Hydrogen bond networks enhance the safety of energetic salts azobistetrazole-1,1′-dioxy dimethylbiguanide

Abstract

Weak interaction is an important force widely existing in material molecules, which may affect the structure and even properties of materials, mainly including π stacking, hydrogen bond network and van der Waals force, etc. The π-stacking and hydrogen bonding networks in energetic materials have a particularly significant impact on their safety. 1,1′-dihydroxy-azobistetrazole (H2AzTO) with abundant hydrogen bond acceptor and dimethyl biguanide (DMG) with abundant hydrogen bond donor was selected as starting materials, then a new energetic salt with strong hydrogen bond network structure, azobistetrazole-1,1′-dioxy-dimethyl biguanide (DMGAzTO), was synthesized through an acid-base neutralization reaction. The structure of DMGAzTO was characterized by FT-IR, 1H NMR, 13C NMR, EA, and SC-XRD, and the thermal stability and non-isothermal thermal decomposition reaction kinetics of DMGAzTO were studied by DSC and TGA methods. The HOF, detonation velocity, and pressure (D, P) were calculated by Born-Haber cycle and K-J empirical formula. The friction and impact sensitivity (FS and IS) of the compound were examined using a BAM sensitivity tester. Results show that the DMGAzTO salt belongs to the 1:1 type with a molecule of bound water; the peak temperature of thermal decomposition is 502 K; the thermal weight loss rate is 82%; the theoretically calculated D and P are 8217 m s−1 and 27.1 GPa, and the FS and IS are 30 J and 360 N, respectively.