Multifunctional, marvelous polyimide aerogels as highly efficient and recyclable sorbents

With the increasing awareness of environmental protection, it is imperative to develop advanced materials that can clean up spilled oil and organic contaminants efficiently. Herein, we designed and fabricated a series of novel polyimide (PI) aerogels by freeze-drying. The PI aerogels exhibit excellent absorption capability. The toluene absorption capability even ranked first among reported organic absorbents. The PI aerogels also exhibit good absorption recyclability. Surprisingly, the PI aerogels show high flexibility in liquid nitrogen, and liquid nitrogen absorbed by PI aerogels can be squeezed out repeatedly as if it were water in a sponge. What is more, PI aerogels are also usable as sorbents at high temperature and in harsh acid. These desirable attributes would enable PI aerogels to act as ideal sorbents in extreme environments. Together with thermal insulation and fire-resistance, the multifunctional, marvelous PI aerogels are expected to further extend their practical applications.