Flexible dielectric materials with ultrahigh energy density (U_e) is of critical importance to reduce the size of dielectric capacitors, which has recently drawn ever-increasing attention. Herein, different from the incorporation of traditional 1D/2D inorganic nanofiller into single/multi-layer polymer matrix, a multifunctional poly (p-phenylene terephthalamide) (PPTA)-based derivative fluxible polymer (f-PPTA) nanocluster is selected and introduced to typical ferroelectric poly (vinylidene fluoride) (PVDF) matrix. As a novel polymer-based nanofiller, the f-PPTA nanocluster consists of self-bundled parallel sulfonated PPTA skeleton and grafted with octadecylamine polyoxyethylene ether amphiphilic (PEGO) amine ligand through ionic interaction. In the multi-arm amphiphilic PEGO, one alkyl chain with the length of 15 carbon atoms provides similar hydrophobic nature to that of PVDF, which contributes to improving the interfacial compatibility between polymer nanocluster and matrix. Furthermore, the relatively short hydrophilic chain with the length of 8 carbon atoms induces a specific necklace-like arrangement of the f-PPTA nanoclusters in PVDF matrix during film fabrication spontaneously. Consequently, an ultrahigh U_e ~ 22.5 J•cm⁻³ of the dielectric film is acquired at 600 MV•m⁻¹ electric field. This value is the highest reported so far among all the poly (vinylidene fluoride) (PVDF)-based dielectric nanocomposites to the best of our knowledge. In addition, the elongation at break of the film can be increased to 390%, which is over 9 times that of pure PVDF sample. This work provides a new route to PVDF-based polymer nanocomposites with ultrahigh U_e and highly stretchable performance.

具有超高能量密度（U _e）的柔性介电材料对于减小介电电容器的尺寸至关重要，近来引起了越来越多的关注。这里，不同于将传统的1D / 2D无机纳米填料掺入单/多层聚合物基质中，选择多功能聚对苯二甲酰对苯二甲酰胺（PPTA）基衍生物可熔性聚合物（f -PPTA）纳米簇并将其引入典型的铁电聚偏二氟乙烯（PVDF）基质。作为一种新型的基于聚合物的纳米填料，f-PPTA纳米簇由自束缚的平行磺化PPTA骨架组成，并通过离子相互作用与十八烷基胺聚氧乙烯醚两亲（PEGO）胺配体接枝。在多臂两亲性PEGO中，一个长度为15个碳原子的烷基链提供了与PVDF相似的疏水性，这有助于改善聚合物纳米团簇与基质之间的界面相容性。此外，具有8个碳原子长度的相对短的亲水链在膜制备过程中自发地诱导了PVDF基质中f -PPTA纳米簇的特定项链状排列。因此，超高û _ë〜22.5Ĵ•厘米^-3在600MV·m ^-1电场下获得电介质膜的厚度。据我们所知，该值是迄今为止所有基于聚偏二氟乙烯（PVDF）的介电纳米复合材料中最高的。此外，薄膜的断裂伸长率可以提高到390％，是纯PVDF样品的9倍以上。这项工作为使用具有超高U _e和高拉伸性能的PVDF基聚合物纳米复合材料提供了一条新途径。