Hierarchically porous polyimide/TiCT film with stable electromagnetic interference shielding after resisting harsh conditions.

Polymer-based conductive nanocomposites are promising for electromagnetic interference (EMI) shielding to ensure stable operations of electronic devices and protect humans from electromagnetic radiation. Although MXenes have shown high EMI shielding performances, it remains a great challenge to construct highly efficient EMI shielding polymer/MXene composite films with minimal MXene content and high durability to harsh conditions. Here, hierarchically porous polyimide (PI)/TiCT films with consecutively conductive pathways have been constructed via a unidirectional PI aerogel–assisted immersion and hot-pressing strategy.

Super-elasticity at 4 K of covalently crosslinked polyimide aerogels with negative Poisson's ratio.

The deep cryogenic temperatures encountered in aerospace present significant challenges for the performance of elastic materials in spacecraft and related apparatus. Reported elastic carbon or ceramic aerogels overcome the low-temperature brittleness in conventional elastic polymers. However, complicated fabrication process and high costs greatly limited their applications.