聚氨酯和聚苯乙烯热解前后的结构演变  

Structural evolutions of polyurethane and polystyrene foam materials before and after pyrolysis

作　　者：徐磊[1] 韩雪峰[1] 尤飞[1] 胡银[1] 王佳鑫[1] 

机构地区：[1]南京工业大学城市建设与安全工程学院,江苏南京210009

出　　处：《消防科学与技术》2012年第2期118-121,共4页Fire Science and Technology

基　　金：国家自然科学基金项目(50906039)

摘　　要：以软质聚氨酯泡沫和聚苯乙烯泡沫颗粒两种典型多孔材料为试验对象,对其孔隙率、孔径分布、表观密度和堆积密度等结构特性参数及表面微观形貌进行了测算和表面扫描电镜(SEM)表征,研究不同热解程度材料结构特性演变与阴燃建立和传播趋势之间的关系。结果表明:软质聚氨酯泡沫结构尺寸更大,整体更为疏松,受热成炭后呈现轮廓清晰的细削骨架,孔隙硕大且畅通,氧气完全自由输运,热量传递更直接,更易建立阴燃、维持传播并实现向明火的转化;相对而言,聚苯乙烯泡沫颗粒孔径较为细小,受热后成炭显著,孔径尺寸减小,空气气流量和氧气容纳量大大减少,不易建立阴燃过程。The flexible polyurethane foam and polystyrene foam particles were selected as two typical porous material. In order to explore the relationship hetween structural evolutions with different pyrolysis degrees and the establishment and propaga- tion trends of smoldering, the structural parameters like porosi- ty, distribution of pore sizes, apparent density and stacking density were calculated, and the microscopic morphology was eharacterised. Results showed that the flexible polyurethane foam have larger pores and looser structure, while polystyrene foam particles have fine pores. After heated and charred, poly- urethane foam show clear thin frames, big and open pores, in which oxygen can he freely transported and heat can be trans- ferred directly, hence smoldering can be more easily estab- lished, propagated and converted to flaming; in contrast, for polystyrene foam particle, char formation is strong and pore si- zes are decreased much, in which air volume and oxygen carring capacity is greatly limited, hence smoldering is more difficult to be established.

关 键 词：阴燃热解程度 微观形貌 结构特性 软质聚氨 酯泡沫 聚苯乙烯泡沫 

分 类 号：X913.4[环境科学与工程—安全科学] TQ328[化学工程—合成树脂塑料工业]