Effect of varied proportion of GAP-ETPE/NC as binder on thermal decomposition behaviors, stability and mechanical properties of nitramine propellants

To improve the thermal performance and mechanical properties of nitramine propellant, varied proportions of GAP-ETPE/NC were applied as binders. The thermal behavior of propellants was investigated by using differential scanning calorimetry (DSC), the thermal stability of the propellants was studied by methyl violet experiment and vacuum stability test, and the mechanical properties were also examined. It was found that the DSC curve of GAP-ETPE shows a single exothermic peak at around 250 °C, and TG-DTG curves of GAP-ETPE exhibit two major steps of mass loss. GAP-ETPE has a good compatibility with nitrocellulose, and there is no interaction between GAP-ETPE and RDX in solid phrase. When increasing the proportion of GAP-ETPE content in the binder system, the decomposition peak of nitrocellulose disappears gradually and the peak temperature of main decomposition increases. Meanwhile, activation energy and frequency factor calculated by Kissinger and FWO methods using non-isothermal thermoanalytical data all increase slightly. And the thermal stability of propellant gets improved greatly when GAP-ETPE is introduced into the binder system. When the proportion of GAP-ETPE/NC is 1:1 and 1:2 in the binder system, the mechanical properties of nitramine propellant are relatively excellent.