聚丙烯膨胀成炭行为对裂解燃烧过程的影响

对膨胀阻燃聚丙烯材料在锥形量热仪试验条件下的燃烧过程进行了研究，分析了材料膨胀成炭行为对裂解燃烧过程的影响。测量了纯聚丙烯及膨胀阻燃聚丙烯在膨胀燃烧过程中的质量损失速率、热释放速率和炭层膨胀高度随时间变化规律。分析了膨胀高度、膨胀速度、炭层结构对裂解燃烧的影响。结果表明，随着膨胀阻燃剂添加量的增加，膨胀升高的速度有加快的趋势；随着外部辐射功率的加大，膨胀速度加快。聚丙烯材料的炭层整体性越强，炭层结构越致密，阻隔效果越好，热释放速率越低。通过对材料膨胀成炭过程的理论分析也验证了膨胀高度（或膨胀速度）和炭层的结构都对裂解燃烧过程有很大的影响。

Effect of Intumescence and Char Formation on Pyrolysis and Combustion for Polypropylene Materials

The combustion process of the intumescent fire-retardant polypropylene were studied by the cone calorimeter. The effects of behavior of intumescence and char forming on pyrolysis and combustion for polypropylene materials were analyzed. The mass loss rates, heat release rates of the intumescent polypropylene and pure polypropylene during burning were measured and the intumescence height of intumescent polypropylene was recorded at the same time. The effects of intumescence height, intumescence velocity and char structure on pyrolysis and combustion were investigated. The results show that intumescence height increases faster with the increasing amount of intumescence fire retardant. The intumescence velocity increases with the increasing amount of incident heat flux. The heat release rates become lower when the char layer becomes more unity and densification, the char layer insu- lates heat better accordingly. The serious effect of intumescence and char structure on burning process is also validated by the theoretical analysis of intumescence and char formation.