Polymers are usually known for their low thermal conductivity. However, the demand in industries for polymers with high thermal conductivity has increasingly grown due to their low density, low cost, flexibility, and good environmental resistance compared with conventional substances of high thermal conductivity. Composites filled with high thermal conductivity nanofillers will increase thermal conductivity (k); however, it has been clearly observed that the mechanical properties will deteriorate along with this process. Instead, increasing the intrinsic thermal conductivity of polymers themselves is more important. This review focuses on the mechanism of increasing k from the perspectives of polymer intrinsic structure tailoring: crystallinity, orientation of the crystallites, crystalline grain size, and alignment of the molecular chain in the amorphous region. Structure tailoring methods of increasing/improving these four factors are critically reviewed and discussed. Accurate thermal characterization methods are critically reviewed for these structure-tailored polymers in low dimensions. The transient electro-thermal and pulsed laser-assisted thermal relaxation 2 techniques provide some of the best and most accurate thermal conductivity measurements with high physics control.

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通过结构剪裁提高聚合物的导热率

聚合物通常因其低导热性而闻名。但是，与传统的高导热性物质相比，由于其低密度，低成本，柔韧性和良好的耐环境性，对高导热性聚合物的工业需求日益增长。填充有高导热率纳米填料的复合材料将提高导热率（k）；然而，已经清楚地观察到，机械性能将随着该过程而劣化。相反，增加聚合物本身的固有热导率更为重要。这篇综述着重于增加k的机制从聚合物固有结构调整的角度来看：结晶度，微晶的取向，晶粒尺寸和非晶区分子链的排列。严格审查和讨论了增加/改善这四个因素的结构定制方法。对于这些尺寸定制的低尺寸聚合物，准确的热表征方法进行了严格的审查。瞬态电热和脉冲激光辅助热弛豫2技术可在高度物理控制下提供一些最佳和最精确的热导率测量。