Red Phosphorus for Use in Screening Smoke Compositions

摘要

It has been known for many years that red phosphorus reacts with moist air to produce phosphorus oxyacids and phosphine. The detailed mechanism remains unknown. This problem is of great concern to MoD and to pyrotechnics manufacturers because of the present and likely future importance of red phosphorus as the major constituent of compositions for visual and infrared screening, and because of the concern about the toxicity of phosphine and the possible consequent degradation of the performance of stores containing red phosphorus. Because red phosphorus is used extensively in the plastics industry much work has been published in the patents literature on ways of reducing the rate of evolution of phosphine. The scientific basis for the various claims is not well understood. This report comments on the pyrotechnic problems of using red phosphorus, and surveys the literature (largely patents) to accumulate the wide range of materials which have been claimed to be affective as phosphine and acidity suppressers. Recommendations are made for future research work to clarify the reaction mechanisms. for collaboration between red phosphorus and pyrotechnics manufacturers work to improve the ingredients supply and processing of red phosphorus pyrotechnic compositions for the development of non-destructive test methods for the stability of powdered and compacted composition, and for the quantification of toxic and environmental hazards arising from the use of red phosphorus.