Interaction of nitrocellulose with pentaacyloxyphenyl fullerene derivatives: autocatalytic inhibition in thermal decomposition of nitrocellulose

The safe storage of nitrocellulose has become challenging due to their requirements of extreme storage environments, and existing stabilizers cannot fully meet the demand. Thus, developing new high-performance stabilizers to improve the stability of nitrocellulose is urgently needed. Considering the stabilizing mechanism of stabilizers and the excellent free radical scavenging ability of fullerenes, two novel fullerene-based stabilizers, pentaacyloxyphenyl fullerene derivatives (PAOP-C-60), were designed and synthesized, and their structures were characterized by FTIR, UV-Vis and NMR. The thermal action of PAOP-C-60 during thermal decomposition process of nitrocellulose was studied by thermal analysis, which indicating that the thermal stability of nitrocellulose was increased with addition of PAOP-C-60 and the PAOP-C-60 was found to exhibit superior thermal stability than traditional stabilizer. The results of electron spin resonance showed that fullerene-based stabilizers had a significant scavenging effect on nitrogen oxide radicals, and the IC50 of PAOP-C-60 (0.674-0.818 g L-1) was smaller than that of diphenylamine (1.717 g L-1). Moreover, the intermediate product produced by PAOP-C-60 and nitrocellulose action was extracted and characterized by FTIR. A possible stabilization mechanism of PAOP-C-60, which was different from traditional stabilization mechanism, was proposed.