Electrical Conductivity of Silver‐Plated Epoxy Monoliths With Interconnected Pore Structures

Conductive polymer composites combine lightweight and high processability that are difficult to achieve with metals and are increasingly important in various applications. Epoxy monoliths, which possess a continuous epoxy skeleton and interconnected microscale pores, offer unique opportunities for composite fabrication through their pore network and large internal surface area. In this study, we fabricated a conductive polymer composite in which silver was selectively deposited on the pore surfaces of an epoxy monolith via the Tollens' reaction, resulting in interconnected silver particles. By systematically examining the effects of plating conditions and monolith pore structures on silver growth, we clarified that the formation of a three‐dimensionally continuous silver network depends not only on silver content but also on the spatial distribution and interconnectivity of silver along the pore surfaces. As a result, electrical conductivities on the order of 10 3 –10 4 S/cm were achieved at a silver content of approximately 20 vol%, calculated based on the total apparent volume of the monolith, including the pore (void) volume, without the use of high‐aspect‐ratio conductive fillers. Tensile tests and cyclic tensile tests were performed to clarify how silver accumulation affects the mechanical response of the monolith framework and the durability of the conductive pathways.