The tris(hydroxymethyl)aminomethane (THAM) and its derivative (DHD 2-([1,3-dihydroxypropan-2-ylidene]amino)-2-(hydroxymethyl)propane-1,3-diol) have been used as organic thermal stabilizers for flexible poly(vinyl chloride) (PVC). According to dehydrochlorination and discoloration tests conducted at 180°C, THAM showed to be an excellent organic thermal stabilizer for flexible PVC, not only THAM stabilizer improved the thermal stability of PVC but also maintained the initial color of the PVC. The induction time and the thermal stability time were 52 and 55.5 min, respectively. DHD can also be used as an organic thermal stabilizer for flexible PVC; however, its thermal stabilizing efficiency was not satisfactory, but it has a good synergistic effect with traditional cadmium–zinc soap stabilizers. Besides, the experiments had been performed to investigate pentaerythritol (PER) and THAM, two substances with similar structure, but such a huge difference in thermal stabilizing efficiency for flexible PVC. THAM did improve the thermal stability of PVC, both in initial whiteness and long-term thermal stability. But PER has no thermal stabilizing efficiency for PVC when used alone. At the end of the article, the probable mechanism which can give an explanation for the stabilizing efficiency given by the THAM has been proposed.

中文翻译：

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三(羟甲基)氨基甲烷及其衍生物作为柔性聚氯乙烯的有机热稳定剂

三(羟甲基)氨基甲烷 (THAM) 及其衍生物 (DHD 2-([1,3-dihydroxypropan-2-ylidene]amino)-2-(hydroxymethyl)propane-1,3-diol) 已被用作有机热柔性聚氯乙烯 (PVC) 的稳定剂。180℃脱氯化氢和变色试验表明，THAM是一种优良的软质PVC有机热稳定剂，不仅提高了PVC的热稳定性，而且保持了PVC的初始颜色。诱导时间和热稳定时间分别为 52 和 55.5 分钟。DHD还可用作软质PVC的有机热稳定剂；但其热稳定效果并不理想，但与传统的镉锌皂稳定剂有很好的协同作用。除了，该实验旨在研究季戊四醇 (PER) 和 THAM，这两种物质具有相似的结构，但在柔性 PVC 的热稳定效率方面存在巨大差异。THAM 确实提高了 PVC 的热稳定性，包括初始白度和长期热稳定性。但PER单独使用时对PVC没有热稳定效果。在文章的最后，提出了可以解释 THAM 给出的稳定效率的可能机制。