Probing on Mutual Interaction Mechanisms of the Ingredients of Al/CuO/PVDF Nanocomposites

In this paper, several binary and ternary metastable intermixed nanocomposites Al/CuO, Al/PVDF, CuO/PVDF, and Al/CuO/PVDF have been prepared by simple mechanical mixing and ball milling followed by spray drying methods. In this way, the interfacial structure could be well tuned and compared in terms of reactivity. The nonisothermal DSC curves results showed that the exothermic reaction of Al/CuO/PVDF could be divided into three steps. In addition, it has been shown that for the same formulation, the reaction efficiency, pressurization capacity, and thermal reactivity are greatly dependent on the interfacial structure. As a typical example, composite Al@PVDF/CuO, where Al is fully covered with PVDF, exhibited a higher energy release of 10.7 kJ·cm^-3 and pressurization rates of 22.79 MPa·s^-1·g^-1. The reaction between Al and PVDF has been facilitated in both extent of reaction and efficiency due to their intimate contact. Based on the thermal analysis, condensed combustion product analysis, and gaseous phase identification, the mutual reaction mechanisms of Al/CuO/PVDF have been proposed. The most likely reactions that occurred at each stage of the reaction are summarized, providing insight into the complicated underlying mechanisms. It shows that the regulation of energy release rates and improved efficiency could be easily realized by predesigned interfacial structures.