion) were carried out in World War II by Rideal and A. J. B. Robertson [91]. One interesting observation they made was that nitrocotton heated for a long time at 200°C under a pressure of 50 mm Hg liquefied shortly before the explosion. Nitrocellulose has been known to melt while being stabilized in an autoclave at an elevated temperature, since it overheats if there is too little water in the autoclave (on melting nitrocellulose, see p. 242). 

High explosives Lead acids (explosives) Mercury oxide (explosives) Nitrocellulose powder (explosives)... 

When the nonvolatile liquid explosives are heated, they do not evaporate, but decompose before the temperature reaches the boiling point. The reaction in the liquid takes a very important part such as in nitro compounds, nitra-amine explosives, nitrocellulose gunpowders, nitroglycerine gunpowders, etc. 

In mid-1922, the MICC requested and obtained fi om the IG its final sets of plant survey forms and questionnaires. In some cases it also requested follow-up information, which IG firms also supplied. The information covered explosives (nitrocellulose and nitroglycerine propellants, TNT, picric acid, and a host of other nitrogenous substitute high explosives), as well as the principal chemical warfare agents. 

The chemical industry s interest in polymers dates back to the 19th century. In those days it was a case of synthetically modifying natural polymers with chemical reagents to either improve their properties or produce new materials with desirable characteristics. Notable examples were nitration of cellulose giving the explosive nitrocellulose, production of regenerated cellulose (rayon or artificial silk) via its xanthate derivative, and vulcanization of rubber by heating with sulphur. Manufacture of acetylated cellulose (cellulose acetate or acetate rayon) developed rapidly from 1914 onwards with its use both as a semi-synthetic fibre and as a thermoplastic material for extrusion as a film. 

Nitrocellulose, colloided, granular or flake, wet with not less than 20% water Nitrocellulose, dry. See High explosive Nitrocellulose, wet with not less than 30% alcohol or solvent... 

Nitrocellulose is among the least stable of common explosives. At 125°C it decomposes autocatalyticaHy to CO, CO2, H2O, N2, and NO, primarily as a result of hydrolysis of the ester and intermolecular oxidation of the anhydroglucose rings. At 50°C the rate of decomposition of purified nitrocellulose is about 4.5 x 10 %/h, increasing by a factor of about 3.5 for each 10°C rise in temperature. Many values have been reported for the activation energy, E, and Arrhenius frequency factor, Z, of nitrocellulose. Typical values foiE and Z are 205 kj/mol (49 kcal/mol) and 10.21, respectively. The addition of... 

Military. The single-component explosives most commonly used for military compositions are TNT, RDX or HMX, nitrocellulose, and nitroglycerin. The last two are used almost exclusively to make propellants. The production volume of TNT far exceeds that of any other explosive. It is used as manufactured, as a base of biaary slurries with other high melting explosives, or ia ternary systems generally containing a biaary mix and aluminum. 

The first successhil attempt to make textile fibers from plant cellulose can be traced to George Audemars (1). In 1855 he dissolved the nitrated form of cellulose in ether and alcohol and discovered that fibers were formed as the dope was drawn into the air. These soft strong nitrocellulose fibers could be woven into fabrics but had a serious drawback they were explosive, nitrated cellulose being the basis of gun-cotton (see Cellulose esters, inorganic esters). 

Basic Research Leading to the Development of Ideal Propellants. Explosive Plasticizers for Nitrocellulose , PATR 1616 (1946) 8) V. 

Like nitrocellulose, nitroglycerin also undergoes a slow first-order exothermic decomposition at temperatures below 140°C. As the pressure is increased, this decomposition reaction is followed by a sudden explosive reaction. Evidence suggests that the explosive reaction is autocatalyzed by the accumulation of N02. The combined results of several studies indicate that... 

Uses The largest use is in the manufacture of fertilizers. It is also used to make one of the raw materials for nylon, virtually all gunpowder and explosives (nitroglycerin, nitrocellulose, TNT, ammonium nitrate, etc.) and the starting materials for polyurethane elastomers and paints. 

Although these are no longer used as explosives, they are formed from diphenylamine that is used as a stabilizer for nitrocellulose explosives. The metabolism of nitrodiphenylamines has been examined under anaerobic conditions, and phenazine and 4-aminoacridine that are cyclization products of the initially formed 2-aminodiphenylamine have been identified (Drzyzga et al. 1996). 

The first high explosive discovered was probably nitrocellulose, in the period 1833 to 1846, but its development was long delayed by difficulties in obtaining a stable product. The two major discoveries in this field were of nitroglycerine by Sobrero in 1847 and TNT by Wilbrand in 1863. Of these, the first to attain commercial importance was nitroglycerine. 

Pure PETN is too sensitive to friction and impact for direct application for military purposes. It can usefully be mixed with plasticised nitrocellulose, or with synthetic rubbers to obtain plastic or mouldable explosives. The commonest application, however, is in conjunction with TNT in the form of pentolites. Pentolites are usually obtained by incorporating PETN into molten TNT. A small amount of the PETN goes into solution, but the bulk remains suspended in the liquid and the whole mix can suitably be used in preparing cast charges. Pentolites containing 20-50% PETN are the commonest in practice. 

Nitrocellulose is used in commercial high explosives mainly to thicken... 

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