Rigid polyurethane foam composites based on iron tailing: Thermal stability, flame retardancy and fire toxicity

Abstract

In order to explore the potential utilization value of iron tailings, the typical solid waste-iron tailings was introduced into rigid polyurethane foam (RPUF) as a flame retardant filler in this paper. The flame retardant performance, combustion performance, gas-phase products and char residue’s related properties of RPUF/ITS composites were systematically investigated by limiting oxygen index, thermogravimetric (TG), cone calorimetry (CCT) and thermogravimetric-infrared spectrometry (TG-FTIR). The results showed that ITS improved the overall thermal stability of the composites, and the T-5%, T-50%, Tmax1, Tmax2 and char residue rates were all higher than those of the pure samples. The CCT indicated that ITS had a certain effect on smoke suppression and heat release reduction. The peak heat release rate of RPUF-6 was reduced by 22.75% compared with that of the pure sample, and the total smoke release of RPUF-2 was reduced by 25.36%. Smoke factor (SF), fire growth rate index and fire performance index indicated that ITS reduced the fire risk of RPUF/ITS composites. TG-FTIR showed that ITS inhibited the decomposition of RPUF/ITS composites, and the release intensity of hydrocarbons, CO2, isocyanate compound, CO, aromatic compounds and esters decreased significantly. TG, MCC, scanning electron microscope and Raman implied that ITS promoted the formation of a dense char layer in RPUF and improved the heat resistance of the char layer.

Inorganic/organic phosphorus‐based flame retardants synergistic flame retardant rigid polyurethane foam

“…The pyrolysis volatiles of pure RPUF include aromatic components (3028, 1625, and 1513 cm À1 ), aliphatic components (2932 and 2869 cm À1 ), CO 2 (2356 cm À1 ), NCO (2310 cm À1 ), and ester/ether components (1266 and 1113 cm À1 ). [8,37] The incorporation of these fillers reduces the intensity of gas products. Besides, the new peaks at 963 and 929 cm À1 attributed to NH 3 are observed in the FTIR of RUPF with flame retardants.…”

Advancements in Flame-Retardant Systems for Rigid Polyurethane Foam

“…Moreover, the combustion of RPUF may result in the emission of toxic smoke and gases, such as carbon monoxide (CO), nitrous oxides (NO x ), and hydrogen cyanide (HCN), which can be hazardous to human health [18]. For this reason, it is crucial to explore flame-retardant RPUF and to expand its practical applications [5,[19][20][21][22][23].…”