Hierarchically Flexible Polyamide Composite Films for Thermal Management and Electromagnetic Shielding

Abstract

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·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.

Interfacial Strain Analysis of Bending Bilayer Silicone Elastomer Films Using a Cholesteric Liquid Crystal Sensor

“…Understanding the interfacial strain in flexible polymer films with different mechanical properties is crucial for the development of next-generation flexible electronic devices consisting of polymer components − because strain degrades the conductive materials placed on the interface. − Investigation of interfacial bending strain in polymer films has relied on theoretical calculations and numerical simulations. − However, theoretical calculations based on the classical beam theory need to be modified to account for the large bending of polymer films because the theory only considers small bending strains below ∼3% (elastic region). Although numerical simulations using the finite element method (FEM) can analyze large interface bending strains (>3%), the results tend to vary with varied boundary conditions.…”

Development of biodegradable and low‐cost electromagnetic shielding composite by waste porous biochar and poly (butylene succinate)

“…Most of the non‐renewable fossil fuels chosen, till date, to prepare the composite material matrix, do not conform to the concept of green methods 34 . Engineering plastics, such as ultra‐high molecular mass polyethylene, 35 PP, 23 PS, 36 and PA6, 37,38 endow composite materials with excellent properties. However, the current recycling rate of waste plastics is low, and globally the average recycling rate of plastics is only about 18%.…”