To enhance the energy release of Al powder in solid propellant, ploy (difluoroaminomethyl-3-methylethoxybutane) (PDF), which has difluoroamino (NF2), was utilized to improve energy and promote combustion efficiency. In this study, Al with three distinct powder sizes (29 μm, 13 μm, and 1~3 μm) was coated with PDF using the solvent/non-solvent method, leading to the formation of Al/PDF composites. The morphology and characteristics of Al/PDF were then characterized. The results demonstrated that all powder sizes of Al/PDF had core-shell structures, and NF2 of the PDF layer on the Al surface maintained the original structure. The TG curves indicated the amount of the PDF layer related to the powder sizes. Furthermore, Al/PDF exhibited greater hydrophobicity. NF2 prompted Al/PDF, with better catalysis on ammonium perchlorate (AP) decomposition. Compared to Al powder, the ignition delay of Al/PDF was significantly shortened. For mixed samples of Al/PDF and AP, NF2 shorted the ignition delay, improving combustion stability, extending the combustion duration, and forming volatile fluorine compounds. These findings underscore the effects of NF2 in Al/PDF composites, which enhances the energy release of Al and holds promising potential applications.
Keywords: Al powder; NF2; PDF; coating; composites; energy release.