Polyimide nanocomposite foams and aerogels for electromagnetic interference shielding

Lightweight and high-performance polymer-based electromagnetic interference (EMI)-shielding materials are crucial for the thriving miniaturized electronic telecommunication technology and wireless Internet of Things devices in aerospace, weaponry, artificial intelligence, personal wearable electronics, etc. Polyimide (PI) nanocomposite foams and aerogels are recognized as high-performance cellular materials, boasting exceptional thermal properties (thermostability, heat, and cold resistance), excellent mechanical properties, superior flame retardancy, and radiation resistance. Various types of lightweight PI nanocomposite foams and aerogels, offering exceptional EMI-shielding capabilities, have been developed for high-performance EMI-shielding applications. Researchers have dedicated significant efforts to create PI nanocomposite foams and aerogels using techniques such as chemical foaming, phase separation, supercritical foaming, the template method, and freeze drying, as well as carbon foams produced by carbonizing PI nanocomposite foams. The fabrication methods, cellular morphologies, EMI-shielding performances, and shielding mechanisms of the PI nanocomposite foams and aerogels are systematically summarized. Owing to their light weight, excellent EMI-shielding performances, and other desirable properties, PI nanocomposite foams and aerogels have garnered significant interest for high-performance EMI shielding in aerospace, weaponry, artificial intelligence, personal wearable electronics, etc.