In this paper, an effective flame retardant consisting of hierarchical magnesium hydrate (MH) nanosheets doped with molybdenum trioxide nanoparticles (MO@MH) was successfully synthesized via a hydrothermal process. Then, MO@MH, MH, and MH/MO were respectively incorporated into flexible polyvinyl chloride (fPVC) to prepare a series of composites via melt blending. The results of limiting oxygen index (LOI), UL‐94, and cone calorimetry test showed that MO@MH exhibited better flame retardancy and smoke suppression than MH and MH/MO due to the synergistic effect of MO and MH, and the hierarchical structure of MO@MH. With the addition of 20 phr MO@MH, LOI value of fPVC was increased from 23.9% to 33.8% , and UL‐94 reached V0 rating. The peak heat release rate, total heat release, peak smoke production rate, and total smoke production were decreased to 143.0 kW/m², 44.9 MJ/m², 0.0093 m²/s and 29.4 m², respectively. The thermogravimetric analysis results suggested that MO@MH greatly promoted the dehydrochlorination of fPVC at lower temperature, so that more compact and continuous char residues were formed. The Fourier transform infrared spectroscopy results indicated that MO@MH can prevent chain scission and oxidation of fPVC carbonaceous backbone, and as a result less smoke was released.

中文翻译：

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柔性聚氯乙烯中三氧化钼掺杂水合镁的阻燃性和抑烟性

本文通过水热法成功合成了由三水氧化钼纳米颗粒（MO @ MH）掺杂的水合氢氧化镁（MH）纳米片组成的有效阻燃剂。然后，将MO @ MH，MH和MH / MO分别掺入柔性聚氯乙烯（fPVC）中，通过熔融共混制备一系列复合材料。极限氧指数（LOI），UL‐94和锥形量热法测试的结果表明，由于MO @ MH的协同作用以及层次结构，MO @ MH的阻燃性和抑烟性均优于MH和MH / MO MO @ MH。通过添加20 phr MO @ MH，fPVC的LOI值从23.9％增加到33.8％，UL-94达到V0等级。峰值放热率，总放热，峰值烟雾产生率，²，44.9 MJ /米²，0.0093米² /秒和29.4米²分别。热重分析结果表明，MO @ MH在较低的温度下大大促进了fPVC的脱氯化氢作用，从而形成了更致密和连续的炭渣。傅里叶变换红外光谱结果表明，MO @ MH可以阻止fPVC碳质骨架的断链和氧化，因此释放出的烟雾较少。