The present work investigates the fire retardancy mechanisms of ammonium polyphosphate (APP) and aluminium diethyl phosphinate salt (AlPi) in an acrylonitrile-butadiene-styrene copolymer (ABS) by analysing the pyrolysis, flammability and fire behaviour. Evidences of synergy in flammability by combining both flame retardants were discussed and related to the flame retardant mechanisms assessed by means of TGA and FT-IR analysis of the pyrolysis gases. Specifically, the ABS flame retardant formulation with a 12.5 wt% APP and 12.5 wt% AlPi (ABS-APP/AlPi) reached a UL-94 V-0 classification, unlike the ABS with 25 wt% APP (ABS-APP) and ABS with 25 wt% AlPi (ABS-AlPi) formulations, which completely burned. Under forced flame conditions, APP and AlPi showed, respectively, a main condensed and gas phase-based mode of action in the ABS matrix, whereas, a combined gas and condensed mode of action was identified when both additives were simultaneously incorporated. Also, the ABS-APP/AlPi formulation showed the higher reduction of the peak heat release rate (74%) and of the maximum average rate of heat emission (65%), obtained from cone calorimeter tests. As well as, a more protective fire residue with an improved microstructure assed by SEM.

本工作通过分析热解，可燃性和着火行为，研究了丙烯腈-丁二烯-苯乙烯共聚物（ABS）中多磷酸铵（APP）和次膦酸铝二乙酯（AlPi）的阻燃机理。讨论了通过将两种阻燃剂组合使用而在可燃性方面产生协同增效的证据，并且这些证据与通过热解气体的TGA和FT-IR分析评估的阻燃机理有关。具体而言，具有12.5 wt％APP和12.5 wt％AlPi（ABS-APP / AlPi）的ABS阻燃剂配方达到UL-94 V-0分类，与具有25 wt％APP（ABS-APP）和ABS的ABS不同具有25 wt％的AlPi（ABS-AlPi）配方，可完全燃烧。在强制火焰条件下，APP和AlPi分别在ABS基质中显示出主要的冷凝和基于气相的作用方式，而 当同时加入两种添加剂时，鉴定出了气体和冷凝作用的组合模式。而且，ABS-APP / AlPi配方显示出通过锥形量热仪测试获得的峰值放热率（74％）和最大平均放热率（65％）的更大降低。以及，通过SEM评估，具有改善的微观结构的更具保护性的火渣。