聚磷酸铵-淀粉对木粉／聚苯乙烯复合材料的阻燃作用

利用锥形量热仪分析了聚磷酸铵(APP)-淀粉阻燃体系在木粉/聚苯乙烯复合材料(WF-PS)中的阻燃作用。结果表明,添加APP能有效降低WF-PS的热释放速率(HRR)和总热释放量(THR),增加成炭量,延长点燃时间(TTI),表现出显著的阻燃作用;APP对WF-PS的有效燃烧热影响不大,说明APP的阻燃作用为凝聚相机理,成炭是该机理的重要方面;添加淀粉作为APP的辅助成炭剂,能够提高阻燃效率并减少APP用量,APP-淀粉是WF-PS复合材料的有效膨胀型阻燃体系。APP-淀粉的添加对WF-PS的力学性质有一定不利影响,但是当APP用量在10%以下、淀粉用量2%以下时,WF-PS可保持良好的力学性能。

The Fire Retardancy of Wood Flour/PS Composites Treated with APP-Starch

The fire retardancy of wood-flour/polystyrene composites(WF-PS) treated by ammonium polyphosphate(APP)-starch was studied by using a cone calorimeter.The results show that under a heat flux of 35 kW/m2,the heat release rate and the total heat release are decreased obviously while the charring is drastically increased and the time to ignition is prolonged by the addition of APP,however no significant influence on the effective heat of combustion is observed,this suggests the condensed phase fire retardant mechanism of APP in which the catalytic charring effect of APP on wood shall be very important.Adding starch as a charring agent is effective to improve the fire performance of APP,and APP-starch is an effective intumescent fire-retardant system to WF-PS.APP-starch system has negative effects on the mechanical properties of WF-PS,however it is minor when the dosage of APP is under 10% and starch is under 2%.