Preparation of spherical DAOAF with micro-nano structure by emulsion method: To improve short-pulse initiation performance

Abstract

In order to take into account the advantages of good processing performance of micron 3,3′-diamino-4,4′-azoxyfurazan(DAOAF) and high sensitivity of short-pulse initiation of nano DAOAF, Spherical DAOAF products with nano-microstructure were prepared by oil-in-oil emulsion method. The laser-induced air shock wave detonation performance, mechanical sensitivity and short-pulse initiation sensitivity of raw DAOAF and spherical DAOAF were tested and compared. The results showed that the optimum process conditions of emulsion stability were as follows: using Tween-80 as the surfactant at a concentration of 0.3 g·mL−1, a solvent-non-solvent volume ratio of 1:3, and emulsion standing time less than 10 minutes. Compared to the raw DAOAF, the crystal structure of DAOAF sample prepared by emulsion method did not change, only the morphology changed. The DAOAF sample prepared by emulsion method is spherical, and the surface is self-assembled by nanorod-like DAOAF, the particle size distribution is uniform and the dispersion is good. The thermal decomposition peak temperature of spherical DAOAF did not change significantly, but the activation energy of thermal decomposition decreased by 30.07 kJ·mol−1, the characteristic velocities of the laser-induced micro-explosion shock waves increased 12.4 %, the 50 % short-pulse initiation current of the impactor decreased from 3.8 kA to 2.3 kA, and the mechanical sensitivity of DAOAF showed no significant change before and after spherical transformation.