Novel Flame Inhibiting Materials to Increase Red Phosphorus Obscurant Safety

The proposed effort provides several concepts for improving the use of Red Phosphorus (RP) by retarding flame size and temperature as well as reducing incendiary properties of RP pots/devices and phosphine generation in storage without reducing obscuration efficiency. The proposed concepts include burning RP under fuel rich conditions which will include a) high ratios of RP/oxidizer, b) coating RP particles with several candidates of polymeric materials which upon ablation generate CO2 species as well as other flame arresting materials, and c) exclude oxidizer from the solid state mixture and substitute with a highly exothermic mix which will cause RP ablation as P4 (instead of P, and P2 which burns faster than P4) vapor to be converted into oxides and hydrated aerosols at lower temperatures upon mixing with air under “fuel rich� conditions. Finally, a flame inhibiting canister is proposed which is performing by ablating species which will reduce the temperature of the RP gases as they percolate through a porous structure attached on top of the RP device. Several key experiments are proposed in the determination of % obscuration, cloud yield, and mass extinction coefficients in the visible, near, mid and far IR.