Measurement of moisture outgassing of the plastic-bonded TATB explosive LX-17

Moisture outgassing during isothermal heating of LX-17, a plastic-bonded explosive consisting of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB), was monitored. A moisture outgassing measurement system was constructed to directly monitor the water vapor released from the heated material in real time using an aluminum oxide probe mounted in the stainless steel sample chamber. The total pressure in the sample chamber was also monitored. After an initial high vacuum pump down at room temperature and nitrogen backfill, solid samples were heated and monitored for 2 weeks at 65 °C. Moisture outgassing occurred mainly in the first 10–20 h, reaching approximately 50–70 ppm (parts water per million parts LX-17). The total pressure exceeded the water vapor partial pressure, indicating that outgassing of other species occurred. Good agreement (within an order of magnitude) with previous moisture outgassing studies on TATB-based materials was demonstrated. In addition, the data appeared to validate use of a recently developed kinetic model for predicting moisture outgassing rates of solid TATB formulations.