Hierarchically Flexible Polyamide Composite Films for Thermal Management and Electromagnetic Shielding

With the integration and high power of electronic devices, as well as the rapid development of 5G and new energy, the application of materials with good flexibility, mechanical properties, and multifunctional properties is increasing. In this study, we prepared polyamide composite films with high thermal conductivity (TC) (33.27 W/(m<middle dot>K)), excellent electromagnetic interference shielding effectiveness (EMI SE) (63.0 dB), and good mechanical properties (tensile strength 44.5 MPa, toughness 13.8 MJ/m3) by using hierarchical design and recombination strategy. The top layer of the composite film is a graphene/graphene oxide film (GNP/GO) as the TC and EMI shielding layer. The base layer of the composite film is a commercially available polyamide mesh to improve mechanical properties. The dense Ni layer was deposited on the polyamide fabric by the electroless nickel plating process, which improved the shielding performance against electromagnetic interference. The water-borne polyurethane (WPU) cladding is further coated on the nickel-plated polyamide fabric to protect the cladding and bond the top and base layers simultaneously. In addition, the practical application of the film in thermal management and electromagnetic shielding fields is also proved through the application experiments.