Thermally conductive polymers offer new possibilities for the heat dissipation in electric and electronic components, for example, by a three‐dimensional shaping of the heat sinks. To face safety regulations, improved fire performance of those components is required. In contrast to unfilled polymers, those materials exhibit an entirely different thermal behavior. To investigate the flammability, a phosphorus flame retardant was incorporated into thermally conductive composites of polyamide 6 and hexagonal boron nitride. The flame retardant decreased the thermal conductivity only slightly. However, the burning behavior changed significantly, due to a different heat propagation, which was investigated using a thermographic camera. An optimum content of hexagonal boron nitride for a sufficient thermal conductivity and fire performance was found between 20 and 30 vol%. The improvement of the fire performance was due to a faster heat release out of the pyrolysis zone and an earlier decomposition of the flame retardant. For higher contents of hexagonal boron nitride, the heat was spread faster within the part, promoting an earlier ignition and increasing the decomposition rate of the flame retardant.

中文翻译：

---

PA6和六方氮化硼在导热聚合物中的热传播

导热聚合物为电气和电子组件的散热提供了新的可能性，例如，通过对散热器进行三维造型。为了遵守安全法规，需要提高这些组件的防火性能。与未填充的聚合物相比，这些材料表现出完全不同的热行为。为了研究可燃性，将磷阻燃剂掺入聚酰胺6和六方氮化硼的导热复合材料中。阻燃剂仅略微降低了热导率。但是，由于热传播不同，燃烧行为发生了显着变化，这已通过热像仪进行了研究。为获得足够的导热性和防火性能，发现六方氮化硼的最佳含量为20％至30％（体积）。防火性能的提高归因于更快的热量释放出热解区和更早地分解了阻燃剂。对于较高含量的六方氮化硼，热量会在零件内散布得更快，从而促进更早着火并提高阻燃剂的分解速率。