几种阻燃剂对木材燃烧全过程的影响研究

Influence of Flame Retardants on the Whole Process of Wood Combustion

摘要: 针对阻燃剂对木材燃烧全过程影响不明确的问题，基于热裂解仪–色质联用分析仪、锥形热量仪和电镜的耦合开展了多聚磷酸铵(APP)、磷酸二氢铵(NH4H2PO4)和硼酸(H3BO3)对水曲柳燃烧全过程的影响分析。结果表明：阻燃剂的阻燃效果是通过热裂解、燃烧和熄灭阶段的综合表现确定的。APP、NH4H2PO4和H3BO3的添加都促进了热裂解过程呋喃类物质的形成，抑制了小分子产物如乙酸和酚类物质的形成，导致燃烧阶段的最大热释放速率分别下降27.9%、32.3%和36.8%，但着火时间却从原样的250 s缩短至20~30 s。由于阻燃剂的浓度较低，其阻燃效果不太理想，但从残渣的形态分析发现阻燃剂处理样品的燃烧残渣的纤维结构破坏没有水曲柳原样明显，尤其是APP处理样品的残渣，其碎片结构是粘结在一起，阻燃效果最好。

Abstract: In order to fully investigate the influence of flame retardants on wood combustion, an experimental method was used in combination with a pyrolyzer coupled with chromatography-mass spectrometry (Py-GC/MS), a cone calorimeter test (CCT) and SEM. The whole process of wood combustion was studied with the addition of APP, NH4H2PO4 and H3BO3. It was found that flame retardant efficiency should be evaluated by the comprehensive behaviors of pyrolysis, combustion and extinction stage. The existence of APP, NH4H2PO4 and H3BO3, promotes the formation of furan compounds, and inhibits the formations of small-molecular-weight compounds (such as acetic acid) and phenols during Manchurian ash pyrolysis. As a result, the maximum heat release rate in the combustion stage decreases by 27.9%, 32.3% and 36.8% respectively, but the ignition time is shortened from the original 250s to 20 - 30 s. Due to the low concentration of flame retardant, its flame retardant effect is not ideal. However, it is found that the fiber structure of samples treated with flame retardant is not as damaged as the original sample observed form analysis of the residues. The debris structure of the residue from APP treated sample is bonded together. Among the three flame retardant, the effect of APP is the best after the whole combustion process analysis.