Identification of propellant charges, in ammunition is of considerable importance in forensic analysis, The charge in small arms ammunition are generally of single base (nitro cellulose with small amounts of additives in the form of stabilisers or small amounts of additives in the form of double base (nitro cellulose with 10-15% of nitroglycerine). In each type there are certain variations in the percentage of major and minor constituents from one manufacturer to the other. Stabilisers such as ethyl centrolite (EC), diphenyl urea or diphenyl amine (DPA) are added to prolong shell life. Other less common stabilizers such as dibutyl phthalate (DBP) and flash inhibitors such as 2, 4 dinitrololune may also be incorporated. Methods based on thermal decomposition provide guidelines for differentiation and identification of propellants. Other methods of importance include particle size distribution and viscosity measurement. The variation in the composition of constituents has also been taken into consideration by chromatographic and spectroscopic methods viz. thin layer chromatography, pyrolysis gas chromatography mass spectrometry and high" performance liquid chromatography. As the physical nature and thermal behaviour of propellants are more or less uniform and the methods based on chemical composition lack precise optimisation and standardization, an attempt to explore the effect of constituents in propellants on the solubilization characteristics of surfactant related to two-phase systems of organic solvent and water has been made.
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