Effects of Nano PbZrO 3 on the Decompositions of AP, RDX, HMX and the Combustion of (NG/NC) Propellant

Nanoscale lead zirconate (PbZrO 3 ) was prepared by using co-precipitation method, and characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM). The catalytic performances of PbZrO 3 on the decomposition of ammonium perchlorate (AP), cyclotrimethylene trinitramine (RDX) and cyclotetramethylene tetranitramine (HMX) were examined by differential scanning calorimetry (DSC). The thermal behaviors, nonisothermal decomposition kinetics of nitroglycerin/nitrocotton (NG/NC) double-base propellant with nano PbZrO 3 (PbZrO 3 -DB) were also studied. The results show that PbZrO 3 presents a typical perovskite structure. Nano PbZrO 3 can remarkably reduce the thermal decomposition temperature and apparent activation energy of decomposition process(reduced by 21, 7.4 and 15 kJ/mol respectively). The thermal decomposition of PbZrO 3 -DB propellant is heterogeneous. Thermal decomposition mechanism of PbZrO 3 -DB propellant is a contracting cylinder with phase boundary reaction, and the kinetic equation is: $ \frac{{{\rm{d}}\alpha }}{{{\rm{d}}t}} = \frac{{{{10}^{16.7}}}}{\beta }2{\left( {1-\alpha } \right)^{1/2}}\exp \left( {-1.696 \times {{10}^5}/RT} \right)$ .Used as a combustion catalyst of NG/NC solid propellant, nano PbZrO 3 can obviously increase the burning rate and decrease the pressure exponent (0.37-0.39) in the pressure range of 2-14 MPa. The catalytic combustion action of nano PbZrO 3 is much better than that of PbO.