THERMAL-BEHAVIOR OF AMMONIUM POLYPHOSPHATE INORGANIC COMPOUND MIXTURES .1. TALC

The chemical interaction between ammonium polyphosphate (APP) and talc was studied under dynamic or isothermal heating conditions. The produ cts of interaction were identified by X-ray methods or separated by th in layer chromatography and analysed. It was shown that APP decomposes above 280-degrees-C and starts to interact with talc above 300-degree s-C, giving binary ammonium silicon tetrapolyphosphate and ammonium ma gnesium polyphosphate or cyclophosphate depending on the initial APP/t alc ratio in the mixture. The formation of magnesium cyclotetraphospha te, magnesium ultraphosphate, silicon oxymonophosphate and silicon dip hosphate is observed after further heating at 400-800-degrees-C. A gla ss of magnesium silicon phosphate is formed at 1000-degrees-C. The sch emes of chemical reactions occurring at different temperatures are pro posed for various APP/talc ratios.