用CONE法研究ULDM的阻燃特性

采用硼、氮-磷、硅和卤素系4种组分复合的无机阻燃剂制备难燃超轻质木纤维发泡材料(ULDM),通过锥形量热仪(CONE)法对超轻质木纤维发泡材料独特的燃烧热解特点、燃烧过程的热释放及阻燃剂各组分协效作用进行研究。结果表明,超轻质木纤维发泡材料的燃烧热解有不同于其他木质材料的爆燃现象,放热集中且迅速,瞬间放热量高。经无机复合阻燃处理后的超轻质木纤维发泡材料有焰燃烧时间低于30 s,在火场高温中能够维持阴燃状态,燃烧热解进程缓和,放热平稳。证明了复合阻燃剂各组分可充分产生协效阻燃作用,硼系能迅速形成玻璃态隔离层,氮-磷系能促进脱水成炭,硅系能有效增强纤维和炭层热稳定性,卤素系能极大降低有效燃烧热。

Fire Retardant Properties of Ultra-Low Density Wood Fiber-Based Foaming Material by Cone Calorimeter

The ultra-low density wood-based foaming material(ULDM),density in 0.03～0.09 g·cm^-3,was prepared by liquid foaming process. Four inorganic components were used as fire retardants to prepare flame retardant ULDM,including boron,nitrogen-phosphorus,silicon and halogen type.By means of cone calorimeter,the ULDM were systematically investigated from the aspects of their unique characters of pyrolysis,combustion,heat release in the combustion process.The fire retardant mechanism and fire retardant components synergism were analyzed.The pyrolysis and combustion of ULDM had the deflagration phenomenon,different from other wood materials.The flame combustion time was less than 30 s,smoldering state could maintain in high temperature when the ULDM were dealt with inorganic composite flame retardants.Research also testified that the composite flame retardant components could produce synergistic effects.Boron could rapidly form glassy isolation layer,nitrogen-phosphorus could promote the dehydration and carbon formation,silicon could effectively enhance the thermal stability of carbon and fiber,and halogen type could greatly reduce the effective heat of combustion.