Beschreibung:
To study the combustion characteristics and fire hazard of polystyrene building exterior wall thermal insulation materials, the combustion, fire, and pyrolysis characteristics of thermosetting polystyrene (TPS) insulation, graphite polystyrene (GEPS), and expanded polystyrene (EPS) are compared and analyzed using a cone calorimeter and a thermogravimetric analyzer. From the structure and flame retardant components of thermal insulation board, their flame retardant mechanisms are described. Results show that in a nitrogen atmosphere, the pyrolysis range is 30 °C–600 °C. Only one weight loss stage in EPS and GEPS and two weight loss stages in TPS are observed. TPS has short ignition time, low fire performance index, and high fire growth index. This result indicates that TPS has the characteristics of good flammability, easy to explode, and sensitive to heat. The smoke generation rate, the peak heat release rate, total smoke production, and oxygen consumption of TPS are lower than those of EPS and GEPS. Moreover, no melt drop occurs during the combustion process, and the appearance structure remains intact after combustion, which prevents the occurrence of secondary fire. Comparison of various indexes presents that the flammability and fire risk of TPS are evidently better than those of EPS and GEPS