The thermal decomposition of basic lead styphnate RD 1349 at its ignition temperature

Basic lead styphnate RD 1349 forms the primary explosive component of several high temperature fuzehead formulations and percussion primers. A study of its thermal decomposition under controlled conditions near its ignition temperature (521-525 K) shows that it decomposes very rapidly, following a second order autocatalytic rate law. The kinetics of this reaction are initially controlled by the ''nucleation of reactive molecules''occurring on the crystal surfaces or glide planes, by the growth of these nuclei as the reaction proceeds and, in the rate determining step, by their subsequent reaction in the bulk of the material. The rate determining step in this reaction follows Arrhenius kinetics with an activation energy of 197 kJ mol-1 and pre-exponential log10 A (s-1) = 17.9.