The combustion-supporting mechanism of fluoropolymers on aluminum particles studied using reactive dynamics simulations

Abstract

In order to clarify the combustion-supporting mechanism of fluoropolymers, this work focuses on the atomic details of the oxidation of Al nanoparticles with the fluoropolymers and O₂, using reactive dynamics simulations. The results show that the combustion properties of Al–fluoropolymer composites are positively correlated with the fluorine content contained in the fluoropolymers. This is because more Al–O and Al–F bonds are formed, resulting in greater energy release, and the fluoropolymer is efficient in preventing the sintering of aluminum powder during combustion. In addition, the erosion of the alumina layer during the ignition phase results in a considerable boost in the combustion performance of the aluminum particles. Surprisingly, a micro-explosion behavior is found in Al–fluoropolymer composites during combustion, which leads to a much higher oxidation rate of aluminum powder. Our results emphasize the erosion of the alumina layer by F atoms, which provides insights into the atomic-scale reaction mechanism between Al and the fluoropolymers.