Enhanced combustion performance of core-shell aluminum with poly (vinylidene fluoride) interfacial layer: Constructing the combination bridge of aluminum powder and poly(vinylidene fluoride)

Uniform coating of organofluorides on aluminum powder surfaces has always been a challenging problem. Herein, the polyvinylidene fluoride (PVDF) is uniformly bonded to the surface of the aluminum powder via the bridge formed by the self-assembly reaction of tannic acid (TA) and iron ions, and successfully prepared an dual-core shell structure aluminum composite (Al@TA-Fe@PVDF) coated with PVDF uniformly. Molecular dynamics simulation calculations reveals that the binding energy of PVDF and TA is much higher than that of Al2O3 on the surface of aluminum powder. In addition, the results reveals that PVDF layer of Al@TA-Fe@PVDF is uniformly coated on the surface of aluminum particles. The hydrophobicity brought by the F and C elements in the double interfacial layer TA-Fe@PVDF can improve the water corrosion resistance of aluminum powder. More importantly, the combustion and ignition performance of Al@TA-Fe@PVDF are greatly improved compared with pure aluminum powder. The TA-Fe@PVDF interfacial layer can promote the aluminum powder to be ignited at a temperature lower than the melting point of aluminum in oxygen, changing the typical reaction process of aluminum.