Abstract In this study, a facile solvothermal approach for preparing anhydrous manganese hypophosphite (A-MnHP) microtubes was demonstrated for the first time by using manganese chloride and hypophosphorous acid in mixed solvents, followed by fabricating A-MnHP-based poly(lactic acid) (PLA) composites via a melt-blending method. Owing to the unique morphology of A-MnHP, the tensile strengths of the PLA composites with 1 wt%, 5 wt% and 10 wt% A-MnHP are approximately 17%, 7% and 3% higher than those of neat PLA, respectively. Compared to neat PLA, PLA composite containing 15 wt% A-MnHP (PLA/A-MnHP15) exhibited lower peak heat release rate (50% reduction), total heat release (13% reduction), peak CO2 and CO productions (50% and 53% reductions), which also passed UL 94 V-2 rating test with high limiting oxygen index (27.5%). The combustion temperature change during the cone calorimeter tests showed that PLA/A-MnHP15 showed the lowest combustion temperature, achieving the best fire safety performance. Residue analysis indicated that the presence of A-MnHP resulted in the formation of continuous and compact char residues composed of aromatic structure and phosphorous-rich inorganic structure, retarding the permeation of heat, oxygen transfer and escape of volatile degradation products.

中文翻译：

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用于同时对聚乳酸进行阻燃和机械增强的无水次磷酸锰微管的合成

摘要 在本研究中，首次展示了在混合溶剂中使用氯化锰和次磷酸制备无水次磷酸锰 (A-MnHP) 微管的简便溶剂热方法，随后制备了 A-MnHP 基聚乳酸。 (PLA) 复合材料通过熔融共混方法。由于 A-MnHP 的独特形态，1 wt%、5 wt% 和 10 wt% A-MnHP 的 PLA 复合材料的拉伸强度分别比纯 PLA 高约 17%、7% 和 3% . 与纯 PLA 相比，含有 15 wt% A-MnHP (PLA/A-MnHP15) 的 PLA 复合材料表现出较低的峰值放热率（降低 50%）、总放热率（降低 13%）、峰值 CO2 和 CO 产量（50%和 53% 的减少），它还通过了 UL 94 V-2 等级测试，具有高极限氧指数（27.5%）。锥形量热仪测试过程中的燃烧温度变化表明，PLA/A-MnHP15 表现出最低的燃烧温度，实现了最佳的防火安全性能。残留分析表明，A-MnHP 的存在导致形成由芳香结构和富磷无机结构组成的连续致密的炭残留，阻碍了热量的渗透、氧气的传递和挥发性降解产物的逸出。