Interconnected network of Ag and Cu in bioplastics for ultrahigh electromagnetic interference shielding efficiency with high thermal conductivity

Abstract

Herein, we synthesize the silver (Ag)-copper (Cu) double layer via electroless plating of Cu using a thin Ag layer as a catalyst on the biodegradable polylactic acid (PLA). Then, we perform hot compression molding for fabricating PLA/Ag/Cu nanocomposites. We found out that the uniform thin Ag layer not only acts well as a catalyst for Cu deposition, but disperses Cu successfully to form a 3D Cu conductive network. And, Ag also enhances the oxidation resistance of Cu. Thanks to the homogeneous interconnected Cu structure along Ag, the fabricated PLA/Ag/Cu nanocomposites exhibit an exceptional electromagnetic shielding efficiency (EMI SE) of 101.8 dB at 0.5 mm thickness and excellent in-plane (11.22 W/mK), through-plane (3.44 W/mK) thermal conductivity with only Ag (2.4 vol%) and Cu (6.3 vol%).