Laser-driven decomposition and combustion of BTTN/GAP

The objective of this work was to study the near-surface phenomena of an energetic binder, butanetriol trinitrate/glycidyl azide polymer, during thermal decomposition and combustion. A triple quadrupole mass spectrometer with microprobe sampling was used to obtain gas-phase quantitative species from CO₂ laser-induced decomposition and laser-assisted combustion of the butanetriol trinitrate/glycidyl azide polymer sample. To get the species profile as a function of height from the surface, a linear positioner was used to move the sample towards the microprobe during sampling. Fine-wire thermocouples were used to get the surface temperature and gas-phase temperature profile in the primary flame zone. The experiments were conducted at a laser heat flux of 35 W/cm² and in both argon environment and ambient air conditions with varying pressures from 1.0 to 4.0 atm. The flame structure and burning event were recorded using a digital camcorder so that the burning rates at these pressures can also be determined.