Thermal decomposition studies on cured energetic polymer systems (GAP and BAMO-THF)

Azido polymers like Glycidyl Azide Polymer (GAP), Bis Azido Methyl Oxetane (BAMO) and their copolymers with Tetrahydro Furan (THF) are emerging as energetic binders for futuristic propellants and explosive formulations. In the present study, the curing of GAP and BAMO-THF was established using selected curatives and cross-linkers, i.e. MDI-pentaglycerol combination for GAP and TDI-pyrogallol combination for BAMO-THF. Composite propellants were cast with the selected azido polymer systems. DSC and TG techniques were applied to investigate the thermal behavior of the binder systems (polymers + curative + cross linkers) and propellants. It was found that the binder exhibits single stage weight loss suggesting that it decomposes as a unified multicomponent system, whereas the propellant shows a two stage decomposition corresponding to the decomposition of the polymer followed by that of AP. From TG it was inferred that the exothermic decomposition of the polymers in the first stage facilitates the decomposition of AP. These findings are in line with those reported for related systems.