The effects of the modified layered double hydroxide (LDH) of Co/Al (OCoAl‐LDH) and the modified LDH of Co/Fe (OCoFe‐LDH) on the combustion behaviors of polyvinyl chloride (PVC) during pyrolysis processes were compared and investigated. The thermal degradation and combustion behavior of the PVC composites were investigated by thermogravimetric analysis (TGA), microscale combustion calorimetry (MCC), and cone calorimetry (CONE). The results indicate that the incorporation of LDHs brought about the improved thermal stability and reduced heat release of PVC composites at a high temperature. The smoke‐suppression properties of the composites are investigated by steady‐state tube furnace (SSTF), and the results indicated that the toxic gases such as CH₄, CO, and N_xO were inhibited by both of the two LDHs, but the OCoFe‐LDH has a better effect on the smoke suppression. Subsequently, the char layer was investigated by scanning electron microscopy–energy‐dispersive spectrometry (SEM‐EDS) and Raman analysis. The results indicate that the LDHs can promote the dechlorination of PVC during the thermal oxidation process and can inhibit the production of HCl in inert gas. Generally, OCoAl‐LDH and OCoFe‐LDH can be potential catalysts for waste disposal and can improve the fire safety of PVC.

中文翻译：

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OCoAl-LDH和OCoFe-LDH对聚氯乙烯燃烧行为的影响

比较和研究了Co / Al的改性层状双氢氧化物（OCoAl-LDH）和Co / Fe的改性LDH（OCoFe-LDH）对热解过程中聚氯乙烯（PVC）燃烧行为的影响。通过热重分析（TGA），微尺度燃烧量热法（MCC）和锥形量热法（CONE）研究了PVC复合材料的热降解和燃烧行为。结果表明，LDHs的引入带来了高温下PVC复合材料的改进的热稳定性和减少的热释放。通过稳态管式炉（SSTF）研究了复合材料的抑烟性能，结果表明有毒气体如CH ₄，CO和N _xO被两个LDH均抑制，但是OCoFe-LDH对烟雾抑制效果更好。随后，通过扫描电子显微镜–能量色散光谱（SEM-EDS）和拉曼分析研究了焦炭层。结果表明，LDHs可以促进热氧化过程中PVC的脱氯，并可以抑制惰性气体中HCl的产生。通常，OCoAl-LDH和OCoFe-LDH可能是废物处置的潜在催化剂，并可以提高PVC的防火安全性。