用锥形量热仪研究聚乙烯膨胀阻燃体系的燃烧性

利用锥形量热仪在50kW·m^-2热辐照条件下,研究了含淀粉膨胀阻燃线性低密度聚乙烯(LLDPE)体系的燃烧性,获得了最大热释放速率、总热释放、有效燃烧热、最大烟产生速率、总烟释放量及质量损失速度等参数.实验结果表明:含淀粉膨胀阻燃剂能明显降低LLDPE的热释放速率、总热释放和有效燃烧热,淀粉作为膨胀型阻燃剂中的成炭剂,可以部分代替季戊四醇,而对热释放速率影响不大,达到了阻燃和降低成本的目的.该膨胀体系使烟释放变得缓慢,但总烟释放量明显增大.在燃烧时使LLDPE更早地发生热降解,但热降解速度变得缓慢.

An Investigation of Flammability of Intumescent Flame Retardant Polyethylene Containing Starch by Using Cone Calorimeter

The behaviour of flammability of linear low density polyet hylene(LLDPE)treated with The int umescent flame retardant containing starch has been investigated by using cone calorimeter at incidenTheat flux of 50kW·m^-2in this paper.Based upon The parameters, such as peak heat release rate(p k-HRR), total heat release(THR), effective heatof combustion (EHC), peak smoke production rate(pk-SPR), total smoke production(TSP)and mass loss rate (MLR), etc.taken from The cone calorimeter, some results were obtained as follows:Firstly, starch-containing intumescent flame retardant(S-IFR) obviously lowered pk-HRR, THR and EHC, i.e., 485 kW·m^-2, 905kJ, 33.2 MJ·kg^-1respectively for LLDPE/S-IFR, 1951kW ·m^-2, 1019 kJ, 44.7MJ·kg^-1for LLDPE. pk-HRR increased slightly with increasing the percentage of starch in char forming agent s;secondly, S-IFRmade pk-SPR of LLDPE becomelower, however, it significantly enhanced TSP at The end of combustion;finally, S-IFR promot-ed The Thermal degradation of LLDPEearlier, and made The rate of Thermal degradation lower.