Nitroglycerin composition

Explosive material with low rate of combustion. May be either solid or liquid. Will burn smoothly at uniform rate after ignition without depending on interaction with atmosphere. Single base propellant consists primarily of matrix of nitrocellulose. Double base propellant contains nitrocellulose and nitroglycerine. Composite propellant contains oxidizing agent in matrix of binder. 

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. 

Many nitrated products are explosives, including DNT, TNT, and nitroglycerine (NG). At least some mononitroaromati.es can also be exploded under certain conditions (20). Because of the high heats of nitration, mnaway reactions followed by severe explosions have occurred in industrial batch nitrators. To rniiiimi2e these potential ha2ards, the compositions of the feed acids and reaction conditions are currently better controlled than formerly. 

A third type of propellant, the composite modified-double-base propellant, represents a combination of the other two types. These propellants are made from mixtures of nitroglycerine and nitrocellulose or similar materials, but with crystalline oxidizers such as ammonium perchlorate also included in the matrix. 

The choice of composition of a semi-gelatine depends ultimately on two requirements, namely the strength required and the resistance to water needed for the particular application. For economic reasons the lowest nitroglycerine content which satisfies both these requirements is always chosen. 

Before nitrates and particularly ammonium nitrate were readily available commercially, explosives were developed based on chlorates and perchlorates. These also are still used in some countries. In general perchlorates are considered less dangerous than chlorates and therefore preferred. They are easily sensitised, so that in addition to explosives of this type based on nitroglycerine, others have been based on various organic liquids, particularly nitrobodies. History shows that chlorates and perchlorates must be regarded as temperamental substances, liable in bulk to lead to inexplicable accidents. Particularly when mixtures of chlorates and oxidising materials are allowed to become wet and then dry out, conditions can arise in which there is an appreciable sensitiveness to friction and impact. Explosives of this type have an unfortunate record of accidents. They are used, therefore, to a limited extent only, now that safer compositions are available. 

M55 rockets pose the greatest storage risk because they contain approximately 20 pounds of M28 propellant, a double-base propellant composed of nitroglycerine, nitrocellulose, plasticizers, a bum-rate modifier, and a stabilizer. The exact composition is given in Table 1-4. The propellant slowly decomposes exother-... 

Analysis of a group of smokeless powders of known composition showed that the main components of their headspace vapor were acetone, toluene and limo-nene the concentration of nitroglycerin (NG) was relatively low. A series of... 

Most composite propellants in wide use today use ammonium perchlorate as the oxidizer component. While such propellants benefit from high specific impulse and a lower vulnerability than double-base propellants based on nitroglycerine, they have a significant environmental impact, the exhaust fumes being rich in corrosive hydrogen chloride leading to acid rain after the launch of missiles/rockets. 

Since the energy contained within double-base propellants is limited because of the limited energies of nitrocellulose (NC) and nitroglycerin (NG), the addition of ammonium perchlorate or energetic nitramine particles such as HMX and RDX increases the combustion temperature and specific impulse. Extensive experimental studies have been carried out on the combustion characteristics of composite-modified double-base (CMDB) propellants containing AP, RDX or HMX parhclesli- l and several models have been proposed to describe the burning rates of these pro-... 

Explosive Compositions, Brisont (of High Density). The following expl compns con eg solid TNT and liquid nitric esters are described. Nitroglycerin 15—20, soluble Nitrocellulose 0—7.5, Kieselguhr 0—5, stabilizer 0-2.5, TNT 85-70%. The TNT is in the form of crushed flakes Ref J. Taylor and S.H. Davidson, BritP 578371 (1946) CA 41, 1842 (1947)... 

The diffusion coefficients of nitroglycerin and triacetin in doublebase propellant have been measured at 77°-140°F. Activation energies for diffusion ranged from 10 to 13 kcal./mole. Thus, cure rates for a given propellant composition can be expected approximately to double in going from 120° to 140°F. 

The choice of material for use as inhibitor depends mainly upon the type of propellant, that is, DB, CMDB, Composite and Fuel-rich and also on the ingredients in their formulations. For double-base propellants, cellulosic materials such a cellulose acetate, ethyl cellulose and different filled or unfilled flexible polyesters are used while fuel or binder material filled with inert substances such as asbestos, mica, silica, etc. in fine powder form is used for composite propellants. Since nitroglycerine is present in CMDB propellants also as in DB propellants, the materials used for DB propellants may also be used with minor modifications for the inhibition of CMDB propellants. 

Smokeless propellants may be taken as another example of composite explosives. These may be either mixtures of nitrocellulose of differing degrees of nitration, partly in a colloidal and partly in a fibrous state with an admixture of the remaining solvent and a stabilizer or a solution of nitrocelluloses in carbamite (centralite) and nitroglycerine with an admixture of components such as aromatic nitro compounds, nitroguanidine, graphite etc. 

In 1929, Stettbacher [90] suggested the use of a mixture of PETN with nitroglycerine, under the name of Penthrinite. Such a mixture may be plastic provided suitable amounts of nitroglycerine and PETN with crystals of a proper size are used and both constituents are thoroughly mixed. Stettbacher recommended a composition ranging with the limits ... 

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