Recyclable Nacre‐Like Aramid‐Mica Nanopapers with Enhanced Mechanical and Electrical Insulating Properties

The emerging aramid‐mica nanopapers, composed of aramid nanofibers (ANFs) and mica nanosheets (Mica), exhibit superiority in the field of electrical insulation compared with commercial aramid‐mica micropapers. Unfortunately, their mechanical and electrical insulating properties are still less than ideal due to insufficient control of their microstructures. Herein, it is presented that by integrating ANFs and Mica into nacre‐like aramid‐mica nanopapers with improved structural orderliness, densification, and interlayer interaction, simultaneously improved mechanical and electrical insulating properties are achieved. Their maximum tensile strength and breakdown strength reach ≈292 MPa and ≈176 kV mm−1, respectively, which are superior to those of the state‐of‐the‐art ANFs‐based nanopapers. Particularly, the aramid‐mica nanopapers show high resistance to high‐temperature (250–300 °C) and oil‐bath (100 °C) environments commonly involved in practical applications, and can be recycled many times, demonstrating their great potential as high‐performance sustainable electrical insulating papers to be applied in advanced electrical equipment. The aramid‐mica nanopapers with simultaneously and greatly enhanced mechanical and electrical insulating properties are fabricated by assembling aramid nanofibers and mica nanosheets into nacre‐like structures with improved structural orderliness, densification, and interlayer interaction. Particularly, this nanopaper shows high resistance to high‐temperature (250–300 °C) and oil‐bath (100 °C) environments commonly involved in practical applications, and can be recycled many times.