Advances in surface coating and performance enhancement of ammonium perchlorate

Ammonium perchlorate (AP), which has the advantages of high oxygen content, good thermal and chemical stability, and no solid residue after thermal decomposition, is considered to be the most widely used oxidiser for solid propellant applications. However, the high mechanical sensitivity, moisture absorption, and thermal decomposition temperature of AP seriously affect the performance of the solid propellant. In this paper, we systematically review the research progress of the improvement of desensitization, anti-hygroscopicity, and thermal decomposition performance by surface coating of AP. At the same time, the surface coating methods are focusing on electrospray technology, reduced pressure distillation, ultrasonic synthesis, liquid phase deposition, supercritical fluid, intermittent spray coating, and electrostatic self-assembly coating method. Among above, intermittent spray coating and liquid phase deposition method are the preferred surface coating method due to their uniformity of coating, ease of adhesion and good performance enhancement. It is expected that the research on surface coating and performance enhancement of AP can greatly promote the innovation and development of AP in the field of high burning rate solid propellant.