Abstract Aliphatic polymers such as polyethylene or polypropylene are widely used in spite of their high flammability and forces the introduction of flame retardants (FR), e.g. metal phosphinates, into the polymers. These flame retardants usually act in the condensed phase or may influence the gas phase mechanism of combustion. However, the modes of action are not yet understood in detail and require increasing research. In this study a contribution to the latter is made. The thermal decomposition behavior of aluminum diethylphosphinate (AlPi) as FR, mixed in ultra-high molecular weight polyethylene (UHMWPE) is investigated here by molecular beam mass spectrometry (MBMS) in an oxygen-free atmosphere. The isothermal pyrolysis experiments for this system have been systematically studied by first concentrating on each neat compound, FR and polymer, respectively, followed by the analysis of doped polyethylene blends. The aim is to detect phosphorus-containing species in the gas phase, which is the minimum requirement for a gas phase active FR. It was found that the main product of AlPi is diethylphosphinic acid, which subsequently degrades to lighter species or dimerizes. In the mixture, although the AlPi decomposition is influenced by the polymer in the condensed phase, most of the species responsible for a flame suppressant effect are still present in the gas phase.

中文翻译：

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二乙基次膦酸铝作为阻燃添加剂掺入超高分子量聚乙烯的等温热解研究

摘要 脂肪族聚合物，例如聚乙烯或聚丙烯，尽管它们具有高可燃性，但仍被广泛使用，并迫使在聚合物中引入阻燃剂 (FR)，例如金属次膦酸盐。这些阻燃剂通常在凝聚相中起作用或可能影响燃烧的气相机理。但是，尚未详细了解其作用模式，需要进行更多的研究。在这项研究中，对后者做出了贡献。在无氧气氛中通过分子束质谱法 (MBMS) 研究了混合在超高分子量聚乙烯 (UHMWPE) 中的二乙基次膦酸铝 (AlPi) 作为 FR 的热分解行为。系统地研究了该系统的等温热解实验，首先关注每种纯化合物、FR 和聚合物，分别对掺杂聚乙烯共混物进行分析。目的是检测气相中的含磷物质，这是气相活性 FR 的最低要求。发现AlPi的主要产物是二乙基次膦酸，其随后降解为较轻的物质或二聚化。在混合物中，虽然 AlPi 的分解受到凝聚相中聚合物的影响，但大多数起阻燃作用的物质仍然存在于气相中。