Preparation And Properties Of GAP-based Nano-composite Energetic Materials

In order to meet the needs of modern weapons,improve the high sensitivity,low energy output and other shortcomings of traditional explosives,and obtain new energetic materials with high energy insensitivity,the preparation of nanocomposite energetic materials has attracted the attention of researchers.In this paper,NC/PETN,NC/GAP/PETN and NC/GAP/CL-20 nanocomposite energetic materials were successfully prepared by sol-gel method with NC and GAP as energetic gel skeletons,and scanning electron microscope?SEM?,infrared spectroscopy?IR?,X-ray diffraction?XRD?,specific surface area?BET?and X-ray photoelectron spectroscopy?XPS?were used to analyze the microstructure of nanocomposites.Its thermal decomposition performance,energy performance and mechanical sensitivity also were characterized.The specific results are as follows:NC/PETN nanocomposite energetic material:the particle size of Nano-PETN were about100 nm,and the PETN particle were encapsulated in the NC gel skeleton to form a nanocomposite.The EDS results show that the surface of the composite has three elements C,N,O.There is obvious characteristic peak of PETN in the IR spectrum.The composite material only shows an exothermic peak at 141.2°C,and the thermogravimetric curve only shows a weight loss stage,corresponding to the thermal decomposition process of the composite material.The energy performance of nanocomposite is improved with the mass percentage of PETN increasing,and this indicates that PETN is a better energy additive for the propellant.NC/GAP/PETN nanocomposite energetic materials:SEM images shows that the NC/GAP gel skeleton has a nanopore structure,and PETN particles are encapsulated in the gel skeleton.The XRD and IR reveals that PETN has no phase change before and after preparation,and the molecular structure of NC,GAP and PETN has not changed.The specific surface area,pore size and pore volume of NC/GAP/PETN are significantly reduced due to the PETN particles filled in the pores of NC/GAP gel.The thermal reactivity of NC/GAP gel is higher than that of PETN.The main gas products of thermal decomposition of nanocomposites were CO₂,N₂O,CO,NO and H₂O,and N₂ that IR does not detect.The energy performance will be higher with the content of NC increasing.The friction sensitivity and impact sensitivity of the nanocomposite decreasing with the content of GAP increasing,and the safety performance is improved.NC/GAP/CL-20 nanocomposite energetic materials:the grain size of nanocomposites is about 74 nm,and the morphology of CL-20 has not changed.The two peaks in the DSC curve corresponding to thermal decomposition of NC/GAP and CL-20,respectively.And the thermal reactivity of NC/GAP gel is higher than CL-20.The main gas products are CO₂,N₂O and H₂O,as well as a small amount of CO,CH₄,NO,and N₂ that IR has not detected.At the end of decomposition,many NH₃ also are produced.The introduction of CL-20 significantly increases the I_sp value of the propellant,so adding the NC/GAP/CL-20 nanocomposite to the propellant will help to improve the energy performance of the propellant.The mechanical sensitivity of NC/GAP/CL-20 is lower than that of the raw material CL-20.It is a non-sensitive composite that can be added to propellants as an energetic additive to improve its combustion performance.