Propellants properties

R. Matyas, M. Kunzel, A. Ruzicka, P. Knotek, O. Vodochodsky, Characterization of Erythritol Tetranitrate Physical Properties, Propellants Explos. Pyrotech. 2015, 40, 185-188. 

Shinde, P.D., Mehilal, R.B.S., Agrawal, J.P. Some transition metal salts of 4,6-dinitrobenzofuroxan Synthesis, characterization and evaluation of their properties. Propellants Explosives Pyrotechnics 28, 77-82 (2003)... 

Aerosol technology may be defined as involving the development, preparation, manufacture, and testing of products that depend on the power of a hquefied or compressed gas to expel the contents from a container. This definition can be extended to iaclude the physical, chemical, and toxicological properties of both the finished aerosol system and the propellants. 

Table 2. Physical Properties of Chlorofluorocarbon and Hydrocarbon Propellants...

Hjdrofluorocarbons andHjdrochloroJluorocarhons. The properties of HFC and HCFC propellants are given in Table 3. Propellant 22 is nonflammable and can be mixed to form nonflammable blends. Some of these propellants are scheduled for phase-out by 2015—2030. 

A comparison of the characteristics associated with propellant burning, explosive detonation, and the performance of conventional fuels (see Coal Gas, NATURAL Petroleum) is shown ia Table 1. The most notable difference is the rate at which energy is evolved. The energy Hberated by explosives and propellants depends on the thermochemical properties of the reactants. As a rough rule of thumb, these materials yield about 1000 cm of gas and 4.2 kj (1000 cal) of heat per gram of material. 

Triethylene glycol dinitrate (TEGDN) is an explosive plasticizer of low sensitivity that has been used in some nitroceUulose-base propellant compositions, often in combination with metriol trinitrate. Butanetriol trinitrate has been used occasionally as an explosive plasticizer coolant in propellants. Its physical properties are Hsted in Table 7. 

Trimethylolethane trinitrate (metriol trinitrate) is not satisfactory as a plasticizer for nitrocellulose, and must be used with other plasticizers such as metriol triacetate. Mixtures with nitroglycerin tend to improve the mechanical properties of double-base cast propellants at high and low temperatures. Metriol trinitrate has also been used in combination with triethylene glycol dinitrate as a plasticizer for nitrocellulose. Its physical properties are Hsted in Table 7 (118-122). 

J. M. Pakulak and C. M. Anderson, Naval Weapons Center Standard Methods for Determining Thermal Properties of Propellants andExplosives, NWC TP 6118, Naval Weapons Center, China Lake, Calif., Mar. 1980. 

Rocket Propellants. SoHd rocket propellants are mostly based on chemically cross-linked polymeric elastomers to provide the mechanical properties required in launchings and the environmental conditions experienced in storage, shipment, and handling (see Elastomers, synthetic). Double-and triple-based nitrocellulose propellants are also employed as rocket propellants. 

Oxidizers. The characteristics of the oxidizer affect the baUistic and mechanical properties of a composite propellant as well as the processibihty. Oxidizers are selected to provide the best combination of available oxygen, high density, low heat of formation, and maximum gas volume in reaction with binders. Increases in oxidizer content increase the density, the adiabatic flame temperature, and the specific impulse of a propellant up to a maximum. The most commonly used inorganic oxidizer in both composite and nitroceUulose-based rocket propellant is ammonium perchlorate. The primary combustion products of an ammonium perchlorate propellant and a polymeric binder containing C, H, and O are CO2, H2, O2, and HCl. Ammonium nitrate has been used in slow burning propellants, and where a smokeless exhaust is requited. Nitramines such as RDX and HMX have also been used where maximum energy is essential. 

Solventless Extrusion Process. The solvendess process for making double-base propellants has been used ia the United States primarily for the manufacture of rocket propellant grains having web thickness from ca 1.35 to 15 cm and for thin-sheet mortar (M8) propellant. The process offers such advantages as minimal dimensional changes after extmsion, the elimination of the drying process, and better long-term baUistic uniformity because there is no loss of volatile solvent. The composition and properties of typical double-base solvent extmded rocket and mortar propellant are Hsted ia Table... 

Table 8. Composition and Properties of Double-Base Solventless Propellant...

Table 9. Composition and Properties of Ball Powder Propellants...

D. R. Cmise, Theoretical Computation of Equilibrium Composition, Thermal Dynamic Properties, and Peformance Characteristics of Propellants Systems, NWC... 

Properties and Surveillance of Solid Propellants CPIA Publication PP-13/SPSP-8, CPIA, Johns Hopkins University, Laurel, Md., 1960, p. 345. 

L. Asaoka, Phase Stabili d Ammonium Nitrate Effects on Minimum Signature Propellant Properties, Vol. 5, 3 CPIA Pubhcation 550, Anaheim, Calif., 1990. 

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