Experimental study and simulation of the reaction mechanism of Al–PTFE mechanically activated energetic composites

Abstract

In order to explore the mechanism of reaction involving Al-polytetrafluoroethylene (PTFE) mechanically activated energetic composites, a molecular dynamics simulation was carried out to predict the pyrolysis of PTFE. Then, density functional theory (DFT) was applied to calculate the mechanism of reaction between the products of PTFE pyrolysis and Al. Furthermore, the pressure and temperature obtained during the reaction of Al–PTFE were tested to study the chemical structure before and after heating. Finally, the laser-induced breakdown spectroscopy experiment was performed. According to the experimental results, the main pyrolysis products of PTFE include F, CF, CF₂, CF₃ and C. The path of the CF₃ + Al → CF₂ + AlF reaction is the easiest to achieve. AlF₃, Al and Al₂O₃ are the main components of the pyrolysis products of PTFE with Al. Compared with Al–PTFE, the ignition temperature required by the Al–PTFE mechanically activated energetic composite is lower and its combustion reaction is faster.