Thermal decomposition of energetic materials. 44. Rapid thermal decomposition of the propyl-1,3-diammonium salts of NO ⁻₃ and ClO ⁻₄ , and the crystal structure of the ClO ⁻₄ salt

Abstract

The temperature dependence of the IR spectra of the condensed phase (dT/dt=5°C min⁻¹) and the fast thermolysis (dT/dt≥100°C sec⁻¹) of propyl-1,3-diammonium dinitrate (PDD) and diperchlorate (PDP) are compared. Rapid-scan FTIR/temperature profiling shows that PDP explodes on heating while PDD decomposes with much less energy. HNO₃(g) is formed by deneutralization in the initial decomposition of PDD, but HClO₄(g) is not detected from PDP. PDP is unique among the compounds studied by this technique in that a solid-solid phase transition can be detected during rapid heating. The initial phase of PDP has been characterized by X-ray crystallography: monoclinic,P2₁/c,a=7.316(2),b=14.428(2),c=9.742(2) Å,β=96.81°,V=1021.1(3) ų,Z=4,D=1.789 g cm⁻³,R(F)=0.034,R(wF)=0.040.