Single-based propellants

Propellant Single based with DPA, EC, a phthalate plasticizer, camphor Unburned Si, Pb at major level, Ca, Cu, S at minor level, Ba, Fe, K at trace level... 

See Propellants, Single-Base Powders, Double-Base Powders, I. M. R. Powder, Sporting Powder, Nitrocellulose, Pyrocotton, Guncotton, Ball Powder, P1,12 27. See also... 

Single-base propellants. Single-base propellants are essentially formed from pure nitrocellulose that is produced from a cellulose monomer, 25. Cellulose is produced industrially from cotton and wood pulp. The hydroxyl groups ( OH) in the cellulose are nitrated by a... 

Pure nitroglycerin is a stable Hquid at temperate conditions. It decomposes above 60°C to form nitric oxides which in turn catalyze further decomposition. Moisture increases the rate of decomposition under these conditions. Double- and multibase propellants containing nitroglycerin have substantially shorter stabiHty Hves at 65 and 80°C than do single-base propellants. The decomposition of nitroglycerin proceeds as... 

Single-base propellants are mixed in a similar fashion by adding the ingredients to the nitrocellulose in the mixer together with the required amounts of ether and alcohol. The mixing time is about one-half hour, and the temperature is kept below 25°C. The pardy colloidal mixture looks like moist cmde sugar. A maceration step may be included to increase homogeneity. 

Continuous Solvent—Extrusion Process. A schematic for a typical continuous process, widely used for making solvent propellant for cannons, is shown in Figure 7. This continuous process produces ca 1100 metric tons of single-base propellant per month at the U.S. Army Ammunition Plant (Radford, Virginia). Continuous processes have also been developed for double- and triple-base propellants and for stick as well as granular geometries. A principal aspect of these processes has been the extensive use of single- and double-screw extmders instead of the presses used in the batch process. 

Fig. 7. Continuous process for solvent-extmded single-base propellant (automated single-base line). Vey = conveyor.

E. R. Bixon and D. Robertson, "Lifetime Predictions for Single Base PropeUant Based on the Arrhenius Equation," in Fifth International Gun Propellant and Propulsion Symposium, ARDEC, Dover, N.J., Nov. 1991. 

Current propellent explosives may be divided into three classes single base, double base and composite however double base propellants which contain picrite are often considered a separate class and called triple base. 

Single base propellants are basically nitrocellulose which has been made colloidal by the action of solvent. 

Single base propellant. Propellant based on nitrocellulose without the inclusion of nitroglycerine. 

Single-base propellants, 10 725 Single-carbon insertion reactions in organoboranes, 13 654—657 Single-cell drum filters, 11 357 Single-cell protein(s) (SCP), 13 688,16 315, 26 474... 

Single-base propellants are made from NC that is gelatinized with the solvents ethanol or diethyl ether. A small amount of diphenylamine, (C6H )2NH, is also... 

Table 4.8 Physicochemical properties of a single-base propellant.

Though the theoretical of black powder is less than that of single-base, doublebase, and AP-based composite propellants, black powder is useful for short-duration operation of simple propulsive systems. The advantages of the use of black powder are its low cost, its minimal deterioration with age, and simple regulation of the propulsive force by adjustment of the quantities used. 

This criterion is the so-called T combustion instability. The stability criterion expressed by < 1 is not sufficient to obtain stable combustion when the flame temperature is dependent on pressure.lO In general, m is approximately zero in the high-pressure region for most propellants. However, l/of nitropolymer propellants such as single-base and double-base propellants decreases with decreasing pressure below about 5 MPa. Since direct determination of m is difficult, the heat of explosion, is evaluated as a function of... 

Of these, the most successful appeared in 1887 when Alfred Nobel patented a nitrocellulose propellant plasticised with nitroglycerine. Known as a double-base propellant, it is virtually smokeless, with a very high specific impulse as compared to gunpowder. Single-base propellants were developed in 1865 and 1890 by Schultz and Vieille respectively and these took the form of gelatinised nitrocellulose for use in firearms and mortars. 

Single base" smokeless powder, developed mainly in the United States, uses only nitrocellulose. "Double base" smokeless powder, developed in Europe, is a blend of nitrocellulose and nitroglycerine. "Cordite," a British development, consists of 65% NC, 30% NG, and 5% mineral jelly. The mineral jelly (a hydrocarbon material) functions as a coolant and produces substantial amounts of CO 2, CO, and H 2O gas to improve the propellant characteristics. "Triple base" smokeless powder, containing nitroguanidine as a third component with nitroglycerine and nitrocellulose is also manufactured. 

Andreev Belyaev (Ref 1) give the following values fot burning rates of some Russian propellants 0.1 cm/sec at atm pressure to 0.3 at 4kg/cm pressure for a single-base proplnt similar to US "Pyro propint (p 178) for a double-base NG proplnt - 0.3 cm/sec at atm press, 1.9 at 100kg/cm, 3.0 at 200,... 

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