Degradable silver-plated epoxy foams with exceptional Joule heating and electromagnetic shielding properties

Designing degradable foams with excellent Joule heating and electromagnetic interference (EMI) shielding properties are crucial for protecting both the environment and low-temperature sensitive electronic devices. In this work, we used 1,3-diaminopropane carbamate (DPC) as a latent foaming-curing agent to prepare soft-hard tunable, degradable bio-based epoxy foams through one-step chemical foaming method. Subsequently, using F3 foam with outstanding reversible compressibility as the substrate, we developed a silver-plated foam, F3A3, with predominantly reflective and high EMI shielding performance via silver mirror reaction. The silver-plated foam F3A3 exhibited an electromagnetic interference shielding effectiveness (EMI SE) of 76.37 dB in the X-band (8.2–12.4 GHz), achieving a shielding efficiency as high as 99.99999%. Additionally, under an input voltage of 1.0 V, the surface saturation temperature of F3A3 rapidly increased from room temperature to 104.0 °C and demonstrated excellent stability and durability in low-voltage Joule heating. Due to the presence of dynamic ester bonds and tertiary amine structures in the F3A3 foam, it exhibited catalyst-free self-healing capability. These superior properties make the silver-plated foam highly promising for applications in military equipment, aerospace, and wearable electronic devices.