Inspired by the hierarchically dendritic structure of plant root and its extraordinary ability of grabbing soil, polyurethane (PU) fibers with such bio-mimic structure were fabricated by non-solvent induced precipitation under turbulent force to grab multi-walled carbon nanotubes (CNTs) in this work, forming interpenetrating segregated network (IPSN) with CNTs coated on hierarchically dendritic polyurethane (PU) fibers (HDPUFs) and filled into voids between entangled HDPUFs. Prepared CNT/PU composites illustrate an ultrahigh maximum CNT loading of 80 wt% with good flexibility, while only 10% could be achieved for common segregated structure. Meanwhile, a low percolation threshold of 0.25 wt% and a maximum conductivity of 25 S/cm is achieved. Benefiting from significantly reduced insulating polymer coating on CNTs, the electrical conductivity of CNT/HDPUF composites at low CNT loading (≤7 wt%) is orders of magnitude higher than that of CNT/PU composites containing randomly dispersed CNTs with similar filler content. Simultaneously, the specific electromagnetic interference (EMI) shielding efficiency (SE) of CNT/HDPUF composite reaches up to 10526.1 dB cm²/g thanks to their high electrical conductivity and low density, which has been rarely reported previously for CNT-based composites. This work provides a simple and low-cost method to fabricate thin, lightweight, and flexible composite with high filler content, high electrical conductivity and outstanding electromagnetic shielding performance.

受植物根系的分级树枝状结构及其非凡的抓土能力的启发，具有这种仿生结构的聚氨酯 (PU) 纤维在湍流力下通过非溶剂诱导沉淀制备，以抓取多壁碳纳米管 (CNTs)在这项工作中，与涂覆在分层树枝状聚氨酯 (PU) 纤维 (HDPUF) 上的 CNT 形成互穿隔离网络 (IPSN)，并填充到缠结的 HDPUF 之间的空隙中。制备的 CNT/PU 复合材料显示出 80% 的超高最大 CNT 负载量和良好的柔韧性，而普通分离结构只能达到 10%。同时，实现了 0.25 wt% 的低渗透阈值和 25 S/cm 的最大电导率。得益于显着减少的 CNT 绝缘聚合物涂层，CNT/HDPUF 复合材料在低 CNT 负载量（≤7 wt%）下的电导率比含有类似填料含量的随机分散的 CNT 的 CNT/PU 复合材料的电导率高几个数量级。同时，CNT/HDPUF复合材料的比电磁干扰（EMI）屏蔽效率（SE）高达10526.1 dB cm² /g，这要归功于它们的高导电性和低密度，这在以前很少报道过基于 CNT 的复合材料。这项工作提供了一种简单且低成本的方法来制造具有高填料含量、高导电性和出色电磁屏蔽性能的薄、轻、柔韧的复合材料。