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In order to improve its water resistance and compatibility with polymer matrix, ammonium polyphosphate (APP) is modified with melamine‐trimesic acid (MEL‐TA) aggregates by supramolecular self‐assembly technology. Chemical structure and morphology of APP@MEL‐TA are investigated by Fourier transform infrared spectroscopy and scanning electron microscopy (SEM), respectively. Intumescent flame retardant system of APP@MEL‐TA and charring‐foaming agent is introduced into polypropylene (PP) matrix. The flammability and combustion behavior of PP composites are investigated by limiting oxygen index (LOI), UL‐94 vertical burning, and cone calorimetry tests. In terms of LOI values and cone combustion results, APP@MEL‐TA performs better than pristine APP. Char residue of PP composites is investigated by SEM and Raman spectra. Flame retardant mechanisms are proposed based on thermal decomposition, combustion results, and analysis on char residue. [ABSTRACT FROM AUTHOR]

Lysine sulfate (LS) powder is at high risk of fire and explosion during its production, processing and storage. Considering its edible and nutritive values, the selection for its explosion inhibitor requires both excellent inhibition performance and environmental friendliness. The inhibition performance of a natural food additive of sodium phytate (SP) on LS dust deflagration is investigated by comparing it with ammonium polyphosphate (APP), which is a widely used flame retardant. The deflagration characteristics of LS mixtures with various mass fractions of SP and APP are recorded by high-speed photography and fine thermocouples. The combustion heat is tested by micro-scale combustion calorimetry. Thermal stability of samples are studied by using a synchronous thermal analyzer. The results show that the deflagration of LS dust is completely suppressed when the mass fractions of APP and SP increase to 2% and 8%, respectively. The corresponding inhibition mechanisms are proposed based on the dust deflagration macroscopic results and microcosmic analysis on thermal decomposition products and residuals. These findings may provide a solution to reduce the probability and damage of dust explosions. [ABSTRACT FROM AUTHOR]