Iodine-Rich Biocidal Reactive Materials

Abstract

ABSTRACTThe objectives of this work are to prepare and characterize iodine-rich thermites and reactive materials for potential application in bio-agent defeat. Iodine-rich compositions were prepared using metal iodate oxidizers in combination with aluminum fuel. Higher iodine contents were achieved using iodine-rich additives, tetraiodoethylene and tin tetraiodide. Reactivity during rapid combustion was evaluated for both nanoscale and micron-scale materials. The nanoscale materials were evaluated directly using a spark-initiated pan dent test. The micron-scale materials were mixed with 50% of nano Al/MoO3 and also evaluated with the pan dent test. The results for the mixed material were shown to fit well to a linear combination of the expected dent for each component, based on a rapid reaction. Results of the pan dent test were used to down-select micron thermites for further testing. Bismuth iodate was synthesized by precipitation from nitric acid solutions. The average particle size was controlled by the addition rate, and sizes included 95 nm (amorphous structure), and 330 nm and 3 micron (both crystalline). Additional sizes were produced by ball milling the 3 micron material, giving 1 micron and 350 nm sizes. Fluoropolymers were included in some compositions to provide additional biocidal products, namely HF, that could be produced from reaction of AlF3 product with water.