基于次磷酸铝的高抗冲聚乳酸材料的阻燃改性

Flame-Retardance Modification of High-Impact Polylactide

针对高抗冲聚乳酸材料阻燃性差的缺点,文中以次磷酸铝(AP)为阻燃剂,研究了其对聚乳酸、聚碳酸酯、抗冲改性剂和增容剂构成的高抗冲材料PLA-PC/ADR/BPM的阻燃性能、燃烧性能和热分解行为的影响。结果表明,AP有效改善了PLA-PC/ADR/BPM的阻燃性能。当AP为19 phr时,PLA-PC/ADR/BPM通过样品厚度为3.2 mm时的垂直燃烧V-0级,氧指数达29.5%。同时,锥形量热测试结果显示,19 phr的AP使PLA-PC/ADR/BPM材料燃烧过程中热释放速率峰值、总烟释放、总热释放均出现明显下降,而高温700℃的残余物质量显著上升。热分析结果证明,PLA-PC/ADR/BPM中引入AP后,材料的热分解行为在410～550℃范围内产生显著变化,AP使得材料高温热稳定性明显提高。结合燃烧测试和热分析测试结果证明,AP可有效改善高抗冲聚乳酸PLA-PC/ADR/BPM的阻燃性能,且燃烧过程中固相阻燃作用明显。

On the basis of the poor flame retardance of high-impact polylactide (PLA), this work focused on the flame retardance, combustion performance, and thermally decomposing behavior of high-impact PLA-PC/ADR/BPM consisting of PLA, polycarbonate (PC), methacrylate styrene copolymer as impact modifier (ADR), and compatibilizer with BPM (polymethylmethacrylate as shell and polybutylacrylate as core) and studied effects of aluminum hypophosphite (AP) on the several performances mentioned above. The experimental results confirm that the AP is efficient in improving the flame retardance of PLA-PC/ADR/BPM. When the content of AP is 19 phr, the PLA-PC/ADR/BPM passes the V-0 rating in vertical test in the case of the sample thickness of 3.2 mm and achieves the oxygen index of 29.5%. Meanwhile, the cone calorimeter result shows that the peak of heat release rate, total heat release, and total smoke production of PLA-PC/ADR/BPM are decreased after incorporation of 19 phr of AP, while the residue at 700 ℃ increases in this case. The thermal analysis result illustrates that the thermal decomposing behavior of PLA-PC/ADR/BPM is obviously affected by the addition of AP, especially in the temperature range of 410~550 ℃. Both combustion performance and thermal analysis demonstrate that the addition of AP efficiently promotes the flame retardance of PLA-PC/ADR/BPM and its condense phase plays an important role in flame retardance of PLA-PC/ADR/BPM/AP.