Abstract This work examines the effect of Layered Double Hydroxides (LDHs), Expandable Graphite (EG) and Ammonium Polyphosphate (APP) on the thermal stability and behaviour under fire conditions of polyisocyanurate (PIR) insulation foams. Virgin materials’ and char residues’ morphologies were analyzed with a variety of experimental techniques including field emission scanning electron and optical microscopy along with Raman spectroscopy. Thermal stability and burning behaviour were examined using thermogravimetric (TGA) coupled with Fourier Transform Infrared (FTIR) spectrometer and cone calorimeter. TGA results suggested a decrease in degradation temperature upon introduction of fillers in PIR samples. FTIR spectra were used to determine the absorbance intensity of the different pyrolysis gases. Cone calorimeter data analysis established a limited effect on reducing the rate of heat release rate and smoke production with the inclusion of LDHs. However, EG or EG + APP addition, caused a considerable decrease in heat release rate, owing to the increased char strength and the release of non-combustible gases. The positive effect of EG or EG + APP in the fire behaviour of PIR foams was further supported by the morphological evaluation of their residual char samples.

中文翻译：

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层状双氢氧化物、膨胀石墨和聚磷酸铵添加剂对聚异氰脲酸酯保温泡沫热稳定性和防火性能的影响

摘要 这项工作研究了层状双氢氧化物 (LDH)、可膨胀石墨 (EG) 和多磷酸铵 (APP) 对聚异氰脲酸酯 (PIR) 绝缘泡沫在火灾条件下的热稳定性和行为的影响。使用各种实验技术分析原始材料和炭残留物的形态，包括场发射扫描电子和光学显微镜以及拉曼光谱。使用热重 (TGA) 结合傅立叶变换红外 (FTIR) 光谱仪和锥形量热仪检查热稳定性和燃烧行为。TGA 结果表明在 PIR 样品中引入填料后降解温度降低。FTIR 光谱用于确定不同热解气体的吸收强度。锥形量热仪数据分析表明，加入 LDH 对降低热释放率和烟雾产生率的影响有限。然而，EG或EG+APP的加入，由于炭强度增加和不燃气体的释放，导致放热率显着降低。EG 或 EG + APP 对 PIR 泡沫的防火性能的积极影响得到了其残留炭样品的形态评估的进一步支持。