Abstract The interactions between kaolinite and a commercially available phosphinate-based flame retardant (Exolit® OP1311) were evaluated as flame retardant systems in Polyamide 6 (PA6). The thermal degradation and flammability of PA6 composites were studied by TGA and cone calorimeter tests. Characterizations were conducted using FTIR, EDX and XRD. Cone calorimeter results showed a reduction in peak heat release rate (pHRR) as a function of filler loading and type with a greater reduction for OP1311 containing composites. Interestingly, OP1311 can be partially substituted by kaolinite without detrimental effect on peak of release rate (pHRR) measured by cone calorimeter. FTIR, EDX and XRD analysis of cone calorimeter residues showed that kaolinite may trap some phosphorous compounds in condensed phase leading to the formation of a glassy structure on sample residue. To assess possible interactions between kaolinite and phosphinate, a controlled thermal degradation was carried out on kaolinite, OP1311 and kaolinite/OP1311 (50:50) blends. The residues were analyzed by EDX and XRD. Results showed that almost all phosphorous present in the initial sample remains in residue for Kaolinite/OP1311 blend versus only about 60% for OP1311 alone. Also, XRD results showed that during combustion, new crystalline phases can be formed in the sample when kaolinite is combined with OP1311. These results suggest that some interactions between both components may occur and could explain the observed fire behavior of the composites containing kaolinite and phosphinate.

中文翻译：

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聚酰胺 6 中高岭石与次膦酸盐基阻燃剂的相互作用

摘要 高岭石与市售次膦酸盐基阻燃剂 (Exolit® OP1311) 之间的相互作用被评估为聚酰胺 6 (PA6) 中的阻燃系统。通过TGA和锥形量热仪测试研究了PA6复合材料的热降解和可燃性。使用 FTIR、EDX 和 XRD 进行表征。锥形量热仪结果显示峰值放热率 (pHRR) 随填料填充量和类型的变化而降低，其中含有 OP1311 的复合材料的降低幅度更大。有趣的是，OP1311 可以被高岭石部分取代，而不会对锥形量热仪测量的释放率峰值 (pHRR) 产生不利影响。红外光谱，锥形量热仪残留物的 EDX 和 XRD 分析表明，高岭石可能会在凝聚相中捕获一些磷化合物，从而在样品残留物上形成玻璃状结构。为了评估高岭石和次膦酸盐之间可能的相互作用，对高岭石、OP1311 和高岭石/OP1311 (50:50) 混合物进行了受控热降解。通过EDX和XRD分析残留物。结果表明，初始样品中存在的几乎所有磷都保留在高岭石/OP1311 混合物的残留物中，而单独的 OP1311 只有约 60%。此外，XRD 结果表明，在燃烧过程中，当高岭石与 OP1311 结合时，样品中会形成新的结晶相。