Polymer thermoelectric (TE) composites have witnessed explosive developments in recent years, arising from their promising prospect for lightweight flexible electronics and capability of harvesting waste-heat. In sharp contrast with intrinsically conducting polymers (CPs), the insulating thermoplastics have seldom been employed as the matrices for flexible TE composites despite their advantages of low costs, controllable melt-flowing behaviors and excellent mechanical properties. Here, we report flexible films of polycarbonate/single-walled carbon nanotube (PC/SWCNT) composites with improved trade-off between TE and mechanical performances. The SWCNTs with 1D nanostructure were dramatically aligned by PC melt-flowing under hot-pressing in the radial direction. The composite maximum power factor reaches 4.8 ± 0.8 μW m⁻¹ K⁻² at 10 wt% SWCNTs in the aligned direction, which is higher than most previously reported thermoplastics-based TE composites at the same SWCNT loading and even comparable to some intrinsically CPs and their composites. In addition, these composites display significantly higher tensile modulus and strength than CPs and their composites. This study paves an effective way to fabricate flexible films of polymer composites with simultaneously high TE and mechanical performances via judicious alignment of SWCNTs in thermoplastic polymers.

聚合物热电（TE）复合材料近年来发展迅猛，这归因于其轻质柔性电子产品的前景广阔以及具有收集余热的能力。与固有导电聚合物（CP）形成鲜明对比的是，尽管绝缘热塑性塑料具有成本低，可控制的熔体流动性能和出色的机械性能的优点，但很少被用作柔性TE复合材料的基质。在这里，我们报告了聚碳酸酯/单壁碳纳米管（PC / SWCNT）复合材料的柔性膜，其在TE和机械性能之间的折衷得到了改善。在径向热压下，PC熔体流动使具有一维纳米结构的SWCNT显着排列。复合最大功率因数达到4.8±0.8μWm ^-1在对齐方向上SWCNT的含量为10 wt％时， K ^-2高于在相同的SWCNT负载下，大多数以前报道的基于热塑性塑料的TE复合材料，甚至与某些固有的CP及其复合材料相当。另外，这些复合材料比CP及其复合材料显示出显着更高的拉伸模量和强度。这项研究为通过明智地使热塑性聚合物中的SWCNT对齐，为同时具有高TE和机械性能的聚合物复合材料柔性膜的铺装提供了有效的方法。