Biomineralization-Inspired Confined-Space Fabrication of Polyimide Aerogels.

The biomineralization process endows biominerals with unique hierarchically porous structures and physical-chemical properties by filling the restricted microreaction space with amorphous phases before the growth of inorganic crystals. In this paper, a confined-space fabrication method inspired by biomineralization for preparing hierarchically porous polyimide (PI) aerogels and PI-derived carbon aerogels is introduced. The confined structure is established through a self-assembly method of vacuum impregnation and ultrasound-assisted freeze-drying. The hierarchically porous structure is controlled by adjusting the structure characteristics of the confined space and secondary aerogels. Subsequently, a variety of performance demonstrations are conducted to demonstrate the mechanical properties and application prospects in the fields of thermal insulation and electromagnetic shielding of the prepared aerogel.