Hydrophobic-modified fuel for dual-stress resistance: Al@FAS-17/CuO/PVDF-based nano composite energetic films with superior anti-aging properties

Nano composite energetic films offer easier control over ignition and combustion performance, achieving an optimal balance between high energy output and low sensitivity, making them a research hotspot in metastable intermolecular composites. Among them, overcoming the aging issue during long-term storage of nano-aluminum thermites systems is a critical challenge to be addressed. This study employed electrospinning to prepare nano composite energetic films and anti-aging nano composite energetic films (structure of loaded-fiber), composed of CuO (oxidizer), PVDF (binder), and Al (fuel) surface-modified with a hydrophobic layer of 1 H ,1 H ,2 H ,2 H -perfluorodecyltrimethoxysilane (6.9±2 nm). Accelerated aging tests under dual stress conditions of thermal and humidity were conducted. Compared with nano-Al, the aging mechanism of the nano composite energetic films was divided into two processes: physical effects (agglomeration) and chemical reactions (induction phase, hydrogen release phase, and rapid deactivation phase). The combustion process consisted of two stages: a pre-ignition reaction of Al 2 O 3 , a thermite reaction between Al and PVDF, and a thermite reaction between Al and CuO. The anti-aging nano composite energetic films exhibited only minor declines in burn rate after 48 h of aging and maintained stable self-propagating combustion even after 144 h of accelerated aging, demonstrating excellent storage stability under high-temperature and high-humidity conditions. In contrast, this material not only extends the storage life of nano composite energetic films but also provides a new approach for ignition design in high-humidity environments.