Oxidation mechanism of perfluorooctanoic acid-functionalized aluminum metastable intermolecular composites regulated by Preignition reactions interface fuel-oxidizer ratio

Abstract

PFOA-functionalized Al Metastable Intermolecular Composites (MICs) refer to the system using aluminum nanoparticles as fuel and PFOA as oxidant. Aluminum is the most widely used metal fuel in energetic materials. Al NPs are widely used because they are relatively cheap, easily accessible, nontoxic, excellent in thermodynamic performance. Fluorine has higher density and stronger oxidation capacity than oxygen element. PFOA has a high fluorine content (68.8%). PFOA-functionalized Al MICs mixed the high calorific value of aluminum and oxidizing fluorine in nano-sized. In this paper, PFOA-functionalized Al MICs with different PIR interface fuel-oxidizer ratios were prepared by electrostatic spray. The microstructure of the MICs was characterized by TEM. PFOA is uniformly coated on the Al NPs. The composition of MIC system was analyzed by FTIR and XRD. The combustion performance of MICs was tested by laser ignition, and the decomposition mechanism of PFOA-functionalized Al MICs was studied by DSC-TG. Results show that the exothermic process and activation energy of MICs are affected by the Preignition reactions (PIR) interface fuel-oxidizer ratios. The ignition and combustion processes of MICs and pressurization rate increase with the increase of oxidizer, and the burning rate decreases with the increase of oxidizer.

Keywords

• Surface functionalization
• PIR interface
• Fuel-oxidizer ratio
• Combustion behavior