Preparation and properties of an AP/RDX/SiO ₂ nanocomposite energetic material by the sol-gel method

A nanocomposite energetic material was prepared using sol-gel processing. It was incorporated into the nano or submicrometer-sized pores of the gel skeleton with a content up to 95%. AP, RDX, and silica were chosen as the energetic crystal and gel skeleton, respectively. The structure and its properties were characterized by SEM, BET methods, XRD, TG/DSC, and impact sensitivity measurements. The structure of the AP/RDX/SiO ₂ cryogel is of micrometer scale powder with numerous pores of nanometer scale and the mean crystal size of AP and RDX is approx. 200 nm. The specific surface area of the AP/RDX/SiO ₂ cryogel is 36.6 m ²g ^-1. TG/DSC analyses indicate that SiO ₂ cryogel can boost the decomposition of AP and enhance the interaction between AP and RDX. By comparison of the decomposition heats of AP/RDX/SiO ₂ at different mass ratios, the optimal mass ratio was estimated to be 6.5/10/1 with a maximum decomposition heat of 2160.8 Jg ^-1. According to impact sensitivity tests, the sensitivity of the AP/RDX/SiO ₂ cryogel is lower than that of the pure energetic ingredients and their mixture.