Abstract Conductive polymer composites (CPCs) with segregated structure exhibit outstanding electromagnetic interference (EMI) shielding performance at low filler loadings. However, the mechanical performance is compromised due to poor interfacial adhesion resulting from the selective distribution of conductive fillers. Herein, a simple and effective approach, i.e. solid-phase extrusion (SPE), was proposed to fabricate segregated carbon nanotube (CNT)/poly(vinylidene fluoride) composites with high mechanical performance. Morphology examination revealed that both the matrix and segregated conductive network were highly oriented along the extrusion direction under the forceful flow field of SPE. The resultant SPE composites showed an excellent electrical conductivity of 74.5 S/m and a high EMI shielding effectiveness of 36.8 dB with only 4 wt% CNTs. More notably, simultaneous enhancement of the strength and fracture toughness was achieved. Compared to the counterparts with conventional segregated structure, tensile strength and elongation at break of SPE composites were significantly increased by ∼100% and ∼900%, reaching 120–140 MPa and 60%, respectively. This work demonstrates a valuable approach to prepare high-performance CPCs for EMI shielding applications.

中文翻译：

---

具有高电磁干扰屏蔽性能的偏析碳纳米管/聚偏二氟乙烯复合材料的机械性能大幅提高

摘要 具有隔离结构的导电聚合物复合材料 (CPC) 在低填料负载下表现出出色的电磁干扰 (EMI) 屏蔽性能。然而，由于导电填料的选择性分布导致界面附着力差，机械性能受到影响。在此，提出了一种简单有效的方法，即固相挤出（SPE），以制造具有高机械性能的分离碳纳米管（CNT）/聚（偏二氟乙烯）复合材料。形态学检查表明，在 SPE 的强力流场下，基体和分离的导电网络都沿挤出方向高度取向。所得 SPE 复合材料显示出 74.5 S/m 的优异导电率和 36.8 dB 的高 EMI 屏蔽效率，仅使用 4 wt% CNT。更值得注意的是，实现了强度和断裂韧性的同时提高。与具有传统分离结构的对应物相比，SPE 复合材料的拉伸强度和断裂伸长率显着提高了约 100% 和约 900%，分别达到 120-140 MPa 和 60%。这项工作展示了一种为 EMI 屏蔽应用准备高性能 CPC 的宝贵方法。