Fluoroelastomer pyrotechnic time delay compositions

The feasibility of aluminium- or magnalium-filled fluoropolymer Viton B as an open-burn time delay was investigated. Film samples with a thickness of 245 ± 21 μm were prepared via a slurry casting process. Fuel filler content was varied from 20 to 60 mass/%. The films retained the elastic properties of the parent polymer except that the elongation at break decreased rapidly with increasing filler content. Sensitivity tests showed that the films were insensitive to ignition by friction and impact. EKVI thermodynamic simulations showed that, for both systems, the maximum energy output is ca. 8.3 MJ kg−1. Energy measurements indicated that the maximum energy output occurred in the range 30–40 mass/%. Maximum burn rates of 82 and 40 mm s−1 were achieved using a magnalium and flake aluminium as fuels, respectively.