Effect of DGTN Content on Mechanical and Thermal Properties of Modified Single-based Gun Propellant Containing NQ and RDX

In order to improve the mechanical properties of nitroguanidine (NQ) base modified single-base gun propellant, five kinds of propellants with different contents (0 %, 1 %, 2 %, 3 %) were prepared to study the effect of diglycerol tetranitrate (DGTN) content on the mechanical properties and thermal behaviors of the gun propellant. The impact strength and compress strength were tested by simple beam impact testing machine and universal materials testing machine, respectively. The thermal stability and thermal characteristic were tested by vacuum stability test (VST) and differential scanning calorimetry (DSC). Experimental data on comparative study indicates that the mechanical properties of gun propellant can be improved for addition of DGTN. The gun propellant has a better comprehensive mechanical property containing 2 % DGTN. Compared with the blank sample, the impact strength and compression ratio of the propellant increased by 11.36 % and 28 % respectively, and the compression strength decreased by 1.9 %. The vacuum stability results determined that the thermal stability of the five propellants is evaluated to be eligible and increases with the increase of DGTN content. The enthalpy of activation and free energy of activation of propellant increased for the addition of DGTN, the entropy of activation and enthalpy of activation decreased with the increase of DGTN content.