State Key Laboratory of Fire Science, University of Science and Technology of China, Jinzhai Road 96, Hefei, Anhui 230026, China.
J Hazard Mater. 2013 Nov 15;262:9-15. doi: 10.1016/j.jhazmat.2013.08.024. Epub 2013 Aug 19.
A medium-scale melting experiment rig was designed and constructed in this study. A detailed experimental study was conducted on the melting behavior and the chemical kinetic characteristics of three typical thermoplastic materials, including polypropylene (PP), polyethylene (PE) and polystyrene (PS). It is observed that the thermal decomposition of the thermoplastic materials mainly consists of three stages: the initial heating stage, the melting-dominated stage and the gasification-dominated stage. Melting of the materials examined takes place within a certain temperature range. The melting temperature of PS is the lowest, moreover, it takes the shortest time to be completely liquefied. To quantitatively represent the chemical kinetics, an nth-order reaction model was employed to interpret the thermal decomposition behavior of the materials. The calculated reaction order is largely in accordance with the small-scale thermal gravimetric analysis (TGA). The small difference between the results and TGA data suggests that there are some limitations in the small-scale experiments in simulating the behavior of thermoplastic materials in a thermal hazard. Therefore, investigating the thermal physical and chemical properties of the thermoplastic materials and their thermal hazard prevention in medium or large-scale experiments is necessary for the fire safety considerations of polymer materials.
本研究设计并构建了一个中型规模的熔融实验装置。对三种典型热塑性材料（聚丙烯（PP）、聚乙烯（PE）和聚苯乙烯（PS））的熔融行为和化学动力学特性进行了详细的实验研究。结果表明，热塑性材料的热分解主要包括三个阶段：初始加热阶段、熔融主导阶段和气化主导阶段。所研究材料的熔融发生在一定的温度范围内。PS 的熔融温度最低，而且它最快被完全液化。为了定量表示化学动力学，采用 n 阶反应模型来解释材料的热分解行为。计算得到的反应级数与小尺度热重分析（TGA）基本一致。结果与 TGA 数据之间的微小差异表明，在模拟热危害中热塑性材料行为时，小尺度实验存在一些局限性。因此，对于聚合物材料的消防安全考虑，有必要在中型或大型实验中研究热塑性材料的热物理和化学性质及其热危害预防。
