Enhance thermal response behavior of energetic composite by doping fluorinated graphene

Fluorinated graphene (FGO) is a two-dimensional layered compound with thermal conductivity and hydrophobicity. Different percentage of FGO (1.00 wt.%, 3.00 wt.%, 5.00 wt.%) was added to the composite energetic system boron/potassium nitrate (B/KNO₃). Through elemental analysis (EA), Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS), the results show that with the increase of fluorination degree, the stretching vibration peak of C-F bond was more obvious, and the contents of fluorocarbon functional groups, especially C-F₂ rise. The results of synchronous thermal analysis and mass spectrometry (DSC-TG-MS) showed that the initial decomposition temperature of fluorinated graphene was around 400 ℃, the enthalpy value was about 7279 J g⁻¹, and a large number of fluorine-containing gas products arising therefrom. The effect of fluorinated graphene on the thermal decomposition performance of energetic system was analyzed by DSC-MS. The results show that fluorinated graphene delayed initial exothermic peak temperature of B/KNO₃ system, and promoted subsequent exothermic reaction. The service performances of B/KNO₃ composites were compared with or without FGO. While adding fluorinated graphene, the moisture resistance and thermal conductivity of the B/KNO₃ composites was improved, flame sensitivity was reduced, thermal safety was improved, gaseous products and combustion heat were increased, flame duration was prolonged, and the ignition delay period was shortened. It is implied that the present of FGO made the composite energetic materials safer under lower heat and more reliable under high heat. FGO plays a role of intelligent regulation and smart responds to different thermal stimuli.