Interface-Reinforced Segregated Conductive Networks in HDPE via In Situ Polyaniline Polymerization on Edge-Oxidized Graphene

The development of segregated structures in conductive polymer composites (s-CPCs) represents a promising approach for attaining superior electrical properties at reduced filler concentrations, yet enhancing the mechanical properties of s-CPCs while maintaining their high conductivity remains a crucial challenge due to inadequate interfacial bonding and inherent microstructural imperfections. By in situ polymerization of polyaniline (PANI) fibers on the surface of highly conductive edge-oxidized graphene (EOG) nanosheets, an interface-reinforced segregated structure was constructed in polyethylene (HDPE)-based s-CPCs with good mechanical properties and high electrical conductivity through a simple mechanical mixing and compression molding method. The PANI interlayer effectively suppressed EOG aggregation and bridged insulating gaps within the segregated conductive network, significantly reducing the surface resistivity to 6.56 × 103 Ω. Simultaneously, the surface-grafted PANI fibers facilitated HDPE molecular chain diffusion across interfaces, compensating for interfacial microdefects and enabling extraordinary ductility improvement, as evidenced by the elongation at break increased from 58% to 313%. This work provided a strategy for fabricating polyolefin-based s-CPCs with good mechanical properties and high electrical conductivity for applications.