非碳化聚合物两种热流吸收模式热解机理

摘要

在之前建立的一维热解模型基础上,对抗冲击性聚苯乙烯(HIPS)和丙烯腈-丁二烯-苯乙烯共聚物(ABS)这两种非碳化聚合物材料在外界辐射热流条件下的热解过程进行数值模拟,研究表面吸收和深度吸收这两种文献中用的较多且相对极端的吸收方式对材料热解过程的影响.模拟锥型量热仪氮气气氛下这两种材料的热解过程,模拟和实验对比参数包括质量损失速率、材料内部温度分布、表面和背面温度.结果表明,不同热流吸收模式对HIPS和ABS热解过程的影响机制与之前PMMA的结论类似,即该模型可以用于非碳化聚合物材料在外界恒定热流惰性气氛下热解过程的模拟.%Thermal degradation of two types of non-charring polymers, high impact polystyrene (HIPS) and Acrylonitrile Butadiene Styrene copolymer (ABS), exposed to an external incident heat flux was numerically investigated based on a previously established one dimensional model.The effects of surface and in-depth absorption on the pyrolysis process of HIPS and ABS were extensively employed in literatures.The corresponding cone calorimetry tests in nitrogen atmosphere of these two polymers were simulated.The experimental and numerical results were compared to validate the developed model, including mass loss rate, temperature distribution in condensed phase, top and bottom surface temperature.Results indicate that the influences of absorption mode of incident heat flux on thermal degradation process of HIPS and ABS are similar to the conclusion of PMMA, which implies that the proposed model can be utilized in predicting the pyrolysis of non-charring polymers in inertial atmosphere with constant external incident heat flux.