Nitramines continued

Following the above initial period, the remaining UDMH suddenly dropped to concentrations below the FT-IR detection limit, formation of the unknown product(s) stopped, while formation of the nitrosamine continued and formation of the nitramine began. The rate of NO consumption also increased, although not as much as that of UDMH. 

The curves are uniform and contain no discontinuities. As the alcohol content increases, the sensitivity ratio may grow smaller or larger continually as in the case of phenolphthalein, or it may approach a maximum or minimum constant value at a certain alcohol concentration. Nitramine, thymol blue (in acid or alkaline solution), and curcumin behave in the latter fashion. 

A 500 ml round bottom flask equipped with thermometer and overhead stirrer containing 150 ml of nitric acid (98 %) was cooled to 10 °C to which propane diurea 10 g (0.064 mol) was added slowly in small portions under constant stirring and cooling below 18 °C. The reaction mixtiue was stirred at this temperature for 5 min and then 75 ml of acetic anhydride (97 %) was added dropwise at 21 °C to 23 °C. Under this condition the stirring was continued for 8—9 h and finally filtered to yield a white compound which was washed thoroughly and dried. The reaction was monitored by IR spectrum in KBr matrix till the disappearance of the NH peak at 3258 cm. The yield of the fully converted nitramine product was 17.6g (82%). Recrystallization from nitro-methane gave a compound of m.p. > 220 °C (deflagration). With this optimized conditions the batch size was enhanced to 10—15g. The compound was fully characterized by IR, H-NMR and elemental analysis. DTA results showed the decomposition peak temperature at 235 °C. 

One of the most important classes of energetic materials is that containing the nitramine function group. We have made an extensive study of nitramines and the work is continuing. For a secondary nitramine, the six... 

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